During the past decades, there are several methods or techniques have been proposed to improve the blind source separation (BSS) in signal processing field. One of the methods has been declared as useful technique which is nonnegative matrix factorization (NMF). This paper is presenting a theoretical study on NMF approach which coordinated with 4 divergences which are Least Square Error (LSE) divergence, Kullback-Leibler (KL) divergence, Itakura-saito (IS) divergence and Beta divergence. In which these 4 divergences are normally applied in nonnegative matrix factorization 2 dimensions (NMF2D). Therefore, a novel techniques using machine learning algorithm which is fast, robust and reliable will be discussed in this paper based on most recent BSS technology. Besides that, a discussion and comparison on the different studies of BSS via NMF approach through various applications from different researchers or scholars.

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Recent years has shown that many fast Block Matching Algorithm or BMAs have been proposed and developed that can further reduce the computational cost while maintaining the video signal quality. In this project, a new algorithm called Diamond-Orthogonal Search (DOS) is proposed which employs small diamond search pattern and orthogonal shape in its search steps. Additional step to predetermine static block at initial stage is added to further speed up the search which beneficial to small motion video sequence contents. The proposed algorithm and several established algorithms, namely Full Search (FS), Three-Step Search (TSS) and Hexagon-Diamond Search (HDS) are implemented using MATLAB and their performance are being compared and analyzed in terms of peak signal-to-noise ratio (PSNR), and number of search points. Simulation result shows that motion vectors can be find with fewer number of search points while maintaining close video quality performance with other selected algorithm.

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The study of Nutrition is one of the most important in Science subject but often difficult subjects to teach at the secondary school education level. This paper discusses the design and development of a Personalized Learning Environment for Nutrition (PLENut) by using personalized learning approach to enhance the learning of Nutrition among Form 2 secondary school students. With the technology of multimedia widely used in the classroom, the requirements of multimedia courseware are increasingly high. A courseware is systematically developed using ADDIE model to assist students who had difficulties in mastering and acquiring the concept of the topic. The findings of this study show that the courseware is well designed in terms of using personalized learning elements which goes through a series of systematic testing stages. In turn, it is highly anticipated that the creation of the PLENut, would be a alternative approach so that all students could capture, in a richer and more meaningful manner, the concepts of Nutrition. This process carefully links the organizations needs, instructional strategy and the desired learning outcomes for an effective program. The ADDIE systematic of instructional design focuses on the expectations of the organization, and what learners are to know or do when the instruction is completed.

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This paper will address a new proposed algorithm using wavelet properties to compress an image. It is based on the concept of reducing the near-zero wavelet coefficients at detail subbands (Diagonal, Vertical and Horizontal). This approach is inspired by formerly known Hard Thresholding that eliminate all the coefficient under the fixed threshold value while keeping up the rest. Here, we proposed our own threshold value estimation based on standard deviation concept to find the optimal threshold value at each details subbands. Throughout the experiment done, we found that the proposed algorithm can effectively remove a large amount of unnecessary wavelet coefficient without harming the image quality while increasing the compression ratio and reducing the elapse time.

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Software testing has an important role in software engineering, and is fundamental to Software Quality Assurance (SQA). Besides the popularity of web applications, mobile applications have gained paralleled advancement despite increasing complexity. On one hand, this issue reflects the rising concerns for ensuring performance both of web and mobile applications. On the other hand, a comparative analysis of software testing issues between web and mobile applications has not been completed. Thus, this study aims to employ an effective testing approach that is able to adapt both of web and mobile application testing to detect possible failures. To achieve this, UML activity diagrams were developed from four case studies for web and mobile applications to describe the behavior of those applications. Test cases were then generated by using the MBT technique from the developed UML activity diagrams. Performance measurements Hits per Second, Throughput and Memory Utilization for each case study were evaluated by execution of test cases that were generated by using HP Load Runner 12.02 tool. Finally, the Mean Square Error (MSE) of performance measurements was compared and analyzed among the four case studies. The experimental results showed that the disparity between the mobile applications and web applications was obvious. Based on the comparison analysis for software testing of mobile applications versus web applications that was the web applications were lesser than mobile applications for software testing of four case studies in terms each of the Hits per Second, Throughput and Memory Utilization. Consequently, mobile applications need more attention in the testing process.

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Noise present in the digital mammograms directly influences the capability and competence of a classification task which makes de-noising a challenging problem. In the literature, few wavelets like daubechies db3 and haar have been used for de-noising medical images. Nevertheless, wavelet filters such as sym8, dB3, dB4, haar and Coif1 at certain level of soft and hard threshold functions have not been taken into account for mammogram images. Therefore, in this study two wavelet filters namely: sym8 and daubechies db3 at certain level of soft and hard threshold functions have been considered for classification of mammogram images. Meanwhile, in terms of mammogram images classification using data mining methods review on literature showed that no work has been done using fuzzy soft set based similarity measure for classification of mammogram images. Therefore, the positive reviews produced from past works on fuzzy soft set based classification have resulted in an attempt to use fuzzy soft set for mammogram images classification. Thus, the proposed methodology involved five steps namely MIAS dataset, images de-noising using wavelet hard and soft thresholding, region of interest identification feature extraction and classification. Hundred and twelve images (68 benign images and 51 malignant images) were used for experimental set ups. Experimental results show better classification accuracy in the presence/absence of noise in mammogram images where the highest classification rate occurs with db3 (level 4) with accuracy 62.12 % (soft threshold) with CPU time 0.0026sec and classification rate without noise 63.64%.

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Reverse engineering software is the process of moving back of the Software Development Life Cycle (SDLC) phases by analyzing the software system and then representing it at the higher levels of abstractions. Those processes generate high level information from the implementation phase, which can support the software understanding activities by generating several diagrams and specification documents that describe the implemented software. The UML class diagram represents a valuable source of information even after the delivery of the software. The importance of class diagram comes from its closeness to implementation phase. Class diagram extraction can be done either from software’s source code, or from the executable file. This paper proposed approach for extracting a class diagram from the source code. The proposed approach relies on multi-threading technique in the class diagram extraction which is representing the parallel processing. The motivation behind using multi-threading technique is that, it gives an advantage of faster processing to any software because the threads of the program naturally lend themselves to truly concurrent execution. In this paper, a class diagram extraction using multi-threading technique is designed and implemented using the C# programming language. The implemented approach is tested on three case studies that contain several types of entities and relationships between them. Testing results show that the time needed to extract class diagram using multi-threading technique for the tested three cases is less than the time needed in extracting the same class diagram without using multi-threading technique.

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In this paper, the separation of humic substances from oily wastewater was investigated using Hollow Fiber membranes. Consideration was given to the increase of membrane permeability or flux of the Ultra filtration process. Specifically, several factors which were temperature, pressure, time, pH and surface area of membrane, were studied. The Design of Experiments (DOE) methodology was used to investigate the effect of the factors. From the analysis of variance (ANOVA), it was determined that the pH and temperature of feed solution, time of separation process and trans membrane pressure are significant. The results of this study help to increase the permeability of membranes, thus contributing to a more sustainable filtration system.

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In this paper, the application of the method of lines (MOL) to the FKdV equation is presented. The MOL is a general technique for solving partial differential equations by typically using finite-difference relationships for the spatial derivatives and ordinary differential equations (ODEs) for the time derivative. The MOL approach of the FKdV equation led to a system of ODEs. Solution of the system of ODEs was obtained by applying fourth order Runge Kutta (RK4) method. In order to show the accuracy of the presented method, the numerical solutions obtained were compared with progressive wave solution.

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Artificial Bee Colony (ABC) algorithm is considered as a new algorithm in the swarm intelligence family. This algorithm grabs the attention of the researchers due to its potentials in solving various types of problems. This paper presented the use of the algorithm for the purpose of reconstruction of Arabic fonts. ABC algorithm has been used to find the optimal solution of the curve fitting problem by using the cubic Bézier curve. Since the purpose of this study is to minimize the distance between boundary of the original image and parametric curve, Sum Square Error (SSE) has been used to calculate the error given by these two curves. The procedure of curve fitting process includes the following steps: boundary extraction and corner point detection, chord length parameterization and curve fitting. The finding of this study shows that the proposed method has successfully generated fitted cubic Bézier curve that resemble the boundary of original images and enhance its performance since it produce a small error. Artificial Bee Colony (ABC) algorithm is considered as a new algorithm in the swarm intelligence family. This algorithm grabs the attention of the researchers due to its potentials in solving various types of problems. This paper presented the use of the algorithm for the purpose of reconstruction of Arabic fonts. ABC algorithm has been used to find the optimal solution of the curve fitting problem by using the cubic Bézier curve. Since the purpose of this study is to minimize the distance between boundary of the original image and parametric curve, Sum Square Error (SSE) has been used to calculate the error given by these two curves. The procedure of curve fitting process includes the following steps: boundary extraction and corner point detection, chord length parameterization and curve fitting. The finding of this study shows that the proposed method has successfully generated fitted cubic Bézier curve that resemble the boundary of original images and enhance its performance since it produce a small error.

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We demonstrated the facile and simple route to modify electronic properties of SG (SWCNT) with MB dyes through liquid phase adsorption. The adsorption of MB molecules into the tubes was proved by the notable decrease of X-ray diffraction intensity, depression of the N2 and H2 adsorption uptake at 77 K, and disordered bundle structure of SWCNT obtained from SEM image. The modification of electronic properties of SG (SWCNT) with MB adsorption was remarkably clarified by optical absorption spectra as well as the increase of electrical conductivity owing to the transition in metallic and/or semi conducting nanotubes through the molecular charge transfer interaction between pairs of van Hove singularities. Controlling electronic properties of SWCNT are supposed to be essential for its application in optoelectronic devices.

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Two-level unreplicated factorial design is very common in manufacturing industries. The design can be used to save cost since it usually needs less experimental run. But, problem appears when the experiment is done without any replication. In such kind of experiment, there are problems in identifying significant terms as well as to identify possible outlier in the data. This article discusses about the use of Pareto plot to identify significant terms for unreplicated two-level factorial experiments through numerical example. Meanwhile, the numerical example is also used to clearly describe how to create and interpret both Rank Order Outlier (ROO) and iterative ROO plot in identifying possible outlier in the experimental data.

