• Journal of Korean Institute of Industrial Engineers
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• v.31 no.1
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• pp.20-26
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• 2005

This paper proposes the heuristic algorithm for the generalized GT problems to consider the restrictions which are given the number of machine cell and maximum number of machines in machine cell as well as minimum number of machines in machine cell. This approach is split into two phase. In the first phase, we use the similarity coefficient which proposes and calculates the similarity values about each pair of all machines and sort these values descending order. If we have a machine pair which has the largest similarity coefficient and adheres strictly to the constraint about birds of a different feather (BODF) in a machine cell, then we assign the machine to the machine cell. In the second phase, we assign parts into machine cell with the smallest number of exceptional elements. The results give a machine-part grouping. The proposed algorithm is compared to the Modified p-median model for machine-part grouping.

• Journal of the Korean Operations Research and Management Science Society
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• v.16 no.2
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• pp.137-137
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• 1991

This paper compares and evaluates the performances of the two types of mathematical programming models for solving the machine-part cell formation problem in group technology manufacturing : indirect formulation relying on surrogate measure such as similarity coefficient and direct formulation seeking to minimize the number of exceptional elements. New indirect formulation, called the generalized p-median model. is proposed. Unlike existing p-median formulations, proposed formulation includes the classical cell formation problem in which only one process plan exsits for each part as a special case. The proposed new formulation can also deal with the cell formation problem in which alternative process plans exist for a part. The indirect formulation is compared with a new direct formulation which needs much fewer extra variables and constraints than existing direct formulations. Some significant findings from comparative experiment are discussed.

• The Transactions of the Korean Institute of Electrical Engineers D
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• v.51 no.3
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• pp.100-107
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• 2002

In this paper, we propose an expert system for electronic interlocking which enhances the safty, efficiency and expanability of the existing system by designing real-time interlocking control based on the interlocking table automatically generated using artificial intelligence approach. The expert system consists of two parts; an interlocking table generation part and a real-time interlocking control part. The former generates automatically the interlocking relationship of all possible routes by searching dynamically the station topology which is obtained from station database. On the other hand, the latter controls the status of station facilities in real-time by applying the generated interlocking relationship to the signal facilities such as signal devices, points, track circuits for a given route. The expert system is implemented in C language which is suitable to implement the interlocking table generation part using the dynamic memory allocation technique. Finally, the effectiveness of the expert system is proved by simulating for the typical station model.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2000.11a
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• pp.267-271
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• 2000

A part definition must not only provide shape information of a nominal part but also contain non-shape information such as tolerances, surface roughness and material attributes. Although machining features are useful for suitable shape information for process reasoning in the CAPP, they need to be integrated with tolerance information for effective process planning. We develop the tolerance modeler that efficiently integrates machining features with tolerance information for feature-based CAPP It is based on the association of machining features, tolerance features. and tolerances Tolerance features, where tolerances are assigned, are classified into two types; one is the face that is a topological entity on a solid model and the other is the functional geometry that is not referenced to topological entities. The functional geometry is represented by using machining features All the data for representing tolerance information with machining features are stored completely and unambiguously in the independent tolerance structure. The developed tolerance modeler is implemented as a module of a comprehensive feature-based CAPP system.

• International Journal of Quality Innovation
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• v.9 no.1
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• pp.55-67
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• 2008

Following this introduction, this paper presents two conceptual and theoretical analyses-(i) CSR and its relation to profit and charity (ii) CSR as part of a service business model. The paper then illustrates these concepts using a comparative study of four service firms, with particular emphasis on their different CSR activities and how these affect the mission of each company. All four of the service companies are global actors with strong Service Brands (Edvardsson, Enquist and Hay, 2006) and a leading position in using CSR as a driving force for doing business: IKEA, Starbucks, H&M and the Body Shop. The paper then draws together the conceptual analysis and the case studies in a discussion of how CSR can be a proactive driver in the service business. Because of the limit space for a QMOD paper the focus is on the conceptual and theoretical analysis part and the empirical part and discussion/conclusion has to be further developed.

