• The Transactions of the Korean Institute of Electrical Engineers D
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• v.50 no.3
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• pp.120-129
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• 2001

A two-degree-of-freedom quarter-car model is used as the basis for LQ and the proposed controller design for a semi-active suspension. The LQ controller results in the best rms performance trade-offs(as defined by performance index) between ride, handling and packaging requirements. In LQ controller, however, the conflict between road holding and ride comfort remains. The adaptive semi-active suspension control based on the road frequency are introduced in this paper. With this method, the trade-off between road holding and ride comfort can be relaxed. The road frequency is estimated by wavelet transform if rattle space signal. The simulation results show that the proposed controller is superior to the conventional LQ controller.

• Journal of the Korea Society for Simulation
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• v.17 no.2
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• pp.91-103
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• 2008

In order to simulate the behavior of automated manufacturing systems, the performance of material handling systems should be measured dynamically. Multi-Agent technology could be well adapted for the development of simulator for distributed and intelligent manufacture systems. A multi-agent system is composed of one coordination agent and multiple application agents. Issues in AGVS simulator can be classified by the set-up and operating problems. Decisions on the number of vehicles, bi- or uni-directional guide-path, etc. are fallen into the set-up problem category, while deadlock tree algorithm and conflict resolution are in operating problem. In this paper, a multi-agent based deadlock-free simulator for automated guided vehicle system(AGVS) are proposed through the use of multi-agent technologies and the development of deadlock-free algorithm. In this AGVS simulator proposed, well-known Floyd algorithm is used to create AGVS Guide path, through which AGVS move. Also, AGVs avoid vehicle conflict and deadlock using check path algorithm. And Moving vehicle agents are operated in real-time control by coordination agent. AGV position is dynamically calculated based on the concept of rolling time horizon. Simulator receives and presents operating information of vehicle in AGVS Gaunt chart. The performance of the proposed algorithm and developed simulator based on multi-agent are validated through set of experiments.

• Proceedings of the Korea Information Processing Society Conference
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• 2017.04a
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• pp.315-318
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• 2017

Nowadays, Distributed Denial of Service (DDoS) attacks have gained increasing popularity and have been a major factor in a number of massive cyber-attacks. It could easily exhaust the computing and communicating resources of a victim within a short period of time. Therefore, we have to find the method to detect and prevent the DDoS attack. Recently, there have been some researches that provide the methods to resolve above problem, but it still gets some limitations such as low performance of detecting and preventing, scope of method, most of them just use on cloud server instead of network, and the reliability in the network. In this paper, we propose solutions for (1) handling multiple DDoS attacks from multiple IP address and (2) handling the suspicious attacks in the network. For the first solution, we assume that there are multiple attacks from many sources at a times, it should be handled to avoid the conflict when we setup the preventing rule to switches. In the other, there are many attacks traffic with the low volume and same destination address. Although the traffic at each node is not much, the traffic at the destination is much more. So it is hard to detect that suspicious traffic with the sampling based method at each node, our method reroute the traffic to another server and make the analysis to check it deeply.

• Proceedings of the KSME Conference
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• 2007.05b
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• pp.3080-3085
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• 2007

Shape optimization of the 3-dimensional WIG airfoil with 3.0-aspect ratio has been performed by using the multi-objective genetic algorithm. The WIG ship effectively floating above the surface by the ram effect and the virtual additional aspect ratio by a ground is one of next-generation and cost-effective transportations. Unlike the airplane flying out of the ground effect, a WIG ship has possibility to capsize because of unsatisfying the static stability. The WIG ship should satisfy aerodynamic properties as well as a static stability. They tend to strong contradict and it is difficult to satisfy aerodynamic properties and static stability simultaneously. It is inevitable that lift force has to scarify to obtain a static stability. Multi-objective optimization technique that the individual objectives are considered separately instead of weighting can overcome the conflict. Due to handling individual objectives, the optimum cannot be unique but a set of nondominated potential solutions: pareto optimum. There are three objectives; lift coefficient, lift-to-drag ratio and static stability. After a few evolutions, the non-dominated pareto individuals can be obtained. Pareto sets are all the set of possible and excellent solution across the design space. At any selections of the pareto set, these are no better solutions in all design space

• Industrial Engineering and Management Systems
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• v.12 no.4
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• pp.389-405
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• 2013

A facility layout design (FLD) problem can be generally introduced as assignment of facilities (departments) to a site such that a set of criteria are satisfied or some objectives are minimized (maximized). Hence, it can be considered as a multi-criteria problem due to the presence of qualitative criteria such as maintenance or flexibility and quantitative criteria such as the total cost of handling material. The VIKOR method was developed to solve multiple criteria decision making problems with conflicting and non-commensurable (different units) criteria, assuming that compromising is acceptable for conflict resolution, the decision maker wants a solution that is the closest to the ideal, and the alternatives are evaluated according to all established criteria. This paper proposes a hierarchical analytic hierarchy process (AHP) and VIKOR approach to solve the FLD problem. A computer-aided layout-planning tool is adopted to generate the facility layout problems, as well as their quantitative data. The qualitative performance measures are weighted by AHP. VIKOR is then used to solve the FLD problem. Finally, the proposed integrated procedure is applied to three real-time examples.