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The using of vegetable oils with edible and non-edible as diesel blends is prove as an alternative to diesel since they are renewable and has similar properties. Even despite of many years did in improvement, they still issue using this vegetables oil-based fuels which is oxidation, stoichiometric point, bio-fuel composition, antioxidants on the degradation and much oxygen with comparing to diesel gas oil. Thus, the improvement of emissions exhausted from diesel engines with the adding of bio-additive in the blended crude jatropha oil can be replaced as the requirement to meet the less emission regulations in the future. Purpose of this study is to investigate the effects of using bio-additive on combustion process of the exhaust emissions of small diesel engine fuelled by diesel blends derived from crude jatropha oil with different ratio. The engine speed was varied from 1500~2500 rpm, the volume for the bio-additive added are 0.2 ml and 0.4 ml while for the crude jatropha oil blending ratio with diesel is from 5~15vol% (CJO5~CJO15). Decreased of NOx emission and fuel consumption rate found in the combustion process as the increased of volume of bio-additive or booster additive added. The experimental results proved that the used of crude jatropha oil with booster additive in diesel engines was a perfect substitute to diesel.

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The physicochemical characteristics (mass concentration, indoor-outdoor relationship and heavy metals associated with particles) of PM10 and PM2.5 in indoor building which located in industrial area were examined. A walkthrough observation was conducted to identify the sources of the potential contaminants. The concentrations level of particles were collected by using a very fast response hand-held calibrated instrument and the heavy metals which associated with PM10 and PM2.5 were analyzed by using Inductively Coupled Plasma-Mass Spectrometry (ICP-MS). Results suggest that both of PM10 and PM2.5 at point E were permitted to the US Environmental Protection Agency (US EPA). Besides, for the indoor PM2.5, only point B (33.56µg/m3) was not conformed with the standard limit which recommended by WHO (25µg/m3). However, indoor concentrations of PM10 are not conformed with the standard limit value which is set by WHO (50µg/m3). Apart from this, it was found that six heavy metals such as Al, Si, Se, Co, Ba, and Ga which associated with PM10 and PM2.5in the indoor and outdoor environment of the building of chemical industry. In indoor building, most of the concentration of Si are higher than Permissible Exposure Limit - Time Weighted Average (PEL-TWA) which provide the unhealthy indoor air.

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Hybridization of existing competitive modeling methodologies is now an active area of research. The GMDH algorithm is a heuristic and computer oriented method which provides the foundation for the construction of high order regression models of complex system. The research for improving the effectiveness of forecasting models has never been stopped. Currently it was reported that a hybrid system in prediction and classification achieved a higher performance level against the traditional system. The selection of the forecasting model is the important criteria that will influence to the forecasting accuracy. So the enhancement of conventional GMDH model through hybridization will improve the prediction accuracy of the traditional GMDH for time series forecasting. This paper presents a short overview of Group Method of Data Handling (GMDH), its modification and hybridization for time series forecasting. The overview will aim to provide further investigation on the hybrid Group Method of Data Handling (GMDH) with the Wavelet Decomposition for Time Series Forecasting. This modification and hybridization will be proposed a new hybrid GMDH that will be helped for the computational constrain to become more flexible as well as robust/efficient than the conventional GMDH.

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Path Planning is one of the vital aspects in autonomous system. In path planning, safety is important issue that should be taken into account in order to ensure a robot reaches at the target location without collision with surrounding obstacles. Moreover, there are important aspects that need to be addressed in path planning; computational time, optimal path and completeness. One of the popular methods for path planning is Potential field. Potential filed method is capable to overcome unknown scenario, taking into account the realities of the current environment of the robot motion. Two type of forces involved in potential field method; attractive force generated by goals and repulsive force generated by obstacles. However, this method has a major drawback due to local minima problem. This paper reviews the traditional artificial potential field theory that has been modified with variety of algorithms based on potential field method that have been implemented to upgrade the potential function performance in obstacle avoidance and local minima problem.

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Research on polymer nanocomposite has achieved great contribution in many fields. This research is about to determine the electrical insulation strength of the Linear Low Density Poly-Ethylene Nanocomposite/Natural Rubber, LLDPE/NR with different percentages of titanium oxide, TiO2. At the end of this research, the optimum percentage of nanofillers that can enhance the insulation performance can be known. Since the insulation strength has become the main concern on the application of high voltage, the samples of LLDPE/NR are more suitable to be tested using High Voltage Test as being practiced by all of other researchers and scholars. The tests involved in this research is HVAC testing and Lightning Impulse Test. Lightning has being the common causes of fault to the power system in Malaysia. The samples are varied up to 4 percentages of TiO2 nanofillers which are 1%, 3%, 5% and 7%. At the earliest stage, the samples are compressed using hot compressor within specifics time for heating and cooling. The time for both heating and cooling must be precise to make sure the morphological structure of the samples are at the best condition. All samples are designed with thickness of 1.5 millimeters. Then, the samples are tested using both HVAC and Lightning Impulse Test. The samples are tested until they experiencing breakdown. Based on the result of the tests, 7weight % of nanofillers is the optimum percentage of nanofillers that enhance the electrical insulation.

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This paper presents a study on optimization of a complex real-world application; economic environmental dispatch (EED) using two recently proposed modified ABC variants, named as JA-ABC3 and JA-ABC4a. EED is known to be a problem that is difficult yet crucial to be solved. Thus, robust optimization algorithms are needed to solve this kind of problem. JA-ABC3 and JA-ABC4a are recently proposed ABC variants claimed to perform better than the standard ABC as well as other existing variants. Their performances in optimizing EED are compared with the standard ABC algorithm, the existing ABC variants as well as other optimization algorithms. Those observations and evaluations are done in order to identify which variants would give the best optimal solution. The results clearly depict the superior performances of JA-ABC3 and JA-ABC4a in comparison to others in solving 10-generator unit system EED problem.

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This paper presents the design of a dual band dipole antenna with harmonic suppression capability. The proposed antenna consists of a single parasitic element and it operates at frequencies 0.8 GHz, 2.4 GHz, and 4 GHz. The third operating frequency of 4 GHz has been suppressed and this suppression leads to the elimination of noise interference. Thus the final design becomes a dual band (0.8 GHz and 2.4 GHz) dipole antenna which is free from noise interference. The predicted and measured results show that the antenna operates indual-band with a return loss of -30 dB and -21.3 dB at 0.8 GHz and 2.4GHz respectively. This antenna is fabricated on a FR-4 substrate having 4.3 permittivity and a thickness of 1.6 mm. The simulated and the measured results validate the performance of our proposed antenna and a good agreement is found between the results.

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A dual-wavelength erbium-doped fiber (EDF) fiber ring laser in single mode fiber and highly nonlinear fiber is demonstrated and both optical spectrums are compared at 400 mA of Laser Diode (LD) output. The fiber ring laser cavity incorporated sagnac loop had been applied for the laser to lase two wavelengths simultaneously due to high birefringent in polarization-maintaining fiber (PMF). Experimental results show that, owing to the contributions of two degenerate four-wave mixings (FWM) in the HNLF and the dual-wavelength proposed fiber laser is quite stable with small fluctuation power in 1.93 dB within 24 minutes in HNLF.

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The majority of electrical energy consumed in most industrial facilities is used to run electric motors. Therefore it is a persuasive need for researchers to develop advanced electric motors with less cost and high efficiency. There has been a recent interest in flux switching motor (FSM) in which all flux sources are positioned in stator that make the rotor simple, robust and brushless. Development of research has been with toothed rotor structures which exploits changes of paths for the stator teeth but this structure produces less torque and power. Hence, the use of a segmental rotor structure has been developed, which gives significant gains. The primary function of the segments is to provide a defined magnetic path for conveying the flux to adjacent armature coil in stator as rotor rotates. This design gives shorter end-winding than with toothed rotor structure which requires fully-pitched coils. Hence, permanent magnet FSM (PMFSM) and field excitation FSM (FEFSM) with segmental rotor have been developed, but due to their infirmity of less torque generation inherit from less flux linkage, a novel structure of hybrid excitation FSM (HEFSM) is proposed. The proposed design of HEFSM has simple structure with only three Field excitation coils (FECs) and three permanent magnets (PMs) is analysed using commercial 2D FEA package, JMAG-designer ver. 13.0, released by JSOL Corporation. This paper presents the coil test analysis of HEFSM to confirm the working principle besides this cogging torque, back emf and torque vs current densities have been presented.

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In Malaysia, an increasing number of hazardous compounds are being discharged into the mainstream and downgrade the water quality. Textile industry was an example from which pollutants produced and discharged to our mainstream. The main pollution source of textile wastewater comes from the dyeing and finishing process included with the present of high suspended solid (SS), chemical oxygen demand (COD), biochemical oxygen demand (BOD), color, phosphate and other soluble substances. Most of these can be harmful if discharged directly to the mainstream without any precaution. Polluted water can be treated with the use of activated carbon as a media of adsorber. Therefore, this project is aimed to study the effect of using various design shape of commercial granular activated carbon (GAC) for the textile wastewater filtration purposes. Seven types of pollutants contributor will be observed which are total suspended solid (TSS), BOD, COD, color, phosphate, nitrate and sulfate to determine the best design shape. As a result four types of different GAC design show different results of filtration with the best BOD, color, COD, TSS, nitrate and sulfate removal was hollow cylinder granular activated carbon (HCGAC), solid granular activated carbon (SGAC)-I, SGAC-II, SGAC-I, SCGAC-III and SCGAC-I respectively. SCGAC-I design presented to be the best design shape for the filtration. All the design failed to remove phosphate because of GAC source. This finding could help textile industries to determine and consider the novel filtration system in order to ensure textile effluent treated effectively.

