• The Transactions of the Korea Information Processing Society
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• v.6 no.7
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• pp.1817-1824
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• 1999

How to efficiently and optimally schedule iterative is one of the critical issues in FMC(Flexible Manufacturing Cell). In this paper, we apply transformation rules to find the solution of the scheduling problem in FMC. These kinds of rules have already been applied for the analysis of autonomous Petri nets. Here in, transformation is intended to preserve the existence of at least one optimal solution for the scheduling problem. Some transformations rules to reduced TPN's size without changed the initial characteristics are proposed and applied to analyze the scheduling problem of FMC.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.18 no.6
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• pp.1350-1354
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• 2014

Although there were many activities to provide FMC (Fixed Mobile Convergence) service by several foreign countries such as United States, FMC service could not make a good success for a number of reasons for example, customers indifference and lack of needs. On the other hand, recently FMC is showing its good progress at B2B market in foreign government such as in Germany and US satisfying e-government and BYOD (Bring Your Own Device) needs. This paper studies FMC service of foreign countries and as a result makes a analysis presenting issues for Korean e-government service. Also, we make several suggestions to energize FMC service success.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.6
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• pp.2021-2029
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• 2010

This paper suggested the method to design and analyze FMC robot's dispatching rule using the Simulation and Sequential Patterns. To do this, first of all, we built FMC using simulation and then, extracted signals that facilities call a robot, saved it as the log type. Secondly, we built robot's optimal path using the Sequential Pattern Mining with the results of analyzing the log and relationship between machine and robot actions. Lastly, we adapted it to the A corp.'s manufacturing line for verifying its performance. As a result of applying the new dispatching rule in FMC, total throughput and total flow time decrease because of decreasing material loss time and increasing robot utility. Furthermore, because this method can be applied for every manufacturing plant using simulation, it can contribute to advance total FMC efficiency as well.

• The Journal of Fisheries Business Administration
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• v.23 no.2
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• pp.101-128
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• 1992

How to distribute fisheries catches from producer to consumer is very important for everybody joined fisheries marketing channels (FMC), because most people are influenced their revenue and expenditure through marketing channels. Many institutions in Korea after 1960's have tried to develop the rationalization of FMC, but they have not gotten the satisfactory results in general in spite of a lot fruits. Comparing with general manufacturing industry, the fisheries industry has some specializations in the marketing channels. It makes them unique structure included wholesale market system similiar to fresh (perishable) food market with expertised technology. Wholesale market collects, distributes the fisheries catches and evaluates in by auction or bidding without consideration of producer's opinion. It is very necessary institution to make a decision to equatible price for fresh food and to play an important role for marketing effectiveness with minimum total transation and with massed reserve among institutions. But it has two weak points to increase the marketing cost and to make products bad fresh (perishable). Therefore, both Producer and consumer want to find the direct channels not to pass through wholesale market and to get more profit. I wanted to explain what problems of traditional FMC are and why the direct channel is necessary as follows in this paper. Chapter II : The types and specialization of FMC Chapter III : The structure and problem of fisheries wholesale market channel Chapter IV Marketing cost of FMC and direct channel I suggested when the direct channel in FMC is designed, new planner must carry out marketing functions which are performanced by wholesaler, middle man and the joined members of auction at wholesale market. In view of consumption area, these functions are : (1) the finding of production partner to make a business ; (2) communication of information ; (3) collecting ; (4) distribution ; (5) selecting and grading ; (6) evaluating ; (7) financing and payment ; (8) organization, in view of consumption area. The government must support also the group or individual of new direct channels to succeed it with (1) furnishing of market information (2) supplying of land and facility (3) financing (4) feed-back of dierct channels totally (5) making an opportunity of communication between producer and consumer. I want to emphasize again wholesale market is necessary and important institution for equatible price of fresh food in spite of the its weak points. At the same time. the direct channels are necessary to reduce the marketing cost and to keep better fresh food.

• Journal of the Korean Operations Research and Management Science Society
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• v.20 no.2
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• pp.159-178
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• 1995

Supervisory control is an approach based on formal language. it is used to model and control discrete event systems in which each discrete event process is represented as an automation. A supervisor is a generator that switches control patterns in such a way that a given discrete evenet process behaves in obedience to various constraints. A flexible manufacturing cell (FMC) is one of discrete evenet systems. Functions necessary for the operation of an FMC are characterized by operational components and informational compoments. The operational components can be modeled using the finite state machines and the informational components can be modeled using the abstract formalism which describes supporting operations of the cell controller. In this paper, we addressed function required for FMC control specification, software engineering aspects on FMC control based on supervisory control, a concept of event queue for resolving synchronization problem, and complexity reduction. Based on the mathematical model of an FMC. we synthesized the controller by integrating a supervisor for FMC with control specification that specifies event-driven operation of the cell controller. The proposed control scheme is stable mathematically so that the system always behaves on a controlled way even under the existence of uncontrollable events. Furthermore, using an event queue concept, we can solve a synchronization problem caused by the violation of instantaneity assumption of supervisory control theory in real life situation. And also, we can propotype a control software rapidly due to the modularity of the proposed control scheme.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2013.10a
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• pp.951-952
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• 2013

