Natural ester insulation (NEI) oil is known as an alternative solution for mineral-based insulation (MI) oil used in power transformer applications. Majority of NEI oil properties are reported to have better performance than MI oil. However, NEI oil still has limited properties especially in oxidation stability, pour point, viscosity and lightning impulse event. Recent studies have shown that the addition of selected mixed antioxidants into NEI oil has improves the oxidation stability properties. However, previous researchers only implemented one-factor-at-a-time (OFAT) method as their experimental design approach and might overlooked any possibility of mixed antioxidants at optimum ratios that will acquire more preferable result. Furthermore, a wide number of test runs are necessary to examine the effect of these antioxidant mixtures on the performance of NEI oil. Therefore, in this study, two-level (2k) factorial design of experiments is used to define the optimum concentration of propyl gallate (PG) and citric acid (CA) antioxidants which will amplify the oxidation stability of the oil. Oxidation induction time (OIT) is used to assess the oxidation stability of NEI oil according to ASTM E1858. The results show that the optimum concentration of PG and CA that yields the highest OIT of NEI oils is0.25 and 0.25 wt.%, respectively. A regression model is also established to estimate the OIT of NEI oil as a function of PG and CA concentrations.

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The current research compares the processing influence of Spark plasma sintering (SPS) over conventional sintering on aluminium alloy AA2219 - MWCNT composites. Also investigations on the effect of MWCNT content on the properties of composite are presented and discussed. Though un reinforced matrix processed under SPS showed 24.68% improvement in hardness over conventional, the same could not be realized in reinforced one due to poor bonding between the matrix and reinforcement. CNT clustering hinders proper densification during sintering and results in poor hardness; hence reinforced samples don’t have a drastic change in hardness with respect to process variation.

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Point of Care Testing (POCT) improves clinical process outcome. It has the potential to reduce errors and the wastage of resources. There is a significant amount of information obtained through the examination of urine. The routine urinalysis consists of two major components: physiochemical determination and microscopic examination of urine sediment. The physiochemical determination includes the appearance, specific gravity and reagent strip measurements. The physiochemical properties of urine may include the following analytes: pH, protein, glucose, ketone, blood, biliburin, urobilinogen, nitrite, leukocytes and specific gravity. Reagent strips provide a simple, rapid means for performing medically significant chemical analysis for urine. Assessment of the dipstick test result is done manually by visually comparing the reactive color of each reagent with dipstick color chart based on the color similarities. The manual interpretation has its weaknesses or failure. It includes the differences in a perception of color, differences in lighting condition and a failure to read several reagents in a specified time. The study of artificial neural networks is motivated by its similarity to work with biological systems successfully. It can learn from training samples or by means of neural network capable to learn. After successful training, a neural network can find reasonable solutions for similar problems of the same class that were not explicitly trained. This in turn results in a high degree of fault tolerance against noisy input data. The study developed a urine analyzer in android environment. It is able to read a 4 parameter and 10 parameter urine strip in real-time. This study also used digital image processing that includes cropping, image segmentation, thresholding, smoothing and recognition. The training is different for each parameter. This is done through Levenberg Marquardt. It performed evaluation through comparison of the standard urinalysis and the device. The prototype is evaluated and certified by a professional registered medical technologist. The accuracy test performed proved to have an accuracy of 96%.

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Presence of crack in a beam increases local flexibility; hence dynamics of the structures gets changed to a considerable degree. Crack gets propagated in the material due to fatigue and at the end, it leads to catastrophic failure, hence it needs much attention. Scientific analysis of such phenomena is important because it can be used for crack detection in structures and fault diagnosis. The natural frequency is most important vibration parameter, as it is extensively used as an input for the crack detection by the vibration methods. In the design of the structures or elements, natural frequency plays an important role. In this study, a theoretical method of analysis of the first natural frequency of an un-cracked cantilever beam in a bending mode is presented. The converged natural frequency formula of a paradigm is extended either to a single cracked beam or multiple cracked beam. To get the natural frequency of a cracked beam by a proposed method, vibration parameter such as stiffness is required; therefore in this study; static analysis of a cracked beam is done by using ANSYS software to get the zero frequency deflection. Stiffness of the cracked beam is then calculated by using conventional formula (Load / deflection). This method gives outstanding results for natural frequencies for both single and multiple cracked specimens. Single sided cracks are considered on the beam, as it is very common localized defect and occurred in the beam due to the fatigue load. Modal analysis is done by using ANSYS software to get the natural frequency of intact beam and cracked cantilever beam. The natural frequency obtained by the proposed method for a crack free beam, and beam having either single crack or multiple cracks gives good agreement with the natural frequency obtained by ANSYS. The main attraction of this method is that it gives one more way to the researchers to determine the modal properties of a cracked beam; the only thing is that some additional tools such as simulation software’s or experimental methods are required to evaluate cracked beam stiffness.

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The main focus in recent power system engineering practices is to get an optimal balance between the cost and emission reduction in thermal power plants. The combined economic emission dispatch (CEED) optimization is performed for allocating the committed units for generation such that fuel cost and emission level are simultaneously optimized while satisfying the generator constraints. CEED problem is formulated by considering both the economy and emission objectives. This bi-objective CEED problem is then converted into a single objective function using a modified price penalty factor approach. In this paper, Water Wave Optimization Algorithm (WWOA) is implemented to solve the CEED problems including the system transmission losses. WWOA is inspired by the shallow water wave theory. The capabilities of the proposed approach are well demonstrated using the numerical results of four test systems. The results are compared to those obtained from other solution techniques like GA, PSO, NSGA-II, FCGA, MABC, MODE, PDE, BSA, GSA and FPA for different cases.

