• 대한전기학회:학술대회논문집
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• 대한전기학회 1990년도 하계학술대회 논문집
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• pp.147-153
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• 1990

This paper treats modeling of dynamic load characteristics for power for systems. The dynamic load is represented as 4th order multivariable ARMA model under the assumption that the dynamic load characteristics can be described by the dynamics of only one induction motor. The parameters of the proposed ARMA model are identified using the well-known RLS method. This paper presents two kind of identification results : one is for induction motors and the other is for field data at Donghae station. From these results, the proposed model is quite suitable for the dynamic load characteristics. It has, however, a disadvantage in the viewpoint that the identified parameters are not those of the induction motor.

• 한국식생활문화학회지
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• 제17권5호
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• pp.584-593
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• 2002

The purpose of this study was to evaluate the diet quality of the menus delivered by 17 free meal service centers for the low-income home-bound elderly in Chung- cheong buk-Do. Statistical data analysis was compleleted using the SPSS package program for descriptive analysis, T-test, and ANOVA. The meals offered by free meal service centers were not met the 1/3 recommended dietary allowances in calcium and vitamin $B_2$. There were significant differences between dependent variables(nutrient content, nutrient density, nutrient deficiency, NAR, MAR, food group intake patterns) and independent variables (operation type, operation status, operation period, nutritionist, food cost).

• 대한지리학회지
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• 제33권2호
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• pp.127-142
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• 1998

Unsan alluvial plain is the backmarsh of Seomseokcheon which is a river originated from Chilseongdae(954m) on Mts Taeback, flowing into Donghae in southern Kangreung City, Kangwon Province. The vegetation change, geomorphic develoopment and depositional environment during the late Holocene have been investigated, using the methods such as boring, pollen analysis and radiocarbon dating. Because the deposits fo the study area are mainly consisted of peat and paety sand, they contained many pollen fossils. The peat layer has been sedimented since the high sea-level periods, 3,200 y. BP, and the records of vegetation change until now has well preserved here. According to archeological researches and the results of pollen analysis in east coast of Korea, it is supposed that the prehistoric rice farming in this area has begun since ca. 1,800 y. BP.

• Tuberculosis and Respiratory Diseases
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• 제63권6호
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• pp.507-510
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• 2007

폐렴의 합병증으로 생긴 기관지 늑막강루의 치료로 최근 들어 비침습적 방법으로 기관지 내시경을 이용한 치료가 보고되고 있지만 그 사용 물질 및 방법은 다양하다. 본 증례에서는 혈관 폐쇄용 코일과 피브린 글루를 사용하여 굴곡형 기관지내시경을 이용하여 치료하였다. 기관지 늑막강루의 크기가 크지 않고 말초 기관지에 위치한다면 본 증례의 치료 방법이 고려될 수 있다.

• Journal of the Korean Data and Information Science Society
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• 제11권2호
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• pp.269-277
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• 2000

독립이면서 로그정규분포를 따르는 두 모집단의 평균 차이에 대한 검정으로 Berger와 Pericchi(1996, 1998)가 제안한 내재적 베이즈 요인(intrinsic Bayes factor)을 이용한 베이지안 방법을 제안한다. 이 때 모수에 대한 사전분포로는 무정보적 사전분포(noninformative prior)를 사용한다. 제안한 검정 방법의 유용성을 알아보기 위해 실제 자료의 분석과 모의실험을 이용하여 고전적인 검정 방범과 그 결과를 비교한다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1999년도 하계학술대회 논문집 E
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• pp.2345-2348
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• 1999

Existing $\psi$-AEA-t (phase-AEA-time) characteristic in polymer materials for power cable is good in general deterioration characteristic according to time variation, but it is difficult to clearly distinguish from deterioration state and diagnosis of deterioration is not enough to some extent. This paper is interpreted AE discharge statistics quantities measuring phase-amplitude variation of acoustic emission characteristic obtained from treeing breakdown experiment. Besides it can know useful discharge statistics quantities (AE average inception phase/amplitude, AE average maximum phase/amplitude) about so many for diagnosis of treeing deterioration.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1999년도 하계학술대회 논문집 E
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• pp.2349-2351
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• 1999

In this paper, the variable absorption rates and DC dielectric breakdown strength of epoxy composites were measured at boiling absorption condition in order to observe the influences of moisture in out door use. Also, in order to improve withstand voltage properties at moisture absorbtion condition. IPN (interpenetrating polymer network) method which had been already reported, was introduced and the influence was investigated. As a result, it was confirmed that the moisture absorption rate was increased and DC dielectric breakdown strength was degraded with boiling time and filler content increasing. On the other hand, it was confirmed that moisture absorption rate and DC dielectric breakdown strength degrading rate were lowered by the improvement of adhesion strength In IPN specimens.

• 한국음향학회:학술대회논문집
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• 한국음향학회 1996년도 제11회 수중음향학 학술발표회 논문집 11th Underwater Acoustics Symposium Proceedings
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• pp.51-54
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• 1996

동해 중부 연안(수심: 200 m)에서 해수 중 주위잡음을 측정하는 동안 태평양 흰줄무늬 돌고래(pacific white-sided dolphin, 학명: Lagenorhynchus obliquidens)의 발생음을 수신하였으며 그 음향 특성을 분석하였다. 그 결과 얻어진 결론을 요약하면 다음과 같다. 첫째, 돌고래 발생음의 파형은 임펄스의 형태로서 그것의 전체 길이는 0.25~60.50 ms였고, 처음에 음(-)의 방향으로 작은 진폭을 보였으며, 그 후 작은 진폭으로 빠르게 감쇠진동하고 있는 형태를 나타내었다. 둘째, 돌고래 발생음의 주파수 스펙트럼은 약 18~90kHz의 광범위한 성분을 포함하고 있었다. 셋째, 돌고래 발생음의 스펙트럼 레벨 피크는 주파수 범위 35~55 kHz에서 나타났으며, 이것은 돌고래의 발생음이 없는 경우 해수 중 주위잡음의 레벨에 비하여 약 30~40 dB 높게 나타났다.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2005년도 전력전자학술대회 논문집
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• pp.336-339
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• 2005

This paper presents a PM type BLDC(Brushless DC) Motor servo drive system using high performance DSP TMS320F2812. The DSP controller with 150MIPS enables an enhanced real time implementation and increased efficiency and high performance for motor drive. The suggested drive system consists of PI action for the constant speed control and PID action for the current control with only 3 Halls, no encoders. The developed servo drive control system shows a good response speed characteristics at high speed up to 10000 [rpm].

• 한국환경과학회지
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• 제14권6호
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• pp.613-619
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• 2005

Recently, we are suffered enormous loss from a natural disaster and making an effort to prepare measures for dealing with disasters. This study shows the major causes of natural disasters and stricken area with the analysis of meteorological data based on the Korean Meteorological Administration and the Central Disaster Relief Center records during 1987-2003 and classifies natural disasters according to the causes and damaged conditions. In this study, the most damaged area were Gangwon, Gyeongnam and Gyeongi province as a result of a typhoon and a localized heavy rain. To establish an effective disaster measure for these area, detailed prevention plans should be established by its causes after investigating precise regional damage data analysis.