A novel sugarcane bagasse derived nano magnetic adsorbent composite (SCB-NMAC) was successfully prepared for the removal of Cu2+ in aqueous solution. Characterization of the newly prepared material was obtained through SEM, EDX, particle size analyzer and XRD. Results confirmed the presence iron oxide coating onto the material. The removal of Cu2+ by SCB-NMAC obeyed the pseudo second order reaction (R2 = 0.982) as opposed to intra particle diffusion (R2 = 0.708), and pseudo first order (R2= 0.402) model. Langmuir isotherm was found to be more applicable (R2= 0.996) rather than the Freundlich isotherm (R2= 0.979), which indicated a monolayer adsorption between Cu2+ and SCB-NMAC. The maximum adsorption capacity was calculated as 113.63 mg/g at pH 4. In addition, adsorption-desorption studies indicated that SCB-NMAC displayed high stability for regeneration with good reusability with desorption efficiency up to 60% and reusability efficiency up to 80% for the three recurring cycles.

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Corn variety may result different phytochemical contents which in turn influence their antioxidant activities. In Indonesia, corn silk has not been utilized. Therefore, we evaluated the radical scavenging activity of (1) corn silk extracts obtained from different solvents possessing different polarity, and (2) corn silk extracts from five different corn varieties. In order to perform the experiment, firstly, the selected corn silk was extracted with four solvents possessing different polarity (water, ethanol 70%, ethanol 96%, ethyl acetate). Following the extraction step, the polyphenol content in the extract was determined. From this study, the highest total phenolic content in the extract was exhibited by ethanol 70% (4.4 mg GAE/g) while it was not detected in the ethyl acetate-based extract. Additional test was performed to determine the total flavonoid content. Similar to previous finding, ethanol 70% performed the best solvent with total flavonoids reached 695 mg RE/g. Secondly, ethanol 70% was then employed to extract phenolic content in corn silk from five different varieties (P11, P21, P27, DK85, DK88). The extracts were subjected to determine their total phenolic content and radical scavenging activity. The results show P11 exhibited the highest total phenolic content (1.58 mg GAE/g) while other varieties shown similar content (0.8-1 mg GAE/g). Accordingly, the corn silk extract of P11 performed the highest radical scavenging activity with % inhibition of 78. It can be concluded that corn variety contributes significantly to the phytochemical contents that influences their ability to neutralize free radical compounds, and it is beneficial for further development of functional food.

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Presently, in Nigeria orange peels are discarded as wastes after consumption of edible parts of orange fruits. However, the country depends on imported essential oil for use in industries for manufacture of products ranging from food, to beverage, cosmetics and pharmaceuticals. This research work was carried out to demonstrate the utilization of orange peel in the production of essential oils by employing different extraction methods. The methods considered in this work were steam distillation, water distillation and solvent extraction. For solvent extraction, Design Expert 7.0 was used to design experimental runs because of its relative popularity among the extraction methods. After the extraction, the oil was analysed to determine its physical and chemical properties. From the results obtained, it was discovered that the orange peels could give the maximum yields of essential oil to be 4.40%, 3.47% and 2.536% when steam distillation, water distillation and solvent extraction were employed, respectively, and that was an indication that the highest yield of essential oil was given by steam distillation among the methods considered. It was also discovered from the analysis of variance carried out on the results of experimental design done for solvent extraction method that a modified cubic model was able to represent the extraction process well with because the model was obtained to be significant, and its square of correlation coefficient was reasonably high. Furthermore, the analysis of variance of the developed model revealed that the significant factors of the process were extraction time and extraction temperature. The characterization of the extracted oil gave its physical and chemical properties values that indicated that it could be used for production of other valuable products in different process industries.

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The openings of refrigerator machine room play an important role in enhancing the heat dissipating performance of the refrigerator compressor. In this study, the compressor housing temperature, the ambient temperature of the compressor and the rotating speed of the fan were measured through experiments. The convective heat transfer coefficient on the compressor housing was then numerically optimized considering various opening shapes. The results show that the convective heat transfer coefficient of the optimized openings increased by about 7 W/m2oC compared to the completely enclosed machine room. Such enhanced convective heat transfer coefficient can contribute to lower superheat of the compressor by efficiently dissipating the internal heat of the compressor.

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The remarkable partial collapse of the Ronan point apartment tower in 1968 initiated an intellectual discussion among the engineering community on the possible ways to design buildings against such catastrophic progressive types of failure. There are, in general, three alternative approaches to designing structures to reduce their susceptibility to disproportionate collapse such as redundancy or alternate load paths, local resistance and interconnection or continuity from these one or more approaches should be used to avoid progressive collapse. For this study, we consider, simple, low rise three-dimensional steel frame is to be prepared using Etabs 2015 software and are designed according to the Indian Standard Codes, for all load combinations. This model is to be an analysis for progressive collapse analysis as per latest GSA guideline 2013. The main objective of this study is to determine and understand the critical locations of columns in three-dimensional steel frames, which will cause the structure to undergo progressive collapse or maximum damage. The location of column removal largely affects the joint displacement and deformation behavior. Nodal displacement of joint changes abruptly, which indicates that beam-column junction becomes critical. Out of two location corner column removal is more critical as compare to Edge middle location due larger cantilever effect and less connecting members present to transfer extra load. Sudden increased in Shear force and Bending Moment values indicate increased the strength of Beam to avoid the progressive collapse in a structure. The alternative path method would be one of the best remedies or precaution to overcome the progressive collapses apart from the other methods mentioned by various researchers in the past.

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The study aimed to find a model of sandy clay erosion rate stabilized with emulsion asphalt. The soil sample was collected from Manuju Village, Gowa Regency of South Sulawesi Province, Indonesia (E.1190 41.035’, S. 050 17.509’, + 269 m). The emulsion asphalt was collected from PT. Widya Sapta Colas. The test method was done by rain simulation using Rainfall Simulator. The research parameters comprise rain intensity (50 mm/hr; 65 mm/hr; 80 mm/hr), acclivity degrees (100; 200; 300), and emulsion asphalt volume (0 cc/m2; 60 cc/m2; 80 cc/m2; 100 cc/m2) with the length of storage 3 days. The model of analysis was dimension method. The analysis of results was descriptive quantitative from the regression and correlation parameters of erosion rate with rain intensity, slope degree, and emulsion asphalt volume. The results of the study indicate that the erosion rate increased exponentially in line with the increase of rain intensity and linearly by the increase of acclivity, but decrease exponentially by the increase of emulsion asphalt volume.

