• 전기학회논문지
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• 제58권12호
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• pp.2342-2348
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• 2009

Even though underground transmission cable is an essential transmission method to supply stable power for downtown and population center, the interaction of electromagnetic force by fault current is very large comparing to overhead transmission line due to restricted installation space such as tunnel, and close consideration is required for it. This paper presents countermeasures to reduce and release the effect of electromagnetic force with rope binding and installation of spacer and describes its efficacy through three phase short-circuit test, which will be utilized as basic materials for improvement and development of cleat, hanger, etc. to reduce and release effect of electromagnetic force in the future.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2007년도 제38회 하계학술대회
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• pp.913-914
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• 2007

Power transformer shall be designed and constructed to withstand the mechanical and thermal stresses produced by external short circuits which include three-phase, single line to ground, double line-to-ground, and line-to-line faults on any one set terminals at a time. This paper presents the method of short-circuit test and means of evaluation during and after each test to judge the results of short-circuit tests.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1999년도 하계학술대회 논문집 C
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• pp.1186-1188
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• 1999

When we perform the test related to the power distribution system such as artificial fault test, protective coordination test, distribution automation test in short length test line, Lumped Constant Circuit, a kind of variable impedance, should be attached to the test line in order to make it equivalent to a real line in length electrically. In this paper we designed the positive sequence and zero sequence Lumped Constant Circuit with optimized inductor and resister for the modification of long, 16km, distribution line, when they are attached to the short, 4km, distribution test line.

• 대한한의학회지
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• 제32권4호
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• pp.75-82
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• 2011

Objectives: This case report aimed to evaluate whether oriental medical treatment was effective on ADHD through a records review of a local oriental medical clinic. Methods: We reviewed clinical charts of a local oriental medical clinic between December 2007 and September 2010 to select ADHD patients. Among those patients, for comparison before and after treatment, we selected cases which had at least twice Stroop test results and 2 months of treatment. Baseline, 3-month and 6-month Stroop test results were compared. Oriental medical treatment consisted of 2 months' herbal medicine, periodic acupuncture and exercise. Results: 1. 3-month data showed that subjects were 12 and improved word score and word-color score of Stroop test. 2. 6-month data showed that subjects were 20 and improved word score, color score, and word-color score of Stroop test. Conclusions: 1. Relatively short term herbal medication and exercise are effective on the word score and word-color score of the Stroop test. 2. After short term herbal medication, continuous exercise maintained the effects of short term oriental medical treatment. 3. We need to consider the balance of left and right as an important point of exercise, but further study is needed.

• Fisheries and Aquatic Sciences
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• 제9권1호
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• pp.38-43
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• 2006

We developed and evaluated a method of short-term acute toxicity testing based on the feeding behavior of Ceriodaphnia dubia. In prior toxicity tests, neonates of C. dubia were hatched and cultivated with the addition of yeast only for the preparation of the transparent daphnid's gut. Scenedesmus subspicatus was supplied as food after 1 to 6 h of exposure to toxicants. The effects of 1-h and 6-h exposure time on test sensitivity did not significantly differ. A comparison of the short-term l-h acute toxicity test developed in this study to the standard 48-h acute toxicity test using heavy metals, cyanide, and pentachlorophenol indicated that the 1-h test provided an acceptable sensitivity level in toxicity testing of C. dubia..

• Journal of Electrical Engineering and Technology
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• 제9권1호
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• pp.286-292
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• 2014

This paper presents the parameters optimization technology for generating the first short stroke lightning current waveform($10/350{\mu}s$) which is necessary for the performance tests of components of lightning protection systems, as required under IEC 62305 and the newly amended IEC 62561. The circuit using the crowbar device specified in IEC 62305 was applied to generate the lightning current waveform. To find the proper parameters of the circuit is not easy because the circuit consists of two parts; circuit I, which relates to the front of current waveform, and circuit II, which relates to the tail. A simulation in PSpise was carried out to find main factors related to the front and tail of $10/350{\mu}s$. The lightning current generator was developed by utilizing the circuit parameters found in the simulation. In the result of experiments, new parameters of the circuits need to be changed because of the difference between the simulation and the experiment results. Using the iterative method, the optimized parameters of the circuits was determined. Also a multistage-type external coil and a damping resistor were proposed to make the efficiency of generation to enhance. According to the result in this paper, an optimized first short stroke lightning current waveform was obtained.