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As a snatch theft has become a serious problem to the society, it is required an immediate action to put an end to this problem. One of the solutions is to develop Smart Hand Bag system using Radio Frequency (RF) signal and location tracker as the main component. This project is implemented using an Arduino microcontroller, RF transmitter and receiver module, SIM900 Global System for Mobile Communications (GSM) and Global Positioning System (GPS) module, and 9dB buzzer. This smart handbag produces a loud sound to attract people surrounding whenever a snatch crime happens. The system is also able to track the location of the handbag by using GPS. The location tracked by the GPS module will be sent to the victim by using Short Messaging Service (SMS). Hence, this successfully developed Smart Hand Bag project is expected to help women to prevent this crime from spreading.

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Different statistical packages may produce different results of statistical analysis such as normality test. One of possible sources of the difference is the computational approach. This study tries to explore results of normality tests based on different statistical packages. Empirical data with varied sample sizes were conducted. It was found that SAS, Minitab, and R produced different conclusion in normality test. Meanwhile, sample size also has effect on the test of normality where larger sample size tends to produce different conclusion of normality. But, all the three statistical packages produced similar results of normality test for AD and KS tests.

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Reverberation chamber (RC) is one of the electromagnetic compatibility (EMC) facilities for radiated emission and radiated susceptibility test. The RC is unique because it allows many directions for illumination an object with a higher field strength compared to conventional techniques, for the same input power. The field uniformity and statistical behavior of the field are crucial in a reverberation chamber. Transmit antenna is one of important components in the RC. The proper orientation of transmit antenna orientation contributes to the performance of RC. This paper presents an evaluation of the performance for three different antenna orientations inside a 2.50 m x 2.55 m x 4.00 m reverberation chamber. The evaluation was done in the frequency range from 100 MHz to 1000 MHz. The simulation results show that by implementing proper transmit antenna orientation; the field uniformity inside a reverberation chamber can be improved.

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The purpose of this research was to conduct pharmacological studies of antiparkinson’s activity of Indonesian Mucuna pruriens extract in mice. Effect of ethanolic extract of Mucuna pruriens was studied using in-vivo parameters, i.e. catalepsy and transfer latency. The ethanolic extracts of Mucuna pruriens were assessed at two dose levels (200 and 400 mg/kg) in haloperidol-induced mice. The results showed that Mucuna pruriens extract decreases the cataleptic symptoms and transfer latency score. The Mucuna pruriens extract at a dose level of 200 mg/kg was better than those at a dose level 400 mg/kg in reduce catalepsy and transfer latency scores. Mucuna pruriens extract were considered to be safe up to a dose level of 5000 mg/kg based on the acute toxicology test.

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Low power energy harvesting system is one of the rectenna applications. For this purpose, the compact receiver antenna is needed in order to reduce the power losses. In this paper, A Photonic-Band-Gap (PBG) rectangular microstrip patch antenna is designed for a receiver antenna in rectenna system. It has a compact size with a combination of PBG antenna with Defected Ground Structure (DGS) low pass filter (LPF) in the same substrate. The compact PBG rectangular antenna is built on a low-cost FR-4 substrate with relative permittivity of 4.7 and a thickness of 1.6 mm operating at 2.45 GHz. The antenna is simulated by using CST microwave software and fabricated by using photolithography technique. The prototype has been measured by using vector network analyzer and the results of the proposed antenna are in good performances and steady efficiency.

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The paper describes the homogeneity characterization of a newly developed binder system based on waste polystyrene (PS) and palm kernel oil (PKO) to produce feedstock for metal injection molding (MIM). It is one of a critical step that must be performed in MIM process in order to have a feedstock that is homogeneous and moldable. In this study, water atomised Stainless Steel powder supplied by Epson Atmix Japan was mixed with a new binder system consisting of waste polystyrene and palm kernel oil in a Brabender Plastograph EC rotary mixer. Several tests were performed to assess the homogeneity of the feedstock that was produced at 60 vol.% powder loadings. The 60 vol.% was chosen because the Critical Powder Volume Concentration (CPVC) of the Powder was found to be 64.8 vol.%. The tests conducted were feedstock density, binder burn-out, rheology and SEM morphology observation. From all the tests conducted, it was found that the feedstock shows good homogeneity and suitable for subsequent processing steps in MIM.

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Cerebral palsy (CP) is a disorder which is caused by brain damage. Most of the cerebral palsy children cannot walk on their own. They need an assistive or rehabilitative walking device to help them to walk, however most of these devices are either single- functional and/or expensive. This paper describes the design of a multifunctional and relatively affordable assistive-rehabilitative walker. The design requirements were developed from discussion and interview with CP children and their caregivers. The designed walker has four configuration modes which are standing and walking mode, ground-sitting mode, wheelchair mode and exercise mode. Analysis was conducted to ensure the design is safe to be used, and the the design was fabricated. The fabricated prototype was tested with a cerebral palsy child. Four different tests were conducted with the prototype where the child managed to use the walker for the intended purposes.

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In microwave measurement, for macroscopic material characteristics investigations, one of the dielectric properties which is relative permittivity, ?r is often measured. The main objective of this project is to measure the dielectric properties of sugarcane bagasse and rubber tire dust in the range frequency from 2 to 8 GHz. This dielectric property of this material is essential to modeling the microwave absorber performance. This work include a PNA microwave network Analyzer, samples of sugarcane bagasse, sugarcane bagasse mixed with rubber tire dust, the holder samples, Agilent Technologies 85070E Dielectric Probe Kit, the dielectric constant, loss factor, and also the comparison between these three materials.

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The review was carried out thoroughly on the field of two-sided assembly line balancing problems. Some researchers have highlighted the multi-objective optimization and found this topic is generally very interesting and should be addressed accordingly. Multi-objective optimization is the problems involves than one objective functions. The task are generally in finding one or more optimum solution. In two-sided assembly line balancing problems, usually the two conflicting objectives often used as the main target is to maximize/minimize as follows; i) number of workstation, ii) number of cycle time, iii) work relatedness, iv)work slackness, v) smoothness index, vi) line length, vii) workload balanced. The survey shows that the two evolutionary algorithms that frequently used to solve two-sided assembly line balancing in the past 5 years are Simulated Annealing algorithms and Genetic Algorithms.

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Flyback topology is considered as the lowest part count topology in Switched Mode Power Supplies (SMPS) family with isolated output capability. Without needing any output inductor the critical magnetic part to be considered within the circuit was only flyback transformer. Benefiting the recent advancement of a technology which used in constructing integrated circuits the reproducibility quality of the transformer could be guaranteed. Thus the new flyback topology with split-planar transformer style was introduced. Topology circuit simulation has been conducted and discussed within the model parameters of 5 W capacity, 500 to 1.5 MHz operation, 15 V output voltage with 80% efficiency, taking input from a single photovoltaic module. The most suitable pairs of power transformer to be micro fabricated on a silicon wafer found to be 6 pairs with the core gap of 100 um at 1 MHz operation frequency.

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Active silica from rice husk ash RHA was incorporated in a porcelain composition in substitution of quartz. The influence of the substitution on the bending strength, vitrification behavior and microstructure have been investigated. The treated husk was then subjected to calcinations at 700?C for six (6) hours, after which it was subjected to the XRF analysis. Pellets made with various proportions of kaolin, feldspar, quartz and RHA were pressed at different mould pressures (MP) of 31 MPa - 121 MPa and sintered at a temperature of 1200°C. Bending strength and porosity testing were carried out to the samples. Samples pressed at 91 MPa with 20 wt% of RHA exhibit maximum bending strength.

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Mathematical modeling of glucose-insulin system is significantly important to understand the body regulation control, to analyze experimental data based on clinical trials, to identify and quantify relevant physiological parameters, to design proper clinical trials and to assess diabetes therapies. In general, critically ill patients with blood glucose concentrations between 10.0 to 12.2 mmol/l is identified to develop an acute hyperglycaemia or high blood glucose (BG). Thus, to monitor hyperglycaemia among critically ill patients, this study is focused on observing the glucose-insulin system behaviour based on 40 patients’ clinical data collected in Hospital Tengku Ampuan Afzan, Kuantan, Pahang with clinically validated mathematical glucose-insulin model. By using this model, a critical model-based parameter known as insulin sensitivity (SI) that illustrates patient’s severity were identified hourly for all patients whose on insulin infusion therapy protocol for average four to six days. The results show that a BG normal distribution is attained with median kurtosis of 2.72. While, the 40 patient-specific SI indicate that an outliers-prone distribution occurred as kurtosis 3.96. Thus, abrupt changes in SI is basically due to chaotic interaction between blood glucose and insulin concentrations in bloodstreams. Also, the glucose-insulin behavior pattern among these 40 critically ill patients might be varied due to their main diagnotics illness such as acute kidney failure, cardiovascular disease, etc. Overall, these results might assist clinicians and researchers to understand the glucose-insulin behavior based on patient’s severity illness and helps to inform glycaemic control protocol development in a larger group of critically ill patients.

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Production of electrical power through the use of the gravitational force and flowing water or electricity generated by power derived from the potential energy and running water is called hydroelectricity. The subject study is conducted to identify the potential parameters and desirable design for Archimedes Screw Turbine that potentially generate the highest power efficiency. The study focused on varying two design parameters which are the number of helix turns and the blades of the turbine. Thus, to simulate the best turbine design based on these two parameters, computational fluid dynamics (CFD) methods with constant boundaries condition such as steady state flow condition, isentropic flow and isothermal temperature were applied. The simulation of water streamlines in the screw turbine were obtained to determine the turbine efficiency numerically and theoretically. Overall, decreasing the number of helix turns will enhance the turbine efficiency where results showed that the highest turbine efficiency that can be obtained numerically is 81% with 3 helix turns and 3 blades. However, this study is considered as preliminary parametric study where in the future the number of helix turns and blades should be varied in a larger range to elicit the trend in terms of turbine efficiency. Potentially, varying the other design parameters such as length and slope of the screw runner blade should also be considered to obtain the highest turbine efficiency. Also, further investigation is needed as the turbine is assumed to be in steady state condition instead of in rotating motion as it is more practical and realistic.