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Implementation of preloading and reinforcing of bamboo grids on peat is expected to reduce compression and increase and bearing capacity of peat soils. Preloading can be applied by using a embankment material that can speed up compression, while to increase the bearing capacity due to embankment load can use a combination of reinforcement of bamboo grids and piles. Modeling was conducted in the laboratory by using peat soil media. The preloading model was conducted with embankment model using iron scrap on peat soil, which were supported by bamboo grid and pile with diameter of 2 cm with length of 20 cm, and spacing of 20 cm and 10 cm. The increase of bearing capacity due to reinforcement can be seen from the settlement and deflection behavior of both peat with bamboo piles and without piles will be discussed in this paper.

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The paper focuses on modelling and simulation of a 5 MW wind turbine with doubly fed induction generator (DFIG) in full load operation. The wind turbine model is described mathematically and presented in simulation blocks. Through a computer simulation, the wind turbine behavior in full load operation is investigated. A speed controller is used to adjust the pitch angle of a rotor blade in high wind speed to limit the wind energy captured by the turbine to the nominal power value. By adjusting the pitch angle to 18.26° at wind speed 20 m/s, the wind turbine is protected from mechanical damage due to torque and power limitation. The simulation results obtained can be used as references for future optimization for the variable speed wind turbine operation.

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Usually a buffer layer of cadmium sulphide is used in high efficiency solar cells based on Cu(In,Ga)Se2(CIGS). Because of cadmium toxicity, many investigations have been conducted to use Cd-free buffer layers. Our work focuses on this type of CIGS-based solar cells where CdS is replaced by a ZnS buffer layer. In this contribution AFORS-HET software is used to simulate n-ZnO:Al/i-ZnO/n-ZnS/p-CIGS/Mo polycrystalline thin-film solar cell where the key parts are p-CIGS absorber layer and n-ZnS buffer layer. The characteristics of these key parts: thickness and Ga-content of the absorber layer, thickness of the buffer layer and doping concentrations of absorber and buffer layers have been investigated to optimize the conversion efficiency. We find a maximum conversion efficiency of 26 % with a short-circuit current of 36.9 mA/cm2, an open circuit voltage of 824 mV, and a fill factor of 85.5%.

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Catalysis of used cooking oil (UCO) transesterification by whole-cell lipase produced by solid state fermentation (SSF) of agro-industrial wastes makes overall biodiesel synthesis greener, economic and sustainable. In the present study, Aspergillus niger KY401431was isolated from butter and identified based on 18S rRNA gene homology. Optimization of several biodiesel synthesis process stages including SSF conditions for A. nigerKY401431 whole cell lipase production and UCO transesterification reaction conditions was carried out. Optimum SSF conditions, based on A. niger KY401431 biodiesel synthesis ability from UCO, were: a combined substrate of wheat bran (WB) and sesame meal (10/0.3, w/w), initial moisture content of 90%, initial pH of 8, inoculums size of 5x 107 spores/g substrate and incubation at 30oC for 6 days. Whereas, the best conditions for UCO transesterification were: 10% (w/w of UCO) biocatalyst, 3:1 methanol/UCO molar ratio with three-step additions at 0, 24 and 48h, 20% water (w/w of UCO), 30°C reaction temperature and reaction time of72 h. Under optimized process conditions, UCO conversion to fatty acid methyl esters (FAME) was improved by about 5-folds, producing a final biodiesel yield of 75.5%.

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Regenerative shock absorber has been developed and investigated widely since last two decades. Several methods have been studied to acquire maximum regenerated electric power, better efficiency and to maintain its performance close to the conventional shock absorber in providing vehicle ride quality. In this paper, a novel study on the influence of battery state of charge (SOC) and electric generator properties on the dynamic characteristic of a hydro-magneto-electric-regenerative shock absorber (HMERSA) is presented. The focused study is on how the battery SOC and electric generator properties influence the damping force characteristic, the generated electricity and the efficiency of HMERSA. The battery SOC and generator were tested and the relation between current, voltage and electric torque then formulated based on the test result. The empiric formula of the electric variable were used to develop the dyanmic model of HMERSA and quarter model of the vehicle. The results are reported and discussed in this paper.

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Water hyacinth (Eichornia crassipes) is an aquatic plant species that considered as weeds, lead to accelerate eutrophication and sedimentation on the river. Water hyacinth has a potential to be used as a renewable energy source to produce biogas, because it has content of lignocellulose. Lignocellulose need to be pretreated to break down lignin to produce hemicellulose, cellulose and lignin. Chicken manure is added as a source of nutrients and microorganisms to degrade hemicellulose and cellulose to produced biogas. The purposes of this study were to determine the effect of pretreatment and composition of chicken manure and water hyacinth mixed to produce biogas volume. This study was used reactors with a capacity of 6 liters each. Research carried out by a batch process for 30 days. The research variables were the composition of water hyacinth and chicken manure, and pretreatment and without pretreatment of water hyacinth. The ratio of water hyacinth to chicken manure was 90:10; 70:30 and 50:50 (%w/w). The concentration of total solids of the mixture variation in this study was 10%. Pretreatment of water hyacinth was done by soaking NaOH 3% for 5 days at room temperature and then used as raw material. The results showed the highest production of biogas generated by a mixture of water hyacinth and chicken manure 70:30 (%w/w). The cumulative gas volume produced during 30 days was 439 mL. It is a slightly higher than the biogas produced in the same mixture without pretreatment which produced 366 ml biogas. A maximum methane concentration was 20% with pretreatment and 6% without pretreatment.

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In this paper the procedure of the design and the implementation of an electrical equipment to realize geophysical prospecting by means of the method of electrical tomography is exposed. The equipment is of medium power, which guarantees exploration depths quite suitable for commercial and geotechnical applications and studies. The equipment is essentially a DC voltage source of 500 volts which is capable of providing a maximum current intensity of 1 ampere. It also consists of a small current source which counteracts the electric currents that are naturally in the subsoil and which manifest as a potential difference in the surface. A general explanation of the geophysical method in question, allows to understand the basic principles of operation of the equipment and the functions that it has to fulfill. Once the construction of the equipment was completed, a data acquisition was carried out in the field near the municipality of Gachancipa (Cundinamarca). The data obtained with the equipment is processed with specialized software. The images obtained with the software present the distributions of the subsoil resistivities that can be associated to the possible structures and geology of the study area.

