• 품질경영학회지
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• 제36권2호
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• pp.20-27
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• 2008

Tolerance design has been identified as an important research area and a number of models have been proposed in the literature. This paper investigates the effect of limited capacity on tolerance design for products with nominal-the-best type (N-type) quality characteristics. The model is developed under the assumption that the reprocessed and nonreprocessed items are produced by the same manufacturing process and therefore their quality characteristics are identically and independently distributed. Profit models are constructed which involve four price/cost components; selling price, cost incurred by imperfect quality, reprocessing and quality inspection costs. Methods of finding the optimal tolerance limits are presented, and a numerical example is given. Sensitivity analyses are also performed to study the effect of a process standard deviation on this model.

• 한국경영과학회:학술대회논문집
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• 한국경영과학회/대한산업공학회 2003년도 춘계공동학술대회
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• pp.381-385
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• 2003

We consider the bandwidth parking problem arising from telecommunication networks The problem is to determine the set of calls to be routed and an assignment or them to the paths in arc capacitated network. The objective is to maximize profit. We formulate the problem as an integer programming and propose an algorithm to solve it. Column generation technique to solve the linear programming relxation is proposed with two types of columns in addition, to obtain an optimum integer solution, we consider a new branching strategy. Computational experiments show that the algorithm gives option at solutions within reasonably small time limits.

• Journal of Electrical Engineering and Technology
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• 제12권3호
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• pp.1038-1045
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• 2017

To address mounting concerns over global warming, the Paris Agreement was reached in December 2015, which aims to limit the increase in global average temperature. South Korea has set a highly ambitious target to reduce emissions and submitted an Intended Nationally Determined Contribution (INDC). Based on the INDC, we investigated the impact of limiting carbon emissions on the power system and the electricity market in Korea. Through detailed simulations on assumed plausible scenarios, this work highlights a) the effects of different carbon emission targets on the annual carbon emission volumes, generation costs, and carbon price; b) the generation mix changes induced by carbon emission limits; and c) the difference in system marginal price and payments for generator owners that carbon emission constraint creates in electricity markets under three different pricing rules.

• 대한전기학회논문지:전력기술부문A
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• 제52권7호
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• pp.429-436
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• 2003

This paper presents a new approach for evaluating the transmission marginal loss factors (MLFs) considering the reactive power. Generally, MLFs are represented as the sensitivity of transmission losses, which is computed from the change of the generation at reference bus by the change of the load at the arbitrary bus-i. The conventional evaluation method for MLFs uses the only H matrix, which is a part of jacobian matrix. Therefore, the MLFs computed by the existing method, don't consider the effect of the reactive power, although the transmission losses are a function of the reactive power as well as the active power. To compensate the limits of the existing method for evaluating MLFs, the power factor at the bus-i is introduced for reflecting the effect of the reactive power in the evaluation method of the MLFs. Also, MLFs calculated by the developed method are applied to energy spot markets to reflect the impacts of reactive power. This method is tested with the sample system with 5-bus, and analyzed how much MLFs have an effect on the bidding/offer price, market clearing price(MCP), and settlement in the competitive energy spot market. This paper compared the results of MLFs calculated by the existing and proposed method for the IEEE 14-bus system, and the KEPCO system.

• 에너지공학
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• 제11권4호
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• pp.291-298
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• 2002

본 연구에서는 전력산업 구조개편 환경에서 최적조류계산에 의한 전력조류 및 한계계수를 해석할 수 있는 실용적인 방법론을 제시한다. 먼저, 유용한 한계계수의 산정을 위해 전압제약, 선로과부하 제약, 발전 출력 제약 등의 각종 계통제약이 고려된 연료비 및 송전손실 최소화의 비선형 최적화 문제가 정식화되고 비선형 주·쌍대 내점법에 의한 해법이 제시된다. 또한, 최적조류계산에 의해 계산된 감도에 기초하여 한계가격 및 한계송전손실의 산정방법이 제시된다. 특히, 경쟁적 전력시장에서 송전손실에 관한 가격을 반영하기 위해 한계손실계수의 해석법이 제안된다. 본 연구의 결과를 IEEE RTS 24모선에 적용하여 전력시장가격의 해석에 대한 그 유용성을 검증하였다.

• Journal of the Korean Data Analysis Society
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• 제20권6호
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• pp.2759-2769
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• 2018

The behavioral finance view on the existence of asset pricing anomalies is based on two factors: investors' sentiment and limits to arbitrage. This paper tries to examine the effect of investors' sentiment on the stock price in the Korean stock market. In order to measure investors' sentiment, we constructed the sentiment index using principal component of five sentiment variables. By using sentiment index as an additional independent variable to three risk factors, impacts of the sentiment index on individual stocks and 25 portfolios sorted by BM-size are examined. Main results found are as follows: 1) not only all three risk factors show positive impacts on the return of individual stock, but also the sentiment index has a positive impact. SI alone explains 15% of individual return variation. 2) among four independent variables, the most important factor turned out to be the market risk factor and investors' sentiment has better explanatory power on stock price than the size effect. 3) after controlling the market risk factor, the coefficient of the sentiment index for the smallest size and highest book/market value portfolios is significantly positive. 4) all the coefficients of the sentiment index for 25 portfolios sorted by BM-size have significant positive value after controlling size or (and) value.

