The Vortex-In-Cell (VIC) comes as an alternative of the two major CFD methods, the mesh-based and mesh-free method. As a hybrid method, VIC uses particles as discrete model of the fluid domain (mesh-free method) and also employs rectangular grid system to evaluate the governing equation (mesh-based method). The use of grid allows the use of finite difference stencils to discretize the equation. An immersed boundary model called Brinkman Penalization is utilized as solid boundary condition. The method creates solid mask in fluid domain by the implementation of a mollified step function to distinguish the solid from the fluid region. Therefore, it is possible to simulate flow around multiple complex, moving, and deforming geometries. The performance of the code to simulate moving body is tested by simulating fluid-structure interaction (FSI) and flutter phenomena of long-span bridges. The result of the simulations shows good agreement with another numerical method and experimental work.

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This paper presents a numerical simulation of water falling film flowing over horizontal tubes. The objective of this study is to use numerical predictions for comparing the thickness of falling liquids film on CFD models with a verification of previous literatures. A comprehensive design of 3-D models have been developed and validated by the real application of the falling film evaporator as well as experimental parameters often used in the past literatures. A computational fluid dynamic simulation of the water falling film is presented using the Volume of Fluid (VOF) technique. The Volume of Fluid (VOF) technique is capable of determining the thickness of falling liquids film on tubes surface under the influence of the pitch tube and at low pressures. Four types of CFD numerical models with different pitch tubes of 70.05 mm, 59.05 mm, 47.35 mm and 26.85 mm were used in this simulation. The use of a numerical simulation tool on water falling film has resulted in a detailed investigation of film thickness. Based on the numerical simulated results, it is found that the average values of water film thickness for each model are 0.1858 mm, 0.1904 mm, 0.2052 mm, and 0.2200 mm.

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Several researchers have shown that Computerized Fluid Dynamics (CFD) can be successfully used for mathematical modeling of refrigeration systems. In this paper authors developed a CFD model for a domestic no-frost refrigerator. The conservation equations of energy mass and momentum are solved by using Finite Volume Method in an environment of three dimensional unstructured mesh. Experiments were conducted on a no-frost domestic refrigerator to compare and validate the results of the CFD model. Both the results from the CFD model and experiment are qualitatively similar even though there are certain discrepancies due to some insufficient information available for the numerical model.

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The high cost of conducting research is a significant issue for the successfulness of any research project. For research activities involving flow simulation, the licensing fee for the numerical software and the cost to acquire powerful machine are the main factors contributing to the high cost. This paper reports our experiences in setting up a cost effective way of doing computational fluid dynamics (CFD). The actions involve two areas, i.e., software and hardware. For the software, open source software's are utilized, particularly the OpenFOAM® as the CFD package. For the hardware, a parallel computer made from a cluster of inexpensive desktop computer is constructed. This architecture is found able to meet our requirement in investigating various ?ow problems that include aero acoustics, vibration and wind engineering for ventilation.

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Flow over a square cylinder is numerically studied to understand the effect of reduced velocity to the transverse oscillation under the influence of high Scruton number elastic system of 4.316. For low reduced velocities, the transverse oscillation behavior can be grouped in the initial branch region. In this region, the motion is mainly controlled by the lift fluctuation. For intermediate reduced velocities, the transverse oscillation behavior is grouped in the lower branch region. In this region, its natural frequency slowly becomes significant. For high reduced velocities, the galloping region is observed. In this region, the natural frequency dominated the shape of the amplitude oscillation.

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Proton exchange membrane fuel cell (PEMFC) is energy conversion device especially in future use in stationary and vehicular applications. PEMFC’s provide high efficiency and power density with null emission, low operating temperature, quickly start and long life. One aspect that is crucial to optimizing the performance of PEM fuel cells understands is the physics in the flow field and how changes in flow field geometry affect the performance. Hence, in the present study, a model of PEM fuel cell was simulated to understand the effect of straight and serpentine flow field on performance of fuel cell and to predict the effects of changes in the flow field geometry. Commercial Computational Fluid Dynamics (CFD) software was used to extend a numerical three dimensional model of a single PEM fuel cell. Numerical model assumed as a steady state, including Navier-Stokes equations, phase equilibrium, governing electrochemical equations and energy equation. These equations resolved in order to get flow channel and gas diffusion media characteristics, the local current density on the membrane surface, velocity along flow channel and the temperature of the entire control volume. The results show that the local velocity distributions become more uniform for straight flow field designs compare to the serpentine flow field designs. The simulation work here also gives a good agreement with the experimental results and gave a high confidence for the results in order to determine the effectiveness of the flow field design in PEMFC.

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Ventilation systems maintain thermal comfort and indoor air quality for the building envelopes, occupants and furnishings. The systems often perform in opposite to the design intents despite its high energy outlay. Hence, the need to provide energy efficient buildings without compromising the design purposes had produced various ventilation performance metrics. This study investigates the effect of Local Mean Age (LMA) of air on indoor thermal and hygric balance as well as mould growth. In-situ experiments were combined with computational fluid dynamics (CFD) simulation to assess the indoor hygrothermal and the airflow profile in a mechanically ventilated research store with known history of mould growth. A commercial CFD analysis with the standard k–e model was used in the CFD simulation. The measurement and validation of the model are reported in a companion paper. The study found that hygrothermal profiles in the stacks depends on airflow field. In most cases, high hygric profile is synonymous with elevated LMA. The poorest locations in LMA shown highest thermohygric balance and visible mould growth on the stored items. The findings suggest that LMA has a significant effect on hygrothermal stratifications as well as indoor mould growth risk.

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Transverse vortex induced vibration of a spring-supported circular cylinder with mass ratio of 10 and zero damping translating near a plane wall at Re = 100 is numerically studied. The author investigates three gap ratios. Results show that the size of lock-in zone increases and the peak vibration amplitude decreases with decreasing gap ratio. The peak vibration amplitude occurs at a larger reduced velocity for a smaller gap ratio. The cylinder vibration in the lock-in zone is controlled by either the Strouhal frequency or the natural structure frequency in fluid, depending on the gap ratio and reduced velocity. The time-mean drag in the lock-in zone is always larger than that for an isolated non-vibrating (purely translating) cylinder. The time-mean lift is always positive.