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We consider methods for modelling the temperature fields inside a rotary tubular kiln and in the lining of the oven. These models are used for creating a control system that supports the necessary technological parameters and reduces the heat loss through the kiln body to the environment. Two-dimensional modelling of the processes inside the kiln confirms the applicability of a one-dimensional model to these processes. A simulation method for selecting a new design for the thermal-insulation elements, ensuring the reduction of the heat loss to the environment, and performing the required thermal processing is implemented using the ANSYS Fluent software package. A new type of insulation element is proposed, which reduces the heat loss from the kiln to the environment and reduces the temperature of the outer surface of the kiln. A system for monitoring the state of the lining using a thermal imager and a control system that ensures the consistency of the lining without stopping the kiln operation are developed.

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The marine pollution problem in the offshore is becoming more serious due to the expansion of the marine ranching business and the increase in the artificial feed consumption. In order to solve this problem, it is essential to develop eco-friendly culture approaches that can run marine ranching systems without artificial feeds. In this study, we investigated the possibility of growing the fishes without artificial feeds by luring phototactic fishes into the farm using LED (light emitting device) illumination in water. Specifically, we examined the luring capability of underwater LED light for young filefishes to the desired place and analyzed the luring time depending on the wavelength and intensity of underwater LED, night and day, etc. As a result, it was observed that young filefishes responded sensitively to blue LEDs rather than white LEDs and the luring time was independent on the intensity of underwater LEDs in this experimental scale. In addition, while LED light attracted young filefishes into LED area at day time, the filefishes were distant from the underwater LEDs at night time. In conclusion, we expect that underwater LEDs can attract phototactic fishes into the marine ranches and farm, resulting in the fishes to be fed without artificial feeds.

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The performance of a photovoltaic (PV) array is affected by temperature, solar insolation, shading and array configuration. Often, the PV arrays get shadowed, completely or partially, by the passing clouds, neighboring buildings & towers, trees & utility and telephone poles. Partial shading of PV arrays reduces the energy yield of PV systems and the arrays exhibit multiple peaks in the P-V characteristics. The losses due to partial shading are not proportional to the shaded area but depend on the shading pattern, array configuration and the physical location of shaded modules in the array. This paper presents a technique to configure the modules in the array so as to enhance the generated power from the array under partial shading conditions. In this approach, the physical location of the modules in a SP, BL, TCT & HC connected PV array are arranged based on the SuDoKu puzzle pattern so as to distribute the shading effect over the entire array. Further, this arrangement of modules is done without altering the electrical connection of the modules in the array. The SuDoKu arrangement reduces the effect of shading of modules in any row thereby enhancing the generated PV power. Also this paper presents a clear relationship between the interconnections of the PV modules & their power output is proposed through empirical connection laws.

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This paper presents the mathematical model of the propagation of pitting corrosion using a commercial finite element program, COMSOL Multiphysics. In view of the chemical and electrochemical reactions inside a single pit in steel, a two dimensional model that allows the prediction of pit evolution is developed. The model is solved under the Nernst-Planck resolution. The results show that different sites of the geometry give different current densities and different concentrations of ionic species. In addition, the pH inside the corroding pit is also shown to reduce gradually as hydrogen ions gradually accumulate inside the pit, an occurrence expected in pitting behavior.

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In this paper an adaptive threshold techniques has been used which aimed to solve problem of oil spills in oceanic world. As we know oil spill is the biggest issue faced by marine species to overcome this problem an adaptive threshold method is applied for automatic monitoring and detection of oil spills in the ocean. This research is implemented using SAR RADARSAT-2 Narrow single beam data acquired in the Gulf of Mexico SAR image. The study demonstrates occurrence of oil spill in the ocean using image data obtained from the different satellite and detection of dark patches and bands in the images with low time complexity. In conclusion, adaptive threshold can be used as a tool for automatic detection of oil spill and SAR satellite image serves as an excellent sensor for oil spill detection and surveying.

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The use of cold-formed steel (CFS) structures is increasing due to the advances in manufacturing, construction technologies and relevant standards. CFS has many advantages. However the design of CFS structures is complex because of their thin walled open sections making them vulnerable to torsional-flexural buckling and local buckling. Direct strength method (DSM) is the method available for individual beam and column, with certain limitations. To overcome few such limitations this paper attempts to find some simplified formulae as an extension to DSM for stiffened perforated column and two dimensional frames made from same columns. Already experimented column sections and frames were used for validation. Finite Element Method is used to analysis the column and frame for its load carrying capacity with various parameters. Based on FEM analysis simplified formulae are proposed as an extension to use of DSM for stiffened perforated columns and two dimensional frames.

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In this paper some behaviors of domain and domain walls in perovskite ferroics were theoretically investigated. Landau type theory was used to examine the phenomenological properties of domains and domain walls in ferroelectric perovskite materials. Landau predictions on the prototype ferroelectric BaTiO3 showed that it has a stable tetragonal structure at room temperature. The number of domains in the three ferroelectric phases of BaTiO3wasalsocalculated. The results confirmed six, eight and twelve domain states in the tetragonal, rhombohedral and orthorhombic structures of BaTiO3, respectively. The respective spontaneous polarization and domain wall thickness in the stable tetragonal BaTiO3have values of 0.26 Cm-2 and 1.63 nmat room temperature. Analytical and numerical solutions for the relationship between temperature and domain wall thickness and for the spatial distribution of polarizations inside the domain wall are also determined and discussed.

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Bolt joints are commonly used when joining two or more components together in mechanical structures due to its easiness to be assembled and disassembled for maintenance. However, self-loosening is one of the most frequently found as a cause of failure in dynamically loaded bolted connections. This paper discusses a simple way to observe the dynamics characteristic of a fixed-free beam that consists of two beams that connected by a single and double bolt. The tightening torque of the bolt is varied from loosening condition, 2.5 Nm, 5 Nm, 7.5 Nm, and 10 Nm. The dynamics characteristics of the beam are obtained by modal impact testing. The frequency response functions of the beam are observed to analyze the effect of looseness and tightening torque of the bolts to the dynamics characteristic of the beam. It is found that the loosening condition or lower tightening torque will shift the natural frequency of the structure. Significant change will be observed at higher frequency. Moreover, the damping characteristic is also affected by changing the tightening torque. Especially, when loosening condition, the damping ratio becomes much higher than the tightening one. By this condition, the impact testing measurement could be applied as a simple way to monitor or detect the condition of bolted joint in a structure.

