• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2008년도 하계종합학술대회
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• pp.20-21
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• 2008

In the IEEE 802.16 Wireless MAN standard, the best effort service class is ranked on the lowest position in priority so that only scarce resource may be available for it. Also, the best effort service is usually assisted by a MAC scheme based on reservation ALOHA without explicit acknowledgement. However, the standard only specifies the skeleton of the MAC scheme. In this paper, we propose some rules to specify the indefinite part of the MAC scheme as well as to improve the throughput and delay performance of the MAC scheme. As generic rules for demanding and granting resource, we first propose non-gated exhaustive, gated exhaustive, non-gated limited, and gated limited demand rules, and deficient and full grant rules. Secondly, we propose grant regulation rules, identified as replacement and lifetime rules, to avoid excessive grant incurred by not giving acknowledgement. Noting the residual resource is inflated by adopting a grant regulation rule, we finally propose a rule for investing the residual resource to a subscriber station. Simulation results confirm that a combination of proposed rules improves the performance of the MAC scheme.

• Industrial Engineering and Management Systems
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• 제2권1호
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• pp.9-27
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• 2003

In a wafer fabrication factory, the completion time of an order is affected by many factors related to the specifics of the order and the status of the system, so is difficult to predict precisely. The level of influence of each factor on the order completion time may also depend on the production system characteristics, such as the rules for releasing and dispatching. This paper presents a method to identify those factors that significantly impact upon the order completion time under various combinations of scheduling rules. Computer simulations and statistical analyses were used to develop effective due date assignment models for improving the due date related performances. The first step of this research was to select the releasing and dispatching rules from those that were cited so frequently in related wafer fabrication factory researches. Simulation and statistical analyses were combined to identify the critical factors for predicting order completion time under various combinations of scheduling rules. In each combination of scheduling rules, two efficient due date assignment models were established by using the regression method for accurately predicting the order due date. Two due date assignment models, called the significant factor prediction model (SFM) and the key factor prediction model (KFM), are proposed to empirically compare the due date assignment rules widely used in practice. The simulation results indicate that SFM and KFM are superior to the other due date assignment rules. The releasing rule, dispatching rule and due date assignment rule have significant impacts on the due date related performances, with larger improvements coming from due date assignment and dispatching rules than from releasing rules.

• 대한산업공학회지
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• 제32권2호
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• pp.82-90
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• 2006

Reconfigurability of machine tools is one of the critical factors to realize the responsive manufacturing systems to satisfy the mass customization production. This paper presents the methods to model the reconfigurable machine tools (RMTs) on Internet in response to change in the machining requirements. Specifically, the structure and motion model of machine tools using module combination rules and connectivity graph are developed. And we developed Internet-based simulator for designing of RMTs (ISD-RMT). In response to the user requirements, various structures of RMTs can be derived using the module combination rules and connectivity graph relationships. In addition, the user can verify generating structures through the control and simulation procedures.

• 환경영향평가
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• 제4권2호
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• pp.29-37
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• 1995

The national park should be preserved in accordance with the regulation, but the development planning or facilities management planning has not been faithful to the spirits of the regulation. Recently natural environment has been radically changed, and especially damaged by large scale development of Service Facilities Zone. Thus the effective land use planning of the national park is required. Therefore, the purpose of this study is to propose the alternative site for The Second Service Facilities Zone in Mt. Kyeryong National Park using the GIS, and to compare the alternative site with the existing development site. Site selection was based on Rules of Combination which covers topographic analysis, viewshod analysis, distance analysis from hot spring well, land use analysis, and forest stand analysis.

• 한국철도학회논문집
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• 제8권5호
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• pp.411-418
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• 2005

This paper expounds the development of a user-friendly expert system for the optimal stacking sequence design of composite laminates subjected to the various rules constraints. The expert system was realized in the graphic-based design environment. Therefore, users can access and use the system easily. The optimal stacking sequence is obtained by means of integration of a genetic algorithm, finite element analysis. These systems were integrated with the rules of design heuristics under an expert system shell. The optimal stacking sequence combination for the application of interest is drawn from the discrete ply angles and design rules stored in the knowledge base of the expert system. For the integration and management of softwares, a graphic-based design environment that provides multi-tasking and graphic user interface capability is built.

• 한국컴퓨터정보학회논문지
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• 제1권1호
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• pp.159-170
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• 1996

본 논문 에서는 진화 알고리즘과 퍼지 제어기를 이용하여 비선형 시스템을 위한 최적 규칙들을 자동으로 생성하는 방법을 제안한다. 진화 알고리즘에 의한 퍼지 논리 시스템의 최적 규칙은 전문가의 사전 경험이나 지식이 없이도 자동 설계가 가능하고 이들 규칙을 이용하석 지능 제어를 할수 있다. 본 논문에서 사용한 접근 방법은 최지 규칙 소속 함수의 자농 조정으로 규칙을 생성하고. 최적의 제어 규칙 탐색은 퍼지 논리 시스템의 성능 기준으로 정의한 적합도 값을 기반으로 탐색한다. 제안한 방법의 유용성을 보이기 위해 )fl선형 시스템에서 컴퓨터 모의실험을 행하였다.

• 한국해양공학회지
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• 제21권6호
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• pp.115-119
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• 2007

Inference rules of the knowledge base, generated by experts or optimization, may be often inconsistent and incomplete. This paper suggests a systematic and automatic method which extracts inference rules not from experts' subject but from data. First, input/output linguistic variables are partitioned into several properties by the fuzzy equalization algorithm and each combination of their properties comes to premise of inference rule. Then, the conclusion which is the mast suitable for the premise is selected by evaluating consistent measure. This method, automatically from data, derives inference rules from experience. It is shown through application that extracts new inference rules between hull dimensions and hull performance.

• 호남수학학술지
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• 제41권1호
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• pp.35-49
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• 2019

In this work, it is shown that the combination of operational techniques and the use of the principle of quasi-monomiality can be a very useful tool for a more general insight into the theory of matrix polynomials and for their extension. We explore the formal properties of the operational rules to derive a number of properties of certain class of matrix polynomials and discuss the operational links with various known matrix polynomials.

• 한국지능시스템학회:학술대회논문집
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• 한국퍼지및지능시스템학회 1993년도 Fifth International Fuzzy Systems Association World Congress 93
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• pp.1266-1269
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• 1993

The paper introduces a new method for fuzzy processing. The method allows handing a piece of information lost in the classic fuzzification process, and thus neglected by other methods. Processing the result after fuzzification is sustained by the interpretation that the input-output set mapping, specified by the IF-THEN rules, can be regarded as a direct mapping of their corresponding alpha-cuts. Processing involves just singletons as intermediary results, the final result being a combination of singletons obtained from fired rules.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2001년도 ICCAS
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• pp.96.2-96
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• 2001

This paper presents a control method for the experimental mobile vehicle. By merging the advantages of neural network, adaptive and fuzzy control, neural network-based adaptive fuzzy control is proposed. It can deal with a large amount of training data by neural network, from these data producing more accurate fuzzy rules by adaptive control, and then controlling the object by fuzzy control. This is not the simple combination of the three methods, but merging them into one control system Experiments and some future considerations are given.