Predicting temperature profile and temperature history for varied parameters of a welding process using Rosenthal’s approach for semi-infinite solid

Djarot B. Darmadi.

Temperature profile and history can be used to characterize a welding process. This paper applied Rosenthal’s thermal solution of a moving heat source over infinite solid to grab ideas how parameters involved in the welding process affect temperature profile and temperature history of selected nodes. Based on parametric study, it can be concluded that higher thermal conductivity caused shallow penetration since the embedded heat tend to spread out to the cooler region. To obtain equal penetration the power should be increased, but this caused the faster cooling rate. Increasing the welding speed has equal influence with elevating the specific heat that causes narrower isothermal lines although their length insignificantly altered.

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Extraction of essential oils from patchouli plant using advanced techniques of microwave-assisted hydrodistillation

Nurkholis Hamidi

Microwave-Assisted Hydrodistillation (MAHD) is an advanced technique for extraction process, in which microwave heating process is used. MAHD and hydrodistillation (HD) methods have been studied and the results were compared for their effectiveness in the extraction of essential oils from patchouli leaves. In present study the MAHD methods was operated with some levels of electrical power. The results showed that MAHD methods can reduce the extraction time and increase the yield. MAHD was also found to be a green technology since it required less energy than HD. The energy consumption of HD is 30% higher than MAHD. The results also indicated that power levels of MAHD have significant effect on ultimate extraction yield and time consumption. The higher power of MAHD can obtained higher ultimate yield.

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The utilization of paraffin and beeswax as heat energy storage in infant incubator

Sekar Sinaringati, Nandy Putra, Muhammad Amin and Fitri Afriyanti

Electrical energy is generally used for heat source on infant incubator. The infant incubator operation is dependent on electrical energy. Infant incubator is primary required by hospital patients particularly for the mother who just giving birth the premature infant. When electrical energy is shutdown, the infant incubator cannot operate to fulfill that need. The solution is by creating new technology to look for material, which is capable to keep the heat energy to warm the infant body if there is no electrical source. Paraffin and beeswax are phase change materials (PCMs) that are able to give heat energy to warm up infant incubator. Paraffin and beeswax have high latent heat to keep and release the heat at constant temperature. This study was focused on the utilization of the comparison of paraffin and beeswax materials as the sources of heat energy on infant incubator. The results showed that the PCMs can maintain heat energy at the temperature above 32°C for more than 8 hours in the infant incubator room. However, it was observed that beeswax performed better in heat energy storage than paraffin. This study suggests the utilization of beeswax as the PCM for infant incubator, and possibly for any other practical application.

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Numerical investigation on ejector as an expansion device using R290 in residential air conditioner for various cooling capacity

ARIES Prih Haryono, KASNI Sumeru, AZHAR Abdul Aziz and HENRY Nasution

Typically, the residential air conditioner uses capillary tube as an expansion device. The friction between refrigerant flow and pipe wall, and also the changing of the velocity along capillary tube cause energy loss during expansion. The pressure drop from the condenser to the evaporator caused by capillary tube is considered isenthalpic process. An ejector as an expansion device can be used to recover energy loss during expansion process. Many researchers reported that the use of an ejector as an expansion device in vapor compression refrigeration cycle (VCRC) may lead to increase in the system performance. In this study, the numerical investigations were carried out on the residential air conditioners using the VCRC for various cooling capacity with R290 as working fluid. At present, the working fluid of R22 is widely used as refrigerant in residential air conditioners. Because R22 has a high global warming potential (GWP), as a result it must be phased out in the near future. Researchers recommended R290 (propane) as a substitute refrigerant for R22. As a natural refrigerant, R290 is abundant and relatively cheaper than that of R22. In addition, many studies reported that retrofit from R22 to R290 in air conditioner may result increase in coefficient of performance (COP). As a result, this study investigates the use of R290 for replacing R22 in residential air conditioner for various cooling capacity, viz. 2.5, 3.8 and 5.0 kW or the compressor capacity of 1, 1.5 and 2 HP. Three equations, i.e., conservation equations of mass, momentum and energy were applied to determine physical properties on each section of the ejector and the performances of the air conditioners. The main geometrics parameter of an ejector is area ratio (AR), which is defined as the ratio between the cross-sectional areas of mixing chamber and motive nozzle. The results showed that the diameter of motive nozzle is constant with the increase in ambient temperature, whereas the mixing chamber diameter slightly increases with the increase in ambient temperature. Meanwhile, the area ratio of ejector decreases with the increase in compressor capacity. In addition, the COP improvements of air conditioners are 4.94, 12.24 and 20.28% for ambient temperature of 30, 35 and 40oC, respectively.

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Experimental study of thermal efficiency on plate-fin solar thermal collector

Tri Ayodha Ajiwiguna, Tesla Hamonangan and Muhammad Ramdlan Kirom

Plate-fin solar thermal collector with the dimension of plate 40 x 80 cm and 13 fins is constructed and its performance is investigated. Ambient air is forced to flow through the solar collector by using fans. The measurements of incident solar radiation, input air temperature, output air temperature, and velocity of air flow are conducted simultaneously. Data from measurements are used to calculate heat absorbed by air flow and the efficiency of solar collector system. The results show that the increasing of air temperature is 14.3 oC, averaged heat power absorbed is 102.1 W, and the thermal efficiency is 49%.

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Numerical simulation of cross-flow around four circular cylinders in-line square configuration near a plane wall

A. Grummy Wailanduw, Triyogi Yuwono and Wawan Aries Widodo

Flow cross around circular cylinders arrangement could be found in many engineering application, such as reaction tower, cooling tower, shell and tube heat exchangers, and tube banks. When flow crosses the bodies, it would form particular flow pattern according to the body’s arrangements. Author [19], investigated a four circular cylinders arrangement near wall with spacing ratio (L/D) = 1.5 and gap ratio (G/D) of 0.2. They found that interaction between cylinders and wall caused a difference stagnation point in upstream cylinders and shear layer of upstream cylinders reattach in downstream cylinders. In this research, it would be investigated numerically flow characteristics on four circular cylinders in in-line square configuration near a plane wall. A gap ratio between the surface of lower cylinders and the wall (G/D) would be varied. It is set at G/D= 0.1, 0.3, and 1.0, while spacing ratio between centre of cylinders (L/D) was fixed at 4.0. To analyze flow characteristics around cylinders is used FLUENT 6.3.26 software. Two-dimensional Unsteady Reynolds Averaged Navier Stokes equations and SST k-? turbulence equations are solved with finite volume method. This simulation was performed at Reynolds number 53000 based on a single circular cylinder diameter. The numerical results show that an increasing of gap ratio cause of stagnation point of the upstream cylinder of lower row move to front of cylinder, while the upstream cylinder of upper row tends to not change. At the gap ratio G/D= 0.1 and G/D= 0.3, shear layer of the upstream cylinder of lower row cover the downstream cylinder of lower row, while a different phenomenon occur in the downstream cylinder of upper row. Shear layer of the upstream cylinder of upper row reattach on surface of the downstream cylinder of upper row.

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A comparison process of 3D model quality using 3D laser scanning triangulation method

Sally Cahyati, Mark Budiman and Fadhli Umar Lubis

The quality of the 3D model scanning results are determined based on the percentage of similarity in both geometry and dimensions of the model to the real product, as well as models surface smoothness. The 3D models of scanning results are strongly influenced by the methods and devices which are used in the scanning process. Triangulation method is used in this study to determine whether the camera of a mobile phone can replace the web camera which is used as input devices in a 3D laser scanner. Next, it will be seen whether the quality of the scanning can meet the specified accuracy requirements, Three types of mobile phone cameras with the same specifications will be tested and seen their validity. Every smart phones have a surface refinement optimal level and a good DSP (Dimension Deviation Percentage) of 3D Models in the scanning distance (z) is ± 250 (mm). In This position the ratio percentage of 3D model has the closest geometry to the original product.

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Bottom shear stress and bed load sediment transport due to irregular wave motion

Suntoyo, A Harris Fattah, Muhammad Yunan Fahmi, Taufiqur Rachman and Hitoshi Tanaka

Waves in ocean are generally irregular and have a random shape with variation in orbital velocity, wave height and period. The accuracy of sediment transport model is the most important stage to model the coastal morphological change. In addition, the coastal morphological change model is more efficient to use the bottom shear stress calculation approach for practical purposes rather than a more complex approach to the modeling of two phases. In this paper, the calculation method of sediment transport based on the bottom shear stress purposed with data validation from the experimental results in the turbulent bottom boundary layer over rough bed under irregular waves. The new approach to estimate the bottom shear stress was based on combining velocity and acceleration terms as formulated was modified to be proposed to calculate the bottom shear stress under irregular wave motion. Furthermore, a new approach of the bottom shear stress was applied to model the bed load sediment transport rate for irregular waves by using the experimental data as validated model. Measurement of water surface elevation and bed load sediment transport rate under irregular wave motion was carried out in wave flume tank generated by Jonswap spectrum in variation of wave height and period. Moreover, the new method gave the smallest the RMSE value indicating that the new method has the best agreement with the bottom shear stress and bed load sediment transport of experimental results.

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Design concept of small long-life PWR using square and hexagonal thorium fuel

M. NURUL Subkhi, ZAKI Su’ud, ABDUL Waris and SIDIK Permana

Long life reactor is a nuclear power plant which can be operated 10-30 years of operation without the need for refueling. Such Nuclear Power Plant is very good to supply electricity in remote area in Indonesia and in general outside Java Bali Area. Here, a Design study of small long-life Pressurized Water Reactor using thorium cycle has been performed with fuel fraction 60%. The neutronic calculations were performed by PIJ SRAC code using nuclear data library based on JENDL 4.0, while the core burn up calculations were optimized in whole X-Y-Z geometry by COREBN. The strategy is by the reduction of moderator by adopting tight lattice model based on hexagonal geometry cell and by the use of Pa-231 as burnable poisson material which give good long life core during burnup time. The optimization of 350 Mwt small long life PWR based on thorium nitride fuel system has excess reactivity as low as about 1% dk/k and flatted power distribution during its operation.

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An improved load-displacement prediction for a coned disc spring using the energy method

Noor Fawazi and Jung-Youn Lee

An improved computation of the load-displacement prediction for a coned disc spring is proposed. This work is an extension work of the previous proposed energy-based computation for coned disc springs. To show the validity of the improved method, the load-displacement results using the improved computation, the previous proposed method, and the finite element analyses are compared. In this work, the improved computation and the finite element analyses have accounted for the radial deflection of the disc spring in the form of energy method. This is different in the previous work where the radial deflection of the disc spring was ignored and the comparison to the finite element analyses without accounting the radial deflection is not practical. The present work makes the comparison to the finite element analyses to be more reasonable and more practical.

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An improved energy based load-displacement prediction for slotted disc spring

Noor Fawazi and Jung-Youn Lee

An improved calculation of the load-displacement prediction for a slotted disc spring is proposed. There are two types of slotted disc spring; a straight slotted disc spring and a bended slotted disc spring. By considering these two types of slotted disc spring, this work attempts to extend the previous work on load-displacement prediction for the slotted disc spring using the energy method. To show the validity of the improved method, the load-displacement results using the improved computation, the previous proposed method, and the finite element analyses are compared. In this work, the improved computation and the finite element analyses have accounted for the radial deflection of the disc spring which is different in the previous work. The radial deflection of the disc spring was ignored in the previous work and the comparison to the finite element analyses without accounting the radial deflection is not practical. The present work is compared to the finite element analyses which make the comparison to be more reasonable and more practical.

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Numerical study of flow characteristics around an I-type cylinder 53° near a plane wall

Tri Yogi Yuwono, Ahmad Tohir and Purwanto

The flow characteristics around an I-type cylinder with cutting angle 53° located near a plane wall was investigated numerically in a uniform flow at a Reynolds Number of 5.3 x 104, based on a circular cylinder diameter (D). The pressure distributions along the surface of the cylinder and the plane wall were simulate by varying the gap-to-diameter of cylinder ratio (G/D) in the range of 0.1 < G/D < 0.3, using FLUENT 6.2 software. The 2D U-RANS numerical simulation with k-? SST as viscous model was used to visualize the flow phenomena occurred around the cylinders. The results show the existence of the bubble separation in the lower side of cylinder for the gap ratio G/D of 0.1 to 0.3. It was practically confirmed by the experimental results by measuring the pressure distribution around the cylinder and along the surface of plan wall.

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Effect of carbon coating on electrochemical performances of LiTi₂(PO4)₃ as anode for aqueous electrolyte lithium ion battery

Lukman Noerochim, Zeddy Argasani and Diah Susanti

One of the renewable energy storage systems that are widely used today is the rechargeable lithium-ion battery. There are four main components in the rechargeable lithium-ion battery, one of which is anode. In this research, LiTi₂(PO4)₃ with nasicon-type crystal structure is introduced as a candidate for anode material for aqueous electrolyte lithium ion battery. Conductive coating process is applied to improve the conductivity of LiTi₂(PO4)₃ by heating sucrose at 600°C for 3 hrs in an argon gas to form carbon-coated LiTi₂(PO4)₃ (LiTi₂(PO4)₃/C). The content of carbon in LiTi₂(PO4)₃/C is measured as much as 8%, 13%, and 17.2% wt. CV results show that the addition of carbon can improve the stability, electronic conductivity, and specific capacity LiTi₂(PO4)₃. In the charge-discharge results, LiTi₂(PO4)₃ with 8% of carbon enhance the intercalation lithium ion with the highest charge capacity of 45.9 mAh/g after 100 cyclic. Based on all the results, LiTi2(PO4)3 could be the potential candidate as anode for aqueous electrolyte lithium ion batteries.

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The variety of furniture arrangement inside apartment unit around Jabodetabek area to improve COPc

Bambang Iskandriawan

An exploration of wall split air conditioning (AC) unit working in some apartments around Jabodetabek is conveyed based on the variety of furniture layout. The type of furniture arrangement of the apartments is exclusively developed to investigate their influence to the cooling coefficient of performance (COPc). The study was focused on the establishment of the flow pattern uniqueness depend of the furniture arrangement. Using computational fluid dynamics tool, several variables were exploited such as apartment location and furniture layout. It is obtained specific air flow pattern since every single room within operated wall split AC unit which is control the COPc degrees. There are five furniture layout designs for every city therefore it is obtained twenty-five different airflow patterns which is influence the performance of AC unit. It is concluded the best furniture arrangement for all city where it could be operated within the lowest energy consumption of air conditioning. The effort to reduce the electricity energy consumption of air conditioning operation in the building industry is in line to the Indonesia government policy. The selection of furniture arrangement which is the best COPc is the one method to realise the energy saving program. Besides the number of Indonesia apartment building is very excessive particularly in the big metropolises such as in Jabodetabek (Jakarta, Bogor, Depok, Tangerang and Bekasi) area.