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Single-sided ventilated (SSV) buildings have been always assumed to be less efficient in natural ventilation performance compared to cross ventilated building, thus when a good ventilation performance is required in a building the single-sided ventilation strategy has always been ignored as an alternative ventilation strategy to cross ventilation. It is known that the cross ventilation strategy can generally perform better than the single sided ventilation. However, this is not necessarily true in all cases, due to various factors such as wind direction and façade treatment. The objective of this study is to investigate wind-driven natural ventilation performances for a single-cell room with various façade treatment options. This study explores various façade treatments, and the performance of each façade treatment is evaluated. This study uses computational analysis to investigate the ventilation performances. This research methodology is used due to its flexibility and post-processing advantage. This study found that façade treatments such as wing-wall and balcony can significantly influences the natural ventilation performance of a single-cell room.

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The United States Navy have outlined an unmanned underwater vehicle master plan, which includes nine distinct capabilities for these vehicles, some of which may be suitable for underwater gliders. An underwater glider is a type of unmanned underwater vehicle that has a unique concept of propulsion using a combination of buoyancy driven engine and wings. In this paper, four different wing geometries; swept wing, swept back wing, elliptical wing and delta wing, are investigated to determine a suitable wing geometry for a given mission type. The computational fluid dynamic software, ANSYS FLUENT, was used to determine the glider hydrodynamics at different angles of attack. The delta wing has the highest drag followed by the elliptical, swept and swept back wing. Similarly, the delta wing had the highest lift; followed by the elliptical, swept and swept back wing. Underwater gliders are deemed capable of six distinct capabilities. Appropriate wing types were determined for a given mission based on three glide characteristics, which are stability/manoeuvrability, speed and endurance.

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This study was conducted to obtain a model combustion characteristics of rice husk and plastic bags as a energy source. The characteristics modeling using Autodesk Mechanical Desktop, Gambit, and Ansys - Fluent software. Maximum temperature of gas in the grate bed was obtained of about 1,710 K, in the furnace of about 1,670 K, and the average temperature in the furnace of about 1,086 K. The flue gas CO2, CO, and H2O in the furnace was obtained maximum of about 0.336% (3,360 ppm), 0.305% (3,050 ppm), and 0.132% (1,320 ppm), respectively. It was concluded that the co-combustion characteristics model of RH90 + PB10 produces temperature that meets the needs of a trap on the boiler and flue gas produces a small that is safe for the environment. Thus, it can be the basis for the development of utilization as fuel in the power plant.

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The characteristics of laminar separation bubbles (LSBs) on the SD 7003 airfoil have been extensively studied in the past at low Reynolds numbers. It has been found that the LSB is extensive, especially at airfoil at angle of attack (a) of 4º. To analyze separation, transition and reattachment of flow around SD 7003 airfoil effectively, Computational Fluid Dynamics (CFD) analysis can be performed with suitable transition models. In this article, a modified version of k-kL-? transition model, originally proposed by Walter and Cokljat, has been used with open source CFD tool OpenFOAM for analyzing SD 7003 at Reynolds number (Re) of 60,000. The article investigated k-kL-? transition model with two recently developed variants for analyzing SD7003 airfoil. These two variants are based on Pohlhausen and Falkner-Skan profiles to consider effect of pressure-gradient for natural transition. It has been found that both the variants under-predicted the lift coefficients and slightly over-predicted the drag coefficients. Both of the pressure-gradient sensitive variants gave better prediction of separation of the laminar BL. However, the reattachment locations were delayed significantly. Among the two variants, the Falkner-Skan based variant predicted the reattachment location slightly earlier than the Pohlhausen based variant and thus conforming better with different experimental and computational results.

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The influence of shear stress induced by spinneret geometry on morphology of Kaolin/PESf hollow fiber membranes has been studied. Different extrusion rates at two different rheology properties were introduced on a straight spinneret resulting in various shear rates. The hollow fiber membrane were spun using the wet spinning method to decouple the effect of shear and elongation stress due to gravity stretched drawing and bore fluid rate factors. The morphology of the spun hollow fiber was observed under Scanning Electron Microscope (SEM). Shear rates at the tip of the spinneret annulus were calculated and visualize using a computational fluid dynamics model. Simulation data shows that extrusion rate increment increases the shear rate at the spinneret wall while fluid velocity maximize at the centre of annulus. The maximum shear rate recorded was 431 s-1 at an extrusion pressure of 0.5 bar. It is observed that higher shear rates increases the density of the fingerlike voids and ultimately affect the hollow fiber performance in general.

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The present work presents the implementation of the Fourth Order Runge Kutta and Davis Yee TVD scheme [1, 2] applied to case of flow past through an inlet model. The flow problem treated as unsteady flow problem and solves by use of time marching approach goes to steady state solution. At each time step, the governing equation of fluid motions are solved by Fourth order Runge Kutta scheme, then their result updated through the use of Davis – Yee TVD scheme. The flow domains discretized by use of algebraic grid generation. Two inlet models are investigated. The first inlet model represents compression - expansion wave phenomena. The second inlet model describes an inlet model generates the presence of shock wave interaction in the flow domain. These two cases are compared with the result provided by fluent software. It had been found that The Fourth Order Fourth Order Runge Kutta- Davis Yee TVD scheme represented a numerical scheme which able to produce results as given by fluent software.

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Poor hygrothermal performance exacerbates deterioration risk from mould growth, corrosion and damage to archival materials. Improved microcomputers’ computational power has significantly advanced computational fluid dynamics (CFD) models and research developments in indoor airflow, heat transfer and contaminant transport. Nevertheless, numerous uncertainties exist in the CFD experiments which require adequate clarifications for improved results’ reliability. This paper presents the measurement and validation of a CFD model for the investigation of the hygrothermal performance in an indoor environment with known cases of microbial proliferations. The room, 5.2 m × 4.8 m × 3.0 m high, is air-conditioned and ventilated by constant air volume (CAV) system controlling the indoor airflow and hygrothermal profiles with ceiling mounted four-way supply diffuser and extract grille for indoor air distribution. The methodology combines in-situ experiment and numerical simulation with a commercial CFD tool using the standard k–e model. Microclimate and airflow parameters obtained from in-situ experiments were used as boundary conditions in the CFD. The study shows a good agreement between the predicted and measured indoor hygrothermal profile with less than 10% deviation. The results indicate that the model can be employed for further investigation with high confidence.