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Two types of reduction in weight can be obtained for a slab. The first is by using lightweight aggregate concrete and the second is obtained through changing the geometry of cross sectional area of slabs for example hollow core slabs and ribbed slab. In this research, two types of reduction in weight can be obtained. The first by using lightweight coarse aggregate (crushed brick) and second is by using hollow core. As a result of reducing the own weight of slabs in the building, the cost of the structure will be reduced. These slab specimens were analyzed numerically by using the finite element computer program ANSYS with dimensions (1.1m) length, (0.6m) width and (120mm) thickness. The specimens are divided into two lightweight aggregate solid slabs with varying shear span to effective depth value, one normal aggregate solid slab with shear span to effective depth equal (2.9), two lightweight aggregate hollow circular core slabs (HCCS) with core diameter (50mm) with varying shear span to effective depth value , one lightweight aggregate hollow square core slabs (HSCS) with core side length (50mm) and shear span to effective depth equal (1.9) and one normal aggregate (hollow circular core slab) with core diameter (50mm) and shear span to effective depth equal (2.9). In this research, the maximum reduction in weight due to aggregate type was (19.28%) and due to cross section (square and circular) cores was (17.365 and 13.64%) respectively. The results of analysis showed good agreement with the experimental test results with variation of (7.56%) in ultimate strength and (7.26%) in deflection. A parametric study have been implemented by using ANSYS program to investigate the effect of number, diameter and area of cores , effect of load Location, effect of adding top steel reinforcement, effect of the distance between applied load and supports and effect of top reinforcement on mode of failure.

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This paper describes the computational ability of artificial bee colony (ABC) algorithm in ascertaining optimal generation scheduling to the hydrothermal power system so as to minimize the fuel cost and emission release subjected to various operational and practical constraints. The hydrothermal scheduling problem is devised as extremely non-convex and bi-objective optimization under practical constraints and linear interpolated price penalty model is developed based on simple analytical geometry equations which blends two non-commensurable objectives perfectly. In order to obtain high-quality solutions within lesser executing time, an appropriate constraint handling mechanism is suitably incorporated in the algorithm that intern produces a stable convergence characteristic. The effectiveness of the proposed method is illustrated on cascaded hydrothermal power system (HTPS) with due consideration of water transport delay between connected reservoirs, prohibited discharge zone of hydro reservoir, ramp rate limit of thermal unit and transmission loss of system load. The desired ABC algorithm reports a new feasible solution for economic, emission and combined economic and emission dispatch in HTPS with practical constraints which is better than the earlier reports in term of solution quality.

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Indonesia has the potential energy of water around 75000-76000 MW. But the utilization is still about 3,783 MW for large-scale and 220 MW for small scale power generation. There are still many people living in rural areas where electricity supply is very low. To answer the social problems in rural areas, it is clearly that looking for alternative energy sources is important to increase people revenue. To solve these problems the exact answer is developing an alternative energy, namely micro hydro. Many theories and research on cross flow has been done up to now aims to enhance the turbine performance by concentrating on the turbine internal flow behavior and preventing the water flow chaotic. Previous research suggests that by putting several guides on the turbine nozzle could increase the water pressure entering the turbine blade. The following study will elaborate on the effect of nozzle angle attack and the water flow rate on the turbine second level toward the turbine performance. By positioning the nozzle direct to the turbine second level it is expected a maximum cross flow turbine second level performance. This study uses a true experimental research. In this case the experimental device is made under a laboratory scale. For this study, the independent variable is the water flow rate and the dependent variable is the turbine efficiency. The turbine rotation angle variation was observed under a nozzle angle attack of 30°, 45°, 60° and 70°. The highest turbine performance was found on a 30 nozzle angle attack, under a 20 Newton loading and on a maximum valve opening. Through this laboratory testing it could be concluded that the nozzle angle attack would greatly affect the cross flow turbine performance.

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CO2 laser cutting is most popular technologies in modern sheet metal processing industries. Thus the technologies have been developed expert system using fuzzy logic model to predict the CO2 laser cutting process parameter on 2.5mm thickness stainless steel sheet. The fuzzy logic model developed in MATLAB using the mamdani techniques. A set of 25 training data used to format of input parameters of laser power, Cutting speed, Gas pressure and focal position and responses are top kerf width, bottom kerf width and kerf deviation. The relationship between fuzzy logic model and experimental value is good correlation. Based on the results the proposed fuzzy model is to predict the top kerf width, bottom kerf width and kerf deviation on stainless steel sheet.

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Recent researches in wireless communications and electronics has imposed the development of low-cost wireless sensor network. Wireless sensor networks are network of sensor nodes with a set of processors and small memory unit embedded in it. Unfailing routing of packets from sensor nodes to its base station is the most significant function for these networks. The conservative routing protocols cannot be applied here due to its battery powered nodes. To provision energy efficiency, nodes are frequently clustered in to non-overlapping clusters. This paper gives a brief overview on clustering process in wireless sensor networks. Hybrid energy efficient distributed clustering methodology for dense wireless sensor networks, the Capacity based Clustering Low Energy Adaptive Clustering Hierarchy (CC-LEACH) has been proposed and the results have been evaluated against the existing Low Energy Adaptive Clustering Hierarchy (LEACH) clustering methodology. Simulation results clearly show an excellent improvement in throughput, packet delivery ratio and number of packets received at the base station. Also, the proposed clustering methodology show a reduction in packet drop, energy consumption and end to end latency for dense wireless sensor networks.