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Feasibility analysis of Grid/Wind/PV hybrid systems for industrial application

The present study offers technical and economical analyses of grid-connected hybrid power systems for a large scale production industry located in Bali. The peak load of observed system can reach 970.630 kW consuming on average 16 MWh of electricity a day. Software HOMER was utilized as the optimization tool. The proposed hybrid renewable energy systems consist of wind turbines, a PV system, a converter, and batteries. The system is connected to the grid. Optimization results show that the best configuration is the Grid/Wind hybrid system with the predicted net present cost of -884,896 USD. The negative sign indicates that revenues (mostly from selling power to the grid) exceed costs. The levelized cost of electricity of the system is predicted to be -0.013 USD/kWh. The present study also conducts sensitivity analysis of some scenarios i.e. 50% and 100% increases in grid electricity prices, 50% reduction of PV and WECS prices, and 10 USD and 50 USD carbon taxes per ton CO₂ emission. Implications of the findings are discussed.

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Effect of temperature and time of two-step austempering method on mechanical properties for nodular cast iron

This research attempts to investigate the mechanical properties of nodular cast iron using new heat treatment technique. Novel two-step austempering technique was executed to obtain better mechanical properties for nodular cast iron. The results from this method were then compared to a conventional heat treatment, namely single-step austempering method. Single-step and two-step austempering methods were done at 900 °C of austenitic temperature for 60 minutes. For two-step austempering method, the second step started at 260 °C for 10 minutes increased gradually at 280, 310, and 340 °C for 60 minutes. The mechanical properties of nodular cast iron increased significantly using two-step austempering method compared to the conventional and single-step austempering methods. The highest tensile strength was obtained using two-step austempering method at 340 °C for 60 minutes followed by 310 °C and 280 °C. On the contrary, the toughness of nodular cast iron decreased at 340 °C.

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Improving the injection molding of small optical elements by integrating reverse engineering and mold flow analysis

Small optical lenses are usually manufactured by injection molding. The high quality requirement on injection lenses, however, requires a precise control of the mold accuracy as well as the injection process. The purpose of this study is to conduct a comprehensive error study of the injection molding for optical elements by combining the techniques of reverse engineering and mold flow analysis. Reverse engineering is employed to identify the source of errors, and hence provide guidelines for the modification of the mold; Mold flow analysis is employed to construct a parametric study of the injection process, and hence improve the quality of injection parts. Real molds are designed and manufactured, and injection molding is implemented to verify the feasibility of the simulation. The advantages of the proposed method by integrating reverse engineering and mold flow analysis for improving the injection process are discussed too.

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Analysis of the influence of hydraulic cylinder diameter to the total damping force and the generated electricity of regenerative shock absorber

This paper deals with analysis on the influence of hydraulic cylinder diameter and oil viscosity to the total damping force and the regenerated electric power of hydro-magneto-electric-regenerative shock absorber (HMERSA). HMERSA is aimed to convert the vibration energy losses from the vehicle suspension into electricity. As HMERSA consists of mechanical and electrical system, the total damping force characteristics and the regenerated electric power will be influenced by its mechanical and electrical damper characteristics. In HMERSA, the mechanical damper depends on the design of the hydraulic cylinder diameter, oil viscosity and the existing head loss, while the electrical damper is affected by the electric generator characteristics and battery state of charge. In this study, a previously developed prototype of HMERSA was mathematically modelled, simulated and analyzed. The influence of hydraulic cylinder-tube diameter ratio (3.2, 4, 5) to the total damping force and the regenerated electric power of HMERSA were simulated. The results are presented, analyzed and discussed in this paper.

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Analysis of wave climate variations based on ERA-Interim reanalysis data from 1980 to 2014 to support wave energy assessment in Indonesia

In this study, temporal variation in significant wave height are studied using ERA-Interim reanalysis data from ECMWF (European Centre for Medium-Range Weather Forecasts) for 35 years period from 1980-2014 to support energy assessment in Indonesia Sea. The ERA-Interim reanalysis data provides wind speed and wave height data with resolution of 0,750 x 0,750. This paper studied monthly variation in significant wave height and wind speed by creating monthly data and taking the mean of those months over a period 35 years. A statistical analysis of wave and wind time series data has been performed to test the significance of trend during 35 years period. Mann-Kendall test is used to evaluate the trend of time series data in terms of mean value. The results show that temporal variations in wave height have an associated pattern with monsoonal wind cycle. In addition, the mean significant wave height in the South of Java Sea show statistically significant increasing trend for all months. The result indicated that the wave energy have the potentiality to contribute in the Indonesian energy demand.

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Investigations of the mixed mode crack growth behavior of an aluminum alloy

Fracture behavior of aluminum alloys under mixed mode (Mode I+II) loading was studied. Fracture tests were carried out on A2024-T351 aluminum. Compact-tension-shear specimen was employed and angle between loading axis and the crack surface was varied from 90°(mode I) to 0°(mode II). The crack extension (crack initiation and propagation) behaviors observed by a video microscope. Under a load with relatively high mode II components, the shear type crack initiation preceded the opening type crack propagation. Final fracture was occurred by shearing instability in the pure mode II loading. The critical values of stress intensity factors at crack initiation under mode II dominant conditions become smaller than those predicted by the maximum hoop stress criterion. Shear type fracture instability occurs at the ligament when the shear stress is over the shear strength of the material. It was also found that the rolling direction and a small holes existing ahead of the crack-tip influence the crack extension behavior.

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Effects of citric acid/BaTiO3 weight fractions and time of sintering in sol gel process on electric saturation polarization values and phase composition

The excellent dielectric and ferroelectric properties of barium titante (BaTiO3/BTO) make it attractive material in the field of electron-ceramic and microelectronics. The aim of this research is to find optimum process condition of sol-gel method for BTO synthesis by varying of citric acid/BTO weight fractions and time of sintering. It is expected to obtain BTO material in nanoparticle, single phase and good electric properties by this method. It was used barium nitrate, titanium oxide, nitrate acid, ammonium nitrate as precursors and citric acid (C6H8O7) as a fuel. The parameters which are varied are weight fraction of citric acid/BTO = 1:1, 2:1 and 3:1 and time of sintering 2 and 4 hours at 700oC respectively. To know the temperature of phase transition it was used TGA/DTA (Thermo Gravimetric Analysis/Differential Thermal Analysis) test for BTO gel. Phases formation of material were carried out using X-Ray-Diffraction (XRD) for BTO powder. It was used Particle Size Analyzer (PSA) with Beckman Coulter DelsaTM Nano type to know particle size of BTO powder. “Home made electric instrument by Physics Department of University of Indonesia” was used to know electric properties of BTO powder. XRD results confirm that single phase BTO is obtained on weight fraction of citric acid/BTO =2:1 with time of sintering 2 hours at 700oC. The process condition produces nanoparticle BTO with particle size of 45 nm. Measurement with electric hysteresis loop shows that BTO powder with the process condition has the highest value of electric saturation polarization, 44.84 µC/cm2 and good loop of electric hysteresis.

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Design and modeling fender system for condensate and Sulphuric Acid Jetty at Senoro field, Central Sulawesi

This paper describes detailed investigations of the analysis and design of a proposed fender system for condensate and sulphuric acid jetty at Senoro, Central Sulawesi. Fender is basically the interface between a vessel and the berth facility. This medium serves to absorb a certain portion of the kinetic energy of a vessel without damage to the vessel and the waterfront structure. Finite elements analysis was performed on a cell fender system subjected to impact load caused by a vessel collision. The impact load was converted into equivalent static load. The selection of the most efficient fender system is based on the principle on energy absorption of the system to the impact load and stress analysis deflection. Fender system consist of steel structure property for fender panel and styrene butadiene rubber property for fender rubber was designed for Condensate and Sulphuric Acid Jetty with maximum tensile strength of 16 MPa.

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Synthesis of BiFeO₃ nanoparticle and single phase by sol-gel process for multiferroic material

The magnetoelectric coupling (ME) in multiferroics i.e. BiFeO₃ promises important technological applications in several multifunctional devices like data storage, spinotronics, sensor, actuator devices etc. BiFeO₃ was synthesized using a sol - gel process. The aim of this research is to find optimum process condition of sol-gel method for BiFeO₃ synthesis by varying of sintering temperature. It is expected to obtain BiFeO₃ material in nanoparticle, single phase and shows electric voltage response if given an external magnetic field. It was used Bi₅O(OH)₉.(NO₃)₄, Fe(NO₃)₃.9H₂O, HNO₃, H₂O as precursor and citric acid (C₆H₈O₇) as fuel. It was used 450oC; 500oC and 550oC as sintering temperature for 10 hours respectively. Phases formation of material were carried out using X-Ray-Diffraction (XRD) for BiFeO₃ powder. It was used Particle Size Analyzer (PSA) with Beckman Coulter DelsaTM Nano type to know particle size. “Home made ME instrument by Physics Department of University of Indonesia” was used to know electric voltage response when given an external magnetic field to BiFeO₃ powder. XRD results confirm that single phase BiFeO₃ is obtained at sintering temperature of 550oC for 10 hours. The smallest particle size was 65 nm. When BiFeO3 powder was given an external magnetic field, it shows electric response. This response shows that the powder has multiferroic characteristic.

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Analysis of effect of sub cooling performance of vapor compression refrigeration system with cooling load variation

One method to improve the performance of vapor compression refrigeration system using sub cooling and environmentally friendly refrigerant. Hydrocarbon refrigerant is one of the environmentally friendly refrigerants that are proven to improve the performance of vapor compression system without sub-cooling. To that end, this for study aimed to analyze the effect is liquid-suction sub cooler and cooling load on the performance of the vapor compression refrigeration. Refrigerant R134a and R600a are used, the cooling load variations using lamps. Sub-cooling heat exchanger mounted between condenser and expansion. Variations in the mass amount of refrigerant through the sub-cooling is used the valve. The greater the sub-cooling temperature, the greater the temperature drop in the evaporator, and the cooling effect increases, and the cooling effect with refrigerant R600a is greater than R134a. The increase in compressor work is not affected by the magnitude of the cooling load, but is influenced by the amount of capacity sub-cooling. The greater the sub-cooling and cooling load, the greater the increase in compressor work. Use of sub-cooling effect COP increase and the increase COP R600a is greater than the COP R134a. Broadly speaking that R600a can be used as a substitute refrigerant R134a.

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The effect of Co₂ fraction on the flame stability of biogas premixed flame

This study aimed to determine the effect of CO₂ on flame structure and stability of premixed flames biogas using counterflow flame configuration. In this research, the CO₂ fraction in Biogas was varied from 0% to 50%. The total mass flow of gas flowed from both combustion nozzle was varied within 6 L / min and 8 L / min. The burning behavior of biogas counterflow flames were photographed by digital camera. Besides, the stability limit of counterflow diffusion flame was characterized by the minimum oxygen concentration at extinction. The results showed that the CO₂ content in the biogas affect the characteristics of premixed flame, especially the change of a blue flame to blue flame with lower luminosity when increasing CO2 concentration. On the other hand, the variation in the oxygen concentration has more significant effect on the dimension of the premixed flame compared to the effects of the CO₂ content in the biogas. The flash back phenomena exist in the counterflow premixed flame when the equivalence ratio of reactant close to 1. It means that the biogas combustion is recommended to be done in the equivalence ratio close to 1 in order to obtain the best combustion performance. The results also showed that the highest concentration of oxygen minimum to keep the biogas premixed flame remained stable occurred in the percentage of CO₂ in the biogas is 30%. This result could be explained based on the composition of unburned CH₄ and CO₂ gas in the combustion process.

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The calorific values of solid and liquid yields consequenced by temperatures of mahogany pyrolysis

Due to the potential pyrolysis products to be bio- fuels, the pyrolysis yield products were measured its calorific indicating important-physical properties of fuel. The study aims to analyze the influence of different temperatures on the calorific value of pyrolysis by means of calorimetrical measurement. The biomass feedstock used was mahogany wood, and then it would be pyrolyzed in the slow pyrolysis experimental run. The pyrolysis temperatures were conducted from 250?C to 800?C and the heating rate at each process was 0.44°C/sec. It was accompanied to proceed for 3 hours. The influence of temperature toward the solid (char) and liquid (tar) yields were examined by means of a bomb calorimeter. The result was presented by the potential products of mahogany wood pyrolysis in the mass and volume changes of char dan tar. Then, the char and tar were measured its calorific values. The calorific value of untreated mahogany wood (before pyrolyzed) were around 3700 kal/g, but the pyrolysis treatment significantly increased its calorific values in various pyrolysis temperatures. It referred that the calorific values of solid yields were pointed in the increasing values with the increasing of pyrolysis temperature, however, the calorific values of tar inclined up to temperature of 500?C, however, it would decline because the density of tar become lower. The variance in calorific values could be attributed to the chemical composition of the mahogany wood; indeed, it was known a larger amount of carbon percentage. Furthermore, the percentage of carbon tends to increase in the pyrolysis wood.

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The dynamic characteristics of vertical axis wind turbine type H

This paper studied about the dynamic characteristics of vertical axis wind-turbine type H. From the rotor dynamic viewpoint, vertical axis wind-turbine (VAWT) has weakness point compared to the horizontal axis type wind-turbine. The tower has sustained the multiple loads except the weight loading of the Wind-Turbine’s blades itself. All the rotational loads were transferred directly to the tower. It follows that several problems that often occurred are natural frequencies vibration with its mode shape. The experimental investigation of the vibration, by using the static bump test and dynamic test, were performed to acquire the natural frequencies of the wind-turbine system. Furthermore, by using numerical simulation code ANSYS, the wind-turbine system was simulated to obtain dynamic response of the wind-turbine system and to identify the critical parts of the wind-turbine system. The simulations results show that the critical part of VAWT type H was shown on the tower which may cause significant dynamic deformation. The natural frequencies and the structural strength of the H type wind turbine are higher.

