• 한국농림기상학회지
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• 제12권2호
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• pp.107-121
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• 2010

본 연구에서는 한반도의 주요 생태계인 활엽수림과 농경지에서 지면 모형 JULES(Joint UK Land Environment Simulator)으로 모의한 총일차생산량 (Gross Primary Productivity: GPP)과 생태계 호흡량 (ecosystem respiration: RE)의 수치 모사 결과에 영향을 미치는 주요 모수를 파악하였으며, 민감한 모수에 대해 실측자료를 사용함에 따른 모형 예측력의 개선 정도를 평가하였다. 민감도 실험의 결과, 활엽수림과 농경지에서 모두 JULES로 모의한 GPP는 잎 내부의 질소농도와 리불로오스이인산(RuBP) 카르복실화의 최대 속도에 가장 민감하였다. RE는 활엽수림에서는 목질부 탄소량과 엽면적지수를 연결시켜주는 상수에 가장 민감하였다. 반면에 농경지에서 수치모사된 RE는 GPP와 같이 각각 잎 내부의 질소 농도와 RuBP 카르복실화의 최대 속도에 가장 민감하였다. JULES로부터 제공된 모수의 값으로 모의된 두 지역의 GPP와 RE는 모두 관측값에 비해 과대평가되었다. 특히 활엽수림에서 GPP가 가장 민감하게 반응했던 잎 질소 농도의 실제 관측값이 모형에서 사용하는 기존 설정값의 50% 이하임을 고려할 때 모형에서 설정된 모수의 값으로 탄소 순환을 수치 모사할 경우에 모수의 기존 설정값과 실제값의 차이가 모형의 과다모의에 상당한 영향을 미침을 확인할 수 있었다. 따라서 한반도 탄소순환의 현실적인 모의를 위해서는 모형에서 요구되는 생물리학적 정보가 한반도 다양한 식생 기능 형태를 현실적으로 잘 반영하는지를 확인해야 할 뿐 아니라 지속적인 현장 관측을 통해서 생물리학적 정보와 관련된 자료기반을 마련하는 것이 중요하다.

• Journal of applied mathematics & informatics
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• 제31권5_6호
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• pp.631-642
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• 2013

In this paper we reconsider the problem of steady mixed convection boundary-layer flow over a vertical flat plate studied in [6],[7] and [13]. Under favorable assumptions, we prove existence of multiple similarity solutions, we study also their asymptotic behavior. Numerical solutions are carried out using a shooting integration scheme.

• Nuclear Engineering and Technology
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• 제38권5호
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• pp.437-442
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• 2006

European Material Test Reactors (MTRs) have provided essential support for nuclear power programs over the last 40 years. MTRs are now ageing in Europe and they cannot ensure the securing of experimental capability for the next decades. In this context, a new Material Testing Reactor, named Jules Horowitz Reactor -JHR-, operated as an international user-facility, is under development in Europe. The European MTRs context and the JHR objectives and status will be presented. Emphasis will be put on experiments in the field of nuclear fuels and materials irradiation which are developed in the framework of European and international collaboration.

• 한국수학사학회지
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• 제14권2호
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• pp.45-54
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• 2001

Jules Henri Poincare was great not only as a mathematician brit also as a philosopher of science. He received many honors for his outstanding research. He was elected to the Academie des Sciences in 1887 and was elected President of tile Academy in 1906. In 1908 he was elected to the Academie Francaise and was elected director in the year of his death. The Poincare Conjecture was selected Millennium Prize Problems fly The Clay Mathematics Institute of Cambridge, Massachusetts(CMI). The Board of Directors of CMI have designated a $1 million prize fund for the solution to his problem. In this paper, Poincare's major works, his life, his philosophy and the Poincare Conjecture are given.

• Natural Product Sciences
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• 제12권1호
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• pp.62-66
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• 2006

A steroidal saponin, $3-O-{\alpha}-L-rhamnopyranosyl-(1{\rightarrow}2)-[{\alpha}-L-rhamnopyranosyl-(1{\rightarrow}3)]-{\beta}-D-glucopyranosylpennogenin$ ;(1, spiroconazole A) was isolated from the tubers of Dioscorea bulbifera L. var sativa and $^1H-and\;^{13}C-NMR$ assignment was completed using HMBC correlation. In addition, four phenolic substances, 2,7-dihydroxy-4-methoxyphenanthrene (2), quercetin (3), $quercetin-3-O-{\beta}-D-glucopyranoside$ (4), and $quercetin-3-O-{\beta}-D-galactopyranoside$ (5) were also isolated.

