• 한국철도학회논문집
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• 제9권6호
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• pp.772-777
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• 2006

Three-dimensional numerical study is performed for the flow analysis around the rolling stock with square cross section (Mugungwha train model). The height (H) of rolling stock is considered as the characteristic length and the total length of rolling stock is 40 which correspond to 1/2 unit of rolling stock. The gap between the surface and rolling stock is 0.17H which is average value. The relative velocity between the surface and rolling stock is assumed to be zero and Re=10,000 based on the characteristic length. Low Re ${\kappa}-{\epsilon}$[15] is employed for the calculation of turbulence which resolve all the way to the solid surface (laminar sub-layer). Large flow separation occurred at the front head of train and a pair of vortex is generated on both top and side of rolling stock. The behavior of vortices on the top of the rolling stock is believed to affect the performance of the pantograph which should be intensively investigated. The difference between the high pressure in the front stagnation region of train and the low pressure in the rear separated region causes a large pressure drag. A large pair or vortex are generated in the rear of train and the size of vortex is increased more than the size of cross section of train.

• 융합경영연구
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• 제4권3호
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• pp.1-6
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• 2016

The purpose of the present study is to investigate the relationship between Managerial overconfidence and vehicle and parts manufacturing firm value of the listed companies on the Tehran Stock Exchange (TSE). The population includes 25 firms selected through systematic sampling. The data is collected from the audited financial statements of the firms provided by TSE's website from 2010 to 2015. In this study the variables, Overconfidence based on earning per share (OEPS), Overconfidence based on capital cost (OCC) has been used to investigate Managerial overconfidence. The results of multiple linear regression analysis show that there is a significant relationship between Overconfidence based on earning per share (OEPS) and firm value. In addition, there is a significant relationship between Overconfidence based on capital cost (OCC) The present research examined the relationship between Managerial overconfidence and vehicle and parts manufacturing firm value of the listed in Tehran Stock Exchange. The results of multivariate regression accepted two the hypotheses of the research. There is a significant relationship between Managerial overconfidence and vehicle and parts manufacturing firm value.

• Asia Marketing Journal
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• 제16권1호
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• pp.169-193
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• 2014

The earlier studies have verified that brand values have significant impact on financial values such as stock return and stock price to justify marketing costs for brand building. Except for Mizik and Jacobson (2008), however, little research has addressed what kinds of brand components composing brand values have a significant relationship with financial values. As a follow-up research of Mizik and Jacobson (2008), this research focuses on what kinds of relationships exist between the unanticipated change of each brand asset component and stock return, one of the financial values. The authors selected six brand asset components from the Korea-Brand Power Index(K-BPI) data in which 'Top of Mind,' 'Unaided Awareness,' and 'Aided Awareness' are brand awareness measures and 'Image,' 'Purchase Intention,' and 'Preference' are brand loyalty measures. Out of those six brand components, they found that unanticipated changes of 'Top of Mind,' 'Unaided Awareness,' 'Image,' and 'Preference' have significantly positive effect on unexpected stock return change. Therefore, they conclude that these four brand asset components provide incremental information in explaining unanticipated stock return.

• Ocean and Polar Research
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• 제40권4호
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• pp.237-247
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• 2018

This study aims to estimate optimal harvests, fishing efforts, and stock levels of hairtail harvested by the large pair bottom trawl, the large otter trawl, the large purse seine, the offshore long line, and the offshore angling fisheries by using the surplus production models and the current value Hamiltonian method. Processes of this study are as follows. First of all, this study estimates the standardized fishing efforts regarding the harvesting of the hairtail by the above five fishing gears based on the general linear model developed by Gavaris. Secondly, this study estimates environmental carrying capacity (k), intrinsic growth rate (r), and catchability coefficient (q) by applying the Clarke Yoshimoto Pooley (CY&P) model among various surplus production models. Thirdly, this study estimates the optimal harvests, fishing efforts, and stock levels regarding the hairtail by the current value Hamiltonian method, including the average landing price, the average unit cost, and the social discount rate. Finally, this study attempts a sensitivity analysis to figure out changes in optimal harvests, fishing efforts, and stock levels due to changes in the average landing price and the average unit cost. As results induced by the current value Hamiltonian method, the optimal harvests, fishing efforts, and stock levels regarding the hairtail caught by several fishing gears were estimated as 33,133 tons, 901,080 horse power, and 79,877 tons, respectively. In addition, from the results of the sensitivity analysis, first of all, if the average landing price of the hairtail constantly increases, the optimal harvests of it increase at a decreasing rate, and then harvests finally slightly decrease as a result of decreases in stock levels. Secondly, if the average unit cost of fishing efforts continuously increases, the optimal fishing efforts decreases, but optimal stock levels increase. Optimal harvests start climbing and then decrease continuously due to increases in the average unit cost. In summary, this study suggests that the optimal harvests (33,133 tons) were larger than actual harvests (25,133 tons), but the optimal fishing efforts (901,080 horse power) were much less than estimated standardized fishing efforts (1,277,284 horse power), corresponding to the average of the recent three years (2014-2016). This result implies that the hairtail has been inefficiently harvested and recently overfished due to excessive fishing efforts. Efficient management and conservation policies on stock levels need to be urgently implemented. Some appropriate strategies would be to include the hairtail in the Korean TAC species or to extend the closed fishing season for this species.