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With the technological development, the research over alternate fuels is increasing day by day in order to help the upcoming generation with a bright and greener future. In order to preserve the existing petroleum resources for future generation, it is necessary to soon switch to any alternate source which is easily available, renewable as well as environment friendly. In this paper I would like to highlight upon the usage of Diesel, Castor Oil and Nano Particles for a compression ignition engine and study the emission characteristics of this fuel at different mixing ratios and analyze the different levels of residue particles.

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The planetary gear hybrid power train (PGHP) is known as one of the most compact speed reduction system. The PGHCVT (Planetary Gear Hybrid Continuous Variable Transmission) introduced in this paper varies continuously the reduction ratio by using an additional external, speed controlled, power source to the traditional thermal engine. The movement of the annular gear in the opposite way to the carrier P (Figure-2). In this way, when the annular is still, the minimum speed ratio is achieved. As the annular speeds up the speed ratio increases up to obtaining a still carrier. Theoretically, reverse ratio is possible by further increasing annular speed. However, speed limits on the annular gearing usually prevent the obtainment of a still carrier or a reverse motion. In any case, even a single stage planetary gearing obtains an extremely large transmission ratio variation. An example of 4WD (four Wheel Drive) vehicle is introduced in this paper with a preliminary design of the gearing system. The efficiency of the transmission is extremely high due to the very limited number of sliding contacts.

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Under the conditions of economic growth, the issue of the rational use of energy resources becomes more and more critical. This article is experimental and is dedicated to the research in the field of the reduction of electricity consumption by the heating elements of the tunnel furnaces of the pipeline type. In the article, it is proposed to replace solid heating components for the impulse ones tunnel kilns on the impulse relay-controlled managing principle. This problem is solved on the basis of the Green's function, presented in the form of a closed management system of temperature control. In addition to the mathematical and physical argumentation of this project, we propose a technical solution - a silicon carbide heating component with impulse sectional heaters (RF patents No. 142770, 132938, 149392, 142848).

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Particulate matters exposure significantly affects human health, especially for those who are working indoor such as in a workplace, house, office, laboratory and vehicle. The objective of this paper is to review the existing physicochemical characteristics of particulate matters from their various sources, to investigate the differences and similarities and the effect of emission sources. Which largely influences the size, the shape and chemical compound. The result shows that the physicochemical characteristics may exacerbate human health.

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This research is focused on choosing and substantiating efficient methods of gas emission control in the working areas in course of intensive mining of gas-bearing coal beds. The methods of predicting methane release in the working area have been analyzed. The reasons why the accuracy of determining the expected methane emission is associated with great difficulties are shown. By the results of field observations, efficiency of methods of control of gas emission management in a working area has been assessed. The influence of working face daily load on methane release into the long wall face has been determined in the conditions of the Kotinskaya mine. Parameters have been substantiated, and control modules of gas emission management in the working areas have been formed. An example of a gas emission control module layout has been shown. A set of recommendations has been developed for intensive and safe preparation and mining of working areas in gas-bearing coal beds. Economic effectiveness of the recommendations and the areas for their rational use have been evaluated. The areas of further research, which are required to improve the efficiency and safety of mining operations in development of contiguous coal beds, have been determined.

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Optimum Design generally becomes rigid or brittle; in a sense that no change or variation in the set value of design variables and parameters is tolerated. A change or variation in set value of design variables and/or design parameters may cause improper functioning or even failure in some critical cases. The Optimum Design is generally so sensitive to change or variability of design variables that it does not tolerate any change or variation though the change is very small and even of the level of geometric tolerances. The main reason behind this is the variation in design variables and parameters get transmitted to the design function causing variation in it. Variation of design function may result in improper functioning or even failure. In this context Robust Optimum Design is that Optimum Design which tolerates variations. The key concept to achieve robustness is to minimize the effect of transmitted variation (often called as ‘Induced Variation’) to such an extent that it is hardly noticeable. If the induced variation is minimized to such an extent then despite variations no improper functioning and no failure is ensured up to a certain extent. Thus the design becomes robust and therefore it is called as a ‘Sensitivity Robust Optimum Design’. In this paper this concept is illustrated with the help of a fictitious problem of designing a conical shaped vessel.

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The analysis of the squeeze films between porous elliptic plates is extended to include the effect of viscosity variation and slip velocity. On the basis of Stokes micro continuum theory of couple stress fluid, a modified Reynolds equation is derived for the fluid velocity and pressure. The pressure distribution and the load carrying capacity of the elliptic plate are studied considering the effects of viscosity variation and slip velocity.

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Vibrations excited by rotating parts determine or limit reliability of machine. Mathematical models of rotor system vibrations are usually do not consider random parameters such as dimensional and weight discrepancy, misbalances magnitudes etc. Although the random factors in particular cases define vibrations characteristics variation and probability of failures related to them. The goal of the work is to develop a technique for reliability characteristics estimation based on mathematical modeling of rotor systems vibrations considering all random parameters mentioned above. The methodology includes three stages. On the first stage an analysis of rotor system failure probability found on fault tree diagram. On the second stage a determinate mathematical model is developed for rotor system vibration characteristics and structural loads evaluation. On the third stage components loads are considered as random values. Using Monte-Carlo simulation factors distribution curves are calculated and fault probability estimation for the rotor system itself is performed. Applicability of the methodology is demonstrated on simple rotor system analysis. System consists of shaft with a disk, mounted in bearing supports. Specifics of parameters dispersion of the system are presented. The developed technique could be used for vibration reliability analysis of mechanical systems like gas turbine engines including complex rotor systems.

