• 한국경영과학회지
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• 제22권2호
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• pp.79-97
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• 1997

Many dispatching rules have been developed for the on-line control of product flow in a job shop. The introduction of a flexible manufacturing system (FMS) has added a new requirement to classical job shop control problem : the selection of machines by parts of different types. An FMS can keep a great deal of information on the status of the system, such as information on what is scheduled in the near future, with great accuracy. For example, the knowledge of the time when the next part will arrive at each machine can be neneficial for the routing. This paper tests the effects of the use of this knowledge for part routing on the parts flow time (sum of the time for waiting and service) under a simple routing procedure- a look-ahead routing procedure. A test under many operating conditions shows that the reduction of part flow time from the cases without using this information is between 1% and 11%, which justifies more study on this routing procedure at real production sites when machine capacity is a critical issue. The test results of this paper are also valid for other highly automated systems such as the semi-conductor fabrication plants for routing when the arrivals of parts in the near future are known.

• Journal of information and communication convergence engineering
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• 제6권3호
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• pp.255-260
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• 2008

In the recently years, there has been a big interest in ad hoc wireless network as they have tremendous military and commercial potential. An Ad hoc wireless network is composed of mobile computing devices that use having no fixed infrastructure of a multi-hop wireless network formed. So, the fact that limited resource could support the network of robust, simple framework and energy conserving etc. In this paper, we propose a new ad hoc multicast routing protocol for based on the ontology scheme called inference network. Ontology knowledge-based is one of the structure of context-aware. And the ontology clustering adopts a tree structure to enhance resilient against mobility and routing complexity. This proposed multicast routing protocol utilizes node locality to be improve the flexible connectivity and stable mobility on local discovery routing and flooding discovery routing. Also attempts to improve route recovery efficiency and reduce data transmissions of context-awareness. We also provide simulation results to validate the model complexity. We have developed that proposed an algorithm have design multi-hierarchy layered networks to simulate a desired system.

• 한국통신학회논문지
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• 제38B권11호
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• pp.911-923
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• 2013

무선 센서 네트워크에서 다중경로 라우팅 방안은 종단 간 데이터 전달의 신뢰성을 향상시키기 위한 연구주제 중 하나이다. 최근에는 다중경로의 강건함과 효율성을 위해서 경로의 분리와 관리를 위한 연구가 다수 진행 되었다. 그러나 이전의 연구들은 무선 통신 환경을 고려하지 않은 다중경로의 분리 방법을 이용하고 있다. 게다가, 그들은 불규칙 네트워크 환경에서 노드나 통신 실패로 인해 발생하는 경로 실패를 관리하는 방법이 없거나 추가경로를 생성하는 간단한 방법을 통해 다중경로를 유지한다. 이를 보완하기 위해서, 네트워크 오류지역을 우회 전송하고 경로를 재구성하는 다중경로 유지 방안이 제안되었지만, 중앙 집중적이고 정적인 경로 관리 방법을 이용하기 때문에, 경로 재구성 과정에서 데이터 전달의 중단이나 링크의 단절, 그리고 많은 경로 재구성 비용 등이 요구되는 문제가 있다. 이런 제약과 문제들은 데이터 전달의 신뢰성 저하와 긴급 데이터의 보고 실패로 이뤄질 수 있다. 따라서 본 논문에서는 불규칙적이고 제한적인 무선 센서 네트워크 환경을 고려하여 유연한 분리형 다중경로를 구축하는 방법과 효율적으로 다중경로를 유지할 수 있도록 경로의 우선순위 규칙을 적용한 지역 결정 기반의 다중경로 관리 방법을 제안한다. 그리고 제안 방법의 성능을 평가하기 위해서 시뮬레이션을 수행한다.

• 스마트미디어저널
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• 제11권5호
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• pp.82-90
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• 2022

Along with the growing popularity of 5G technology, providing flexible and personalized network services suitable for requirements of customers has also become a lucrative venture and business key for network service providers. Therefore, dynamic network provisioning is needed to help network service providers. Moreover, increasing user demand for network services meets specific requirements of users, including location, usage duration, and QoS. In this paper, a routing algorithm, which makes routing decisions using Reinforcement Learning (RL) based on the information about link stability, is proposed and called Link Stability aware Reinforcement Learning (LSRL) routing. To evaluate this algorithm, several mininet-based experiments with various network settings were conducted. As a result, it was observed that the proposed method accepts more requests through the evaluation than the past link annotated shorted path algorithm and it was demonstrated that the proposed approach is an appealing solution for dynamic network provisioning routing.

