Universiti Teknikal Malaysia Melaka: UTeM Open Journal System
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Output Power Forecasting for 2kW Monocrystalline PV System using Response Surface Methodology
Get PDF Photovoltaic (PV) system is a renewable energy source that not only able to reduce the effect of greenhouse gas towards the environment, but also a highly profitable industry nowadays. To determine the Return of Investment (ROI) of a newly installed system, forecasting is crucial. Thus, the purpose of this study is to produce a prediction model for the yearly output power of the PV system using three environmental elements; irradiance, module temperature and ambient temperature by Response Surface Methodology (RSM). To do so, MATLAB RStool which is consisting of four models; multiple linear regression (MLR), interaction, pure quadratic, and full quadratic is used. The 5 minute sampling size of yearly 2014 weather station data the three environmental elements and output power of a 2kW Monocrystalline real PV system are used for training. Whereas, yearly 2015 data of the aforementioned elements are used for validation. The coefficient of determination (R2) method and root mean square error (RMSE) approach were used to determine the most accurate prediction model. Results show that, full quadratic is the most accurate prediction model with R2 value of 0.9995 and RMSE of 8%. It is hoped that the prediction model introduced can be a viable method to be used by the PV system installer.
FINITE ELEMENT ANALYSIS OF RIB CUSHION POSITIONING FOR EXPANDED POLYSTYRENE PACKAGING
No full textThe home appliance industry often chooses to use expanded polystyrene as a product packaging medium because of its rigidity as well as its undeniable effectiveness in protecting various products. However, the effectiveness of this type of packaging needs to be demonstrated through destructive testing such as side-clamping evaluation. Forklift clamping is a machine test applied to evaluate the packaging of flat screen televisions to ascertain if the model has potential risk. In addition, destructive testing evaluation will be repeatedly conducted until a solution is found. Indirectly, this method increases the working hours and development costs of television packaging. Thus, a cushion with a density of 20 kg/m3 and different rib cushion positions was analyzed to see the existing stress distribution and cushion deformation. The analysis was run using the ANSYS software. The results showed that the rib cushion combination design was the best according to the maximum stress values of 6.222 MPa and 4.056 MPa. All results are presented and discussed. In conclusion, the cushion performance was significantly influenced by the rib cushion positioning
FIXED-POLE ACTIVE PI FILTER DESIGN FOR HIGH FREQUENCY NONLINEAR PLL MODELS
Get PDFA Phase-locked loop (PLL) is a basic control system that attempts to produce an output waveform that can match with the input reference signal in the shortest time possible. A filter is one of the main components in the PLL blocks, and it plays a very important role to determine the range of input frequency that can ensure the system stays in a locked condition. This paper focuses on designing a fixed-pole active PI filter which is suitable for high-frequency PLL-based circuits such as those used in clock generators. As PLL is bound to fall out of lock due to the nonlinear effects from its phase detector, a new approach is introduced in this work which is to combine the linear and nonlinear control method to ensure stability. Having had the phase margin specified a priori, it is shown by simulation that the allowable range of input frequency such that the system remains locked can be expanded
Modeling, Analysis and Control of Chaotic Rucklidge System
Get PDFThis paper presents modeling, analysis and research of chaotic Rucklidge system based on programming interface that has been developed in LabView software environment. This study allows for generating and researching the main properties of chaotic Rucklidge system, focusing on time distribution of three chaotic coordinates and phase portraits. A range of the system parameter with which we can generate different period (controlled) attractors and a number of trajectories of chaotic Rucklidge system are also presented. The programming interface demonstrates the algorithm of masking and decrypt information carrier.