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Properties of spreading codes set a limit on the performance of spread-spectrum systems. In this paper, we investigate loading characteristics of even- and odd-degree Gold codes in a multi-user spread-spectrum system, from a few simultaneous users to full system load. Software simulations are carried out on the system performance for transmission of random QPSK symbols through the channel. The performance of up to about a thousand users is considered. Results for six different code lengths, ranging from 31-chip to 1023-chip Gold codes, are reported. The results show that the odd-degree Gold codes give better multiple-access performance than their even-degree counterparts. Whereas the bit-error-rate (BER) of the odd-degree codes exhibited relatively marginal loss in performance when the system was loaded, their even-degree counterparts degraded rapidly in performance, resulting in early emergence of an error floor, culminating in premature system saturation. The results show that the odd-degree Gold codes have better properties that make them more suitable for multiple-access applications.

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Solar energy plays a vital role in distributed generation system for micro grid applications. The interconnection of Photovoltaic (PV) systems with the grid is a difficult task and it requires multiple conditions to be satisfied. One of the major issues in grid connected PV system is islanding; it is a condition where distributed generation system supplies to local loads during grid failure condition. It also creates disturbances in controlling voltage and frequency at the point of common coupling and also degrades the power quality of grid connected PV system. Hence, islanding has to be detected by a suitable anti islanding technique which has faster detection time and smaller non detection zone. Anti islanding techniques are classified into active, passive and hybrid methods. When compared to passive techniques, the active islanding detection techniques have smaller non-detection zone but active methods are not easy to implement and reduces the power system quality. Passive methods are preferred for island detection with reduced non detection zone. This paper compares and analyzes five different passive methods for islanding detection viz. Over and Under Voltage, Current, Frequency (OUVIF) relays Rate of Change of Frequency (ROCOF) relays and Voltage Phase Shift Relays (VPSR) and suggests making them an integral part of islanding detection in the PV system. The proposed passive anti islanding techniques for islanding detection is tested for grid connected distributed generation system by simulation in MATLAB/Simulink platform. The response time of each technique for islanding detection is observed along with non detection zone and the fastest method is identified by comparing the response time of all proposed anti islanding techniques.

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This paper proposes a novel design of power divider based on SIW with extra via. Simulation and measurement are done to investigate the characteristic of the power divider. Characteristic dependence to the power divider structure parameters are investigated, such as: diameter of via, thickness of substrate, and feeding transition. The power divider is designed by using substrate with high constant dielectric (^?r = 6.15). The design obtain minimum structure of 64?95 mm which is reduced the size up to 80% comparing with the previous design. The measurement result is satisfied to requirement parameters target of return loss (S11) less than -14.3 dB, insertion loss (S21 and S31) more than -4.3 dB with at frequency range of 2-3.5 GHz of fractional band width at 54.5%.

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Radioactive waste has to be immobilized prior to storing it in a storage place. The sustainability and safety of an immobilized waste should be ensured. This paper will describe how several tropical materials can be used to achieve that objective. Indonesia has plenty of natural resources, and the ability of its materials to immobilize strontium waste has been studied. The ability of zeolite as an adsorber on cement mortar had been studied. For increasing its compressive strength, coconut (cocosnucifera) and bamboo (bambusavulgaris) fibers had been compared to increase mortar’s strength and durability, as well as rice husk ash as pozzolanic materials in the previous study. The mortars were tested to determine their compressive strength by using Universal Wood Testing after being cured for 28 days. Strontium leaching rate encapsulated on the blocks was analyzed by using Hitachi Zeeman 8000 Atomic Absorption Spectrophotometer for 21 days. This research showed several materials that can be found in Indonesia, such as zeolite, natural fibers, and rice husk, and that are able to be used for immobilizing strontium waste. Cement mortar containing these materials can meet IAEA standards for its compressive strength and strontium leaching rate of cementation, and hence the safety of strontium waste immobilization can be ensured.

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This paper proposes the scope of adaptive Multicarrier (OFDM)-IDMA System in multipath fading channels. MC-IDMA is one of the multiple access techniques operating in multipath fading channels with adaptive sub channel allocation. In this paper we investigate the basic principle of MC-IDMA system, analyzed every model function, and also build a platform for its simulation. It also deals with the transmission of chips over sub channels which are having largest fading amplitudes. Zigzag codes are used as FEC codes. The simulation results shows that the adaptive sub channel allocation scheme used in conventional MC-IDMA system improves the BER performance of the system by large extent.

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In this study, it found that the cycle time of the setup process in a pressing process is inconsistent. This is due to the absence of proper working instruction and workers perform the setup process in varying working steps. Therefore, a new method of the coil setup was developed and standardized which able to improve the efficiency and reduce the lead time of the process. The excessive steps and non-standardize working procedure of the workers in the coil setup needed to be eliminated and some internal steps should change to internal steps to reduce the cycle time. To achieve the objective of this study, the method used in this study is lean tools and techniques such as Time Measurement Sheet (TMS), Standard Work Combination Table (SWCT), Standard Work Chart (SWC) and Single Minutes Exchange Dies technique (SMED). The finding of this study is a new Standard Operating Procedure (SOP) that able to reduce the cycle time and increase the efficiency of the coil setup. This new SOP will be used for the future reference, and it will proliferate to the other similar operation in the department. Future research should conduct in this direction of examining the working mechanism of the workers by using Maynard’s Operation Sequence Technique (MOST) to get more accurate results and achieve continuous improvement.

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Spring suspension is one of the important parts of automobile components that supports and holds the body of an automobile from shaking and vibration. Driving becomes uncomfortable when an automobile traverses high- and low-magnitude roads, such as hills and road roughness, respectively. Therefore, this study aims to investigate the fatigue strain signal characteristic of an automobile spring suspension when driving on different road surfaces and its effect on fatigue damage. In this study, a strain gauge was mounted on the automobile spring suspension system and connected to the data acquisition set to capture the actual fatigue strain signal during normal driving condition. The fatigue strain signal characteristic was analyzed through a statistical method. Then, the fatigue damage of the automobile spring suspension system was determined using commercial finite element software. Results indicate that the characteristic of the automobile spring suspension system is influenced significantly by the type of road surfaces. Thus, this condition contributes to different damages to the automobile spring suspension system.

