1,548 research outputs found

    Investigating the use of the e-mail in the teaching and learning of a technical subject among Polytechnic Ungku Omar Students

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    Through the use of technology in education, effectiveness in the teaching and learning process can be achieved. In this project, the researcher wants to identify whether the usage of the electronic mail in the teaching and learning of a technical subject will benefit the teaching and learning process or not. Other than that, researcher wants to identify problems faced in applying the electronic mail in the teaching and learning of a technical subject among Polytechnic Ungku Omar students. Respondents of the project were one class of Polytechnic Ungku Omar students who were taking Data Communication subject. There were two research approaches used in getting the data which are qualitative approaches and quantitative approach. Qualitative data includes data collected through observations, interview and content analysis. Quantitative data includes data collected through questionnaires. Data collected reveals that participants used the e-mail in different ways which brought them various benefits. E-mail was used as a pedagogy of teaching and learning, medium of communication and tool for different purposes like academic purposes, general query and query for personal development, socializing, complaining and suggesting ideas. The use of e-mail was influenced by factors like gender, personality, experience in using e-mail and the features of the e-mail itself. However, the problem faced by the students such as slow downloading or server problems, limited number of computers for use, limited number of computer labs, many of the computers in the polytechnic were not working properly, crowded computer lab, compact personal time table, lecturer to students ratio was too high, difficult to understand the description, do not have enough money to surf at Cyber Cafe and no free or confirmed access to Internet in Polytechnic have influenced the use of the electronic mail in the teaching and learning of a technical subject among Polytechnic Ungku Omar student

    Analysis and design of high-transconductance RF mosfet voltage to-current converters

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    The research described in this thesis is concerned with analysis and design of "HighTransconductance RF MOSFET Voltage-to-Current (V-I) Converters". Various V-I converter circuits published in the past have been reviewed by the author in order to understand the different techniques employed to improve transconductance (Gt), linear operating range and total harmonic distortion (THO). Throughout this research, the emphasis has been to improve the above mentioned parameters. All the V-I converter circuits reported have been simulated using PSPICE and the results compared with the values obtained by theoretical analysis. Some of the results of this work have been already reported by the author in the technical literature. (See Chapter 9, at the end of this thesis, where reference to two publications by the author is given.) It was essential to obtain accurate CMOS device parameters values, such as Early Voltage, transconductance parameter ratios!! (gm/gds), X (gmbl'gm) and inter-electrode capacitances, to facilitate the design the prQcess. This was achieved using an extensive set of simulations for the transistor operating under different bias conditions. Furthermore, a measurement technique, thought to be novel, for the direct determination of the transconductance ratios!! and X is proposed. In the next part of the work several types of current mirror are compared against the standard current mirrors, using analytical and simulation methods. Furthermore several MOSFET V-I converter designs were critically reviewed to understand the various existing techniques and their limitations. Two novel techniques, Drain-Source Feedback Circuits (DSFCs) and Drain-Gate Feedback Circuits (OGFCs) ere implemented with a new temperature-compensation scheme, designed to operate well in an industrial environment (-40°C - +8S°C). It is found that the best types of V -I converters were the DSFCs which, offer a more accurate value of Gt (3.386mS) and the THO less than -S7dB for a differential input operating range SOOm V at 1 GHz with a 3V total rail voltage. The OGFC circuits were also meet the initial design targets, the value of THO is less then -SOdB, and operating in the Giga hertz frequency range is possible. Preliminary investigation on future work shows promising results

    Improved Variable Neighbourhood Descent (VND) to Solve Universiti Malaysia Sarawak (UNIMAS) Course Timetabling Problem

