• 분석과학
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• 제12권2호
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• pp.111-115
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• 1999

간접자외선흡광검출 이온크로마토그래피를 7가지 음이온($H_2PO_4^-$, $Cl^-$, $NO_2^-$, $NO_3^-$, $I^-$, $SO_4^{2-}$, $SCN^-$)분리에 적용하였다. 컬럼은 저용량의 강염기성 음이온 교환체를 가진 상용화된 TSK-guardgel QAE-SW (ca. 0.3 meq./g; 4.6 mm i.d${\times}$150 mm)를 사용하였다. 선택적이고 신속한 이온분리방법을 연구하기 위하여 naphthalene trisulfonic acid(NTS) 및 naphthalene disulfonic acid(NDS) 용리액에 대한 분리거동을 조사하였다. 더 나아가, 0.20 mM NTS 용리액에 5% 아세토리트릴을 첨가하여 음용수에 적용한 결과, 양이온과 음이온을 동시에 분리 할 수 있었다.

• Journal of the Korean Wood Science and Technology
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• 제39권5호
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• pp.444-450
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• 2011

The goal of this study is to investigate bending properties of domestic timber. Three representative structural timber from Larix kaempferi, Pinus koraiensis, and Pinus densiflora, in the northeastern South Korea were selected. Visual grading for the timber was conducted based on KFRI notification 2009-01 and the bending strength for the timber was evaluated based on ASTM D 198 bending. The high percentage of grade 1 and 2 for Larix kaempferi shows that the KFRI notification was optimized for this species. The bending strength distributions from Pinus koraiensis and Pinus densiflora were very similar. It could be possible to specify the allowable bending properties of these two Specification using a united species group similar to spruce-pine-fir. Lastly, the bending strength of $120{\times}180mm$ structural members was higher than both existing values in KBC 2009 and design values for timber of imported species described in the NDS. Thus, 120 mm thick domestic softwoods could replace the commercial imported species and the KBC should be modified to provide design values for both timber and dimensional lumber, respectively, like NDS.

• 한국초지조사료학회지
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• 제8권3호
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• pp.169-174
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• 1988

An experiment was conducted to determine the feeding value of Arundinella hirat silage making by different methods ie., added starch 3%, formic acid 1% (FA), anhydrous ammonia ($NH_3$) 3%, and dried poultry waste (DPW) 3%. The samples were analyzed organic acid, cell wall constituent (NDF), cell contents (NDS), lignincutin-silica (ADL), hemicellulose (H: CHO) and in vitro dry matter digestibility (DMD) by pepsin-cellulase technique. The feeding value of silages were compared with corn siiage. The results are summarized as follows; 1.Formic acid treated to silage was lower pH(4.0), but anhydrous ammonia (8.37) and DPW added silage (8.72) were higher than that of the other treatment silages. 2.Fermentative quality of corn silage, starch, DPW, $NH_3$, control and FA treated silage were marked 100,81, 77,63,62 and 58, respectively. 3.Silage with $NH_3$, (23.57%) and DPW (10.42%) of content of protein were higher than that of other treated silages. 4.Silage with $NH_3$, was significantly lower contents of NDF, but did not ADF of among the treated silages. 5.In the contents of ADL, starch added silage was significantly decreased (p < 0.05), but did not the other treatment. 6.DMD of in vitro by pepsin-cellulase of silage with starch was increased three folds as equal to corn silage but did not increased the other treated silages. 7.Correlationship of latic acid an total acid, and NDS were a positive but lactic acid and NDF was a negative correlation.

• KEPCO Journal on Electric Power and Energy
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• 제8권1호
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• pp.43-48
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• 2022

Although the distribution system has been structured as complicated as a mesh in the past, the connection points for each line are always kept open, so that it is operated as a radial distribution system (RDS). For RDS, the line utilization rate is determined according to the maximum load on the line, and the utilization rate is usually kept low. In addition, when a fault occurs in the RDS, a power outage of about 3 to 5 minutes occurs until the fault section is separated, and the healthy section is transferred to another line. To improve the disadvantages of the RDS, research on the construction of a networked distribution system (NDS) that linking multiple lines is in progress. Compared to the RDS, the NDS has advantages such as increased facility utilization, load leveling, self-healing, increased capacity connected to distributed generator, and resolution of terminal voltage drop. However, when a fault occurs in the network distribution system, fault current can flow in from all connected lines, and the direction of fault current varies depending on the fault point, so a high-precision fault current direction determination method and high-speed communication are required. Therefore, in this paper, we propose an accurate fault current direction determination method by comparing the peak value polarity of the fault current in the event of a fault, and a communication-based protection coordination method using this method.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2005년도 추계종합학술대회
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• pp.331-334
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• 2005

움직임 추정은 비디오신호의 압축에 중요한 역할을 한다. 본 논문은 효율적으로 움직임 벡터를 찾기 위하여 움직임 벡터의 시간적, 공간적 유사성을 이용하였다. 벡터를 검색하기 이전에 움직임 벡터의 검색 범위를 크게 9개의 영역으로 나눈 후, 이전 프레임에서 동일한 위치, 현재 프레임의 현재 매크로블록의 상위, 상우와 좌측의 매크로블록에서의 움직임 벡터까지 총 4개의 움직임 벡터를 이용하여 9개의 영역 중 한 영역을 제 1 후보, 그를 둘러싼 영역을 제 2 후보라 정하고 극소점들(Local Minima)을 피하였다. 모의실험을 통한 결과 NDS(New Diamond Search) 알고리즘에 비하여 매크로블록 당 평균 탐색 포인트 수가 5.79 포인트 감소하고, MSE는 최대 104.23 감소한 것을 확인할 수 있었다.