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Experimental study of the influence of quenching and partitioning temperature variation on retained austenite fraction in AISI 4140 steel

Quenching partitioning, the recent heat treatment method, offers a way to enrich carbon in retained austenite at room temperature. This method consists of 4 steps; austenizing, premier quenching, partitioning, and secondary quenching. Afterward, specimen was etched and observed under microscope and x-ray diffraction to obtain microstructure. Retained austenite fraction affected by premier quenching temperature and partitioning temperature was examined. Using this experimental data, the possible forming mechanism was explained and results of mechanical testing was used to verify the influence of retained austenite on mechanical properties.

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Performance improvement using subcooling on freezer with R22 and R290 as refrigerant for various ambient temperatures

CECEP Sunardi, LUGA Martin, KASNI Sumeru and HENRY Nasution

Vapor compression refrigeration cycle (VCRC) is widely used in freezers. In a simple cycle of the VCRC, refrigerant in the condenser exit is at liquid saturated line. If the refrigerant temperature in the condenser exit is further cooled to the subcooled region results in an increase in the cooling capacity due to low vapor quality of refrigerant entering the evaporator. The lower the refrigerant quality entering the evaporator, the higher the cooling capacity on the evaporator. The increase in the cooling capacity enhances the freezer performance. Subcooling uses liquid suction heat exchanger (LSHX) is applied to transfer heat from the exit of the condenser (liquid line) to the suction of the compressor. Because the temperature of liquid line is higher than that of the suction line, heat flows from liquid line to the suction line, results in the decrease in temperature of the exit of the condenser and the increase in the suction temperature (superheating). Consequently, the use of the LSHX is always followed by superheating on the suction of the compressor. The superheating causes an increase in the input power. As a result, subcooling using the LSHX is not always followed by the increase in the coefficient of performance (COP) of the freezer, depending on the type of refrigerant used. Refrigerant of R22 is widely used as refrigerant in the freezers. Because R22 has a high global warming potential (GWP), the near future this refrigerant must be phased out. Refrigerant of R290 (propane) is recommended as a substitute refrigerant for R22. The R290 is a natural refrigerant, abundant and relatively cheaper than that of R22. This paper investigates the use of LSHX subcooling in freezer with the evaporating temperature of -20oC for various ambient temperatures, viz., 30, 35 and 40oC using R22 and R290 as working fluids. It is well known that the COP of the freezer decreases with an increase in the ambient temperature. As a result, the use of the LSHX subcooler is expected to enhance the COP of the freezer for the higher ambient temperatures. There are three parameters, viz., the cooling capacity, the discharge temperature and COP improvement will be investigated in the present study. Numerical results showed that the increase in subcooling and ambient temperature increase the cooling capacity and COP improvements. In addition, the cooling capacity and COP improvements of R290 using the subcooling of LSHX were higher than that of R22 for all ambient temperatures. Also, the increase in degree of subcooling enhanced the cooling capacity and COP improvements. For R22, at the ambient temperature above 35°C is not recommended using LSHX subcooling in freezers, because it will increase the discharge temperature above 90oC. However, the use of LSHX subcooling is recommended for all ambient temperatures in freezer using R290, because the discharge temperature on the freezer is still below 80°C.

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Biomechanical analysis of spider silk for anterior cruciate ligament reconstruction

Luis Carlos Ruiz Cárdenas, Olga Ramos Sandoval and Dario Amaya Hurtado

Advances in bioengineering research related to orthopedic surgery, have focused on the development of biocompatible materials in order to provide alternative solutions for rebuilding organic tissues of the human body. In this work, the biomechanical analysis of a tissue built with spider silk was developed, taking into account the physical and mechanical properties of this biomaterial and the possible anatomical movements for the anterior cruciate ligament (ACL) for a replacement analysis of this ligament. As result, is concluded that spider silk can tolerate tensile, bending and torsion forces, compared with the mechanical analysis of the ACL, in this way immunological concerns by the action of body fluids and slow incorporation in the human body could be avoided.

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Hardware-in-the-loop simulation and digital control of double inverted pendulum

Germán Darío Buitrago Salazar, Darío Amaya Hurtado and Olga Ramos Sandoval

The popularity that control systems have gained at industrial level, has triggered the use of new technologies to simulate industrial processes in laboratories, without having a station with the plant to control. This paper presents the modeling of an inverted double pendulum and, subsequent emulation and control using Hardware-In-The-Loop. To being able to accomplish the previous, first the mathematical model of the plant was obtained from the method of Euler-Lagrange differential equations. The model was then discretized with a sampling time of 0.2 s and programmed into an embedded device. Within a user interface developed in C#, a discretized LQR controller was programmed acting on the embedded system, through a serial communication protocol. Furthermore, this interface monitors the output signals. The obtained results demonstrate the advantages of using such tools, since a plant can be controlled in real time, without having it physically made.

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Parametric optimization of wire electrical discharge machining process on AISI H13 tool steel using weighted principal component analysis (WPCA) and Taguchi method

Nuraini Lusi, Khairul Muzaka and Bobby Oedy Pramoedyo Soepangkat

Wire Electrical Discharge Machining (WEDM) plays a significant role in the manufacturing process for various industries. In the WEDM process, the objective is always to get improved Material Removal Rate (MRR) along with achieving better surface quality of machined component. An Experimental Investigation was conducted to determine the setting parameters appropriate WEDM process to maximize the material removal rate, minimize kerf and surface roughness of workpiece material. The experimental design used is based on orthogonal matrix L18 design. WEDM process parameters to be determined the setting are the arc on time, on time, open voltage, off time and servo voltage. The results showed have shown that the parameters arc on time, on time, open voltage, and off time have the greatest contribution in reducing the variation of responses were observed simultaneously.

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Flow and heat transfer enhancement around staggered tubes using rectangular vortex generators

Prabowo, Melvin Emil S., Nanang R. and Rizki Anggiansyah

Numerical analysis was carried out to study the flow and heat transfer characteristics around staggered tubes with rectangular vortex generators (VGs) mounted behind the tubes. The effect of location VGs in different span angle from stagnation point (Ф =1200, 1350 and 1400) were investigated in detail while the Reynolds number based on diameter tube was kept constant at ReD=2959. The numerical results are also analyzed from the correlation between the contour velocity and temperature gradients which is a basic mechanism of heat transfer. The results indicated that the rectangular VGs is able to improve the convection heat transfer on the rear part of upstream tube and forepart of downstream tube. The average Nu was shown to increase by 8%-78% and it is found that the location VGs on Ф =1200 provides the best heat transfer augmentation.

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Experimental study of heat transfer characteristics of solar water heater collector with addition wavy fins on pipe

Masykur and Bambang Arip Dwiyantoro

Utilize the potential of solar energy there are two kinds technology already applied, there are solar thermal technology and solar photovoltaic. Solar water heater collector is one of the utilized solar energy. One way to improve the efficiency of collector solar water heating is to add external fins on pipes. This experimental was carried in environment Mechanical Engineering ITS, located in -7.27°LS and -112.79°BT. It is used to cover clear glass with angle of solar collector 10° and flow rate variation 75 l/h, 150 l/h and 225 l/h. Date is collected every one hour from 09.00 am - 15.00 pm for each variation. The measured parameters are upside glass temperature, underside glass temperature, water input, water output, pipe, absorber plate, surrounding, solar radiation and wind speed. The results obtained from this study are the highest efficiency of collector at the flow rate of 225 l/h is 63.87%, and the highest outlet temperature of water at the flow rate of 75 l/h is 46°C. The addition of wavy fins on pipes can improve the efficiency of the collector.

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Effect of composition on the microporosity, microstructure, and macrostructure in the start-up direct-chill casting billet of Al-Cu alloys

Suyitno

Direct-Chill (DC) casting is a process where the liquid metal is poured in a water cooled mold and then the formed solid shell is extracted at downwards and is directly sprayed by water. Almost universally, the cooling medium is water, both for mold cooling (primary cooling) and direct or secondary cooling. Start-up phase is a crucial step during the casting, in which is prone to casting defects such as porosity and hot crack. The aim of this research is to study the effect of copper content in microporosity, microstructure and macrostructure in the start-up phase of DC casting of Al-Cu alloys. The porosity is maximum in the center of billet and maximum at low copper concentration (1 pct). The porosity is minimum in the bottom of billet and it increases for a low copper concentration (1 pct). The grain size depends on chemical composition. Most coarse structure is observed at low concentrations of copper (1 pct). The dendritic arm spacing is unaffected by the chemical composition. The grain size and dendritic arm spacing are predominantly fine in the surface.

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The influence of the addition H₃PO₄ on degradation of glycerol with vibrating horn

Ruslan Kalla, S. Sumarno and M. Mahfud

Indonesia is currently developing a renewable energy-based vegetable oils include the development of biodiesel. One way of making biodiesel is the transesterification process from vegetable oils and ethanol/methanol. The transesterification process will produce primary products such as methyl ester and byproducts /waste in the form of glycerol approximately 10-15 % so that glycerol is quite abundant. Degradation of glycerol were processed by the method of sonication can produce many other compounds include acrolein. The purpose of this study was to determine the effect of phosphoric acid catalyst in the degradation of glycerol. The process of production is done in sonication reactor type 316 stainless steel is equipped with an ultrasonic wave generator. The operating conditions of research are atmospheric pressure with water glycerol mass ratio is 1: 8. Research variable is the temperature of sonication 30, 40 and 50 °C, sonication time is 10, 30, 50, 70 and 90 minutes with and without the use of catalysts. Results of the experiment were analyzed by using Gas Chromatography (GC). The results showed that the ultrasonic wave radiation for glycerol degradation process can be used to produce other compounds such as acrolein and others. With the use of H₃PO₄ catalyst conversion is greater than without using a catalyst and increases with sonication time. The highest conversion obtained with the use of catalysts H₃PO₄ is 72.68 % in the sonication time of 90 minutes and a temperature of 50 °C, while the highest yield obtained was 49.50 % with the use of a catalyst H₃PO₄ at sonication time of 90 minutes and a temperature of 50 °C.

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Effect of variation of Kalium hydroxide solution concentration and temperature to the corrosion resistance of AISI 304, AISI 316, and copper alloys in water electrolysis apparatus

IDA Hamidah, AGUS Solehudin and AGUS Setiawan

The corrosion resistance properties of various metals which were used as electrodes in water electrolysis apparatus had been analyzed. This analysis is important to improve the performance of the water electrolysis apparatus. Stainless steel was used as an electrode in water electrolysis apparatus and it was immersed in KOH solution. KOH solution with various concentrations and temperatures were used to test the corrosion resistance of AISI 304, AISI 316, and Copper Alloys. To analyze the corrosion resistance, calculation of corrosion rate was conducted by using mass loss method. Through the calculation, it was found that the corrosion rate was increased linearly by increasing the concentration and temperature of the solution. This means that the metal has poor corrosion resistance at high concentrations and high temperatures. Among the three metals that were tested, it was also found that AISI 316 showed the most resistant to alkaline environment.

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The role of heterogeneous nucleation in water based phase change material for medium temperature refrigeration

I. M. Rasta, I. N. G. Wardana, N. Hamidi and M. N. Sasongko

This paper presents an experimental investigation on effects of corn oil to ice nucleation phenomenon of a corn oil - water solution immersed in a tank containing super-cooled liquid mixture of water and propylene glycol. Temperature of water and propylene glycol mixture was to be maintained as low as -20 °C. The corn oil-water solution is a new PCM candidate to be investigated for medium temperature refrigeration applications. Thermal energy storage characteristics of the PCM candidate were established and tested at various concentrations using a T-history method. Ice nucleation below freezing point in water/ice at temperatures ranging from -6 °C to -4 °C was induced by mixing corn oil with water to form an oil-water solution. As most of the solution consisted of water, this PCM became a strong candidate for under 0 °C applications. The PCM should be capable to maintain product temperatures of a medium temperature refrigeration system between -1 °C and +5 °C.

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Characteristics of electrode materials on machining performance of tool steel SKD11 with EDM Shinking

Suhardjono

Both qualitative and quantitative performance of EDM Shinking process depends not only on process parameters but also on the combination between electrode material and workpiece material. This research experimented an EDM machining process uses a different type of electrode material such as cooper, aluminum, steel, brass, stainless steel, bronze and graphite to machine a workpiece of hardened tool steel SKD11. Parameters being analyzed in this research are not only the surface quality but also the material removal rate (MRR), the tool wear rate (TWR), the wear ratio (WR) which is defined as MRR/TWR. The result of the research shows that using different electrode material gives the surface roughness differences less than 3 µm e.g. for pulse current Ip=20A and Ignition voltage Uz=150V using the steel electrode and stainless steel electrode gives maximum Ra 9.63 µm and minimum Ra 6.90 µm respectively or between ISO N9 and N10. In the point of view of quantitative performance, the graphite and brass give the two highest MRR that is almost two times higher than the mild steel and stainless steel electrode. However the brass electrode has a tool wear rate 7.8 times higher than the steel electrode or 5.5 times higher than stainless steel electrode. Therefore it has the lowest wear ratio and even less than 1.0 for Ip=45A. The highest wear ratio is shown by stainless steel electrode with WR=5.23 and the lowest one is by brass electrode with WR=0.9. So, it means the brass electrode is eroded faster than the workpiece. In conclusion the application of the graphite and brass electrodes are normally used for roughing and stainless steel electrode is for finishing process.

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Multiple-performance optimization of drilling parameters and tool geometries in drilling GFRP composite stacks using Taguchi and grey relational analysis (GRA) method

Gallih Bagus W., Bobby O. P. Soepangkat and Iwan Krisnanto

Composite materials are used in many applications and are mainly used for structural components. Glass fiber reinforced polymer (GFRP) composite is an economic alternative for engineering materials due to its advantageous properties. Drilling is the one of important operations for composite structure which is quite often used as a final operation before assembly. The objective of this paper is to optimize drilling parameters such as cutting feed and cutting speed, tool geometries such as drill point geometry and drill point angle on the thrust force, hole roundness and hole surface roughness in drilling GFRP stacks. In this research, experiments are carried out as per Taguchi design of experiments and an L18 orthogonal array was used to study the influence of various combinations of drilling parameters and tool geometries on quality of the hole. The optimum drilling parameter is determined by using grey relational grade obtained from grey relational analysis for multiple-performance characteristics. The drilling experiments were carried out by using twist drill and CNC machining center. This work is useful for optimum values selection of various drilling parameters and tool geometries that would not only minimize the thrust force but also reduce the hole roundness error and hole surface roughness, so it can improve the quality of the drilled hole.