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Malino-Manipi main road is a short cut way to connect western and eastern part of South Sulawesi Province Indonesia. This road crosses the Bawakaraeng Moutain in which suffer easily with slope failure particularly in rainy season. To understand the slope condition, it was studied to develop new design for the slope to meet standard of safety factor. A field study have been done to observed actual slope at present condition. The slope consist of volcanic tuff with mechanical properties of unit weight is 20.336 kN/m3; cohesion (c) is 4.089 kN/m2; and internal friction is 34.314o. The slope stability analysis was performed by using finite element method of Phase2-6.0 software. Simulation result showed the estimated of safety factor (SF) in actual slope without considering the groundwater influence is 0.503 and by considering of groundwater level became 0.473. This simulated result shows that factor of safety actual slope indicated the slope in unstable condition. In order to overcome the problem, redesign of slope geometry is needed. A new design of slope was proposed consisting 4 benches with bench height is 8.5 meters, bench width is 6 meters, overall slope is 37O and single slope is 53O. Simulation without considering the groundwater level estimated SF of 1.396 and 1.268 for 500 and 1,500 element respectively, whereas by considering groundwater level resulted SF of 1.343 and 1.250. This simulation was also figure out distribution of mean stress, maximum shear strain, and total displacement.

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Jeneberang River is mined in order to fulfill construction materials demand of Gowa Regency and Makassar City. The aim of this study were to develop the dynamical system for supply-demand model suitable for prospecting the future of construction materials and using the model to explore effects of parameter uncertainty by using sensitivity analysis, and to know how changing in parameters cause change in dynamic behavior of supply and demand. Primary data were collected through field survey and secondary data were obtained from Central Bureau Statistics of Gowa Regency and Makassar City, and Department of Mines and Energy of Gowa Regency. The supply-demand model was built based on multiple regression analysis, validated against field data, and proved well-performed. This study presented a new prediction model of construction materials supply and demand in dynamical system through simulation by using sensitivity analysis. The model is beneficial to learn the behavior of supply-demand interaction and very useful to provide information about future supply and demand sensitivity based on uncertain parameters.

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This paper presents the design of Textile antenna embedded with Z shape Electromagnetic Band Gap (EBG) Structure. The textile antenna is designed using rectangular shape patch with Hexagonal slot. Jeans fabric is being used as substrate. Return loss, Specific Absorption Rate (SAR) value and impedance bandwidth are investigated using HFSS simulator.

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On the basis of justification of the heat and mass transfer processes inside the hothouses during a warm season authors developed methods and means that control dynamics of temperature and humidity parameters and air conditions with the help of complex systems of removal of overheat in hothouses during the all year round and diurnal operations at minimum power inputs.

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The purpose of this study was to determine the effect of treatment alkali (NaOH) on the surface of coconut fiber covering the surface roughness, tensile strength, and the ability of bonding between coconut fiber with polyester matrix. Coconut fiber soaked in a solution of alkali with a concentration of 5%, 10%, 15%, 20%, and then dried in an oven at a temperature of 90 oC for 5 hours. Fiber surface roughness testing is done in two ways namely SEM and surface roughness measuring instrument. Single fiber tensile strength and fiber pull out test was performed with a tensile test. Based on these test results, it was concluded that concentration solution of alkali to give effect to the surface roughness of coconut fiber, increasing the tensile strength, and improve bonding with the fiber and polyester matrix. The alkali treatment increase of the surface roughness of coconut fiber until 3.96 ?m. In the 20% alkali treatment obtained tensile and shear strength is highest, respectively 280,94 N/mm2 and 3,09 N/mm2.

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The modelling of liquid- solid change in castings is extremely important casting simulation studies. In particular the solidification of the molten metals in metal casting methods provides a source of important practical problems. Filling the mold casting process affects significantly the solidification of the melt. Basically solidification is a transient heat transfer problem. For this reason accurate prediction of the temperature field in the castings is to be achieved. Experimental design analysis is often expensive and the geometry and complex boundary conditions encountered preclude any analytical solutions to the problems posed. Thus the motivation of computational modelling techniques has been brought to bear in this area during recent years. This Paper deals with the finite element technique, which has facility in modelling complex domain configurations and handling of non-linear boundary conditions. In this study the finite elements analysis package ANSYS is used to perform the thermal analysis of two-dimensional piston casting model with Al 12% wt. silicon alloy. The latent heat evaluation is incorporated in the heat transfer analysis. The time taken for the completion of solidification, the cooling curves at selective nodes for the combination of casting temperatures 700oC & 800oC and punch & mold temperature of 100oC, 200oC & 400oC are estimated, because it seems to be the appropriate value, for the casting process considered. The results of the simulation study helps in identifying the solidification time, progress of solidification, estimation of various zones (liquid, mushy and solid), change in their configuration during solidification, locating the hotspot, and indicating the source of shrinkage cavity.

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The demand for increased channel capacity in mobile and wireless communication has been rapidly increasing due to multi fold increase in demands of multimedia services and mobile data. In the present scenario, high data rate are offered by WLAN, WiMax and LTE/ LTE-Advanced (LTE-A). Developing a wireless system for more spectral efficiency under varying channel condition is a key challenge to provide high bit rates with limited spectrum. MIMO system with OFDM gives higher gain by using the direct and the reflected signals, thus facilitating the transmission at high data rate. Efficient implementation of MIMO-OFDM communication system is based on IFFT/FFT algorithm. There is several variations in the FFT architecture, which are being used in MIMO-OFDM transceivers and are discussed in this paper. In this work, it is seen that the proposed mixed radix algorithm uses only less number of logic gates, adders and counters. It is been evident that FFT architecture can provide higher throughput rate with minimal hardware cost by adding the features of SDF and MDC pipelined architecture.

