This research proposes a development of embroidered dual band textile antenna that could integrate wearable telecommunication device with a garment. The proposed antenna could operate at 2.4 GHz and 5.8 GHz of WLAN applications. Two versions of the presented antennas are developed from the conventional rectangular patch. Two types of slot structures are loaded on each antenna and the antenna performances are investigated. The research uses silver patted nylon and cotton wearable as conductive and nonconductive materials. Both antennas have successfully achieved reflection coefficient of less than -10dB at the targeted bands. Besides that, the antennas have directional pattern with a gain of more than 2.5dBi. Moreover, antenna performances on bending conditions of 200, 300, 400, 500, 600, 700 and 800 have been carried out in simulation in terms of the reflection coefficient. The proposed antenna could be potential for closed point to point communication such as wireless power transfer for pacemaker application.

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The design of a high gain Planar Inverted F Antenna (PIFA) with two different frequencies for medical pacemaker is presented. Two PIFA designs have been optimized to be operated at ISM band of 2.45 GHz and 5.8 GHz respectively, under tolerable reflection coefficient of less than -10dB. Both of the proposed antennas are developed from copper plate with a simple structure of rectangular patch. All design and simulation has been carried out using Computer Simulation Technology (CST) Microwave Studio Suite. The simulated and measured results of the fabricated antenna on reflection coefficient, bandwidth radiation pattern, and gain are presented to validate the usefulness of the presented design. The 2D Anechoic Chamber and Agilent Technologies Network Analyzer have been used for the measurement. Both 2.45 GHz and 5.8 GHz antennas have successfully manage to achieve high gain of 6dB and 8.2dB respectively with a directional beam pattern. The presented ISM PIFAs could be potential for point-to-point communication using wireless power transfer technique for medical pacemaker application.

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In this paper, a consolidated view of genetic algorithm approach from the perspective of steganalysis system on text based environment is presented. Thus, this paper is tries to measures the detection performance based on genetic algorithm method and statistical method in order to classify the analyzed text as stego text. Three aspects such as time taken, average of cost function and average of mean and standard deviation have been used to measure the performance methods between statistical and proposed GA based. Experiments have shown that proposed of genetic algorithm method gets better performance than statistical method, especially in detecting a short analyzed text. Thus, a finding shows that the proposed genetic algorithm method on analyzed text is promising. For further work, it is suggested that the accuracy rates of detection process on larger sizes of analyzed text through other intelligent methods should be investigated.

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Mechatronics engineering is a broad discipline involving the integration of mechanical engineering, electrical engineering, telecommunications engineering, control engineering and computer engineering. It is well-known that laboratory or hands-on works enhance the learning process in this class. This study proposes the development of low-cost anthropomorphic robotic hands, namely the Spring Hand and EMG Hand for the introduction to mechatronics engineering courses. The robots have a close physical appearance as human hand and the utilization of the robotic hands in learning basic mechatronics concepts will make the studying process more fun and spark the students interest. The developed robotic hands are low-cost and incorporated with infrared, force and muscle sensor, Arduino UNO board and servomotors. Experiments results from the proposed robotic hand are presented in this paper.

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Electromagnetic energy harvesting holds a promising future as an alternative energy in order to power low power devices. RF energy harvesting systems has been carried out by many researches and efforts have been put into converting RF into usable DC. This paper is a comprehensive review paper which covers the antenna modules and rectifier modules which are being utilized in RF energy harvesting systems over the years. Both the antenna modules and rectifier modules are put into comparison and critically analyzed. From the comparisons made, the gaps and challenges are further discussed in detail.

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An index to compare supercomputers is proposed in the study. This index is based on the concept of technical efficiency and is developed adopting a non-parametric technique, e.g. Data Envelopment Analysis. The index is used to calculate the technical efficiency of 500 high-performing computing systems listed in the TOP500 supercomputers database. Finally, statistical analysis is performed to assess the weight that some supercomputers characteristics have on their efficiency.

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The focus of the stereo matching algorithms development is commonly on eliminating unwanted aspects such as noises, occlusions and unwanted regions. In this paper, a segment-based stereo matching algorithm is introduced, Double Stage Filter (DSF). DSF is a hybrid algorithm which involves the basic approaches such as block matching, dynamic programming and median filter. The main feature of DSF is concern on segmentation and merging process. These processes are to remove the noises and horizontal stripes of raw disparity depth map. Segmentation process of DSF algorithm is to segment the optimized raw disparity depth map into several parts according to the pixel colours. Merging process is to combine the segmented segments into a disparity map. The datasets used for the DSF algorithm are from Middlebury Stereo Vision page and captured by LNC IP stereo camera. Results obtained are analyzed by various methods and functions such as system of Middlebury, Similarity Structural Index Metric (SSIM), Peak to Signal Noise Ratio (PSNR) and Mean Square Errors (MSE).

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This study is a continuity of previous research done by the author which is to validate the simulation results. As the simulation results has shown disturbance in the action potential (AP) signal when electromagnetic radiation (EMR) appear, therefore, it is essential to undertake an experiment to validate those results. As using life specimen will lead to ethical issues, the author has choose robotic arm experiment setup because the main concern in this study is the disturbance on the signal which is measurable through the robotic arm signal. GSM phones are placed really closed to copper wires connecting the robotic arm at certain degree of orientations. The results show significant displacement of matchbox by 0.2 to 1 cm from specified region when radiation source appear. There is also significant voltage increment of 0.4 V on DC signal of robotic arm when phones at 2250 orientation. The GSM phone radiation is possible to interfere with harmonious function of APs.

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Mobile phones nowadays become ubiquitous device and not only a device to facilitate communication, with some addition feature of hardware and software. There are many activities can be captured using mobile phone with many of features. However, not all of these features could benefit to the in processing and analyzer. The large number of features, in some cases, gives less accuracy influence the result. In the same time, a large feature takes requires longer time to build model. This paper aims to analyze accuracy impact of selected feature selection techniques and classifiers that taken on mobile phone activity data and evaluate the method. Furthermore, with use feature selection and discussed emphasis on accuracy impact on classified data of respective classifier, usage of features can be determined. To find the suitable combination between the classifier and the feature selection sometime is crucial. A series of tests conducted in Weka on the accuracy on feature selection shows a consistency on the results although with different order of features. The result found that combination of K* algorithm and correlation feature selection is the best combination with high accuracy rate and in the same time produce less feature subset.

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Commercial CubeSat kit is widely used to simplify CubeSat design process and shortened development schedule by providing standard and reliable hardware architecture. However, project team still needs to coordinate subsystems integration. It becomes more difficult for undergraduate students because they may not familiar with the components used in the kit. Price of the kits is also expensive, especially when converted to Malaysian Ringgit. Research is done to investigate suitable hardware and software architecture and design low cost Command and Data Handling subsystem (C&DH) kit with short learning curve. The kit will consist of hardware and software that is popular among university students and allow less coordination during development. This paper presents the current C&DH architecture for CubeSat and the selection of hardware and software components for the C and DH kit. The kit will be cost effective and convenient to be used by students.

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A new family of almost four-phased sequences with perfect periodic autocorrelation function is proposed. It extends the array of the known almost four-phased sequences both for the periods grid and for the structure via a slight increase of the peak-factor, the value of which is not greater than two. The generation algorithm for the sequences of this family is developed and can be easily implemented on any standard configuration computer.

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Global computational grids nowadays are suffered from ossification problems due to the following fundamental challenges related to different existing solutions in grid computing: scalability, adaptability, security, reliability, availability and manageability. The management difficulty is due to heterogeneity, dynamicity and locality of the resources within global grid networks. Large-scale grids make the fundamental problem of resource discovery a great challenge. This paper presents a self-resource discovery mechanism (SRDM) that achieves efficient grid resource discovery and takes advantage of the strengths of both hierarchy and decentralized approaches that were previously developed for grid based P2P resource discovery. P2P systems offer potential strengths such as self-organization, self-healing, and robustness to failure or attacks. Unfortunately, the majority of existing Distributed Hash Table (DHT) based P2P overlays are lacking of attributes range queries that are familiar in resource discovery lookups. The proposed model builds an effective distributed hierarchy that providing scalable, decentralized resource discovery and allocation as well as load balancing for distributed computing using large-scale pools of heterogeneous computers. Fundamentally, SRDM employs the spatial index and partitions the overlay space to build a distributed quad tree; each computational resource in the network can calculate its Nodepower. Next, it encodes the information about each node s available computational resources power in the structure of the links connecting the nodes in the network. This distributed encoding is self-organized, with each node managing its in-degree and local connectivity via its available Nodepower. Assignment of incoming jobs to nodes with the freest resources is also accomplished by sampling it.

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The emerging research conducted on silicon photonics has emphasized its potential to utilize low cost, mature and mass productive CMOS processes. Among all of the silicon photonics devices, the silicon modulator is one of the important components in optical communication network. In this paper, Multimode Interference (MMI) device is used to develop the Mach Zehnder Interferometer (MZI) structure of the optical modulator. The electrical part of the modulator utilizes the forward biased P-I-N structure. The effects of varying the waveguide s width of the MMI couplers to the performance of the MZI optical modulator on Silicon-On-Insulator (SOI) were investigated. The analyses were done on the insertion loss (IL), extinction ratio (ER) and modulation efficiency (VpL) of the device. The investigated waveguide s widths were 3, 4 and 5 5m. Largest waveguide s width of the MMI, which was 5 5m demonstrated the best performance with IL of 3.63 dB, ER of 28.81 dB and VpL of 0.0315 Vcm.

