• Journal of Korean Society of Transportation
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• v.29 no.1
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• pp.81-93
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• 2011

This research deals with the multi-modal continuous network design problem to resolve the transportation policy problems for constructing and operating transportation facilities with considering the mutual decision-making process between transportation operator and user in the multi-modal network. Particularly, in the consideration of changes in travel pattern between transport modes due to the changes in transportation policy, road network for passenger car and transit network for public transportation are considered together. In the development of network design model, more rational Stackelberg equilibrium(cooperative game) rather than more general Nash equilibrium(non-cooperative game) approach is used and sensitivity analysis considering transport mode is used. A multi-modal continuous network design model in this study is developed for the arbitrary continuous network design parameters(${\epsilon},\hat{\epsilon},p$) of transportation policy decisions. As examples of application and evaluation for these design parameters, the developed model is applied to calculate 1)the optimal capacity of road link in the road transport policy, 2)the optimal frequency of transit line in public transport policy and 3)the optimal modal split in transport modal share policy.

• Land and Housing Review
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• v.5 no.4
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• pp.225-234
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• 2014

Because of their nature as public facilities, demands that former military facilities be utilized for the public welfare are increasing, thereby leading to an increase in cases in which these military facilities are reestablished as parks. Cases in which former military bases were reestablished as public parks were analyzed; as a result, several implications were derived. First, the objectives of public park projects should be examined from the perspective of the concept of urban regeneration and regional revitalization. Moreover, it is necessary that profits are yielded and that regional identity and history are reproduced through reusing existing facilities as much as possible rather than entirely remodeling former military sites. As parks become larger in size, bases should be reorganized into complexes rather than single facilities or programs. It is also necessary that parks be established in stages considering the enormous expenses required for building public parks. Consequently, because the special characteristics of military facilities can lead to insufficient on-site investigation in the process of establishing parks, thereby incurring a vast amount of costs for design adjustment and contamination disposal, this should be considered in advance. A method of delegating the development rights to partial sites to private businesses and supplementing the costs of park establishment and maintenance with development benefits should be examined. In addition, given that there are various interests and stakes in former military bases, a method of operating a public-private cooperative decision-making organization during project execution should be considered. Finally, policies related to urban parks need to be improved in order to raise funds, expand profitable businesses, facilitate social services and sponsorship, and encourage the participation of trusts and non-profit organizations in park operation and management.

• Journal of Korea Spatial Information System Society
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• v.3 no.1 s.5
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• pp.27-36
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• 2001

The 4S represents four systems that are commonly related to spatial information: GIS, GNSS, SIIS, ITS. The 4S technology that integrates the four systems gets more and more interests recently. In this paper, we adopt component paradigm to 4S system, apply it to the disaster control field, and design a system based on component architecture. There are many application areas to which the 4S technology can be applied. but the disaster control system is one of the most typical fields. We apply 4S technology to the disaster control fields, including fire, flood, and typhoon. Because of the characteristics of disaster control system that handles large-volume map data, component-based 4S system will take considerable effects on the improvement of disaster control works. The core functions that are common to all disaster control fields are included in 4S kernel component because of the consideration of time performance. Remaining non-common functions are implemented as separate components named as work-specific components. In our suggested system, a vehicle named as 4S-Van collects real-time information on the spot of disaster and sends image and location information to control center via wireless transmission. The control center analyzes the information together with its own spatial database or map, which was not possible in the conventional disaster control works. The control center can get desired information by sending a request of re-transmission to 4S-Van. Such method of real-time transmission supported by on-the-spot information makes the current situation judgment, decision making, and order issuance more exact, effective, and timely. The suggested system and method are expected to bring remarkable improvement on disaster control works.

• The Journal of Korean Obstetrics and Gynecology
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• v.19 no.2
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• pp.240-260
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• 2006

