• Journal of Korean Society of Transportation
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• v.23 no.2
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• pp.117-130
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• 2005

In both deteministic user Optimal Traffic Assignment Model (UOTAM) and stochastic UOTAM, travel time, which is a major ccriterion for traffic loading over transportation network, is defined by the sum of link travel time and turn delay at intersections. In this assignment method, drivers actual route perception processes and choice behaviors, which can become main explanatory factors, are not sufficiently considered: therefore may result in biased traffic loading. Even though there have been some efforts in Stochastic UOTAM for reflecting drivers' route perception cost by assuming cumulative distribution function of link travel time, it has not been fundamental fruitions, but some trials based on the unreasonable assumptions of Probit model of truncated travel time distribution function and Logit model of independency of inter-link congestion. The critical reason why deterministic UOTAM have not been able to reflect route perception cost is that the route perception cost has each different value according to each origin, destination, and path connection the origin and destination. Therefore in order to find the optimum route between OD pair, route enumeration problem that all routes connecting an OD pair must be compared is encountered, and it is the critical reason causing computational failure because uncountable number of path may be enumerated as the scale of transportation network become bigger. The purpose of this study is to propose a method to enable UOTAM to reflect route perception cost without route enumeration between an O-D pair. For this purpose, this study defines a link as a least definition of path. Thus since each link can be treated as a path, in two links searching process of the link label based optimum path algorithm, the route enumeration between OD pair can be reduced the scale of finding optimum path to all links. The computational burden of this method is no more than link label based optimum path algorithm. Each different perception cost is embedded as a quantitative value generated by comparing the sub-path from the origin to the searching link and the searched link.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.18 no.6
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• pp.262-274
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• 2019

The purpose of this study is to estimate the minimum proportion of probe vehicles for obtaining expressway traffic information using VISSIM, a micro traffic simulation model, between Yongin IC and Yangji IC on Yeongdong Expressway. 7,200 scenarios were created for the experiment, and 40 scenarios were adopted using the Latin hypercube sampling method because it was difficult to perform all the scenarios through experiments. The reliability of the experiment was improved by adding a situation when the general situation and the accident situation exist. In the experiments, the average travel time of probe vehicles at different market penetration rates were compared with the average travel time of the entire vehicles. As a result, the minimum market penetration rate of probe vehicles for obtaining expressway traffic information was found to be 45%. In addition, it is estimated that 25% market penetration rate of probe vehicle can meet 70% of traffic situations in accident scenario.

• Journal of Korea Port Economic Association
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• v.32 no.4
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• pp.183-192
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• 2016

The purpose of this study is to analyze the choice behavior of the mode of transportation for travel from Korea to China. Discrete choice analysis is utilized to establish the factors that affect travelers' choice and to quantify the importance of these factors in transportation mode choices. The proposed choice models were constructed by using stated-preference (SP) data obtained from Chungcheongnam-do. This study also examined different choice behavior in order to capture any previously unobserved differences in the residence area. Results showed that the access time and frequency attributes are the most significant factors, while the travel time attributes are the least significant factors for travelers' choice behaviour. The insights of the results described in this research provide some practical suggestions to transportation providers for planning and strategic management endeavors in the future.

• Journal of Distribution Science
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• v.10 no.12
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• pp.19-24
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• 2012

Purpose - This paper discusses the heterogeneous fixed fleet vehicle routing problem with pick-up and delivery (HFFVRPPD), for vehicles with different capacities, fixed costs, and travel costs. Research Design, data, methodology - This paper made nine assumptions for establishing a mathematical model to describe HFFVRPPD. It established a practical mathematical model, and because of the non-deterministic polynomial-time hard (NP-hard), improved the traditional simulated annealing algorithm and tested a new algorithm using a certain scale model. Result - We calculated the minimum cost of the heterogeneous fixed fleet vehicle routing problem (HFFVRP) with a single task and, on comparing the results with the actual HFFVRP for the single task alone, observed that the total cost of HFFVRPPD reduced significantly by 46.7%. The results showed that the new algorithm provides better solutions and stability. Conclusions - This paper, by comparing the HFFVRP and HFFVRPPD results, highlights certain advantages of using HFFVRPPD in physical distribution enterprises, such as saving distribution vehicles, reducing logistics cost, and raising economic benefits.

• Proceedings of the Korea Water Resources Association Conference
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• 2005.05b
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• pp.937-942
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• 2005

It is necessary to estimate the runoff hydrograph and peak flood discharge using law of probability for synthetic flood control policy and design of hydraulic structures. Rainfall analysis is needed in the process of peak flood discharge estimation and the time distribution of a design rainfall is a very important process in the analysis. In this study, we estimate design flood for a small urban basin and a rural basin of medium scale which have different travel times. The Huff method is widely used in Korea for the time distribution of design rainfall to estimate design flood. So, we use Huff method and a conceptual method which is suggested in this study for the comparative purpose. The 100-year frequency rainfall is used to estimate design flood for each basin and the design flood is compared with the existing design flood. As the result, the design flood is overestimated $14.6m^3/sec$ by Huff method and is underestimated $70.9m^3/sec$ by a conceptual method for the rural basin. For the small urban basin, the design flood is excessively overestimated $294.65m^3/sec$ by Huff method and is overestimated $173m^3/sec$ by a conceptual method. The reason of excessive overestimation by Huff method in the small urban basin is that the increased rate of rainfall intensity according to the decrease of duration is large and the duration exceeds the time of concentration when the increased rainfall intensity is concentrated in a quartile. Therefore, we suggested a conceptual method for the time distribution of design rainfall by considering the rainless period and duration. Especially, the conceptual method might be useful for the small urban basin with short concentration time which the design flood is overestimated by Huff method.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.11 no.5
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• pp.78-88
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• 2012

AVIs on the road are installed for (1) security (2) and for traffic, and they are various managed by (1) police department, (2) local government, (3) national highway management, (4) Korean highway corporation. But although the collected data of the plate number, the travel time, the picture of the car are same, they are used in purposes of its installation because the managements are different and the data are difficult to be connected with each other. For this reason, this study is to appraise the application for creating traffic information by integrating these data, and to suggest the introduction of spatial detection system which integrated security-traffic AVI DB for the purpose of reliability improvement of center's velocity. The estimating sections of link travel information seems to be expanded, and the error rate between the center's velocity and the experimental value will be reduced if integrated DB of traffic and security AVIs is used for creating traffic information. Also, the crime prevention and arrest rate is expected to rise in the future.