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Partial Discharge is a phenomenon that indicates cables or joints deterioration in an electrical transmission or distribution system. Mechanical damages, voids or contamination in the insulation of cables or joints may contribute to the degradation thus emission of PD is present. The electromagnetic pulses emitted may represent the condition of the insulation. Current PD detector designed using Patch Antenna with combination of FPGA and ADC is capable to pinpoint the PD source however to ensure the reproducibility between PD detectors, a calibration method has to be established.

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The Tangent Delta utilizing Low Voltage High Frequency Alternating Current is a method to test cables insulation durability. Phase shifts between the current and voltage across the cable are utilized to obtain the Tangent delta measurement. Advantages of this method compared to the market equipments are that the experimental setup is shrunk and special resolutions are improved. This method can measure as short as 1 meter HV cable s. This method was calibrated using cables manufactured with imperfections to distinguish various severities and also with a good cable as benchmark. A calibration curve was established by correlating the HFAC tangent delta measurement system s results with a 50 Hz marketed measurement system. The HFAC method is then used to measure actual field samples taken 20 meters away from a breakdown. Failure Analysis and HFAC result corresponds with the insulation measured being aged.

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Health monitoring system is commonly implemented to continuously track human health condition. Heart rate and body temperature are two important parameters to maintain a vital life. In this study, a wireless monitoring system by using Bluetooth low energy device called Bluno is developed to monitor both parameters. The entire system comprises of several parts which are heart rate sensor using photoplethysmography (PPG) and temperature sensor that are connected to Bluno, and a computer for a graphical user interface to display the measurement. The suitability of two different types of PPG sensors which are visible green light and infrared sensors for heart rate detection is also been compared in this study. The comparison was done on the skin of the fingertips and the result shows that both sensors give a similar heart rate reading when applied to the fingertips simultaneously. On the other hand, the temperature sensor is tested on the respondents to evaluate the time taken for the system to capture the right skin temperature. Based on the result, it shows that the temperature sensor needs about 35 second to read a stable body temperature.

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The nature of constrained resources of sensor nodes, beside of the inherent vulnerability, led to proposing many lightweight cryptosystems in Wireless Sensor Networks. In this paper, we have traced the use of appropriate cryptosystems for wireless networks and covered different cryptographic protocols of main primitives, which are Encryption, Digital Signature and Key Agreement. Our unique integrated categorization of the proposed lightweight cryptosystems would be useful for those cryptologists who are developing lightweight and applicable schemes for Wireless Sensor Networks.

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The impact of rain weather in the images will make it complicated to distinguish in the environment surroundings using an outdoor camera. Moreover, single image plays important role in numerous areas such as in object recognition and detection, enhancement, noise removal and weather condition removal. Rainy weather of outdoor images and videos reduces the visibility, performance of computer vision algorithms and other outdoor activities, which use for extracting features and information from images. Most of the previous review papers focus on the video techniques and raindrops which adherent on the surface and in the images. This paper presents a review of restoration rain streaks detection and removal from single image which has different techniques used in video and includes the result of the implemented experiments using three images.

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For a long time, outcome-based strategy is used as a basis of health standard in wellness program. However, in the case of mHealth participatory sensing the strategy is not always pertinent because the user of the platform is not limited to patient only, but also by a person who used the system for wellness maintenance, and by the stakeholders that collect and analyze information. To improve community s engagement on health wellness and maintenance, we propose myCommHealth that emphasizes on progress-based strategy. myCommHealth is an open data collection platform using mobile devices and allow community and stakeholder to collect, analyze and submit or share health related The objective of this paper is two-fold: First, to explore the design principle behind progress-based strategy for user engagement in mHealth participatory sensing system. Second, to propose myCommHealth, a proof-of-concept prototype that incorporate intrinsic incentive, feedback, and self-monitoring tools to improve user participation in wellness and health-maintenance campaign.

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Nowadays, conventional Metal Oxide Semiconductor Field Effect Transistor (MOSFET) has been undergoing major improvement. This improvement is about the introduction of technique that buries the Buried Oxide layer in an MOSFET. This method is known as Silicon-on-insulator (SOI) and it is believed to be able to suppress the Short channel effect (SCE). The SCE is a trigger to diminish the electrical characteristics of a MOSFET device and by introducing this buried oxide layer, it can suppress this SCE. With SCE suppressed by buried oxide layer, electrical characteristics of an MOSFET can be improved; thus the performance of the device can increase tremendously. In this paper, Silvaco ATLAS and Silvaco ATHENA modules have been used. ATHENA module is used to design the structure layout of SOI MOSFET device. Meanwhile, ATLAS module is employed to extract electrical characteristics of design structure of the device. Conventional PMOS Bulk MOSFET and SOI PMOS was designed and constructed. These two electrical results have been observed and analyzed. As a conclusion, the SOI PMOS device is clearly superior compared to the bulk PMOS device.

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Nowadays, transcranial magnetic stimulation (TMS) has been used to treat major depression and migraine. Integrating transcranial magnetic stimulation and electroencephalogram (TMS - EEG) may provide beneficial information. This paper introduces the experimental design, experimental setup and experimental procedures to differentiate the repetitive transcranial magnetic stimulation (rTMS) and without TMS over N100 (N1) and P200 (P2) peaks with regards to auditory attention. New experimental design, setup and procedures are developed to elicit N1 and P2 through the recording of EEG signal with the excitation of neurons from TMS and pure tones. Wavelet transform is implemented as feature extraction for the selected data. Four features are used for the classification. The classification is based on J48 decision tree performed using WEKA to distinguish between without TMS and rTMS. The result between without TMS and rTMS (in attention condition) showed 98.85% accuracy meanwhile between without TMS and rTMS (no attention condition) showed 99.46% accuracy.

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Fabrication of single-walled carbon nanotubes (SWCNTs) polymer composite based thin film passive saturable absorber was demonstrated using a simple solution casting approach. The fabricated thin film is integrated in erbium-doped ?ber laser (EDFL) in ring cavity and generate soliton pulsed laser. The performance of the generated pulsed laser was recorded with the central wavelength of the self-started stable soliton pulses spectrum at 1556 nm with 4 nm of 3 dB bandwidth and the calculated time-bandwidth product (TBP) is around 0.350. The soliton pulse starts to lase at pump power threshold of 125 MW with a repetition rate, pulse width, average output power, pulse energy, peak power and signal to noise ratio of 15.15 MHz, 710 FS, 0.031 MW, 2.05 PJ, 2.72 W and 50 DB, respectively.

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Wireless power transfer is a method of transferring electrical energy from power source to electrical load without any wire connections. It is used to supply the power on electrical devices without any physical connection except air as the medium transfer. In this paper, the design of wireless power transfer charging system for electric vehicles using inductive resonance coupling method will be presented. The purpose of this project is to develop a prototype of electrical vehicle (EV) charging system by wireless power transfer using inductive resonance coupling method. Besides, the performance of wireless power transfer prototype using this method will also investigate. This paper are carried out with the theoretical studies of inductive resonance coupling method, design proposed, circuit simulation and prototype development. The prototype were consists of a few components which are power supply, transmitter/receiver coil with circuits and charging circuit for EV battery. Observation from the prototype experimental show that, power supply can be transfer wirelessly through transmitter and receiver circuit using inductive resonance coupling principles. Other than that, the performance of electrical vehicle charging system are depends on distance of transmitter and receiver coils, period of charging and amount of power sources.

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This paper investigates the factor influencing the design of vibrotactile sensory substitution system for prosthetic hand. The coin motor is used as the vibrotactile stimulator because of its smaller size and cheaper price. This study is to develop a vibrotactile system to study the possibility for finger localization feedback. Three types of stimulator configurations and three level of vibratory frequency were tested in this study, which are vertical, rounded and u-shape configurations. Seven subjects were participating in the experiment and total of 255 stimuli were given to each subject. The results demonstrate that U-shape configuration and higher vibratory frequency is the best vibrotactile placement for finger localization feedback.

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In the development of the microprocessor architecture, the focus is given more on the microprocessor s performance parameters such as speed, size, cost and power consumption, while less attention is paid to the reliability of data. With the advancement of semiconductor technology node, internal components of a microprocessor are also prone to soft error due to sensitivity to glitches and noise. This paper presents an internal implementation of the fault-tolerance design for a low-end microcontroller. The UTeMRISC Microcontroller is chosen for this research and the fault-tolerance is designed based on the error correction code (ECC). The design is focused on the implementation of Hamming Code and Single-Error-Correction Double-Error-Detection (SEC-DED) Code that are synthesizable in the Field Programmable Gate Array (FPGA). To evaluate the performance and functionality of the design, a number of pre-defined faults are injected into the Fault-Tolerant module at three different locations in the UTeMRISC Microcontroller architecture. Based on the experiment results, the embedded fault-tolerance design has produced acceptable error-recovery rate with the optimal operating frequency is peaked at 60MHz. The evaluation shows the promising results are obtained after comparison into error recovered and time latency. Overall, the integration of the fault-tolerance module in the microcontroller architecture offers a good starting point to create a reliable plat form in the embedded system design.