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These days with the increase in a working a corporate world many people have to sacrifice their time and sleep to survive in the competitive world. This takes a heavy toll on the person’s life cycle and sleep cycle. To make sure that the company is operating profitably and the personal expenses are met the employees are sacrificing their sleep. This difference in the sleep cycle makes them drowsy while commuting to their work place. In case of carpooling or using the government transport people are left unharmed however if they are driving themselves then this drowsiness can put them in a great danger. For e.g. in Situbondo, a worker lost his hand because of drowsiness while working in a wood cutting machine. The system is based on processing the driver’s eyes using ARM 7processor by using a VGA camera that is affixed at the dashboard of the car. We have utilized the canny edge detection process to detect the iris point and find a threshold. In case the observed threshold is met then the brakes of the car are applied and the driver is woken up.

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This study applies TRIZ method on natural fibre metal laminate as car front hood to generate inventive solutions to reduce vehicle’s weight. The increase in greenhouse gasses such as carbon dioxide, methane and ozone in the atmosphere has caused global warming, the implementation of the natural fibre metal laminate as car front hood is expected to enhance the vehicle performance and reduce the gas emission of vehicles which will directly reduce the global warming problem. Fibre metal laminate consists of metal and composite layering which is a lightweight material that takes advantages of metal and fibre reinforced composite. Since there is some limitation in this material, the application of TRIZ method could assist to solve the problem in inventive and effective solutions to utilise natural fibre metal laminate as car front hood. Using the If, Then and But keywords the contradiction of natural fibre metal laminate as car front hood utilization is identified. These keywords will be translated to the appropriate parameter to identify 40 Inventive Principles which lead to TRIZ solution principles and solution idea could be generated. Two contradictions occur throughout this utilization, and the specific solution ideas have been gained, through the application of TRIZ method and the two TRIZ solution principles involved to generate specific solution ideas are #35 parameter changes and #1segmentation.

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With the development of multilayer well drilling technology, this procedure has been applied for the perforating of the producing strata in the wells, making drill holes with ¾ inch thicknesses and with depths of up to 300 feet from the sheath traveling in the formation, as expressed by Radial Drilling serviceinc. Company, performing this drilling technique in the oil wells; in mature fields as in the development of new fields and promises a new horizon of increase of production applying the technology of Coiled tubing. This article shows mathematically the areas that are exposed to flow in the well wall, in vertical wells for conventional perforated and for the radial perforating technique, showing numerically the amount of fluid to be produced using each of the techniques, Also providing a model for the calculation of the possible flow within a radial drilling taking into account petrophysical and geometric parameters which is a contribution to have a starting point when making decisions as to the termination of a producing well or injector.

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Ingredient for the plastic manufacture has a great potential, because in Indonesia, there are varieties of starch crops and one of them is jackfruit. This study was aimed to determine the effect of chitosan and ethylene glycol in the physicochemical properties of bioplastic which was made by utilizing jackfruit seeds. In the manufacture of bioplastic, the ratio of jackfruit seeds: chitosan was 7: 3, 8: 2 and 9: 1 (w/w), while the concentrations of ethylene glycol were varied as 20 mL/ g, 25 mL/ g, 30 mL/ g, 35 mL/ g, and 40 mL/ g (v/w). The product was physically and chemically analyzed by using RVA (Rapid Visco Analyzer), FTIR (Fourier Transform Infra Red), tensile strength measurement, and SEM (scanning electron microscopy). From the RVA analysis of jackfruit seeds starch, the gelatinization temperature was obtained as 88.82 °C with the peak of viscosity of 3276.5 cP. Characterization of FT-IR spectra of the bioplastics with chitosan and ethylene glycol indicated O-H and N-H groups. The best conditions for bioplastics tensile strength was in the ratio of jackfruit seed starch and chitosan (w/w) with 7: 3 and a plasticizer of 0.35 mL/ g at 28.271 MPa. The results of mechanical test was supported by scanning electron microscopy (SEM) analysis that showing bioplastics with chitosan filler and plasticizer ethylene glycol has a smooth and soft surface and also was slightly void.

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Clustering of XML documents is playing a vital role in web mining. The similarity between pairs of XML documents is measured by different distance measures such as Euclidean, Cosine etc. In the XML document clustering, we compute the similarity features by either comparing XML document structures, or XML semantics, or XML content. The XML structures are derived from their x paths. Thus, the process of extracting the XML structures and content is done before clustering for identifying of similar documents. The distinct XML document clusters information is assessed by visualizing clustering method. The aim of this paper is to solve the issue of clustering tendency by a visualized clustering method for the purpose of producing the efficient clustering results. The clustering results of XML documents are evaluated in respect to the performance measures during the experimental study.

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Current cross flow turbines are simple, inexpensive construction and appropriate technology as a rural micro hydro power plant where potentially abundant water potential is available. But the lack of cross flow turbines is of lower efficiency compared to other impulse turbines because it uses only one nozzle. The objective of the research is to improve the performance of multi nozzle cross flow turbine. The research method is to test the characteristic performance of turbine cross flow with multi nozzle through measuring, collecting and analyzing data with the relevant formula. The result of this research is the improvement of performance of multi nozzle cross flow turbine development which reach 83,60% efficiency.

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This work aims design and implementation of a device, which allows blind users to read digital material from the PC through a Braille display electrodes. With this device and after further training, the user will be able to access a huge amount of digital material, achieving higher performance in studies, work, etc., thus achieving greater social inclusion. The prototype accepts plaintext, loaded from a computer, which is transmitted to a Braille display electrode, where the surface of the finger is stimulated electrically with the purpose to simulate the same pressure and embossing of braille paper. This prototype is an initial project, which will serve as a starting point for improving the same and the development of multiple applications.

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In the twin tunnel, the spacing between tunnels or pillar width is an important issue for stability, because the mutual interference between tunnels depends on it during the construction sequence. It must be calculated with respect to tunnel size, soil condition, foundation type, construction method, and construction sequences. The tunnel and soil around it responses are also dependent on the clear distance between tunnels. Therefore, enough clear distance between tunnels must be maintained to ensure the tunnel stability. Sometimes, the surface movements and the interaction with existing foundations are required to be calculated. The shallow and deep twin tunnels in the present research are analyzed using PLAXIS finite element software. The analysis results obtained from finite elements are compared with experimental test results and analytical solutions obtained by other researchers. The present study show that the interaction between twin tunnels can be ignored for tunnel distances greater than the diameter of tunnel multiplied by 4.

