• 천문학회보
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• 제38권2호
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• pp.94.1-94.1
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• 2013

Whistler mode chorus waves, which are observed outside the plasmasphere of the Earth's magnetosphere, play a major role in accelerating and scattering energetic electrons in the radiation belts. In this study we developed a predicting scheme of the global distribution of chorus by using the Time History of Events and Macroscale Interactions during Substorms (THEMIS) satellite data. First, we determined global spatial distributions of chorus activity, and identified fit functions that best represent chorus intensities in specific L-MLT zones. Second, we determined the specific dependence of average chorus intensity on preceding solar wind conditions (e.g., solar wind speed, IMF Bz, energy coupling degree) as well as preceding geomagnetic states (as represented by AE, for example). Finally, we combined these two results to develop the predicting functions for the global distribution and intensity of chorus. Implementing these results in the radiation belt models should improve the local acceleration effect by chorus waves.

• 한국연소학회:학술대회논문집
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• 한국연소학회 2012년도 제45회 KOSCO SYMPOSIUM 초록집
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• pp.129-132
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• 2012

Computation is performed to predict number density, volume fraction and size distribution of soot particles in typical operating conditions of a diesel engine. KIVA has been integrated with the CMC routine to consider turbulence/chemistry coupling and gas phase kinetics for heat release and soot precursors. The compositions of soot precursors are estimated by tracking Lagrangian particles to consider spatial inhomogeneity and differential diffusion in KIVA. The soot simulator SWEEP is employed as a postprocessing step to calculate conditional and integral quantities of soot particles.

• Journal of Power Electronics
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• 제12권2호
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• pp.368-376
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• 2012

This paper deals with an optimization approach of 3D space placement of power components under volume and thermal constraints. It consists in optimizing semiconductors positions on a heat sink by respecting the components junction temperatures and minimizing the heat sink size. The aim is to remove risks on the 3D converter components placement and ensure their effective integration before carrying out the first physical prototype. This approach is based on coupling an optimization environment with a thermal finite element simulation tool. A pre-sizing step using analytical models is performed to set the optimization computations coupled to numerical simulation.

• 한국측량학회:학술대회논문집
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• 한국측량학회 2010년 춘계학술발표회 논문집
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• pp.383-385
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• 2010

This study analyzed the change of flowout and suspend solid in Andong and Imha basin according to the climate change to develop evaluation index about turbid water occurrence possibility and to support the countermeasures for turbid water management using GIS-based Soil and Water Assessment Tools (SWAT). MIROC3.2 hires model values of A1B climate change scenario that were supplied by Intergovernmental Panel on Climate Change (IPCC) were applied to future climage change data. Precipitation and temperature were corrected by applying the output value of 20th Century Climate Coupled Model (20C3M) based on past climate data during 1977 and 2006 and downscaled with Change Factor (CF) method. And future climate change scenarios were classified as three periods (2020s, 2050s, 2080s) and the change of flowout and suspended solid according to the climate change were estimated by coupling modeled value with SWAT model.

• 한국전자파학회논문지
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• 제11권2호
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• pp.228-233
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• 2000

본 논문에서는 무선광연결에서 끈사적 평균잡음검출을 이용한 차동검출방식에 대하여 소개한다 이 방식은 기존의 잠음광의 영향을 소거하는 차동검출기의 기능을 보완한다. 근사적 평균잡음전압을 이용하여 차동검출하면. 물체나 사람의 이동에 의하여 나타날 수 있는 잡음광 결합비의 순간적 변화에 의한 출력전압의 변동을 줄일 수 있다 이 것은 장음광의 공간적 분포가 수시로 변동하는 환경에서 무선광연결을 구성하는 경우 잡음광을 소거하는 데에 매우 효과적이다

• Journal of the Optical Society of Korea
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• 제13권4호
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• pp.439-444
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• 2009

Accurate evaluation of polarization characteristics in the integrated optic chip (IOC) for interferometric fiber optic gyroscope was performed. Spatial distribution of optical wavetrains caused by the polarization parameters such as local polarization cross-coupling and polarization rejection coefficient of the IOC were measured utilizing the path-matched optical coherence domain polarimetry (PM-OCDP). With the analytic model deduced from Jones matrix representation, we could accurately identify the polarization characteristics of the IOC. Both degree of measurement error due to the imperfect equipment conditions in PM-OCDP and birefringence of IOC chip were also characterized.