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SOI MOSFET has currently become a trend for low power devices such as palmtops, cell phone, and other devices because it has a lot of advantage in terms of speed, density, and performance gain. Various efforts have been done to continue the progress in shrinking dimensions and higher-frequency performance will be driven by the market application. Reducing the size of SOI MOSFET will reduce the power, body effect, and parasitic capacitance, and increase the density and so on. This project focused mainly on the source/drain doping abruptness of SOI MOSFET. The doping abruptness was varied to find the best doping profile since the device was shrinking. In order to vary the source/drain doping abruptness, there were several problems to be encountered, which were increase in resistance, increase in threshold voltage, small sub-threshold slope, and others. The purpose of this project was to design the SOI MOSFET with an ideal doping profile and to investigate the impact on threshold voltage, current, and sub-threshold slope due to the variation of source/drain doping abruptness of SOI MOSFET. This project was designed using Silvaco Athena and Silvaco Atlas. Silvaco Athena was used to simulate the device structure and Silvaco Atlas was used to obtain the device characteristics of SOI MOSFET. This whole project was implemented on an SOI MOSFET doping abruptness dependent with a gate length of 21 nm.

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In this paper, a reconfigurable THz patch antenna based on graphene is presented, whose resonance frequency can be changed depending on the applied voltage. The antenna is located over an array of split ring resonators (SRR) also made of graphene; this array actually behaves like a metamaterial. By exploiting the possibility of changing the chemical potential of graphene, independently for the patch and for the array, both bandwidth and radiation properties are optimized. The radiation properties of the proposed layout are then enhanced by introducing an extended hemispherical lens.

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This paper proposes a personal dictionary based on augmented reality where the user has the opportunity to create and handle his/her own customized dictionary. In addition, users have the opportunity to share their dictionaries and download dictionaries handled by other users stored in the cloud. The main concern of this paper is about assisting researchers to understand well scientific/technical articles or papers they are reading. A system/application implemented on a smart phone with the Android OS is provided to snap the text using the smart phone camera and extract the inquiring word from the camera image. In case the extracted word has matching records in the existing dictionary stored in local database, a list of definitions is proposed. And definitions in the list are sorted based on the vote index algorithm proposed in this paper. In case the word does not match with any record, the user has the choice either to add new definition, tags and field in which that word is defined; or to perform search in Google. The proposed system/application appear to be a very helpful and handy assistant that will help researchers to have less struggling to understand scientific/technical articles or papers they are reading.

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The voltage that generated from piezoelectric cantilever is dependent on the magnitude of vibration source and the resonant frequency. In order for the AC electrical energy that derived from the oscillated kinetic energy source to be used for powering electronic devices, it needs to be rectified to DC. Full wave rectifying bridge using conventional diode is a popular choice for its simplicity and ready availability, however at low level output voltage that generated from piezoelectric energy harvester, it would not be able to perform the function because the voltage level that generated could be less than that required to operate the diode. Therefore low voltage operated rectifying circuit is crucial for piezoelectric energy harvesting application. This paper discusses on a few rectifying circuit to compare their performance and it shows that a MOSFET active switching circuit has the higher AC to DC power conversion efficiency compared to other conventional rectifying circuits.

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Piezoelectric micro-generator (MG) is popular due to its high output power density compared to other means of energy harvesting mechanism; however the current generated is relatively low. In the other hand electromagnetic MG is capable to generate higher output current per unit of electrical output power. By combining both of these MGs, they would complement each other in improving the total efficiency of the energy harvesting system. It is verified from the experiment that the hybrid system reduce the capacitor charging time compared to individual system.

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In many engineering applications extended surfaces known as fins, are used to enhance convective heat transfer. The problem of natural convection heat transfer for perforated fins was investigated in this work. An experimental study was conducted to investigate the natural convection heat transfer in a fin plate with circular perforations. The investigation is conducted to compare heat transfer rate of rectangular fins (15 fins) with a size of 100x270 mm embedded with circular vertical shaft. The patterns of perforations rectangular fins contain of 18 circular hole. The temperature distribution was examined for an array of rectangular fins. Experimental results show that the temperatures distribution along the non-perforated fin decreased from 49 to 42oC but for the perforated fin with hole diameter of 20mm, temperature decreased from 67 to 47.4oC with low power (200W). The temperature drop along the non-perforated fin decreased from 170 to 122oC but the temperature drop for perforated fin with hole diameter 20mm decreased from 170 to 101.7oC with high power (900W). Also, when the perforation diameter increased the decrement of the temperature between the base and tip of the fin was increases. Furthermore, when the perforation diameter increased, the heat transfer rate and the coefficient of heat transfer also increased.

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Over the past few decades, global expansions of industrial activities significantly has increased the concentrations of some gases in the atmosphere, such as Carbon Dioxide (CO2) from flue gas, which tend to warm the earth s surface. One of the technology is gas separation using membrane can remove the CO2 from flue gas to prevent the danger of global warming. However, in the flue gas, there is water vapour content that causes the membrane to swell. Thus, for this study, in order to increase the durability and performance of membrane for CO2/N2 separation, the hydropobic membrane is purposed. This study focuses on the effect of the addition of adipic acid on the hydrophobicity of the isotactic Polypropylene (iPP) membranes. The results show that membrane prepared without addition of adipic acid produces highest contact angle, CO2 permeability and selectivity which are 1120, 22.01 GPU and 1.59 respectively. For morphology by using Scanning Electron Microscopy (SEM), observation on the increasing adipic acid shows increasing in pore size and the pore size distribution.

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The synthesis of nanomaterials have attracted a great deal of attention these recent years due to their wide application in many scientific and technological field. Silver nanoparticles, among all other metals, have been investigated because of their unique optical, electronic and chemical properties that depends on their shape and sizes. The main objective of this work is to study the effect of reducing agent to surfactant ratio on the morphology and optical properties of silver nanoparticles. It is believed that the ratio of reducing agent to surfactant plays a significant roles in controlling the size and shapes of the synthesized nanoparticles. In this work, the silver nanoparticle was firstly synthesized via chemical reduction method of AgNO3 with the help of Sodium Borohydride as a reducing agent and Cetyltrimethylammonium Bromide (CTAB) as a surfactant. Different concentration of CTAB and NaBH4 were used in this study ranging from 0.5mM to 1.0mM and 2mM to 4mM, respectively. From this study, it can be observed that high concentration of NaBH4 to low concentration of CTAB produces a larger particles as the presence of CTAB at low concentration in the solution is not enough to inhibit the rapid growth of AgNPs. Meanwhile, the opposite effect were observed at low concentration of NaBH4 to high concentration of CTAB where the AgNPs formed are much more distributed as the growth of silver atoms were inhibited after the reduction process occurs. The low concentration of NaBH4 causes the reduction of silver ions to be at a slower phase, giving time to the CTAB to form a barrier and inhibit growth of AgNPs and thus, avoiding agglomeration. The different reducing agent and surfactant concentration used give rise to the effect of reducing agent to surfactant ratio towards the morphology and optical properties of as-synthesized AgNPs. The resulting AgNPs were then characterized by X-ray diffraction analysis, Field Emission Microscopy (FESEM)and UV-vis analysis. Results from UV-Vis showed the highest absorbance peak at ~410 nm which indicates the silver nanoparticles formation. From the result obtained, it can be suggested that the best ratio of reducing agent to surfactant is at 2.00 with NaBH4 and CTAB concentration at 3 mM and 1.5 mM respectively. At this ratio, the distribution of AgNPs are more improved with less agglomeration.

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The effect of carbonation temperature on thermal properties of the prepared activated carbon using oil palm kernel shell (OPKS) impregnated with phosphoric acid was studied. Porosity plays an important factor for activated carbon performance as a catalyst and it is developed from relatively high temperature during carbonation process. However, too high temperatures may result in widening of micropores and burning off the activated carbon. OPKS/H3PO4 activated carbons were prepared at 5000C, 6000C and 7000C with high impregnation ratio by weight, 2.5:1. The thermal behavior of these prepared activated carbon were analyzed using Thermal Gravimetric Analysis (TGA) and the functional groups develop during the preparation were studied using Fourier Transform Infrared Spectroscopy (FTIR). Results FTIR indicate the changes in the surface functional groups were manipulated when they are impregnated with activation precursor and carbonized at high temperature as comparison made with un-impregnated activated carbon. TGA analysis shows major thermal decomposition occurred only after the sample was heated up to 750:C. This indicates samples prepared are thermally stable.

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Double-porosity is an important feature in soil due to its influence on the migration of fluids within the soil. Conventional ways of measuring fluid saturation involves intrusive use of equipment that may disturb the original setting of the sample being measured. The use of image analysis has overcome this problem but has rarely been applied in research concerning double-porosity soil media. The study presented in this article applies image analysis to study the migration of non-aqueous phase liquid (NAPL) in soil with double-porosoity features. In this study, the laboratory experiments were conducted in a three-dimensional rectangular acrylic model and images were acquired using the photographic technique. Immiscible NAPL was chosen as the fluid applied as it is relatively less studied in double-porosity media compared to miscible contaminants. Aggregated kaolin was used as the double-porosity soil samples. Image analysis was utilized to observe the migration of the NAPL based on migration area coverage, the optical saturation of the NAPL as well as the intensity of the NAPL during migration. The experiments were performed over a range of different moisture content contained in the aggregated soil samples and the effect of different soil moisture content on the migration of NAPL in double-porosity soil was analyzed. The experimental results showed that the rate of NAPL migration will increase as the moisture content increases. In summary, image analysis was found to be a viable method in observing and visualizing the migration of NAPL based on optical saturation, intensity, and area invaded by NAPL in double-porosity soil.