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Construction of building structures on very weak or soft soil is considered as unstable and unsafe. Improvement of the soil strength may be tackled by different subgrade improvement methods or techniques; bentonite has been selected as the binding material which was randomly included into the soil at five different percentages of bentonite content, i.e. 3 %, 6 %, 9 %, 12% and 15% by weight of soil. The main task of this work is the improvement of cohesionless soil engineering properties by using bentonite. The selected improved soil properties are shear strength and maximum dry density which are effect the bearing capacity of structure foundations and their stability. After improvement, cohesionless has gain some apparent cohesion by rearrangement of soil particles and decrease the voids between the particles by adding fine particles between them and decrease voids and increase the density, then the required properties can be improved. The soil grain size distribution and the unified soil classification system are used to distinguish the soil sample. The soil is classified or named as (sandy poorly graded) in this work. The experimental program consists of standard Proctor tests, and direct shear tests which were conducted on the cohesionless soil-bentonite mixtures to study their properties. Based on the result obtained, the short coming of this treatment is the increasing in maximum dry density and shear strength with acceptable amount. It is found that the 9 % of bentonite content is the optimum value which gives the better results obtained in this study.

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Due to the urgent need to conserve natural resources, the researchers have been focused on using plant wastes as an alternative source of natural resources. On the other hand, increasing costs of material and rising consumption of natural resources prompted engineers and researchers to look for other materials to enhance asphalt mixture performance, thus minimizing maintenance and rehabilitation of roads as well as saving costs. In this regard, steel slag aggregate is a by product of steel manufacturing, and it is considered as one of the well-known plant wastes, which is suitable for pavements applications. Although it is useful in terms of improving the performances of asphalt mixtures, it has also disadvantages such as expansion volume and high density. However, fibers could be described as a distinct material in the enhancement of asphalt mixture. This study is aimed to evaluate electric arc furnace (EAF) steel slag aggregate replaced natural coarse aggregate in the asphalt mixture reinforced by aramid fiber in order to reduce asphalt layer thickness, and hence reduce transportation costs resulting from high density of the steel slag aggregate. In addition, steel slag aggregate was immersed in the water for 6 months in order to minimize free lime and free magnesia content, which leads to the expansion volume. Six mixtures with different proportion of aramid fiber by total weight of the aggregate were evaluated. Mix1, Mix2, Mix3, Mix4, Mix5 and Mix6 corresponding to 100% of granite aggregate, coarse steel slag aggregate, coarse steel slag and 0.025% aramid fiber, coarse steel slag and 0.05% aramid fiber, coarse steel slag and 0.1% aramid fiber and coarse steel slag aggregate and 0.3 aramid fiber, respectively. However, the fine granite aggregate kept fixed for all mixtures. Thermogravimetric and XRD tests were used to evaluate the benefit of treatment steel slag aggregate while resilient modulus and dynamic creep were the performed tests of the mixtures. Response surface Methodology (RSM) using design expert6 was used to analyze results obtained in order to investigate the interaction between factor and responses of the dynamic creep. Mechanistic empirical pavement design approach was used to examine the possibility of extend service life or reducing thickness of asphalt layer as well as to assess the benefit of ultra-thin asphalt overlay containing steel slag aggregate and aramid fiber in terms of improving service life of existing asphalt layer. The results indicated that method of treatment steel slag was successful in reducing free lime and free magnesia content. Introducing aramid fiber by 0.05% to the total weight of the aggregate into mixture significantly increased resilient modulus and dynamic creep compared to the other mixtures, and it was the optimum content. The results of Mechanistic empirical pavement design indicated that Mix4 have significantly reduced asphalt layer thickness by around 20% if the service life kept constant, or increased service life by 1.24 if the thickness kept constant. In addition, ultra-thin asphalt layer overlay with Mix4 dramatically improved service life of existing asphalt layer.

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Our article contributes by presenting the mathematical foundation for offline programming of industrial robots oriented to the development of flexible manufacturing cells, the simulation of realistic robot that is approached by using the robot kinematics. For the implementation of the offline programming of a real industrial robot integrated in a flexible manufacturing cells, the model of direct kinematics, inverse kinematics and Jacobian is needed to obtain data of the industrial robot in its functions within the flexible manufacturing cells. This model is loaded as an additional module in modeling, simulation using MatLab software and programming software allowing to effectively check its results offline to enrich its content for future contributions.

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Facial expressions are essential to recognize human emotions. This paper focuses on facial expression analysis based on hybrid approach using principal component analysis (PCA) and local binary patterns (LBP). In this paper, the data set contains six various face expressions that include a set of emotional expressions like anger, disgust, fear, happiness, neutral and surprise. It covers five elements like face detection; face part detection; localization of points; feature extraction and classification. The first step is executed by famous Viola-Jones algorithm. Active Shape Model technique is applied for locating feature point in certain area of the face. The feature extraction is performed using PCA and LBP technique. Finally the classification step is performed by multi-class support vector machine (SVM) classifier. PCA technique converts whole facial expression image into global gray scale features as well as reduces the data size. LBP technique is used to extract the texture of the specified region which is in the form of gray scale image. The recognition rate for PCA with multi-class SVM is found to be 67 % and accuracy is 42% whereas the recognition rate of 75% and accuracy of 75% are achieved after the inclusion of LBP. Hence, the proposed hybrid approach gives better recognition rate and accuracy in terms of recognizing facial emotions.

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Nowadays, many high technology machines, mechanical devices, and modern mechanical processes exist to create better products and to produce them instantly. The welding process is one of the mechanical processes to produce a product, and it requires the welder to stay in a static posture for long period of time. Due to this problem, the process is seen to be unsafe and unhealthy to the welder. This study focuses on students who perform welding activities in the welding workshop of an educational institution in Johor Bahru, Malaysia. The aims of this study were to propose a design to improve the welding process and reduce the ergonomics problem. The study used Rapid Upper Limb Assessment (RULA) analysis to analyze the posture of students during the welding process. The RULA analysis and proposed design were performed using CATIA V5R19 software. The results show that the proposed design gave better results which reduced the RULA score from 6 to 2 while the color turned from orange to green (acceptable position).

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In this paper, few numerical methods are proposed to solve transient analysis of electrical circuits namely Euler’s method, Heun’s method and Runge-Kutta method. In order to solve transient analysis, numerical methods for utilization in the companion of analytical method of transient circuit analysis are used to solve second-order differential equations which generated from circuit equations of a RLC circuit. The fourth-order Runge-Kutta method is found out the best numerical technique to solve the transient analysis due to its high accuracy of approximations.