• Journal of Electrical Engineering and Technology
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• 제8권5호
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• pp.1202-1211
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• 2013

This paper deals with a robust controller for an induction motor (IM) which is represented as a linear parameter varying systems. To do so linear matrix inequality (LMI) based approach and robust Lyapunov feedback are associated. This approach is related to the fact that the synthesis of a linear parameter varying (LPV) feedback controller for the inner loop take into account rotor resistance and mechanical speed as varying parameter. An LPV flux observer is also synthesized to estimate rotor flux providing reference to cited above regulator. The induction motor is described as a polytopic LPV system because of speed and rotor resistance affine dependence. Their values can be estimated on line during systems operations. The simulation and experimental results largely confirm the effectiveness of the proposed control.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1991년도 한국자동제어학술회의논문집(국내학술편); KOEX, Seoul; 22-24 Oct. 1991
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• pp.793-798
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• 1991

Implementation of AGVS (Automated Guided Vehicle System) in CIMS (Computer Integrated Manufacturing System) generally requires substantial study to optimize design and performance of the guide path. Traditional mathematical approaches have been used with limited success to analyze AGVS. These approaches, however, do not provide a practical opportunity to use by path designers. This paper presents a new approach based on Jules in designing and assessing AGV path to have better design of the closed-loop layout. A framework for the approach is proposed and a case study is reported to demonstrate the framework. Deletion of seldom used paths and addition of bypasses to solve the congestion problem are conducted automatically through simulation expefiments. To visualize die results a graphic control program is developed and integrated with AutoMod/AutoGram simulation package.

• Natural Product Sciences
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• 제15권2호
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• pp.76-82
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• 2009

Phytochemical investigation of the EtOAc and n-BuOH fractions obtained from the crude methanol extract of the seeds of Butyrospermum parkii led to the isolation of seven compounds including 1${\beta}$,2${\alpha}$,3${\alpha}$-trihydroxyurs-12-en-28-oic acid (1${\beta}$-hydroxyeuscaphic acid) which full NMR assignment is herein reported for the first time. The above extract, fractions and some of the isolated compounds were screened for antimicrobial and antioxidant activities; 1${\beta}$-hydroxyeuscaphic acid was the more potent.

• Structural Engineering and Mechanics
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• 제26권1호
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• pp.87-97
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• 2007

Some mixed mode fracture criterion may be converted in to elliptical or ellipsoidal formula with the aid of mathematical translation. Hence, the crack initiation in mixed mode fracture I+II emanating from notches, has been studied using notched circular ring specimens. On the basis of Irwin (1957) theory, a new criteria in mixed mode fracture I+II, based fracture elliptic criterion and notch stress intensity factors has been developed.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2018년도 학술발표회
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• pp.308-308
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• 2018

전 지구적으로 댐 건설과 가정, 공업 및 농업 용수의 사용 등 인간의 영향으로 유출량, 지하수, 토양수분 등의 다양한 수문요소가 변화를 보이고 있다. 이러한 인간의 영향은 기후변화의 영향과 함께 수문요소에 주요한 동인으로 이의 영향을 이해하고 전망할 필요가 있다. 본 연구는 Inter-Sectoral Impact Model Intercomparison Project를 통해 이용 가능한 여러 글로벌 수자원 모형의 결과를 분석하여 기후변화 및 인간활동의 영향의 상대적 중요성 등을 분석하고자 한다. GFDL, HadGEM, IPSL, MIROC5에서 도출된 기후 시나리오를 기반으로 구동된 글로벌 수자원 모형결과를 살펴보고자 하며, 글로벌 수자원 모형은 CLM, H08, JULES 등을 포함한다. 본 연구에서는 증발산량, 토양수분, 유출 등의 시간 및 공간적 변화, 기후변화 및 인간 활동의 영향이 주요한 역할을 하는 지역 혹은 유역을 확인하는데 초점을 맞추고자 한다.