• 한국실내디자인학회논문집
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• 제15권6호
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• pp.178-187
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• 2006

The purpose of this study was analyze the space organizational characteristics of heath facilities for the elderly in Japan, in order to refer them in establishing the planning direction in Korea. Therefore the 79 architectural drawings, which was gathered through mailed self-reported questionnaires in Japan and standard of heath facilities for the elderly have been analysed for this study. The results of the study were following: The spatial composition was categorized into living space, public use space, nursing, medical treatment, management, provision, and home assistance, and daycare. Moreover, coupling method of respective space was diversity according to inmate satisfaction measurement and form of service. In order to do that, this study has classified type of health facilities into 6 types on the basis of the space of position and space organization characteristics. Therefore study shows the functional relationships of spaces, the proportions of departmental areas in each type.

• Nuclear Engineering and Technology
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• 제55권2호
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• pp.648-654
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• 2023

A dual-particle imager (DPI) is configured in a hand-held form factor, then one can efficiently and conveniently deploy the DPI to detect the presence of special nuclear materials (SNM) and identify any isotopic variations that differ from their natural abundances. Here we show that by maximizing the areal coupling between a pixelated scintillator array and the partitioned photosensor readout such as a silicon photomultiplier (SiPM), the information utilization of the gamma-ray and neutron information in the radiation field can be enhanced, thus enabling one to rapidly acquire spatial maps of the distributions on gamma-ray and neutron emitters.

• 한국지리정보학회지
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• 제7권4호
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• pp.155-165
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• 2004

유역의 수자원 분석을 위해서는 대상 유역의 특성 및 목적에 적합한 모형을 사용하여야 한다. 그러나 적합한 모형이 사용된다고 하더라도 사용되는 자료의 객관성과 타당성이 낮을 경우에는 기대하는 결과를 도출하기 어렵다. 따라서 선정된 모형의 입력자료와 이를 바탕으로 추정된 매개변수의 결정이 매우 중요하다고 할 수 있다. 본 연구에서는 수문모형의 입력자료인 유역의 시간자료와 공간자료를 구축하고 이를 대상유역의 기준자료로 선정하여 HyGIS(hydrological geographic information system) 의 시 공간DB에 저장하였다. 또한 TOPMODEL을 HyGIS와 연계시킴으로서 저장된 DB로부터 모형 구동에 필요한 시 공간자료를 손쉽게 사용할 수 있는 시스템을 개발하였다. 본 연구에서 개발한 시스템은 TOPMODEL에서 필요로 하는 시 공간 자료를 HyGIS의 DB로부터 입력하며, 매개변수를 결정하기 위해서는 유전자 알고리즘을 사용하였다. 연구결과 HyGIS의 시 공간DB는 TOPMODEL의 입력자료를 구성하고 매개변수를 추정하는데 효과적으로 사용될 수 있는 것으로 나타났으며, 향후 다양한 수자원 분석모형과 연계될 경우에도 적합하게 적용될 수 있는 가능성을 제시하였다.

• 한국습지학회지
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• 제16권4호
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• pp.389-402
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• 2014

본 연구에서는 기존에 구축 운영 중인 COSFIM과 FLDWAV간 연계를 통해 다기능보 상 하류 구간 등 하천내 주요 관심구간에 대한 1차원 및 2차원 수리분석을 수행할 수 있는 시스템을 개발하고 낙동강 8개 다기능보를 대상으로 사업 전 후 수리특성 분석을 수행하였다. 각 수치모형은 활용목적에 따라 장 단점을 가지고 있기 때문에 상황에 적합한 모형을 선택적으로 활용할 수 있을 것이며, 기존의 1차원 수리 수문 모형으로 분석할 수 있었던 선 개념 지점 개념의 정보 뿐 아니라 추가적으로 공간 격자 개념의 정보를 제공받을 수 있는 다차원 모의를 수행함으로써 하천에서의 물리적 현상을 적절히 고려한 공간적 수리특성을 반영한 하천관리가 가능할 것이다.