• Environmental and Resource Economics Review
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• v.17 no.4
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• pp.875-901
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• 2008

This article estimates the economic values of changes in water quality of the Paldang Watershed by using the Choice Experiment (CE). The conditional logit model estimation results show that a small improvement in water quality from the 'status quo' level to the level of 'very good' increases average household's monthly utility by 3,157 Won, whereas a water quality degradation down to the 'normal' level gives rise to an increase in the monthly average utility by 9,649 Won. The corresponding social gain and loss of water quality changes to the Metropolitan Area were thus estimated about 285 billion Won and 872 billion Won, respectively. This article seems meaningful in that it resorts to the new water ecosystem classification criteria and indices that are respondent-friendly. They help a CE study like this to overcome one of its critical weakness that the number and contents of attributes of a CE study can quickly add to the information overload problem, especially where the environmental good under investigation is hard for ordinary respondents to understand.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2006.11a
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• pp.599-617
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• 2006

A network model and a Genetic Algorithm(GA) is proposed to solve the simultaneous estimation of the trip distribution and traffic assignment from traffic counts in the congested networks in a logit-based Stochastic User Equilibrium (SUE). The model is formulated as a problem of minimizing the non-linear objective functions with the linear constraints. In the model, the flow-conservation constraints of the network are utilized to restrict the solution space and to force the link flows meet the traffic counts. The objective of the model is to minimize the discrepancies between the link flows satisfying the constraints of flow-conservation, trip production from origin, trip attraction to destination and traffic counts at observed links and the link flows estimated through the traffic assignment using the path flow estimator in the legit-based SUE. In the proposed GA, a chromosome is defined as a vector representing a set of Origin-Destination Matrix (ODM), link flows and travel-cost coefficient. Each chromosome is evaluated from the corresponding discrepancy, and the population of the chromosome is evolved by the concurrent simplex crossover and random mutation. To maintain the feasibility of solutions, a bounded vector shipment is applied during the crossover and mutation.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.10
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• pp.4830-4836
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• 2013

This research was launched as an attempt to help create a new value-added product called "Green Jujube Chip." To accomplish the objectives, consumers value by attributes of Green Jujube Chip should be estimated. We used Choice Experiment for analysis, which we used to arrive at pricing of specialty jujube chips based on the conditional logit model. As a result, MWTP were estimated at 1333 Won/unit for Mid-size Company Product, 1752 Won/unit for Large Company Product, 1703 Won/unit for University Affiliation, 350 Won/unit for packing unit, 548 Won/unit for rating the raw fruit, 1,322 Won/unit for HACCP, and 1,166 Won/unit for ISO22000. The consumer's WTP for Green Juju Chip, associated with the university-brand recognition, was higher than a product produced by a mid-sized company but lower than a product by a large company. Given how the consumers regard the university-brand product as a specialty item, it is necessary to create value-added products that meet such high expectation. Therefore, we recommend the producers to acquire HACCP Food Safety Certification and the value-added product has used the highest quality raw fruit.

• Journal of Labour Economics
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• v.27 no.1
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• pp.135-164
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• 2004

Using the data from the KLIPS, this study categorizes unemployed women into the four mutually exclusive groups according to the two criteria (whether to have intention to work and the comparison of reservation and market wages), and investigates factors affecting the status of the unemployment of women. Heckman's sample selection regression and multinomial logit are applied for the estimation. The major results are: the proportion of unemployed women who do not have intension to work or whose reservation wages are greater than expected market wages is about 50%, and the proportion of unemployed women who have intension to work or whose reservation wages are less than expected market wages is about 50%; second, human capital, burden of child raising and household production, household economic status, the variables related to work experience are found to be the factors affecting unemployment status of women.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.33 no.4
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• pp.1559-1569
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• 2013

this study is to deduct the difference between regional and urban commercial trips by analyzing the characteristics of the regional and urban truck movements. To achieve this, we investigated the relation between the number of truck trips and various truck generation attributes such as truck attributes, origin and destination attributes, and commodity type using ordered logit models, which are separately estimated for regional and urban truck movements using truck diary data of Korea Transport Database (KTDB). According to the estimation results, regional and urban truck movements have different characteristics in truck attributes, origin and destination attributes and commodity type. Especially, the number of regional trucks trips increased as origin and destination are manufactural area and as the total value of products of industrial area in origin and destination increase.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.20 no.1
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• pp.26-33
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• 2012

