• Journal of Korea Water Resources Association
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• v.46 no.9
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• pp.933-946
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• 2013

The quantitative analysis of evapotranspiration (ET) is a key component in hydrological studies and the establishment of water resources planning. Generally, the quantitative analysis of ET is performed by the estimation method of potential or reference ET based on meteorological factors such as air temperature, wind speed, etc. Hargreaves equation is one of empirical methods for reference ET using air temperature data. In this study, in order to estimate more exact reference ET considering climatological characteristics in Korea, parameter regionalization of Hargreaves equation is carried out. Firstly, modified Hargreaves equation is presented after the analysis of the relationship between solar radiation and temperature. Secondly, parameter ($K_{ET}$) optimization of Hargreaves equation is performed using Penman-Monteith method and modified equation at 71 weather stations. Lastly, the equation for calculating $K_{ET}$ using temperature data is proposed and verified. As a result, reference ET from original Hargreaves equation is overestimated or underestimated compared with Penman-Monteith method. But modified equation in this study is more accurate in the climatic conditions of Korea. In addition, the applicability of the equation between $K_{ET}$ and temperature is confirmed.

• Journal of the military operations research society of Korea
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• v.35 no.3
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• pp.119-138
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• 2009

Work and family are two major fields of one's life. In the past, the role of each gender has been separated, and there was no conflict between two fields. However, the increasing rate of working woman and the mode of social change that the male has also responsible of caring family and individuals has more interested in their personal life make consider these two fields as a whole. A number of studies have shown that OCB contribute in important ways to organizational functioning and performance. Whereas citizenship behavior may affect organizations in several positive ways, it is also possible that engaging in such behaviors could have negative consequences for the employees who do so. There may be other personal costs such as work-family conflict that accrue to individuals who engage in high levels of citizenship behavior. The purpose of this study is to investigate the moderating effect of the SOC strategy and Family Friendly Atmosphere on the negative effects of OCB on Work-Family Conflict. Questionnaire data were collected from 590 in different jobs. According to the result of empirical analysis, it proved that the more OCB effect on the more Work-Family Conflict. it also was found that the SOC strategy and Family Friendly Atmosphere moderate the relation between OCB and Work-Family Conflict. At the end of the paper, theoretical and managerial implications of this study, future research directions are discussed.

• Journal of the Korea Institute of Building Construction
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• v.17 no.5
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• pp.473-481
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• 2017

With the barracks modernization project, the Ministry of National Defense has been operating 60 projects of the 75 that have been announced. It was difficult to investigate and analyze the data in the past because data could not be obtained while it was much easier to do that since data can be obtained from private companies. With the aim of increasing the usability of the facilities, the objective of this study is to present a reasonable alternative for repair and maintenance costs by investigating and analyzing the budget and the actual expenses of repair and maintenance of military facilities for the past 3 to 5 years, and then identifying the problems with these. To accomplish this, a theoretical review of previous studies and legal grounds related to repair and maintenance costs was performed, and data on the estimates and the actual expenses data used in BTL projects carried out by private companies were analyzed. First, one of the problems was that there are some items omitted, including consumables, and these items should be included in order to secure their budget. Second, in terms of the items for divided payments, two improvements had been presented: a short-term payment plan for the operation period of 3 to 5 years and a long-term payment plan for an additional and complemented period other than the operation period. The repair and maintenance costs should be further studied at the point of time in a future when the actual data on the costs and operation period of military facilities can be secured. This study is expected to serve as empirical data that will form the basis for a reasonable calculation of the construction cost for military facilities.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.12
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• pp.8-14
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• 2019

A drop structure, one of the representative river-crossing structures, is constructed to stabilize a riverbed. On the other hand, the structure interrupts the continuity of the river and causes the destruction of the hydro-ecological environment. Therefore, laboratory experiments of a natural type of drop structure with low differences were performed, and the empirical formula of a local scour hole is proposed. Four experimental flow rates were tested for various types of the drop structure models with 28 test cases. Based on the scour test, it was confirmed that the maximum scour depth occurs rather than the result of applying the previously proposed scour depth formulae. Correlation analysis of the major factors of scour hole at the downstream of the drop structure revealed a strong correlation between the upstream flow characteristics, drop structure height, and total crossing length of the drop model. In addition, the depth and length estimation formula of the maximum scour hole were proposed using the dimensionless variables and validated. In the future, it is also expected that more accurate scour prediction and calculation can be derived by conducting experimental studies and numerical analysis considering the various bed materials and flow conditions.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.12
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• pp.190-199
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• 2019

South Korea has achieved impressive economic growth relatively quickly by focusing on export-driven policies and economies of scale in the process of industrialization. As the country's economic development policy focused on large corporations, however, a power and wealth imbalance developed between SMEs and large corporations. The purpose of this study is to clarify this issue academically and more clearly through theoretical studies and empirical analysis in order to resolve these imbalances and improve the positive relationship between SMEs and large corporations. To this end, a survey was conducted from December 17, 2018 to January 28, 2019, and a total of 378 questionnaires collected from corporate workers were used for the final analysis. The hypotheses confirmed by the study results were as following. First, the factors directly affecting the competitor's orientation were the trust, entrepreneurship, and innovation capability of the entrepreneurial characteristics. Second, when the characteristics of the company were examined from the perspective of cooperative performance, only the innovation capacity factor had a positive effect. Third, the competitor orientation showed a positive effect on cooperative performance. Fourth, competitor orientation had a statistically significant mediating effect on the relationship between trust, entrepreneurship, innovation capability, and cooperative performance.

