• KSCE Journal of Civil and Environmental Engineering Research
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• v.28 no.5D
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• pp.695-703
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• 2008

China water market has huge potential for increased use of BOT mode and one of the most attractive markets of doing business. However, the current China water BOT market shows that many foreign companies are retreating from the market while Chinese water companies fast growing. From the view no domestic companies have track records in China BOT water market, the research identified twenty market access barriers in terms of construction laws, regulations, BOT-related policy and the recent market situation. These are evaluated based on interview results with 10 professionals direct or indirect having a China water BOT experience. All the factors are found to be highly influential to foreign company's decision on the market participation. Among those, no fixed return policy and low water price, difficulty in water price adjustment and approval, and no government guarantees, all directly related to the project viability and under the control of government, were the most critical factors, implying government's role is the key in increasing the market competition by attracting more foreign participation on the market. In addition, new construction law regulating foreign EPC contractor's construction work, namely Decree 113, and requirement of applying competitive bidding in selecting EPC contractor in a BOT project are also considered signigicant barriers on foreign participation, which contradicts international norm and therefore necessitates an adjustment on current decision process in domestic companies.

• Structural Engineering and Mechanics
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• v.85 no.5
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• pp.655-664
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• 2023

Reinforced concrete (RC) shear wall structures are one of the most widely used structural systems to resist seismic loading all around the world. Although there have been several efforts to provide conceptually simple procedures to reasonably assess the seismic demands of structures over recent decades, it seems that lesser effort has been put on a number of structural forms such as RC shear wall structures. Therefore, this study aims to represent a simple linear response spectrum-based method which can acceptably predict the nonlinear displacements of a non-ductile RC shear wall structure subjected to an individual ground motion record. An effective period and an equivalent damping ratio are introduced as the dynamic characteristics of an equivalent linear SDOF system relevant to the main structure. By applying the fundamental mode participation factor of the original MDOF structure to the linear spectral response of the equivalent SDOF system, an acceptable estimation of the nonlinear displacement response is obtained. Subsequently, the accuracy of the proposed method is evaluated by comparison with another approximate method which is based on linear response spectrum. Results show that the proposed method has better estimations for maximum nonlinear responses and is more utilizable and applicable than the other one.

• Journal of Navigation and Port Research
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• v.44 no.1
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• pp.32-43
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• 2020

The purpose of this study was to extract and evaluate the factors to improve the quality of shipping logistics platform suggested as an alternative to the stagnant shipping logistics industry. For this, we selected factors through previous research and expert interviews, and conducted surveys on carriers, forwarders, shippers, and platform operators with experience using shipping logistics platforms. As a method of analysis, quality evaluation of the shipping logistics platform was conducted using IPA (Importance-Performance Analysis). The results of this study are as follows "Competitiveness of services provided", "Connectivity with other transportation mode", "Competitiveness of freight", "Transparency of freight", and "Stability of booking space". For the shipping logistics platform to be activated in the future, priority should be given to focusing on these factors. This study has academic significance for establishing configuration function of shipping logistics platform and deriving evaluation factor. Additionally it is an industrial significance for suggesting strategies to improve users' participation in the shipping logistics platform.

• Journal of Korean Society of Transportation
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• v.24 no.5 s.91
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• pp.89-108
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• 2006

Korea has been entering the ageing society as the population of age over 65 shared over 7% since the year 2000. The ageing society needs to have transportation facility considering elderly people's travel behavior. This study aims to understand the elderly people's travel behavior using recent data in Korea. The activity schedule approach begins with travel outcomes are part of an activitv scheduling decision. For tho?e approach. used discrete choice models (especially. Nested Logit Model) to address the basic modeling problem capturing decision interaction among the many choice dimensions of the immense activity schedule choice set The day activity schedule is viewed as a sot of tours and at-home activity episodes tied togather with overarching day activity pattern using the Seoul Metropolitan Area Transportation Survey data, which was conducted in June, 2002. Decisions about a specific tour in the schedule are conditioned by the choice of day activity pattern. The day activity scheduling model estimated in this study consists of tours interrelated in a day activity pattern. The day activity pattern model represents the basic decision of activity participation and priorities and places each activity in a configuration of tours and at-home episodes. Each pattern alternative is defined by the primary activity of the day, whether the primary activity occurs at home or away, and the type of tour for the primary activity. In travel mode choice of the elderly and non-workers, especially, travel cost was found to be important in understanding interpersonal variations in mode choice behavior though, travel time was found to be less important factor in choosing travel mode. In addition, although, generally, the elderly was likely to choose transit mode, private mode was preferred for the elderly over 75 years old owing to weakened physical health for such things as going up and down of stairs. Therefore. as entering the ageing society, transit mode should be invested heavily in transportation facility Planning tor improving elderly transportation service. Although the model has not yet been validated in before-and-after prediction studies. this study gives strong evidence of its behavioral soundness, current practicality. and potential for improving reliability of transportation Projects superior to those of the best existing systems in Korea.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.15 no.5
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• pp.1-11
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• 2016

The purpose of this study is to contribute the use of special taxi for the transportation vulnerable such as elderly and pregnant woman in terms of improving transportation mobility and extending social participation. We analyzed the DB users of STS system operating in Suwon, and surveyed the preference statement. Specifically, we have built transportation mode choice models for the elderly and pregnant woman, and then we drew the activating STS plan by comparing influence factors for each model. Based on the results of the study, 23% of STS user was the elderly people and pregnant women, 31% of user was for hospital passage purpose, and short-haul passage within 2 ~ 5km was 70% level of the passage. According to preference survey results between STS and Bus, fare was the highest impact factor in the mode choices for the elderly, and the participants who are older and car owners have been found to prefer the special taxi. For the pregnant woman, travel time and fare were the main influence factors of choices, and it was discovered that they preferred the special taxi when they are car owners and trips was frequented. Also, if the fare of special taxi is about 70% of the regular taxi fare, The share rates of Special Taxi comparing to bus for the elderly and pregnant woman are analyzed to be 51.1% and 63.6% each. Therefore, the adjustment of the fare would be effective to encourage the use of the special taxi. The results of this study can be used as a basis for establishing the rational fare structure of the special taxi.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.32 no.1
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• pp.17-27
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• 2019

In this paper, we study the applicability of Tuned Mass Damper(TMD) to improve seismic performance of piping system under earthquake loading. For this purpose, a mode analysis of the target pipeline is performed, and TMD installation locations are selected as important modes with relatively large mass participation ratio in each direction. In order to design the TMD at selected positions, each corresponding mode is replaced with a SDOF damped model, and accordingly the corresponding pipeline is converted into a 2-DOF system by considering the TMD as a SDOF damped model. Then, optimal design values of the TMD, which can minimize the dynamic amplification factor of the transformed 2-DOF system, are derived through GA optimization method. The proposed TMD design values are applied to the pipeline numerical model to analyze seismic performance with and without TMD installation. As a result of numerical analyses, it is confirmed that the directional acceleration responses, the maximum normal stresses and directional reaction forces of the pipeline system are reduced, quite a lot. The results of this study are expected to be used as basic information with respect to the improvement of the seismic performance of the piping system in the future.