• 산경연구논집
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• 제8권5호
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• pp.87-93
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• 2017

Purpose - This paper investigates whether managerial overconfidence is associated with firm-specific crash risk. Overconfidence leads managers to overestimate the returns of their investment projects, and misperceive negative net present value projects as value creating. They even use voluntary disclosures to convey their optimistic beliefs about the firms' long-term prospects to the stock market. Thus, the overconfidence bias can lead to managerial bad news hoarding behavior. When bad news accumulates and crosses some tipping point, it will come out all at once, resulting in a stock price crash. Research design, data and methodology - 7,385 firm-years used for the main analysis are from the KIS Value database between 2006 and 2013. This database covers KOSPI-listed and KOSDAQ-listed firms in Korea. The proxy for overconfidence is based on excess investment in assets. A residual from the regression of total asset growth on sales growth run by industry-year is used as an independent variable. If a firm has at least one crash week during a year, it is referred to as a high crash risk firm. The dependant variable is a dummy variable that equals 1 if a firm is a high crash risk firm, and zero otherwise. After explaining the relationship between managerial overconfidence and crash risk, the total sample was divided into two sub-samples; chaebol firms and non-chaebol firms. The relation between how I overconfidence and crash risk varies with business group affiliation was investigated. Results - The results showed that managerial overconfidence is positively related to crash risk. Specifically, the coefficient of OVERC is significantly positive, supporting the prediction. The results are strong and robust in non-chaebol firms. Conclusions - The results show that firms with overconfident managers are likely to experience stock price crashes. This study is related to past literature that examines the impact of managerial overconfidence on the stock market. This study contributes to the literature by examining whether overconfidence can explain a firm's future crashes.

• 산업경영시스템학회지
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• 제15권26호
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• pp.111-117
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• 1992

In the stock marketing. investor needs speedy and accurate decision making for the investment. A stock exchange index provides the important index of the early of 1993 in Korea using Fuzzy Delphi Method(F. D. M) which is widely used to a mid and long range forecasting in decision making problem. In the Fuzzy Delphi method, considerably qualified experts an first requested to give their opinion seperately and without intercommunication. The forecasting data of experts consist of Triangular Fuzzy Number (T.F.N) which represents the pessimistic, moderate, and optimistic forecast of a stock exchange index. A statistical analysis and dissemblance index are then made of these subject data. These new information are then transmitted to the experts once again, and the process of reestimation is continued until the process converges to a reasonable stable forecast of stock exchange index. The goal of this research is to forecast the stock exchange index using F.D.M. in which subjective data of experts are transformed into quasi -objective data index by some statistical analysis and fuzzy operations. (a) A long range forecasting problem must be considered as an uncertain but not random problem. The direct use of fuzzy numbers and fuzzy methods seems to be more compatible and well suited. (b) The experts use their individual competency and subjectivity and this is the very reason why we propose the use of fuzzy concepts. (c) If you ask an expert the following question: Consider the forecasting of the price index of stocks in the near future. This experts wi11 certainly be more comfortable giving an answer to this question using three types of values: the maximum value, the proper value, and the minimum value rather than an answer in terms of the probability.

• 재무관리연구
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• 제20권1호
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• pp.61-92
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• 2003

스톡옵션 부여 공시가 비정상적인 양(+)의 초과수익률을 가져온다는 선행 연구의 연장선상에서, 본 연구에서는 스톡옵션 부여 공시가 야기하는 초과수익률이 시간 및 부여횟수에 따라 변하는가를 검증해 보았다. 스톡옵션 도입 초기부터 스톡옵션 부여가 보편화된 시기까지에 대해 스톡옵션 부여공시에 따른 주가반응이 동일한가를 검증한 결과, 2000년 이후에는 스톡옵션 부여공시가 뉴스로서 가지는 의미가 점차 약해짐을 발견했다. 또한, 한 기업이 여러 차례에 걸쳐 스톡옵션을 부여할 경우, 부여횟수가 증가함에 따라 초과수익률이 점차 감소함을 발견했다. 이는 기업의 스톡옵션 부여가 보다 보편화될수록 스톡옵션 부여공시가 가지는 뉴스로서의 긍정적인 영향이 상대적으로 감소됨을 의미한다. 주식시장에서 보다 많은 수의 기업이 스톡옵션을 부여할수록, 또 한 기업이 여러 차례에 걸쳐 스톡옵션을 부여할수록, 투자자들은 기업의 스톡옵션 부여가 기업가치 증대에 미치는 영향이 상대적으로 적어질 것이라 기대함을 시사한다.