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This paper presents the experimental results from modelling and optimization of cutting conditions when turning processes of AISI 316 stainless steel using a central composite design (CCD). Type of AISI 316L, a series of stainless steel, is typical as medical grade that occur difficulties in machining. Power demand and tool life were measured, analyzed and modelled. The results of this experimental work show that the cutting speed has a significant effect on machining responses (power demand and tool life) compared with feed, and that optimum machining parameters was obtained, while following towards sustainability were in terms of minimizing power demand, extending of tool life and improving productivity. The models developed were used for evaluating and optimizing the input process, to obtain optimum machining responses for an overall process improvement.

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Virtual Machine (VM) migration is one of the main features of virtualization. Fault tolerance, load balancing, power management and system maintenance are the great advantages of VM migration. In Live VM Migration, pre-copy approach algorithm is widely used where the memory pages are iteratively copied to the destination host from source host without disconnecting the VM being migrated. But a lot of duplicate memory pages are transferred which takes longer migration time and down time. This paper proposes an algorithm DedupMR, (Deduplication using MapReduce in Live Migration) which performs deduplication of memory pages that are being migrated in parallel using Map and Reduce phases in many iterations of pre-copy approach. In DedupMR memory pages are chunked into fixed size and identification of similar chunks done by calculating fingerprints. Then compressed deduplicated pages transferred to destination VM. The entire process is parallelized by using MapReduce. Due to this deduplication done in short time thus achieves less migration time and down time. MapReduce is a technique that can be customized to process the independent data in parallel. In this paper duplicated pages are reduced by maximum of 29% and minimum of 7%. This can be done in parallel by MapReduce with minimum time.

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Next Generation Networks (NGNs) are primarily propelled by huge potential market for systems of communication and services to suit individuals, which yield ubiquitous and tether-less access to users. Providing seamless handover and ubiquitous services in NGN presents many new research challenges. Priority based call management scheme is necessary to provide low call dropping probability for high priority services by means of channel reservation separately for new call and handoff call. Most of the existing call admission control (CAC) schemes do not consider the vertical handoff from WLAN to Cellular and surprisingly users do not access WLAN even when WLAN facility is available. Proposed call management scheme, which considers all possible vertical handoff scenarios and provides the maximum usage of WLAN. As result, any blocked request in WLAN is taken back by the overlaying Cellular system, if channels are available. So, a request is dropped/blocked only when all the channels of both Cellular and WLAN systems are busy. Main effort is essential to design a Call management scheme for the interworking of Cellular/WLAN, in which service type of the user has been considered. The analytical model has been derived for the call management scheme and validates the same with necessary OPNET simulation results. We provide an extensive numerical result to show that proposed scheme performs better than the existing complementary WLAN (C-WLAN) scheme.

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Stochastic methods are methods that are either directly or indirectly based on the use of unpredictable pseudo-random number generators. In some cases, stochastic methods are the only possible mechanism for the protection of information from an active adversary. We study a new design called “R'-box” which can be used as a construction element of cryptographic primitives of hashing, of block and stream encryption, just like its prototype, the R-box. Based on the use of R-box, we suggest a new way of generating pseudo-random numbers with hidden information, the presence of which does not affect the statistical properties of the output sequence.

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Urban areas are rapidly expanding due to population growth and development, leading to deforestation and land degradation. This study employed remote sensing and GIS techniques to assess urban growth and its impact on deforestation in Bauchi metropolis, Nigeria within the last three decades (1986-2016). The study made use of Land sat images of four epochs; Thematic Mapper (TM) of 1986 and 1996, Enhanced Thematic Mapper of 2006, and Operational Land Imager (OLI) of 2016. Color compositions were made after which the images were geometrically and radio metrically restituted. The images were classified using maximum likelihood algorithm and the accuracy of the classification was assessed by cross-validation using confusion matrices and ground truthing by the use of a hand-held Global Positioning System (GPS). The classified images with their kappa indexes were TM of 1986 (0.83%) and 1996 (0.87%), ETM+ of 2006 (0.90%) and OLI of 2016 (0.92%), respectively. Post-classification comparisons and analyses were performed and the results revealed that changes have taken place in bare surface (+32.43%), built-up area (+565.24%), farm land (+66.42%), forest (-91.80%) and rock outcrop (-49.21%) in the metropolis between 1986 and 2016. The land cover features of the metropolis were reclassified into forest and non-forest for cross-tabulation analysis and the result of the analysis indicates a change-over of 14965.97Ha (39.68%) form forest to non-forest (deforestation) and that of 467.69Ha (1.24%) form non-forest to forest (afforestation) between 1986 and 2016. This shows a rapid increase in built-up area (urban growth) and rapid decrease in forest (deforestation), which may be attributed to lack of improper environmental protection strategy in place in the metropolis. The study demonstrates the potentialities of remote sensing and GIS in assessing urban growth and its impacts on deforestation. The outcome of the study can serve as input into a relationship model for predicting the impact of urban growth on deforestation.