• 대한토목학회논문집
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• 제32권4D호
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• pp.357-366
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• 2012

기존의 품셈과 지방세법은 건설중장비가 수 년에 걸친 감가상각 대상임에도 불구하고, 물가지수를 제대로 반영하지 못하고 있다. 이에 본 연구에서는, 법인세법과 지방세법 및 기업회계기준서를 분석하여 국내 감가상각제도의 특징과 상각방법을 정리하여 제시하였고, 경제성 이론이 반영된 건설중장비 자본회수계수를 제시하였고, 정액법과 정률법을 사용하여 표준품셈을 기준으로 한 감가상각과 세법을 기준으로 한 감가상각 사례를 제시하였다. 개선방안으로는, 건설중장비의 자발적 사용기간 신청제도와 현행제도와의 관계를 설명하고 도입을 제안하였으며, 국내물가지수를 기초로 월단위 기계경비 감가상각율표를 개발하여 제공하였으며, 그 적용방안을 예시하였다. 또한, 제안한 방안의 장점과 단점을 분석하여 연구의 적용한계와 차후 개선방향도 제시해 보았다. 본 연구를 통해 품셈과 세법에 보다 합리적이고 객관적인 현실성을 반영할 수 있을 것으로 판단된다.

• 한국의류학회지
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• 제35권1호
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• pp.37-50
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• 2011

This study analyzed the content of special selling events in internet shopping malls to establish academic standards for special selling events as tools for sales promotions and to suggest systematic guidelines for marketers designing special selling events. Based on a content analysis, the titles of special selling events from four internet shopping malls selling women's apparel were analyzed. A total of 692 titles were analyzed. The results are as follow. First, the contents categories of special selling events could be classified into two groups such as 'theme' and 'tool'. Season, product characteristics, style, advice/information, brand, annual/social events, and marketing events were the main content categories that came under the 'theme' group; in addition, the price benefit, free offers, product mix, and marketing technique were the main content categories that came under the 'tool' group. Each main content category was subdivided into several segment content categories. Second, most of the titles were composed of more than two segment content categories that involved various information and benefits; however, the portion of titles composed of only theme related content categories or only tool related content categories was substantial. Furthermore, the theme related content categories were more than the tool related content categories. Third, the usage frequencies of the contents categories were analyzed. The upcoming season, single brand, sale/discount, item/material/color, special price/lowest price, and period/time/quantity limits were the segment content categories that held a high rank. Forth, most of the factors that evoked the unplanned purchases of consumers were related to the content categories of special sale events.

• 한국기술혁신학회:학술대회논문집
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• 한국기술혁신학회 2001년도 추계학술대회
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• pp.169-186
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• 2001

신제품 개발과정에 대한 전반적인 흐름에 대해서는 기존의 연구가 다양하게 이루어져왔으나 구체적으로 어떠한 방법론이나 도구를 사용하여 시행하는가에 대해서는 논의가 미미하였다. 따라서 본 연구에서는 신제품 개발시 시장에서 생존가능한 제품속성과 가격을 결정하는 방법으로서 계량경제학적 헤도닉 방법론을 대체할 DEA 모델을 제안하고자 한다. 제품속성과 가격이 이루는 곡면이 유연하게 형성되도록 QC-DEA를 사용하고 거기에 제품속성에 대한 소비자의 선호체계를 반영하기 위하여 AR을 도입하여 AR-QC DEA라는 모델을 만들었다. AR-QC DEA는 모수적 방법론의 한계를 극복할 뿐만 아니라 제품마다 다른 잠재가격을 제시하기 때문에 신제품 개발시 제품속성과 가격의 조합에 대해 많은 정보를 제공해 줄 수 있고 또한 그렇게 만들어진 신제품이 과연 시장에서 생존할 수 있는가를 손쉽게 모의테스트 할 수 있다. 마지막으로 노트북 컴퓨터 제품에 대한 AR-QC DEA의 실증연구를 통해 AR-QC DEA가 충분한 현실설명력을 가짐을 볼 수 있다.

• 한국경제지리학회지
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• 제16권1호
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• pp.71-85
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• 2013

본 연구는 개별 상업용 건물들을 중심으로 주변지역에 위치한 상업용 건물들과 주거지 개발패턴이 해당 건물가격에 미치는 영향을 고찰함으로써 물리적 도시공간구조가 부동산시장, 특히 상업용 부동산시장에 미치는 영향을 분석하고자 한다. 이를 위해 GIS 소프트웨어를 이용하여 용도간 근접성을 체크하였다. 연구 결과, 용도혼합이 오프스 건물가격에 긍정적인 영향을 미치는 것으로 나타나, 뉴 어버니즘에서 강조하는 복합용도개발을 통해 지속가능한 커뮤니티를 만들 수 있다는 가능성을 확인하였다. GIS기술을 이용하여 기존 연구들이 경제사회변수와 같은 대리변수를 사용했던 한계를 극복하고, 공간구조를 보다 정밀하게 측정할 수 있었다. 또한 토지이용에 따른 2차원분석이 아니라, 각 건물의 높이를 계산하여 3차원 분석을 함으로써 공간의 이용과 함께 밀도까지 고려한 방법론을 사용한 의의가 있다.