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The objective of this study is to discuss the potential of voids in Medium Cost Multi-Storey Housing (MCMSH) for hot and humid climate. The result has a significant to identify the suitable configurations of voids for better passive design strategy. In this study, the performance of voids for MCMSH has been studied by using CFD simulation. This study provides a result of different configurations of voids for the studied buildings. The results suggest the appropriate parameter that affects the enhancement of natural ventilation for MCMSH to be adapted in hot and humid climate. The discussion forms a basic framework of void’s proportions in MCMSH to serve better environmental living environment for the MCMSH’s occupants.

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The emission of CO2 has been dramatically increased within the last decade and is still increasing each year, making it the main cause of global warming. CO2 is mainly created by burning fossil fuels such as petrol and diesel. One of the solutions to decrease the emission is by changing the use of petrol to alternative fuel such as Compressed Natural Gas (CNG) or hydrogen. CNG is primarily composed of methane and also contains ethane, propane and heavier hydrocarbons. Even though natural gas has the lowest carbon emission of all fossil fuel, it still has significant carbon content. On the other hand, hydrogen has no carbon content so the replacement of some percentage of natural gas to hydrogen will reduce carbon emission. This study was carried out in order to investigate the influence of increasing the percentage of hydrogen, as a substitute to methane, to the emission produced in the direct injection internal combustion engine conditions. The combustion of hydrogen-methane mixture was simulated by using Star-CCM+ CFD software. The design of the combustion chamber used is similar to the condition for the combustion of petrol in an internal combustion engine where all the valves were closed. The emission of CO and CO2 from the combustion was observed. The emission results of the percentage of hydrogen added to methane fuel was analyzed and discussed. The results showed a decrease of carbon monoxide and carbon dioxide emissions with the increase of hydrogen percentage. This shows that hydrogen-methane mixture has a high potential to be used as the alternative combustion strategy in transportation to replace the existing non-renewable fuels and potentially able to reduce the greenhouse gas problem.

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Numerous studies have been done in order to get the most accurate result that represents the flow characteristics inside the human trachea. Numerical method was the most favorite type of study chosen to simulate the model due to the complexity of the geometry and difficulties to get the real trachea to do the experimental works. In this study, one actual healthy model of human trachea was reconstructed in order to compare, the different of the velocity and pressure distribution between two types of numerical modeling analysis: Computational Fluid Dynamics (CFD) and Fluid Structure Interaction (FSI) analysis. The model was extracted using the Computed Tomography (CT) scan images to maintain the realistic geometry. Velocity, 1.24 m/s was used at the inlet and the variations of the velocity and pressure distribution along the trachea were observed. The results shown that, the implementation of the FSI technique did produce different result and flexibility of the structure wall did influence the distribution of the velocity and pressure along the trachea.

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Patent ductus arteriosus (PDA) is a condition in which the ductus arteriosus remain opened after birth, causing the blood to shunt through from the aorta to the pulmonary artery. However, due to the complicated nature of the arterial geometry, the flow characteristic inside the PDA is not fully understood, since simplified model are commonly used in researches. This study aims to identify the hemodynamic characteristic in three different patient-specific morphologies. Computational modeling via computational fluid dynamic (CFD) is implemented to predict the blood flow behavior in different PDA morphologies. The result shows that low wall shear stress is observed at the region where the flow recirculation occurs. High wall shear stress is observed in the pulmonary artery due to increase of flow velocity at the insertion point of PDA. The PDA morphologies exhibit left-to-right shunt, which diverts approximately 10% of blood flow from the aorta to the pulmonary artery. The highest shunted blood flow is found in TR LPA morphology. High value of OSI indicates the changes of wall shear stress vector. It is observed that DS LPA has the highest area covered by OSI which presents better hemodynamic characteristic as compared to other morphology.

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The study of the flow behavior of splitting device for horizontal pipeline was conducted by using the numerical simulation. The splitting device is functionally to force the roping flow to become homogenous. The study scrutinized the air flow in the pipeline, and also the air flow with particle which is anthracite injected into air in the pipeline. A piping system with 5 different type of splitting device is simulated to find the best splitting device that can make the roping flow become homogenous and improved the roping problem. The simulation was conducted by using the Ansys Fluent. From this study, it can be concluded that the splitting device, does help successfully in reducing the roping problem in the horizontal pipeline.

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Gas liquid bubbly flow reactors are used in chemical and bioprocess industries to enhance the mass transfer between the gas and liquid phases. In bubbly flow reactors, the mass transfer is most important parameter, which affects the product conversion and reactor performance. Mass transfer can be enhanced by achieving more efficient mixing. One such method is the application of rotation or swirl to the gas liquid mixture. Commercial code, Ansys Fluent 14.0 has been used to simulate the phenomenon prevailing in the bubbly reactors with conventional gas injection as well as rotating bottom plate through which the gas is introduced into the column. An attempt has been made to assess the effect of gas injection and swirl bubbly flow, gas void fraction and shear stress by the use of CFD Code. The results of the investigation showed that the gas void fraction increased with increasing in air gas rate for both conventional and swirl gas injection.

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Leucaena leucocephala commonly known as ‘Petai belalang’ locally and well known as the miracle tree and it has other variety of usage such as pulp and wood productions and reforestation. The main objectives of this study is to determine the chemical composition of small diameter wild Leucaena leucocephala species and to compare its chemical compositionat three different stem portions (bottom, middle and top) and two different parts (bark and wood). The chemical composition, sampling and preparation of samples for these analyses were carried out according to the Technical Association of the Pulp and Paper Industry (TAPPI) standards except for hemicellulose which is the data collected through equation. For chemical composition, Leucaena leucocephala wood and bark were analyzed for extractives, holocellulose, a-cellulose, hemicellulose and lignin for each portion which are bottom, middle and top. Based on the results obtained, it shows that the extractives are the highest for top wood (1.41%) and top bark (4.11%). For the holocellulose, the middle wood (90.61%) and bottom bark (73.14%) are the highest. Meanwhile, for a-cellulose, bottom wood (61.18%) and top bark (66.65%) showed the highest percentages. For the hemicellulose percentages, the middle wood (34.74%) and top bark (5.39%) obtained the highest percentages while lignin percentages are the highest for bottom wood (25.22%) and middle bark (19.12%). This study unveiled the chemical composition of Leucaena leucocephala species and thus showing species can be used in paper production and reforestation.

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This paper describes about practical design and analysis of mango inspection and monitoring using machine vision approach. Simulation and outdoor experiment shows that the project able to detect mango with adjustable lighting and proposed suitable design of quadcopter as the hardware part. The captured image of mango tree’s leaf has approximately 87.35 % similarity with the actual one. In addition, image of mango recorded as 95.56 % similarity with the actual one. The practical design shows the view of the quadcopter and raspberry Pi can be attached together in a single case.