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Unique optical and physical behavior of nanoparticles compared to corresponding bulk materials has gain considerably interest and the research in synthesizing and application of nanoparticles has expanded rapidly over a last decade. This present study reported on the well-dispersity synthesis of nano-size material via chemical reduction of silver nitrate (AgNO3) by sodium borohydride (NaBH4) in an aqueous medium. In this study, there are two parameters that were manipulated which are temperatures; varied from 25 0C until 90 0C and concentration of sodium chloride (NaCl) that was varied from 0.0mM to 30.0 mM respectively. The UV-Vis analysis of silver nanoparticles shows maximum peak were determined at the range of 404nm- 410 nm which is the characteristic of Ag particles. Meanwhile, the morphology of as-synthesized silver nanoparticles (AgNPs) that investigated by using Field Emission Scanning Electron Microscopy (FESEM) reveals a spherical particles size with the size range of 20 nm-160 nm. Analysis of AgNPs diameter by using Image J reveal that the smallest nano-size AgNPs is at 3.0 mM NaCl and at temperature 450C which is ~50 nm.

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Enormous quantities of waste-cooking oil (WCO) are generated and discharged into environment in diverse countries without proper treatments, especially in Malaysia, it may cause negative impact on human life and ecosystem. However, the WCO pre-treatment reveals rich fatty acids, e.g. oleic, palmitic and linoleic compounds can be used as a potential feedstock of biobased-productions, like biodetergents, etc. The renewal of WCO as non-petroleum sources using alkaline hydrolysis technique (ALHYT) as secondary processing was conducted in a bath stirrer flask at various process parameters. The highest biodetergent yield (90%) was found by the alkaline concentration of 5 M, treatment time of 40 min. and operation temperature of 70?C. The essential properties of the waste cooking oil biodetergent (WASCOB) was examined using ASTM D-460. The WASCOB provides impressive results compared another biosurfactant sources, and the restoration of WCO can be considered as a replacement of fossil derived surfactants for future biodetergent.

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Being an abundant natural resource that covers three quarters of the earth s surface, water still a major issue, as less than 1% of fresh water is actually within human reach. Solar energy, most recommended renewable energy source is widely used in desalination fields. Solar distillation, particularly solar still is expected to solve this fresh water production problem without causing any fossil energy depletion, hydrocarbon pollution and environmental degradation. However, the efficiency of the solar still is debatable. As the main reason of low productivity in a solar still is the low heat transfer inside the unit itself therefore, a thoroughly modification on solar still design is presented based on the scope of increasing the heat transfer process inside the unit. Significantly, introducing optical controlling techniques together with focused sunlight receiver and having the process to operate under low pressure have speed up the rate of production within 10 hours of day light. However, the presence of focused sunlight receiver is not seem to improve the production of the solar still yet an increase value is recorded.

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Hydrocarbon transport system in oil and gas industry faces major challenges of flow blockage resulting from hydrates formation and wax depositions. To ensure efficient and economical hydrocarbons transport from wellhead to processing facilities, flow assurance is important in planning and designing of flow transport system. Flow assurance challenges in offshores increase with water-depth because of the surrounding low temperature. Flow assurance thermal management techniques include insulation, pipe burial, electrical heating, and hot fluid circulation. A survey on thermal management techniques employed in oil and gas industry with their various comparative advantages and disadvantages focused on achieving economic pipeline design was conducted. The review showed that the most cost effective method of thermal management technique is pipeline burial and thermal insulation but less effective down deepwater. Electrical heating is effective at all length and at various ambient conditions but expensive. Hot fluid circulation is economical and maintenance friendly with less technical risk but less effective when compared with electrical heating.

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In this paper, optimize the vibrational analysis of power train by decoupling method in the field of automotive. Power train (Engine and gear box) is typically connected to the chassis by three or four rubber mounts. Ideal engine mounts should isolate engine vibrations caused by engine disturbances in the engine speed range and prevent large engine movement from shock excitations from vehicle accelerations, braking and road undulations. The design of power train/mount system involves selection of stiffness coefficients, location and orientation of the individual rubber mounts. Rubber mount location and orientation is decided by designer based on packaging constraints. The goal in this project is to find the engine mount stiffness values corresponding to natural frequencies and mode shapes of the power train system/mount system. CAE find stiffness values and coordinates corresponding to natural frequencies by optimization.

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Disassembly line balancing problem (DLBP) is the factor of remanufacturing industry to improve their effectiveness on part demand. The application of HRRCD’s (Hazard-Reuse-Recycle-Collected-Disposed) heuristic rule will solve the problem of disassembly line by improving the line efficiency and reducing balance delay. A case study from truck’s remanufacturing industry will apply the heuristic rule, which it will improve disassembly line efficiency and decline idle time. Observation from real truck disassembly line will apply in time study and the results show that HRRCD based disassembly line balancing method is the best method to optimize the truck’s disassembly line.

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Hard disc drive (HDD) is known as a main device in a computer. In order to produce a high quality HDD, the source of unnatural variation need to be identified and controlled during manufacturing operation. In this research, simulation and modeling approach was utilized for analyzing the statistical process control (SPC) chart patterns of unnatural variation associated to its root cause error. Initially, the computer aided design (CAD) software was used to model a HDD component and to analyze the source of unnatural variation in manufacturing operation. Then, the artificial data streams for SPC were generated mathematically using MATLAB programming. The process started with normal (in-control) condition and can be followed by sudden shifts when there is a disruption of unnatural variation such as loading error, offsetting in cutting tool, and inconsistency in pneumatic pressure. The design parameters of artificial data streams can be manipulated in terms of window size (WS, length of data streams), magnitude of shifts (Sigma, size of unnatural variation), initial point of shifts (IS), and cross correlation (?) for bivariate data. The results indicated that the generation of artificial data streams can be adapted effectively to various condition of unnatural variation. Generally, this research has provided an useful methodology for a quality practitioner in identifying the source of unnatural variation based on the SPC chart patterns.

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Statistical process control (SPC) chart for variable is a powerful tool, which has been widely implemented for quality control in precision parts manufacturing. It is known to be effective in analyzing whether a manufacturing process lies within a stable or an unstable condition. In current practice, the conventional SPC chart will only detect an unstable process based on one point out-of-control. Unfortunately, this situation is too late for avoiding defective parts and leading to increase waste of materials. To overcome this issue, various studies have been focused on designing the SPC schemes based on control chart pattern recognition (CCPR) method. This advanced SPC scheme has improved the speed for detecting an unstable condition. Nevertheless, a broad of set studies in this area revealed that synthetic SPC samples have been utilized in analyzing the control chart patterns, which is limited to common causable patterns. In this research, a methodology to design a CCPR scheme using an original SPC data has been studied. Based on a case study in metal-stamping operation, the study involves (i) an identification of the unnatural variation for the critical-to-quality variables and (ii) an identification of the design elements for CCPR scheme. The sources of unnatural variation are investigated based on man, method, material, and machine. The CCPR scheme is designed using an artificial neural network (ANN) recognizer model. This methodology will be useful for industrial practitioners in identifying the root cause error in stamping-based operations based on its specific SPC chart pattern.

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Wind energy is being considered all over the world due to the clean characteristics that it possesses and prevalent virtually everywhere in the world. With the current existing technology, a wind turbine could only harness a small portion of energy from the available wind. The amount of harnessed energy could be significantly decreased, if proper wind energy assessments (i.e. micrositing, geographical condition, wind regime characteristics, etc.) were not performed carefully and effectively. As previous studies have shown that, most of the projects which seem to be unfeasible were due to environmental problems such as appropriate site selection, and not technological problems such as wind turbine design. This study presents and discusses the main factors to be considered when undertaking wind energy project in any potential site, so that significant amount of energy could be harvested.

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Whole-body vibration (WBV) is the vibration energy transmitted from a workplace machine or vehicles to a person’s body. The path of this vibration can be either through a seat or by standing on a vibrating surface which can cause health injuries or disorder. This high daily exposure increase the risk of long term health effect, particularly low back back pain (LBP) injury. Due to poorly and limitation on previous international standard on transient shocks which recognize the transient shocks to be dangerous to the lumbar spine, the ISO 2631-5 (2004) was produced as the only current standard that can be used to analyze shocks properly. Thus, proper research on WBV towards LBP problems was done. The determined of vibration exposure levels of lorry drivers using ISO 2631-5 (2004) standard according to route and type of lorry for loading and unloading activities. The future of vibration difference between type of lorry and route was shown in order to find the subjective correction by qualitative and quantitative analysis. Data collected by Larson Davis Vibration Meter (HVM 100) was and Tri-Axial Seat Pad Accelerometer was analyzed by BLAZE program. The value of daily equivalent static compression dose, S_ed and the R factor gain by calculation. Then, IBM Statistical Package for Social Science (SPSS) used to analyze the Modified Nordic Questionnaire. Found that, there are high risk of health adverse toward lumbar spine according to the value of S_ed. The different level of exposure for R factor was according to year’s exposure. Different year’s exposure related to different level of health risk by value of start working age. Thus, several ways of minimizing the exposure such as frequent health monitoring, employer provide training and job rotation as well as with installation the vibration dampers on equipment was also useful. On other hand, new guidelines of vibration exposure level suitable for off-road lorry drivers in Malaysia can be produced for future studies.