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Silicon on insulator (SOI) technology refers to the use of a layered silicon-insulator-silicon substrate in place of conventional silicon substrate or known as a Buried oxide layer (BOX). SOI Metal Oxide Semiconductor Field Effect Transistor (MOSFET) has been introduced to enhance the drive current (ION) and low short channel effect (SCE). The virtual device fabrication and characterization were executed by using ATHENA and ATLAS modules from SILVACO TCAD tool. In this paper, an orthogonal array of L9 in Taguchi method was used to analyze the consequence of Source/Drain factor toward ION in SOI Metal Oxide Semiconductor Field Effect Transistor (MOSFET) device. Four process parameter (control factor) has been chosen to perform nine experiments considering the interaction effect towards 10nm SOI MOSFET, whereas two noise factor were varied for 2 levels to get four reading of ION for every row of the experiment. The signal-to-noise (S/N) ratio of a ION for an SOI MOSFET device is 56.40 dB and within the predicted range. As conclusion, it is shown that L9 orthogonal array in Taguchi method is effectively can predict the best solution to finding the best setting level to produce the highest ION. Based on analysis of variance, S/D Implant energy is one of the significant factors that effecting ION in SOI MOSFET.

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In this paper, we introduce a new compact dual-polarized conformal slot antenna fed by two orthogonal Coplanar Waveguide (CPW) semi-discs. To achieve a high isolation between the two ports, a strip is inserted diagonally in the ground plane. The simulations are done using the Computer Simulation Technology (CST) Microwave Studio software. The simulated results show that the proposed antenna provides an impedance bandwidth enough to cover the Ultra wideband spectrum, and exhibits a good isolation across the operating band. These features make the proposed concept very attractive for conformal ultra-wideband (UWB) antenna applications which used polarization- diversity technique.

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This study provides solutions to aLR-fuzzy linear system (LR-FLS) with trapezoidal fuzzy number using matrix theory. The components of the LR-FLS are represented in block matrices and vectors to produce an equivalent linear system. Then, the solution can be obtained using any classical linear system, such as an inversion matrix. In this method, fuzzy operations are not required and the solution obtained is either fuzzy or non-fuzzy exact solution. Finally, several examples are given to illustrate the ability of the proposed method.

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Nowadays, fiber reinforced plastic composites are replacing metals which are being used for many years. This is due to the fact that fiber reinforced plastics have high strength to weigh ratio, low cost compared to metals, and high resistance to corrosion. This paper aims to simulate the effect flow induced fibers orientation on the tensile properties of short glass fiber reinforced nylon composites. Dog-bone shaped tensile testing shapes were simulated using commercial software called ANSYS. For the simulation, the concentration of the glass fiber was varied as 10%, %, 20%, and 30% by weight. First, the orientation state of the fibers during molding were determined experimentally and it was observed that majority of the fibers were aligned to the flow directin near to the top and bottom mold walls whereas they aligned perpendicular to the fow direction in the core region. Structured mesh was constructed with 2623 elements and 2804 nodes. As in input for the simulation, elastic modulus for each composite was obtained by performing tensile test experiment. The simulation results indicated that the yield stress values increased significantly from 13.21 MPa for pure nylon to 56.65 MPa for 30% by weight glass fiber which leads to a conclusion that the higher the percentage of the glass fiber reinforcement, the higher the tensile strength of the composite would be. Moreover, the numerical results showed a decreasment in deflection with the increments of fiber content. Hence, this study could assist in decisions regarding the design of reinforced composite products.

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A study of natural radioactivity in samples of groundwater and soil were collected from nine districts in Johor and it was carried out on years 2008 until years 2010. The totals of seventy locations were selected as sampling point by referred to the reconnaissance maps and have been considered to the certain factor such as groundwater sources, soil types and the surrounding activities such as industrial or agricultures. At sampling point, the portable gamma-ray survey meter, Model 19 Micro R meter manufactured by Ludlum is used to measure the gamma dose rate at the surrounding areas. In the laboratory, the sample preparation process is made according to the recommended steps and the preparation process of groundwater and soil are different from each other. The technology of HPGe spectrometer is used to counting all samples within 3 hours detection time and the collections of data on radionuclide is in the form of gamma spectrum. Further analysis is depends on the measurement of the natural radioactivity of the elements 238U, 232Th and 40K in order to get the estimation results of the concentration radionuclide contained in groundwater and soil samples. At last, the graphs were plotted for the relationship between the concentration of radionuclide in the samples and gamma dose. At last, graphs were plotted for the relationship between the concentration of radionuclide in the samples and gamma dose.

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This paper describes an optical fibre sensor system for displaying of ammonia gas spectrum. An open path optical technique is used to analyze the absorption lines of ammonia within the Ultra Violet Region. Experimental results describing the operation of the sensor with varying gas concentrations are presented and are compared with recorded results calculated from measured experimental flow rates. The results show the sensor is capable of detecting small concentration changes of ammonia.

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Basically it is known that humankind is reliant on plants for some purposes like getting food, shelter, and oxygen. Humans and plants are absolutely inseparable. Moreover, most of modern buildings right now are using closed ventilation system to energy conserve, which cause rate of oxygen are decrease. Worse yet, indoor air contaminants are accumulating if insufficient of fresh air happen at interior spaces. Therefore, introduce indoor plants is seen as alternative solution to deal with this problem, and their ability is gaining attention. There are many researchers attempt to prove the truth of indoor plants to be able freshen the air, as well as to act as air filtration. However, lighting on indoor plants should be consider, because light is important to plants live. With a lack of light intensity is applied to the plant, it will cause such a damaged plant. Preliminary study was conducted, and the aims of this study are to determine the abilities of seven type s indoor plants (Anthurium, Syngonium, Dumb Cane, Kadaka Fern, Golden Pothos, Prayer Plant, and Spider Plant) to reduce carbon dioxide (CO2). Indoor plants selected have been tested individually in one cubic meter of glass chamber, during day time. The results showed that the Dumb Cane is the best indoor plant, compared to seven others indoor plants to absorb CO2 with the absorption rate are23.9%. Meanwhile, Prayer Plant is the lowest rate for absorbing CO2, with rate of absorption is 17%. However, all indoor plant that are tested are capable to absorb CO2, it is because nature of plants issue CO2 during the photosynthesis process to produce oxygen and growing purpose.

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The problem on influence of slip velocity on convective boundary layer flow of Jeffery fluid with convective boundary conditions together with the effects of magneto hydrodynamic is investigated. The governing equations correspond to the discussed problem are first transformed into ordinary differential equations using similarity transformations before the computation process is done by Keller box method. It is found that, the magnetic parameter enhanced the fluid temperature and lowers the velocity of the fluid flow while the growth of the values of Prandtl and Deborah number weaken the distribution of the fluid temperature.

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Unlike Direct Current (DC) motors, the DC servomotor angular position can be controlled at a specific angle by using a control signal. Arduino has recently been used in a wide range of control approach, especially involving closed-loop system with servomotor due to its flexibility and simplicity. In order to control the DC servo motor, there are three different methods that can be used by using Arduino namely Arduino Integrated Drive Electronics (IDE), Support target for Simulink (Support Package) and Arduino Input/Output (IO) Package. This paper presents a comparative study on the servo motor position control (with voltage feedback) by using the above methods to find out the best technique to control the complex servo motor system with closed-loop position feedback.

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This paper presents the development of an Intelligent Mini Robot Fingers by using the Shape Memory Alloy (SMA). Taking into consideration the advantages of the SMA, a prototype of mini robot fingers is developed which will be actuated by the SMA. The mini robot fingers has 4 fingers with 3 degrees of freedom (DOF) in each finger. Hence, 12 DOFs of robot fingers are developed to allow a greater flexibility. The SMA is an actuator that permits the elimination of motor to control the movement of the robot fingers. In this study, thin SMA is selected due to low resistance, low current requirement and able cooling within a short period. The function of SMA in each finger is similar to the muscle-tendons structure of the human hand. Robot finger flexion is performed by contraction force of SMA using the characteristic of electrical resistance of SMA. The mini robot fingers have articulated fingers with cable tie (as spring) mounted on the backside of each finger. These cable ties provide the necessary, restoring force for SMA contraction as well as open the fingers for relaxation. From experiments, the grip force is 0.2 N, and can support the object up to 20 grams.

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Gender-neutral design is regarded as a kind of fashion symbol, it also creates the new opportunity for product successful. To help the company to build the product image of gender-neutral effectively, the cognition and preference of consumer on gender-neutral design were discussed using scooter design as an example. Kansei engineering was applied to extract the factors generic of gender-neutral emotions, and to analyze the relationship between design attributes and users preference of gender-neutral style on scooters. The result is used to enable product designers to obtain the optimal design alternatives that best meet consumers preferences.

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Optimal tag coverage is the most crucial aspect for deploying RFID (Radio Frequency Identification) system in a large scale. From the literature, optimal tag coverage can be considered as a high dimensional optimization problem and often solved using nature-inspired algorithms. In this paper, PSO (Particle Swarm Optimization) algorithm is used to optimize the tag coverage problem. This paper also investigates the effect of varying two parameters of PSO (swarm size and iteration number) to the performance of the algorithm. During the simulation sessions, both parameters are set at 50, 100, 150 and 200. Next, sets of comparison were made. From the experiment, the best set of results is generated when the swarm size is set at 200 and the iteration number is at 50. This is very encouraging because for the iteration number at 50, the runtime is much less (4.9s) compared to the higher iteration numbers (100, 150 and 200). The percentages for additional runtimes for iteration number set at 100, 150 and 200 are 103%, 204% and 341% respectively.

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This work is concerned with the design and development of draw forming test device with double action draw forming mechanism. This device is designed to operate on universal testing machine (UTM). The dual phase auto-steel about 1.2 mm thick is used as deformable blank. The double action mechanism is generated by an external hydraulic system to equally apply the blank holder force (BHF). Hence, the punch force is driven by UTM s hydraulic system. The design load and die displacement is initially predicted by FE simulation at maximum load of 123kN and 14 mm displacement respectively. Draw forming result shows the fracture is recorded at 108 kN of punch force and 9.5 mm of displacement depth.