• The Korean Journal of Financial Management
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• v.21 no.1
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• pp.1-32
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• 2004

This paper investigates the stock price and the volume behavior on the ex-dividend day using the December fiscal year firms listed on the Korea Stock Exchange from 1998 to 2000. Using the samples of voluntarily preannounced dividend-raying firms prior to the end of fiscal you, this study corrects the major limitations on previous studies -Kim, S. (1997) and Kim, S. (2003)- which were based on the perfect foresight assumption for firms' upcoming dividends. Also, this paper examines the information content of dividend more properly, since the preannounced date for the upcoming dividend payment is employed for the first time as the event date. Empirical results show that the announcement effects of cash and/or stock dividend is significant around the event date. The ex-dividend day stock returns are negative as expected for the samples of voluntarily preannounced cash dividend-paying firms.

• Environmental and Resource Economics Review
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• v.13 no.3
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• pp.337-366
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• 2004

Contingent Valuation Method (CVM), as non-market valuation approach, has been criticized on that respondents may not realistically reflect their budget constraints in answering willingness to pay (WTP) for hypothetical CV questions. This paper empirically estimates the income calibration factor associated with CV responses through combining travel cost method and contingent valuation method in a utility-theoretic framework. The joint model of recreation demand function and contingent WTP function was applied to an important case study on the Man Kyoung River system, whose water quality is at issue because of the Sae Alan Kum reclamation project. Relevant economic variables such as price, income and water quality had significant influence as anticipated by the economic theory. Equally important, the income calibration factor was not significantly different from one, suggesting that the systematic discrepancies of CV responses relative to the actual behavior was not detected at least in terms of budget exaggeration. Overall, this study supports the notion that carefully designed CVM studies can provide informative data on individuals' willingness to pay for environmental quality changes.

• Environmental and Resource Economics Review
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• v.25 no.2
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• pp.199-228
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• 2016

This study investigates the effects of economic factors and forest environments on rural residential area development in seven north central states of the U.S. by focusing on the relative importance of not only economic factors but also forest environments by forest type as core drivers of residential development. An empirical model of locations and magnitudes of population changes since 1950 in the north central region is first constructed, and then a panel model with fixed effects for counties is used to explain population growth by age group over time at the county level. Then a set of three equations is estimated for three major age groups, and a cross-sectional model is estimated for the last time period that regresses county-level environmental amenity variables on fixed effects coefficients for counties. Finally, an equation explaining changes in rural housing density is estimated. The results imply that immigrant age is a key factor influencing the choice of the place of residence and that the effects of environmental amenity factors on population growth and subsequent housing development in a county vary according to the age group.

• Journal of the Korean association of regional geographers
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• v.7 no.4
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• pp.120-145
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• 2001

Environmental risk is one of major risks in contemporary society which is often conceptualized in terms of 'risk society'. The crisis which retains such environmental risk can be characterized by 'technical hazards', rather than natural hazards in traditional societies, because of potentiality of technical control over its generation and managing process. Environmental crisis tends to be recurred due to certain limitations of response of both government and civil society. Moreover, it can be argued that generation of environmental crisis and limitations of its managing process are inherent in problematic structures in contemporary society, especially in its 4 basic elements and their characters; that is, capitalist market economy which promotes increasing profits and decreasing cost; bureaucratic representative politics which has brought about concentration of power and evasion of responsibility, instrumental science and technology which leads to blind belief on scientific knowledge and its uncertainty; and finally individualistic way of life with exclusive and passive response to crisis. This paper aims to consider the generation and managing process of environmental crisis in terms of these 4 basic elements, with comparative studies on empirical cases of the water crisis by Phenol pollution in Taegu in 1991 and the water crisis by parasites contamination in Sydney in 1998.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.38 no.2
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• pp.337-347
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• 2018

The government has been operating residential improvement projects through the "Act on the Maintenance and Improvement of Urban Areas and Dwelling Conditions for Residents" as a type of a remedial measure for deteriorated residential areas. However, in recent years, the residential improvement projects have experienced difficulties due to the effects of various factors including the slowdown in economic growth. After observing the depression in a number of projects, various studies have been carried out to investigate the causality and improve the promotion of the residential improvement projects. In the trend of research, this study aims to analyze the effects of land and building characteristics on the improvement projects of Busan Metropolitan City. The dependent variables of the study represent different phases of improvement project as specified in the "Act on the Maintenance and Improvement of Urban Areas and Dwelling Conditions for Residents". The independent variables represent land and building characteristics which refer to the criteria used in the designation process of maintenance area according to the act. The empirical analysis uses the ordered logit model. The results from the analysis suggest that geographical condition, factors related to the number of union members, factors related to the parcel price and condition of a location have impact on the promotion of the improvement project. The results of the analysis show that majority of the factors are related to the economic feasibility of the projects. Residential improvement project is a part of urban planning projects that rehabilitates deteriorated residential environment, and it is closely associated with the quality of life of public. Accordingly, we hope that such projects are reasonable and take effective approach to those with urgent needs rather than to focus on profitability. Also, potential administrative and economical loss should be avoided by taking necessary planning measures in advance.