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The main intention of this research is to investigate the achievability of oil palm frond fibre to be utilized as an acoustical control panel. All the chopped oil palm frond fibre is treated with alkaline treatment (2%) to interfacial bonding between fibre and binder and such treatment was needed to alleviate such problem. Natural rubber (latex) is used as a binder. These samples are varied in the mixing percentage of latex, which are 40%, 30%, 20% and without binder noted as 0%. The physical properties of the fibre which are density, porosity, tortuosity and air flow resistivity were investigated experimentally to show that these properties will affect the value of sound absorption coefficient (SAC). From the result obtained, the sample with a high composition of binder tends to have high density and tortuosity, but less porosity. From the result obtained, the SAC value at the lower frequency (< 500 Hz) increased as the density of the sample increased. However, the SAC value of the higher frequency (> 2000 Hz) decreased as the density of the sample decreased due to the large porosity within them. Furthermore, the results of the SAC tests show that at lower frequency (< 500 Hz), SAC of the sample increases with increasing in density, but tend to decrease at higher frequency (>2000 Hz) for denser samples. Same as density, the SAC value at higher frequency (> 2000 Hz) increased as the tortuosity of the sample increased. However, at lower frequency (< 500 Hz), when the tortuosity of the sample increased, the SAC of the fibre decreased. The oil palm frond fibre can be considered as good sound absorber at high frequency, but cannot be considered as good absorber at lower frequency since the value of SAC is below 0.70. In general, oil palm frond fibre shows that it’s suitable as an acoustical panel module at middle frequencies (500 Hz – 1000 Hz) and high frequency sound level which is more than 2000 Hz.

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Pressing process can be performed in any circumstances for compaction parameters. The optimum conditions were experimentally evaluated from compression test. These inspections are very useful to determine the variations in the bonding between the powder particles and the effect of compaction parameter on compression strength, Micro hardness and microstructure. Four groups of particle size were selected which were (25,63,100, mix of them) µm. The mechanical properties of the four groups depend on the variations in particle size for powder and the pores between particles. So, it is useful first to present and discuss the results of microstructure to understand the strengthening mechanism. In this study, compression strength value was increased with the increasing of compaction pressure value to (9) tons of all types of suggested groups. After that, it was gradually decreased. The maximum value of compression strength was detected by mix group which was (160) MPa while the particle size (100) µm was the minimum value which was (115)MPa.whereas the groups (25) µm and (63) µm were (150) and (134)MPa respectively.

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Artificial Bee Colony (ABC) algorithm is one of the methods used to solve the flowshop scheduling problem. In order to further investigate the ABC capabilities, we proposed a methodology with the capability of manipulating the onlooker bee approaches in ABC Algorithm for solving flowshop scheduling problem. This paper reviews the analysis of the performance of the ABC algorithm through three different onlooker approaches i.e. method 3+0+0 (three onlooker bees are dedicated to the best employed bee), method 2+1+0 (two onlooker bees are dedicated to the best employed bee and one onlooker bee is dedicated to second best employee bee) and method 1+1+1 (one onlooker bee is dedicated to each employed bee). The simulation results indicated that method 2+1+0 produces best result at low iterations of 102 and below. At high iterations of 204 and above method 3+0+0 dominates the best performance.

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This study deals numerical study of the effect of anti vortex generator (AVG) on the film cooling performance of a circular cooling hole which has diameter (d = 20 mm) on a flat plate. The interaction between the jet cooling air and mainstream will result kidney vortex which will eliminate the film cooling effectiveness. Two types of AVG with different heights (H = 0.5 d and 0.25 d) are designed to eliminate the kidney vortex and investigate best film cooling effectiveness, where each of them is mounted to the flat plate upstream of the cooling hole by changing its lateral positions (A = 0.0 d, 0.25 d, 0.5 d and 0.75 d) with respect to the hole centerline and for each type has different distance respect to hole centerline. The changing of blowing ratio (BR = 0.5-1.0) was considered in this study. Simulation model has been used to simulate a film cooling configuration by using shear stress transport (SST) model. The results have been presented in terms of laterally averaged and maximum value of film cooling comparison graphs, velocity field on x/d = 3.0, vorticity on x/d = 3.0 and film cooling distribution which explained how the results obtained. Cases 04 and 07 gave the best positions for AVG where case 04 gave wide covered for laterally average film cooling effectiveness (? = 0.35), while case 07 gave the highest expand distribution and the maximum value for film cooling effectiveness (? = 0.66).

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The effect of 1 wt % Pr addition on ZRE1 cast alloy was investigated using Optical Microscope (OM), Scanning Electron Microscope (SEM), Energy-Dispersive Spectrum (EDS) and X-ray Diffraction (XRD). The purpose of this research is to investigate the variations in grain size and intermetallics formation with Pr addition, as well as their effect on hardness. The microstructure observations show that the grains became smaller with Pr addition, which lead to the increase of hardness of base alloy. EDS results showed that the base alloy mainly consists of a-Mg matrix and Mg-Zn-Ce as a second phase crystallized along the grain boundaries and when Pr was added, the Mg-Zn-Ce-Pr phase was formed, where Pr combined with the original second phase. The solubility of zinc and Pr in magnesium formed Zn-rich particles around grain boundaries.

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Sustainability, the ability of humans to live within our means, becomes a major concern for engineers and designers now a day’s. Engineering optimization, which uses techniques of selecting best elements from set of alternatives to achieve design goals, is one means for sustainability. Structural topology optimization, which is one type of engineering optimization, deals with finding optimal layout of a structure through optimal material distribution with a given design domain. Topology optimization problems have been formulated and solved by means of compliance minimization. There are some efforts for formulating and solving a topology optimization problem with stress constraints. Though formulating an optimization problems with stress constraints seems acceptable and reliable from engineering point of view it has been facing challenges associated with high nonlinear local stress constraints and design variables. In this paper an optimization problem is formulated to minimize volume based on von mises stress theory subjected to stress constraints for two dimensional problems. A mathematical model which takes into consideration the singularity phenomenon associated with the design variables and stress constraints is developed. The results of the model is compared to the results of the compliance based approach by solving two numerical cases. The numerical results shows that the proposed method has comparable efficiency and accuracy by having less transition elements and securing elements in the design domain free from stress failure.

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Fewer reports regarding the portable FDM machine has encourage the study about the capability of the machine to be used as sacrificial master pattern in investment casting for small production of castings. This study presents an analysis of cracking on ceramic shell during burnout process to determine the maximum value of the hoop stress towards pattern itself and also hoop stress on ceramic shell. There are two types of the internal pattern structure whereby hollow and square in which built from portable Fused Deposition Modeling (FDM) technique with same thickness of ceramic shell. Strain gauge is viable tool in which was attached on patterns and ceramic shells to determine the maximum value of hoop stress during experimental burnout process. This experimental were conducted with variant temperature starting from 30°C until 150°C with increment of 5°C per minute. Moreover, experimental result shows that ABS P400 material strain was increased when subjected to increment of temperature and pressure. This phenomenon happened due to the different value of Coefficient Thermal Expansion (CTE) between the patterns and ceramic shell. In addition, experimental results show that the maximum hoops stress is higher on the square internal structure compared to the hollow internal structure. The hollow pattern experienced 40 % amount of reduction of strain compared to the square pattern. The observation was made that glass transition temperature, Tg between 70°C to 110°C. It was observed that the shell cracking happened on ceramic shell.

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The effect of thickness of vortex gating system on microstructure, velocity and porosity of A314 cast alloy was investigated. Three different thicknesses of 20, 25 and 30 mm were simulated and casted. The data of simulation showed the thicker gating reduced the velocity of the melt. In addition, increased thickness in vortex gate contributes to better eutectic interlaminar spacing. The best quality of casting (less porosity) was obtained with large thickness of vortex gating system.

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Approximately 57% of total production occurs in west Malaysia, 99% in Sabah and about 5 million hectare of area oil palm has been planted. At present, Malaysia is famous in the producing of oil palm in the international market. The oil palm trees are not only provide oil but also raw materials. Among the alternative material resources, agricultural waste like oil palm Mesocarp is selected and known as lignocellulosic materials. In this research, the acoustic absorption of oil palm Mesocarp was measured. The material were mixed with Polyurethane (PU) as binder with four different percentages of 10%, 20%, 30% and 40%. Experimental measurements in impedance tube are used for analysis. Moreover, analytical models namely; Delany-Bazley are conducted to validate the experimental measurements. Results showed that the percentages of binder have positive and significant effects on physical properties. Delany-Bazley model were predicted the absorption coefficient very well in low frequency range. The result also presented that all samples demonstrated higher SAC at mid-high frequency range with the average of sound absorption above 0.5. The sample with 10 percent PU binder shows the best performance in most of low to mid frequency range. The results indicated some potential characteristics of oil palm Mesocarp fiber to be implemented as sound absorption panel.

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This study is about the application of Additive Manufacturing (AM) technologies for the manufacturing of an improved design of Polycrystalline Diamond Compact drill bit body by using Thermo jet three dimensional printing and investment casting. The aim of study is to investigate a faster and effective PDC drill bit manufacturing process without compromising the mechanical aspects of the fabricated model. The conventional fabrication processes could be lengthy and cost intensive for the development of a complex product. With the rapidly developing technologies, the aspiration of manufacturing rate is keep rising and will be higher in future for sure. To overcome these issues, AM is one of the tool between the manufacturing rate and high precision product. In the current study, a computer aided design (CAD) of PDC bit body model that was modified from a previous design was taken and sectioned into parts to optimize the three dimensional printing process. Wax patterns were created using AM in separate sections for minimizing the support structure. Then the drill bit body was casted using investment casting process. The end result was a PDC drill bit body fabricated with steel material.

