Universiti Teknikal Malaysia Melaka: UTeM Open Journal System
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Power Quality Issue of Grid Connected DFIG Wind Farm System
Get PDFQuality of power is known as any power problem manifested as a non-standard frequency, current and voltage which cause failure of end customer apparatus. The wind utilization, generation and its penetration in utility grid are increasing worldwide. One of the master issues in wind generation is the insertion to the network. When the wind energy is injected to the grid generally controls the voltage disturbances on the system power quality, variation of voltage is the almost prevalent kind of disturbance which affects stability and the quality of power for grid-inserted wind system. This study investigates the two widespread kinds of voltage variations such as voltage dip and swell, which can happen if large amount of wind system is connected to an electrical grid. This research also studies the response and performance under faults of a wind farm inserted to distribution systems. In this paper, a wind turbine with induction machine (DFIG) is simulated by using MATLAB/Simulink program. The simulated model is subjected to disturbances which known as; voltages (dip and rise). The results of simulation presents that, how both variations; voltage dip & voltage rise lead to mal-operation as well as shut-down of entire system, therefore deteriorating the improvement of power quality for the grid
Experimental and CFD studies of a thermoacoustic apparatus
Get PDFThis paper reports a study of a thermoacoustic system by both experimentation and simulation. A small scale thermoacoustic refrigerator prototype was built for experimentation purposes. In addition, a two-dimensional transient thermoacoustic model was solved by using computational fluid dynamics (CFD) software. In experimentation, a small thermoacoustic refrigerator (TAR) rig operated at a frequency of 133.45 Hz was built and the system was tested using two different types of stack; acrylonitrile butadiene styrene (ABS) and a stainless-steel scrubber. At atmospheric pressure and a relatively low frequency, a small temperature drop is recorded. Similar result was obtained using a simple CFD model that was designed based on the actual operating parameters of the experimental rig with ABS as a stack. The study shows that thermoacoustic principles can be used as a sustainable and green alternative technology for a refrigerator
HEALTHY LIFESTYLE INSTRUMENT
Get PDFThe main purpose of this study was to develop an instrument to measure the Healthy Lifestyle among employees of KPTM Ipoh, KPTM Alor Setar, UniSHAMS and Intel Kulim. The sample was collected using self-administered questionnaire from 16 people for our focus group based on our sampling frame design and distributed four instruments for each strata group. The total instrument from the pilot study are 64 instruments. Three (3) constructs of the Healthy Lifestyle Instrument primarily consist of Fitness Wellness, Dietary Wellness and Behavior Wellness. The result of descriptive analysis show that the alpha reliability of the construct items in healthy lifestyle are acceptable. This would be express that the Healthy Lifestyle Instrument be considered reliable. However, in the exploratory factor analysis show that the findings are expanded from three factors to seven factors of employee healthy lifestyle practices. As related to this and previous analysis, we conclude that the Healthy Lifestyle Instrument are valid and reliable. However, this will require full data collection in order to fully validate the instrument. Therefore, the 3 aspects of employee’s healthy lifestyle practices will remain the same as before the test performed. This is due to small sample size in pilot study. The same analysis procedure will be performed using sufficient sample size. However, in term of factor analysis in the main study, the finding of new emerge factors from the previous pilot study will be executed in order to conclude the final factoring involve. Keywords: health, lifestyles, exploratory factor analysi
EXPLORATORY DATA ANALYSIS ON HOUSEHOLD EXPENDITURE SURVEY 1998 AND 2014
Get PDFHousehold Expenditure Survey (HES) was utilized to accumulate information on the level and patterns of consumption expenditure of private households. It was additionally used to update the weighting patterns and to decide the items in the basket of goods and services for the compilation of the Consumer Price Index for Malaysia. The primary goals of HES are to assemble information on the level and pattern of consumption expenditure by household on a comprehensive range of goods and services. It additionally to decide the goods and services to be included into the basket of the Consumer Price Index (CPI) and to update the CPI weights which is a proportion of expansion rate in the country. Hence, this study is conducted based on HES information gathered on 1998 and 2014. The objectives of this study are to implement Exploratory Data Analysis (EDA) approach on HES data for the year 1998 and 2014 and to define who is the good spender and the bad spender is based on their income and expenditure. Keywords: Household Expenditure Survey (HES), Exploratory Data Analysis (EDA), expenditure, incom
Conceptual Design Of Cargo Airplane
Get PDFThe main goal of the work is to design the military cargo aircraft that fulfils all the requirements. Current work includes weight estimation of an aircraft, selection of airfoil and suitable wing configuration, selection of tail, fuselage sizing and power plant selection. From the available details, weight estimation of the aircraft was started, by assuming the soldiers weight and baggage allowance, with the available empirical relations, weight estimation was done. There are many conditions to select feasible airfoil for the aircraft, with the consideration of design Mach number and design lift coefficient airfoil was selected, then for aircraft flight regime, suitable wing configurations was selected. Primary objective of fuselage is to accommodate the soldiers, crew members in cockpit, and cargo, to place all these in the fuselage, space was sized and proper aisle was given in between with reference to the military standards. Need of Empennage is to provide the stability for aircraft, by checking the required stability for aircraft, horizontal and vertical tail was sized and suitable configuration was selected from the historical trends and requirement. In the design stage feasible engine for the aircraft was selected
