• 한국시스템다이내믹스연구
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• 제2권2호
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• pp.97-118
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• 2001

To solve the policy problem between transportation and environment in trade-offs, above all, it is necessary to understand the complicated relationship between transportation and environment clearly before selecting policy alternatives. From this point of view, this study will propose the logic structure to examine the complex interaction of transportation and environment and investigate theoretically what kinds of impact would appear by the air related polices. In this research, we used ’system-dynamics’ which investigates the complexity through the flow of information and materials and the interaction of elements, which constitutes systems. System Dynamics is an approach that the variables to decide structural relationship in a system affect one another not in only-way but in inter-way and the power of influence changes time by time. This research is trying to examine the complex interaction of transportation and air pollution. For achieving this purpose, causal maps in System Dynamics approach were used. The main issues are as follows; first, to investigate the dynamic relationship between transportation and air pollution caused by exhaust emission gas. Second, to structuralize the logic of simulation to experiment the impacts of policies to relieve air pollution.

• 한국시스템다이내믹스연구
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• 제12권4호
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• pp.63-92
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• 2011

The purpose of this paper is to investigate a possibility of applying multimethodological approach for solving a dilemma. The motivation of this attempt is that the two different approaches, the system dynamics and the theory of constraints, resemble each other in having mental models for describing the target system and using graphic tools for representing those mental models. After a brief discussion on the comparison of the two approaches, a combined method applying to the problem of dilemma is suggested. For an experimental example, the proposed approach is applied to the sales and finance conflict on an inventory issue. The study shows that the suggested approach is able to complement each other's drawbacks. Especially constructing a stock-and-flow model and implementing a computer simulation would be very useful for quantifying the system's behavior which is hardly tracked down when applying the theory of constraints alone.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1988년도 전기.전자공학 학술대회 논문집
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• pp.841-842
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• 1988

For determination of black-out area and restoration area by an expert system for fault section estimation and power system restoration using information from circuit breakers, it is necessary that the recognition of system isolation state and a method of finding the change of system isolation state by the state transition of breakers in isolated system. This paper presents a method of resolving the above problem by rule-based approach.

• 한국군사과학기술학회지
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• 제7권1호
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• pp.13-23
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• 2004

There are several kinds of error factors in control system design. All error factors must be analysed before designing the control system. Therefore, each error factor must be compensated and eliminated completely. Systems Engineering can solve these error factors. In this paper, systems engineering approach on control system design are studied under model based systems engineering with RDD-100, Matlab-Simulink. Systems Engineering shall be used in defense development from control system design to system development.

• 한국항만학회지
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• 제12권2호
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• pp.243-250
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• 1998

This study is to find subjects for the Automated Container Terminal(ACT) development and container terminal system. Also we analyze the present condition of the container terminal system in Pusan port and its automation level by systems approach. And this paper aims at evaluating on the priority of R&D investment until the beginning of the second stage of New Pusan Port Project(2006). In this process we have considered 8 evaluation indexes(cost, labor, area, time, volume, reliability. safety, convenience) to analyze 6 subsystems. The priority of R&D until target year by sub-systems is as follow: 1. Cargo Handing System, 2. Transfer System, 3. Port Entry System, 4. Storage System (Distribution & Manufacturing System included), 5.Inland Transport System, 6.Port Management & Information System.

• 한국컴퓨터산업학회논문지
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• 제8권1호
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• pp.1-8
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• 2007

객체지향기술을 이용하여 소프트웨어를 개발할 때 소위 @큰 그림@ (big picture)으로 나타내는 @design-first@ approach 방식으로 채택하는 하는 경향이 있어 관심을 끌고 있다. 본 연구도 이 방식을 채택하여 video rental store(VRS) system을 개발하였다 이 system은 효과적으로 모델링(modeling) 할 수 있도록 UML을 이용하였으며, PHP script, MySQL Database, Java를 함께 사용하였으며, 실습 프러적트(project)로 구현하였다. 단계별 프로세싱을 통해 학생들이 프로그래밍을 작성하는데 원칙을 따르도록 지도 하였으며, 코딩(coding)을 시작하기 전에, 계획, 분석, 그리고 설계를 이행하도록 지도했다. 학생들이 가능한 실제 세계와 같은 경험을 가지도록 노력했다. 그리고 전반적으로 그 개발과정은 긍정적이었다.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제11권11호
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• pp.5642-5670
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• 2017

