• 한국소음진동공학회논문집
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• 제14권8호
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• pp.668-674
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• 2004

The possibility of global noise reduction by the sound power control through selection of distribution and impedance of absorptive materials is discussed. It is necessary to investigate the relation between the global sound energy in the field and the total sound power radiated by sources. In the previous work,$^{(1.2)}$ the authors presented a useful design method to change boundary condition that can be useful to reduce noise in acoustically small enclosures. Changing boundary condition Is related to not only enclosure’s geometrical shape but also acoustical treatment on walls for example, attaching of impedance patches (ex: absorptive material). In many practical situations, we often meet situation to change acoustical treatment on walls. The possibility of total acoustic potential energy(globa1 noise) reduction by acoustic source power control is examined in an acoustically small cavity Using acoustic energy balance equation, the relation between global noise control performance and absorptive material’s arrangement/impedance is deduced. Numerical simulation is performed to interpret its physical meaning in terms of absorbent’s distribution and impedance.

• 한국제4기학회지
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• 제13권1호
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• pp.53-65
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• 1999

기후변화와 이에 따르는 식생변화, 인위적인 토지이용 변화 등 '지역환경생태시스템의 변화'에 대한 '지역 물수지변화' 추정은 오직 필자가 개발한 BROO $K_{TOP}$과 같은 '물리기반 물수지 모델(Physical based Water Balance Model)'류에 의해서만 가능하다. 본 연구에서는 독일 중북부 농업지대와 산림지대에 대해서 $BROOK_{TOP}$ 소프트웨어를 이용하여 정립된 물리기반 지역물수지모델에 독일 포츠담 기후변화연구소(PIK) 시나리오와 체코 프라하대학에서 개발한 중부유럽 대상 GCM 기후변화 시나리오를 적용하여 물수지변화를 추정하였다. 이와 같은 기후와 지표.지하조건을 고려 한 지구온난화에 따른 수자원변화 예측시스템 개발은 하천수$\cdot$지하수 개발 및 수질 관리, 농업경작관리, 환경생태계 관리, 자연 재해 관리, 토지이용계획 및 지역개발계획 등을 위한 시스템개발의 기반이 된다

• 한국멀티미디어학회논문지
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• 제3권3호
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• pp.309-319
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• 2000

병렬 스케줄링의 목적은 다중프로세서 시스템 환경에서 병렬성을 가진 응용프로그램에 대해 최소의 동기화 오버헤드와 부하균등(load balance)을 달성하도록 스케줄링을 수행하는데 있다. 프로세서들이 병렬 반복(iteration)을 실행하기 위해서는 메모리로부터 반복들에 대한 chunk를 계산하고 할당받게 된다. 이때, 전역 메모리의 상호 배타적인 빈번한 접근으로 많은 스케쥴링 오버헤드 및 병목현상이 발생된다. 또한, 프로세서에게 할당된 chunk내 병렬 반복들의 분포가 서로 상이한 경우,각 chunk의 실행시간이 서로 달라 부하불균등의 원인이 되어 결과적으로 전체 스케쥴링 성능에 나쁜 영향을 준다. 따라서, 최소의 스케줄링 오버 헤드와 부하균등을 달성하기 위해 본 논문에 서는 기존의 방법들에서 문제점들을 도출하고, 자료의 국부성과 프로세서 동족성(affinity)을 고려한 병렬 루프 스케줄링 알고리즘을 제안한다.

• The Journal of Asian Finance, Economics and Business
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• 제8권11호
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• pp.47-66
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• 2021

Despite the dominance of the USD as a vehicle currency in non-US trade, most studies on the exchange rate-trade balance relationship ignore its importance. Some recent J-curve papers have proved that incorporating the role of USD as vehicle currency as a crucial determinant of trade balance can well reflect the reality of global trade and provide more detailed findings. Motivated by this new approach and by the fact that USD is substantially used in the trade between China and the EU and the UK, this paper scrutinizes how the vehicle currency USD and the bilateral exchange rates asymmetrically affect China's trade balance with each EU country and the UK. The results of NARDL estimation indicate that the USD models outperform the bilateral exchange rate (BER) models in terms of detecting significant long-run and short-run coefficients, which confirms the usefulness of the new approach. Also, this paper finds that the USD/CNY exchange rate cannot be neglected in China's trade with the EU and the UK, which can supplement China's policies on international trade and foreign exchange management.