국내 양돈분야에서의 AI(Artificial Insemination)센터는 인공수정 기술의 개발과 보급과 관하여서는 중추적인 역할을 수행하고 있다. 그러나 현재 전국AI센터에서 사용하고 있는 정보관리 시스템은 독립적이고 운영체제에 의존적인 형태로 운영되고 있다. 따라서 현재 전국AI센터 정보관리 체계는 실시간으로 정보관리 시스템의 접근제한과 모바일 서비스 등의 분야에서 그 분명한 한계를 가진다. 이에 본 논문에서는 유무선 통합(FMC) AI PigMoS(Pig Monitoring System, PigMoS) 시스템을 제안하고 구현하였다. 본 논문에서 제안한 FMC AI PigMoS 시스템은 이동성, 실시간 정보관리 등을 지원할 수 있도록 인터넷과 모바일에서 운영할 수 있도록 구현 하였다. 구현된 FMC AI PigMoS 시스템은 이동성과 실시간 정보관리 등에 필요한 모듈 중심으로 설계하고 구현하였다. 이는 원거리 소비자들에게 각 AI센터에서 생성된 AI정보를 실시간으로 제공하여 개별AI센터의 경쟁력 향상을 높일 것으로 기대한다.

• Nuclear Engineering and Technology
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• v.49 no.1
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• pp.71-81
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• 2017

When an integral pressurized water reactor is operated under low power conditions, once-through steam generator group operation strategy is applied. However, group operation strategy will cause nonuniform coolant flow distribution at the core inlet and lower plenum. To help coolant flow mix more uniformly, a flow mixing chamber (FMC) has been designed. In this paper, computational fluid dynamics methods have been used to investigate the coolant distribution by the effect of FMC. Velocity and temperature characteristics under different low power conditions and optimized FMC configuration have been analyzed. The results illustrate that the FMC can help improve the nonuniform coolant temperature distribution at the core inlet effectively; at the same time, the FMC will induce more resistance in the downcomer and lower plenum.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.19 no.40
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• pp.157-167
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• 1996

공구계획 문제는 FMC의 설계 단계에서 고려되어야만 하는 중요한 요소 중의 하나이다. 본 연구에서는 FMC에서 흔히 사용되는 머쉬닝센터를 대상으로 공구이동정책을 사용할 때 공구의 이동을 최소화할 수 있는 공구계획에 그 목적을 두고 있다. 공구매거진의 제한된 공구수용능력 과 머쉬닝센터 간의 공구이동량을 최소화하여 작업의 공구대기시간을 감소시킴으로써 기계의 이용율을 높이고 생산량을 증대시킬 수 있다. 총공구 수가 주어진 조건하에서 공구의 이동량을 최소화하면서 각 공구의 숫자를 결정하는 수학적 모델을 개발하여 효율적인 해법을 제시하였으며, 실험결과 짧은 시간에 우수한 해를 제공하는 것이 입증되었다.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.17 no.32
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• pp.63-71
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• 1994

The purpose of this paper is to describe an effective cell scheduling system for flexible manufacturing cells. Based on the FMC characteristics, cell scheduling can be defined as a dynamic modified flow shop working in a real-time system. This paper attempt to find the optimal cell scheduling when minimizing the mean flow time for n-job/m-machine problems in static and dynamic environments. Real-time scheduling in an FMC environment requires rapid computation of the schedule.

• Proceedings of the KAIS Fall Conference
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• 2010.11a
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• pp.184-188
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• 2010

현재 FMC 폰을 통해 제공되는 동시착신, 착신전환, 3인통화 등과 같은 다양한 부가서비스가 제공되고 있어 보다 편리하면서도 다양한 기능을 제공하고 있다. 하지만 FMC폰에 적용된 SIP 프로토콜은 송수신 패킷에 대해 쉽게 위변조가 가능하고 송신자 인증기능에 문제점이 발견되고 있어 보안성이 취약하다. 또한 FMC 폰을 이용하여 여러 가지 부가서비스를 이용할 경우 서비스 자체의 취약점을 이용한 공격 등이 가능하다. 따라서 본 연구에서는 현재 상용화 되어 제공되는 SIP기반 주요 VoIP 부가서비스를 대상으로 각각의 Call Flow를 분석하였으며 이를 토대로 각 부가서비스에 대한 취약성에 대해 분석하였다.