• 한국경영과학회:학술대회논문집
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• 대한산업공학회/한국경영과학회 1994년도 춘계공동학술대회논문집; 창원대학교; 08월 09일 Apr. 1994
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• pp.236-243
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• 1994

In this paper we consider the part-machine cell formation decision of the generalized Group Technology(GT) problem in which multiple process routes can be generated for each part. The existing p-median model and similarity coefficient algorithm can solve only small-sized or well-structured cases. We suggest an assignment method for the cell formation problem. This method uses an assignment model which is a simple linear programming. Numerical examples show that our assignment method provides good separable cells formation even for large-sized and ill-structured problems.

• 제어로봇시스템학회논문지
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• 제4권6호
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• pp.695-702
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• 1998

In this paper, we propose a novel fault isolation filter design method using the left eigenstructure assignment scheme proposed by Choi et. al., The proposed filter shows good fault isolation performance with exact eigenstructure assignment. An eigenstructure assignment methodology which satisfies the required fault isolation conditions is also proposed. The proposed method guarantees that the corrupted m simultaneous faults can be isolated when the number of available output measurements are (m+1).

• 대한전자공학회논문지
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• 제24권2호
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• pp.215-222
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• 1987

This paper generalizes the previous results of the closed-loop eigenstructure assignment via output feedback in linear multivariable systems. Necessary and sufficient conditions for the closed-loop eigenstructure assignment by output feedback are presented. Some known results on entire eigenstructure assignment are deduced from this results.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제5권1호
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• pp.68-82
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• 2011

Wireless mesh networks (WMNs) provide high-speed backbone networks without any wired cable. Many researchers have tried to increase network throughput by using multi-channel and multi-radio interfaces. A multi-radio multi-channel WMN requires channel assignment algorithm to decide the number of channels needed for each link. Since the channel assignment affects routing and interference directly, it is a critical component for enhancing network performance. However, the optimal channel assignment is known as a NP complete problem. For high performance, most of previous works assign channels in a centralized manner but they are limited in being applied for dynamic network environments. In this paper, we propose a simple flow estimation algorithm and a hybrid channel assignment algorithm. Our flow estimation algorithm obtains aggregated flow rate information between routers by packet sampling, thereby achieving high scalability. Our hybrid channel assignment algorithm initially assigns channels in a centralized manner first, and runs in a distributed manner to adjust channel assignment when notable traffic changes are detected. This approach provides high scalability and high performance compared with existing algorithms, and they are confirmed through extensive performance evaluations.

• International Journal of Naval Architecture and Ocean Engineering
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• 제6권1호
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• pp.162-174
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• 2014

Most shipbuilding scheduling research so far has focused on the load level on the dock plan. This is because the dock is the least extendable resource in shipyards, and its overloading is difficult to resolve. However, once dock scheduling is completed, making a plan that makes the best use of the rest of the resources in the shipyard to minimize any additional cost is also important. Block assignment planning is one of the midterm planning tasks; it assigns a block to the facility (factory/shop or surface plate) that will actually manufacture the block according to the block characteristics and current situation of the facility. It is one of the most heavily loaded midterm planning tasks and is carried out manually by experienced workers. In this study, a method of representing the block assignment rules using a diagram was suggested through analysis of the existing manual process. A block allocation program was developed which automated the block assignment process according to the rules represented by the diagram. The planning scenario was validated through a case study that compared the manual assignment and two automated block assignment results.

• International Journal of Internet, Broadcasting and Communication
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• 제14권1호
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• pp.53-63
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• 2022

In the paper, we propose a TSCH-based scheduling scheme for IEEE 802.15.4e, which is able to perform the scheduling of its own network by avoiding collision from interference network cluster (INC). Firstly, we model a bipartite graph structure for presenting the slot-frame (channel-slot assignment) of TSCH. Then, based on the bipartite graph edge weight, we utilize the Hungarian assignment algorithm to implement a scheduling scheme. We have employed two features (maximization and minimization) of the Hungarian-based assignment algorithm, which can perform the assignment in terms of minimizing the throughput of INC and maximizing the throughput of own network. Further, in this work, we called the scheme "dual-stage Hungarian-based assignment algorithm". Furthermore, we also propose deep learning (DL) based deep neural network (DNN)scheme, where the data were generated by the dual-stage Hungarian-based assignment algorithm. The performance of the DNN scheme is evaluated by simulations. The simulation results prove that the proposed DNN scheme providessimilar performance to the dual-stage Hungarian-based assignment algorithm while providing a low execution time.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2005년도 춘계학술대회 논문집
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• pp.377-382
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• 2005