The Development of an Automated Irrigation System Using an Open Source Microcontroller
Get PDFThis paper proposes an automated irrigation using Arduino microcontroller system which is cost effective and can be used in a farm or average home garden. The proposed system is developed to automatically water the plants when the soil moisture sensor has detected the soil is insufficient of water by using the Arduino as the center core. The automated irrigation system is a fully functional prototype which consists of a soil moisture sensor; an LCD display to show the moisture percentage and pump status; a relay module which is used to control the on and off switch of the water pump; and a water pump. When the soil moisture sensor senses the dry soil, it will show the moisture percentage on the LCD display, and the relay module will switch on the water pump automatically to start the watering process or vice versa. Hardware testing is conducted to ensure the proposed system is fully functional
A Study on Low Cost Microcontrollers for Converter Applications
Get PDFIn this project, the development of a control system based on single phase inverter in hardware and simulation have been conducted to study the use of low-cost microcontroller for converter application. Therefore, this project aims to develop a voltage control system that can be designed in Raspberry Pi and Arduino to understand the effectiveness of the microcontrollers. The inverter voltage is being controlled using Pulse Width Modulation (PWM) that is modelled using a feedback control using the MATLAB Simulink as a code generation. At the meantime, the Proportional (P) control has been used for the inverter output control in order the output voltage to follow the target reference value. This study has been divided into two stages where the MATLAB simulation has been developed for determined the control response for the single-phase inverter when using the Raspberry PI and Arduino as the source generation. After it has been successfully designing deed, the hardware has been set up to see the operation of the inverter with the voltage control that has been built in the MATLAB, by connecting to a resistive load as to represent any household applications such as a fluorescent lamp. The results show that, by using these low-cost microcontrollers, the controller is more accessible to be developed in the MATLAB and able to respond well to the hardware
UNIVERSAL DESIGN METHOD THAT CONSIDERS PHYSICAL BURDEN THROUGH THE APPLICATION OF A DIGITAL HUMAN MODEL: CASE STUDY OF A WORKING TABLE
Get PDFRecently, owing to aging and internationalization, the concept of universal design aimed at satisfying various users has attracted attention. However, the concept and definition of universal design varies between countries or companies, and a general approach to such design has yet to be established. Moreover, it is not clear how to take users’ physical characteristics and feelings when using a product into consideration. Therefore, in this research, the authors propose a universal design method that considers the user's physical burden by applying a digital human model. First, the authors divide design variables into designer-controllable and uncontrollable factors. Next, based on the human characteristics database, design variables and constraint conditions are defined as range values. Then, an interval operation is performed using aforementioned ranged value and a relational expression between a design variable and a constraint condition, and a design solution is derived as a set. Furthermore, based on the derived design solution sets, the authors simulate use of a product by a digital human model. Finally, by evaluating physical load, the authors derive a design solution that takes account of the user's physical burden, using a working table as a case study
Performance of Yaskawa Motoman Industrial Robot under Loaded Conditions and Various Distances
Get PDFIntroducing robotics into the manufacturing process brings benefits such as an increase in productivity, cost reduction and waste minimization. Robotic equipment is highly accurate with repeatability capability to perform various works. It is important for robot users to know the robot’s current performance compared to its technical specification to ensure its suitability for the current task. Yaskawa Motoman MH5F is an industrial robot commonly used in material handling application. The aim of this project is to investigate the accuracy and repeatability of this robot for different payload and various distances using laser interferometry method. An interferometer is a clear-cut instrument designed to measure objects accurately. Laser interferometry uses the interference method of two or more waves for the purpose of recognizing contrasts between them. There were 12 sets of experiments conducted. For each set of load and distance, the experiment was repeated for 30 times. Results show that the robot repeatability and accuracy value obtained are ±0.0047 mm and ±0.237 mm respectively. Hence, this proved that Yaskawa Motoman MH5F robot has better repeatability compared to the robot’s technical specification, which is ±0.02 mm. Regression analysis carried out using Microsoft Excel displayed the only repeatability against distance factor showing positive linear correlation. For further improvement, this experiment can be carried out with various weight and different distances to identify the machine’s maximum capability