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Simulation of two segments crash box subjected to frontal load

Moch. Agus Choiron and Sudjito

This study will simulate the two segments crash box design due to frontal load direction. The parameter of two segments crash box design consists of: connection angle between segments (Θ), connection length (p), segment thickness ratio (t1/t2), segment height ratio (h1/h2) and outer diameter (d_o). Deformation mode of crash box and energy absorbing due to frontal load is observed. Taguchi method was used as design optimization method. Taguchi matrix L18 was selected. Based on simulation results, energy absorbing on two segments crash box is a constant rise on beginning conditions, then it enhance with high slope of the curve on middle condition. This fact is correlated with the pattern of deformation that it occurs in the first segment on the beginning data, then it continued as deformation joining between first and second segment. From the observation of energy absorption capability in the frontal load simulation, it can be concluded that the optimum design is a model design with parameters: Θ = 45°, p = 10 mm, t1 / t2 = 2 mm / 3 mm, h1/h2 = 40 mm / 60 mm and d_o = 75 mm.

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Experimental study the effect of angle of blade inclination on coal swirl fluidized bed drying

Melvin Emil Simanjuntak, Prabowo, Djatmiko Ichsani, Wawan Aries Widodo and Ahmad Sefriko

Boilers in Indonesia’s power plants generally are designed using high range coal. The lack of supply for this coal leads consumption switched to the low range coal that will gives impact to decrease plant performance, increase in pollution, operating and maintenance cost. To face this problem, coal must be upgrading before use in boiler. Drying process is one of method to upgrade quality of coal where swirl fluidized bed drying is one of most efficient of fluidized bed drying. This research was conducted with variation for angle of blade inclination 100, 200 and 300 with drying time 5 minutes. The temperature and RH air dryer inlet was 55 °C and 10.5 % and mass sample was 600 gr. For the five minute period of drying, moisture content was decreased from 25.17 to 10.28 %, 11.47 % and 13.67 % based on air dryer calculation and decreased to 9.57%, 11.20 and 13.77% based on coal measurement. Average mass transfer coefficient was 0.058 m/s, 0.052 m/s and 0.043 m/s respectively. Air dryer temperature at outlet for five minute period of drying was 53.1 °C, 51.7 °C and 50.6 °C and relative humidity was 18.13 %, 15.25 % and 15.16%, respectively.

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Experimental study of electrode selection effects on mechanical properties of underwater wet welded-joints

Nur Syahroni, Imam Rochani and Harfian Nizar

Proper selection of electrodes is a key element to improve quality of underwater wet welded joint. Three different types of electrode for shielded metal arc welding (SMAW) namely E6013, E6019, and E7018 were selected to perform underwater wet welding of the mild steel ASTM A36 plate. Tension and bending test were carried out according to ASTM [4] and AWS D1.1 [5] standards respectively. The yield and the tensile strength of welded joints fulfilled the acceptance criteria. The weld joint using E6013 and E6019 electrodes have satisfied the minimum criteria of elongation, but two specimens of the welded joint using E7018 electrode have failed. Welded joints using E6013 and E6019 have also satisfied the acceptance criteria of bending test, but have failed when using E7018 electrode. The reason why the welded joint using E7018 electrode has failed to fulfill the elongations and bend test might be due to large amount of fine pearlite phase in the HAZ that made the welded joint less ductile.

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Calculation of potential wind power in Indonesia by using high altitude wind energy method

Desmas Arifianto Patriawan and Lusia Permata Sari Hartanti

This paper discusses the potential of wind power with high altitude wind energy (HAWE) method. Wind speed data were taken from South Bone Bay (Sulawesi) and Aru Island (Papua). Data was retrieved using satellite imagery. The data were obtained, then were simulated into wind power with different heights. Differences in altitude will increase the speed of the wind, thereby increasing average power at the turbine height from 10 meters to 400 meters increased by 2.2 times. These results show the potential use of methods HAWE in several areas in Indonesia.

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CFD simulation of plasma leakage and fluid flow on dengue virus infected-endothelial cells

Nur Kaliwantoro, Marsetyawan HNE Soesatyo, Indarto, Mohammad Juffrie, Rini Dharmastiti, Mohammad Tauviqirrahman and Zainal Arifin

Plasma leakage is one of the pathological features in dengue infection and may cause fatal condition to the patients. In this study, the investigations of the plasme leakage and fluid flow around the dengue virus infected-endothelial cells were conducted using computational fluid dynamic (CFD) based on in vitro experiments of HUVEC (human umbilical vein endothelial cell) culture on the permeable membrane. Fluid velocity profiles and wall shear stress (WSS) values were computed in each surface of endothelial cells. Fluid flow was assumed as a fully developed incompressible Newtonian flow. It was shown that the leakage flow occurs due to the increase in the gap between the cell-cell junctions of the dengue virus-infected cells. The peaks of the wall shear stress distribution occur at the cell’s tip, where the cell-cell junction starts its origin.

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The influence of binder variation using eruption Kelud sand on sand mold’ strength, quality and fluidity results on Al-Si metal casting

Poppy Puspitasari, Deby Yangin Drajat, Dewi Puspitasari, Za’im Zarkasi, Muhammad Ilman Nur Sasongko, Rudi Anggoro Kurniawan, Putut Murdanto and Tuwoso

Sand casting carried by medium and large scale industries typically uses commercial silica sand. Natural disaster on Mount Kelud eruption has introduced a new breakthrough in the form of ideas to use volcanic sand foundry sand as a base material for aluminum silica based products. This study, meanwhile, used the experimental method in which, prior to be given the treatment, the specimens were analyzed on the strength of molding sand, disability and ability to cast the metal flow (fluidity), and the quality of Al-Si as casting product. In addition, to observe the defects, tests on surface hardness and microstructure of Al-Si using Optical Microscope and Scanning Electron Microscope (SEM) were conducted. The results showed the best fluidity owned by the eruption of Mount Kelud sand specimens with a variety of bentonite 10% and hardness value at 129.71 HV. The data obtained from the microstructure result revealed that the eruption of Mount Kelud sand specimens with 10% portland cement variations have the pinhole defect size of most small amounting to ± 7 pieces and open grain structure defects ± 117 pieces. In other words, sand Kelud eruption molding sand can be an alternative to the metal casting industry.

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Improved junction temperature measurement for high power LED

Tri Ayodha Ajiwiguna, Hun Sik Han and Seo Young Kim

Peak wavelength and forward voltage methods are widely used to measure junction temperature of LED. However, these methods have an error in the measurement for high power LED caused by high current. In the calibration step, joule heating is not negligible if high current is applied even under low duty cycle. Improved junction temperature measurement by these methods is performed to solve that error. The LED package tested consists of six red LED chips attached on the metal board. The dimension of metal board is 30 mm x 32 mm with 3 mm thickness. When it is being operated, the operating current is 13.5 A with 25% duty cycle and 250 Hz of frequency. The result of peak wavelength method and forward voltage method are then compared. Forward voltage method shows higher standard deviation than peak wavelength method. The results of non-improved and improved measurement are also compared. Non–improved measurement shows the lower temperature. The influence of LED junction temperature to the luminous flux of light emitted is also investigated. Luminous flux tends to decrease while the junction temperature increases.

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An innovative concept to improve the muffler performance using automated mechanical IRIS

Mohammad Ahsan Habib, Ahmad Syed Anwar and Md. Anayet U. Patwari

With the development of modern civilization vehicle noise is become one of the main source of noise pollution to the environment. A lot of research has been done in recent times in the field of acoustic filters and exhaust mufflers in order to reduce the exhaust noise. While using exhaust muffler, a back pressure on engine is always produce. This back pressure represents the extra static pressure exerted by the muffler on the engine through the restriction in flow of exhaust gasses. The back pressure value mainly depends on the muffler design and exit diameter of the exhaust muffler. It has been found that for a constant exit diameter of an exhaust muffler the back pressure varies with the change of the engine speed. Due to this variation of the back pressure, the fuel consumption per unit distance is also varies. An attempt has been made in this study to stabilize the back pressure to a suitable value by using an automated mechanical IRIS. The function of the mechanical IRIS is to provide a variable exit diameter to the exhaust muffler. An automated mechanical system will be integrated with the IRIS, so that the exit diameter will vary automatically depending on the engine speed. It has been found through 3D based CFD simulation that the back pressure remains constant for a wide range of speed of the engine. This will ensure maximum the fuel consumption per unit distance throughout the wide range of speed variation.

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Waste fish oil biodiesel production and its performance in diesel engine

Kusmiyati, Triana Retno Pratiwi, and Tri Wulandari

Waste Fish oil was used as raw material for biodiesel production. Two stages processe, esterification and transesterification were applied to convert waste fish oil to biodiesel. An acid catalyst (H2SO4) and alkaline catalyst were used for catalysts of the esterification and transesterification, respectively. Fish oil, methanol or ethanol, and catalyst were reacted in a three-neck flask at temperature at 60 °C and time of 2 h. The effect of alcohol types on biodiesel conversion showed that the optimum condition (conversion of 66.09%) was obtained using methanol. The density, kinematic viscosity, heating value of fish oil biodiesel were 0.8822 g/mL, 4.741 mm2/s. 9713 cal/g, respectively. The biodiesel was tested on diesel engines to determine the engine torque, power and Brake Specific Fuel Consumption as compared to diesel oil. At lower speed engine of 1200-1400 rpm, the engine torque of waste fish oil biodiesel and diesel oil was higher than that at higher speed engine of 1400- 1500 rpm. Blendings of waste fish oil had higher engine torque than that of diesel oil. Blends fuel of waste fish oil biodiesel had higher power engine as compared to that of diesel oil fuel at speed of 1200-1500 rpm. Blends waste fish oil biodiesel had lower BSFC (Brake Specific Fuel Consumption) as compared to that of pure diesel oil.

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Test equipment design of thermosyphon effects on passive solar water heating system

Caturwati NK, Ipick S, Alief and Aufar

Water circulation in passive solar water heating Systems (SWHS) is caused by thermosyphon effects. Thermosyphon is a physical effect of passive heat exchange based on natural convection, which circulates a fluid without the necessity of a mechanical pump. Heating water in solar water heater panels result a trust for moving water toward higher position due to heating experienced while water flow in heating canals in solar water heater panels. In this study show the arrangement of test equipment that will be used to measure the influence of thermosyphon in solar water heater panels. High water level in the upper tank as high as drain position of solar water heater panels, so circulation of water in the system is caused by thermosyphon effect. The solar water heater panels are used in the experiment has 2 m2 surface area. Four halogen lamps with 500 Watt power each mounted perpendicularly to the position of the solar water heater panels, as the radiation sources. This study tested the thermosyphon effect of tilt angle of SWH pairs at 5°, 10°, 15° and 20°. The experimental result is tilt angle of SWH at 15° have the best thermosyphon effect in passive solar water heating systems.

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The effect of welding time and welding currents on weld nugget and tensile properties of thin aluminum A1100 by micro resistance spot welding

Ario Sunar Baskoro, Hakam Muzakki and Winarto

In this paper, the electric resistance spot welding process was applied to thin Aluminum A1100 used for investigating the micro joining process. Resistance spot welding parameter such as, electrode form, electrode material, voltage and electrode force were stayed constant. This experiment uses different welding time and welding current to identify the optimum welding parameters for maximum joint strength. This paper studies the characteristic of resistance spot welded of an A1100 aluminum thin sheet with 0.4 mm in thickness. Material was cut by ANSI/AWS standard dimension. The performance is measured by tensile shear test and microstructure test. The tensile test was measured in the polymer technology center of BPPT (the research center of Indonesia). The thickness of specimen is 0.4 mm. It has Thermal Conductivity 222W/m-K, Melting Point 643-657.2°C, Solidus 643°C and Liquidus 657.2°C. The effect of welding current and welding time will give better performance, such as nugget weld and tensile properties. The welding time and welding current yield the square of nugget zone size or a hole of the specimen. From the results, the maximum load of specimen of 272N can be achieved with the welding parameters of holding time 10 second, cycle time 1, and welding current 2 kA. This welding result has the 292.1 mm² nugget size, and 107.85 mm2 fracture size. This experiment shows the optimum welding parameters that can be used in micro joining application (thin plate).

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The effect of pretreatment and variety of microorganisms to the production of ethanol from coffee pulp

Tri Widjaja, Ali Altway, Siti Nurkhamidah, Luluk Edahwati, Fibrillian Zata Lini and Fixalis Oktafia

Nowadays, the world is facing fossil energy problems such as the rarity of petroleum and natural gas because these kinds of energy cannot be renewed. Therefore, the discovery of renewable energy source is very important to fulfil the world’s energy requirements that will always increase. Coffee pulp is one of the materials that can be used to produce glucose and xylose. The purpose of this study is to produce bioethanol from coffee pulp by utilized both cellulose and hemicellulose components. Coffee pulp is chosen because its production reached 743 kg/ha and has not been used properly. The compositions of coffee pulp are 63% cellulose; 2.3% hemicellulose; 17% lignin; 11.5% protein; 1.8 to 8.56% tannin and 6.5% pectin. Coffee pulp contains of high lignin, therefore pretreatment must be carried out to lower the lignin. Organosolv method is capable not only to produce large amount of high-quality and relatively pure lignin but also to dissolve most of the hemicellulose. The substrate of organosolv pretreatment has higher cellulose and hemicellulose contain than another alternative method. Alkaline method was used to compare the effectivity between alkaline and organosolv method. Cellulose and hemicellulose which are generated from chemical pretreatment, are being hydrolyzed using pure cellulase and xylene enzyme to be converted to glucose and xylose. Then, continue the hydrolysis to fermentation using variation of Saccharomyces cerevisiae, Zymomonas mobilismutant (A3) and Pichia stipitis to ferment xylose and glucose to be ethanol. From this research, we got the best pretreatment process that was shown in Organosolv pretreatment using 50% (v/v) ethanol with the result 0.20% (w/w) of lignin; 52.24% (w/w) of cellulose and 11.48% (w/w) of hemicellulose. The best result of pretreatment was the one which produce the highest cellulose and hemicellulose has no effect relatively. Cellulose and hemicellulose from coffee pulp hydrolyzed by using mixture of pure cellulose and xylene enzyme at temperature 60°C, pH 3 for 30 hours. Reduction sugar yield obtained from hydrolysis is 0,164 gram reduction sugar/gram coffee pulp. Hydrolysis using 50% ethanol with the mixture of pure enzymes gave the best result as productive as 3.480 reduction sugar/gram cellulose and hemicelluloses. High reduction sugar from enzymatic hydrolysis correlated with high concentration of cellulose and hemicelluloses. Then for the highest yield of bioethanol by fermentation using Saccharomyces cerevisiae is 0,065 gram ethanol/ gram glucose and xylose.