• 한국농공학회논문집
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• 제64권2호
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• pp.71-83
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• 2022

In this study, an indicator and assessment system for evaluating the monthly hydrological cycle was prepared using simple factors such as the landuse status of the watershed and topographic characteristics to the dynamic water balance model (DWBM) based on the Budyko framework. The parameters a1 of DWBM are introduced as hydrologic cycle indicators. An indicator estimation regression model was developed using watershed characteristics data for the introduced indicator, and an assessment system was prepared through K-means cluster analysis. The hydrological cycle assessment system developed in this study can assess the hydrological cycle with simple data such as land use, CN, and watershed slope, so it can quickly assess changes in hydrological cycle factors in the past and present. Because of this advantage is expected that the developed assessment system can predict changes in the hydrological cycle and use an auxiliary tool for policymaking.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2009년도 학술발표회 초록집
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• pp.1452-1456
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• 2009

Water related disasters frequently occur in these days due to global warming and climatic change. This give us that the trend of mal-distribution of available water resources would be increased and the environment of water resources management getting much worse. Therefore the establishment of the effective strategy should be required for water resources management urgently. In this paper the hydrological characteristics and corresponding social phenomena of the drought events in Geum river basin are inspected in depth. The word, social phenomena, means not the quantitative damage but the qualitative social influences and its main characters are analyzed by the collections of the mass media articles. This study will be helpful in prognosticating the future drought occurrence and the establishment of counterplan to them.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2011년 춘계학술대회논문집
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• pp.230-235
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• 2011

COMS (Communication, Ocean and Meteorological Satellite) is a geostationary satellite and was developed by KARI for communication, ocean and meteorological observations. COMS was tested under vacuum and very law temperature conditions in order to correlate thermal model and to verify thermal design. The test was performed by using KARI large thermal vacuum chamber. The COMS S/C thermal model was successfully correlated versus the 2 thermal balance test phases. After model correlation, temperatures deviation of all individual unit were less than $5^{\circ}C$ and global deviation and standard deviation also satisfied the requirements, less than $2^{\circ}C$ and $3^{\circ}C$. The final flight prediction was performed by using the correlated thermal model.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2004년도 학술발표회
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• pp.1326-1330
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• 2004

This study analyzes the rubber-dam of hydrologic character to be located in a Nagdong-river main stream in Dasamyeon Juggogli of the Dae-gu global city lot the river environment monitoring. The purpose of this research investigates the influence according to the rubber-dam install scientificly. A result natural disposition, prepare the gauge to matte the width of the area of the understanding and the computation of the rating which Apply is possible. Into the result of this research, $Q=898.8h^2-26126h+189886$ edge was computed to the rating. Also this study use the now rate to get for an upside expression and analysis a water balance. Through the officer to be efficient a hereafter seminar zero and processing of the data to be acquired, the supplementation so that this study can share the data to the online. High practical use of the The self-governinig body of the data and data confirmed report which loses in the trust will be achieved.

• 한국전산유체공학회지
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• 제16권3호
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• pp.59-65
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• 2011

COMS (Communication, Ocean and Meteorological Satellite) is a geostationary satellite and was developed by KARI for communication, ocean and meteorological observations. COMS was tested under vacuum and very low temperature conditions in order to correlate thermal model and to verify thermal design. The test was performed by using KARI large thermal vacuum chamber. The COMS S/C thermal model was successfully correlated versus the 2 thermal balance test phases. After model correlation, temperatures deviation of all individual units were less than $5^{\circ}C$ and global deviation and standard deviation also satisfied the requirements, less than $2^{\circ}C$ and $3^{\circ}C$. The final flight prediction was performed by using the correlated thermal model.

• 해양안보
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• 제3권1호
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• pp.73-114
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• 2021

본 연구는 현실주의의 대표적 이론인 세력균형이론을 기초로 군사력을 국가의 핵심 힘으로 전제하여 동북아시아의 힘의 분포를 살펴본다. 이전 세력균형과 군사력 수준에 관한 연구결과를 고찰하고, 그 연구한 결과를 활용하여 2020년까지 미국, 중국, 러시아, 일본, 한국과 북한의 힘의 변화를 분석하여 2030년경 안보환경을 전망하여 본다. 세력균형이론에서 국가(nation)나 국가군(a group of power) 간에 힘의 균형이 무너지면 전쟁 가능성이 높고, 그 불확실성과 불신이 높은 국제사회에서 생존과 안전을 확보하기 위하여 국가는 힘의 증강(자조, self-help)과 더불어 협력(cooperation)과 동맹(alliance)을 더욱 강화하는 행동을 한다고 본다. 동북아시아의 국가들도 자국의 군사력을 지속 증강하고 있으며, 특히 중국의 급속한 부상으로 국제 안보환경의 급격한 변화에 주변 국가들은 촉각을 세우고 경계심을 늦추지 않고 있다. 중국은 2030년대 중국 창군 100주년과 더불어 '국방 및 군현대화'를 실현하고, 2050년대 건국 100주년에 '세계일류군대건설'을 목표로 하고 있다. 그리고 미국은 국제사회의 협력과 동맹 강화 등 중국 견제에 분주하다. 미국과 중국이 패권경쟁이 진행되고 있는 상황에서 동북아시아의 안보환경과 힘의 역학관계도 서서히 변하고 있다. 세력균형이론에 기초하여 2030년 이후 동북아시아의 힘의 분포 변화와 함의를 살펴보고자 한다.