• Korean Journal of Agricultural and Forest Meteorology
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• v.12 no.2
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• pp.107-121
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• 2010

We conducted a sensitivity test of Joint UK Land Environment Simulator (JULES), in which the influence of biophysical parameters on the simulation of gross primary productivity (GPP) and ecosystem respiration (RE) was investigated for two typical ecosystems in Korea. For this test, we employed the whole-year observation of eddy-covariance fluxes measured in 2006 at two KoFlux sites: (1) a deciduous forest in complex terrain in Gwangneung and (2) a farmland with heterogeneous mosaic patches in Haenam. Our analysis showed that the simulated GPP was most sensitive to the maximum rate of RuBP carboxylation and leaf nitrogen concentration for both ecosystems. RE was sensitive to wood biomass parameter for the deciduous forest in Gwangneung. For the mixed farmland in Haenam, however, RE was most sensitive to the maximum rate of RuBP carboxylation and leaf nitrogen concentration like the simulated GPP. For both sites, the JULES model overestimated both GPP and RE when the default values of input parameters were adopted. Considering the fact that the leaf nitrogen concentration observed at the deciduous forest site was only about 60% of its default value, the significant portion of the model's overestimation can be attributed to such a discrepancy in the input parameters. Our finding demonstrates that the abovementioned key biophysical parameters of the two ecosystems should be evaluated carefully prior to any simulation and interpretation of ecosystem carbon exchange in Korea.

• Journal of applied mathematics & informatics
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• v.31 no.5_6
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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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• v.38 no.5
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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.

• Journal for History of Mathematics
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• v.14 no.2
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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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• v.12 no.1
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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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• v.8 no.5
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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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• 1991.10a
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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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• v.15 no.2
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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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• v.26 no.1
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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.

• Proceedings of the Korea Water Resources Association Conference
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• 2018.05a
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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.