• Korean System Dynamics Review
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• v.12 no.2
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• pp.95-126
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• 2011

This paper aims at developing a System Dynamics model with an augmented predator-prey interaction structure to deal with the population management of roe deer in Jeju, Korea. Although people still regard the creature as one of the important tourist attractions, there has been much debate on the issues of the appropriateness of the population size of roe deers because they have been stigmatized as crop damagers, and roadkill/poaching victims due to their natural habit to move around from the top mountain to the lowland of the island. The model is therefore to incorporate these migrating and grazing behaviors into an augmented Lotka-Volterra model coupling roe deer population in both parts of the island to that of predators and preys of the species. The authors also provide a comprehensive set of dynamic hypotheses and relevant CLD/SFD to understand the population dynamics of roe deer and co-evolving species and perform the steady-state analysis of the proposed equation system to verify the model behavior of the numerical example lastly presented in this paper.

• Korean System Dynamics Review
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• v.4 no.2
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• pp.71-94
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• 2003

The purpose of this dissertation is to build a development density control model and estimate optimum developmental density level for a sustainable urban growth management. To develop the model, system dynamics modeling approach was used. The model was developed to analyze how urban growth, transition, and decay occur depending on the interaction among population, houses, industry structure, land and urban infrastructure such as road, water supply, and sewage treatment facilities. The model was applied to Anyang city to estimate optimum density level. Extensive computer simulation was conducted to find out the maximum numbers of population, industry structure, houses, and cars that can be adequately sustained with the current Anyang city's infrastructure capacity. The computer simulation result shows that the city is overpopulated by some 90,000 people. It nab analyzed that 20％ increase of existing capacity of urban infrastructure is necessary to support current population of Anyang city. To reduce the population to the adequate level whereby the current urban infrastructure can sustain, the current city regulation on floor area ratio needs be strengthened at least 20％ to 35%.

• Korean System Dynamics Review
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• v.7 no.2
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• pp.97-120
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• 2006

This paper deals with the extension of and discussion on the System Dynamics model (Jeong & Jeon, 2005) of river crabs in Korea. The previous model has been elaborated to empirically search for the optimal restoration and harvest rates of crabs in the Imjin River, on the basis of theoretical models of population dynamics in the field of bio-mathematics and environmental economics. In this paper, the authors tries to couple a series of new feedback loops related to density restrictions and cannibalistic behaviors with a stage-structured model of the crab ecosystem, and also to endogenize the parameter of baby crabs' survival that is caused by water quality improvement and income increase. Through these extensions and relaxations, the authors are able to argue about the strategic decision of the optimal rates additional considerations as well as the properties of the integrated system that was not covered in the previous paper.

• Korean System Dynamics Review
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• v.3 no.1
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• pp.131-163
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• 2002

This study examines the effect that the prepaid trust has in saving the troubled business. Developing a formal system dynamics model, building on case studies of corporate turnaround, we developed a mathematical model on the relationship between the prepaid trust and corporate turnaround. The Model shows how the prepaid trust can shift an organizational system from fragile condition to resilient condition of a firm. This study elaborartes a new set of conditions under which organizations may turn around via prepaid trust of stakeholders.

• Korean System Dynamics Review
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• v.6 no.1
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• pp.17-32
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• 2005

An agricultural commodity production cycle model consisting of corn, beef, and dairy sectors was constructed for the purpose of exploring the propagating effects of large-scale disruptive events. In an initial proof-of-concept exercise, we considered an agricultural disruption scenario in which foot-and-mouth disease (FMD) is introduced into the U.S., causing a large-scale outbreak of the disease in both beef and dairy cattle. The magnitude of disruption to the beef and dairy sectors are presented under the existing W response policy and then improvements under two alternative policies are shown.

• Korean System Dynamics Review
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• v.6 no.2
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• pp.95-116
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• 2005

The purpose of this study is to analyze the structure of renewable energy market in order to deploy more renewable energy in Korea on the basis of information asymmetry between suppliers and demanders. To attain this purpose we develop the model to analyze and simulate the renewable market using system dynamics. This model is developed not to forecast the accurate size of market but to learn more structure of market using our limited data, mental model and knowledge of market.

• Journal of the Korean Mathematical Society
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• v.57 no.4
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• pp.987-1004
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• 2020

Motivated by the traffic flow model with Arrhenius looka-head relaxation dynamics introduced in [25], this paper proposes a traffic flow model with look ahead relaxation-behind intensification by inserting look behind intensification dynamics to the flux. Finite time shock formation conditions in the proposed model with various types of interaction potentials are identified. Several numerical experiments are performed in order to demonstrate the performance of the modified model. It is observed that, comparing to other well-known macroscopic traffic flow models, the model equipped with look ahead relaxation-behind intensification has both enhanced dispersive and smoothing effects.

• Management Science and Financial Engineering
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• v.19 no.1
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• pp.37-41
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• 2013

This study presents an application of stochastic model for limit order book (LOB) dynamics to Korean Stock Index Futures (KOSPI 200 Futures). Since KOSPI 200 futures market is widely known as one of the most liquid markets in the world, direct application of an existing model is hardly possible. Therefore, we modified an existing model to successfully model and predict the dynamics of extremely liquid KOSPI 200 futures market.

• Korean System Dynamics Review
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• v.7 no.2
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• pp.171-189
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• 2006

This article aims to develop a model for analysing the relationships among the factors affecting the national competitiveness and to explore the future trend of Korea's national competitiveness using a system dynamics approach. For this purpose the article examines the national competitiveness indexes being published by the international institutions such as IMD and WEF. The article also demonstrates how national competitiveness may be strengthened and finally suggests that the national competitiveness should be studied systematically in the future.

• Proceedings of the Korean System Dynamics Society
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• 2004.02a
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• pp.109-128
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• 2004

A system dynamics model is developed in order to evaluate the contribution level of the activities regarding HANARO, which is the research reactor in Korea. The system dynamics model has room to be improved, but it is logically sound enough to evaluate the general level of contributions and to develop strategies for the HANARO to be more contributable. Considering the uncertainty involved with the input variables, the contribution level is ranged from 3 times to about 30 times of the investment made on it. The evaluation results can be summarized as follows : (Table Omitted).