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The use of magnetic flux to the welding of Hot Roll Quench Tempered Steel

Sugiarto, Anindito Purnowidodo, Rudy Soenoko, Yudy Surya Irawan and Achmad As’ad Sonief

Hot Roll Quench Tempered Steel (QTS) is term of hot roll steel which produced by PT. Krakatau Steel with carbon content 0.29 %C that given by martempering treatment. Martempering treatment meant to increase the steel hardness for about 500 BHN, thus it cannot be penetrated by bullet. QTS designed as alternative material for industrial supporting of military tactical vehicles. Martempering treatment has been changed metal microstructure from tough ferrite-pearlite to the hard martensite. The weakness of martensite structure in welding field is low weldability and prone to the delay cracking for post welding. Delay cracking also resulted in defect or initial crack which occur by the rapid cooling in the post welding and the dissolved of inclusion and gas in the welding area during solidification in weld metal. In many researches, high circulation rate of weld pool could improve weld metal structure and HAZ, decrease welding defect and improve the other properties. Circulation rate of weld pool can be increased by enlarging electromagnetic force or Lorenz force (FL). Electromagnetic force can be enlarged by increasing welding current density (J) or increasing magnetic flux (B) as with the equation FL = J x B. In this research, it was conducted by QTS plate welding used MIG welding with gas protector CO2. Welding electric current 140 A was flowed to the electrode wire AWS ER 70-S6 with the average welding speed 15 cm/minute. Magnetic flux was added from outside during the welding by flowing DC current to the solenoid 100 x 100 x 10 mm. The DC current that flowed to solenoid was 0, 3, 6, 9, 12 and 15 Ampere. Those current variations resulted in magnetic flux for 0 mT, 2,4 mT; 3,4 mT; 4,43 mT; 6,43 mT and 9,03 mT. Thermocouple of K type was carbon welded in the distance of 10 mm from welding core to measure HAZ temperature. The result was peak temperature in the distance of 10 mm from welding core getting lower because of outside magnetic flux addition from 0 mT to the 9.03 mT. By taking temperature range of post welding comparison from 400°C to 200°C, it was known that without magnetic flux addition which results the highest post welding cooling rate and getting lower to the magnetic flux addition of 9.03 mT. From the radiography test, it was known that magnetic flux addition could decrease welding defect percentage. The bigger magnetic flux addition resulted in smaller welding defect percentage. The bigger magnetic flux addition also resulted in bigger impact strength of welding area with more ductile fracture.

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Optimization of multiple performance characteristics in EDM process of HPM 38 tool steel using response surface methodology and non-linear programming

Amirul Akbar, Bobby O. P. Soepangkat and Arif Wahjudi

The application of response surface methodology and non-linear programming for optimizing multiple performance characteristic in electro discharge machine (EDM) sinking process of HPM 38 steel was investigated. In this research, the main objective was to minimize surface roughness with electrode wear rate and material removal rate as constraints. The experiments were conducted based on Box-Behnken design (BBD) consisting 27 numbers of experiments. Quadratic model regression of response surface methodology was developed as efficient approaches to determine the optimal machining parameters in EDM process. Analysis of variance was applied to investigate the influence of process parameters (pulse current, gap width, on time and off time) and their interactions on surface roughness, electrode wear rate and material removal rate. A confirmation test was carried out to check the deviation of the predicted (optimum value) with experimental results.

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Structural Design Optimization of Vertical Axis Wind Turbine Type Darrieus-Savonius

Bambang Arip Dwiyantoro, Triyogi Yuwono and Vivien Suphandani

The design of wind turbine is always interesting to be studied. Studies on the optimal structure design of wind turbine have been studied by many researchers but are still continuing up to now. The present study is intended to investigate the optimal structure design of Darrieus-Savonius Vertical Axis Wind Turbine (DS VAWT) type by using numerical simulation method. A small 500 W DS VAWT was investigated in this research. Design modifications were begun with several tasks to find the critical parts of wind turbine, after that the modifications were analyzed and improved according to the source of weakness. Several modifications were simulated: shorten the inner shaft and change the inner shaft material. The simulations results show that the critical part from DS VAWT system is the inner shaft, by shortening the inner shaft, the structure strength will improved significantly. Changing the inner shaft material did not show a great improvement.

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Production of plastic paver block from the solid waste (Quarry dust, Flyash & PET)

Nivetha C., Rubiya M., Shobana S., Vaijayanthi RG.Viswanathan M.E. and R.Vasanthi M.E.

Abstract This paper aims to study the possibility of using plastic waste as a binding material instead of cement in the manufacturing of paver blocks. The study bears on plastics with a Polyethylene terephthalate basis. Plastic waste is carried to melt and mixed with a varying proportion of solid waste fly ash and quarry dust (PET 25-35 % fly ash 25 % and quarry dust 40-50% in weight). The measurements of physical and mechanical properties show that plastic waste paver blocks and these proportion in plastic give s better results than concrete paver blocks.

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A novel approach for energy efficient target tracking in wireless sensor networks

S. Parasakthi

Nowadays, Wireless sensor networks (WSN) are emerging because of advancement in wireless communication and miniaturization of the hardware. WSN consists of composed of a large number of low-cost, low-power, multifunctional sensor nodes to monitor physical conditions, such as temperature, sound, vibration, pressure, motion and etc. The small sensor nodes used in this network perform sensing, data processing and communicating. They are densely deployed in the desired environment. Recent advancement in wireless communications and electronics has enabled the development of low-cost sensor networks. The sensor networks can be used for various application areas (e.g., health, military, home). For target tracking applications, wireless sensor nodes provide accurate information since they can be deployed and operated near the phenomenon. These sensing devices have the opportunity of collaboration among themselves to improve the target localization and tracking accuracies. An energy-efficient collaborative target tracking paradigm is suitable for wireless sensor networks (WSNs). The lifetime of a Wireless Sensor Network (WSN) is generally limited by the battery lifetime of the sensor nodes. In this respect, efficient monitoring of the entire network's available energy is of great importance to take appropriate preventive actions. However, the physical limitations of WSNs, such as limited memory and energy resources, mandate such a monitoring mechanism to have low complexity and minimum energy dissipation. In this paper, a mutual-information-based sensor selection (MISS) algorithm is adopted for participation in the fusion process. MISS allows the sensor nodes with the highest mutual information about the target state to transmit data so that the energy consumption is reduced while the desired target position estimation accuracy is met. In addition, a novel approach to energy savings in WSNs is devised in the information-controlled transmission power (ICTP) adjustment, where nodes with more information use higher transmission powers than those that are less informative to share their target state information with the neighboring nodes. In this project, a target is accurately effectively tracked in terms of energy by implementing MISS and ICTP algorithm. Simulations using Network Simulator demonstrate the performance gains offered by MISS and ICTP in terms of power consumption and target localization accuracy.

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Initialization of optimized K-Means centroids using divide-and-conquer method

J. James Manoharan and S. Hari Ganesh

K-means clustering algorithm is one of the most popular unsupervised learning algorithm that is broadly used to clustering the given data items. The k-means algorithm is one of the commonly used clustering methods in data mining. A number of algorithms have been developed for clustering the data items using K-Means due to its simplicity and efficiency. The final clustering result of the K-Means clustering algorithm highly depends upon the initial centroids, which are selected at random by the user. The difficulty of determining the right number of clusters in traditional K-Means clustering has attracted significant importance especially in the recent years. There are many improvement were already developed to get better performance of the k-means, but most of these methods needed other inputs like threshold values for the number of data points in a data set. In this work, the proposed algorithm can solve the problems of finding initial centroids and assigning data items to proper clusters using divide-and-conquer method. So in proposed method, the initial cluster centers have obtained using divide-and-conquer property after that K-Means algorithm is applied to gain optimal cluster centers in dataset. The proposed algorithm can improve the execution speed of clustering the data items using little number of iterations. With the help of mathematical calculations the proposed algorithm decreases the complexity which we face in k-means clustering algorithm.

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Encrypt - Security Improved Ad Hoc on Demand Distance Vector Routing Protocol (En-SIm AODV)

Mr. B.Karthikeyan N.Kanimozhi and S. Hari Ganesh

Resent days Mobile Ad Hoc Network (MANET) mostly uses reactive on-demand routing protocols where routes are launch only when the node needed. Most of the protocols which one is belongs to this category are not including proper security facilities. A MANET is a collection of autonomous mobile nodes with self-configuring, self-administrating features. The Mobile ad hoc environment is accessible by both genuine network users and malicious network attackers. Packets that are routed during route discovery itself it has to be protected in such a way that it has minimum chance of having a malicious node in path formed. In this paper the proposed En-SIm AODV (Encrypt-Security Improved Ad Hoc on Demand Distance Vector Routing Protocol) is the upgraded version of the SIm AODV (Security Improved Ad Hoc on Demand Distance Vector Routing Protocol) which one comes from the previous work. The proposed work uses the private key encryption and decryption to avoid intrusions.

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Machine learning in network intrusion detection system

K. Umamaheswari and S. Janakiraman

During the last decade, anomaly detection has attracted the attention of many researchers to overcome the weakness of signature-based IDSs in detecting novel attacks, and KDDCUP 99 is the mostly widely used data set for the evaluation of these systems. As network attacks have increased in number and severity over the past few years, intrusion detection system (IDS) is increasingly becoming a critical component to secure the network. Due to large volumes of security audit data as well as complex and dynamic properties of intrusion behaviors, optimizing performance of IDS becomes an important open problem that is receiving more and more attention from the research community. In this paper, we evaluate performance of a comprehensive set of classifier algorithms using KDD99 dataset.

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An innovative security architecture and algorithm for social network services

S. Thiraviya Regina Rajam and S. Britto Ramesh Kumar

Social Network Services (SNS) play a vital role in today s communication. There is a need to ensure the security, effectiveness, usability, friendliness and accuracy mechanisms in SNS. In this paper an innovative Security Architecture and Algorithm for Social Network Service (SAASNS) is proposed. SAASNS System has been developed and implemented to provide web-enabled community SNS. The results are tested for community user authentication and access to services as well as to measure system response time with respect to the user.

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Design and implementation of an interactive query expansion methodology for information retrieval

S. Ruban, S. Behin Sam and Vanitha T.

Information Retrieval is a field of computer science that has seen a tremendous change in the past two decades. After the advent of World Wide Web, access to information became handy because of search engines. An Information Retrieval system consists of the following components i) Query interface where the use poses the information need ii) Index file which is created by the indexing process and the iii) Matching process which finds out the relevant documents from the available index file. The performance of the Information Retrieval system always depends on the above three components. So the improvement in one component can have a significant impact in the overall retrieval performance. In many of the query expansion approaches that are proposed in the literature, the system automatically selects the terms which will be then, be added to the initial query, whereas the user has no control in the query expansion process. Here we propose na interactive query expansion approach where the user gets the help from the system to select the terms that has to be added to the initial query. Our experiments conducted in this regard has also revealed that all the terms generated by the system may not be relevant for expansion but however the user decides which terms to be added and which may not be considered. In this experiment we intend to use a domain Ontology for interactive query expansion and we compare the performance of our system with the traditional one.

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Evaluation of cast iron surface roughness using image processing and machine vision system

N. Nithyanantham and P. Suresh

In recent years, with the beginning of high-speed general-purpose computers and powerful high speed vision systems image analysis have become easier, faster and more flexible. Images of surfaces captured using vision system can be used to identify, analyze and quantify surface texture after the implementation of quality improvement algorithms. Unlike the stylus instruments, the computer vision systems have the advantages of being non-contact and are capable of measuring an area of the surface rather than a single line which makes it a 3D evaluation. In this paper, optical surface roughness parameter 'Ga' has been obtained from an image and is compared with the widely used conventional average surface roughness 'Ra' obtained from the stylus instrument for ground, milled and shaped surfaces.

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Contourlet based biometric watermarking for copyright protection and extraction using ICA

S.Saju and G.Thirugnanam

During the last few decades, there is the continuous development of networking across the globe which simplified their path in data communication, multimedia signal processing and so on. It also ensures there is an effective need of copyright protection in multimedia processing. These data are actually very easy to hack: information becomes vulnerable to interception, copying, tampering or corruption. Many literature s have reported about Discrete Wavelet Transform watermarking techniques for data security. However, DWT based watermarking schemes are found to be less robust against image processing attacks and the shift variance of Wavelet Packet Transform causes inaccurate extraction. In this paper copyright protection for fingerprint image using contourlet transform and extraction using Independent component analysis was proposed. The performance measures like PSNR and Similarity measure are evaluated and compared with Discrete Wavelet Transform (DWT) to prove the robustness of the scheme. Simulations are carried out using Matlab Software.

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Hardware implementation of linear current booster for solar pumping applications

Smrithi Radhakrishnan, Venugopal LV and Vanitha M.

Solar photovoltaic systems have got widely varying characteristics. In order to match the system characteristics with the load, a maximum power point tracking is inevitable. There are several MPPT techniques proposed till date. But the major concern is how efficiently the system works by the inclusion of tracking system with the existing system. In the case of solar irrigation systems, where electric motors are used will be in need of high starting current in early morning and late evenings. The panel may be unable to provide this required power to the motor. In this paper a new technology called Linear Current Booster (LCB) is being introduced which will increase the current by sacrificing the voltage.

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Fuzzy logic control based three phase shunt active filter for power quality improvement in distribution system

P. K. Mani and K. Siddappa Naidu

This paper presents a Fuzzy Logic Control Based (FLCB) Shunt Active Filter (SAF) capable of reducing the total harmonics distortion (THD) in Power System (PS). SAF is one of the key controllers in Flexible Alternating Current Transmission System (FACTS) to control the transmission line voltage and can be used in PS to enhance the power transmission capacity and extend the transient stability. In order to improve the power factor, compensate the reactive power and suppress the total harmonic distortion (THD) drawn from a Non-Linear Diode Rectifier Load (NLDRL) of SAF, we propose a Hysteresis Current Pulse Width Modulation (HCPWM) technique which is used as control for the switches of the Voltage Source Inverter (VSI) or SAF. The synchronous reference D-Q frame theory is used to generate the reference compensating currents for SAF. A fuzzy logic based control is developed to regulate the voltage of the DC capacitor. The system with control scheme is implemented in Matlab/Simulink. The simulation results show the effectiveness of the proposed method for harmonic damping and voltage regulation.