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Percentage of infill pattern is one of the important parameter in the 3D printing process when flexibility and cushioning is critical. This study was done by focusing on the structure of insoles foot orthosis produced using 3D printing which is one of the methods in additive manufacturing. Thermoplastic elastomer namely Filaflex and NinjaFlex which was printed by using Flashforge 3d printer was in order to determine the mechanical properties of samples with variations of the percentage infill patterns. In this study, the samples went through three type of testing, which are tensile test, flexural test and hardness strength for infill pattern of Filaflex was higher value compared to the ninjaflex where 284.6 N for maximum force with 70% of infill of tensile strength of Filaflex and flexural strength for infill pattern 2.28 N for flexural force with 80% of infill show the effective result of Filafex compared to Ninjaflex result. The lowest hardness of Filaflex 7.8 shows the best structure hardness of foot insoles structure.

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Fused Deposition Modelling (FDM) is the technology that uses an additive manufacturing process to fabricate a product. This study aims to investigate the resistivity of both conductive composite materials through an extrusion process by FDM and calculating resistivity through a variety of tests. The study of the resistance of designing a prototype using conductive composite filaments through the AM process. This analysis more understandable when the basic equations of electricity used, which is V = IR. This equation shows the relationship between the voltage and the resistance, whereas the resistance increasing, the voltage will be decreasing. The test was done in different length, diameter, which is before and after extrusion. This study is also includes taking reading of light intensity for a functional embedded product by using a lux meter. Therefore, the resistivity by length and volume were measured for both materials, conductive ABS and protopasta- conductive filament, from the results found out that the protopasta-conductive filament is 56% more conductive than the conductive ABS.

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This paper presents Polymer Matrix Composite (PMC) as feedstock used in Fused Deposition Modeling (FDM) machine. This study discussed the development of a new polymer matrix composite (PMC) material for use in injection molding machine. The material consists of copper powder filled in an acrylonitrile butadiene styrene (ABS), binder and surfactant material. In this study, the effect of copper powder was investigated as a filler material in polymer matrix composite and ABS was chosen as a matrix material. The detailed formulations of mixing ratio with various combinations of the new PMC are investigated experimentally. Based on the result obtained, it was found that, the weight percentage increment of copper filler affected the viscosity, temperature, velocity, melt flow index and surface tension.

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Ionic polymer-metal composite (IPMC) is an electro active material that bends when being stimulated electrically. Basically, there are two actuation attributes of IPMC actuator had been investigated which are the actuation force and bending degree. However, characterization on multilayer IPMC actuation had been less studied. Based on the preliminary research, double layer IPMC actuator is performing a non uniform actuation where the first actuator bends at higher actuation rate compared to the second actuator. Hence, this research was conducted to investigate the double layer IPMC actuation by adjusting some parameters. They are the thickness of the IPMC layer, voltage supply and current supply. Those parameters had been varied to observe the IPMC actuation. The result of this research shows that as the voltage supply varies, the bending degree of the both IPMC layer become uniform at 4V DC when the thickness is 0.025cm. Besides, by changing the thickness of the IPMC actuator, the bending degree of the IPMC actuator gives a linear trend.

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This work addresses the implementation of an online dynamic cascaded-conditional based optimization for handling model uncertainty occurred in an autocatalytic esterification of Propionic Anhydride with 2-Butanol. The online optimization strategy includes an integration of the dynamic re-optimization mechanism (trigger, i.e. ±5% of conversion and dynamic re-optimizer, i.e. hybrid strategy in maximizing profit), estimator (cubature Kalman Filter) and controller (dual mode-adaptive PID). The re-optimization and control problems are solved separately in cascaded. The re-optimization mechanism is activated conditionally by using trigger. The simulation results show that the proposed strategy offers a large improvement in semi batch reactor performance if compared to the method which the optimal trajectories set point is pre-determined (offline optimization). Moreover, the online dynamic optimization of temperature and feed flow rate trajectories obtained able to sustain the conversion within acceptable range ( on-spec). Meanwhile, the offline optimization failed to handle the effect of parameter model uncertainty thus the end conversion produced is off-spec and can lead to loss in profit.

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Impact is a complicated phenomenon that occurs when two or more bodies collide at a short time period. Impact model is used to determine the responses of the contact bodies due to the impact event. Furthermore, energy loss due to impact can be determined by coefficient of restitution (COR). Although numerous impact models have been reported in the literatures, the works to improve the model are continuously explored to achieve perfection of the impact model. The aims of this paper are to present the methodologies that have been used to obtain the impact models and COR, evaluate on the pros and cons of the previous impact models and determine the potential area to improve the current impact models and COR. The methods to obtain COR from experiment and finite element method (FEM) are briefly discussed. Besides that, several significant impact models developed by the researchers are also compared. It is found that more works to determine COR in oblique and repeated impacts should be performed. Until now, the viscoplastic impact model is considered to be the most reliable in impact application. This review is intended to assist the derivation of impact models in the future that can improve the accuracy and solve the problem in the previous impact models to be applied in various impact applications.

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Fused Deposition Modelling (FDM) machine usually uses an extrusion method of plastic based material in layered manufacturing process. This study was focused on the effects of feed rate on filament flow in the extrusion process. For the first step, testing jig was built to ease the extrusion process were carried out. Testing jig was designed using the FDM extruder which are a major component in this study. Three types of filament were selected in the experimental such as Acrylonitrile Butadiene Styrene (ABS), High Impact Polystyrene (HIPS), and (ABS + Copper) by 3mm diameter size of the filament. From the results of the filament extrusion conducted, feed rate plays an important role in smoothing the extrusion process. Based on the results obtained, it was found that, the feed rate applied to drive the filament into the extruder head should be between 5 mm/s to 15 mm/s approximately. Meanwhile, the high temperature was affected on the filament extrusion flow through the different nozzle diameter of 0.4 mm and 0.6 mm in size. Therefore, the temperature range of ABS and HIPS in extrusion process was 230°C until 250°C and for ABS + Copper at 240°C to 270°C respectively.

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This paper presents the melt flow rate (MFR) of an acrylonitrile butadiene styrene ABS-Copper filament wire for Fused Deposition Modelling (FDM) machine. In this study, the effect MFR of 70 % copper filled in 30 % ABS filament material was investigated experimentally based on the melting temperature, feedrate and different size of FDM nozzle diameter. The melt flow index (MFI) and mechanical properties of ABS-Copper filament through the injection molding machine and Melt Flow Indexer Machine was investigated in the experimental for highest value of the mechanical properties and MFI. Based on the result obtained, it was found that, increment of 75% copper filled in ABS filament material in weight percentage (wt. %) increase the MFR, velocity and length of PMC wire filament material. It can be conclude that, highest temperature and federate is needed to extrude polymer matrix composite (PMC) filament compared to ABS polymer filament material in FDM machine.

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In this paper, modification of simple assembly line balancing spreadsheet was done to accommodate the methodology for solving two-sided assembly line balancing problem. In the two sided assembly line balancing problem, tasks are divided into three main categories; depending on sides position either right side (R), left side (L) or can be positioned at any sides (E). In addition, random task selection is added to conventional priority rules to present the effect of multi-solutions on two-sided assembly line balancing. Tests conducted to evaluate the performance of the spreadsheet methodology has shown that the introduction of the random priority rule has generated better performance results for the two-sided assembly line balancing problem.

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This paper elucidates the second part of the development of Work Movement Task Analysis (WMTA). This part involves improvements of the WMTA previous version and validation test using experimental approach. Methods: Current study comprises of three main objectives; (1) to investigate specific muscle activity subject to the WMTA risk rating (combination of Posture and Load, (2) to determine differences of perceived exertion (Posture and Movement) subject to the WMTA risk rating, (3) to determine differences of perceived exertion (Load and Load size) subject to the WMTA risk rating. A total 14 participants with no previous history of musculoskeletal injuries handled a load (5kg and 10kg) from the low risk to the high risk workstation setting on three simulation trials. For objective (1), Electromyography (EMG) data was recorded during the tasks then demeaned, high band-pass filtered using sixth order Butterworth filter at 25-30Hz then full-wave rectification. Subsequently low-pass filtered using fourth order Butterworth filter at 4Hz and mean absolute values (MAV) were obtained. MAV were applied for normalizing the EMG data with respect to the percentage of maximal voluntary contraction (MVC) for every muscle involves. For objective (2) & (3), perceived effort determined using the Borg’s scale. Results: Experiment I: Workstation height and load variations significantly affected EMG. There was a trend of increasing of muscles activity from Task 1 to Task 3 relative to the WMTA scores; Left anterior deltoid p<0.000, Right anterior deltoid p<0.001, Right upper trapezius p<0.005, Left upper trapezius p<0.001, Right erector spinae p<0.001 and Left erector spinae p<0.000. Experiment II—simulation 1: there was a trend of increasing of muscles activity from Task 1 to Task 3 relative to the WMTA scores. Significant different (p<0.007) perceived effort of the participant for Task 1, Task 2 and Task 3. Experiment II – simulation 2: : there was a trend of increasing of muscles activity from Task 1 to Task 3 relative to the WMTA scores. Significant different (p<0.016) perceived effort of the participant for Task 1, Task 2 and Task 3. Conclusions: The study provides evidence to support the validity of the WMTA tools that focused on the combination of ergonomic risk factors; Postures and Loads, Posture and Movement & Load and Load Size. This tool is expected to provide new workplace ergonomic observational tool with solid experimental validation to assess WMSDs for the next stage of the case study.