Purpose : The objective of this study is to serve guidelines for the investigation and management of uterine myomas with KM therapies. Methods : English-language articles from PubMed and Korean-language articles from the database of the journal of oriental gynecology were reviewed from 2000 to 2005, using the key words 'uterine myoma', 'uterine leiomyoma', 'fibroid', 'uterine artery embolization', 'endometrial ablation', 'myomectomy', and jagungguenjong(子宮筋腫)'. Results and Limits : The areas of clinical practices considered in formulating this guideline are assessment, KM therapies, medical treatments, myolysis, selective artery occlusion, endometrial ablation and surgical therapies including myomectomy and hysterectomy. Implementation of this guideline would optimize the decision-making process of women with uterine myomas and further investigation or therapy of their KM doctors. But we don't have abundant evidences of clinical trials of uterine myoma treated with KM therapy, though we treat or manage that with every-day clinical practices. Moreover cultural gaps between Korea and other western countries make many differences in the attitude to surgical therapies, especially hysterectomy. So it is very difficult to compare W therapies with other therapies. Moreover it is much difficult to estimate cost-effectiveness and benefit of those therapies in QOL. Conclusions : The majority of uterine myoma is asymptomatic and will not require any intervention or further investigation. But unmarried women who wish to marry and get pregnant want to find safe therapy for their asymptomatic uterine myomas. In that case, most of the patients prefer non-surgical therapy to surgical therapy. So KM herbal medicinal therapy is a good alternative method for those patients. For the symptomatic myomas, hysterectomy offers a definitive solution. However, it is not the best solution for women who wish to preserve their uterus. So KM therapy is a good alternative for them. But the predicted benefits of alternative therapies including KM therapy must be carefully weighed against the Possible risks of these therapies. To improve the quality of life of both women with asymptomatic and symptomatic myomas, selecting and treating patients should be done carefully. Moreover, the effect of KM therapy has to evaluated, comparing the possible situation without treatment and the benefit of constant treatment as a health-care system.

• Environmental and Resource Economics Review
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• v.29 no.2
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• pp.219-246
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• 2020

From the Phase II (2018~2020) of K-ETS, the offset credit from 'CDM projects that domestic companies and others have carried out in foreign countries' can be used in the K-ETS. As a result, stakeholders in the K-ETS market are actively developing overseas CDM projects, such as the 'high-efficiency cook stove project'. which can secure a large amount of credits while marginal cost is relatively low. This paper develops the investment decision-making model of offset project for the 'high-efficiency cook stove project' using the real option approach. Under the uncertainty of the emission allowance price, the optimal investment threshold (p^⁎) is derived and sensitivity analysis is conducted. As a result, in the standard scenario (PoA-S), the optimal investment threshold is 29,054won/ton, which is lower than the stock price (p^⁎_spot). However, allocation entities are not only economics in the CDM project, but also CDM risk factors such as non-renewable biomass ratio, cook stove replacement ratio, equity ratio with host country, investment period and submission limitation of emission allowance. In addition, offset project developers will be able to derive the optimal investment threshold for each business stage and use it for economic feasibility checks.

• Quality Improvement in Health Care
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• v.9 no.2
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• pp.116-133
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• 2002

Background : It is very common in Korea to take care of non-acute patients in an acute setting, due to the lack of long-term facilities. Long term hospitalization increase medical expenses and decreases the bed utilization, which can affect the urgent and emergent admissions, and eventually jeopardize the hospital financially. In this study, strategies for effective transfers to the lower levels of care, and to decrease the length of stay were presented by surveying and analyzing the patient's knowledge of the transfer needs, and the willingness to transfer those whose hospital length of stay was more than 30days. Method : The survey is subject to a group of 251 patients who have been hospitalized over 30 days in a general hospital in Seoul. Excluding those that were in the Intensive Care Unit and psychiatric ward, 214 in-patients were used as participants. They were surveyed from April 9, 2002 to April 17, 2002. One hundred and thirty seven out of 214 were responded which made the response rate 64%. Data were analyzed by SAS and SPSS. Result : Multi-variable Logistic Regression Analysis showed a significant effect in medical expenses, knowledge of referral system and the information of the receiving hospital. The financial burden in medical expenses made the patient 10.7 times more willing to be transferred, knowledge of the referral system made them 5 times more willing to be transferred, and the information of receiving hospital makes 6.5 times more willing to be transferred. Reasons for willing to be transferred to a lower level of care were the phase of physical therapy, the distance from home, the attending physician's advice and being unable to be treated as an out patient. Reasons for refusing to be transferred were the following. The attending physician's competency, not being ready to be discharged, not trusting the receiving hospital's competency due to the lack of information, or never hearing about the referring system by the attending physician. Conclusion : Based on this, strategies for the effective transfer to the lower levels of care were suggested. It is desirable for the attending physician to be actively involved by making an effort to explain the transfer need, and referring to the Healthcare Coordinating Center, which can help the patient make the right decision. Nationwide networking for the referral system is the another key factor that may need to be suggested as an alternative to decrease the medical expenses. Collaborating with the Home Health Agency for the early discharge planning and the Social Service Department for financial aid are also needed. It is recommended that the hospital should expedite the transfer process by prioritizing the cost and the information as medical expenses, knowledge of referring system and the information of the receiving hospital, are the most important factors to the willingness to transfer to a lower level of care.