본 연구에서는 이송장비의 조별운행방식과 Pooling 운행방식에 따른 컨테이너 터미널의 하역시스템 생산성을 비교분석하였다. 기존 컨테이너 터미널에서는 다수의 이송장비가 1개조로 구성되어 하나의 컨테이너 크레인(C/C)에 대해서만 양 ${\cdot}$ 적하작업을 지원하는 고정할당방식을 채택하고 있다. 이러한 할당방식은 하역작업시 혼선이 적고 차량이 일괄적 운행경로를 가지므로 지금까지 매우 광범위하게 적용되어 왔다. 그러나, 각기 다른 조에 편성된 이송장비간에는 상호지원을 하지 않기 때문에 이송장비의 작업융통성이 떨어진다고 볼 수 있다. 이에 비해 본 연구에서는 이송장비의 작업조를 편성하지 않고 투입된 모든 이송장비가 자유롭게 다수의 C/C에 대한 이송작업을 지원할 수 있는 4가지의 동적할당기법을 제시한다. 제시된 4가지의 동적할당은 차량할당시에 C/C의 순번(Se), 대기시간(Qt), 생산성(Pr), 차량할당수(Nv), 버퍼수(Nb)를 고려하는 것으로 연구결과에서 C/C의 현재대기시간, 할당수, 버퍼수를 동시에 고려한 동적할당방식이 가장 효율적이였고, 그 다음으로 할당순서에 기준한 방식이 우수한 결과를 보였다. 그러나, C/C의 현재생산성이나 대기시간만을 고려한 할당방식은 상대적으로 고정할당방식보다 낮은 효율성을 보이는 것으로 나타났다.

• International Journal of Control, Automation, and Systems
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• 제6권6호
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• pp.939-947
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• 2008

The paper proposes a new formulation of the output feedback pole assignment problem. In this formulation, a unified approach is presented for solving the pole assignment problem with various additional objectives. These objectives include optimizing a variety of performance indices, and imposing constraints on the output feedback matrix structure, e.g. decentralized structure. Conditions for the existence of the output feedback are discussed. However, the thrust of the paper is on the development of a convergent pole assignment algorithm. It is shown that when exact pole assignment is not possible, the method can be used to place the poles close to the desired locations. Examples are provided to illustrate the method.

• 한국멀티미디어학회논문지
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• 제12권6호
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• pp.824-832
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• 2009

Multi-radio multi-channel Wireless Mesh Network requires an effective management policy to control the assignment of channels to each radio. We concentrated our investigation on modeling method and solution to find a dynamic channel assignment scheme that is adapted to change of network traffic. Multi-path routing scheme was chosen to overwhelm the unreliability of wireless link. For a particular traffic state, our optimization model found a specific traffic distribution over multi-path and a channel assignment scheme that maximizes the overall network throughput. We developed a simple heuristic method for channel assignment by gradually removing clique load to obtain higher throughput. We also presented numerical examples and discussion of our models in comparison with existing research.

• 대한교통학회지
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• 제8권1호
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• pp.55-71
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• 1990

The behavioral mechanism underlying the traffic assignment model is a choice, or decision-making process of traveling paths between origins and destinations. The deterministic approach to traffic assignment assumes that travelers choose shortest path from their origin-destination pair. Although this assumption seems reasonable, it presumes that all travelers have perfect information regarding travel time, that they make consistently correct decision, and that they all behave in identical fashion. Stochastic user equilibrium assignment relaxes these presumptions by including a random component in traveler's perception of travel time. The objective of this study is to compare "A Model of Deterministic User Equilibrium Assignment" with "Models of Stochastic User Equilibrium Assignment" in the theoretical and practical aspects. Specifically, SUE models are developed to logit and probit based models according to discrete choice functions. The models were applied to sioux Falls net ork consisting of 24 zones, 24 nodes and 76 links. The distribution of perceived travel time was obtained by using the relationship between speed and traffic flow.