• Journal of Navigation and Port Research
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• v.40 no.5
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• pp.345-351
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• 2016

This study presents a system dynamics methodology to evaluate quantitatively the effect of the Korean government's development policy, such as tax reductions, on the industrial economy. System dynamics is often perceived as an optimized means to identify the dynamic inter-relationships among various factors of development policies, and in particular the industrial characteristics and uncertainties of the coastal shipping industry. The results of simulations used in this study shows that the impact of development policies such as tax reductions would increase shipping demand for about 4 years, and that tax incentives could raise the demand volume for cabotage cargo from 5.26 to 11.11%, through the available freight-down by 90~95% points. The system dynamics approach used in this paper represents an initial attempt to use this methodology in studies of the coastal shipping industry. On the basis of our simulations, the industrial effects of other development policies, such as ship financing support, investment of social overhead, or crew supply, could also be analyzed effectively. Additionally, it should be possible to extend these results by developing a comprehensive model encompassing these various analyses.

• Korean System Dynamics Review
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• v.8 no.1
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• pp.187-209
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• 2007

This paper deals with the policy failure in housing markets. In order to understand basic mechanism leading to policy failure, systems thinking and system dynamics modeling is applied to housing markets and housing policy. This paper will show different set of causal maps on housing policy, and compare causal reasons of housing policy and its critics.

• Korean System Dynamics Review
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• v.12 no.1
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• pp.39-57
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• 2011

This paper is the result of simulation modeling concerning high-level radioactive waste repository(HLRWR) and people's mind for the facility. We describe a procedure of simulation modeling for resident's policy acceptance and perceived risk of HLRWR facility by using System Dynamics approach. To Complete some complicated works, we made the 20 pieces of stock-flow diagrams based on the causal loop diagram that is a blue print of whole variables and relations. The simulation outputs clearly show that cental government efforts to siting the HLRWR will be failed if nothing to give for the region's residents. On the contrary, a monetary incentive and a regional development program help to turn this gloomy situation into a desirable and acceptable condition dramatically. Government has to prepare the schemes considering the HLRWR acceptance and total supporting program including the cash and local development programs.

• Korean System Dynamics Review
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• v.10 no.3
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• pp.25-45
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• 2009

The concept of social capital has recently been highlighted in most fields of social science because social capital is believed to be an alternative of market and government failures. However, social capital is of high ambiguity that hinders in conceptualizing and modeling that can differs from the premises, such as whether social capital lies in individual actors or collective substances, or whether social networks are functioning by rationality or emotion. This study therefore tries to examine the concept of social capital and suggest 6 types of it following by the anthropologic concept of 'reciprocity' as well as to provide fruitful discussions on the introduction of social capital variables to System Dynamics modeling of sustainable development. Conclusively, the introduction of social capital to the integration models of environment-economy-society should be based on strongly understanding the social networks, individual identities, and local particularities of the relevant localities in order to enhance the structural validity and applicability of sustainable development models in System Dynamics.

• Korean System Dynamics Review
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• v.13 no.3
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• pp.23-46
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• 2012

The purpose of this paper is to estimate effects of healthy city policies on reducing social costs. The analyses were dune at the cities, counties, and communities levels in 2009, and covered Seoul Metropolitan Area(SMA). For estimation of reducing social costs, it developed a system dynamics(SD) model that analyzed causal relationships between physical inactivity rates, the number of deaths, medical expenses, and total social costs. Simulation period of SD was from 2009 to 2030. Three alternatives were proposed with combinations of length of bike lanes, number of bus routes, crime rates, self-reported good health status rates, and obesity rates. The total estimated cost of physical inactivities from 2009 to 2030 was 31.9 trillion won from the future forecast without policies. As a result of simulations with three alternatives, there were economic benefit approximately from 119.7 billion won to 1.16 trillion won. This study contributed to better understanding the economic benefits of healthy cities that were associated with design of built environment and physical activity. It also emphasized the importance of healthy cities planning as one of national welfare polices.

• Journal of the Korean Operations Research and Management Science Society
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• v.8 no.2
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• pp.9-25
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• 1983

A new approach to cross impact analysis using probabilistic system dynamics(PSD) is presented in this article. The previous models using PSD consist of system dynamics models as a basis which are interacting with cross impact analysis (CIA) sectors. In this model, the policy impact analysis part is separated from the CIA sectors and is constituted an independent subsectors of the model. The policy subsector is designed to separate the policy impact and provide feedback both to the system dynamics base model and cross impact analysis sectors. The new technique is applied to the forecasting, assessment and policy formulation of air pollution in Seoul metropolitan area in 2,000. The results show that the new tool consider policy effects more effectively than the previous PSD models.

• 제어로봇시스템학회:학술대회논문집
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• 1989.10a
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• pp.669-674
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• 1989

Robot manipulators are highly coupled nonlinear systems and their motions are influenced by uncertain dynamics. In this paper a design methodology which is called model feedback control system or plant model control scheme is presented for the purpose of reducing the influence of the uncertain dynamics. This control system is applied to the trajectly control of the directly drived robot. Theoretically and experimentally performances resulting from use of this control scheme show that the influences of the uncertain dynamics are reduced obviously.

• Proceedings of the Korean System Dynamics Society
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• 2007.06a
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• pp.113-129
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• 2007

Due to criminal aspects spreading nation wide, their intelligence level increasing and becoming digitalized, the citizens' interest in and desire for crime security have increased. Until now, the preceding researches have been focused on finding the specific variables that have direct effects on the demand for police manpower through regression analysis and attempted to predict number of needs. However, there have never been any researches producing the accurate number of demands for crimes and human resources needed for each work load. Therefore, this research have analyzed each police station functions by interviewing the persons in charge and selected the main duty for each functions. From this, by using the method of system dynamics, this research was able to predict the standard number of manpower needed for each police station functions. Also, by making a model for each 235 police stations, the best efficient employment plan for police stations and district agencies have been further discussed based on the computer simulation results.

• 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.

• International Journal of Aeronautical and Space Sciences
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• v.18 no.2
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• pp.245-254
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• 2017

In this paper, deployment dynamics of large-scale flexible solar arrays with deployable mast is investigated. The adopted solar array system is introduced firstly, then kinematic description and kinematic constraint equations are deduced, and finally, dynamics equation of the system is established by the Jourdain velocity variation principle and a new method to deal with topology changes of the deployable mast is introduced. The dynamic behavior of the system is studied in detail. Simulation results indicate that the proposed model is effective to describe the deployment dynamics of the solar arrays and that the introduced method is applicable for topology changes.