• Journal of Navigation and Port Research
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• v.40 no.1
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• pp.35-41
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• 2016

Port congestion has been recognized as one of the critical factors for port service competitiveness and port selection criteria. However, congestion ratio, the congestion index currently used by Korea, plays a very limited role in shipping companies' and shippers' selection of port and port authorities' decision making regarding port management and development. This is mainly due to the fact that this ratio is only calculated as the ratio of the number of vessels by each port. Therefore, this study aims to measure service level related to vessel entry and departure in Korea ports by evaluating waiting ratio(WR) according to terminals and vessel types. The results demonstrate that the waiting ratio of containerships and non-containerships is less than 4% and 15% respectively, which satisfies the reasonable level suggested by the UNCTAD and OECD. Port of Pohang is revealed to have the highest WR of 57% and among the terminals, No. 1 Terminal of the Shinhang area has the highest WR. In terms of ship types, WR of Steel Product Carrier is highest, followed by General Cargo Ship and Bulk Carrier at the Pohang Shinhang area. In addition to WR, berth occupancy ratio as well as the number and time of waiting vessels can be utilized to evaluate service level by ports and terminals from port users' perspective, and furthermore, to improve the port management and development policy for port managers or authorities.

• Spatial Information Research
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• v.9 no.2
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• pp.291-307
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• 2001

In today's environmental engineering practice, many technologies such as GIS have been adopted to analyze chemical and biological process in water bodies and pollutants movements on the land surface. However, the linkage between spatially represented land surface pollutants and the in-stream processes has been relatively weak. This lack of continuity needs to develop a method in order to link the spatially-based pollutant source characterization with the water quality modeling. The objective of this thesis was to develop a two-way(forward and backward) link between ArcView GIS software and the USEPA water quality model, WASP5. This thesis includes a literature review, the determination of the point source and non-point source loadings from WASP5 modeling, and the linkage of a GIS with WASP5 model. The GIS and model linkage includes pre-processing of the input data within a GIS to provide necessary information for running a model in the forms of external input files. The model results has been post-processed and stored in the GIS database to be reviewed in a user defined form such as a chart, or a table. The interface developed from this study would provide efficient environment to support the easier decision making form water quality management.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.26 no.6
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• pp.599-609
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• 2008

Development of computer and electronic technology leads innovative progress in spatial informatics and successful commercialization. Geospatial information technology plays an important role in decision making in various applications. However, information display media are two-dimensional plane that limits visual perception. Understanding human visual processing mechanism to percept stereo vision makes possible to implement three-dimensional stereo image display. This paper proposes on-the-fly stereo image generation methods that are involved with various exterior and camera parameters including exposure station, viewing direction, image size, overlap and focal length. Collinearity equations and parameters related with stereo viewing conditions were solved to generate realisitc stereo imagery. In addition stereo flying simulation scenery was generated with different viewing locations and directions. The stereo viewing is based on the parallax principle of two veiwing locations. This study implemented anaglyphic stereogram, polarization and lenticular stereo display methods. Existing display technology has limitation to provide visual information of three-dimensional and dynamic nature of the real world because the 3D spatial information is projected into 2D plane. Therefore, stereo display methods developed in this study improves geospatial information and applications of GIS by realistic stereo visualization.

• Journal of Intelligence and Information Systems
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• v.14 no.1
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• pp.117-129
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• 2008

The cost-based scheduling work has been done in both the Operations Research (OR) and Artificial Intelligence (AI) literature. To deal with more realistic problems, AI-based heuristic scheduling approach with non-regular performance measures has been studied. However, there has been little research effort to develop a full inter-job cost propagation algorithm (CPA) for different jobs having multiple downstream and upstream activities. Without such a CPA, decision-making in scheduling heuristics relies upon local, incomplete cost information, resulting in poor schedule performance from the overall cost minimizing objective. For such a purpose, we need two types of CPAs : intra-job CPA and inter-job CPA. Whenever there is a change in cost information of an activity in a job in the process of scheduling, the intra-job CPA updates cost curves of other activities connected through temporal constraints within the same job. The inter-job CPA extends cost propagation into other jobs connected through precedence relationships. By utilizing the cost information provided by CPAs, we propose cost-based scheduling heuristics that attempt to minimize the total schedule cost. This paper develops inter-job CPAs that create and update cost curves of each activity in each search state, and propagate cost information throughout a whole network of temporal constraints. Also we propose various cost-based scheduling heuristics that attempt to minimize the total schedule cost by utilizing the cost propagation algorithm.