• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 제36회 하계학술대회 논문집 A
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• pp.350-352
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• 2005

This paper presents the results of an investigation and assessment of the direct short term impacts of electric service interruption incurred by public customers. The study used a direct visit survey to determine the customer assessment of electric service interruption and characteristic. The variation in interruption cost with the characteristics of interruptions such as duration, time of day, frequency, and day of interruption was also investigated.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2005년도 제36회 하계학술대회 논문집 A
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• pp.748-750
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• 2005

This paper approaches a methodology for deciding the optimal reliability criteria for an optimal composite power system expansion planning considering generation and transmission systems simultaneously. A probabilisticreliability criterion, $LOLE_R$(Loss of Load Expectation), is used in this study. The optimalreliability criterion $LOLE_R*$ is decided at minimum cost point of total cost curve which is the sum of the utility cost associated with construction cost and the customer outage cost associated with supply interruptions for load considering forced outage rates of elements(generators and lines) in long term forecasting. The characteristicsand effectiveness of this methodology are illustrated by the case study using MRBTS size system.

• International Journal of Knowledge Content Development & Technology
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• 제4권2호
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• pp.5-23
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• 2014

The instant messenger (IM) is frequently encountered as a facilitator of communication in both social and working contexts. Nevertheless, there are concerns about the extent to which IMs bring organizational benefits, thereby overcoming interruptions to work. In this study, we focus on how IM tools contribute to knowledge transfer at work, as well as their influence on team performance. Our research model is validated by a survey of work professionals (n=41) at a small sized company. Implications and conclusions are discussed.

• International Journal of Knowledge Content Development & Technology
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• 제4권2호
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• pp.25-47
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• 2014

The goal of the present study is to explore IM interruption by relating it to media choices and purposes of IM use in the workplace. Two major media choice concepts were: media richness and social influence; while four purposes of IM use were: organization work, knowledge work, socializing, and boundary spanning activities. Data (N = 283) were collected via a combination of convenience and snowball sampling of "computer-using workers" in Taiwan, based on the Standard Occupational Classification system published by the Taiwan government. Results indicated that media choice works better than purpose of IM use to explain IM interruption. Among them, social influence was the best predictor to IM interruption in the workplace. In addition, instant feedback and personalization provided by IM, and IM usage for the purposes of knowledge work and socializing, also relate to IM interruption in the workplace.

• Journal of Electrochemical Science and Technology
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• 제3권4호
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• pp.154-158
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• 2012

It is generally known that electrochemical impedance spectroscopy is a powerful technique and its real-time application has been demanded for prompt observations on instantaneous electrochemical changes. Nevertheless, long measurement time and laborious analysis procedures have hindered development of it. Solving the problems, here I report of a new algorithm design for development of a real-time electrochemical impedance monitoring system, which potentially provides a guideline in developing monitoring systems of electric vehicles batteries and other electrochemical power plants. The significant progress in this report is employment of the parallel processing protocol which connects independent sub functions to successfully operate with avoiding mutual interruptions. Therefore, all the processes required to monitor electrochemical impedance changes in realtime are properly operated. To realize the conceptual scheme, a Labview program was coded with sub functions units which conduct their processes individually and only data are transferred between them through the parallel pipelines. Finally, measured impedance spectra and analysis results are displayed, which are synchronized according to the time of change.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1992년도 하계학술대회 논문집 A
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• pp.51-54
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• 1992

Protection and control systems play a prominent part in avoiding power delivery interruptions and help to get a fast and secure restoration when a failure occurs. In order to meet the higher functional requirements on modern power system, protection speed, selectivity, sensitivity, dependability, and security are essential to ensure reliability. These functions on be satisfied by taking advantage of microprocessor and communication technologies, and digital protection relays (systems) have been developed and applied to real power system enhancing reliability and saving money. It is necessary to have a tool to analyze the functions and algorithms of digital relays for installing them to power system. The purpose of this study is to develop a digital relay simulation program to estimate digital relay performances during system faults. Components of digital protective relay including analog filter, sampling unit, digital filter, and relay logic are modeled in this program.

• Tuberculosis and Respiratory Diseases
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• 제75권1호
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• pp.1-8
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• 2013

Several papers on respiratory and critical care published from March 2012 to February 2013 were reviewed. From these, this study selected and summarized ten articles, in which the findings were notable, new, and interesting: effects of high-frequency oscillation ventilation on acute respiratory distress syndrome (ARDS); safety and efficacy of hydroxyethyl starch as a resuscitation fluid; long-term psychological impairments after ARDS; safety and efficacy of dexmedetomidine for sedation; B-type natriuretic peptide-guided fluid management during weaning from mechanical ventilation; adding of daily sedation interruptions to protocolized sedations for mechanical ventilation; unassisted tracheostomy collar of weaning from prolonged mechanical ventilations; and effects of nighttime intensivist staffing on the hospital mortality rates.

• ETRI Journal
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• 제34권5호
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• pp.771-774
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• 2012

Typical channel allocation algorithms for secondary users do not include processes to reduce the frequency of switching from one channel to another caused by random interruptions by primary users, which results in high packet drops and delays. In this letter, with the purpose of decreasing the number of switches made between channels, we propose a nonparametric channel allocation algorithm that uses robust kernel density estimation to effectively schedule idle channel resources. Experiment and simulation results demonstrate that the proposed algorithm outperforms both random and parametric channel allocation algorithms in terms of throughput and packet drops.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2003년도 추계학술대회 논문집
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• pp.202-205
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• 2003

Recently, UPS(Uninterruptible Power Supply) have been largely used to improve power souse quality as well as to protect critical loads such as computer, industrial system, medical equipment, etc, against power outage by providing clean and uninterrupted power under power supply disturbance or interruptions. But UPS is bulky because used battery. So, UPS size issue have received attention in the power electronics industry. Therefore, this paper proposed a implementation of inside of the computer power supply with UPS by the one-chip microprocessor to minimize UPS size. To verify the proposed power supply, the detail simulation and experiment results indicate that high-frequency switching and operation UPS can be achieved.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 추계학술대회 논문집 전력기술부문
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• pp.9-14
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• 2002

In front of the opening of electric distribution market in 2004. it is indispensable to have a proper estimation of power quality index and power quality cost calculation mechanism are indispensable to stabilize highly industrialized society and to vitalize the investment for electric power system. However, there were not enough measures to reflect the voltage characteristics such as voltage sags and interruptions which make electric load in unstable operation. This paper suggests power quality index(LDI) and power quality cost(LDC) which translate various kinds of voltage records into load drop index and cost based on aggregated load CBEMA curve. A sample calculation result shows that this method can produces the acceptable power quality index and costs for utilities and customers requirements.