• 약학회지
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• 제42권3호
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• pp.233-237
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• 1998

Activity-guided fractionation and repeated column chromatography afforded two cytotoxic compounds R-3 and R-4 from the root of Rumex japonicus HOUTT. Compou nds were identified as musizin and emodin, respectively, by the physicochemical and spectral data. Besides R-3 and R-4, two compounds R-1 and R-2, chrysophanol and physcion, respectively, were also isolated. The compound R-3 and R-4 exhibited cytotoxicity against cultured human tumor cell lines, A-549, SK-OV-3, SK-MEL-2, XF498 and HCT15 with $ED_{50}$ values ranging from 2.68 to $10.06{\mu}g/ml$.

• 한국시뮬레이션학회:학술대회논문집
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• 한국시뮬레이션학회 2001년도 The Seoul International Simulation Conference
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• pp.280-287
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• 2001

There have been some studies about hybrid production system, which integrate push system and pull system. Most of them are based on the simple production system considering one product line. Though there are many studies about hybrid production system, it\`s not practical to implement them for real factory, because most of them did not consider various factors about real factory. On this study we designed hybrid production system considering some factor - one is automatic kanban generation, the other is dispatching rule for Multi-tasking worker, and the last one is the priority of kanban. At last, We give simulation results fur a real company, which produce various cameras in Korea.

• 전기의세계
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• 제22권3호
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• pp.35-48
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• 1973

This paper deals with wave propagations in solid state electron plasmas from the view point of treating the plasma as a conducting fluid, and especially consideration is extended to the effect of diffusion on the permittivities and dispersion relations. The analysis is based on the conception of the self-consistent field approximation. It is shown for the cases of the specific physical configurations that the positions of the null elements in the permittivity tensors are not affected by the diffusion terms, and the diffusion effect appears only in the case of the space-charge wave. It is also shown that the magnitude of the real part of wave vector is in proportion to the 3/2nds power of the field in some regions.

• 한국정보처리학회:학술대회논문집
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• 한국정보처리학회 2014년도 춘계학술발표대회
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• pp.934-935
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• 2014

CMS(Contents Management System)는 웹사이트에서 지원되는 다양한 콘텐츠를 효율적으로 관리할 수 있도록 지원하는 소프트웨어 시스템으로서 B2C용 콘텐츠 관리 시스템, B2B 전자상거래에 필요한 전자 카탈로그 관리시스템 등을 포함하는 개념으로 활용되고 있다. 제조사별 DRM 폐쇄성을 극복하고 전자책을 제공하는 업체별로 제공하는 CMS를 통합 구축하여 전자책 사용자와 도서관 관리자의 불편을 최소화한다. 이를 위해, 통합 CMS는 유무선 인터넷 환경에서 구동할 수 있도록 개발하며 사용자 UI, 관리자 UI, 데이터베이스, 유무선 통신 모듈, 보안 모듈을 개발을 통해 표준 DRM에 필수적인 요소를 추출하고 이를 바탕으로 실제 표준 DRM을 개발할 수 있는 토대를 구축한다.

• 한국ITS학회 논문지
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• 제16권5호
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• pp.96-108
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• 2017

기존의 첨단 운전자 지원 시스템 (Advanced Driver Assistance System, ADAS)들은 전방 위험탐지와 같은 한정적 상황에서의 사고 예방에 집중하고 있어 다양한 사고 시나리오가 존재하는 교차로에 적용하기에는 한계를 가지고 있다. 또한 기존 연구는 주로 사고 요인 분석에 집중하고 있어 첨단 운전자 지원 시스템의 사고 예방 성능에 관한 연구는 미비한 편이다. 이에 본 연구에서는 비전 및 레이더 센서 기반 첨단 운전자 지원 시스템의 다양한 교차로 사고 예방에 대한 성능을 평가하고 대책을 마련하고자 한다. 이를 위하여 미국의 Second Strategic Highway Research Program(SHRP2)의 naturalistic driving study(NDS)에서 수집된 사고/준사고 상황의 거리 측정 데이터를 기반으로 16개의 교차로 사고 시나리오를 도출하였고, 총 363건의 차량과 차량 간 사고를 분석하였다. 분석 결과 16개의 사고 시나리오 중 0.7의 사고 예방율을 기준으로 카메라 기반 시스템은 5개, 레이더 기반 시스템은 4개의 사고 시나리오에서 사고를 예방할 수 있었다.