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The aim of this work is to design a low-cost wireless EMG sensor network. The design consists of a portable EMG acquisition system and wearable dry electrode unit, which can be applied for monitoring the forearm muscle movement and hence identify the hand manipulation. The system was designed in a way that it could recognize two types of gestures, which are complex hand gestures and normal hand gesture. The performance of the system is evaluated by choosing the best classifier among four classifiers along with 16 features. Among them, the highest classification accuracy obtained for complex hand gesture was about 56% for KNN with VORD feature. For normal hand gesture, maximum classification accuracy was obtained up to 91% for KNN with LOG feature. In addition, the system was experimented on multiple participants by training the classifier and testing the trained model for both the gestures. The system was able to predict hand gesture with decent accuracy.

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Human gait recognition is an important indicator and are extensively studied research area especially with the aging population and rehabilitation applications. Application of gait analysis ranges from diagnosis, monitoring and early detection of potential hazards such as human fall. There are various types of approaches used in gait analysis including wearable, ambient and vision based devices. Microsoft Kinect sensor is well-known among researchers since it can give depth and normal color images as well. This paper presents a preliminary study on gait analysis of lower body parts. The measurements taken includes step width, step lengths, stride lengths and angles of knee respective hip and ankle while walking. The results showed that the algorithms implemented were able to accurately measure the lengths with low error rate.

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The solutions of stress intensity factors of slanted cracks in plain strain plate are hard to find in open literature. There are some previous solutions of stress intensity factors available, however they are not studied completed except for the case of plain stress. The slanted cracks are modelled numerically using ANSYS finite element program. There are ten slanted angles and seven relative crack depths are used and the plate containing cracks is assumed to fulfill the plain strain condition. The plate is then forced uni-axially the stress intensity factors are determined according to the displacement extrapolation method. Based on the numerical analysis, it is found that slanted angles have inverse effects on the behavior of stress intensity factors. Increasing such angles capable to reduce the mode I stress intensity factors. On the other hand, it is also enhanced the capability of mode II stress intensity factors at the crack tip. Due to difficulty of determining stress intensity factors numerically, a regression technique is used to formulate mathematical expressions which are capable to predict the stress intensity factors in reasonable accuracies.

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Surrounded by an assortment of intelligent and efficient search entities, the hybridization of Particle Swarm Optimization (PSO) and Genetic Algorithm (GA) are proven to be a comprehensive tool for solving different kinds of optimization problems due to their contradictive working approaches. In addition, the two algorithms have achieved a remarkable improvement from the adaption of dynamic parameterizations. In this work, dynamic parameterized mutation and crossover are individually and in combination hybridized with a PSO implementation. The performances of different dynamic parameterizations of the hybrid algorithms in solving facility layout problem are compared with single PSO. The comparison revealed that the proposed technique is more effective.

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GPS is a device that is capable of receiving information from GPS satellites and then to accurately calculate its geographical location. This paper presents child tracking system based on modelling of latitude and longitude coordinate and speed changing tracker. The system consists of a Bluetooth GPS receiver and an android smart phone. Communication between GPS and a smart phone is via Bluetooth protocol which requires the Bluetooth GPS to be paired with a smart phone. The smart phone will extract the coordinate and speed from GPS signal which send using National Marine Electronic Association (NMEA) format. This information is analyzed to measure the distance and speed. The smart phone and the speed is more than 2.8km/h after receive an alarm the location of the child can be track using Google map or parent can be share the information via media social such Face book or Whatsapp. The child tracking model based on latitude and longitude coordinate and speed parameter system has been successfully designed and implemented. It is able to protect the child safety by monitoring the location of the child.

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This paper discussed on the design of an idealized meandering river model. Idealized river meander geometry is constructed using the improved sine-generated curve. This method simplifies the river meander plan form by constructing the meander path as combinations of line and arc with direct reference to practical dimensions. Meander and channel geometries are selected based on the Lower Klang River which is tide-dominated area. Complete computational domain is constructed by joining the river model with semi-circular open sea domain. Topography and bathymetry of river model are also presented. The idealized model will greatly facilitate related researches to better understand the physics and behaviors of tidal rivers with meandering effects.

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This paper deals with the design of sixteen bit division algorithms, programmed by using Xilinx ISE 14.4 software for translating the arithmetic operation for division operation. In recent, many researchers have proposed the algorithms to carry out the computation task in hardware instead of software, with the aim to increase the performance of computation. We explained and translated the non-restoring method for division operation. This method is simple to implement since it requires only adder or subtractor in each iteration. Hence, it does not require any other hardware components such as multipliers and multiplexers. The algorithm is translated into Verilog Hardware Description Language that simulated using Integrated Synthesis Environment (ISE) Simulator and then synthesized using Synopsys Design Compiler. The system will only process unsigned binary division hence producing in fixed point value.

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The combination of MIMO and OFDM gives a very attractive option for high data rate communication in wireless communication system over frequency selective fading. However, MIMO-OFDM also inherent the PAPR problem from OFDM system. We proposed our SCS technique and modified SLM technique to be applied in diversity MIMO-OFDM system for PAPR and BER performance improvement. The utilization of circulant shift codeword from SCS technique with multiplication of phase factor of SLM technique in preparing several candidates for interleaving technique is proposed in MIMO-OFDM system. This approach gave a new solution of reducing high PAPR in MIMO-OFDM system. Moreover, by using diversity MIMO-OFDM which is STFBC, the improvement of BER performance also can be improved until 55%.

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In December 2014, Kuala Krau which is located in the state of Pahang, Malaysia has been hit by severe floods which caused a lot of destruction of property and damage to the project catfish in cages along Sungai Pahang. This study focused on the Kuala Krau area because this area is among the worst-hit areas in Pahang. The study aims to quantify nutrients concentrations such as nitrate (NO3) and nitrite (NO2), and other parameters that are necessary to know because it could affect the health of local residents such as iron (Fe), magnesium (Mg) and Zinc (Zn) as well as to investigate their potential environmental risk. GIS software is used to map the environmental risk assessment at each of the sampling location. The results of the study found that most of the parameter concentration is below the limit set out in the Malaysian Water Quality Standard and the trend of transport for most parameters showed a linear correlation when the river flows downstream, the concentration of the parameter also increases.