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Nanofluid is defined as suspension of nanoparticles in the base fluid. Researchers found that nanofluid improves thermophysical properties of base fluid such as thermal conductivity. However, with the addition of nanoparticles into base fluid also increases its viscosity which leads to augmentation of pumping power. Therefore, better understanding on nanofluid’s viscosity characteristic is essential in order to minimize this drawback. This paper presents the investigations on the viscosity characteristic of carbon nanotube based nanofluids. The weight percentage of nanoparticles were varied from 0.01 to 0.5%. Various surfactants such as polyvinylpyrrolidone (PVP), Gum Arabic (GA) and hexadecyltrimethylammoniumbromide (CTAB) were also included in the present study. R/S Plus Brookfield rheometer was used to measure viscosity of the samples. Study revealed that nanofluids added with surfactant exhibited lower viscosity compared to nanofluids without surfacant. The viscosity also found increases with the increasing of nanoparticles’ weight percentage. Overall, carbon nanotube (0.5 weight %) based nanofluids added with gum arabic has highest viscosity value compared to other samples.

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Various materials such as water, oil heat, ionic liquids and also molten salt are selected to serve as heat transfer fluid. The nitrate based molten salt that has been use in this study consists of binary, ternary and quaternary salt mixture with different weight composition. DTA, TGA and DSC were performed to obtained melting point, thermal stability and heat capacity. The melting point for ternary and quaternary mixtures are closely 100 ºC compared than binary mixture. Quaternary mixture shown the highest result in thermal stability and heat capacity with the value 701 ºC and 4.7 J/g ºC and have fulfilled the targeted characteristic as heat transfer fluid.

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The application of ultrasonic vibration has been extended into the powder metallurgy compaction. Special design of ultrasonic compaction tool was used. In the present study, stainless steel powder was compacted under quasi-static and ultrasonic compression processes. The green compact specimens then sintered using vacuum furnace. In order to investigate the mechanical properties of the sintered specimens, series of compression and hardness tests were conducted. Stress-strain data and surface hardness profile were plotted from both conditions. The sygenistic effect of ultrasonic vibration with high compaction force enhanced strength and surface hardness properties of sintered part. The increase of plastic collapse strength and surface hardness were up to 5% and 2% respectively.

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STEP-NC was designed to replace ISO 6983 G-codes with a modern, associative communications protocol that connects computer numerical controlled (CNC) process data to a product description of the part being machined. STEP-NC is a machine tool control language that extends the ISO 10303 STEP standards with the machining model in ISO 14649 or also known as STEP-NC. The combinations of implementation methods and application protocols defined in STEP and STEP-NC standards provide standardized physical file formats and data access interfaces for those physical file formats that can cover all the aspects of design and manufacturing activities. The data exchanges between different systems will no longer have barriers through the implementation of STEP-NC in the computerized manufacturing environment. It will provide the missing link between CAD to CAM applications. This paper will review ISO 14649 which is STEP-NC through an understanding of STEP which is ISO 10303 standard for the computer-interpretable representation and exchange of product manufacturing information.

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Child neck governs the head kinematic response on impact and therefore greatly influence the severity of head injury in motor vehicle crash. Biofidelic neck model developed using correct child anthropometry is crucial in evaluating head-neck associated injuries. In this work a six year old hybrid III (HIII) child dummy neck finite element (FE) model was scaled down to a three year old (3YO) Nigerian child anthropometry and inertial properties. The resulting neck model was coupled to three year old Nigerian child head model previously developed by the authors. Validation was carried out by pendulum test for flexion and extension test using acceleration pulse of Hybrid III 3YO certification specifications. Neck cable and neck rubber material parameters were determined for the neck response to correlate with the certification corridors of three year old child. The neck response was found to be within the certification corridors. Moreover, the new neck model was found to correlate well with 3YO model of Mizuno for flexion response and hybrid III dummy model for both extension and flexion responses as such it can be applied in evaluating neck injuries of 3YO Nigerian child on impact.

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Polyoxymethylene (POM) belongs to a group of high-performance thermoplastic polymers, which has high specific properties as compared to conventional metallic materials. Due to its own properties and potential applications in various fields of structural components, it is necessary to investigate the machining of POM. This paper present the relationships between the cutting conditions (depth of cut, feed rate and cutting speed). The researcher focuses on interaction effects between the controllable factors and responses during machining of POM material under dry machining condition. An experiment and analysis was conducted by using design of experiment method (DOE). The optimum parameter was determined by measuring the surface roughness (Ra) of each work piece and analyze the result via an interaction of main effect by ANOVA. The researcher were successfully record the optimum parameters which is 4000 RPM of cutting speed, 0.25 mm/tooth for feed rate, 4 mm of depth of cut. By using this parameter, the smallest value of surface roughness is measured -0.0286µm.

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In the SHS process, compaction pressure on the reactant pellet is an important part influencing the thermal conductivity of the reactant. The thermal conductivity of the reactant affects the heat propagation and the heat loss during the ignition and wave propagation of the reaction. The objective of this work was to study the effect of compaction pressure on the microstructure and properties of the synthesized product. An Ni/Al mixture and Ti layer were compacted to produce 100 MPa, 150 MPa and 200 MPa on the pellets and ignited to initiate the SHS process. The microstructure of the synthesized product was observed using XRD and SEM, whereas the properties of the synthesized products were evaluated using a Vickers micro hardness tester. Microstructure analysis indicated that several intermetallic phases have existed in the bilayer product as a result of reactions between Ni/Al and Ti. An increase in the compaction pressure led to an increase in the formation of pores in the synthesized product. The micro hardness of product fluctuated with an increase of the compaction pressure.

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Textiles with integrated electrical features are capable of creating intelligent articles and it can be realized by printing of conductive inks. But, the technologies are still under progress of development thus this paper presents the investigation on the feasibility of printing conductive ink using silkscreen printing. A two points probe is employed to measure the resistance and the functionality of the electronics structure printed is tested by introducing strains via bending test. It was found that the resistances obtained from single layer printed ink track were not as expected whereas the result for the double layer printed ink track shows a satisfactory result. It was also observed that the surface finish for single layer printed ink track were rougher, uneven and bumpy compared to double layer printed ink track. The bending test results were as expected since increasing the strains causing the electronics structure to change the resistance incrementally thus proving the functionality of the electronics structure printed. The used of conductive ink is proven suitable to provide some elastic character (stretchable) and highly potential for wearable electronics application.

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The utilization of energy in office building is mostly for create comfort and health for employee to work. However, it always consume energy excesively which is caused from the utilization of air-conditioning. The high demand of energy adopted from air-conditioning is to dilute indoor air particle. This article is about a parametric study of inlet air supply position for identifying the effectiveness of airflow behaviour of a room to dilute indoor air particle. It was carried out using COMSOL Multiphysics software of modelling and simulation approach. In simulation stage, the first process was to simulate the airflow behavior and the second was to assess its behaviour to dilute indoor air particle. Results from the simulation indicated that effectiveness of airflow behaviour in diluting indoor air particle are affected by inlet air supply position, outlet position and barrier condition in the room. Thus, these indicate that to improve IAQ of a room it needs to properly understand the airflow behaviour.

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Modelling and simulation is one of approaches to study the airflow movement and its effect to particle transmission within the room. This presents a study on the effect of laminar flow on particle transmission in an air condition room. The measured supply air velocity was taken using Davis Anemometer. While, the transmitted particulate matter of diameter = 0.3 µm was using Particle Counter GT-521. Both of the measured values were used as an input in simulating particle transmission using COMSOL Multiphysics software. The simulation process comprise of constructing geometry space of the room, selecting physics module, assigning values and defining boundary, meshing and finally executing and computing the simulation. The results from simulation indicated that the air velocities at the occupant's area are 22.5 % to 43 % below than ASHRAE standard but the airflow distribution at working area meet with the standard. The simulation results are validated with the measured value and found that the percentage differences between the simulated and measured values are within the range of 0.4 % to 8.45 % which is in the tolerable range of 10 %.

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Latest vehicle development demands a solid background in aerodynamics to reduce the unsteady flow. The complexity implied in the vehicle conception especially due to the shaped and accessories that form its geometry creates the validation projects costly. The low speed flow field for a wedge-shaped and armoured vehicle model is investigated both experimentally and numerically. The wedge-shaped dimension is 100 mm X 100 mm X 49 mm which 28° wedge angle. In order to measure the velocity and flow characteristics, a wind tunnel study was performed with wind speed 5.18 m/s and validated using Computational Fluid Dynamics (CFD) simulation software ANSYS FLUENT. Details about the flow field, including velocity and flow pattern, are shown. Further CFD simulation of an armored vehicle model using the similar approaches was performed at speed of 22.2 m/s to predict the flow pattern.

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The enhancement of the accuracy in a 2D-DIC can be related to the image resolution. In a common sense, higher image resolution provides a better result than lower image resolution. However, it is expensive to produce a high resolution images and in many cases they are not necessary. On the other side, measurement accuracy by using DIC is related with the displacement field. In many cases on experimental mechanics, displacement field in an area of interest is usually non-uniform, in which the ratio between minimum and maximum displacement in that area of interest is high. The present work evaluates the accuracy of 2D-DIC algorithms in relation with image resolution and the effect of non-uniformity of the displacement. The evaluation was based on the input images of the algorithms, which were artificial and experimental images. It was observed that both type of input images produce the similar tendency on the effect of image resolution to the accuracy of the measurement. Higher image resolution reduced relative error significantly in case where the minimum displacement in the area of interest is much smaller than the maximum displacement (very low ratio or high non-uniformity of the displacement). However, even though lower resolution image has higher relative error than high resolution image, the effect of resolution is not significant if displacement field tends to be more uniform (the ratio between minimum and maximum displacement in an area of interest is higher than 0.5). The importance of the present result is to determine the applicability of DIC measurement field based on image resolution.

