• Journal of the Korea Society for Simulation
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• v.8 no.3
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• pp.67-76
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• 1999

The study of the optimization of operating policy of AGV system, which is used in many factory automation environments has been proceeded by many researchers. The major operating policy of AGV system consists of routing and scheduling policy. AGV routing is composed with collision avoidance and minimal cost path find algorithm. To allocate jobs to the AGV system, AGV scheduling has to include AGV selection rules, parking rules, and recharging rules. Also in these rules, the key time parameters such as processing time of the device, loading/unloading time and charging time should be considered. In this research, we compare and analyze several operating policies of multiple loop-multiple AGV system by making a computer model and simulating it to present an appropriate operating policy.

• Management & Information Systems Review
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• v.4
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• pp.309-325
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• 2000

Organizations rely on Secure ID resources today to handle vast amounts of information. Because the data can vary widely in type and in degree of sensitivity, employees need to be able to exercise flexibility in handling and protecting it. It would not be practical or cost-effective to require that all data be handled in the same manner or be subject to the same protection requirements. Without some degree of standardization, however inconsistencies can develop at introduce risks. Policy formulation is an important step toward standardization of security activities for ID resources. ID security policy is generally formulated from the input of many members of an organization, including security officials, line managers, and ID resource specialists. However, policy is ultimately approved and issued by the organization's senior management. In environments where employees feel inundated with policies, directives, guidelines and procedures, an ID security policy should be introduced in a manner that ensures that management's unqualified support is clear. The organization's policy is management's vehicle for emphasizing the commitment to ID security and making clear the expectations for employee involvement and accountability. This paper will discuss ID security Policy in terms of the different types (program-level and issue-specific), components, and Implementation of Expert System Simulation based on 4GL, PowerBuilder.

• Journal of the Korea Society for Simulation
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• v.17 no.4
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• pp.209-218
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• 2008

The Unified Modeling Language becomes popular to specify, visualize, construct, and document software-intensive systems, especially in supporting the design phase of software engineering. Most of designs in UML have focused on firm designing of software system structure. Recently, some researches have raised additional demands in many emerging complex software systems, such as aspect-oriented design. In this paper, we work on the dynamic aspect of policy-driven architecture. We present a UML-based high-level modeling of policy-driven management which is applicable in various application domains. In order to manage a number of activities of applications, dynamics and flexibility should be supported with policies consistently on different resources in the same context. Thus, a methodology of meta-modeling to represent dynamic aspects of policy-driven architecture is studied. Based on our methodology, we could achieve meta-modeling to develop a number of policy-driven management applications.

• Journal of Digital Convergence
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• v.12 no.8
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• pp.377-387
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• 2014

The purpose of this study is to suggest improvement ways of outpatient process via a simulation model and to improve operational efficiency. Three experimentation scenarios were implemented into the simulation model to determine which proposed scenario provides better improvement in terms of the following performance measures: LOS(Length of Stay), patient waiting time, patient travel time, and staff utilization. The hospital medical data collection and statistical tools used to analyze the process mining tools. And the PIOS simulation tool was used and the validity of the model was verified by using t-test. The simulation results demonstrated that oupatient process of center type is most efficient. Simulation approach is a powerful technique that supports efficient decision-making compared to traditional healthcare management approach based on past experience, feelings, and intuition. Therefore, the proposed experimentation model has wide applicability in healthcare systems.

• IE interfaces
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• v.14 no.1
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• pp.30-38
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• 2001

Logistics network management has become one of the most important sources of competitive advantage regarding logistics cost and customer service in numerous business segments. Logistics network simulation is a powerful analysis method for designing and planning the logistics network optimally in an integrated way. This paper introduces a logistics network simulator, LONSIM, developed by author. LONSIM deploys a mix of simulation and optimization functions to model and analysis logistics network issues such as facility location, inventory policy, manufacturing policy, transportation mode, warehouse assignment, supplier assignment, order processing priority rule, and vehicle routes. LONSIM is built with AweSim 2.1 and Visual Basic 6.0, and executed in windows environment.

• 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.

• The Journal of Korean Academic Society of Nursing Education
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• v.15 no.2
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• pp.183-193
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• 2009

Purpose: The purpose of this study was to explore experiences among undergraduate nursing students in a high-fidelity simulation education course for a semester. Method: The participants in this study were 10 nursing students in the senior classes and volunteers. Data collection was conducted using a focus group interview for 100 minutes, which was recorded on video tape. Transcribed data was analyzed through qualitative content analysis. Result: The results of this study were deduced as 4 codes and 22 themes. Study participants reported experiences due to the simulation method itself, interaction among peer group and personal experiences during high-fidelity simulation education. Additionally, experiences related to clinical application were examined. The participants indicated positive outcomes such as developing clinical judgment skills and confidence. Conclusion: Overall, the results of this study supported the usability and effectiveness of a high-fidelity simulation education method in undergraduate nursing curriculum. Further studies are needed to provide more reliable and valid educational information.

• KDI Journal of Economic Policy
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• v.43 no.4
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• pp.45-67
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• 2021

We analyze the social welfare effect when a policy-based financial system (PFS) enters a decentralized financial market. Particularly, the PFS in this case supports the interest spread for corporate loans held by firms with heterogeneous bankruptcy decisions under an imperfect information structure. Although support for capital costs through the PFS expands the economy consistently, the optimal level of PFS out of the corporate loan market is estimated to be 8.6% by a simulation model considering social welfare adjusted by the disutility of labor. This result is much lower than the recent level of PFS in the Korean financial sector.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2015.05a
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• pp.649-652
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• 2015

Previous marking policy for the AF service of TCP traffic in the Diffserv network have no sufficient consideration on the effect of RTT and target rate. In this paper, in order to improve fairness Index by the effect RTT difference of TCP traffic, we propose the modified TSW3CDM(Time Sliding Window Three Color Dynamic Marker) based on average transfer rate estimation and the flow state. The proposed algorithm is dynamic marking policy that do allocate band width in proportion to transmission rate. To evaluate the performance of the proposed algorithm, We accomplished a computer simulation using NS-2. From simulation results, the proposed TSW3CDM algorithm improves fairness index by comparison with TSW3CM.

• Journal of the Korea Society for Simulation
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• v.27 no.4
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• pp.1-8
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• 2018

The most common way to control a target point using artificial intelligence is through reinforcement learning. However, it had to process complicated calculations that were difficult to implement in order to process reinforcement learning. In this paper, the enhanced Proximal Policy Optimization (PPO) algorithm was used to simulate finding the planned flight trajectory to reach the target point in the virtual environment. In this paper, we simulated how this problem was used to find the planned flight trajectory to reach the target point in the virtual environment using the enhanced Proximal Policy Optimization(PPO) algorithm. In addition, variables such as changes in trajectory, effects of rewards, and external winds are added to determine the zero conditions of external environmental factors on flight trajectory learning, and the effects on trajectory learning performance and learning speed are compared. From this result, the simulation results have shown that the agent can find the optimal trajectory in spite of changes in the various external environments, which will be applicable to the actual vehicle.