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Simulation and hardware implementation of STATCOM-Dynamic Voltage Restorer (S-D) device

P. K. Mani and K. Siddappa Naidu

Power quality has become an important factor in power systems, for consumer and household appliances with proliferation of various electric and electronic equipment and computer systems. The main causes of a poor power quality are harmonic currents, poor power factor, supply-voltage variations, etc. A technique of achieving both active current distortion compensation, power factor correction and also mitigating the supply-voltage variation at the load side is compensated by unique devices S-D (STATCOM and DVR) in this paper. The proposed S-D system can improve the power quality at the point of common coupling on power distribution systems under unbalanced and distorted load conditions. The STATCOM is connected across the load to compensate for current related problems such as reactive power compensation. The series component of the S-D device is Dynamic Voltage Restorer which inserts a voltage so as to maintain the voltage at the load terminals balanced and free of distortion.

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Survey on speed controllers for a permanent magnet brushless DC motor

B. Gunapriya, M. Sabrigiriraj, M. Karthik and R. Nithya Devi

The permanent magnet brushless DC motors are utilized more in automotive, industrial and household product due to its high torque density, compactness, high efficiency, low maintenance and simple control. BLDC motor is meant to utilize the trapezoidal back emf voltages with square wave currents to come up with constant torque. BLDC motor is electronically controlled and needs rotor position data for correct commutation of the currents even at fixed-speed application. On the other hand it's very important to lower the producing value of the BLDC motor drive for several applications. This survey presents analysis of many algorithms planned by many authors to deal with the speed control of BLDC motor effectively. The several algorithms are analyzed completely to spot their benefits and limitations. The performance analysis of the algorithms is applied to see the simplest approach. Finally the fuzzy and neural techniques are found to have superior quality for speed control of drives.

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Design of PSO-PID controller for a nonlinear conical tank process used in chemical industries

D. Mercy and S. M. Girirajkumar

Conical tank process has become increasingly popular in many industrial sectors like Chemical Industries, Paramedical Industries, Fermentation Industries, Drugs Manufacturing Industries, etc. Conical tank plays a vital role in chemical industries for chemical mixing, chemical storage & waste product draining. It is very difficult to control the level of the conical tank as it has a non-linear property of varying diameter and volume. Hence, it needs a sophisticated method to control the process and the most reliable one is using the PID controller. The PID controller is the generic feedback control technology and it makes up 90% of automatic controllers in process industries and is also the cornerstone for many advance control algorithms and strategies. For regulating the PID Controller, many tuning rules have been enclosed. Though, it provides proper tuning of the PID and it does not provide optimal tuning. In this paper we proposed the conventional tuning, internal model controller tuning and Particle Swarm Optimization (PSO) tuning. The three results are compared based on the tuning values, time domain specifications and error criteria and the best tuning method is identified for a nonlinear conical tank system.

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A novel fuzzy based internal model controller design of a perfusion system for CPB surgery conditions

M. Dhinakaran and S. Abraham Lincon

In a Perfusion System the blood from the patient body is continuously collected and returned through plastic tubing to allow the health care professionals to perform an artificial organ function like Artificial Heart (Blood pump), Artificial Lungs (Oxygenator) on the blood during CardioPulmonary Bypass Surgery. CardioPulmonary Bypass (CPB) is a technique that temporarily takes over the function of the Heart and Lungs during surgery, Heart Lung Machine (HLM) support is used for maintaining the circulation of blood and the Oxygen content of the patient body. HLM system is managed by perfusionist manually to maintain proper blood flow and blood pressure. Much of the time, the perfusionist makes small adjustments in the system to maintain flow and pressure. This maintenance process can be tedious and is prone to human error. So by the introduction of an automatic control, the variables can be perfectly controlled. In this work model identification and controller design of a perfusion system is done by real time Blood Gas Analyzer (BGA) reports collected from various CPB surgery patients. For those values an identified model is estimated and tested in MATLAB. The proposed controller is designed and tested in MATLAB Simulink for CPB Surgery conditions. So this control strategy presented ensures the patient s safety.

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A novel bit serial architecture based K-best decoder for MIMO detection

Shirly Edward A. and Malarvizhi S.

Multiple-Input Multiple-Output (MIMO) systems are widely studied and included in some wireless communication standards in order to achieve tremendous gains in wireless system capacity and link reliability. At the receiver end, Maximum Likelihood (ML) detection has a superior performance but its VLSI implementation is infeasible due to its complexity. Therefore, a modified k-best detection algorithm is proposed and its architectural implementation using Distributed Arithmetic algorithm which is bit serial in nature is presented in this paper. The hardware implementation is targeted to Xilinx Virtex FPGA and the results are tabulated. The comparison of resource utilization with literature shows reduction in hardware complexity to a greater extent. Our design achieves a decoding throughput of 39Mbps.

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Effect of heat and mass transfer on MHD oscillatory flow with chemical reaction and slip conditions in asymmetric wavy channel

J. Sasikumar and A. Govindarjan

In this study, the effects of slip parameter on hydro magnetic oscillatory flow combined with heat and mass transfer in asymmetric wavy channel with species concentration through porous medium having non uniform wall temperature are investigated. Due to the pulsatile flow nature, the dimensionless flow governing equations on continuity, momentum and energy are solved based on some simplifying assumptions. Analytic solutions are obtained for temperature distribution, mass concentration and velocity fields. The features of flow characteristics are analyzed graphically. Results of radiation parameter, Peclet number, Hartmann number and geometric parameters on flow and heat / mass transfer characteristics are discussed. It is observed that velocity profiles increase with an increase in the cold wall slip parameter and decrease for an increase in porous medium parameter.

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An urban road traffic with the dedicated FUZZY control system in VANET

J. Veneeswari and C. Balasubramanian

A intelligent system is embedded on all upcoming devices on working environment to allow the system to think, ease of access and share information .In wireless adhoc networks intelligent transportation system is used improve vehicle communication and safety movement between vehicles with multihop transmission. Feasible outcome of needed data s to take decision in VANET mainly used in urban road topology it contain more mobility of vehicle is present. Incorporating intelligent transport system to provide multiple routing path to know the shortest distance between VANET. Cluster head dope out with position of vehicle more number of vehicles is added to the cluster head. Using fuzzy logic we can eliminate collision and increase packet delivery ratio In this paper FUZZY LOGIC with time based allocation to avoid retransmission of packet and collision rate. It s more feasible to communicate with inter-vehicle by cluster formation with the scheduled time which reduce the network overhead .Performance of fuzzy with time slots are proven with the simulated results.

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Modeling and simulation of modified bridgeless converter and a single phase seven-level inverter for a solar power generation system

J. Sevugan Rajesh and R. Revathi

This paper proposes a solar power generation system, which integrates a modified bridge less converter and a new seven-level inverter with a novel pulse width modulation (PWM) control scheme. High static gain step-up dc-dc converter based on the modified SEPIC converter with magnetic coupling and without magnetic coupling are presented and analyzed. The dc dc converter to specify the size of incremental current in the current command of MPPT. This proposed seven- level inverter is designed using a capacitor selection circuit and a bridgeless power converter, connected in cascade. Proper switching of the inverter can produce seven output-voltage levels (Vdc, 2Vdc /3, Vdc /3, 0,-Vdc, -2Vdc /3, -Vdc /3) from the dc supply voltage. The performance of the proposed maximum power point tracker and seven-level inverter are demonstrated in MATLAB simulation at different operating conditions.

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Improvement of power quality in facility side using modified UPQC (Unified Power Quality Conditioner)

P. K. Mani and K. Siddappa Naidu

The main objective of this paper is to improve power quality in the facility side i.e. distribution side. For that we are implementing most recent FACTS device called Unified Power Quality Conditioner (UPQC). The unified power quality conditioner (UPQC) is a custom power device, which mitigates voltage and current-related PQ issues in the power distribution systems. The proposed topology helps to match the dc-link voltage requirement of the shunt and series active filters of the UPQC. The topology uses a capacitor in series with the interfacing inductor of the shunt active filter, and the system neutral is connected to the negative terminal of the dc-link voltage to avoid the requirement of the fourth leg in the voltage source inverter (VSI) of the shunt active filter. The average switching frequency of the switches in the VSI also reduces; consequently the switching losses in the inverters reduce. And also, the level of harmonics present in the distribution line gets reduced.

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Numerical analysis on 36cm² PEM fuel cell for performance enhancement

Lakshminarayanan V., Karthikeyan P., D.S. Kiran Kumar and SMK Dhilip Kumar

The effect of the various parameters affects the performance of the Proton exchange Membrane (PEM) fuel cell. In this work the various landing to channel width of (L: C) 1:1, 1:2 and 2:2 Multipass serpentine flow channel PEM fuel cell with 36 cm² (6cm x 6cm) effective area was analyzed numerically. The model was developed and simulated under the pressures ranges from 1 bar to 2.5 bar, stepping by 0.5 bar and temperature ranges from 323 K to 353K increasing by 10 K using Creo 2.0 the fluent CFD 14 software respectively. The maximum power densities of 0.658, 0.642 and 0596 W/cm2 were obtained in the L: C of 1:1, 1:2 and 2:2, respectively.

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Emission characteristics of a compression ignition engine using methyl esters of rice bran oil and diesel blends

R. Senthilraja

The emission characteristics of a single cylinder four stroke compression ignition multi fuel engine when fueled with rice bran methyl ester and its 20% and 40% blends with diesel (on a volume basis) are investigated and compared with standard diesel. The suitability of rice bran oil methyl ester as a biofuel has been established in this study. Bio diesel produced from rice bran oil by transesterification process has been used in this study. Experiment has been conducted in various loads such as 0%, 25%, 50%, 75% and 100% at a fixed engine speed of 1500 rpm and at compression ratio of 17.5:1. The impact of fuel blend on exhaust gas emissions has been investigated and presented. The fuel blend which gives comparable emission with the standard diesel has been identified. The blends when used as fuel results in reduction of smoke and carbon monoxide, hydrocarbon comparable with the diesel and increase in nitrogen oxides emissions.

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Influence of nano reinforced particles on the mechanical properties of aluminium hybrid metal matrix composite fabricated by ultrasonic assisted stir casting

Praveen kumar A., Aadithya S. and Dhilepan K. and Nikhil N.

During the past few decades, materials design has shifted emphasis to pursue low cost, quality, light weight, environment friendliness, and performance. Aluminium matrix composites are important class of engineering materials used in aerospace, automotive, engineering, defence and other industries because of their lower density, higher specific strength, and better physical and mechanical properties. Aluminium Matrix composites are projected to significantly reduce the overall weight of the vehicles while maintaining satisfactory structural strength. Reinforcement of micro or nano-sized range particles with aluminium matrix yields improved physical and mechanical properties in composite materials. In this paper, we have investigated the effect of ultrasonic stirring in aluminium matrix composite with micro silicon carbide particles (fixed 5% wt.) and Nano Graphene (1, 3 and 5% wt.). Al356 was used as a matrix material. Micro SiC and Nano graphene produced by reduction of Graphite oxide Method were added as the hybrid reinforcements in varying proportions. Al 356 alloy/ (Graphene + SiC) hybrid composites with different hybrid ratios were synthesized using semisolid stirring assisted ultrasonic cavitation method. For comparison, an Al356 alloy + 5% SiC sample was also casted under the same conditions. Various properties of composites like tensile strength, ductility, Flexural strength, hardness, impact strength were measured and compared with Al356 + 5% SiC sample. The application of ultrasonic vibration on the composite during melting refined the grain structure of the matrix, and improved the distribution of nano-sized reinforcement. From the results of tensile test, it is found that the value of tensile strength increases with increase in Wt. % of graphene. The hardness of composites with 3% Nano graphene is higher than 1 and 5 % Nano graphene. The presence of Nano graphene in Al 356 alloy SiC composites validates the fact that, there is an improvement in mechanical properties.

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Performance enhancement on 36cm2 single pass interdigitated flow channel of PEMFC

Lakshminarayanan V., Karthikeyan P., Aswin C. and Charandeep Singh

In this paper the performance of various rib to channel width of (R: C) 1:1,1:2 and 2:2 Single pass interdigitated flow channel of Proton Exchange Membrane Fuel Cell (PEMFC) with 36 cm2 (6cm x 6cm) effective area with constant mass flow rate of species was analyzed numerically. The effect of the various parameters affects the performance of the PEMFC. The model was developed and simulated using Creo 2.0 the Fluent CFD 14 software respectively. The pressure ranges from 1 bar to 2.5 bar, with an interval of 0.5 bar and temperature ranges from 323 K to 353K increasing by 10 K. The maximum power of 18.1476, 18.774 and 18.0828 W was obtained in the R: C of 1:1, 1:2 and 2:2, respectively.

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Determination of a global action plan to mitigate the fear of mathematics among the engineering students using multi-step FCM approach

Nivetha Martin J., Kaliga Rani and L. Vinotha

Education is a device that designs the life of the mankind. The students of today are very ambitious and in particular the engineering students are much determined to achieve in various domains, but they are bound to many academic constraints. One of the most notable one is the percentage of imbibing the acquaintance of their specialization, with that of the subject mathematics is comparatively very low. The sole reason for their poor performance is fear towards the subject. This emotional aspect disintegrates the channel of learning mathematics. To refurbish the minds of the students a profound investigation has to been undertaken for which this paper is a step towards it. The method of multi-step FCM (Fuzzy Cognitive Maps) approach is applied in this paper to uncover the measures of mitigating the fear of mathematics among the engineering students from the teaching perspective.

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Optimization of process parameters to enhance the mechanical properties of bone powder and coir fiber reinforced polyester composites by Taguchi method

K. Vignesh, G. Ramasivam, U. Natarajan and C. Srinivasan

This study investigated the optimization of the process parameters to enhance the mechanical properties of bone powder impregnated coir fiber reinforced polyester composites using Taguchi method in combination with Grey relational analysis. The factors considered for the optimization are the coir fiber diameter, coir fiber length, bone powder content and bone powder size, each at three different levels. The mechanical properties such as the tensile strength, flexural strength, compressive strength and impact strength are selected as the quality targets. Nine experimental runs based on L9 (34) orthogonal array of the Taguchi method are performed. An optimal parameter combination of the composites is obtained through the Grey relational analysis. The analysis of variance is applied to identify the most influential factor and it is found that the composites. A confirmation experiment is performed to verify the optimal result. The results of the confirmation tests prove that the tensile strength, flexural strength, compressive strength and impact strength of the composite samples enhanced simultaneously through the optimal combination of the composite parameters obtained from the proposed method. The improvement in the tensile strength, flexural strength, compressive strength and impact strength of the composite samples at the optimized condition are evaluated.

