• Proceedings of the Korea Society for Simulation Conference
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• 1999.10a
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• pp.121-126
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• 1999

지능망은 소비자 또는 가입자의 다양한 욕구를 신속하고도 효과적으로 제공하며 동시에 새로운 서비스에 대한 수요가 있을 경우에 이에 쉽게 대처할 수 있는 차세대 통신망이다. FEP-BEP 구조를 갖는 (N+1) 형식의 지능망 서비스 시스템에서의 서비스에 대한 부하균형 방법으로 각 SCP-BEP 시스템별로 서비스의 종류에 따라서 부하를 할당하는 방식이 있으며, 이를 국내 통신회사에서 실제로 적용하고 있다. 이러한 방식의 장점은 부하균형을 동적으로 할당할 수 있고, 신규 서비스의 등록이나 기존 서비스의 갱신시에 기존에 제공하던 서비스에 대한 호에 미치는 영향을 최소화 할 수 있다는데 있다. 본 논문에서는 SCP-BEP에 제공하는 서비스별로 할당하는 부하량에 따른 시스템의 성능추이를 시뮬레이션 기법에 의하여 추적하고 그 결과에 대하여 기술한다.

• Proceedings of the KIEE Conference
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• 2007.07a
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• pp.838-839
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• 2007

전력산업의 시장구조는 과점형태의 불완전 경쟁의 구조로 해석하는 것이 일반적이다. 또한 전기의 물리적 특성상 송전선로에서는 전력손실이 발생하게 되는데, 본 논문은 과점시장 모델로서 쿠르노(Cournot)모델을 사용하여 손실을 포함한 내쉬 균형점을 해석한다. 지역별 한계가격(Locational Marginal Price ; LMP)와는 달리 계통한계가격(System Marginal Price ; SMP)는 손실에 대한 가격신호를 시장에 반영하기 어렵기 때문에 손실과 함께 한계송전손실계수(Marginal Loss Factor ; MLF)를 적용하여 균형상태의 시장거래가치를 비교분석한다.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.12
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• pp.6353-6363
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• 2013

This study examined the factors associated with recurrent falls among the community-dwelling elderly. The participants were 329 community-dwelling elderly. The data was collected from February 5, 2010 to February 14, 2010. Over the past 1 year, 14.3% of the 329 participants fall once, and 4.0% experienced recurrent falls. There was a significant difference among the non fallers, single faller and recurrent fallers with regard to the static balance(F=5.86, p=.003), dynamic balance(F=24.32, p<.001), risk of fall(F=9.94, p<.001) and compliance of prevention behavior related to falls(F=3.09, p=.047). The analysis results for the correlation between variables showed that the number of falls had a negative effect on the knee flexors muscular strength(r=-.15, p=.008), static balance(r=-.16, p=.004) and compliance of prevention behavior related to falls(r=-.12, p=.030) and a positive affect for the dynamic balance(r=.26, p<.001), depression(r=.13, p=.019) and risk of falls(r=.30, p<.001). The variables explained 36.0% of the variants in the occurrence of recurrent falls. Therefore, an effective recurrent fall prevention program should focus on multiple risk factor intervention.

• Journal of the Korea Society of Computer and Information
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• v.10 no.2 s.34
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• pp.205-213
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• 2005

A balanced regional development has a great meaning of economics in the fact that the People could enjoy the equal level of lift everywhere in the country by reducing the income disparity and economic productivity between regions, however as the our country was given Preponderance of economical power and development to the metropolitan area centering around Seoul due to a factor of politics, social structure as well as a national economic policy centering around a rapid economic growth, the unbalanced regional growth gave rise to great hindrance to a national development. Especially, the unbalanced 9rowth between regions gave rise to a sense of alienation to a citizen in a special region as well as a distortion of an effective resources distribution. therefore it was deepen a social discord to hinder the unity of the people due to always coming to involve social ,political affairs. The major contents of this study is to clarify relations between the economic growth and the balanced regional development to form a concept of a national development, and this thesis made disparities in population and convenient facilities between regions through change of convenient facilities of life, economic growth, and population between regions an analytic object to concrete the studies. Also, this thesis made a whole countw land an analytic object of spatial sphere. and it made a unit of ten years when the five-year economic development plan was achieved from the year 1962 to 2001 an otject of the time range of studies.