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Nowadays, photogrammetry is up against the problem of how to collect the 3D information of a city building efficiently and quickly. In the recent years, the Unmanned Aerial Vehicle (UAV) has been getting more attentions from the photogrammetry industry. The UAV has many good characteristics which can be implemented in many tasks that manned aircraft was unable to fulfill. The aim of this study is to reconstruct a 3D model of the Dewan Agung Tunku Canselor (DATC) building by applying the concept of the UAV Close Range Photogrammetry. The control points were established using the basic angular measurement method which consists of 26 control points at the DATC building. The data from angular intersection were processed using the StarNET software to obtain the coordinates of the control points at the building. The 3D DATC model was successfully developed and the qualities of the 3D model were assessed. The analysis was based on the length measurement from the 3D model and actual length. The residual mean square equation was used to determine the accuracy of the 3D point coordinates of the 3D DATC model. In conclusion, UAV can be used for a 3D model reconstruction in the condition it follows the correct technique and procedure.

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The flood problem is unpredictable disasters that impose severe effects to the economy, environment, health and to human being. Flood in Malaysia is a common problem due to the climate condition itself. It has causes high amount of rainfall produced throughout the year and formed by monsoon and convective rainfall formation. Therefore, as a solution to the flood problem, an improved technology has to be implemented to control the flood impacts. There are many problem associated with rainfall conventional collecting method as the data obtained not accurate enough due to inexact time, non-functioning stations and disappearance data. The application of Meteorological Satellite (METSAT) visible (VIS) images is the latest technique implement in rainfall estimation and flood forecasting that can contribute a wide area of information in forecasting rainfall depth based on cloud Albedo. This study focuses on the correlating between cloud Albedo and rainfall depth with comparing the rainfall data provided by Department of Irrigation and Drainage (DID) in order to estimate rainfall. From this study, the result obtained from correlation analysis is correlation is equal to 20.4% and a linear law-regression equation; y = 0.4239x + 4.18 for Klang River basin; that can be used to estimate rainfall based on cloud Albedo data from METSAT visible images. It can be summarize that high value of Albedo will contribute higher intensity of rainfall based on the analysis that has been carried out. Therefore, the rainfall estimation equation is still considered reliable in estimating the average rainfall depth for Klang River Basin despite the weak correlation. However, in certain rainfall events, the equations may underestimate the rainfall value due the formation of Albedo that appears only during daytime.

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Patients with severe physical disabilities might experience communication difficulties. Some injuries hinder their ability to speak, write and type even though their brain is unaffected. Thus, an alternative means of communication is required to relay the intention of the patient. A ‘nurse call button’ has been widely used by patients at health care centers to alert a nurse or a doctor whenever they need help. However, the key limitation of such system is that it simply produces a beep sound at the specific station and the responder has to visit the patient’s room to identify their intention. Thus, in this project, an alternative communication aid is proposed utilizing widely available handheld devices such as smart phones, tablets and notes. As a result, complex sentences or instructions can be delivered to the intended respondent via several combination of “ON-OFF” signal based on Morse code. In addition, the device can also be reprogrammed according to the user preference. It is hoped that the device would be able to help the patient to communicate to other people in order to fulfill their daily needs.

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Automated monitoring of nutrient deficiencies by computers provides more accurate and precise information on current plant health status, which improves the effectiveness of fertilization management on large scale agricultural projects. In comparison to the traditional method which involves judging the deficiencies by personal observation, it is naturally more costly to hire agricultural experts who are more experienced. Besides, judgments by observations are also prone to misinterpretations, which will lead to incorrect applications of fertilizers. In this paper, the automatic detection via Fuzzy Inference System (FIS) is introduced as an automatic classification system for identifying the type of nutrient deficiencies in plant by emulating the judgment made by an agricultural expert when observing the state of the plant leaflets. The main objective of this study is to propose a design of Mamdani-FIS that models the classification of the deficiency type and severity. Oil palm tree (scientific name-ElaeisGuineensisJacq.) were used as the study case for this paper, and leaflet samples are collected which consists of healthy leaflet and nutrient deficient leaflet that have been preprocessed to extract the inference via the fuzzy logic system. This involves the development of the fuzzy rule base, fuzzification and defuzzification process from the extracted features retrieved from leaflet images. The inputs of the membership functions of FIS consist of the number of red pixels, entropy and correlations. Three types of the nutrient deficiencies which are nitrogen, potassium and magnesium, and healthy leaflet condition was selected as the output of membership functions. The implementation of the system demonstrates a promising outcome, with classification accuracy confirmed to 82.67%. The performance of FIS is further evaluated via sensitivity, positive predictive value (ppv) and negative predictive value (npv) calculation which shows desirable rate of above 85%.

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Tasik Puteri, a man-made lake with an area of 131 hectares is located in Dungun District, Terengganu. The lake was once used for iron ore washing process and has now turned into a recreation centre for people living nearby. Nearly, a decade of industrial scale iron mining operations in Bukit Besi has passed and has caused an impact on the region’s surface water quality. However, no information with respect to the water quality status of this lake has been provided to the public. The aim of this work is to evaluate the physicochemical quality of the lake water. Parameters measured were temperature, pH and dissolved oxygen. Water samples from 14 sampling point with different depth were taken. All the parameters were measured in situ by using Hach Water Quality Analysis Kit and was done according to the guidelines of Department of Environment (DOE) Malaysian water quality assessment with respect to Interim National Water Quality standards (INWQS). Results showed that the pH for almost all sampling point is around 3-4, temperature around 30oC and dissolved oxygen less than 10 mg/L. Based on DOE Water Quality Index Classification the lake was classified as polluted against class IV. This shows the lake is not suitable for recreational activities such as fishing and canoeing but more to irrigation.

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Rambutan (Nephelium Lappaceum L.) wood was found out as an alternative biosorbent of heavy metals. This study is to determine the effectiveness of rambutan wood as biosorbent to treat heavy metal contaminated wastewater. Nowadays, there are many conventional adsorbents prepared using chemicals or high cost methods to remove heavy metals from aqueous solution, however they have limited range of usage. Rambutan wood was collected from trunk of matured trees and thoroughly washed to minimize contaminant during the experiment and finally oven dried at 80oC for 24 hours. The characterization of the biosorbent was performed using Fourier Transform Infrared (FTIR) Spectroscopy. The selected metal solution is copper (II), concentration 1000±2 mgL-1 was diluted to desired concentration. The parameters involved in this study are pH, mass of rambutan wood, contact time and initial metal ion concentration. The biosorption experiment was performed between pH: 2-6, contact time: 30-120 min, quantity of rambutan wood: 0.5 g-2.0 g, initial copper (II) concentration: 2, 4 and 6 ppm. The percentage of Cu (II) ion removal was analysed using atomic absorption spectroscopy (AAS). The best operating condition was found at pH 6, at period 60 min, with the amount of 2.0 g and at initial copper (II) concentration of 6 ppm. It has been shown that rambutan wood is highly effective in removing heavy metal from aqueous solution.