• Research in Community and Public Health Nursing
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• v.25 no.4
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• pp.270-281
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• 2014

Purpose: The purpose of the study was to understand low-income elders' experiences of community-based u-Health services. Methods: Qualitative data were collected from 11 participants. All interviews were recorded and transcribed verbatim. The transcribed data were analyzed using qualitative content analysis. Results: Three themes and eight sub-themes emerged as a result of analysis. The three main themes were 'recovered confidence and health condition,' 'trial and error in change,' and 'hope.'The eight sub-themes were 'the burden and efforts to overcome it in using bio-signal device,' 'ambivalence due to changing lifestyle,' 'increase of care time, decrease of pressure', 'conflict under environmental constraints,' 'difficulty in prioritizing health management,' 'discouragement in handling new devices,' 'desire not to be a burden to their children-gradual fulfillment of learning needs,' and 'long for broadening coverage range of services.' Conclusion: The findings of this study demonstrate that low-income elders among the participants have different needs in using u-Health services. Therefore, health professionals need to give personalized education to deal with their conflicts and requirements, especially emotional and environmental support in order for them to successfully accept the u-Health services for self-care.

• Journal of Fisheries and Marine Sciences Education
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• v.25 no.5
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• pp.1214-1223
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• 2013

The purpose of this work is to analyze the factors, criteria and importance that shippers in the international logistics industry take into account in choosing third-party logistics, and thereby to propose the directions of the areas and functions that third-party logistics will need to enhance on the basis of Analytic Hierarchy Process (AHP) methodology. To do that, this work collected and analyzed materials about changing environments of logistic industry and previous studies, and especially conducted a questionnaire survey on the factors to choose third-party logistics with the study subjects of shippers in the international logistics industry. To draw attribute factors, this work repeatedly chose and classified candidate factors through Delphi technique on the basis of the data of previous studies. The analysis results are presented as follows: regarding pairwise comparison between logistic cost and logistic service in relation of conflict, logistic service was recognized to be more important than logistic cost; regarding pairwise comparison between corporate capability and logistic cost, logistic cost was recognized to be more important; and regarding comprehensive evaluation, logistic service factors, including accuracy of order handling, service reliability, freight damage and compensation, a degree of fulfillment of promise, quality of transportation, and problem-solving ability, were found to be in high position.

• Journal of Arbitration Studies
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• v.24 no.2
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• pp.81-107
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• 2014

ADR has recently been expanded, making it possible to solve traffic accident disputes, which is a matter of urgency for parties to avoid. This point serves as an important procedural element. Such disputes are an area that requires a quick resolution. To try to solve any dispute that occurs in the complex environment of modern times one-by-one through litigation does not make sense. It gives an undue burden on the judicial body and the investigation agency. Like litigation, today's arbitration system, should have effective conflict resolution. The arbitration of automobile traffic accident disputes can be seen as roughly adjusted through the insurance company, the Dispute Coordinating Committee, and the Crime Victims Protection Act. It consists of experts mainly, and the resolution of automobile traffic accident disputes can be resolved through the Sajonsa and workers insurance company. However, adjustments to failure incident mostly need attention. Most of a company's compensation insurance indemnity needs to be processed in practice. In addition, a vicious cycle of litigation and delay period is repeated if a lawyer is appointed. There are unreasonable adjustment systems in the midst of these. Avoiding traffic accidents allows parties to resolve disputes better. Arbitration of disputes in automobile traffic accidents handled by arbitration institutions is desirable. It is determined that the handling of a case by a village attorney is efficient.

• The Korean Journal of Emergency Medical Services
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• v.23 no.2
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• pp.7-18
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• 2019

Purpose: This study aimed to determine the core competencies for 119 emergency medical technicians (EMTs) and to provide evidence for the development and utilization of 119 EMTs, education and training programs. Methods: Data were collected with a questionnaire that consisted of items on the general characteristics of the subjects (8 items) and importance and satisfaction levels for 10 competencies, including 34 items on subfactors. The Borich Needs Assessment Model was used in designing the questionnaire. A locus for focus model was used to derive the top priority competencies for the improvement of core competency in the profession. Data were analyzed with by SPSS ver.21 (IBM, Armonk, NY, USA). Results: The core competencies for 119 EMTs were derived from technical competency, information competency, communication competency, problem-solving competency, self-development competency and interpersonal competency. In addition, among the sub-factors of these competencies, 16 abilities (including leadership), ability to apply technical knowledge, technical comprehension, conflict management ability, ability to create documents, problem handling ability, ability to think, technical selection ability, and computer literacy were included in the priority category. Conclusion: This study derived and presented the core competencies for 119 EMTs to enable them to meet the modern day requirements of their roles, which may contribute to enhancing their professionalism.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 2003.09a
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• pp.28-31
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• 2003

In the present work, a main purpose is to propose a fuzzy integral-based aggregation framework to complementarily combine partial information due to lack of completeness. Based on Choquet integral (CI) viewed as monotone expectation, we take into account complementary, non-interactive, and substitutive aggregations of different sources of defective information. A CI-based system representing upper, conventional, and lower expectations is designed far handling three aggregation attitudes towards uncertain information. In particular, based on Choquet integrals for belief measure, probability measure, and plausibility measure, CI$\_$bi/-, CI$\_$pr/ and CI$\_$pl/-aggregator are constructed, respectively. To illustrate a validity of proposed aggregation framework, multiple matching systems are developed by combining three simple individual template-matching systems and tested under various image variations. Finally, compared to individual matchers as well as other traditional multiple matchers in terms of an accuracy rate, it is shown that a proposed CI-aggregator system, {CI$\_$bl/-aggregator, CI$\_$pl/-aggregator, Cl$\_$pl/-aggregator}, is likely to offer a potential framework for either enhancing completeness or for resolving conflict or for reducing uncertainty of partial information.