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Experimental investigation of dry drilling of Austenitic Stainless Steel

M. Arun, N. Arunkumar and R. Vijayaraj

Austenitic stainless steel is difficult to drill using conventional High Speed Steel tools. Hence Cemented carbide, coating of TiAlN in High Speed Steel and on Cemented carbide drills are investigated in drilling of AISI 316 Stainless steel. Three cutting speeds and three feed rates are used to conduct different experiments. To reduce the number of experiments, Taguchi’s L9 Orthogonal array is used. Different parameters like cutting force, surface roughness, Roundness error and Burr height were ascertained for all the experiments. The experiments shows that HSS-TiAlN required less cutting force for machining, while Carbide- TiAlN had less surface roughness. In case of Roundness error HSS-TiAlN gave less roundness error and for Burr height Carbide-TiAlN had highest burr height.

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Factors influencing submerged Arc Welding on stainless steel- A review

A. Arul Marcel Moshi, S.R. Sundara Bharathi, R. Rajeshkumar and R. Kumar

Stainless Steel have functional characteristics in wide variety of applications such as nuclear reactor vessels, heat exchangers, oil industry tubulars and components of chemical processing units. Components have been used in such industries often required joining of materials with high thickness. There are many welding methods reliable for stainless steel welding. Among various welding methods, Submerged Arc Welding technique is familiar for high thickness welding .In this paper, Submerged Arc welding process and the effect of process parameter on quality of welding have been reviewed with various researches and discussed in detail because of its inherent benefits such as higher metal deposition rate, good strength of the joint and good surface appearance. Due to the above said desired properties, this welding process is extensively used in the fabrication of pressure vessels, pipe lines and off-shore structures. Welding flux constitutes nearly half of the cost in Submerged Arc Welding process. This welding process is often preferred because it offers high production rate, high melting efficiency and ease of automation. The review is concerned with factors influencing the quality of weld in stainless steel by Submerged Arc Welding and hope that it is very helpful for predicting the best welding conditions for stainless steel.

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Electric discharge machining of Al-TiB2 composites with and without graphite powder suspended dielectric

M. Prabu, G. Ramadoss, C. Senthilkumar, S. Magibalan and P. Senthilkumar

The excellent mechanical and physical properties of metal Matrix Composites (MMCs) make them very attractive for a variety of engineering applications and also yielded enormous economic benefits to manufacturing industries through improved product recital and product design. The MMCs presently attracting most interest are those based on aluminum alloys and reinforced with particulate of either aluminum or silicon carbide. Conventional machining of these composites posted difficulties due to abrasive nature of reinforcement which causes severe cutting tool wear. It is therefore essential to develop the technology of non-conventional machining processes which can be effectively used for machining such advanced materials and Electric Discharge Machining [EDM] is an important non-conventional machining process that can effectively machining these materials. EDM process is a hasty recurring spark discharge method, initiated typically between the negative tool and positive work piece, engrossed in a dielectric medium. The dielectric medium used in EDM process serves as a coolant for the tool and work piece, serves as a conducting medium when ionized and conveys spark and also as a flushing medium in removing fragments. When graphite powder is suspended into the dielectric fluid and injecting at the tool-work piece or inter electrode gap during machining, will make deionization easier and lesser the path resistance causing an increased in discharge rate. This work presents some of the investigations in machining Al-TiB2p MMC by EDM. The experiments are conducted on Electronica Spark Erosion Machine. This augments Metal Removal Rate (MRR), decreases Tool Wear Rate (TWR).

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Experimental investigation of machining parameters in electrical discharge machining using EN36 material

M. Panneer Selvam, Ravikumar R., Ranjith Kumar P., and Deepak U.

The quality of a product is the main factor for showing growth of a company. The quality of the product mainly depends upon the material and process parameters. Optimization technique plays a vital role to increase the quality of the product. Hence, many authors have presented their works on the optimization of process parameters for various machining processes. EDM process optimization with multiple performance characteristics based on orthogonal array with copper electrode. The process parameters such as gap current, pulse on time and pulse off time were optimized with the considerations of multiple performance characteristics such as material removal rate, tool wear rate and surface roughness value on the work material.

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Design and analysis of dynamic Electromagnetic Suspension System for improved vehicle stability

M. Suresh, Walter Karg R., R. Rohith Renish and Viraal Nemani

Introducing a new technology ‘Electromagnetic Suspension System’ which works on the principle of ‘Faraday’s law of Induction’. It replaces the hydraulic and air suspensions. Here we bring in the use of electromagnets to push/pull the wheel in and out of a dip without jostling of the car body that will result in easy and safe driving. This system consists of two electromagnets placed inside the cylinder. One of the electromagnet that is placed in the top end of the cylinder is fixed and the other placed in the bottom end of the cylinder is movable. A rheostat that is used for varying resistance is used here. The main purpose of the rheostat is that it could vary current. There is an additional fitting done to the movable end of the rheostat. A strong spring has to be attached to the movable end of the rheostat so that it could come back to its original position. A rod is attached from the jockey of the rheostat to the axle of the wheel. This rod will help the rheostat to vary the current. So when the current is passed to the electromagnets, there will be a repulsive force between them and so whenever there is an upward force acting on the wheel the current has to decrease so that the wheel alone will move up and down. This is the purpose why we prefer rheostat. The rod connected to it will vary and then come back to its original position. EMF is defined as the energy available per unit charge that travels once around the wire loop. Equivalently, it is the voltage that would be measured by cutting the wire to create an open circuit, and attaching a voltmeter to the leads. The maximum stress obtained after analyzing the electromagnetic suspension is 130.307 N/mm.2

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Analyzing the manufacturing procedures of inorganic solar cells

Ananda Selvakumar U., Jegathese C. R., Kings S. and Jaffar M.T.

The need for enhancing the performance and energy conversion rates have led to identify better manufacturing procedures of solar cells. Inorganic solar cells are being very widely used and experimented in various mission critical robust applications like satellites and calculators. Improvements are continuously being attempted to increase the performance of solar cells. There are various procedures to manufacture solar cells with varying performances and more experiments are required to enhance the efficiency.

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Study of machinability characteristics for turning austenitic (316L) and super duplex (2505) stainless steel using PVD-TiAlN Nano-multilayer inserts

Dhananchezian M., Thinesh T., Steven Niketan Paul and Inian Roy A.

In this research work, we have intended to study the machinability of dry turning of austenitic stainless steel AISI 316L and Super Duplex 2507 stainless steel with coated carbide PVD - TiAlN Nano-multilayer. The turning operations were performed at three different cutting speeds (79, 121 and 188 m/min); constant feed rate (0.159 mm/rev) and depth of cut (1 mm) respectively. The effect of cutting speed in cutting temperature, the cutting force, surface roughness, tool wear and chip breaking were analyzed. It reveals that the higher cutting force and poor surface finish were found in the Super Duplex 2507 stainless steel over austenitic stainless steel AISI 316L. It is observed that higher tool wear occur in case of Super Duplex 2507 stainless steel over an austenitic stainless steel AISI 316L. The collected chips of various cutting parameters have shown that friendlier-to-machine chips are obtained when machining austenitic stainless steels over the duplex stainless steel grades. Finally, Super Duplex 2507 stainless steel displays poorer machinability responses.

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Effect of cyclone height on holdup mass and heat transfer rate in solid cyclone heat exchanger-CFD approach

T. Mothilal, V. Velukumar, K. Pitchandi and M. Selvin Immanuel

This work investigates the effect of cyclone height (barrel and cone height) on holdup mass and heat transfer rate in a cyclone heat exchanger using CFD code FLUENT 12. Four barrel height (100, 150, 200 and 250 mm) and four cone height (200, 250, 300 and 350 mm) cyclones were tested in order to find its effect on hold up mass and heat transfer rate from gas to solid particles. Flow field is analyzed using Reynolds averaged Navier stokes equation. RNG k-? turbulence model used to analyze the air flow and discrete phase model (DPM) is adopted to predict the particles tracking in cyclone. Experimental data used for the validation of simulations were obtained from the literature study. Previous works in varying the dimensions of cyclone height does not predict holdup mass and heat transfer rate in cyclone. Result shows that increasing barrel and cone height decreases pressure drop, Maximum tangential velocity and axial velocity increases slightly in cyclone heat exchanger. Holdup mass raises 1.6 - 3.6 % with change in barrel height ranging from 100 to 250 mm and 2 - 5 % with change in cone height ranging from 200 to 350 mm. Similarly with increase in barrel and cone height, heat transfer rate raises from 1.5 - 1.7 % and 1.5 - 3.2 % respectively.

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Studies on the influence of drilling cycle on the surface roughness of the drilled holes

L. Francis Xavier, P. Suresh R. Balaragavendheran, P. Yeshwanth Kumar and S. Deepak

Tool wear is a an major issue and challenging task for engineers since wear on the drill increases the surface roughness, affects the hole quality, decreases the tool life and also increases the production cost. As one third of the metal removal process performed in industries is drilling operation, in this paper an experimental investigation was conducted to analyze the influence of drilling cycle on the surface roughness of the drilled holes during drilling deep through holes on the prepared aluminium metal matrix composites. The composites were prepared by using stir casting method. The experiments were carried out both in wet and dry condition using cobalt coated ?5mm HSS drill.G83 peck drilling cycle and G81 drilling cycle was selected to drill deep through holes on the prepared aluminium metal matrix composites.

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Design and Fabrication of advanced aerial robot Quadcopter

N. Tamilselvam, P. Abirami, S. Logasundari, P. Azhaguraja, P. Banumathi and B. Malarvizhi

This paper explains about the Fabrication of aerial robot Quadcopter with advanced avionics system for the use of spraying pesticides and fertilizers in agricultural land. Construction of Quadcopter with multi rotor setup will be most promising task for the unmanned aerial vehicle designers. The fabricated vertical takeoff and landing aerial robot Quadcopter has four motors mounted on its four arms. Brushless motor of 1000 to 1500 rpm and propeller of 10×4.5 have been inbuilt with this Quadcopter for obtaining range up to 700 meters. The Experimental flying test of advanced aerial robot Quadcopter is carried out and it can lifts up to 4kgs weight as a payload.

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Navigation systems in NOE flight sensors and their integration

N. Tamilselvam, D. Divya priya, B. Rajeswari and N. Siddika

This project presents the optimization method for Nap-of-the-Earth. The Nap of the Earth (NOE) mode is the most exciting, most dangerous, and is typically the slowest. It is used by military aircraft to avoid enemy detection and attack in a high-threat environment. NOE is used to minimize detection by the ground-based radar, targets and the control system. The Radar Altimeter or Terrain-Following Radar system, Terrain Awareness and Warning system is used to detect the obstacles during flying in NOE flights. Here, while the flight is at nap of the earth operation, the speed and the altitude must be slow as already determined. The terrain following radar maintains the altitude from the ground level. So we analyze the problem to increase the performance of the aircraft by ranging the terrain by some modes of the Terrain Avoidance and Warning System which is given by ICAO, UKCA, EASA, and FAA. Further to this, different TAWS modes of operation, explanation of mode selection and advancement in TAWS are explained in detail. In this paper, MATLAB programming is done for some modes of TAWS operation and the simulation of flight path for the excessive terrain. Closure rate from mode 2 operation of flight is also done.

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Effect of particles density on holdup mass and heat transfer rate in solid cyclone heat exchanger

T. Mothilal and K. Pitchandi

This work presents the effect of particles density on holdup mass and heat transfer rate in solid cyclone heat exchanger. Performance of cyclone heat exchanger mainly depends on operational parameters such as inlet air velocity, temperature; solid particles feed rate and density. Present work studies the effect of particles density by varying inlet air velocity and temperature. Four different solid particles (Sulfur, Dolomite, Steel and Copper) density ranges from 2050 to 8950 kg/m³ which are fed at 0.5 g/s flow rate and inlet air velocity ranging from 4.6 to 24.2 m/s at three inlet air temperatures 373, 473 and 573 K. Experimental setup was built for stairm and high efficiency cyclone. Good agreement was found between experimental and literature pressure drop. Results conclude that holdup mass and heat transfer rate increases 0.5-1.5% and 82-86% with decrease in density particles respectively. Increase in inlet air velocity, holdup mass and heat transfer rate raises 3.2-6% and 4 - 6.7% respectively for all particles at all inlet air temperatures.

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Aging behavior in Co-Cr-Mo-C alloys

Alfirano, Anistasia Milandia and Suryana

The effects of the addition of 1 wt. % Si and 1 wt. % Mn in Co-28Cr-6Mo-0.25C alloys on phase of precipitate during aging at 873-1473 K have been investigated. The precipitation in the Cobalt matrix was observed in the aged specimens. The result shows that the precipitation consists of fine precipitation of M23C6 type, h-phase and s-phase. Meanwhile, the addition of Si increased the precipitation area in the Time-Temperature-Precipitation (TTP) diagram as compared to the Mn. The addition of Si increased the precipitation area of h-phase. During aging, precipitate size decreased with decreasing aging temperature. Blocky and rod-like precipitates were observed at higher and lower aging temperatures, respectively. The addition of Si increased the hardness of alloy that might be caused by the formation of fine M23C6 type and h-phase precipitates at 1073-1173 K.