• 제어로봇시스템학회:학술대회논문집
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• 1988.10b
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• pp.973-980
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• 1988

This two-part paper presents a control method that allows for stable interaction of a robot manipulator with the environment. In part 1, we focus on the input ouput relationships (unstructured modeling) of the robot and environment dynamics. This analysis leads to a general condition for stability of the robot and environment taken as a whole. This stability condition, for stable maneuver, prescribes a finite sensitivity for robot and environment where sensitivity of the robot(or the environment) is defined as a mapping forces into displacement. According to this stability condition, smaller sensitivity either in robot or in environment leads to narrower stability range. In the limit, when both systems have zero sensitivity, stability cannot be guaranteed. These models do not have any particular structure, yet they can model a wide variety of industrial and research robot manipulators and environment dynamic behavior. Although this approach of modeling may not lead to any design procedure, it will allow us to understand the fundamental issues in stability when a robot interacts with an environment.

• Proceedings of the Korean Information Science Society Conference
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• 1999.10c
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• pp.783-785
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• 1999

Distributed Object Systems are very complex. So, it is difficult to see overall relationship among objects participated in the system. Moreover the performance tuning or maintenance are also important issues of it. So, it needs a way to view the system with low-cost and an efficient method. One of solutions is a visualization tool or system. In this paper, we proposed a tracing facility for Java-based distributed object system, especially RM(Remote Method Invocation). Our up-coming visualization system will use two phase hybrid post-mortem/on-the-fly technique. To support it, the fundamental tracing part must have some flexible and dynamic mechanism. The main idea of our tracing technique is the Plug-in Sensor Model(PSM). The relationship between tracing (monitoring) part and visualization part is closely related. So, we considered the appropriate factors for visualization. We developed 'Traced RMI(TRMI)'. For more precise visualization of a working system, the casuality of events has to be preserved. TRMI can support global event ordering.

• Korean Management Science Review
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• v.16 no.2
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• pp.137-147
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• 1999

This paper compares and evaluates the performances of the two types of mathematical programming models for solving the machine-part cell formation problem in group technology manufacturing : indirect formulation relying on surrogate measure such as similarity coefficient and direct formulation seeking to minimize the number of exceptional elements. New indirect formulation, called the generalized {{{{ { p}_{ } }}-median model. is proposed. Unlike existing {{{{ { p}_{ } }}-median formulations, proposed formulation includes the classical cell formation problem in which only one process plan exsits for each part as a special case. The proposed new formulation can also deal with the cell formation problem in which alternative process plans exist for a part. The indirect formulation is compared with a new direct formulation which needs much fewer extra variables and constraints than existing direct formulations. Some significant findings from comparative experiment are discussed.

• Wind and Structures
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• v.4 no.4
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• pp.315-332
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• 2001

Presented herein is a numerical study for evaluating the aerodynamic behaviour of equipped bridge deck sections. In the first part, the method adopted is described, in particular concerning turbulence models, meshing requirements and numerical approach. The validation of the procedure represents the aim of the second part of the paper: the results of the numerical simulation in case of two-dimensional, steady, incompressible, turbulent flow around a realistic bridge deck are compared to the data collected from wind-tunnel tests. In order to demonstrate the influence of the section details and of the partial streamlining of the deck geometry on its aerodynamic behaviour, in the third part of the paper the effect of the fairings and of each item of equipment of the section (such as central barriers, side railings and sidewalks) is evaluated. The study has been applied to the deck section of the Normandy cable-stayed bridge.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.38 no.11
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• pp.941-949
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• 1989

This two-part paper presents a control method that allows for stable interaction of a robot manipulator with environment. In part 1, we focus on the input output relationships (unstructured modeling) of the robot and environment dynamics. This analysis leads to a general condition for stability of the robot and environment taken as a whole. This stability condition, for stable maneuver, prescribes a finite sensitivity for robot and environment where sensitivity of the robot (or the environment) is defined as a mapping forces into displacement. According to this stability condition, smaller sensitivity either in robot or in environment leads to narrower stability range. In the limit, when both systems have zero sensitivity, stability cannot be guaranteed. These models do not have any particular structure, yet they can model a wide variety of industrial and research robot manipulators and environment dynamic behavior. Although this approach of modeling may not lead to and design procedure, it will allow us to understand the fundamental issues in stability when a robot interacts with an environment.