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An attempt towards representation of a nonlinear process dynamic through the use of empirical NARX-OLS approach is discussed in this paper. Structured data mining was incipiently conducted to provide exposure over the process properties elucidated by the plant taken from a MISO control perspectives that is allocated in accordance to various sets of reflux ratio operation. Establishment over the process dynamic identification is made possible via OLS model structure and QR factorization parameter selection technique. An optimization of the resultant finding was then implemented through ERR optimization for comparison study. A good comparable yielded result from the model estimators insinuated the possibility of constructing a well-defined empirical dynamic model through a structured data mining processes without a priori knowledge of the system.

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Daily household chores may not be an issue for a normal and young individual. However, it could be a big issue for those people who have physical limitations such as aged and disabled people (e.g.: wheelchair-bounded individual). Inventions of assistive device or technologies that can help them to perform their daily activities are very crucial for them, so that they can become more independent hence increase their self-confidence. One of the daily chores is laundry activity. Thus, a Smart Cloth Hanger for Disabled using Arduino Embedded System is proposed in this paper specifically to cater the needs of disabled individuals. This device can automatically push out the hanger during sunny day and reversely pull it in during rainy day. Other than that, it also has the function of moving the hanger vertically (up and down) to make it easy for the disabled individuals especially those who are wheelchair-bounded to hang and retrieve their clothes. This projects use Atmega328P-PU to install all coding program that will give instructions to conduct this system properly. Voltage regulator LM7805 is also used to regulate the supply at 5V. Several sensors are used in this project, such as rain sensors and Light Dependent Resistor (LDR) sensors. Other than that, DPDT switch is also used to connect with the secondary motor in order to move the hanger vertically. It is hoped that the device can assist the disabled for a better quality of life and further increase their sense of independence.

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Ground conductivity is a well-known parameter since it is commonly used for the grounding system for the building. However, the effect of solar variation to the ground conductivity is not well interrogated by the society. Thus, earth conductivity (EC) experiment is implemented to investigate the pattern of underground conductivity based on the layer of the soil as internal factor and based on solar variation as external factor. The measurements are taken using resistivity meter Chauvin Arnoux C.A 6471 to obtain the underground conductivity data. Since there are many other factors that affects the reading such as type of soil and salt contents, the measurements are conducted at the same survey site. Besides, the measurement applies 2 methods which are Wenner and Schlumberger method. The preliminary result from this small scale experiment has revealed the optimal range soil depth in the survey area and it shows good correlation between underground conductivity and solar variation. Details of the analysis will be discussed throughout this paper.

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The performance of radio detection and ranging also known as RADAR has been investigated from the other researcher due to space weather effects. This research study is to investigate the variation of VHF/UHF due to solar radiation to the effectiveness of Forward Scattering Radar (FSR) during quiet period. The measurements were taken in mix environment area with four different frequencies in VHF (64 MHz, 135 MHz, 173 MHz) and UHF (434 MHz). The Doppler’s raw data of different frequencies for 2 days within 24hours is collected and plotted by FSR and MATLAB Software respectively. The clutter received is varied during day and night time. This research has calculated the average percentage APD% for four frequencies of VHF and UHF. The percentage analysis of day and night time shows obviously that the higher frequency is more sensitive to the reflection due to shorter wavelength. Besides, the amplitude of signal strength is higher during night time compared to day time. The result has concluded that the low frequency (64 MHz) is more robust to solar radiation due to long wavelength and lack of sensitivity for data transmission. This research as a preliminary for further investigation and research on the variation of radio propagation.

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Application of activated carbon as microwave absorber (MWA) in microwave pyrolysis of automotive paint sludge does affect the products yield at medium microwave power. 10%, 15%, 20% and 25% (from APS weight) of MWA have been used in this study. There were three product phase produced which were solid, liquid which is the total of aqueous and oil and gas. The highest amount of aqueous produced was at 25% MWA while the highest oil produced was at 10% MWA. As for solid char produced, there was only slightly difference with the application of MWA instead of without MWA. Gas produced from the microwave pyrolysis process also decreased with the application of MWA instead of the process without MWA.

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Microalgae has received a noble attention in recent years as an alternative feedstock for biofuel production as its capability to produce lipid and has high growth rate. Biodiesel from microalgae is another route to solve fossil fuel dependence, reduce climate changes and enhance food security. High yield of biodiesel produced from microalgae is dependent on large quantities of neutral lipids accumulated in each microalgae cell. The number of microalgae cell can be increased by manipulating the culture conditions and nutrients feed in term of the concentration. Thus, this present work was aimed to encourage continuous cell division and produced high biomass yield of Chlorella sorokiniana (C. sorokiniana) under nitrogen replete condition in view of its capability to produce lipid. This work also presents the physical and chemical properties of C. sorokiniana. The American Society for Testing and Materials (ASTM) standard methods were implemented to examine the microalgae properties, including proximate and ultimate analyses. Microalgae C. sorokiniana supplemented with nitrate concentration of 43.65 mg NO3-NL-1 was found to have a high biomass yield of 940 ± 10mgL-1 and specific growth rate 0.224 ± 0.001 d-1.In comparison, the lowest biomass yield and specific growth rate was in C. sorokiniana supplemented with 48.90 mg NO3-NL-1 were 760 ± 6 mgL-1 and 0.134 ± 0.001 d-1 respectively. On the other hand, TGA analysis showed C. sorokiniana supplemented with 33.95 mg NO3-NL-1 contains high volatile matter (VM) 68.50 and low ash content 9.77in %wt wet basis than other nitrate concentration levels. While, C. sorokiniana supplemented with nitrate concentration of 43.65 mg NO3-NL-1contains average VM and ash content of 51.96 and 33.39 in %wt wet basis respectively. Similarly, in ultimate analysis, C. sorokiniana supplemented with 33.95mg NO3-NL-1 and 43.65 mg NO3-NL-1 contained carbon content of 46.16and 37.681 %wt moist basis respectively. These result demonstrated that as low as 25% of nitrate increment from control BBM media gained high VM and carbon content. In contrast, as high as 75% of nitrate increment from control BBM media increase biomass yield and specific growth rate which in return lower the VM and carbon content.