Enhancing of SNR and Optical Power Distribution in Indoor Visible Light Communications Systems
Get PDFThere are many difficulties that limit the applications of indoor visible light communication systems VLC such as nonuniformed power distribution, high signal to noise ratio (SNR). This paper proposed mathematical models for diffuse channel configuration and light of sight (LOS) channel configuration. All models in this paper assumed to have an arrangement of four LEDs on the room ceiling along the orthogonal axes. The paper investigates the indoor light power distribution and SNR in each layout model of LEDS . The results selected the optimized deployment in a room of 8m length, 8m width and 3 m height. The best deployment of the LOS configurations where selected to guarantee uniform received optical power distribution and acceptable SNR value. The diffuse channel configuration shows high interference rate when the sources located closed to walls
Analysis on Energy and Coverage Issues in Wireless Sensor Network
Get PDFTwo major fundamental issues in Wireless Sensor Network (WSN) are energy efficiency and coverage. Energy efficiency is the result of controlling and maintaining the energy usage. A method is considered as energy efficient if it can provide more services with the same amount of energy input, while coverage efficiency is measured by how long and how well a sensor monitors the subjected area. Hence, to obtain an energy and coverage efficiency, maximizing the coverage by reducing the energy consumption needs to be achieved. Our paper presents the potential of Derivative Harmon Search Algorithm (DHSA) in a connected WSN to achieve deployment of node that can cover optimal area and at the same time give low energy consumption
PRODUCTION OF A CONNECTING ROD OF AN 8HP DIESEL ENGINE BY REVERSE ENGINEERING TECHNIQUE USING LOST WAX CASTING METHOD
Get PDFThe aim of this work is to produce by reverse engineering method, the connecting rod of a single-cylinder, four-stroke, 8-hp diesel engine using lost wax casting and machining processes.The connecting rod to be produced was sourced from an 8hp diesel engine generator. The dimensions of the connecting rod were taken and recorded and a hand sketch of the connecting rod was made. An engineering drawing was produced from the connecting rod sketch that was made. A pattern made of wax was produced from a pattern-mould box made of ceramics. The mould that was used to cast the connecting rod was made of green sand. A replica the an 8hp diesel engine connecting rod has been produced by lot wax casting using reverse engineering method. The values obtained for engine speeds and engine temperatures for the control engine and the engine with the manufactured connecting rod were very close under the two experimental conditions, which confirmed that the efficiency of the manufactured connecting rod is close to that of the original connecting rod
A STUDY ON Y-GENERATION’S ATTITUDE TOWARDS GREEN PRODUCTS PURCHASE IN MALAYSIA
Get PDFThe green issue is being debated by communities throughout the world. Environmental issues such as air or water pollution, sound pollution, and the unexpected climate change the ozone deficiency and their unwanted effects on environment are quite well informed to individuals. This research is to identify the Y generation’s purchasing attitude of green products in Malaysia. The research background will discuss details of green products and Y generation’s definition in Malaysia. Examining the measure of consumers’ green purchase behavior would lead to a better understanding of green product acceptance and hence will lead to a more friendly environment. It has been suggested that increased awareness of environmental impacts could lead to more responsible decision purchased behavior towards green products
VIBRATION ANALYSIS OF INDIAN HUMAN SUBJECT IN SITTING POSTURE
No full textThe human body shows a non-linear and dynamic behavior under different vibration conditions that occur while travelling, walking and performing other activities.Thus, it becomes necessary to study effects on the human body that lead to different types of body pain and discomfort. In this study, an attempt has been made to find out natural frequencies and mode shapes of an Indian male subject in sitting posture without backrest using FEM approach. The results will be helpful in the designing of products for human use like automobile seats and machine parts to minimize the effect of vibrations on human body. A 3-D CAD model of human subject was generated using physical dimensions and anthropometric data available in the existing literature. A CAD model of the human body was segmented into a simple model using segments of ellipsoidal shape. As observed from this study, at 2.8 Hz maximum deformation of 56 mm occurred at head segment and with the increase in natural frequency it started diverting to lower arms. At 18.7 Hz, maximum deformation (124 mm) occurred at lower arms of human subject.Also, no deformation occurred at lower body segments below hip joint.The results obtained are in validation with the existing literature
Position Tracking Performance for ElectroHydraulic Actuator System with the Presence of Actuator Internal Leakage
Get PDFElectro-hydraulic actuator (EHA) system is known as one of the highly nonlinear systems due to its parameters uncertainties. Many types of robust controller had been studied and proposed to control the nonlinear EHA system. Different parameters uncertainties test is needed in the procedure to evaluate the controller robustness. In this paper, the effect of the actuator internal leakage to the output actuator displacement is studied. The actuator output displacement is analyzed using Root Mean Square Error (RMSE) by means of giving sinusoidal input reference. The results show that as the actuator internal leakage increases, the RMSE will increase and the actuator will start to vibrate or show damping characteristics