• The Journal of Industrial Distribution & Business
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• v.10 no.7
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• pp.83-89
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• 2019

Purpose - It is a very important issue for the Korean tourism industry to increase tourism revenue by attracting foreign tourists. Although Japanese tourists have been an important part of the Korean tourism industry for a long time, the level of tourist satisfaction including accommodation has been at the worst compared to other foreign visitors, which strongly requires concrete solutions. Therefore, this study focuses on improving the satisfaction level of Japanese visitors in the use of accommodation, and find out the influence of the managerial response. Research design, data, and methodology - In this study, customer review and managerial response of hotels in Seoul were collected from "Rakuten Travel" which is the most representative online travel agency in Japan. As a result of collecting data from 2016 to 2018, 6,190 customer reviews and 1,241 managerial responses from 120 hotels were used for analysis. In addition, information on the properties of 120 hotels, such as the number of rooms, classification, types of hotel facilities, types of room facilities, accessibility and prices, were collected. To test the hypotheses, moderated multiple regression analysis was conducted with SPSS 22.0. Results - It was found that only 25 sites, 20.8% of the total 120 sites, were implementing managerial response and average response rate was 66.42% among them. As a result of examining the main effects of the hotel attributes on the ratings, accessibility and price are confirmed as effective variables. We also found that the response rate has a significant moderate effect in both the accessibility and price. In other words, there was a significant difference in the influence of accessibility and price on the ratings depending on the response rate. Also, it was confirmed that the response rate is not a pure moderator variable but a quasi moderator variable. Overall, the evidences partially supported the hypothesis. Conclusion - It was possible to provide important suggestions to the hotel managers who were concerned about managing tourist satisfaction with accessibility problems. It was found that the accessibility problem could be overcome by increasing the response rate. It was also confirmed that high ratings can be more effectively achieved for high priced hotels by increasing the response rate.

• Journal of Korean Society of Rural Planning
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• v.18 no.3
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• pp.13-24
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• 2012

This study aimed to investigate the images that affect general travel behavior and satisfaction of eco-tourists of Section seven of Jeju Olle-gil and to give eco-tourists preferred images to newly constructed eco-tour sections. Adjectives were selected to evaluate images, and for analysis, a survey was carried out with 132 persons who have toured 7 section of Jeju Olle-gil. On this survey, basic travel type, overall satisfaction, image before and after experience, age, gender, satisfaction level and accompanying type were inquired. 81(61.4%) knew section 7 of Jeju Olle-gil 'in advance', and 58(39.1%), which takes up the largest portion in this question, came to choose section 7 by a word of mouth. 95(71.9%) answered that they stayed 2 nights and 3 days, and 55(41.7%) answered that they stayed at a pension as accommodation. As for accompanying type, 34(25.7%) answered they accompanied family and relatives. As for the decision of visit, 60(45.5%) replied that they decided one month prior to the visit. And as for the purpose of visit, 63 (33.8%) replied they visited to appreciate nature. The adjectives that demonstrate overall satisfaction and significance level of the tourists were 'placid', 'refreshing', 'living', 'mountainous' and 'green'. As for the satisfaction level, people were satisfied with its environment, cleanliness level and direction boards. The types of section preferred by the tourists were clay pavements, followed by sand-masa soil mixture pavement and wooden deck pavement. 'Oidolgae' section was selected as the representative section, and 10:00a.m.~12:00p.m. was preferred as visiting time. And it is also proved that people were positive in appointing photo zones.

• Journal of the Korean Home Economics Association
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• v.40 no.12
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• pp.199-216
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• 2002

The purpose of this research is to study the efficiency of the Internet market, not provided to consumers by the existing traditional market. This research examines whether consumers properly understand the efficiency of the Internet market. The result from consumers perception on the efficiencies in the two market are as follows. First, consumers perceived the traditional market as having more product alternatives compared to the Internet market. Second, consumers perceived that the Internet market was more efficient in price dispersion and price change Third, the Internet market was considered more efficient in searching and travel time, and in the search cost. Finally, the traditional market was considered as a better provider of the information about product function, feature, reality, usage and service compared to the Internet market. On the contrary, the Internet market turned out to be more effective in providing product information, price information and trading information compared to the traditional market. Therefore consumers perceived the traditional market of having more information.

• Proceedings of the KSR Conference
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• 2002.05a
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• pp.303-311
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• 2002

A first evaluation of the possibilities of high speed trains in conventional railway in Korea have been investigated. The radius of curvature was considered the major problem with high-speed trains in Korea. If KNR(Korea National railway) likes to increase the speed, is then whether KNR shall construct straigthen the track or develop a train that can reduce travel time in curves The research concerns structural design of train car-body is to reduce heavy stress concentration. Using 3D solid modeling, Finite Element analysis and shape optimization combined with powerful postprocessing, graphical display and animation to achieve complete and accurate design and performance will be carried out further project Main purpose of this project is to provide korean tilting train car body's conceptional design. Based on first year research results, the design of car-body will be performed by train manufacture.