• 대한전기학회논문지:전력기술부문A
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• 제48권6호
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• pp.719-727
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• 1999

A robust position control method of the BLDC motor using a new sliding mode control strategy is presented. The main property of variable structure system(VSS) is that the system response is robust and insensitive to parameter variations and external disturbances in the sliding mode. When using the conventional VSS, generally the reaching phase problem occurs, which cause the system response to be sensitive to parameter variations and external disturbances. Furthermore, the speed of response is relatively slow because the swithching surface is a linear function. In order to overcome these problems, VSS with nonlinear sliding surface eliminating reaching phase is proposed. The validity of the proposed scheme is shown by results of simulations of simulations and experiments for the BLDC motor with variable load.

• 한국전자파학회지:전자파기술
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• 제14권1호
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• pp.35-42
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• 2003

Differential signaling has become a popular choice for high-speed interconnection schemes on Printed Circuit Boards (PCBs), offering superior immunity to external noise. However, conventional differential transmission lines on PCBs have problems, such as crosstalk and radiated emission. To overcome these, we propose a Twisted Differential Line (TDL) structure on a multi-layer PCB. Its improved immunity to crosstalk noise and the reduced radiated emission has been successfully demonstrated by measurement. The proposed structure is proven to transmit 3 Gbps digital signals with a clear eye-pattern. Furthermore, it is subject to much less crosstalk noise and achieves a 13 dB suppression of radiated emission. Index Terms - Twisted Differential Line, Differential Signaling, Crosstalk, Radiated Emission, Transmission Line, Twisted Pair

• 한국응급구조학회지
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• 제8권1호
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• pp.127-139
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• 2004

This study aims to examine the relative importance of various tasks of EMT and to examine knowledge level and problems associated with AED. It is based on the survey of paramedics and 119 rescures. The results for this study were as follows ; Among the tasks of EMT, 'foreignbody removal from mouth' were rated as the most important, followed by '$O_2$ supply', 'CPR', 'Intubation for CPR', '$O_2$ supply' were rates as the most necessary, followed by 'foreignbody removal from mouth', 'external bleeding control'. In terms of the knowledge level about AED, survey respondents are most knowledgeable about 'role of other rescures during the preparation for AED' and 'treatment after 3 AEDS. The most important reason that the uses of AED is delayed is 'unclear boundary of treatment directed by medical control'. The results of the study suggest that we need guideline for EMT's tasks, efficient communication system between 119 and emergency health are center for prompt AED, and training and education program for AED.

• 가족자원경영과 정책
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• 제2권1호
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• pp.79-90
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• 1998

The main purpose of this study was to investigate the level of the soundness of home life. This study was focused to analyze the soundness of home life according to the objective variables and the psychological variables. It was not also to provide some fundamental information that helped to elevate the home life soundness, but also to prevent family problems. The subjects of this study was married female teachers living in Seoul area. The sample size was 237. The significant results were as follows: 1) The soundness of home life differed significantly according to age, income, the number of children, and family pattern among the objective variables. 2) The soundness of home life differed significantly according to self-actualization and internal-external of control. 3) The variables such as income, self-actualization and internal-external of control affected the soundness of home life.

• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 2000년도 춘계학술대회논문집 - 한국공작기계학회
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• pp.310-315
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• 2000

In this paper, the problems of the external fixator that have developed for a distal radius fracture so far are analyzed, and accordingly, the characterizations, which must have a prototype, are arranged. C-Arm is used. This instrument makes it possible for the real play of the internal body by x-ray permeability. From this data, it is possible to induce important design factors. Finally, a basic mechanism, which has to be applied, is decided, and the Solid Edge program, which used a 3-D design tool, completes then total instrument design.