• 한국경영과학회:학술대회논문집
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• 대한산업공학회/한국경영과학회 1992년도 춘계공동학술대회 발표논문 및 초록집; 울산대학교, 울산; 01월 02일 May 1992
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• pp.27-27
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• 1992

• 품질경영학회지
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• 제20권1호
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• pp.136-146
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• 1992

Most of scheduling papers on FMS have been considered that the fabrication process, the machining process and the assembly process etc. are independent and the releasing, routing, dependent, batching, loading problem are treated separetely. In this paper, we discuss that the integrated scheduling problem which can be solved for efficient use. We combine two systems that each process system which in order to produce a product is treated dependently, the releasing and the routing problem are combined one system and we present the efficient flexible manufacturing system as including the alternate process.

• Journal of Communications and Networks
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• 제9권4호
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• pp.383-393
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• 2007

We present a new network-layer architecture that provides generalized addressing. The forwarding infrastructure is independent of the addressing architecture, so multiple addressing architectures can be used simultaneously. We compare our solution with the existing Internet protocols for unicast and multicast services, given the address assignment used in the Internet. By means of an extensive simulation study, we determine the range of parameters for which the overhead costs(delay, state, and network load) of our service are comparable to those of the Internet.

• 대한산업공학회지
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• 제18권1호
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• pp.47-62
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• 1992

This paper describes a procedure for optimizing the route selection and production conditions in alternate process plans under a cellular manufacturing environment. The type of production is mainly production-to-order which deals with unexpected products as the changes factor. The flexible cellular manufacturing can be viewed as a complete unification of both flexible manufacturing process and flexible production management. The integrated problem for designing flexible cellular manufacturing associated with determining the optimal values of the machining speeds, overtime, and intercell flow is formulated as Nonlinear Mixed Integer Programming(NMIP) in order to minimize total production change cost. This is achieved by introducing the marginal cost analysis into the NMIP, which will compute the optimal machining speed, overtime, intercell flow, and routing. The application of this procedure offers greater flexibility to take advantage of the cellular manufacturing due to the optimum use of resources. A solution procedure for this problem was developed and a numerical example is included.

• 산업경영시스템학회지
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• 제23권58호
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• pp.49-58
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• 2000

In order to resolve a deadlock problem in manufacturing systems, three main methods have been proposed-prevention, avoidance, and recovery. The prevention and avoidance methods require predicting deadlocks in advance in order to prohibit them. In contrast, the recovery method allows a system to enter a deadlock state, then resolves it usually using a common buffer. In this paper, a deadlock recovery method considering the impact of flexible job routings is proposed. This method is based on capacity-designated directed graph (CDG) model representing current requesting and occupying relations between Jobs and resources in order to detect a deadlock and then recovers it.

• 정보과학회 논문지
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• 제43권1호
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• pp.1-12
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• 2016

최근, 다양한 인터넷 환경을 제공하는 유연성을 가진 소프트웨어 기반의 라우터 연구가 활발하게 진행되고 있다. 특히, 소프트웨어 라우터에 확장성을 더하기 위해 라우터를 가상화하려는 연구가 증가하고 있다. 하지만, 소프트웨어 라우터를 가상화하면, 가상화로 인한 오버헤드로 인해 성능 저하가 더욱 심화된다. 게다가, 기존의 소프트웨어 라우터에서 제안된 GPU 기반 packet routing 기법들은 native 환경에서의 연구거나 실제 네트워크 상에 적용되지 않은 단점이 있다. 따라서, 기존의 연구로는 GPU routing이 가상 라우터에서 어떤 효과를 보일지를 예측하기 어렵다. 본 논문은 실제로 가상 라우터를 구축하고, 실제 네트워크 패킷을 전송함으로써 가상 라우터에서의 GPU routing의 영향을 보인다. 이를 위해, GPU를 가상화하는 Savanna와 가상 라우터 역할의 Pathfinder를 구현하고, 가상 라우터와 연결된 외부 머신으로부터 패킷을 전송한다.