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This paper implements the Shape Changer code with MATLAB to approximate a set of planar profiles that have significant differences in arc length. The first step is to specify the types of segments; the mean segments (M segments) or/and the constant curvature segments (C segments). Then, a chain of rigid body segments from a set of points is created. Additionally, compound segments combine the M and C segments where possible. This work is extended to prepare the parametric data of the segments and profiles to be transferred into the Catia CAE software via macros commands. Next, Geometric Constraint Programming (GCP) techniques are applied to synthesize a mechanism.

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This paper is an introduction to our research which aims to develop a driver safety assistant system using an in vehicle video camera. It is a real-time recognition system which uses vision sensors to detect passengers and driver fatigue conditions. The system assesses the ability of conducting safe driving and notifies the driver for any dangerous situation. Moreover, safety actions are to be performed by an embedded vehicle controlling system. This review paper is to assess the current status of research.

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The purpose of this research is to investigate the corrosion behavior of ductile iron (DI) and ductile iron added with different percentage of cobalt alloying element. All the samples were produced by casting technique which is ductile iron (DI), 0.5%Co DI, 1%Co DI, 2% Co DI. All the composition of these samples was determine by using spectrometer machine. For corrosion behavior, two different testing techniques were used which is polarization test and weight loss measurement. Testing was done under 3.5% NaCl in room temperature. All specimens with alloyed addition on DI give a better result in corrosion rate. This research will give better understanding and exposure about the corrosive behavior of DI, thus, improvement can be made for prevention of corrosion.

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This paper concerns about the implementation of two wheel self-balancing vehicle using Arduino. Tilt angle and motor speed rate are functioning as input of the system to perform balancing of the vehicle. Inertia Measurement Unit (I.M.U.) and DC motors were used as sensor and actuator respectively for this system. Moreover, the control of vehicle system used PID controller and implemented in Arduino board. This project is represents and focuses on power drive system because it involves a series of power drive and embedded controllers. The hardware of the vehicle is being produced and tested in laboratory.

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This present study discussed the usage of LPG in spark ignition engine. A brief review on the LPG conversion technology and the fuel system has been studied. The main concerned in using LPG as fuel is lower volumetric efficiency compared to gasoline that gives lower power output also been discussed.

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This document contains the formatting information for the papers presented at the International conference on Engineering Technology International Conference . The conference held at (Bali, Indonesia) during August 10-11, 2015. The microstructure and mechanical properties of the material to be welded mainly depends on the temperature during welding. The difficulty in measuring these temperatures during friction stir welding, pose a serious concern to researchers, practicing engineers and technicians. Hence, there is a necessity for searching alternate solutions. In the present research, a simulation model has been developed by using hyper works software to estimate the temperatures and flow stress. The modeling of Friction Stir Welded AA6061 alloy has been carried out by three dimensional nonlinear FEA model, the temperatures are evaluated. During the welding process the peak temperatures and flow stresses are presented around the rotating tool pin, and plates are found to be 6150 C and 4500 C.

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Embedding of internal micro channel into a standard cutting tool alters the thermal and mechanical behaviors of the tool in a machining process which consequently improves the machining performance in terms of wear mechanisms of the tool and surface roughness of the finished product. Obviously conditions of the fluid such as type, temperature, viscosities and speed need to be modeled accurately to determine their effects on the micro fluidics performance although the development of ideal mathematical equations to precisely pose a machining process is almost impossible due to the geometrical, physical, thermal and chemical complexities of the process. This work aims at computational fluid dynamics modeling of the internal flow inside the micro channel of 0.8 5m diameter to quantify the flow regimes along the cooling manifold for improving the performance of a cutting tool. Two procedures have been performed in this work, namely (1) the determination of flow regimes in the internal micro channel and (2) the mapping of the flow speed topography of the cooling fluid. The fluid in this analysis is assumed to be Newtonian incompressible fluid since it will not change phase while exchanging the heat. The results show that the Reynolds Number in the micro channel manifold are distributed in the range of 528 and 6604 which the numbers higher than 2320 are considered turbulent flow. On the other hand, the empirical correlations show that with the inlet flow rate of 0.3 l/min, the fluid speed at the micro channel part that is closest to heated region can reach up to 7.706 m/min. The outcomes of this work determine the pump capacity of the system and the values obtained from the numerical analysis can be used in the thermodynamics analysis of the cooling performance of the micro channel in removing the heat generated during machining.

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Magnesium alloys (AZ91D) have excellent physical and mechanical properties. Unfortunately, MgAZ91D has a number of undesirable properties including poor wear and corrosion resistance that has obstructed its use in many applications. Therefore, it is necessary to improve the wear and corrosion performance of MgAZ91D for their future applications. Over the years, various methods of surface treatments for MgAZ91D have been studied and most frequently used are electrochemical plating technique, conversion coating, ion beam and etc. For each of the surface treatments discussed, several types of corrosion behavior and wear property have been studied with the conclusion is compared to each other.

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In this paper material characterization and free vibration analysis of polyester resin based two, four and six layers chopped strand mat (CSM 450g/m2 specific weight) glass fiber reinforced with (CGRP) composite materials has been determined. In material characterization the tensile, flexural, impact, inter-laminar shear strength, fracture toughness has been evaluated. The results have revealed that, the four layer CGRP composite material has high impact, inter laminar shear strength and fracture toughness compared to two and six layers composite material. Free vibration analysis was carried out to determine the natural frequency of the CGRP composite materials theoretically and numerically (FEA). The result obtained from free vibration analysis indicated that natural frequency of six layers CGRP composite material is more than two and four layers CGRP composite material.

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Numerical simulation on the rib turbulated flow inside a convergent and divergent rectangular channel with square ribs of different rib heights and at different Reynolds numbers (Re = 20,000, 40,000 and 60,000). The ribs were arranged in a staggered fashion between the upper and lower surfaces of the channel walls. Computational investigations are carried out using computational fluid dynamic software ANSYS Fluent 14.0. Suitable solver settings like turbulence models were identified from the literature and the boundary conditions for the simulations on a solution of independent grid. Computations were carried out for both convergent and divergent channels with 0 (smooth duct), 1.5, 3, 6, 9 and 12 mm rib heights, to identify the ribbed channel with optimal performance, assessed using a thermo hydraulic performance (THP) parameter. The convergent and divergent rectangular channels show higher Nu values than the standard correlation values.

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The study undertaken in this article is to develop a reliable and comprehensive numerical modeling of particle transport in pulmonary flow based on the use of CFD-ACE code of commercial calculation. This code includes a fluid solver that solves the Navier-Stokes in a finite volume formulation. The CFD-GEOM software was used to create the 3D surfaces of the generic model geometry Weibel and thereby generate the tetrahedral mesh unstructured finite volume. The air flow is assumed laminar stationary (or unsteady only in bronchial models) and incompressible, the particles of diameter 5 micrometers are spherical and non-interacting. So we have successfully modeled the flows and the transport of particles in simple configurations (Model Weibel) and realistic configuration (rat lung) and what we can say is that the simulation , although expensive in terms of computer memory and time (specially for particle deposition), does not present insurmountable difficulties. As against obtaining a realistic geometry and the associated mesh generation remains a delicate stage.

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The wire rope isolator (WRI) can effectively provide vibration isolation of equipment and structures. The main advantage of WRI is the effective isolation in all three planes and in all directions. The WRI provides the damping of the external disturbance through its friction between the wire strands. The present work is the study on the performance of WRI in the isolation of equipment supported on structures. This study is performed in four different cases namely, Fixed Structure and Fixed Equipment, Isolated Structure and Fixed Equipment, Fixed Structure and Isolated Equipment, Isolated Structure and Isolated Equipment. The present work compares the performance of WRI in all the four cases. The study also extended on the parametric study for the effects of frequency of external excitation, weight of the equipment and excitation direction. It is found that the WRI were effective in providing the isolation for the frequency studied and increased weight of the equipment enhances the performance of WRI. The present study can be used to identify the different ways to provide the isolation of the equipment supported on the structures through WRI.

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Flight data recorder (FDR) is an electronic device installed in the aircrafts for the purpose of investigation of the accidents. FDR is an assembly of both mechanical and electronic components. It is necessary to design the FDR with high strength and stiffness for both static and dynamic loads to avoid the failure when accidents or crash of the flights occur. Typically the parts of the FDR will manufactured by both metals and non-metals. The parts of the FDR are experienced by different types of loads like harmonic, random, and shock vibration loads. High deformations and stresses will be developed during these loads and internal collisions of parts can take place and then leads to individual part or assembly failure. So it is very important to analyze the response of the FDR subjected to these loads. In the present work, FDR is analyzed under random vibration loads in the form of base acceleration in X, Y and Z directions by using finite element simulation software Ansys Workbench. The parts and assembly are modeled in Ansys workbench. The response of the structure is analyzed for with and without rib FDR cases. Later the best case is analyzed with composite materials. Carbon epoxy and E-glass epoxy 3-D composite materials are chosen to perform the analysis. Proper boundary conditions, mesh and contacts between parts are assigned to the FDR assembly. It is observed that FDR shown better stiffness with ribs for all directional random vibration loads than without ribs. The deformations in FDR with ribs and without ribs are found to be within the limits of clearance available. Hence there is no risk of collision between the parts. It is observed that there is 28.26% of weight reduction in carbon epoxy composite FDR compared to the typical FDR with ribs.

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Contact between two objects is an important facet in multibody dynamics. It is a discontinuous, non-linear phenomenon and consequently it requires iterative simulations. The paper presents the reliability evaluation of the retraction landing gear mechanism by three contact models Viz. Impact Function Model, Coefficient of Restitution Model and Clearance Link Model. The simulations have been performed using the standard commercial multibody dynamics software ADAMS. The precision of these simulations depends on user-defined parameters like stiffness, Damping, Penetration Depth, Force exponent, Penalty and Restitution Coefficient that impacts the overall reliability of the mechanism. The optimal value of these parameters have been obtained by an optimization process using Design of Experiments tool available in ADAMS to match with the nominal values without any clearance.. The overall reliability of the mechanism has been evaluated at different instants of the retraction cycle by using Response Surface Based Monte Carlo Simulation and Direct Monte Carlo Simulation by using in house codes created in MATLAB software. The comparison, significance and accuracy of the results obtained using the above -mentioned approaches has been discussed and the impact based contact modeling for the clearance appears to be accurate and realistic for practical applications.