• 대한기관식도과학회지
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• 제4권2호
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• pp.254-257
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• 1998

Esophageal foreign body are not uncommon problems in the otolaryngologic field. Esophageal foreign body may cause severe complications such as esophageal ulceration, esophageal perforation, periesophagitis, tracheo-esophageal fistula, mediastinitis, pneumothorax pyothorax according to the kinds, shape, size, duration of lodgement of foreign body. The majority of esophageal foreign U which lodge in the esophagus can be removed endoscopically, but the following type of foreign body may require removal by external route. 1. an impacted foreign body 2. a foreign body producing esophagitis after unsuccessful attempts at removal through the esopahgoscope 3. a periesophageal abscess with a foreign body lodging in the abscess itself. Recently, we experienced a case of esophageal foreign body (fish bone) which penetrate the cervical esophageal wall and formed retropharyngeal abscess in 54-year old female. The foreign body are successfully removed and abscess was drained by external route through the lat neck.

• 한방안이비인후피부과학회지
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• 제28권4호
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• pp.12-28
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• 2015

Objective : The purpose of this study is to analyse research trend on alopecia including androgenetic alopecia, alopecia areata, etc.Methods : We searched Pubmed, CNKI and OASIS on the title "alopecia" in recent 5 years.Results : We found 23 studies on Pubmed, 20 on CNKI, and 3 on OASIS about treatments of alopecia. The subjects of them were about 5α-reductase inhibitor, Minoxidil, steroids, immunosuppression, laser therapy, PRP, microneedling, stem cell, herbal medicine, integrative medicine, external treatments and syndrome differentiation.Conclusions : In recent studies in western medicine were about combination therapy or safety and presented validities and superiorities about new treatments. Integrative medicine, external treatment and researches about patients' characteristics were reported in TCM. Korean medicine has advantages of considering whole body and phychological problems.

• 대한조선학회논문집
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• 제51권5호
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• pp.362-368
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• 2014

Container vessel sizes have constantly increased over the past two decades. With increasing ship sizes and higher container loading capacities, the adoption of lashing bridges has also increased. Today's lashing bridge designs range from 1st tier to 3rd tier lashing bridges. Container securing program of the past which is based on two lashing rods and 1st tier lashing bridge has to be improved to be suitable for the present time. The equilibrium equations in this study are established to cover the application of 3~4 lashing rods and 2nd~3rd tier lashing bridges. In addition developed program is improved to be able to calculate the reaction forces and optimum arrangement under the external lashing. An optimization algorithm which is suitable for the container securing problems involved the equality constraint has been also adopted in this study.

• 산업공학
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• 제22권4호
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• pp.359-367
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• 2009

The vehicle travel time between the demand points in downtown area is greatly influenced by complex road condition and traffic situation that change real time to various external environments. Most of research in the vehicle routing problems compose vehicle routes only considering travel distance and average vehicle speed between the demand points, however did not consider dynamic external environments such as traffic situation by service time zones. A realistic vehicle routing problem which considers traffic situation of smooth, delaying, and stagnating by three service time zones such as going to work, afternoon, and going home was suggested in this study. A mathematical programming model was suggested and it gives an optimal solution when using ILOG CPLEX. A hybrid genetic algorithm was also suggested to chooses a vehicle route considering traffic situation to minimize the total travel time. By comparing the result considering the traffic situation, the suggested algorithm gives better solution than existing algorithms.

• 전기학회논문지
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• 제59권11호
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• pp.2089-2092
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• 2010

There are many cases that interrupt the production process because of malfunctions caused by electronic circuit boards which control equipment, but it is difficult to distinctly identify the causes in many cases. Especially, CMOS devices with the control logic circuit return automatically to normal state after their own faults. Therefore it is not easy to analyze the problems with electronic circuit boards. Recently, nuclear power plant experienced a failure due to the malfunction of electronic circuit boards and it was identified that the reason of the malfunction was because of latch-up phenomenon caused by external surge in electronic devices. This paper presents the causes and the phenomenon of latch-up by experiment and also a way using counter EMF diodes, noise filters and surge protective devices to prevent latch-up phenomenon from electronic circuit boards, finally confirms the effectiveness of the result by experiment.