• Korean System Dynamics Review
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• v.16 no.1
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• pp.75-91
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• 2015

The price-volume in land by land categories is evaluated with dynamic approaches in the era of aging society This research tries to investigate in the respect of major factors such as real estate, macro-economics, and population that is simulated by land categories. The system dynamics approaches on price-volume in land are forecasted until 2020 using the data in the period of 2000-2014. In regard to methodologies, this research adopted system dynamics to evaluate the relationships between price-volume in land and aging society. The meaningful results have been found during the last over 10 year's analysis as the dynamic relations with major factors. Regarding land categories, this research tries to overcome former research limitations. As an implication from the price-volume in land, it confirmed that the multifaceted aspects show that system dynamics approach effectively simulated them by price-volume in land with the population of aging society.

• Korean System Dynamics Review
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• v.12 no.1
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• pp.75-87
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• 2011

Congestion problems can be approached from the viewpoint of system dynamics theory. The relationship between road capacity and congestion can be explained by the 'relative control' archetype among four system archetypes suggested by Wolstenholme. There is a balancing feedback loop between road capacity and road congestion. However, there is another balancing loop between road congestion and car traffic volume, which keeps disrupting the equilibrium of the former loop. A system dynamics model, which is based on a partial adjustment model of induced traffic in the literature, is built to simulate three road building scenarios: 'Expanding investment', 'Balancing investment' and 'Frozen road investment' scenarios. The 'Expanding investment' scenario manages to drop congestion levels by 9% over 30 years, however, causing much higher emissions of $CO_2$ than other scenarios. The trade-off relationship between congestion levels and environmental costs must be taken into consideration for road investment policies.

• 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.

• Transactions of the Korean Society of Automotive Engineers
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• v.10 no.3
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• pp.185-191
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• 2002

A window-based multibody dynamics program CADyna(Computer Aided Dynamics) is developed and applied for kinematic and dynamic analysis ova steering system. The program is composed oft pre-processor, a main processor, and a post-processor. The pre-processor is developed with Visual C7+ and the post-processor is developed with OpenGL and TeeChart. The main processor generates the equations of motion employing velocity transformation technique. The developed program is customized for the design of an intermediate shaft in a steering system.

• Korean System Dynamics Review
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• v.11 no.2
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• pp.119-138
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• 2010

This study introduces the system dynamics model that simulate total operational availability when 10 equipments made of 3 major components are serviced under the constrains of the maintenance capacity level and the number of spare parts. This simulation is designed on the base of reliability engineering concept so failures of components happens with the rule of engineering factors like the mean time between failure(MTBF) of component and the next failure time of one component is effected by the conditions of other components. We analysed availability of 10 equipments under 121 constrains and executed multiple regression analysis with the simulation result. The analysis provide the managerial insight in the service fields with operation many equipments.

• Korean System Dynamics Review
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• v.1 no.1
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• pp.29-56
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• 2000

During the past few years, cyberspace and electronic commerce has been expanding throughout the world rapidly. The purpose of this paper is to find out policy leverages for boosting up cyberspace and electronic commerce using system dynamics simulation modeling approach. The system dynamics simulation model developed in this paper allows analysis of both the effect of factors on dynamic growth pattern of cyberspace as well as the effect of time delay in information processing, money transfer and delivery on model behavior. Finding of this study is that capacity of information infrastructure and size of cyberspace population are key factors of cyberspace growth. Also, reducing time delay in information flow, money flow, and delivery flow is an important policy leverages for growth of electronic commerce.

• Journal of Astronomy and Space Sciences
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• v.26 no.2
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• pp.267-278
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• 2009

Automation of the key flight dynamics operations for the geostationary orbit satellite mission is analyzed and designed. The automation includes satellite orbit determination, orbit prediction, event prediction, and fuel accounting. An object-oriented analysis and design methodology is used for design of the automation system. Automation scenarios are investigated first and then the scenarios are allocated to use cases. Sequences of the use cases are diagramed. Then software components and graphical user interfaces are designed for automation. The automation will be applied to the Communication, Ocean, and Meteorology Satellite (COMS) flight dynamics system for daily routine operations.

• Korean System Dynamics Review
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• v.12 no.3
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• pp.5-23
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• 2011

Studies in social science are performed on the language of social actors. While a metaphor analysis focuses on the meaning of the language, a cognitive map analysis deals with its external relationships. If we can put together both analyses, it will be possible to investigate the internal meanings and external relationship of the language and image at the same time. In this paper, metaphor analysis and cognitive map approach is applied to find the image of local governments. This study shows how to link metaphor analysis to the cognitive map and the benefit of using both approaches together.

• Transactions of the Korean Society of Automotive Engineers
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• v.12 no.6
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• pp.175-181
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• 2004

This paper presents the main method to analyze the dynamic characteristics of power transmission system using the multi-body dynamics, which is based on the concept of subsystem equation, subsystem assembling, and the self-determination technique for the system degree of freedom. We can model the mechanical components of power transmission system easily with the advantage of multi-body dynamics. Based on the theory, a dynamic simulation program was developed to analyze system performances, transient phenomena, and other dynamic problems. The driving performance of automatic transmission was simulated with using the multi-body dynamics and Newtonian method, and the validity of program was proved by comparing the two kinds of result.

• Korean System Dynamics Review
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• v.6 no.1
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• pp.177-192
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• 2005

A system dynamics model is developed to investigate policies for the school-age child weights and heights. The model is based upon the system dynamic model of Soonhee lee(2003), the purpose of which was policy analysis for obese control of adult people. Although the purpose and target people are different, the main structure can be applied to in the same way. Besides the carbohydrate, protein, and fat material, the new model covers hormone and heights with new input mechanisms for foods and activities. The simulation results matches well with the average school-age children in Korea with the average inputs data (foods and activities). The model can be used for various purposes such as policy analyses, care plan for obese children, etc.