Saeed Vahabi Mashak

Simulation of Lightning Flash in Time of Arrival (TOA) Method by Using Three Broadband Antennas

Various methods are used to locate cloud-to-ground lightning flash. The accuracy of the methods depends on the number of sensor stations, station topology, mathematical model adopted for the analyses, and type of measuring equipment. For a single station with the configuration of short baseline in a measuring system, the accuracy analysis is mostly based on the chosen mathematical equations (and all relative assumptions) which can be solved in either linear or nonlinear mode. This paper concentrates on the simulation of a lightning flash based on Time of Arrival (TOA) method by utilizing three broadband antennas. The accuracy of the TOA method is also evaluated in this work. A Mat lab based simulation of the measuring system is implemented to construct a randomly located lightning flash with its corresponding electromagnetic radiation. Then, suitable mathematical models used as measurement systems based on the TOA method to determine the azimuth and elevation angles.

Economic Sizing of Solar Array for a Photovoltaic Building in Malaysia with Matlab

This article illustrates a simulation method to find a sizing and economic of a required photovoltaic array for a photovoltaic building in Malaysia. This paper represents the result using by Matlab software and also mathematic equation. It is known that the important factor for photovoltaic system is cost of a system, and because of several kinds of the photovoltaic array we have the right to select the best array with the best efficiency and best price. The popular types of materials are crystalline and thin films, which have differences in terms of light absorption efficiency, energy conversion efficiency, manufacturing technology and cost of production. Different kinds of crystalline materials like a mono-crystalline, polycrystalline are available. In this paper, the generated current and generated power by the photovoltaic array is calculated according to daily solar irradiation when the case study is Malaysia. Think over generated power of each arrays and also according to required energy for a typically building, the number of photovoltaic array is estimated then the cost of the solar array is calculated. System is simulated by Matlab software, and the results are discussed. The simulation is about sizing and economic in order to select the best array for photovoltaic system to have a optimize system according to size and price of the system.

Background subtraction for object detection under varying environments

Background subtraction is widely used for extracting unusual motion of object of interest in video images. In this paper, we propose a fast and flexible approach of object detection based on an adaptive background subtraction technique that also effectively eliminates shadows based on color constancy principle in RGB color space. This approach can be used for both outdoor and indoor environments. Our proposed method of background subtraction makes use of multiple thresholding technique for detecting object of interests for any given scene. Once the moving object has been detected from the complex background, then the shadows are detected and eliminated by considering some environmental parameters.

Automatic Segmentation of Abdominal Aortic Aneurysm Using Logical Algorithm

Abdominal aortic aneurysm is a cardiovascular disease which occurs due to an abnormal weakening of the aorta wall. This failure in aortic wall causes the inner layer to be ruptured because of excessive blood pressure. Consequently, the blood flows into the space between lumen and epithelial, hence a thrombus is generated. On the other hand, excessive growth in the aorta diameter can lead to death as a result of a rupture in the epithelial. In this paper, we present a technique for automatic segmentation of abdominal aortic aneurysm. The proposed method integrates the exclusive information extracted from histogram and morphological properties of aortic lumen to segment the aorta. Then the proposed algorithm utilizes a search technique with priori information about the lumen to segment epithelial area automatically.

Simulation of Lightning Flash and Detection Using Time of Arrival Method Based on Four Broadband Antennas

Various methods are used to locate cloud-to ground lightning flash. The accuracy of the methods depends on the number of sensor stations, station topology, mathematical model adopted for the analyses, and the type of measuring equipment. For a single station with the configuration of short baseline in a measuring system, the accuracy of analysis is mostly based on the chosen mathematical equations (and assumptions) which can be solved in either linear or nonlinear mode. This paper concentrates on the simulation of a lightning flash and its detection based on the Time of Arrival (TOA) method by utilizing four broadband antennas. The accuracy of the TOA method is also evaluated in this work. A Matlab based simulation of the measuring system is implemented to construct a randomly located lightning flash with its corresponding electromagnetic radiation. Then, suitable mathematical models used as measurement systems based on the 3-antenna TOA method to determine the azimuth and elevation angles, which in turn can be used for the calculation of flash coordinates in term of (X, Y, Z) with the help of the fourth antenna.

Categorization of Human Movement Based on Rule-Based Classifier

Human activity recognition is an active research field in computer vision and image processing. This paper has been concentrated on the recognition between different cyclic motion activities such as running and walking. The proposed system consists of three major steps. Initially by using a single camera, in a variety of angles, the movement of the object is detected, and object silhouette is generated in each frame. Then, our proposed method for generating a skeleton of silhouette is presented. The skeleton is used to determine human activities such as running and walking. In the last stage, a rule-based classifier is used to classify the action.

Three-Dimensional Potential and Electric Field Distributions in HV Cable Insulation Containing Multiple Cavities

Cross-linked polyethylene is widely used as electrical insulation because of its excellent electrical properties such as low dielectric constant, low dielectric loss and also due to its excellent chemical resistance and mechanical flexibility. Nevertheless, the most important reason for failure of high voltage equipment is due to its insulation failure. The electrical properties of an insulator are affected by the presence of cavities within the insulating material, in particular with regard to the electric field and potential distributions. In this paper, the electric field and potential distributions in high voltage cables containing single and multiple cavities are studied. Three different insulating media, namely PE, XLPE, and PVC was modeled. COMSOL software which utilises the finite element method (FEM) was used to carry out the simulation. An 11kV underground cable was modeled in 3D for better observation and analyses of the generated voltage and field distributions. The results show that the electric field is affected by the presence of cavities in the insulation. Furthermore, the field strength and uniformity are also affected by whether cavities are radially or axially aligned, as well as the type of the insulating solid. The effect of insulator type due the presence of cavities was seen most prevalent in PVC followed by PE and then XLPE.

Implementation of Wireless Thermal Camera Remote Control System

Thermographic inspection is a very safe and non-invasive monitoring technique, widely used in electrical substations and other power plants. A thermal image can be obtained to help in identifying abnormal heating regions in power equipment. Under high voltage circumstances, it is a hazard for personals to capture the image at a close distance from the power equipment. This paper described the development of a remote control monitoring system for a thermal camera. XBEE is a new and popular protocol for wireless communication because of its low power assumption, large network capability and the ability to organize a network automatically. 10 samples data are collected within the 30m and the successful transfer rate reached 98.89%. Remote control of thermal camera helps human keep distance from the high electric field and at the same time convenient for a user to conduct online condition monitoring in order to prevent any accident in power station.