Competition between air transportation and railways has grown fiercer in major countries around the world with the rise of high-speed railways. In South Korea, air passenger travel has been rapidly decreasing since the initial launch of the Seoul-Pusan KTX line in 2004 and second opening that followed in 2010. Further expansion of the high-speed railway is expected. At present, research efforts to verify the validity of constructing an underwater express railway tunnel between Ho-nam and Jeju Island are taking place. Considering the possible high speed railway connection between Seoul and Jeju Island, this thesis has analyzed the choice behavior of existing passengers of the major and low-cost carriers. For this, Stated Preference (SP) research has been performed for three variables, including fare, travel time and the number of runs, to estimate the substitution rate of each of the three variables. Binomial Logit Model has been estimated with the obtained data. The estimation of the model has found that airline passengers of major and low-cost carriers are willing to pay approximately 7,200 KRW and 5,000 KRW, respectively, to reduce travel time by one hour. If the number of runs in one day increases, it has been estimated that the passengers are willing to pay additional fares of about 390 KRW and 30 KRW, respectively. On the other hand, the substitution rate between the number of runs and the travel time was found to be somewhat insignificant. If the construction of the Seoul-Jeju line progresses in the future, this study could be used as preliminary data for determining fares, travel time and the number of runs.

• Journal of Korean Society of Transportation
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• v.31 no.5
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• pp.48-59
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• 2013

Normally the benefits concerned in the feasibility study for highway constructions are travel time saving, vehicle operation cost, etc. which can be calculated using the simulation tool(EMME3). However, there must be extra benefits of driving amenity improvement that drivers can perceive through decreasing driving fatigue and improving driving comfortability. In this study, the definition of driving amenity was established and a method of estimation for the benefit of driving amenity improvement was developed. Highway type (urban/rural highway) and highway density was considered to estimate the driving amenity. And Double-bounded Dichotomous Choice among Contingent Valuation Method(CVM) was applied to survey the willingness-to-pay of drivers when highway density decreases. Finally the value of driving amenity was estimated using the results of survey and logit medel. As the existing highway density is high, willingness-to-pay increases in both urban and rural highways. Even though the changing rates of highway density are same, willingness-to-pay is different based on the existing highway density.

• Journal of agriculture & life science
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• v.44 no.3
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• pp.89-97
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• 2010

In the contingent valuation method (CVM) survey, we employed double-bounded discrete choice (DBDC) question to investigate the willingness to pay (WTP). The estimation results for the bivariate logit model show that respondents are willing to pay 329,256 won per year. The model with covariate variables suggests that the covariate effects help describe behavioral or preference tendencies. Double-bounded models increase efficiency over single dichotomous choice models, because the answers yes-no or no-yes yield clear bounds on WTP.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.55 no.1
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• pp.1-6
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• 2019

The annual production of silver croaker (Argyrosomus argentatus) in Korean towed fishing gears has been increased in recent five years. In 2017, the annual production of silver croaker in metric ton was increased 99.2% compared to 2013. However, the research for silver croaker has been focused on ecology in Korea. There has not been enough research in terms of fishing gears. Therefore, the research for retention probability for towed gears was conducted on covered codend method from June, 2016 to July, 2018. During the experiments, the total catch of silver croaker was 1,563. The geometry of the experimental trawl gear was controlled by trawl monitoring system; net height was 3.3 m, distance of trawldoors was 59.8 m and distance of wing net was 17.3 m. The selection curve for silver croaker was estimated by a logit model. The analysis was applied with the confidence interval to reduce uncertainty of the estimation. The $l_{50}$ was 13.87 cm and its selection range was 2.71 cm. P-value was estimated at 0.99. The mesh size for silver croaker in towed gears needs to be adjusted by considering its minimum maturity length, stakeholder's interests and fisheries regulations.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.22 no.6
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• pp.66-76
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• 2023

The government recently implemented policies to improve transportation for the disabled passengers. On the other hand, metropolitan public transport still lacks adequate services for these individuals. Many new cities lack urban rail lines and focus on high-floor buses for expansion. Wheelchair users can only access to double-decker low-floor seat express buses for intercity travel. This study examined the necessity and rationale for introducing low-floor seat buses by estimating the user's willingness to pay through a contingent valuation method. Two methods for eliciting the willingness to pay were adopted: open-ended and dichotomous choice questions. The binomial logit model was used to estimate the willingness to pay. The results indicated that the general public is willing to pay an additional 126.7 Korean won, while the disabled passengers are willing to pay an additional 117.5 Korean won. When translated into annual economic benefits, this amounts to approximately 35 billion Korean won.