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This project study the thermal expansion of Inconel 718 coating material that formed by atmospheric plasma spraying technique. Since thermal sprayed coatings naturally have a different structure as the solid metal thus the study on the influence of coating structure against the thermal expansion is critical. The main objective of the study is to understand the correlation between coating morphology and different spray parameters with thermal expansion of the coating. Six different samples of dissimilar combination of spray parameters with a range of powder feed rate that differed by various inches of spray distance were examined. In order to obtain a stand-alone coating material for sample analysis, all samples undergoes laboratory works consist of mechanical and chemical process to remove the substrate used for spraying process. The analysis of coating morphology is done by using Scanning Electron Microscope and Optical Measurement Device (IFM). Then, in thermal expansion analysis, samples with 20 gram/minute powder feed rate show minimal dissimilar value than samples with 40 gram/minute powder feed rate. This thermal expansion value is measured using dilatometer machine which is proven to be very useful in the study of material’s thermal expansion values. The results from data analysis show samples of 20 gram/minute powder feed rate have lessen unmelt particles than the samples of 40 gram/minute powder feed rate that leads to not really rough and denser coating material with less percentage of porosity and oxide content. Besides, the unmelt particles also decreased with enlarged spray distance but with growth in percentage of porosity and oxide content. Thus, it can be concluded that both coating morphology and spray parameters influenced the thermal expansion of Inconel 718 coating material.

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Long range marine aids to navigation is not required by current marine navigational practice, therefore luminous range of lighthouses should be reduced. The objective of this study is to determine a minimum luminous range for major lighthouses. The minimum luminous ranges is determined by conducting two steps, namely by modifying the existing geographical range formula and determine a strong linear correlation between light intensity and luminous range with the lowest gradient as possible in a linear graph. The application of minimum luminous range would eliminate the loom of light beyond the lighthouse's geographical range, which is not necessary for current navigational practice. This method is applied to seven major lighthouses in Peninsular Malaysia, which resulted minimum luminous range that ranging from 12.2 nm to 14 nm. The existing luminous ranges of these lighthouses are ranging from 18 nm to 25 nm. These new minimum luminous ranges are sufficient for mariners who primarily rely on GNSS, reduce service provider operational cost and may sustain lighthouses operation in the future.

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This paper presents the development of a University Malaysia Terengganu Plug-in Hybrid Electric Motorcycle (UMT PHEM) driving cycle. The real world speed-time data for UMT PHEM driving cycle is collected using global positioning system. The route is selected based on daily traffic of UMT PHEM. The developed driving cycle consist of 299 s, with a distance of 1.27 km, and an average speed and a maximum speed of 12.68 km/h and 15.46 km/h, respectively. The results obtained from this analysis are within reasonable range and satisfactory.

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Hybrid vehicles are one such alternative and an important part of them is the energy storage system. A series-parallel plug-in hybrid electric recreational boat (PHERB) is a new model for recreation boat innovation was introduced in this work. In PHERB power train, the main power source to drive the boat is electric machine and the primary energy source is an energy storage system (ESS). The ESS was consisted of ultra capacitor and battery. This paper presents modelling of ultra capacitor in MATLAB/SIMULINK environment based on mathematic equation, the design of a closed-loop feedback control system used proportional-integral controller and optimization. The control system is optimized by using genetic algorithm to provide the desired power with respect to the power reference curve. The optimal parameters obtained further improved the performance of PHERB power train control compared to non-optimal one.

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Measurement of gear tooth strength is important procedures in a preliminaries gear design. Two components of spur gear time-varying strength known as tooth surface contact stress (TSCS) and tooth root bending stress (TRBS) can be evaluated using an analytical or finite-element method (FEM). With the advent of computerization era; many researchers turned to finite-element modeling as the important tool in gearing studies. Two different modeling approach commonly used was based on static or dynamics application to the finite-element solution. Both solution are capable to offer several output results and interpretation. However, the complexities of the gear tooth may cause the modeling to imperfect zone of assumption. Therefore, the main aim of this study is to develop a new simple quasi-static modeling based on ANSYS Workbench. The objective was to conduct the analysis of time-varying strength of the spur gear system and compare to the analytical equations. The critical location (CL) for each strength property was also investigated. As the result, the proposed modeling was in a good agreement to the analytical model and reliable to conduct the spur gear time-varying strength analysis.

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Tin tailing sand is the mineral that is left behind after tin extraction. The silica content is high, ranging from 94%-99.5%. Tailing sand for sampling was taken in Batu Gajah, found to contain 95.9 – 98.9 % silica. A high content of silica purity is best for mould making especially for the ferrous metals. Greensand casting is a process of making mould using sand mixed with appropriate amount of clay and water and other additives and is widely used in casting of copper base marine components such as propellers, pumps impellers, pump casings, couplings, valves, and sub-surface platforms. Copper-base alloys such as aluminum bronze, nickel aluminum bronze, silicon bronze and copper nickel are the materials generally used in marine applications due to excellent corrosion resistance. The objectives of this research are to identify the effect of clay contents (addition of 4 wt% and 8wt%) on the mechanical properties of tailing sand and to determine the optimum mechanical properties of tailing sand as a moulding sand for copper based casting. American Foundry Society (AFS) standard of procedures were used as guidelines in conducting the experiments. For mechanical properties, cylindrical test pieces dimensioning of Ø50 mm×50 mm in height from various ratio of clay-sand water were prepared by applying three ramming blows of 6666 g each using Ridsdale-Dietert metric standard rammer. The results were then compared to the typical standard AFS tests for non-ferrous copper based casting. The findings have shown that the tin mine tailing sand with addition of 8 wt% is, applicable for use as moulding sand for making small copper based marine casting mould.

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Resin Infusion is widely used to produce fiber-reinforced materials. In the process, the resin enters a close mold containing the dry fiber performed by pressure difference. This study is about finding the comparison of the tensile strength, compression strength and flexural strength between resin infusion technique and conventional hand laminating for the construction of a 12-feet fishing boat. Both boat were applied with the same composite matrices. All testing was done in accordance to the standard ASTM D3039, D3039M, ASTM D695-02a and ASTM D790-07. The result showed that the resin infusion technique produced better result upon ultimate tensile strength (27% better) but slightly less satisfactory for in compressive stress (12% lower) and flexural stress (34% lower). Even though resin infusion was only better in tensile strength, physically the product is more lightweight with a better resin-to-fiber ratio.