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Data mining technology has become a boon for all the engineering fields in today s world. With the great outburst of data comes a greater responsibility (i.e., organizing and managing the data). Large amount of data is fragmented into smaller chunks of data and ran over hundreds or thousands of servers in parallel ways to extract useful data in big data analytics. With the boom in technology and the huge growth in the data, clustering has become a crucial part in identifying the similarities based on many parameters in a given data set that influences in decision making. To reinforce this clustering, we propose to use machine learning methods to influence over data redundancy and grouping i.e. Self Organized Mapping (SOM). Solving such problem involves in tackling the issues like clustering, visualization, abstraction and de-duplication. Here the work involves in the usage of Artificial Neural Network (ANN) for Self Organized Mapping that has a unique features, like construction of maps, self organization to form different clusters dynamically to support the volume, variety and variance of big data. In this paper, a novel technique is proposed that supports Hadoop in classifying or clustering of data using Self Organized Mapping. Map Reduce has always been used in combination with Hadoop, but in this implementation Map Reduce is used external to Hadoop job. Using Map Reduce externally is an advantage as Logical Block Address (LBA) and Hash Tag are obtained easily. From the results we found that this implementation has increased speed, data is structured and redundancy is achieved with improved efficiency.

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Friction stir welding (FSW) process is a promising solid state joining process with the potential to join low melting point materials below re-crystallization temperature. The most attractive reason for this is the avoidance of solidification defects formed during conventional fusion welding processes. The present work aims to evaluate the effect of welding parameters on the tensile properties of 2mm thin sheet 5052-H34 aluminium alloy joints produced by friction stir welding. Taguchi method is a powerful technique for the design of high quality systems. This technique has been widely used in engineering design for its, efficient and systematic statistical approach to optimize design performance, quality and cost over a verity of conditions. The L9 orthogonal array has been used to design the experiments, and the experiments have been conducted in vertical milling machine. The main influencing parameters in FSW are tool rotational speed, traversing speed and pressure applied on the faying surfaces. After welding, the weld strength and percentage elongation have been evaluated using uniaxial tensile test. Based on the experimental data the results are then analyzed by using ANOVA statistical tools. This paper experimentally proves and suggests the optimized process parameter values to attain maximum tensile strength in butt joint configuration.

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Welded joints are used for construction of many structures. Welding is a joining or repair process which induces high residual stress field, which combines with stresses resulting from in-service loads, strongly influencing in-service behavior of weld components. A new method is proposed to reduce non uniformity of molten metal occurring because of pores and residual stresses during welding process. In the proposed model work has been made to attain the uniformity of molten metal imparting vibrations to the work piece which in turn transferred to the molten metal of the weld bead. This results in uniform molten metal with minimal formation of voids or gaps, resulting in increase of strength and hardness of weld bead. Vibration techniques have been used in welding for improving the mechanical properties of metals in the last few decades. In the present, vibrating table setup has been used for inducing random mechanical vibrations into the weld pool during welding. The designed vibratory setup produces the random vibrations in terms of rpm given to the work piece by cam shaft mechanism. An increase in the hardness of the weld pieces in the heat affected zone (HAZ) and weld bead has been observed. The above mechanism is responsible for the improvement in ultimate tensile strength of work pieces welded with vibratory setup compared to without vibration and with vibrations during welding.

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In this study, investigation is carried out to determine the effects on the stress concentration around a cut-out due to reinforcement around the cut-out in a flat plate and a cylindrical shell, subjected to axial and bending loads. The study is further extended, to a flat plate and a cylindrical shell, subjected to compressive load, containing two identical cut-outs along the length to determine the effect on the stress concentration factor, with the variation of the distance between the cut-outs. This study assumes the use of homogeneous, isotropic material. The investigation is carried out using the FEA software package, ANSYS APDL Mechanical. Parametric study is carried out to understand the variation of the stress concentration. Mathematical relations are also established that relate the diameter of the cut-outs to the distance between them at which they cease to influence one another, in a non-dimensional format.

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Nowadays researchers are motivated by Environmental issues caused by several synthetic materials. These issues carved a path for the studies of natural fibers reinforced polymer composite and an option to have cost effective, light weight, high strength to weight ratio material. The ease in availability and fabrication process have attracted many researchers to use locally available natural resources as filler in composites, and to study their different properties for mechanical applications. Ridge gourd fibers were used at different weight percentages in Polymethylmethacrylate (PMMA) matrix. Fibers were pre-treated with alkaline solution to improve the interfacial adhesion. Tensile, Flexural and Impact behavior of composites were analyzed to study the stress transfer in fiber matrix phase. Optimum tensile strength values of the fabricated composites were found at 10wt% of fiber loading and similar results were obtained for flexural strength. Increment in tensile, flexural and impact strength in comparison to neat PMMA was found to be 17.2%, 5% and 600%.

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Industry 4.0 is the latest technological innovation of Germany which aims to improve production capability and flexibility by the integration of intelligent systems in industries. As it says, industry 4.0 is a fourth industrial revolution and it is the emerging topic for the industries and researchers. The term industry 4.0 refers not just increased industrial automation, but also to the cyber-physical systems, the internet of things and the ever-growing link between the virtual and physical worlds in manufacturing systems. This paper presents an approach to how existing production systems that are not Industry 4.0 can be transformed and expanded to Industry 4.0 factory. Within this paper, a concept is presented how production systems can be integrated in different stages and included into an Industry 4.0 environment, even though they did not have interfaces when they would have been manufactured. The concept of transformation is based on cyber physical system gateway and servers. Besides the concept itself, it also presents a validation that demonstrates where these interfaces are previously applied or integrated. We aim to synthesize sophisticated information technologies into factory and manufacturing automation. In the present context, the step wise procedure for supply chain wide transformation and some of the expected beneficial outcomes were also discussed.

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This paper introduces a design of crank case cover using topology optimization powered by ANSYS WORKBENCH and to study thermal effects on the optimized model; for addictive manufacturing. Additive manufacturing technique like 3D printing can fabricate three-dimensional assets directly from CAD Drawings created in any software on a successive level. It could reduce the number of processes parts as well as the material loss for a large extend. The goal is to obtain an optimal design using computer simulation, in order to reduce a 30 percentage of total weight of the component hence achieving a performance improvement and a reduction of material wastage; without any compromise of structural and thermal strength.

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The aonla flacks (Phyllanthusemblica), a fruit rich in vitamin-C, has very high medicinal importance in human life. Further, it is regarded as a highly perishable commodity due to its high moisture content. So it needs special attention for its preservation. Drying of aonla in the form of flacks and powder is one of the widely used methods of its preservation. Longer storage life, and substantial volume reduction are the main reasons of the popularity of its fruits and herbs in dried form. In thin layer drying model for drying a hygroscopic material the moisture ratio during the drying period is calculated by the Half Life Time Method, It is assumed that the material layer is thin enough and the air velocity is high so that the conditions of the drying air (humidity and temperature) are kept constant throughout the material at the average velocity of 0.48 m/s and relative humidity 35% of drying air and the drying air temperature in the range between 400?C to 750?C.The drying models, namely Newton s Model, Page Model, Modified Page Model etc. were compared on the basis of to their statistical coefficients such as Root Mean Square Error RMSE, chi-square and Efficiency EF tosee how close the predicted values were to experimental one. The results indicated that out of these models the values of RMSE and the reduced, chi-square ?2 were found the lowest and values of EF highest with Henderson & Pabis model, defined byM/M_0 =Ae^(-kt) where M and M_0 are the instantaneous and initial moisture contents respectively, The two constants namely shape factor and constant k were obtained using curve fitting for different drying air temperatures in the range 400?C?750?C. Using the experimental and predicted values, the resulting RMSE was found to lie between 0.0382 and 0.0094,reduced ?^2between 0.000132 and 0.00761 and EF between 0.9598 and 0.9985. Analysis of the effect of drying air temperature at constant velocity and relative humidity, revealed the adopted Henderson and Pabis models was in good agreement with the experimental results for all drying conditions taken up in the present study of aonla flacks. This model, can therefore, used to predict the moisture content of the aonla at any time during thin layer of drying process, with reasonable accuracy.

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Diesel engines produce high thermal efficiency and low CO2but release more particulate matters (PM) and NOx which are harmful to atmosphere as well as human beings. In India, these emissions are controlled by after exhaust gas treatment and are regulated by Bharat Stage Emission Standards. The effective technology for NOx reduction is Selective Catalytic Reduction (SCR). In this study selective catalysis is carried out over Mn/Ce/Al2O3 catalysts which were prepared by sol-gel and combustion synthesis methods. These catalysts were coated on honeycomb ceramic samples and characterized by SEM. The coated samples were tested in Single cylinder Diesel Engine. The results showed nearly 60%NO conversion.

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The carbon-copper (C-Cu) composites combine the positive characteristics of thermal and electrical conductivity from Cu, low thermal expansion coefficient and lubricating properties from conventional carbon/graphite. For that particular application, C-Cu composites are widely used as electrical contact devices such as carbon brushes and current collector for railway power collection system. Due to economic and environment concern, activated carbon produced from MPOB oil palm kernel shell (OPKS) is studies as replacement for conventional carbon/graphite in C-Cu composites. This study intended to investigate the effect in term of characterization using different particle size of carbon (<90µm and <150µm) and determine the optimum parameter of C-Cu composites to enhance the physical and mechanical properties. The preparation for producing the sample was started with the OPKS through the crushing and sieving process as well as mixed with copper powder and epoxy resin at selected ratio before it is compacted into shape and then undergoes with warm compaction and post baking process. The effects of different particle size of carbon to physical and mechanical properties of the C-Cu composites were analyzed. It is found that the improvements of the mechanical and physical properties are strongly affected by the fine particle carbon (<150µm) and after passing warm compaction at 150°C and post baking at 200°C conditions. It is concluded that the sample prepared in ratio 65% C (<150µm) + 20% Cu + 15% Epoxy resin with warm compaction 150°C, post baking 200°C condition is the optimum sample parameter to fabricate of current collector.