Antivirus is an important issue to the security of virtual machine (VM). According to where the antivirus system resides, the existing approaches can be categorized into three classes: internal approach, external approach and hybrid approach. However, for the internal approach, it is susceptible to attacks and may cause antivirus storm and rollback vulnerability problems. On the other hand, for the external approach, the antivirus systems built upon virtual machine introspection (VMI) technology cannot find and prohibit viruses promptly. Although the hybrid approach performs virus scanning out of the virtual machine, it is still vulnerable to attacks since it completely depends on the agent and hooks to deliver events in the guest operating system. To solve the aforementioned problems, based on in-memory signature scanning, we propose an agentless runtime antivirus system VirtAV, which scans each piece of binary codes to execute in guest VMs on the VMM side to detect and prevent viruses. As an external approach, VirtAV does not rely on any hooks or agents in the guest OS, and exposes no attack surface to the outside world, so it guarantees the security of itself to the greatest extent. In addition, it solves the antivirus storm problem and the rollback vulnerability problem in virtualization environment. We implemented a prototype based on Qemu/KVM hypervisor and ClamAV antivirus engine. Experimental results demonstrate that VirtAV is able to detect both user-level and kernel-level virus programs inside Windows and Linux guest, no matter whether they are packed or not. From the performance aspect, the overhead of VirtAV on guest performance is acceptable. Especially, VirtAV has little impact on the performance of common desktop applications, such as video playing, web browsing and Microsoft Office series.

• 한국지능정보시스템학회:학술대회논문집
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• 한국지능정보시스템학회 2001년도 The Pacific Aisan Confrence On Intelligent Systems 2001
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• pp.97-108
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• 2001

Frauds detection is a difficult problem, requiring huge computer resources and complicated search activities Researchers have struggled with the problem. Even though a fee research approaches have claimed that their solution is much better than others, research community has not found 'the best solution'well fitting every fraud. Because of the evolving nature of the frauds. a novel and self-adapting method should be devised. In this research a new approach is suggested to solving frauds in insurance claims credit card transaction. Based on evolutionary computing approach, the method is itself self-adjusting and evolving enough to generate a new self of decision-makin rules. We believe that this new approach will provide a promising alternative to conventional ones, in terms of computation performance and classification accuracy.

• Industrial Engineering and Management Systems
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• 제7권3호
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• pp.266-287
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• 2008

To manage collaborative negotiation in software system design, we have built a socio-technical argument-based negotiation management approach by integrating a Socio-technical Co-construction Process (STCP) with an Argument-based Negotiation Process (ABNP). This paper reviews relevant research work and presents each step of this approach. The STCP provides rich contextual information of technical decisions and social interactions in a system design process. The ABNP provides STCP with a negotiation management and conflict resolution strategy by guiding software engineers to generate, exchange and evaluate their argument claims in negotiation activities. In addition, this paper describes a prototype system which implements this new approach using the advanced Web-based software technologies with the goal of demonstrating how to systematically enhance the negotiation management capabilities in a dynamic socio-technical framework.

• 제어로봇시스템학회논문지
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• 제17권8호
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• pp.777-782
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• 2011

Neural network technique is widely employed in the fields of signal processing, control systems, pattern recognition, etc. Learning of neural networks is an important procedure to accomplish dynamic system modeling. This paper presents a novel learning approach for differential neural network models based on the Kalman-Bucy filter theory. We construct an augmented state vector including original neural state and parameter vectors and derive a state estimation rule avoiding gradient function terms which involve to the conventional neural learning methods such as a back-propagation approach. We carry out numerical simulation to evaluate the proposed learning approach in nonlinear system modeling. By comparing to the well-known back-propagation approach and Kalman-Bucy filtering, its superiority is additionally proved under stochastic system environments.