• 재무관리연구
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• 제24권4호
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• pp.163-199
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• 2007

이 논문은 시장에 두 종류의 투자자가 존재하고 이들의 정보 분석 능력과 정보 획득 시점이 서로 다르다면 시장에서 가격이 어떻게 형성되고 변화하는 가를 연구하려고 한다. 시장에는 대규모 자금을 관리하면서 전문적으로 정보를 분석하고 투자하는 기관투자자와 소규모 자금을 투자하는 개인투자자가 있다. 기관투자자들이 개인투자자에 비하여 정보 분석 능력이 뛰어나고 정보 획득시점도 빠르다고 가정한다. 위 가정으로부터 이 논문은 시장에서 주식 가격이 단기에서는 가격지속현상을 보이고 장기에서는 가격역전현상을 보이는 것을 설명할 수 있다. 단기에서 가격지속 현상이 나타나는 것은 개인투자자에 비하여 정보를 먼저 획득한 기관투자자들이 주식을 거래하여 이미 가격이 변화하였는데 뒤늦게 정보를 획득한 개인투자자들이 계속하여 거래함으로써 가격이 단기적으로 같은 방향으로 움직이게 된다. 장기적인 가격역전 현상은 기업의 가치에 대하여 정확한 정보를 가지고 있지 못한 개인투자자들이 새로운 정보에 대하여 지나치게 민감하게 반응하여 주식가격이 기업의 내재가치 이상으로 변화하게 되고 시간이 지남에 따라 주식 가격이 기업의 내재가치로 회귀하기 때문에 나타난다. 단기적인 가격지속과 장기적인 가격역전 현상이 나타나는 주된 원인이 새로운 정보에 대한 개인투자자의 지연반응과 정보부족에 있기 때문에 이 논문은 개인투자자의 비율은 높은 주식일수록 이러한 현상이 더 크게 나타남을 보였다. 기관투자자들이 주식을 매입하면 다음 시점의 가격은 상승하고 이들이 주식을 매도하면 다음 시점의 가격은 하락한다. 반대로 개인투자자들이 주식을 매입하면 다음 시점의 가격은 하락하고 이들이 주식을 매도하면 다음 시점의 가격은 상승하게 된다.

• 경영과학
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• 제30권1호
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• pp.43-58
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• 2013

Although analysis of charts, which used in stock trading by distinguishing standardized patterns in the movements of stock prices, is simple and easy to use, there can be problems stemming from specific patterns being distinguished as a result of the subjective perspectives of analysts. In accordance with such problems, through the method of template pattern matching, 4 trend reversal patterns were designed and the fitness of the patterns were quantitatively measured. In cases when a stock is purchased when the template pattern fitness value is within a certain range and held for at least 20-days, the average return ratio was analyzed to be higher-with the difference being statistically significant-than the average return ratio attained from trading a stock according to the same method per the Efficient Market Hypothesis. From the results of stock trades of 2 domestic corporations to which the values of the 4 patterns had been applied based on the 4 strategies, it was possible to ascertain differences in the strategy- and pattern-dependent return ratios. Through this study, along with presenting the exceptions for the Efficient Market Hypothesis in stock trading, the fitness level of quantitative chart patterns was measured and the theoretical basis for application of such fitness level was proposed.

• 한국조리학회지
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• 제19권3호
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• pp.209-217
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• 2013

본 연구에서는 소스나 수프 등의 기본재료가 되는 홍합 육수를 제조함에 있어서 홍합의 각종 영양 성분을 적절하게 이용하여 홍합 육수를 만들고자 하였다. 수분함량은 가열시간이 증가함에 따라 유의적(p < 0.05)으로 낮아졌다. 색도측정 결과, L값은 MS1(35.48)이 가장 높았고, a값도 MS1(-2.39)이 가장 높았으며, b값은 MS5(-9.49)가 가장 높았다. pH는 MS5가 6.56으로 가장 낮아 가열시간이 증가 시 시료 간의 유의적(p < 0.001)인 차이를 보이며 낮아졌다. 당도는 MS3이 $4.03^{\circ}Brix$로 가장 높았고, MS1이 $3.37^{\circ}Brix$로 가장 낮았다. 염도는 MS1이 0.71%로 가장 낮았고, 가열시간이 증가 시 시료간의의 유의적인(p < 0.001) 차이를 보이며 염도가 높아졌다. 홍합육수의 특성차이검사 결과, 육수의 외관, 투명도, 비린냄새, 비린맛, 짠맛은 가열시간 증가 시 강하게 평가되었다. 감칠맛은 MS4가 4.33으로 가장 강하게 평가되었다. 홍합육수의 기호도 검사 결과, 맛, 전체적인 기호도 항목에서는 MS3이 가장 좋게 평가되었다. 이상의 결과로 볼 때, 가열시간 증가로 홍합육수의 기호도가 대체적으로 좋게 평가되었으며, 홍합육수 제조 시 가열시간이 15분일 때 기호도가 상승되는 것을 알 수 있었다.