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Training module M2CI is a system that allows both undergraduate students and professionals to acquire control engineering skills and competencies related to the automation of processes. The M2CI has several sensors and actuators for interacting with temperature, position and liquid level plants. Currently the National Open and Distance University has three training modules M2CI located in Bogotá, Bucaramanga and Neiva cities. Engineering students who wish to practice with this system should be addressed to any of these three cities. However, many times the students do not have the means to travel to these cities or do not have time to use these equipment on the schedules in which the UNAD attends the individuals, causing an underutilization of the M2CI.To solve this situation, an application that allows access to the M2CI remotely was implemented. Specifically, access to the temperature plant via the internet is provided, in order to apply classical control techniques such as PID. In this way a virtual learning space was created using LabVIEW to design the user interface that allows remote monitoring and MATLAB to perform signal processing and information processing. In addition, MOODLE was used as a general access tool to the temperature plant and to establish the laboratory schedule. The most relevant scope of the project was the development of an important tool for access to laboratory practices for students of the Electronic Engineering program, fundamental for the training of professionals.

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Unmanned Aerial Vehicles (UAV) has gained interest from the academic community worldwide, especially due to their numerous applications in civil and military applications. The advances in sensor technology, communication and microcontrollers have allowed the research community to develop such applications. The first part of this contribution is focused on the architecture of such a system, while in the second part of the paper the modelling, identification and controller for the yaw movement of the helicopter is presented. The obtained controller was tested in real-life experiments with very good results.

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The presented study discusses the issues of wire-cut electrical discharge machining of small-sized products of complicated configuration made from tungsten. The wide-spread use of tungsten and its alloys is related to the fact that it satisfies the requirements for parts operating under extremely high temperatures. The part "Slot mask" was chosen as an experimental specimen. The technological application of this part is the measurement of the distribution of power along a section of an electron beam, which is used in electron-beam machining of materials. The aim of the presented study is the analysis of the influence of regimes of electrical discharge machining on the process of machining of small-sized products made from tungsten. In order to achieve the set goal, the mathematical and experimental study of electrical discharge machining was carried out. During the mathematical simulation, the spark gap value was taken into account. The experimental study was carried out using the wire-cut electrical discharge machine tool Electronica Eco Cut with various cutting regimes. The brass wire with a diameter of 0.25 mm was chosen as an electrode-tool during the experiment. The working media is distilled water. During the modeling, we considered the nature of the process of electrical discharge machining, which is the transformation of the electric energy of a sparkle charge taking place between the electrode-part and the electrode-tool, into thermal energy, which destroys part of the material. The obtained mathematical model was confirmed by the experimental results. In the study, it was established that the increasing power in the spark gap leads to an increase in the intensity of the removal of material, and, therefore, an increase in the speed of cutting. In the cutting zone there was intense evaporation and melting of metal under the action of non-stationary heat flux coming from heat sources, which have small sizes and small action time and which appear on electrodes under pulse charge. In the study, it was demonstrated that a decrease in the speed of cutting leads to the concentration of large thermal energy on a machined part and an increasing possibility of secondary spark charges, and, thus, increasing cut width. It was established that due to a higher speed it is possible to make thinner cuts. The technological regimes, which allow providing the designated precision parameters during production of the part "Slot mask", were established.

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A theoretical study has been done for the unsteady aligned MHD boundary layer flow as well as magnetic nanofluid’s heat transfer through a vertical flat plate with leading edge accretion. For conventional base fluid, water and kerosene been used as they contain magnetite (Fe3O4) nanoparticles. Magnetic (Fe3O4) and non-magnetic (Al2O3) nanoparticles are compared as well. The governing partial differential equations are reduced into nonlinear ordinary differential equations through a suitable similarity transformation, where the Keller box method is used to solve numerically. Graphical and tabular results are discussed quantitatively in terms of the impact of pertinent parameters like magnetic parameter, magnetic field inclination angle, nanoparticles volume fraction, and thermal buoyancy parameter, ,on the dimensionless velocity, skin friction coefficient, temperature and heat transfer rate. The outcomes indicate that the leading edge accretion can significantly alter the fluid motion and the heat transfer attributes.

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This paper presents a reflector array which is designed at mm band (79GHz) for the applications like, it is easy to achieve gigabit rates with the help of mill metric wave technologies and it includes video transmission from set-top-box (STB) to an HDTV. Here the reflector array is considered as receiving antenna and the transmitting antenna is taken as microstrip patch antenna, the circular patch antenna, patch antenna and patch antenna with a coaxial feed. The simulations were done by using An-soft HFSSv13. The simulated array antenna is designed by using Rogers ultralam 1300 with dielectric constant 3mm.

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The needs of raw water in Medan increases every year in line with the population growth, whereas the quality of hygienic water in the river is insufficient. Therefore, it needs another alternative source to meet the standard quality with low cost. One of the potential sources is Lake Toba. To meet the needs until 2032, North Sumatera Provincial Government intends to use Lake Toba, but it is feared that the decline of normal water level will disrupt the cruise ship, especially when anchored at the port. The Government plans a water supply system in Integrated Water Management (IWRM) to be used collectively to be efficient in construction and operation. This study aims to determine the effect of the use of Lake Toba as a regional water supply and impact on normal water levels. In this paper, the normal water levels were analyzed by inflow and outflow, not based on elevations above sea level. The method of analysis is water balance analysis done in two parts, analysis of water debit requirement (output) and analysis of water supply (input) in hydrological analysis. Comparison of the water balance is a consideration for conclusions. The results showed that the required debit was 82.37 m3/sec. (output discharge) while the supply of rainfall as reliable discharge was 121.79 m3/sec. In addition, the supply of rivers around Lake Toba contributed 87.3 m3/sec, resulting in total discharge to 209.09 m3/sec. It can be illustrated that the output discharge is less than the input discharge, so it can be concluded that Lake Toba can be used as a source of raw water and does not affect the normal water level.

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Previous researches have shown that number of high-speed machine applications in direct drives and generator units increases from year to year. This is due to obvious potential benefits of such power installations: reduced dimensions of high-speed electric machine decreased total weight of installation, increased efficiency of energy conversion. The main purpose of this paper is to select optimal type of electromechanical converter for such installation. Four types of electrical machines were considered: synchronous machine with permanent magnets, asynchronous machine, inductor machine, switch-reluctance machine. Comparative analysis of designed 4 MW 12,000 RPM generators was conducted for active materials weight and specific power value and conclusions were drawn.