• Proceedings of the Korean Society for Emotion and Sensibility Conference
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• 2002.11a
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• pp.233-244
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• 2002

The purpose of this study is to assess the ability of balance control in moving surround using head mount device and force platform and to examine the clinical usefulness of COP parameters. Fifteen patients with stroke and healthy persons were participated. COP parameters were obtained as total path distance, frequency of anterior-posterior and medial-lateral component by FFT analysis, weight-spectrum analysis in the two different conditions; (1) in comfortable standing with opened or closed eyes, (2) in virtual moving surround delivered using HMD to four different moving pattern. In virtual moving surround setting, moving pattern was composed of close-far, superior-inferior tilting(pitch), right-left tilting(roll) and horizontal rotation(yaw) movement. In all parameters, the reliebility of COP analysis system was significantly high. Also, the construct validity compared between fifteen patients with stroke and normal persons was excellent in virtual moving surround condition(p

• Environmental and Resource Economics Review
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• v.20 no.4
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• pp.827-858
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• 2011

In Korea, various environmentally harmful subsidies are granted in agriculture, fishery, energy, electricity, transportation, steel and shipbuilding industry. Examples include tax-exempt fuel for agriculture & fishery, VAT- exemption for briquette & anthracite, temporary subsidy for fuel, production stabilizing subsidy for coal mining, subsidy for briquette. Korea's yearly total subsidy in energy area is about 5,291 billion won, among them is 4,870 billion won. To reduce air pollutants and to mitigate climate change, Korea has to review the phase-out of environmentally harmful subsidies and the phase-in of environment-friendly subsidy. The reduction or removal of environmentally harmful subsidies will enhance economic efficiency and bring about environmental benefits. Economic efficiency means less use of inputs, which reduces environmental cost and improves social benefits. This paper applies the Shoven and Whalley's model to the Korean economy and analyzes the general equilibrium incidence effects of reforming environmentally harmful subsidies in the energy and electricity in Korea. We consider several counterfactual scenarios in which current environmentally harmful subsidies are reduced or abolished, compare them with the reference case in the economy, and evaluated the change in efficiency costs and distributional incidence of tax reforms related to subsidies.

• KDI Journal of Economic Policy
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• v.35 no.3
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• pp.1-38
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• 2013

This study investigates the welfare implications of BTL projects using a general equilibrium model with the public sector and public-private partnerships. We show that when the government is not allowed to run budget deficits but private firms is able to overcome the financial constraint, BTL projects performed by public-private partnerships (PPPs) could be a good alternative and improve the welfare of the model economy. This paper quantitatively investigates excessive expansion of PPP projects and several alternatives to retrieve welfare losses caused by such an expansion. Assuming that future rents of BTL projects are not taken into account, we find the welfare losses up to 20 percent relative to conventional government projects. Finally, we show that it would be possible to reduce the losses by transforming the fully depreciated capital stock of the government projects into much smaller new PPP projects.

• Journal of the Korea Computer Industry Society
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• v.2 no.2
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• pp.203-210
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• 2001

To estimate relational models and test the theoretical hypotheses of binary tree search algorithms, we built binary search trees with random permutations of n (number of nodes) distinct numbers, which ranged from three to seven. Probabilities for building binary search trees corresponding to each possible height and balance factor were estimated. Regression models with variables of number of nodes, height, and average number of comparisons were estimated and the theorem of O(1g(n)) was accepted experimentally by a Lack of Test procedure. Analysis of Variance model was applied to compare the average number of comparisons with three groups by height and balance factor of the trees to test theoretical hypotheses of a binary search tree performance statistically.

• The Korean Journal of Financial Management
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• v.17 no.2
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• pp.175-209
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• 2000

본 연구는 프로그램매매가 주가지수 선물시장 및 현물 주식시장의 수익률 변동성에 미치는 효과에 대해서 일중 수익률 및 프로그램매매자료를 이용하여 분석을 시도하였다. 실증분석을 통해서 관찰된 결과를 살펴보면 대부분 선진국 시장에서 보고된 결과와 일치하였다. 우선 프로그램매매가 증가할수록 현물 주식시장에서의 변동성은 증대하는 것으로 나타났으나 선물시장에서는 그러한 일관성 있는 관계를 발견하지 못하였다. 프로그램매매 발동 직후 선물 및 현물시장의 수익률은 반전현상을 나타냈으며 특히 현물시장의 가격변화가 선물시장에 비해서 큰 것으로 관찰되었다. 그러나 이러한 선물시장과 현물시장에 있어서의 가격반전 현상이 시장 유동성에 미치는 경제적 영향은 선물만기일과 같이 특정시간대에 프로그램매매가 집중되지 않는 한 경미한 것으로 판단되었다. 프로그램매매 특히 차익거래는 선물 가격과 현물 가격간의 균형 관계가 일시적인 수급상황에 따라 이발될 경우 이를 다시 균형 상태로 회복시켜 줌으로써 시장의 효율성을 증대시키는 주요한 연결통로로서의 역할을 수행한다. 특히 두 시장간의 균형 상태는 선물 시장보다는 현물 주식시장에서의 활발한 매매 활동을 통하여 이루어짐을 알 수 있었다. 결론적으로 국내시장에서 차익거래는 시장의 위험을 증대시키는 부정적인 측면보다는 시장의 효율성을 증진시키는 긍정적인 순기능이 많은 것으로 관찰되었다.

• KDI Journal of Economic Policy
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• v.5 no.4
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• pp.83-107
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• 1983