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Modelling and Simulation helps industry to get information about how something will behave without actually testing it in real life in real industry scenario which will incur cost. One can compress the time frame, and study the behavior of a scenario without engaging it. The use of this within engineering is well recognized. It became necessity or need in an industry. It plays various roles, from fulfilling the requirement in front end task up to furnishing the needed areas in back end task. In a petrochemical plant especially in Ethylene crackers, training operators to operate plant safely and consistent is a need. Higher number in employees ’migration does play a role in a need of training simulator. When an operator with many years of experience left the company, he brings with himself a valuable portion of knowledge and data and training new personnel will incur money and time cost. The training of ethylene plant new operators now need to rely on senior operators experiences from different plant life cycle and will vary with different trainers. Need of simulation that can represent the real world scenario is a mandatory to give a valuable training experience and loss of billions dollars can be avoided.

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Thermal Energy Storage (TES) system has been established for quite some time and already being used in many places throughout the world. Generally, TES is good for a country because it will reduce the overall maximum demand by restructuring load distribution between peak and off-peak period. However, the electricity tariff such as Medium Voltage Peak/Off-Peak Commercial Tariff (C2) should be attractive so that the user would get the benefit from such system. For instance, the off-peak energy (kWh) rate must be low enough and maximum demand (kW) rate should be the same with the maximum demand for each kilowatt of Medium Voltage General Commercial Tariff (C1). This paper investigate the overall cost, using C1 tariff as a benchmark to compare with the C2 tariff based on the implementation of TES system in Engineering Complex UiTM Malaysia. Extra load, energy and cost as the result of the TES implementation were also evaluated in this study. The maximum cooling load required is 35,000 RTh with maximum cooling load demand is 3,500 RT. The results, showed that the TES system investigated in this study was best used with 100% storage capacity through the use of C2 tariff for optimum cost saving.

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Conditions of space weather are unpredictable. The main reason to monitor the solar activity is to protect the satellites, navigations system and power grid system from breakdown. Development of space weather monitoring platform begin with gathering the several websites into one platform. The space weather parameters are divided into four main areas such assun, interplanetary space/solar wind, magnetosphere and geomagnetic. Website builder used in this platform is WordPress domain by University Teknologi MARA Shah Alam. Raw data taken was analyse and plotted by using MATLAB R2013a. Space and Earth’s Electromagnetism University Teknologi MARA (SEE-UiTM) platform is successfully developed. The platform will display space weather parameters and space weather report in a consecutive day, weeks and month. The platform can be used by students, lecturers and researchers to monitor sunspot activity and geomagnetic event daily, weekly and monthly. It is the first space weather monitoring platform in Malaysia by having database and premium domain. This platform can be more practical, which it can give maximum benefit to the user.

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In this paper the arrays of nanorods and hierarchical ZnO nanostructures were made suitable for large-scale production by electrochemical deposition method in a pulsed mode, which allows to control their morphology by varying deposition modes without changing the electrolyte composition. The crystal structure, morphology, optical and electrical properties of nanorod arrays and the hierarchical ZnO nanostructures were studied. The axial texture and the size of nanocrystallites in nanostructured ZnO arrays, their specific electrical resistivity, the height of Schottky grain boundary barriers, the concentration of uncompensated fully ionized donor impurity, the density of surface states at the grain boundaries and the width of the depletion region were determined. Gas sensitivity to low concentrations (10-200 ppmv) of ethanol vapor in air within the temperatures of 25-400 °C were demonstrated for nanorod arrays and hierarchical nanostructures of zinc oxide. According to the analysis of the structure and the properties of electrodeposited ZnO arrays in a pulse mode, the optimal regime was chosen for the manufacture and the operation of this material gas-sensitive layers in gas sensors.

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In order to optimize the front electrodes of flexible photoelectric converters based on sulphide and cadmium telluride, they studied the effect of annealing on air at 430 °C for 25 minutes on a crystal structure, the optical and electrical properties of ITO films obtained by non-reactive magnetron sputtering method on a polyimide substrate. It was found that the annealing in air leads to the decrease of ITO film preferential orientation degree in <100> direction, which indicates the oxygen concentration increase in these layers. There is also a significant increase in surface electrical resistance from 6.5 O/? to 30.4 O/? after the annealing in air, which is caused by the main charge carriers concentration decrease from 9.8 1020 cm-3 to 2.2 1020 cm-3 and leads to the film quality factor decrease from F = 8.7 · 10-3 O-1 to F = 3.1 · 10-3 O-1. It was shown experimentally that the application of an unalloyed tin dioxide layer with the thickness of 40 nm allows to limit the decrease the quality factor of the ITO/ZnO hetero systems after the annealing in air to F = 5.2 · 10-3 O-1.

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The current models of light-emitting diodes describe only some characteristics and parameters, but do not allow to set their temperature dependences. Therefore, these models do not allow to study the processes occurring in real lamps and luminaires. The article considers the XT-E Royal Blue LED model developed in Multisim environment, which is manufactured by Cree, in which the dependence of its characteristics on the temperature of the semiconductor structure is implemented. The principles of the model creation are described. The results of ampere-voltage and emissive characteristics of a powerful LED modeling are presented at different values of its semiconductor structure temperature. The conclusions are made about the possibility of this model use to study the processes occurring in real LED lamps and luminaries.

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The increase in ageing offshore wells and the continued requirement to maintain operations beyond their original design life is beginning to be a major challenge faced by operators worldwide. This problem is further compounded by the limited availability of well construction records, unknown operational conditions and inadequate through life maintenance. In many cases the large number of wells which may be required to be evaluated can also make the process of developing acceptable integrity procedures challenging. Defining an accurate understanding of the present condition of these assets is essential to ensure that the structural integrity of the well can be confirmed, and the acceptability of extending the life of the asset can be evaluated. This papers focuses on the criticality of the well integrity specifically of the conductor and surface casing corrosion and the deterioration of the annular cement due to ageing on shallow water injector wells. Several structural assessments techniques are proposed for evaluating the in-place strength of the corroded well structures under operational and environmental loads, including the detailed analysis on the annular cement deterioration and its ability to mitigate well loads, whilst providing sufficient barriers for the environment. The initial results of these assessments show allowable stress exceedance by more than 20% in some instances, indicating the requirement for immediate plugging and repair/rehabilitation work. Further refinements are proposed in this paper to reduce the over-conservatisms built in the assessments including the development of non-destructive material hardness based well construction preload measurement tool. The combined use of this tool with integrity assessments listed in this paper will prove to be a streamlined approach to tackling ageing well integrity issues in this region, with lean resource consumption and effective life extension of ageing wells for continued operations.