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    Academic institutions face the timetabling problem every semester. The task of allocating lectures to limited timeslots and venues must fulfil certain constraints unique to each educational institution. This study investigated heuristic orderings and the variable neighbourhood descent approach to tackle the course timetabling problem at the Faculty of Computer Science and Information Technology (FCSIT), Universiti Malaysia Sarawak (UNIMAS) on the basis of the students. The objectives of the study were to formulate a mathematical model and improve a computational bounded heuristics-based solution to solve the course timetabling problem at the faculty. A two-stage heuristic algorithm is proposed. In stage 1, heuristic orderings were utilised to find a feasible solution using 31 timeslots instead of the 48 timeslots in the existing timetabling software. In stage 2, the variable neighbourhood descent approach with new neighbourhood structures was utilised to improve the quality of the solution. The improved algorithm was tested on real-world data instances (in semesters 1 and 2 of 2019/2020) at the FCSIT, UNIMAS. The results show that certain heuristic orderings (the largest degree or the combination of the largest degree and largest enrolment in descending order) are better than others in generating a feasible solution. In stage 2, the proposed algorithm with new neighbourhood structures managed to reduce the soft constraint violations for instances in semesters 1 and 2. Sensitivity analysis was performed on the proposed algorithm. The experimental results demonstrate the flexibility of the proposed algorithm in solving the university course timetabling problem (UCTTP) at the FCSIT

    An Empirical Classification of Bidders in Online Auctions

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    Auctions have been a popular way of transaction on the Internet. Most of the studies of auction assume participants attending the auction are homogeneous. However, this assumption is open to question. In fact, every participant has his own personality, risk attitude, behavior, and cost when attending online auctions. This study takes an empirical approach and uses four variables, time of entry, time of exit, number of bids, and number of jump bids, to find the heterogeneity among bidders. We first used k-means clustering method to identify the types of bidders of online auctions, and then used C5.0 decision tree learning algorithm to find the rules to differentiate bidders. A taxonomy of four types of bidders is proposed in the study, which include observers, adventurers, opportunists, and early players. The results also suggest pacing of the auctions is an important factor that will affect bidder’s behavior in online auctions

    IJEPA: Gray Area for Health Policy and International Nurse Migration

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    Indonesia is recognized as a nurse exporting country, with policies that encourage nursing professionals to emigrate abroad. This includes the country's adoption of international principles attempting to protect Indonesian nurses that emigrate as well as the country's own participation in a bilateral trade and investment agreement, known as the Indonesia�Japan Economic Partnership Agreement that facilitates Indonesian nurse migration to Japan. Despite the potential trade and employment benefits from sending nurses abroad under the Indonesia�Japan Economic Partnership Agreement, Indonesia itself is suffering from a crisis in nursing capacity and ensuring adequate healthcare access for its own populations. This represents a distinct challenge for Indonesia in appropriately balancing domestic health workforce needs, employment, and training opportunities for Indonesian nurses, and the need to acknowledge the rights of nurses to freely migrate abroad. Hence, this article reviews the complex operational and ethical issues associated with Indonesian health worker migration under the Indonesia�Japan Economic Partnership Agreement. It also introduces a policy proposal to improve performance of the Indonesia�Japan Economic Partnership Agreement and better align it with international principles focused on equitable health worker migration

    Sources and Losses of Ring Current Ions

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    During geomagnetic quiet times, in-situ measurements of ring current energetic ions (few to few tens of keVs) from THEMIS spacecraft often exhibit multiple ion populations at discrete energies that extend from the inner magnetosphere to the magnetopause at dayside or plasma sheet at nightside. During geomagnetic storm times, the levels of fluxes as well as the mean energies of these ions elevated dramatically and the more smooth distributions in energies and distances during quiet times are disrupted into clusters of ion populations with more confined spatial extends. This reveals local plasma heating processes that might have come into play. Several processes have been proposed. Magnetotail dipolarization, sudden enhancement of field-aligned current, local current disruptions, and plasma waves are possible mechanisms to heat the ions locally as well as strong convections of energetic ions directly from the magnetotail due to reconnections. We will examine two geomagnetic storms on October 11, 2008 and July 22, 2009 to reveal possible heating mechanisms. We will analyze in-situ plasma and magnetic field measurements from THEMIS, GOES, and DMSP for the events to study the ion pitch angle distributions and magnetic field perturbations in the auroral ionosphere and inner magnetosphere where the plasma heating processes occur