• 음성과학
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• 제15권2호
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• pp.119-129
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• 2008

The purpose of this study were to develop short form versions of MacArthur-Bates Communicative Development Inventories - Korean and to discuss clinical implications. Two short versions were developed: one for $9\sim17$ month-olds(including 69 words and 17 object manipulation skills) and the other for $18\sim35$ month-olds (including 128 words and 5 grammatical items). Short versions seemed to be representative of full versions and showed developmental validity. Short versions showed concomitant validity with SELSI which is a standardized test for Korean children under 37 month-olds. Norm tables for words and criteria for object manipulation and grammaticality are also provided. M-B CDI-K short versions could be used as a preliminary screening tool to identify Korean children with language impairment economically and efficiently. Cautions using short versions of M-B CDI-K are discussed.

• 한국환경과학회지
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• 제16권4호
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• pp.425-432
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• 2007

The water flea has been used as a test organism of toxicity test for surface water. Toxicity test with water flea is categorized into two parts. One is acute toxicity test with observing immobility and mortality and the other is chronic toxicity test determined by survival and reproduction of water flea. Heartbeat measurement of water flea was designed as a short-term toxicity test in this study. Direct measurement of heartbeat under microscope by aid of video camera gives and early diagnosis of mortality in short time. Therefore, the effects of measuring illumination, measuring time, and non-feeding during the test on heartbeat of water flea was evaluated to establish a new test approach. Test organisms used in this study are Daphnia magna, a well standardizes toxicity test organism, and Simocephalus mixtus, a newly refined organism $IC_{50}$ values of these test organism by heartbeat measurement were compared and discussed. It was found that toxicity test by heartbeat measurement was a reproducible, easy and simple method accomplished in a few hours.

• 해양환경안전학회지
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• 제18권6호
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• pp.591-596
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• 2012

안전하며 친환경적인 근해운송시스템을 확보하기 위해서는 운송 수단인 선박의 안전한 운항 확보가 필수적이다. 특히 좌초, 충돌 등의 해난사고를 방지하기 위해서는 선박이 우수한 조종성능을 갖는 것이 요구되며 특히 조종성능 중에서 선회성능은 충돌 회피 등에 필수적인 성능이다. 본 연구에서는 선박에 부착된 조타기의 타력 증가가 선박의 선회성능에 미치는 영향을 모형선 실험을 통하여 고찰하였다. 먼저 Coanda 효과를 이용한 고 양력 타 장치 모형과 47 K PC의 모형선을 제작하였다. 또한 모형선의 선회 성능 실험을 위한 자유항주시스템을 구축하고 사각 수조에서의 타력 증가 값을 변화시켜가면서 모형선의 선회 성능을 계측하여 타력 증가에 따른 선회 성능의 변화를 평가하였다. 모형선의 선회성능 실험결과를 통해 타력 증가가 근해운송 선박의 선회 성능 향상에 효과적인 것을 확인하였다.

• 한국도로학회논문집
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• 제7권4호
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• pp.203-210
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• 2005

바인더의 노화로 인한 성능변화는 침입도 또는 점도시험을 실시하여 판정하여왔다. 기존의 시험방법으로 아스팔트 바인더의 점탄성 특성과 실제거동을 평가할 수 없기 때문에 새로운 분석방법이 요구되어 왔다. 본 연구에서는 기존시험 방법을 사용하여 침입도지수와 잔류침입도를 판정하였고, 양방향 반복회전 모드와 일방향 반복회전 모드 시험을 실시하여 단기 노화된 아스팔트 바인더의 유변학적 특성을 분석하였다. 시험결과 단기 노화된 아스팔트 바인더는 시험주기(frequency) 즉, 차량속도의 변화에 따라 서로 다른 복합계수와 위상각을 나타냈으며 단기 노화 전후의 크리프 컴플라이언스 및 전단점도 시험결과에도 영향을 미치는 것으로 나타나서 포장 설계시 이러한 특성이 고려되어야 한다.