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RepRap (Replicating Rapid Prototyper) is an open-source 3D printer which current revolution from rapid prototyping technology. The technology has become well-known to the public and starting to widely commercialize in the market. The low cost and flexibility of the open-source 3D printer become the alternative for making three-dimensional parts. The advantage of using this technology is that the user has a complete freedom of controlling the process parameters of the fabricate product. Despite of being a low-cost 3D machine, there is no extensive study of the performance on this technology. This paper investigates the impact on process parameters for tensile strength using polylactic acid (PLA) material. Parts were printed using newly developed open-source 3D printer with Repetier-Host software by manipulating three parameters which were layer thickness, shell thickness and printing speed. The printed parts were tested under tensile test machine and the analysis from ANOVA shows that the shell thickness contribute higher significant impact on tensile strength.

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In this paper, the fabrication step of poly (vinylidene fluoride) trifluoroethylene P(VDF-TrFE) thick films deposited on flexible substrate are being described using rod Mayer method. Polyester film being used as the substrate where a sandwiched layer of electrode-piezopolymer-electrode thick film is deposited on. The thick-film is then annealed at 100 °C and polarized at 100 V for the film with a thickness of about 18µm, being inspected under EDX, FESEM and XRD. The flexible piezoelectric transducer is able to generate a maximum output power of 0.711µW at an external electrical load of 1M? with a maximum peak voltage of 843mV when pinching between two fingers with a force of 5N.

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Malaysia fishing industries are heavily dependent on the fossil fuels to satisfy its energy demand. Fuel cost of fishing vessels normally accounts for more than 50% of the annual operating expenses. With the increasing of global fuel prices, the future of this industry has exposed fishermen to uncertain future. Nowadays, clean burning alternative fuel such natural gas has become a great interest for fuel saving. A duel fuel diesel engine is a diesel engine that has been fitted to use compressed natural gas (CNG). Dual fuel engines provide numerous potential advantages such as cost saving, fuel flexibility, lower emissions, better efficiency and easy conversion of existing diesel engines without major modifications. This paper describes a study to reduce fuel consumption by introducing a dual fuel diesel and CNG for Malaysian offshore fishing vessel. An analysis of fuel consumption reduction is presented, together with stability assessments. The results reveals that dual fuel diesel can provide noticeable lower fuel consumption compared to existing diesel engines and stability assessment signify that the conversion to dual fuel engine has no adverse effects to vessel stability.

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Experimental research on joining of grey lamellar graphite cast iron to low carbon steel specimens is being performed under various diffusion welding parameters and variables to examine the effects on their microstructural and mechanical properties. Optimum conditions that produce excellent welding characteristics shall be established, the diffusion process mechanisms observed, the inter-diffusion coefficients and the activation energy of the diffusion system investigated. One of the expected outcomes from this research is to establish the methodology to produce the ultimate weldability of cast iron to steel. This paper updates the progress of this research; the research started with the preparation of the materials and the equipment involved. Base materials used were verified against the inspection/mill certificates by conducting microstructural, compositional and basic mechanical testing. Preliminary studies on diffusion welding experiments were conducted on a few specimens of the materials involved. Although initial few specimens failed to produce credible joints, further investigations on equipment unique characteristics led to making the right adjustments on the parameters and procedures that finally produced good joints on subsequent experiments.

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Solar water heater has been widely used in domestic and industrial sectors to harvest the available solar radiation daily to produce hot water. Computational analysis on performance of solar water heater has been trending up to offset the higher cost of experimental measurement. A 3D computational fluids dynamics (CFD) model was developed and validate with experimental results. The average hot water temperature simulated at 1.00PM until 5.00PM varies from 49.0oC to 54.9oC, while average PCM temperature varies from 53.0oC to 64.8oC. The CFD models developed shows a good agreement of 6.7% and 7.1% simulation error for hot water temperature and PCM temperature respectively. The simulation model developed can be used as a prediction tool for solar energy research and to reduce cost on development of experimental test rig for solar collector experiment.

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The aim of this research is to study the mechanical behavior of natural fiber kapok with fiberglass. In this research, the weight of the kapok is determined by the weight ratio of 1:20 of the woven roving fiberglass weight. The condition of the woven roving and kapok in variation of proper sequence on top of another layer by layer. The sample is then being tested to determine the best mechanical properties of the sample compare to raw fiberglass composites. The sample were undergoing tensile test, impact test and flexural test. The surface morphology properties were done with Scanning Electron Microscopy (SEM). The mechanical properties (flexural strength, flexural modulus, tensile strength) were found to increase as the fiber content and layer increased. Composites loaded with higher fiber content and layer have better fiber-matrix interfacial bonding than those with lower fiber and layer loaded.

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The drive for cleaner, more efficient and cost-effective powering options for container vessels is inevitable in the face of its rising demand and substantial greenhouse gas (GHG) emissions. In this paper, the main challenges of the container shipping industry are established, leading to identifying alternative powering options. A detailed and objective comparative analysis conducted establishes some important implications of these options for deep sea-going container vessels. From the analysis conducted it was found that despite its high bunker costs, low sulphur fuel oil such as marine diesel oil (MDO) could potentially be a transitional option for deep sea-going container vessels in the short term as it does not require any retrofit of vessels. With stricter emission limits looming, deep sea-going container vessels using LNG as a fuel will rapidly increase due to its high emission reduction potential, lower costs, availability, and reliability. A long term solution will require a departure from current practices in the maritime industry alongside a heavier reliance upon established and dependable technologies such as nuclear, solar and wind power.

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This research focuses on the study of impact third harmonic salient pole synchronous generator by using sinusoidal PWM (SPWM) technique. The methods used for this research was the analysis method of an SPWM of AC signal, analysis of a Voltage-source inverter with SPWM output and Fourier analysis of an SPWM. These methods were compared by discussing their ease of implementation, by analyzing the output of the third harmonic of various output voltages and currents, and the third harmonic distortion (THD). The simulation results showed that the SPWM techniques had higher total harmonic distortion as compared to the SPWM coding technique.

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