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The applications of standard regression analysis on spatial data are not appropriate because of the characteristics of the spatial data. Spatial data has two characteristics are spatial dependence and spatial heterogeneity. Modeling spatial data using standard linear regression model leads to biased, inconsistency and inefficient problems. Several models were developed to accommodate the characteristics of the spatial data. However, the models generally developed to solve only one problem of the spatial data (e.g., spatial dependence or spatial heterogeneity). Four kinds of spatial econometrics models usually used to accommodate spatial dependence are spatial autoregressive (SAR), spatial lagged exogenous variables (SLX), and spatial error model (SEM), and spatial Durbin model (SDM). To accommodate the spatial heterogeneity, geographically weighted regression (GWR) or varying coefficient model (VCM) is usually used. Our research proposed develops a new model to accommodate two problems of the spatial data. The model is developed based on the combination SAR model and GWR model. We call the model as Spatial Autoregressive Geographically Weighted Regression (SAR-GWR). We used Instrumental Variables (IV) approach and Two Stage Least Square (TSLS) to estimate the parameters model. We have done the simulation study by mean Monte Carlo simulation to check the biased and efficiency the parameter estimates. SAR-GWR model provides a better estimate with small bias and RMSE compared than standard GWR. We also found that our method relative robust to the multicollinearity problem. We also applied SAR-GWR model in modeling prevalence rate of Tuberculosis (TB+) and we found the healthy house gives serious effect to the increase of the prevalence rate of TB in Bandung City.

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This study presents the experimental results on performance and emission characteristics of diesel engine with blends of rosemary oil and nano-additive (MgO). These results were run on an unmodified diesel engine. The tests were conducted with total of six blends. B15, B30, B45 are the three blends that have been tested. The other three blends are nothing but the same blends with nano-additive (MgO). The fuel are tested in Kirloskar TV-1 (4-stroke, single cylinder engine) and analysed in AVL smokemeter. Performance characteristics like brake power, thermal efficiencies etc were recorded. Emission levels of CO, CO2, HC, NOx are taken and compared. Efficiency for sample 3 (B15 with additive) was observed to be nearly 35% more than that of diesel at brake power of 2.5kW but after that the diesel curve has a steep slope whereas sample 3 has a gradual rise. Specific fuel consumption for pure diesel is low, then comes sample 3 which has a slightly lower fuel consumption at higher brake power. CO emissions for sample 3 have found to be about 10% lower than that of diesel. HC emissions for sample 4 have a great decrease of 50% when compared to pure diesel. In CO2 emissions sample 2 and in NOX emissions sample 5 had significantly good results.

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The access technology selection, that a user can associate with any radio access technology (RAT) with the availability of multiple RATs available, has been intensively investigated by vehicular Ad hoc Network (VANET). In particular it carries and distributes information, inter-communicates and is capable of communicating with other stationary units deployed along roadways. The current study proposed hybrid optimal radio access selection algorithm (ORAS) for LTE/VANETs network. The periodically broadcasted network information supports mobile users to make their selection decisions; mobiles consider their own individual preferences, cost and partial QoS information signaled by the network while making their decision. The switches algorithm between VANET and LTE based on the load value of network and quality of service requirements were proposed. The simulation results have shown that the proposed algorithm has better performance compared with LTE and VANETs separately in terms of packet delivery ratio, latency and application-level throughput.

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A system that can measure the amount of fuel injected by fuel injectors on a level identical to that of an actual vehicle driving condition was constructed on a laboratory scale without driving a vehicle on a road. In order to inject fuel under conditions identical to those when driving a vehicle, various vehicles’ sensor signals on an identical level to the driving condition were input to the ECU of the device. When the various vehicles’ sensor signals are supplied to the ECU, the ECU drives the injector in a manner equivalent to the vehicle running condition. The vehicle performance parameters under the vehicle driving conditions were computer simulated using GT-Suite®. Vehicle specifications including the engine part load data, a vehicle automatic transmission shift map, the K-factor and torque ratio data of the torque converter, and the transmission gear ratio were used as input data for the GT-Power® simulation. In this study, FTP-75 served as the vehicle driving mode. The vehicle performance parameters simulated by GT-Suite® were the throttle opening angle, intake air flow rate, and the engine speed. Various sensor signals based on the vehicle performance parameters were generated by the FPGA board and real-time OS. When these various sensor signals generated by the FPGA board are supplied to the ECU, the injectors driven by the ECU inject fuel into each collecting chamber. A load cell and a dynamic strain amplifier were used to measure the cumulative amount of fuel injected at 0.05 second intervals after the driving of the injectors started. The cumulative amount of fuel injected while driving the ECU in the Phase I section (0-512 seconds) of the FTP-75 mode was measured and the experiment was repeated 20 times. The average and standard deviation of the cumulative amount of injected fuel were determined at each of the measurement time steps during Phase I. Moreover, an uncertainty analysis of the experimental data was conducted using the t-distribution error function. The cumulative injected fuel quantities measured at 0.05 second intervals were distributed within 2% of the mean value at a 95% confidence level.

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Narrow band interference (NBI) is inevitable in multicarrier communications. The source of NBI may be intentional or non intentional. The performance of the receiver is degraded if the NBI is treated as noise. The bandwidth of the NBI or the number of carriers that are jammed by the interfering sources is very less compared to the total bandwidth of interest of the receiver. Such sparseness enables the application of sparse signal processing principles in the detection and cancellation of the narrow band interference. In this paper, we consider an orthogonal frequency division multiplexed (OFDM) based wireless system and few of its subcarriers are jammed or affected by the narrow band interference. We propose the techniques for cancellation of the NBI interference from the received signal based on compressive sensing (CS) framework and compare its performance with conventional techniques and as well as with the case where the NBI is treated as noise.

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The primary purpose of this paper is to present the space time block code for wireless networks that uses multiple numbers of antennas at both transmitter and receiver. LTE aims to provide enhanced service quality over 3G systems in terms of throughput, spectral efficiency, latency, peak data rate, and the MIMO techniques. Among several operational modes of MIMO, MU-MIMO, the base station transmits multiple streams to multiple users, has received much attention as a way of achieving improvement in performance. Space time wireless technology uses, multiple antennas along with appropriate signaling and receiver techniques offer a powerful tool for improving wireless performance. Space time block coding has been trying to incorporate in the fourth generation of mobile communications, which aims to deliver true multimedia capability. Simulation results have been shown that the STBC which includes the alamouti scheme as well as an orthogonal STBC for 4, 8 transmit antenna case has been simulated and studied. With orthogonal STBC, we have developed an 8 array antenna, which effectively handles large amount of data during transmission.

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