525 research outputs found

    AC Breakdown Characteristics of LDPE in the Presence of Crosslinking By-products.

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    LDPE films of 50?m thick were soaked into crosslinking byproducts which are acetophenone, ?-methylstyrene and cumyl alcohol. The samples were used to perform the breakdown strength (Eb) of the LDPE with the byproducts chemical reside in the sample. The AC breakdown measurements were conducted at a ramp rate of 50V/s at room temperature. Weibull plot is used to analyse the ac breakdown result. Comparing the soaked and un-soaked (fresh LDPE) samples, it does show a small reduction of the eta values as the LDPE films were soaked into the sample. It suggests that the breakdown strength is reduced by adding the byproducts in the LDPE film. However, as the range of breakdown strength of all samples are to be compared, these values fall in the same region which indicate no significant difference can be seen in all samples

    Quality-based Spatial/Spectral Image Transformation

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    Remote sensing image plays a very important role for GIS services as one of its important data source. It’s very large volume requirement may lead to latency during data transmission. Several alternative solutions are identified as the solution for the issue. This paper is intended to discuss the effect of image compression technique to allow the reduction of the storage and bandwidth requirement at the same time maintaining the quality of the compressed image. An experiment has been performed towards several multispectral images to foresee the effectiveness of the proposed method. The ongoing study shows promising result especially in terms of storage and image quality

    Experiment study of using parallel plate sensor for the detection of conductive material

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    Gold is the yellow precious metal that has been used in many applications likes medicine, electronics, jewelry, investment and others. Thus, gold is one of the commodities which has high demand in the global market. In other to secure the purity of gold and to protect the retailer and consumer from fraud, the detection of gold is very important in the industry. There are many techniques have been used to detect the purity of gold material and those techniques must consider a several factors such as non-destructive, inexpensive, precise, simple and widely accepted by the jewelry industries. Electrical capacitance tomography (ECT) is the most mature non-destructive technique among various tomography. The advantages of ECT are non-radioactive, non-intrusive, high imaging speed and low cost. This paper introduces the ECT using the square sensor. The aim of his paper this to present a new method of verifying the conductive materials using a parallel plate sensor which adopted from the ECT system

    Designing Problem Based Learning (PBL) Problem Scenario for Statistic Using Linear and Non-linear Multimedia Presentation

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    Problem Based Learning (PBL) is an instructional method that is known to offer students with knowledge suitable for problem solving. In order to test this assertion the process of problem based learning is described and measured against three principle of learning: activation of prior knowledge, elaboration and encoding specificity. Using PBL method, students’ understanding with regards to the problem scenario is very significant process. One of the main defining characteristic of PBL, which distinguishes it from some other method, is that the problem is presented to the students first at the start learning process. Traditionally, problem scenario is presented in a printed text, which is not tempting for student to understand the motive behind it. Information and Communication Technology (ICT) on the other hand has widely accepted in many areas which include education as well. By applying multimedia presentation as a discipline in ICT, it is believed that it could helps in designing the effective problem scenario. The purpose of this study is to design and test the effectiveness of PBL problem scenario for subject Statistic using linear and non-linear multimedia presentation. Linear presentation is known as no navigation control is involved through that process while nonlinear presentation uses user interactivity to control the presentation. This paper discusses the early storyboard design and the icons that used

    DEVELOPMENT OF RESEARCH FRAMEWORK FOR PBL PROBLEM SCENARIO USING LINEAR & NON-LINEAR MULTIMEDIA

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    Problem Based Learning (PBL) is an instructional approach to provide student with knowledge suitable for problem solving. To support the research, PBLStat courseware is developed based on the PBL approach. In PBL approach, problem scenario is first presented during the learning process. Problem scenario helps to maintain student interest in course so it is important to create a good problem that can cause students‘ inquiry and drive students to solve the problems. The purpose of this paper is to highlight the development of research framework for PBL problem scenario presentation. Problem scenario can be presented using linear and non-linear multimedia categories. The framework of study contains the description of research control modes, content and output. The control modes of the research are consisting of two independent variables which are linear problem scenario and non-linear problem scenario. Content is the phase of courseware‘s development. The ADDIE model is used to complete the development of courseware. Finally is the research output, this is to evaluate student‘s preferences and performances based on the problem scenario categorization. There are four research instrument tools has been created to answer the research question which are questionnaire, observation, interview and PBLStat

    Optical properties of diamond like carbon films prepared by DC-PECVD

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    Diamond-like carbon (DLC) thin films were deposited at different substrate temperatures using methane and hydrogen gas in DC-PECVD at 2x10-1Torr. From the light transmission using UV-VIS spectroscopy it was found that the optical transition had changed from allowed indirect transition to allowed direct transition as the substrate temperature increased. The Optical gap increased with temperature, highest of 3.034 eV was observed at 573 K, beyond which it dropped. Colour of the film changed from light brownish to a colourless transparent film in the higher temperature. The Urbach energy decreased from 1.25 eV to 0.75 eV with increasing substrate temperature till 573 K and a slight increase after it. This trend is attributed to change in sp3/sp2 ratio or change in structure. The cluster size decreases with temperature, resulting in larger band gap and the structure more ordered. Similar pattern is also witnessed in the emission spectrum of the photoluminescence

    High Voltage Durability of Bambusa Vulgaris as a Bio-composite Material

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    This study is conducted in order to measure and identify the ability of a bio-composite material to the high voltage. According to it, the developed bio-composite material is tested to ensure the maximum voltage that the material can hold. The bio-composite material which made from a mixture of Bambusa Vulgaris and a selected polymer named as High Density Polyethylene (HDPE). The Bambusa Vulgarisis going through several processes before mixed together with HDPE using wood plastic composite (WPC) technique which also consists of several stages. There are several samples of bio-composite substance are fabricated. The difference among them is the composition of the raw materials (Bambusa Vulgaris and HDPE) used. In this research, the high voltage measurement which also called as breakdown voltage measurement of the bio-composite material is examined by using appropriate experiments. All the experimental results are presented and discussed in this paper

    Study of underfill flow in microchip packaging using ansys

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    The project was related to microchip application where adhesive fluid is used to stick the microchip onto the electrical flat base. In this project, 5mm of width and length of microchip with 3 different types of solder ball diameter sizes are used in this project. The objective of the project is to study the flow pattern and velocity of fluid during injection based on the decided parameters, which are initial velocity, fluid viscosity, and the diameter of the solder ball. Each parameter that has been set produces a different outcome in terms of flow pattern and velocity of fluid. To maximise the performance of fluid flow in the aspect of uniformity of the fluid flow to fill the gap around the solder ball, the flow pattern and the velocity are being observed and recorded throughout the simulation process

    Customized physical and structural features of phosphate-based glass-ceramics: role of ag nanoparticles and ho3+ impurities

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    The effects of silver nanoparticles (Ag NPs) embedment on the physical and structural characteristics of the holmium ions (Ho3+) activated phosphate-based glass-ceramics were assessed. Two series of such glass-ceramics were prepared using the melt-quenching and characterized. In the first series, the Ag NPs were nucleated from the incorporated AgCl via the redox process. In the second series, the pure Ag nanopowder was directly added. The overall properties of these glass-ceramics were strongly sensitive to the cooling procedure and NPs addition strategies, leading to different density and refractive index modifications in the two series. The recorded O1s XPS peaks were exploited to determine the bridging to non-bridging oxygen ratios in the studied glass-ceramics network that enabled to unfold the differences in the observed inferences. A compelling correlation among various attributes in the achieved glass-ceramics was established. Briefly, the overall traits of the proposed glass-ceramics were tailored by regulating the preparation conditions
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