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The aim of this research is to develop a cost effective ultrasonic testing thickness measurement specimens and basic laboratory guidelines for UniKL MIMET. Two specimens has been fabricated with 6 different profiles thickness on the first specimen and 3 different profiles thickness on the other specimen. These profile have been calibrated and tested using Krautkramer USM 35x machine. The thickness and shape of the profile has been determined from the measurement of return ultrasound waves from bottom to the top surface. Then the basic guidelines of the procedure on how to conduct the calibration and testing for thickness measurement has been developed. Finally the “Ultrasonic Testing Laboratory Report” which has been created can be used for the future students in UniKL MIMET to refer as an answer scheme for all 9 different profiles thickness.

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Remotely Operated Underwater Vehicles (ROVs) is dominant to underwater robotics which has very high demand in marine exploration and discovery. This study discussed the up thrust force or buoyancy effects for the fabricated ROV which named as MIMET-ROVTek ROV or known as MIROV. The study is conducted on the stability in terms of centre of mass, centre of gravity, buoyancy and centroid of the MIROV body. In addition, this study also describe the capability of ROV body works at the actual sites in Pulau Tuba, Langkawi up to depth of 15 meters and 2 knots current with a good buoyancy. The material used for ROV ballastis Polyvinyl Chloride (PVC). The centre of gravity, centre of mass, centroid and buoyancy is defined using theoretical mathematical calculation by taking all related physical parameters. Moreover, this MIROV body is modelled from scratch. The final model design were used the commercial computer aided software; SolidWork®. The proven calculated buoyancy were measured to shows the MIROV body achieved the neutral buoyancy once it fully or partially submerged into the water. This ROV also have capability to dive smoothly up to expected depths ~15 meters with associated flotation element and controlled by the vertical thruster assembled to the ROV body.

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The Ocean’s living resources are a treasure for current and future generations of humankind. To sustain the valuable resources, the scientists start to develop unmanned underwater vehicles such as Remotely Operated Vehicle (ROV) and Autonomous Underwater Vehicle (AUV) to seabed mapping and sampling. This underwater vehicle propelled by underwater thrusters (UT), which consists of electric motor and propeller fix at the shaft. However, most of the available UT is not specifically meet the requirement such as the size and the power output. A new UT for an AUV has been designed to suit in. The study focused on new design front cover which is one of most important component in UT and using Aluminum 6061-T6 as material. Finite element analysis on the front cover of the UT reveals that it can withstand the pressure up to 1000 meter operating depth. Another crucial part need to be investigated is the gap between shaft and front cover. It was found that the gap needs to be increased from preliminary design 0.005 mm to 0.008 due to deflection occurred in most critical area is 0.0073 mm. It is important to determine this gap in order to avoid the water leak into the thruster if the gap too big or the shaft contacted the casing if the gap too small.

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This paper is to analyze on many ways and methods in harvesting free energy. Three main components which are wind, turbine concept, gear bearing concept and flux cutting concept have been selected in order to harvest the energy efficiently. The objective of this paper is to find the best possibilities of the integration of the three concepts in harvesting the wind energy. The selected methods and components are based on the geographical area where this project will be implemented. The selection of each components has been decided after short listing each components and comparing it with the same component but with different designs. Based on the comparison, the efficiency of each component that offers more output and result shall be selected and implemented for this research. The results obtain show that the best model that fit the power rating is the Output Error Model (OE). Thus, it will help provide stable supply of electricity to every household in rural areas for daily activities and it can reduce household electrical bill in a long run.

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A voting system consists of rules which must be followed for a vote to be considered valid and counted to yield a final result. The project explained where normal process of election in Marine society, that is Persatuan Nelayan Kebangsaan (PNK) Daerah Manjung Utara, Perak to select their organization for the community. Basically counting ballots need to consider a long time that dragged the results to be published on the next day. Furthermore, process of calculating requires manpower whom could be bias or dishonest person while doing the calculation. In additional, the result could be taking a long time to show up. Thus, it will make the voters keep on waiting to know the result. The Voting System using Android Application is more efficient that the classic method to do an election. The project has develop an interactive GUI panel for voting system. Besides, Apps Inventor 2 had been used to design the entire project. The database that created also does the calculation of the data before transfer the data to the official website. This system has better accuracy compared to the traditional method of counting.

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A fish recognition system is to recognize the type of fish at sea taken using an underwater video camera. It is a computer vision application for automatically differentiating the species of fish. The system developed is to sort the type of fishes in Malaysian seawater. This paper proposed an algorithm of pattern recognition by using Matlab. The fish image recognition system is designed to differentiate the selected features of fish which are the shapes of the fish species. A Graphical User Interface (GUI) is being to represent the recognized fish species based on specific algorithm. The details of the fish are also stated in the GUI for operator information purpose. There are several process to make sure the final image is cleared and the system able to identify the fished detected. The Minimum Sum of Absolute Difference (SAD) method is used to calculate the difference between the chain code and the input fish image. The experiment results using simple technique show an acceptable results. The efficiency of this system is about 72%.