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This paper were investigate a performance of 2 Dimensional Ultrasonic Vibration assisted Milling (UVAM) toward Aluminium Al 6061. The focus is to find the performance of reduction of cutting force compared to the conventional machining in the industries shop floor. Due to the major effect of cutting force of production in industries, the excessive cutting force problem must be investigated deeply as it will cause shortens tool life and reduces the production rate. A scientific approach has been found in order to reduce the cutting force during machining which is integrating the ultrasonic concept into workpiece. The modeling of vibration cutting ratio has been simulated to find the time force contact and non-contact. Thus, less cutting force could be found. The ultrasonic vibration platform that generated by XY25XS from Cedrat Technologies is travelled in X direction as a feed movement. Thus, the X and Y axis vibration actuate along the workpiece for the machining process. The performance of UVAM in cutting force reduction found the superior benefits of UVAM is come from the alternating cycle’s between tool and workpiece. The comparison between UVAM and conventional machining in reduction of cutting force is 32%. The potential of the UVAM tool wear and tool life will be discussed deeply in finding and next in the conclusion section.

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This paper reports the experimental work carried out to determine the cold flow behavior of a swirling fluidized bed incinerator (SFBI) with Quartz sand as bed particles. Three different sizes of sand particles were studied: 425-600µm, 600-850µmand 850-1180µm for four bed heights: 25 mm, 30 mm, 35 mm and 40 mm. The density of the particles was 2450 kg/m3while the gas superficial velocity (Us) was limited to 3 m/s. It was found that the larger particles exceeded the swirl-able regime and only possessed bubbling regime during fluidization. It was also found that the bed pressure drop was higher for higher bed heights and increased when the bed operates in the swirling regime. The study concludes that bed with the smallest particle size (425-600µm) and highest bed height (40 mm) has the desired characteristics to be used in the SFBI.

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Super super duplex stainless steel has shown excellent performance against corrosion attack. However, in corrosive media, 25Cr super duplex is susceptible to localized corrosion attack, especially in seawater and high temperatures. Therefore, the application of this high price material becomes useless when corrosion is likely to attack. The corrosiveness of media increases as the anion content increases. This paper presents the corrosion mechanism of 25Cr super duplex exposed to a high concentration of sulphate in the salinity of seawater. The solution (media) was prepared according to the same composition as seawater including pH, salinity and dissolved oxygen. The corrosion mechanism was characterized as breakdown potential (Eb) (also known as the pitting potential) of 25Cr super duplex, which is, the potential once reaches a sufficiently positive value. The Eb values of 25Cr super duplex were identified at 4°C, 20°C, 50°C and 80°C, and the Eb values in high sulphate content and in seawater were compared for the same temperature range. The results showed that the Eb values decreased in all solutions at increased temperatures due to the increasing attack of localized corrosion. The corrosion attack become worse as the sulphate content in seawater increase cause the decreasing the Eb value, which indicated that the sulphate anions accelerated the corrosion attack on 25Cr super duplex. The conclusion is, although some researchers claim that sulphate ion inhibite corrosion attack on corrosion resistant alloys (CRAs), but for super duplex alloy, the sulphate ion accelerate localized corrosion attack.

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In the present research, a series of mixed matrix membranes (MMMs) consisting of 6FDA-durene as polyimide phase and ZIF-8 as inorganic filler were synthesized and characterized. The loading of ZIF-8 in the polyimide phase were varied from 5 to 20 wt%. The structural properties of the resultant membranes were studied using X-ray diffraction (XRD), Field Emission Scanning Electron Microscopy (FESEM) and Energy Dispersive X-ray (EDX) Spectroscopy. The characterization results showed that excellent compatibility and good distribution of ZIF-8 in 6FDA-durene polyimide phase were observed even at higher ZIF-8 loading up to 20 wt%.

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In the present work, DD3R zeolite membranes were synthesized on a-alumina support using dip-coating and vacuum-assisted seeding secondary growth methods, respectively. DD3R seeds were synthesized using two different routes; (i) ultrasonic irradiation pretreatment coupled with hydrothermal heating for 1 day at 160 ?C and (ii) hydrothermal heating for 25 days at 160 ?C without ultrasonic irradiation pretreatment. Subsequently, the DD3R membranes were grown on the seeded support in 2 days at 160 ?C via hydrothermal heating method. The resultant membranes were characterized using X-ray diffraction (XRD) and field emission scanning electron microscope (FESEM). The XRD and FESEM results showed that all membranes demonstrated DD3R topology. The resultant membranes were subjected to gas permeation study and CO2/CH4 selectivity of 5.22 was obtained for the DD3R membrane synthesized via vacuum seeding method using DD3R seeds synthesized in 1 day.

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This paper is about a survey on the effectiveness of the portable training set for hajj course (PAHAM) for helping the hajj and Umrah pilgrims to better understand while doing the Hajj and Umrah practical. In Malaysia, most of the travel agency always provide a series of courses every year to assist in understanding the Hajj and Umrah pilgrims before departing for the Holy Land especially Board of Tabung Haji. During practical session, they provide the replica model to help pilgrims to familiarize their selves with the actual situation in Mecca. But the current replica model was found using an iron structure that relatively heavy, not portable and embark more cost of transportation and labor. Therefore, this paper purposely to get the response of hajj and Umrah pilgrims on the portable training set for the hajj course (PAHAM) toward cost reduction and also increase the level of understanding to pilgrims. A survey was conducted involving 244respondentsrandomly selected from Hajj and Umrah pilgrims. The data were analyzed using Statistical Packages for Social Sciences (SPSS V19).The results shows, 85.6 % of respondents agreed (mean = 4.21) that this set helping the pilgrims for better understanding and 86.9% of respondents agreed (mean = 4.27) that this set also helping them more focus while training session. As a conclusion, hopefully, this new portable training set concept for the hajj course (PAHAM) will be used by hajj and Umrah pilgrims from all over the world in order to help them for better understand before departing to the Holy land.

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This paper presents the progress of development of a new twin-type piston expander, (TPE) to be used as an expansion unit for a low temperature organic Rankine cycle (ORC). The lack of suitably suitable available expanders and most of the available expander are commonly limited to a certain range of operation. As an initiative to introduce a suitable expander, and the available type of expanders operation commonly limited for a certain range of operation. Therefore, in this study, an existing unused twin piston compressor has been converted into a TPE, with a few modifications on the compressor on by replacing the compressor valves with a solenoid valve and its ports conditions. The newly developed TPE behavior, functionality and performance are were tested at different inlet temperature and pressure. The preliminary results observed showed that the power produced by the TPE is was proportionally changed to the inlet temperature and pressure, and it is was recorded that the highest power of 3.4 kW achieved when TPE operated at 7 bars with 153°C inlet temperature. Meanwhile, it was also observed that the rotational speed variation depends on the inlet pressure much more strongly stronger than it does on the inlet temperature. The results also revealed that the TPE is feasible to be used as an expander for the ORC system with several improvements before it is adapted into the system.

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Road transportation is one of the causes to bad emission to the air. In order to solve some of the problems associated to gasoline-powered vehicles, an electric-powered vehicle has been produced but such vehicles are not widely used yet. Recently, many inventions and researches have been conducted regarding to the idea of mounting wind turbine system on electric-powered vehicles as one of the solution to decrease emissions and save energy. In the present study, proposed design of wind turbine system will be mounted on a pick up truck, Hilux. The wind turbine system was located at the roof of the pickup truck body. Based from the testing conducted, about 120 watt of the wind power (at cruising speed of 120 km/h) was converted to electrical power. The improvement of blade design and configuration, and energy conversion system would increase the produced electrical power.

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Road transportation is one of the biggest sources of pollution contribute to poor air quality and climate change. Through green and clean vehicle invention, air pollution from vehicles can be significantly reduced. In the present study, air flow characteristics in the pick-up truck’s wind turbine ducting system were investigated. The wind turbine system was located at the roof of the pickup truck body. The 3-Diamensional wind turbine ducting models were developed using Inventor and analyzed by using ANSYS Fluent software. The air velocity at duct’s inlet was set at 16.7 m/s, 25 m/s and 33.3 m/s which are equivalent to pickup truck cruising speed of 60 km/h, 90 km/h and 120 km/h, respectively. At the ducting neck region, the air velocity was slightly increased. The air velocity was significantly increased i.e. three times of inlet velocity with additional of flow guider at the inlet. Wind turbine model can be developed using the optimum blade configuration determined from the obtained simulation results. The improvement of blade design and configuration, and energy conversion system would increase the produced electrical power.

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Fatigue is considered a psychological or mental fatigue type characterized by subjective feelings of a disinclination to continue driving, drowsiness, fatigue, and deduction motivation. Bus drivers in Malaysia have been facing physical fatigue from driving for many years. Therefore, investigating the psycho physiological factor that related to fatigue could improve understanding and management for fatigue in the transport industry. Physical factors are divided by two parts that is upper and lower body. The objective of this study is to identify the cause, determine the level and analyze the physical fatigue on bus driver. There were two methods applied in this study, which were Modified Nordic Questionnaires that represent subjective measurement and surface Electromyography (sEMG) the objective measurement. Results from sEMG showed neck and upper back muscle groups leads to fatigue as the muscle is running out of energy based from the graph. Through the sEMG data, it can determine the level of physical fatigue on bus driver and analyzed the physical fatigue. Findings of this study from the questionnaire data analysis using the Statistical Package Social Science software, it is proved that physical fatigue really occurred to the intrastate bus driver. Results also showed significant correlation relationship between physical and mental.