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The production study of bipolar plate from cuprum-carbon nanocomposite in polypropylene matrix (PP) for the fuel cell application

M. Fitrullah, A.H. Yuwono and Sari Katili

This research is to get the parameter correlation in synthesis, micro/nano structure processes, and the candidate performance of inorganic-organic nanocomposite from the cuprum and carbon nano particles in polypropylene matrix. Besides, it also aims to get the optimal composition and evenly spread disparity/distribution from the cuprum and carbon particles in polypropylene matrix. To achieve the goals, it is conducted by two processes. The first stage includes the nanocomposite candidate fabrication with the increase of cuprum nanoparticle (0; 0, 5; 1; 1, 5; and 2 wt%) in polypropylene matrix. This cuprum nanocomposite candidate is characterized by the UV-Spectroscopy test, electrical conductivity test, the melt flow rate (MFR) test, the scanning electron microscope test (SEM), and thermal gravity analysis (TGA) test. And the second stage includes the cuprum and carbon nanocomposite candidate fabrication (5; 10; 15; and 20 wt%) with the wet chemical technique. From the research, it can be known that the cuprum nanocomposite (PP-Cu), the optimal composition is achieved in the level of nanocuprum inorganic fulfillment of 2 wt%, which it has the electrical conductivity of 9,306 x 10-9 S/cm with the lowest band gap energy value of 3.78 eV and the highest critical temperature of 3380C also the increase of MFR value reaches 91.09 g/10 minute. Then, for the cuprum and carbon nanocomposite resulted in the second stage, the optimal composition is achieved at 20 w% of black carbon, has electrical conductivity of 5,590 x 10-8 S/cm with the flexural modulus of 1650 MPA and also the melt flow rate (MFR) value of 16.75 g/10 minute which meet the requirement for the missal production by the moulding injection tools.

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Engine test stand layout and post processing tools for the detection of engines’ performance parameters

Marco Bietresato, Massimiliano Renzi, Simone Mischiatti and Fabrizio Mazzetto

An eddy-current brake, capable of measuring the torque and the power of internal combustion engines at desired rotational speeds, has been fully interfaced with an external NI cDAQ 9178 data logger. Thanks to this system, it is possible to collect and synchronize the data coming from the test stand and from several other sensors equipping the motors under test: a load cell used in a chrono-gravimetric fuel consumption system, many thermocouples, a lambda probe, an exhaust gas analyzer. To have a better control of the position of the throttling valve during the trials (hence a higher repeatability), a control system, based on an Arduino board, directly acts on the valve through a servomotor. Then, a series of software tools allows the interfacing of the various devices and the automatic post-processing of the acquired data (filtering of signals, recognition of data corresponding to the single engine speeds, time-averaging). The described testing equipment and the implemented procedures allow investigating, on the whole operating range of a motor (i.e., at different engine speeds and loads), each single performance parameter’s value, such as: the torque, the power, the fuel consumption of the motor, the temperature and the composition of the exhausts (up to nine different gases), the temperature of the engine head and of the cylinder block, the combustion quality and many other additional parameters describing the engine performance. This test stand, with the described post processing procedures, will be used in future works to evaluate the performance of traditional and alternative-fuelled internal combustion engines for both agricultural and co-generative applications.

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Strength analysis of Zno-Al₂O₃ nanocomposite for implant material innovation

Poppy Puspitasari and Andoko

Nowadays, implant material become an attractive attention for the researchers to look for alternative materials that better than the previous material. Several complaints have been found due to the use of titanium and steel as implants in the knee. Composite is the main option and being the center of attention and nanomaterials are a promising new breakthroughs. This study offers a new solution for the knee implant in the form of ZnO-Al₂O₃ nanocomposite as knee implant material. Before being applied to the world of orthopedics, the nanocomposite has been tested using a mechanical testing using hydraulic press machine and has done the compressive strength and shear simulated using software simulation with Catia Version 5 Release 17 (V5R17) and ANSYS. The results of the compressive strength of composites with different percentage comparisons showed that 50% ZnO and 50% Al₂O₃ has the highest compressive strength compared to other composition ratio (80-20 and 65-35). Based on simulation data, ZnO-Al2O3 nanocomposite has the highest strength on the composition ratio of 50% ZnO and 50% Al2O3 which has the ability to withstand a compressive stress of 3 GPa, equivalent to 300 x 107 N / m².

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CBPR: Case based pattern retrieval- A framework for pattern retrieval

Kumar K. and Saravanaguru R. A. K.

Nowadays, existing patterns are available in the form of catalogs. These catalogs, however, they are always searched by a pattern name. Searching for patterns using their name is useful for only experienced analyst who already knows what patterns they need. Inexperienced developers, on the other hand, may have to spend time to read throughout each pattern description before they can find the right patterns. So it is necessary to have systematic framework to help inexperienced developer to search for appropriate pattern based on their design problems. The proposed system addresses the problems which are mentioned above. It uses the case based reasoning techniques to retrieving the patterns and uses formal concept analysis for organizing the cases (design problems). Along with this case weight is added to intent (keywords identified from the problem) so that the ranking efficiency of the system can be improved. CBPR based tool has been adopted the proposed framework and compared with three types of applications.

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Effect of heat treatment on the fatigue behavior of EN8 steel

M. Senthil Kumar, S. Ragunathan and V. R. Srinivasan

Rotary elements exhibit the fatigue failure due to the insufficiency of fatigue strength. EN8 steel was investigated through various heat treatment processes for its fatigue behavior as it finds core application on the production of transmission shafts, crankshafts and gear. Nitriding was influenced to base metal specimens at the temperature of 5600C in cyanide salt bath. The specimens undergone with induction hardening experienced the electrical input of 32kW at 1800C. As combined heat treatment exhibits better output in fatigue strength, the nitrided specimens were introduced induction hardening with 80 KHz frequency. Hardness test and Tensile test were carried out. Rotary Fatigue testing was done in Cantilever type Fatigue testing Machine. Results indicate that Improved fatigue strength was attainable by the combined heat treatment process of Nitriding followed by Induction hardening. Fracture study was done using SEM.

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Numerical solution for image reconstruction in diffuse optical tomography

K. Uma Maheswari, S. Sathiyamoorthy and G. Lakshmi

Diffuse optical tomography (DOT) is a Bio-medical imaging technology used in clinical diagnosis that employs the scattered light to probe the optical properties of human tissues. To reconstruct an image by estimating the scattering and absorption coefficients, the inverse problem of DOT is applied. Diffuse optical tomography suffers from severe ill-posedness caused by noise and incomplete measurement data; hence its efficient, stable and accurate treatment is very challenging. So these parameters are processed by the Levenberg - Marquardt regularizing reconstruction method. It is the standard regularization technique for non-linear least square problem and it is used to overcome the ill-posedness of the inverse problem. The diffuse optical tomography is used in brain and breast cancer for earlier detection of carcinoma cells.

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Visible Light Communication based smart parking system using MSP430

Abinayaa B. and Arun Raja A.

A major issue in public places like shopping malls, museums and hospitals is parking. Parking is the main service used by the people in these private units. The management of these public units invests more time and money in designing parking systems. Existing parking systems are equipped with appropriate sensors and controllers to count the parked cars automatically, but it does not indicate empty parking slots. These systems consume more power and tend to wireless interference. The proposed system, namely, Visible Light Communication based Smart Parking System introduces Visible Light Communication, a data communication technology using a low power MSP430F5529 microcontroller to help drivers to get real-time parking information. Real-time information on free parking slots helps drivers to save time and reduce fuel consumption. Visible Light Communication (VLC) or Li Fi or Optical Wireless technology means the wireless data transfer using LED. Wireless interference is greatly reduced by using VLC. The proposed system is suitable for multiple floor buildings, which involves data gathering from parking side modules integrated in multiple floors of the building. Parking side modules continuously collects the data and intimates the module integrated in the vehicle section. The module in the vehicle section interfaces a GSM modem to send the detected information to the user mobile. The result of the proposed system is validated in an indoor environment.

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Certain investigations and the comparative analysis on the delay logic used for complex adders and multipliers for the reduction of static power consumption

N. Deepak, R. Bharani Kumar and Ashwini A. Metri

For the full custom ASIC design, it is mandatory that every part of the system consideration has to be fulfilled with all the design specifications. In this delay in the complex circuits is an important aspect that has to be considered. In this paper, a comparative study and analysis of constant delay (CD) logic and the static logic is performed for various adders. This logic can also be applied for the CORDIC algorithm circuit that minimizes the delay in the circuit. The CD logic works with the pre-evaluated outputs that are much before the inputs that are fed to the respective stage. This gives an advantage over different styles of design when it comes for the multistage blocks. This control over the delay in the logic helps in the reduction of static power consumption at the different levels. Thus a power controlled design is also achieved along with the reduced delay. A comparative analysis of CD and static logic is been performed for different kind of adders like half adder, full adder, 16 BIT ripple carry adder and 16 BIT Wallace tree multiplier. The analysis is carried out in 120nm technology with frequency as 500 MHz and at a temperature of 450C.

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Compact graphene field effect transistor modeling with quantum capacitance effects

Arya Raj K. and Bala Tripura Sundari B.

A scaled down graphene field effect transistor (GFET) has been modeled by incorporating the quantum capacitance effects. The proposed GFET model scaled down to 90nm has been developed using compact model equations. Metal oxide gated compact GFET models have been modeled without considering variation of top gate capacitance with quantum capacitance effects. But the effects of deviation of quantum capacitance become more with scaling down and cannot be neglected. In this paper the compact drain current equation has been derived by incorporating the dependence of quantum capacitance on the channel voltage and on intrinsic parameters of the device has been considered. The parameters of interest for circuit design have been determined from current characteristics, transfer characteristics, trans-conductance, and transit frequency. As the measure of performance of the model library in a circuit is often defined as unit gate delay, we propose to determine the rise time and fall time of a single GFET inverter and present the results.

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Design of logarithm based floating point multiplication and division on FPGA

N. RamyaRani, V. Subbiah and L. Sivakumar

Logarithmic number systems (LNS) find many of its applications in the field of multimedia, digital signal processing, scientific computing and artificial neural networks due to logarithm and antilogarithm elementary functions. In this paper, logarithm based single precision floating point arithmetic units are designed based on look-up table method that computes various functions like log, antilog, rounding and exponential terms. This paper is focused in the efficient design of logarithmic floating point multiplication and division. Compared to conventional floating point arithmetic units, this work presents the design by using the same hardware for performing logarithmic operations, antilogarithm, rounding and exponential functions. Hence this work is found to be efficient in terms of area and speed compared to the design of conventional floating point arithmetic designs. Synthesis results were obtained in Xilinx SPARTAN and VIRTEX FPGA devices. Comparative results were presented for conventional floating point arithmetic units and log LUT based arithmetic designs.

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Energy management of a hybrid power system for variable speed wind turbine and varying temperature

J. Karthika, V. Subbiah and A. Litle Judy

This paper deals with Energy management of a wind and solar hybrid generation system for interconnection operation with electric distribution system. This system consisting of a Permanent Magnet Synchronous Generator (PMSG), Solar PV, hybrid energy storage, a dump load and an interfacing grid. The hybrid energy storage consists of battery storage and a super-capacitor where both are connected to the DC bus of a system. An energy management algorithm (EMA) is proposed for the hybrid energy storage with a view to improve the performance of the battery storage. Moreover, high reactive power demand makes it more challenging due to the limitation of reactive capability of the wind generating system. A synchronous condenser is employed to provide reactive power. A coordinated control approach is developed to manage the active and reactive power flows among the components. In this regard, individual controllers for each system component have been developed for effective management of the system components. The simulation is carried out using detailed model in MATLAB/SIMULINK model. The performance of the model demonstrated that the proposed method is capable of achieving: a) Good voltage and frequency regulation, b) Effective Management of the Hybrid Storage System, c) Reactive Power Capability by the synchronous condenser.

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Three phase uninterruptible power supply based on trans Z source inverter

Radhika A., Sivakumar L. and Anamika P.

UPS with traditional inverter requires additional step up transformer to boost the voltage. Due to the presence of step up transformer, the inverter current is much higher than the load current, this causes high stress across the switches. This paper proposes a new topology of uninterruptible power supply (UPS) by using a Trans Z-source inverter. The Trans Z source inverter solves this problem with reduced switching stress. Here the impedance network (two inductors with one capacitor) is placed in between battery and the inverter. Compared to traditional inverter, the Trans Z Source Inverter produces high voltage. Further, it reduces the current ripple. The simulation model of a 3-Kw UPS with the Trans Z-source inverter has been developed and verified.

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High level synthesis for design space exploration

Ranjini Krishnanunni K. and Bala Tripura Sundari B.

In VLSI, design space exploration considering various constraints complex using conventional RTL design flow. The techniques of high level synthesis are useful in abstracting the design to a higher level than in the regular RTL design flow. The various hardware architectures possible need to be explored to bring out the design trade-offs in terms of parameters namely latency, critical path delay and resource utilization. The focus of the work presented here is to explore systolic array mapping methods with and without HLS transformations. Unfolding and pipelining are the HLS transformations applied on the DSP benchmark –FIR filter. Unfolding enhances the possibilities of concurrency in loops and pipeline architecture makes concurrency possible. Vivado HLS tool is used to explore the design space for random subspace mapping and computational subspace mapping and analyze their merits and demerits in terms of the design trade-off performance parameters when the design is mapped to Zynq architecture.

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Fatigue behavior of Ni-Zn composite coating on EN8 steel by pulse electroplating

M. Senthil Kumar, S. Ragunathan and M. Suresh

EN8 steel has an important application on production of rotary elements like transmission shafts, crankshafts and gears. The base metal EN8 was exposed to Nitriding in Cyanide salt bath with 5600C temperature. Ni-Zn coating was done on both Nitrided and Non-Nitrided EN8 specimens by pulse electrodeposition. The results of Tensile, Hardness and microscopic tests were studied. Fatigue behavior of each category was studied through Cantilever type Rotary Bending Fatigue machine. Results showed that coating on nitrided specimens produces high fatigue resistance than coating on non-nitrided specimens. Failure mechanism was investigated through SEM analysis.

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Industrial process monitoring and control using Raspberry Pi

Darshini B. and E. Esakki Vigneswaran

Now-a-days the accidents in the coal mine industries have increased. Even if any explosion occurs it can’t be easily known to the labourers and it may cause accidents. So in order to avoid this, a robot has been designed and this robot is allowed to monitor the ambient situations inside the coal mine industry. Some of the environmental parameters such as methane leakage, temperature, oxygen are sensed by using the high end sensors and the sensed data are transmitted to the mobile phone through Wi-Fi. A static ip address is configured in the microprocessor for the Wi-Fi. The robot has a camera that transmits live video signal to mobile phone for monitoring the status of the coal mine and to control the robot movement. If the temperature exceeds a threshold, the cooling fan is automatically set to ON and if any gas leakage is detected the workers are given alert through a buzzer. Oxygen is supplied is there is suffocation for the labourers. The robot is designed using a Raspberry Pi 2 board. The Wi-Fi dongle and sensors are attached to the robot and this robot is tethered with the mobile phone and can be controlled from a web browser using navigation buttons. By this the human intervention can be avoided inside the industry and the accidents can be prevented.

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