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This paper presents the durability assessment in terms of assessing the reliability analysis under random loading stress using the probabilistic approach of the stochastic process for structural health monitoring. The Markov process proposed in this study has the capability of generating synthetic loading stress data by embedding the actual maximum and minimum loading stresses. This is done by continuously updating the synthetic loading stress in order to generate the stress loading data history for each rotational speed. The purpose of this is to reduce the credible intervals between each data point for reliability analysis through the linear fatigue damage accumulation rule. The accuracy of the Markov process was validated through the finite element analysis and the accuracy and is statistically correlated between the actual and synthetic loading stress. The Markov process showed that the accuracy of the simulated fatigue life has an accuracy of 95% boundary condition when the actual and synthetic loading stress is statistically correlated using finite element analysis. Hence, it was able to provide a highly accurate assessment of durability for the improvement and control of risk factors for overcoming the extensive time and cost required in reliability testing.

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Biodiesel is one the most popular bio-derived fuel among the alternative fuels. The biodegradable, environmental friendly and easy resources are causing biodiesel received extra attentions by industries and researchers in addition to solve the future energy crises. Despite years of improvement, the crucial issue in using bio-derived fuels is the oxidation stability, stoichiometric, chemical composition, antioxidants on the degradation and much oxygen compared to diesel. Thus, the improvement of emissions quality from engines fuelled by biodiesel is immediately required to meet the future stringent emission regulations. Instead of using biodiesel itself, the used of biodiesel blended with additive has been experimented extensively aiming the emissions reductions and improving the engine performance. Therefore, this study was executed to analyze the effects of biodiesel mixed with bio-additives on performance, emissions and combustions characteristics of diesel engine. The division of experimental investigation comprises of 1) performance of diesel engine specifically on brake power, brake mean effective pressure and fuel consumption; 2) exhaust gas emissions focusing on CO2, NOx, HC and CO formations; and 3) combustion characteristics of fuel inside the combustion chamber. Biofuels tested in the study was derived from three different feedstock's i.e. crude palm oil (CPO), jatropha curcas oil (JCO) and waste cooking oil (WCO) at 5, 10, 15 and 20% concentration were blended with selected bio-additive namely Di Methyl Poly Siloxane (DMPS) and D20 palm oil methyl bio-additive formula. Additionally, petroleum diesel namely standard diesel (STD) was examined as well for comparison purpose. A 4-cycle YANMAR TF120ML diesel engine integrated with a 20 HP Eddy-Current dynamometer and mounted with Airrex HG-540 gas analyzers are used. Outcomes of the study implied that blended fuels particularly C10+DMPS and J15+DMPS promotes the optimum performance associated with reduction of exhaust emission specially CO gas. Yet, the best alternative fuels were recommended.

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Welding is the preferred joining method of two or more parts into one piece and it has been developed depending on the combination of temperature and pressure. In Gas Metal Arc Welding (GMAW) process, shielding gas selection has a great influence on the quality and the strength of a welded joint. Shielding gas is very important and therefore any changes in gas mixture or flow parameter affects the arc transfer characteristics and resultant weld quality. Shielding gas systems is rather problematic as mixed cylinders are expensive and gas mixers are often inaccurate, therefore more efficient and alternative shielding gas technology is of interest. The aim of this study is to determine the weld defects by using different gasses which are Carbon Dioxide and Argon. The Visual Inspection, Dye Penetrant Inspection (DPI) and Ultrasonic Testing were used and the data from the inspection were analyzed and measured according to the ISO 5817 and ASTM E164/E165 standard. The findings defined the weld defects of the specimen of the Carbon Dioxide was less than the specimen of the Argon. The findings also identified the Carbon Dioxide shielding gas has a great potential to produce stronger weldment compared to Argon due to the oxidizing potential of CO2 and CO2 has a higher thermal conductivity level than Argon.

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For floating offshore structures or referred to as floaters, the mooring system is vital for station keeping. One of the mooring system used in the FPSO (floating production storage offloading) vessel is the turret system. A turret is a device directly built into the moored vessel for the purpose of weathervaning and attached to the seabed by catenary anchor lines. There are two types of turret used in the construction of FPSO which are the internal and external turret. This analysis involve the designing and performing hydrodynamic analysis for the FPSO based on local environmental criteria. For the research, the analysis involved mooring analysis of the anchor lines tension by using specific engineering software, ANSYS. The result will suggest the ultimate mooring configuration that is suitable for the area of research.

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In order to reduce the global environmental impact from internal combustion engines in terms of emissions particularly in the production of greenhouse gases (GHG), one of the most promising ways is the use of bio-derived fuels. To this purpose, the utilization of biodiesel (pure or in blends) in diesel engines is already quite common in some countries due to its properties comprehensively similar to petro-diesel. The major positive effect not only intrinsic to the significant reduction in CO2 emission but reducing CO, HC and smoke emissions, even though it typically causes an appreciable increase in NOx emissions. However, the use of the biodiesel has some limitation due to efficiency drops and long term complications to the engine. Therefore, this study aims on examine the effects of different biodiesel blends on engine performance and exhaust gas emissions of marine auxiliary diesel engine and recommends bio-fuel that optimizing the engine performance and lower emissions. This study found there has been an increment in engine performance specifically on torque, brake power, brake thermal efficiency (BTE) and brake mean effective pressure (BMEP) along with lower and better in brake specific fuel consumption (BSFC) crude palm biodiesel oil (CPO) and jatropha cursas biodiesel oil (JCO) blended fuels, while decreased in engine performance associated with higher BSFC by waste cooking biodiesel oil (WCO) blends compared to neat petroleum diesel. Aside, the reductions of CO, CO2 and HC by CPO; slightly increment in CO2, NOx and HC by JCO and acceptable CO2, CO and NOx gas productions by WCO has been discovered. Conclusion can be made is biodiesel blend fuels is operable in diesel engines without engine alterations as well as advantageous for exhaust emission reductions yet beneficial to the environmental sustainability.

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