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Stainless steel of AISI 316L type (SS316L) has been widely used as metallic biomedical implants material because of it offers good characteristics, including high mechanical properties and biocompatibility, and relatively low cost. However, its machinabilty an issue, with relation between cutting parameters and surface roughness is of interest to be considered. Related to this, its corrosion behavior related to cutting parameters also needs to be taken into consideration due to its application in implants. This study investigates the bio corrosion behavior of AISI 316L stainless steel which was machined by face milling at different cutting speeds. The cutting speeds were 100, 300 and 500 m/min while feed rate and depth of cut was kept constant. Initial assessment was done on the surface roughness of the face milled samples, with initial hypothesis that the surface roughness should be constant for all cutting speeds, with Ra to be within 0.8 - 1.2 µm. Bio corrosion test was then performed on the samples by Potentiodynamic Polarization Test under a simulated body fluid (SBF) electrolyte. It was found that although similar surface roughness is expected, the cutting speed affected the surface roughness in which the surface roughness tended to be inversely proportional to the cutting speed. Samples machined at the highest cutting speed was observed to have smooth surface with less defects, such as pits and grooves, compared to samples machined at lower cutting speeds. Related to this, the corrosion behavior of the AISI 316L stainless steel was also affected by the cutting speed during its face milling where the corrosion rate is inversely proportional to the cutting speed.

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Rapeseed oil (RO) spray has very slow atomization due to its high viscosity nature. Although high injection pressure, high ambient temperature and combination of nozzle can promote faster atomization of rapeseed oil spray, another factor that was not discussed is the effect air movement that could positively influence RO spray development. To study the effect of air movement, in particular to generate the swirl (air movement inside the chamber), a swirler was used. Images were captured using a nano-spark shadowgraph photography technique and also high speed video imaging. Macrostructures of diesel sprays such as spray tip penetration length, spray shape, spray cone angle were obtained. Microstructures, such as droplet distribution and size were also studied. Result shows that IDI nozzle rapeseed oil spray has a narrow spray cone angle. The average droplet size is around 20~25µm. The large size of rapeseed oil droplet require assistant to improve atomization and results shows rapid air movement in chamber successfully improve atomization.

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Metal Injection Moulding (MIM) is more like plastic injection moulding but with metals. Lubricated metal powder are prepared with a thermoplastic binder, and moulded in an injection moulding machine into a mould that is very similar to a normal injection mould [1]. After moulding, the “green compacted” moulding material is sent through a de-binding process and then through a sintering process. MIM is capable of producing in both large and small volumes, complex shapes and from almost all types of material including metals, ceramics, inter-metallic, compounds, and composites. With no official binder and also exact value for green optimal criteria in MIM, the process for MIM using powder far from been using massively in machining industries [2][3]. In this study, the 60% of Stainless Steel (SS316L) powder loading with binder ratio 50/50 of sewage fat or fats, oil and grease (FOG) and Polypropylene (PP) will be use and analyse for optimal injection and binder parameter. The objective is to determine the porosity and crack at the surface of the brown part using Non-Destructive Test (NDT) process. The percentage of weight loss after solvent and thermal debinding process also have been identified. Hexane has been used as the solvent to remove binder in solvent debinding process. Moreover, the best temperature for hexane to remove binder in sample has been identified which is 50°C of hexane has been picked as the best temperature compared to 40°C of hexane. Thermal debinding has been used to remove Polypropylene (PP) in sample. Both temperature for thermal debinding has been tested which is 40°C and 50°C. The best temperature for thermal debinding is 400°C because it will produce higher percentage of ferum but lower percentage of oxygen. Forming less number of oxygen content will prebent oxidation on sample.

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Extreme friction often occurs in engine components, causes energy loss and reduces the lifespan of the engine. Changing the engine lubricating oil according to scheduled maintenance may reduce the chances of engine breakdown. In this study, an apparatus to test the effectiveness of the engine lubricating oil was developed. It has a special feature that able to test the lubricating performance when subjected to journal bearing abrasion or camshaft-rocker arm abrasion. The experimental procedure was adopted from the ASTM D2782-02 (Timken Test method). Commercially available small engine lubricant oil with an SAE viscosity grade of 20w-40 (mineral-type) from three different manufacturers were tested. In the first experiment, dead weight of 1-10 kilograms were loaded to investigate the effectiveness of the test lubricant oil against extreme pressure. The second and third experiments were on the erosion measured due to abrasion of journal bearings and camshaft intake lobe respectively. Different lubrication performances were found even though the tested oils had the same viscosity grade.

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In sport therapy, ice bath cooling is a treatment to rehabilitate soft tissue and muscle trauma after a period of intense exercise. Rehabilitation is important for an athlete to maintain their performance at all time. This project is aimed to introduce a proper arrangement of inlet and outlet nozzles of a square athlete ice-bath pool system currently used at the National Sports Institute (ISN), Malaysia. The challenge is to have the most efficient arrangement to lower the temperature of the water from ambient temperature to11°C. In this study, the system is constructed based on the ambience, dimensions and cooling system used in the national institute. Analysis is performed for four (4) arrangements according to different position of inlet and outlet of the water to the pool. Amazingly, analysis shows that the common arrangement of placing the flow inlet and outlet adjacent to each other gives the most inefficient result. The study also prove that the optimum arrangement is a placement that has the longest distance between inlet and outlet of the water. This finding agrees well with the pre-assumption where the higher difference between the inlet water temperature as compared to the outlet water temperature will give higher cooling effect to the system. Quantitatively, 21% improvement of efficiency was achieved by rearranging the inlet-outlet nozzles from adjacent to diagonal corners of the pool. Without any complicated modification of the system, a significant improvement was achieved through this work.

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Micro metal injection moulding (µMIM) can be perceived as one of the key technologies for mass micro manufacturing due to its large scale production capability. In micrometer regime, surface roughness is important in view of the microstructure tolerances and in an application where exposure to friction and wear is necessary. Furthermore, reduction of shrinkage affecting the shape stability in the form of induced warpage is also critical. The use of recyclable-based plastics as binder such as polyethylene, polystyrene, polypropylene and etc. can create a green micro parts manufacturing by recovering waste plastic. Plastic recycling promotes reduction of greenhouse gas emissions and saving the landfill area. For production cost benefits in µMIM otherwise, the mould design should has the capability to fully or semi operated for each injection cycle and the mould should also relatively low in cost. This study focuses on fabricating low cost micro moulds with and without ejector system to cope with the aforementioned issues. The binder system used was polyethylene, mixed with stainless steel powder to form the feedstock. Mould inserts were machined from mild steel block by CNC milling machine and cavity was precisely cut out from mild steel plate through electrical discharge wire cutting (EDM-Wire Cut). The EDM-Wire Cut has the capability to cut the conductive materials with close tolerance and relatively cheaper than other method. The part was in dog bone shape with diameter of 2.84mm and the overall specimen length was 9mm. Horizontal plastic injection moulding machine was occupied to inject the feedstock into the mould cavity. Performance of the fabricated low cost moulds were tested and benchmarked by the part shrinkage and surface roughness value (Ra). Results reveal that the obtained shrinkage was within 14 – 19%, produced from both moulds with and without ejector system. The superior surface finish was obtained in average at 0.5µm from part that injected through the mould without the ejector system.

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Sponge media blasting has become popular among industries which require surface preparation such as equipment and machineries refurbishing, oil and gas structure fabrication and many more. However, sponge media requires a rapid drying system when operating in a wet surrounding. This paper presents modeling of the drying kinetics of sponge media when dried in a swirling fluidized bed dryer (SFBD). Five widely used semi-empirical models were adapted from the literature namely Logarithmic model, Henderson and Pabis model, Modified Henderson and Pabis model, Newton or Lawis model and Verma et al. model. Batch drying was conducted for three bed weights of 0.5, 0.75 and 1.0 kg at three drying temperatures of 80ºC, 90ºC and 100ºC. The experimental data from experiments was fitted to these models before analyzed statistically. It was found that Verma et al. model gave the best fit among the five models with a correlation coefficient of 0.98774 and having lowest root mean square error, RMSE, (0.05049), residuals (0.34423) and reduced chi-square, ?2, (0.002549).

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Leakage is a common problem for pressurized water conduit. Currently available leakage assessment methods require reasonable penetration of accurate metering and simultaneous flow measurements at critical locations continuously for a period. To address inadequacy of accurate flow meters, water levels were measured and converted to flows for assessment in this study. Meanwhile, to enable “simultaneous” measurements at the constraints of metering, manpower and transport, a steady state flow condition is maintained throughout the assessment period. This is done by keeping the driving force of the water conveyance tunnel being studied, which is the generated power of the downstream hydropower plant constant. Then, water balance was applied to the single set of average measurements taken at all critical locations for leakage assessment. This method has proven to be useful in assessing leakage condition for the system with metering, manpower and transport constraints. However, the assessment results may be affected by measurement performance.

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The main purpose of this study was to investigate the silicon (Si) particles distribution of LM6 Aluminum Casting Alloy (Al LM6) cylinder produced by centrifugal casting method. Al LM6 cylinder fabrication started by melting Al LM6 ingots. The melt is then poured into a rotating mould with constant speed of 1700 rpm (100 times of gravity value, 100G) at room temperature. After five hours left to freeze, LM6 Al cylinder is removed from the mold. The result is an Al LM6 hollow cylinder with the outer and inner diameter of 60 mm and 20 mm, respectively and the thickness of 35 mm. The temperatures of the molten ingot used in this study were 690°C, 710°C and 725°C. The microstructure differences due to different melting temperatures observed using an optical microscope (OM). Microstructural observations show that the Si particles content are almost the same on the inside, center and outside the specimen. However, the sizes of Si particles in these three parts are different. The particle size of the specimens has a size larger than in the middle and the outside. The difference in size is due to the low density of Si particles than Al and the expansion of Si particles due to rapid melt cooling rate in the mold during centrifugal casting process. The three specimens with different values of melt temperature shows different size Si particles. The difference of Si particle size and distribution expected will influences the mechanical properties of Al LM6 fabricated.

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