• Journal of Korean Society for Geospatial Information Science
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• v.20 no.4
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• pp.55-65
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• 2012

The purpose of this study is to construct the System Dynamics Model that can analyze urban spatial and temporal change and suggest the policy directions applicable to U-City Planning in Busan based on the SD model. It reviews previous literatures to elicit U-City issues and performs the case study to simulate urban spatial and temporal changes in Busan. The elicited results are connected into the policy directions of U-City planning. It emphasizes the necessity of business model suggestion based on U-City technology and industry not a tool, the U-City model construction that linkages and integrates the existing cities and new cities, and the excavation of U-City service model reflecting social and demographic changes.

• 한국생태학회:학술대회논문집
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• 1999.05a
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• pp.77.2-77.2
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• 1999

• 한국생태학회:학술대회논문집
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• 1999.05a
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• pp.76.1-76.1
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• 1999

• Proceedings of the Zoological Society Korea Conference
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• 1999.10b
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• pp.144.1-144
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• 1999

No Abstract, See Full Text

• Journal of the Korean Operations Research and Management Science Society
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• v.34 no.1
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• pp.61-83
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• 2009

This study developed a variable demand traffic assignment model by stable dynamics. Stable dynamics, suggested by Nesterov and do Palma[19], is a new model which describes and provides a stable state of congestion in urban transportation networks. In comparison with the user equilibrium model, which is based on the arc travel time function in analyzing transportation networks, stable dynamics requires few parameters and is coincident with intuitions and observations on congestion. It is therefore expected to be a useful analysis tool for transportation planners. In this study, we generalize the stable dynamics into the model with variable demands. We suggest a three stage optimization model. In the first stage, we introduce critical travel times and dummy links and determine variable demands and link flows by applying an optimization problem to an extended network with the dummy links. Then we determine link travel times and path flows in the following stages. We present a numerical example of the application of the model to a given network.

• Journal of the Korean Operations Research and Management Science Society
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• v.32 no.3
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• pp.63-80
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• 2007

This study is a generalization of 'stable dynamics' recently suggested by Nesterov and de Palma[29]. Stable dynamics is a new model which describes and provides a stable state of congestion in urban transportation networks. In comparison with user equilibrium model that is common in analyzing transportation networks, stable dynamics requires few parameters and is coincident with intuitions and observations on the congestion. Therefore it is expected to be an useful analysis tool for transportation planners. An equilibrium in stable dynamics needs only maximum flow in each arc and Wardrop[33] Principle. In this study, we generalize the stable dynamics into the model with multiple traffic classes. We classify the traffic into the types of vehicle such as cars, buses and trucks. Driving behaviors classified by age, sex and income-level can also be classes. We develop an equilibrium with multiple traffic classes. We can find the equilibrium by solving the well-known network problem, multicommodity minimum cost network flow problem.

• Journal of the Korean Institute of Landscape Architecture
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• v.23 no.4
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• pp.12-19
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• 1996

Urban parks, as remnant patches, of two older cities and two new towns can be analyzed by a landscape ecological approach. The index of patch shape, the dispersion of patches, the mean edge length, and the mean patch size of parks of each city are ocmpared. The findings of this study are as follows : 1) The mean edge length of urban parks of older cities is longer than that of new towns : Seoul>Suwon>Bundang>Ansan. 2) The mean patch size of urban parks in Seoul is much greater than those of other cities : Seoul> Ansan>Suwon>Bundang. 3) The index of patch shape of urban parks of older cities is greater than that of new towns : Seoul>Suwon>BundangAnsan. 4) The dispersion of patches is in the order of Bundang >Ansan>Seoul>Suwon. The new towns have relatively even distributions of urban parks than older cities. Further research is required to find out the relationship between the index of patch shape and patch interior dynamics.

• Korean System Dynamics Review
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• v.2 no.2
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• pp.97-118
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• 2001

To solve the policy problem between transportation and environment in trade-offs, above all, it is necessary to understand the complicated relationship between transportation and environment clearly before selecting policy alternatives. From this point of view, this study will propose the logic structure to examine the complex interaction of transportation and environment and investigate theoretically what kinds of impact would appear by the air related polices. In this research, we used ’system-dynamics’ which investigates the complexity through the flow of information and materials and the interaction of elements, which constitutes systems. System Dynamics is an approach that the variables to decide structural relationship in a system affect one another not in only-way but in inter-way and the power of influence changes time by time. This research is trying to examine the complex interaction of transportation and air pollution. For achieving this purpose, causal maps in System Dynamics approach were used. The main issues are as follows; first, to investigate the dynamic relationship between transportation and air pollution caused by exhaust emission gas. Second, to structuralize the logic of simulation to experiment the impacts of policies to relieve air pollution.

• 한국신재생에너지학회:학술대회논문집
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• 2010.06a
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• pp.181.3-181.3
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• 2010

최근들어 전산유체역학(CFD: Computational Fluid Dynamics)은 빌딩에 대하여 다양한 응용분야에서 사용된다. 이번 연구에서는 측정이 어려운 도심지 건물 군을 지나는 바람에 대하여 CFD해석 방법을 이용하여 고층 빌딩 상공을 지나가는 바람장을 예측 하였으며, 예측 된 결과를 실제 측정치와 비교 검증하였다. 바람장 측정 방법은 마스트를 세워서 측정하는 방법, 풍동 실험실에서 축소된 모형에 대한 실험방법, PIV 측정방법, LIDAR, SODAR측정 방법 등 많은 방법이 있다. 이번 연구에서는 가장 정확한 측정 방법인 LIDAR를 사용하여 측정을 수행하였다. 바람장이 측정된 장소는 서울 잠실 롯데 호텔 상공이며, 불어오는 바람은 롯데 월드를 중심으로 주변의 상가 건물들과 아파트 건물들 때문에 불안정하며 고르지 않을 것으로 예상되었다. LIDAR 측정은 일정 기간 동안 이루어 졌다. CFD해석은 임의의 시간대에 대해서 주 풍향에 대해서 해석이 수행되었다. CFD 해석결과는 최종적으로 측정 데이터와 비교 검증이 이루어 졌으며, 두 데이터간의 일치도가 높음을 알 수 있었다.

• Journal of the Economic Geographical Society of Korea
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• v.5 no.2
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• pp.229-248
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• 2002

In the recent years the office sector or industry are recognized not only as a key economic activity and employment source in urban areas, but also as a factor for the changing urban spatial structure. This paper aims to review the research trends and future prospects on the office locations. The study starts with a survey of literatures by summarizing the most important previous studies on the office location research and by disclosing research deficits. And then general locational trends of office activities on the base on the different geographical scale and its current location dynamics including the influencing factors are discussed. Finally this study summarizes the outlooks on the future task within office location research.