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Advancement in computer aided engineering has made it possible to apply finite element (FE) analysis in crash simulations. Biofidelic dummy FE models are necessary for the application of FE methods in both design and evaluation of cars. Anthropomorphic test device (ATD) and human models are numerical tools designed to imitate real human being response and measure moments, forces and accelerations experienced by human body during crash, which will give data to quantify the severity of injury that the body sustained. While adult FE models have been extensively studied, children models need more vigorous research works to enhance their biofidelity. This paper provides a review on the child FE models with the aim of highlighting the development made so far and work needed to be carried out to enhance the biofidelity of the models. The review is divided in to six parts: child human models, ATD child models, head models, neck models, anthropometry, and model validation.

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To measure the dynamic behavior of material at high strain rates, ranging from 500/s to 10000/s, a Split Hopkinson Pressure Bar was developed. Numerical simulations had been used to verify the performance of the design using 2D axisymmetric model before the SHPB system was manufactured. The numerical model was validated by using measurement parameters of experiments using existing SHPB, which had been carried out to measure the dynamic behavior of St 37 and Al 6063 specimens at strain rates of 3500/s and 4000/s respectively. The results of the numerical simulations fitted the experimental results with difference of less than 10%, which validated the use of the numerical modeling in the design process of the SHPB.

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Nowadays, the demand of the electrical energy is increased due to increment in loading and it is desired to use the existing transmission network to its thermal stability limits. The electrical power system are designed and operated to meet the continuous variation of power demand. The power demand is shared among the generating units and economic of operation is the main consideration in assigning the power to be generated by each generating unit. This paper presents the application Evolutionary Programming (EP), Artificial Immune System (AIS), and Particle Swarm Optimization (PSO) techniques for solving an economic dispatch (ED) problem. The purpose of ED technique in this study mainly to minimize the total generation cost and transmission losses in the system. The proposed optimization technique was validated on 26-bus IEEE Reliability Test System (RTS).

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Fault Detection and Identification (FDI) is a subfield of control engineering which concerns with self-monitoring system, identifying and pinpointing the type and location of failures. This study proposes the application of Kalman Filter for fault detection in quad rotor type MAV. It begins with the development of model of quad rotor, based on rigid body dynamic. The bank of Kalman filters consists of six filters that are associated with the total number of the degree of freedom of the quad rotor. The performance of the fault detection is conducted by simulation using Simulink, Matlab. The result shows that the developed bank of Kalman filters has good performance in detecting a sensor failure during a hovering condition.

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Honey is one a well-known healthy natural products. By image visualization, honeys look quite similar between each other. Hence an electronic device is one of significant instrument that can be employed for detection namely an E-Nose. E-Nose comprises of an array of electronic chemical sensors that capable of recognizing odor profiles. This device is integrated by microcontroller, software and hardware design. The datasets that had been collected in this work were normalized and analyzed using boxplot for feature extraction. The unique features found from the feature extraction were used in Case-Based Reasoning (CBR) as attributes. The result shows that the classification rate of CBR is 100% in accuracy, specificity and sensitivity. These results conclude that different types of honey were able to be classified based on odor profile employed with CBR.

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Nowadays, Kelulut is one of a bee species, yet different in size, it produces a honey that is clearer in colour as compared to natural honey bee. However, study on Kelulut honey grade is not yet extensively explored. Hence, this research aim is to classify Kelulut honey based on smell pattern recognition. In order to sense the smell of Kelulut honey, an E-nose that is comprises of sensor array has been used to measure 2000 samples of dataset from two different types of Kelulut honey. The measured data have been normalized and analysed using statistical method. Then, it has been classified using CBR as an intelligent classifier. It is shown that 100% classification rate of accuracy has been achieved for 2 types of Kelulut honey. The performance measures of CBR in terms of accuracy, specificity, sensitivity have been successfully achieved with 100% performance.

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Ammonia in palm oil fertilizer will affect to water pollution. Nowadays there are many types of fertilizer that have been and are being sold in Malaysia market. The low quality of fertilizer has the highest of ammonia quantity. By using one of significant instrument that was called as Electronic nose (E-Nose), the quantity of ammonia in palm oil fertilizer will be detected. Firstly e-nose chamber was developed by using Arduino, gas sensor array and potential meter. From e-nose with two types of ammonia in fertilizer samples, 2000 of data collected by microcontroller and spreadsheet software. By using mathematical method the data was normalized. Based on 2000 data, the graphical represented by MATLAB software. From the graph of two samples it is shown of two different pattern produced from the graph. Also by using MATLAB software and same data the boxplot will show the differences of data sample. After that, the normalize data was insert to Case-based Reasoning (CBR). CBR was employed by using excel software that was setup with mathematical methods. From CBR the 100% of accuracy, sensitivity and specificity have been achieved. As a conclusion, from the result of CBR, the project is successful to classify the different of palm oil fertilizer type.

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Fish has high quality protein and other essential nutrients and are an important part of a healthful diet. It is important to make sure the quality of fish to avoid food poisoning. There are three methods to know the quality of fish which is sensory, microbiology and chemical methods. Nowadays, some fish monger use formalin to make fish looks fresh and good. Formalin is a colorless strong-smelling chemical substance usually used in industry of textiles, plastics, papers, paint, construction, and well known to preserve human corpse. It is derived from formaldehyde gas dissolved in water. Exposure to the gas and vapour can make irritation to the eyes, nose and respiratory tract. There is quite difficult for consumers to differentiate fresh fish without formalin and fish with formalin. This is because, they look fresh and good but the different is the odor which is the fresh fish still have a fishy smell while fish with formalin do not smelly. Therefore, we use electronic nose (E-nose) to know fresh fish and formalin-based preserved fish. E-nose consists of an array of conduct metric chemical sensors which change resistance when exposed to vapour. The odor-profile of the fish samples were collected based on designated experimental procedure. The measured raw data was then stored in Microsoft Excel data and converted into MATLAB. Then they were normalized and their unique features were extracted using statistical tools. The input features were than inserted into Case-based Reasoning (CBR) library and intelligently classified using CBR method and validated based specific performance measure. The results have shown that the CBR classified with 100.00% rate of accuracy.

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This paper proposes a reduced sigma point transformation for a FastSLAM framework. The sigma point transformation is used to estimate robot poses in conjunction with generic particle filter used in standard FastSLAM framework. This method can estimate robot poses more consistently and accurately than the current standard particle filters, especially when involving highly nonlinear models or non-Gaussian noises. In addition, this algorithm avoids the calculation of the Jacobian for motion model which could be extremely difficult for high order systems. We proposed a sampling strategy known as a spherical simplex for sigma point transformation to estimate robot poses in FastSLAM framework. Simulation results are shown to validate the performance goals.

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Coil arrangement is one of essential part in electrical machine design that affects the torque performance of the machine. Thus, a new stator slot structure of permanent magnet machine called Independent Coil Excitation Permanent Magnet Motor (ICE-PMM) is introduced. Design and magnetic circuit analysis of ICE-PMM is presented. In addition, qualitative comparisons are made with the other conventional types of Permanent Magnet Machines (PMM) which are Slot-type and Slotless rotor. A brief description on the basic concept of the ICE-PMM motor design along with the Slot-type and Slotless rotor structure are presented. The main objective of this paper is to evaluate PMM type that has better static torque with low cogging between conventional and ICE-PMM. Simulation studies of all three PMM are presented in order to evaluate the feature of its flux distribution, flux linkage, flux flow, cogging and static torque characteristics. In a conclusion, the ICE-PMM could perform better as high static torque PMM with lower cogging compare to the other two conventional types.

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In a transformer energisation study, transformer modeling is one of the major challenges. The representation of windings, the modeling of the magnetic iron core and the ability to specify flux are the main focuses. Other than that, the interfacing network, iron saturation, losses, transformer data and the connection should also be taken into account. This paper presents a transformer model for slow-front transients caused by 50 Hz line energisation. Three single-phase 16 kVA, 11 kV/ 250 V distribution transformer models are used. This classic transformer model (include the leakage reactance and magnetising branch) are adopted from PSCAD/EMTDC master library and further modeled by combination of analytical analysis and measurements. Core saturation is modeled using an ideal current source across the specified winding; the saturation curve is constructed using curve-fitting method, generated by MATLAB Optimization. The circuit breaker is modeled using Maximum Closing Time Span (MCTS). For modeling validation, a transformer of same rating was employed as the test object. Since the PSCAD simulation and experimental measurements give similar results, it demonstrates the capability of the model to accurately represent the energisation transient of a distribution transformer.

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Selection of suitable material, fitting for prototype design and pumping rates are three affecting element for cost effectiveness and improve performance of vanadium cell prototype investigation. Therefore, three-dimensional numerical model isothermal computational fluid dynamics (CFD) model of vanadium redox flow battery (V-RFB) is studied. In this work, V-RFB with different electrolyte compartments is proposed and the effect of serpentine flow field is investigated. The performance of two V-RFBs with diamond and square electrolyte compartment is numerically tested. This work has been performed to optimize flow rate, electrolyte compartment design, avoid stagnant fluid and flow field application in V-RFB. For the simulation, the flow was assumed to be incompressible, isothermal, steady state flow, laminar and Newtonian flow. Results show that the application of flow field and Rhombus type electrolyte compartment can facilitate the distribution of electrolyte in the unit cell uniformity and avoid stagnant in the tank. Simulation results indicate the diamond shape and serpentine flow field at optimal flow rate show the most suitable for V-RFBs than square shape.

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