    From Teachers’ Views to Explore the Implementation of Energy Education in Taiwan’s Elementary Schools

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    This study intended to explore the implementation of promoting “energy education” in Taiwan’s elementary schools. The research adopted a questionnaire (Likert five-point scale) from teachers’ view in three dimensions to construct examination. The 45 participants come from 10 different primary schools distributed across Taiwan, which participate in energy education program in the second period (2015-2017). The data was analyzed by ANOVA, mean and standard deviations of the viewpoints of the participants in the energy education learning achievement of the primary schools. The first findings in this research is, the program of energy education was most effective in “energy attitude” (M=4.282, SD=0.814), followed by “energy awareness” (M=4.049, SD=0.720) and “energy behavior” (M=3.983, SD=0.875). It shows that students have positive energy attitude, but they were relatively weak at energy saving behavior. Secondly, there is statistically significant difference in overall students learning performance with urban areas are higher than rural areas. Finally, it is suggested that in addition to strengthen energy attitudes and energy awareness, we should encourage students to take action in save energy in their daily life. Furthermore, we should invest more resources to rural areas to balance the students’ performances between urban and rural areas

    Modeling of the Convection and Interaction of Ring Current, Plasmaspheric and Plasma Sheet Plasmas in the Inner Magnetosphere

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    Distinctive sources of ions reside in the plasmasphere, plasmasheet, and ring current regions at discrete energies constitute the major plasma populations in the inner/middle magnetosphere. They contribute to the electrodynamics of the ionosphere-magnetosphere system as important carriers of the global current system, in triggering; geomagnetic storm and substorms, as well as critical components of plasma instabilities such as reconnection and Kelvin-Helmholtz instability at the magnetospheric boundaries. Our preliminary analysis of in-situ measurements shoves the complexity of the plasmas pitch angle distributions at particularly the cold and warm plasmas, vary dramatically at different local times and radial distances from the Earth in response to changes in solar wind condition and Dst index. Using an MHD-ring current coupled code, we model the convection and interaction of cold, warm and energetic ions of plasmaspheric, plasmasheet, and ring current origins in the inner magnetosphere. We compare our simulation results with in-situ and remotely sensed measurements from recent instrumentation on Geotail, Cluster, THEMIS, and TWINS spacecraft

    Ixora parviflora Protects against UVB-Induced Photoaging by Inhibiting the Expression of MMPs, MAP Kinases, and COX-2 and by Promoting Type I Procollagen Synthesis

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    Ixora parviflora with high polyphenol content exhibited antioxidant activity and reducing UVB-induced intracellular reactive oxygen species production. In this study, results of the photoaging screening experiments revealed that IPE at 1000 μg/mL reduced the activity of bacterial collagenase by 92.7 ± 4.2% and reduced the activity of elastase by 32.6 ± 1.4%. Therefore, we investigated the mechanisms by which IPE exerts its anti-photoaging activity. IPE at 1 μg/mL led to an increase in type I procollagen expression and increased total collagen synthesis in fibroblasts at 5 μg/mL. We found that IPE inhibited MMP-1, MMP-3, and MMP-9 expression at doses of 1, 5, and 10 μg/mL, respectively, in fibroblasts exposed to UV irradiation (40 mJ/cm2). Gelatin zymography assay showed that IPE at 50 μg/mL inhibited MMP-9 secretion/activity in cultured fibroblasts after UVB exposure. In addition, IPE inhibited the phosphorylation of p38, ERK, and JNK induced by UVB. Furthermore, IPE inhibited the UVB-induced expression of Smad7. In addition, IPE at 1 μg/mL inhibited NO production and COX-2 expression in UV-exposed fibroblasts. These findings show that IPE exhibits anti-inflammatory and anti-photoaging activities, indicating that IPE could be a potential anti-aging agent
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