• The Journal of Information Technology and Database
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• v.1 no.1
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• pp.63-81
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• 1994

The trigger mechanism in active object-oriented database systems is known to be a good tool for describing user-defined integrity constraints. It cannot adequately support, however, certain integrity constrains specified on the objects in class composition hierarchy. Those are the cases where the constraints must be maintained in the forward direction along the composition hierarchy as well as in the backward direction We call theses kinds of problems "backward propagation problem" and investigate several ways to resolve them using the currently available techniques. Based on them, a new constructor, called CONSTRAIN $T^{cch}$, is proposed. The constructor can be realized with enhanced facilities for active OODBMS which we recommend in this paper.d facilities for active OODBMS which we recommend in this paper.r.

• Journal of Ocean Engineering and Technology
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• v.15 no.4
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• pp.108-114
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• 2001

Petri nets have been introduced as a powerful analyzing and design tool for the discrete systems such as sequential control systems. However, one of the important problems in its applications is that the model can be analyzed hardly when we deal with large scale systems because of increase of the number of Petri net components. To overcome this problem, some methods for dividing or reducing of Petri net have been suggested. In this paper, an approach for hierarchical expression of Petri net based on Sequential function Chart(SFC) and Bottom Up oriented Mehodology(BUM) is proposed. Especially, some definitions and rules are defined in order to divide and compose sub Petri nets. A measuring tank system will be described as a typical kind of discrete systems and modeled by some sub Petri nets based on the SFC and BUM by the proposed method in this paper.

• Proceedings of the KIPE Conference
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• 2000.07a
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• pp.18-21
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• 2000

A nonconstact technique for reducing the core loss of a grain oriented silicon steel has been developed by the use of mechanical scribing Q-switched laser plasma jet or electron beam irradiation. Among these methods electron beam irradiation has advantages of domain refining without any deformation or damage of insulating film on the surface of a grain criented Si-Fe. Over the past years this processing was performed in vaccum of 10-4 Torr or below causing the problem of high cost and difficulty of continuous works. In this paper a miniature electron permeable window through which electron beam energy 4-80keV and average current 0.1-2mA. were obtained for electron beam irradiating on air was designed and manufactured.

• Journal of the Korean Institute of Landscape Architecture
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• v.25 no.3
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• pp.143-154
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• 1997

The fundamental concept of shared street is integration of traffic and pedestrian activity as a positive principle for street planning. Shared streets have been very successful in several countries in terms of reductions in traffic accidents, increased social interaction and children's play, and a high degree of satisfaction by the residents. This paper proposes the concept of shared street to solve traffic problem without reorganizing traditional street structure and without disturbing traditional function of street as a living space for residents. And this study examines detail concepts and techniques of the shared street and applies them to a pedestrian oriented streetscape design of "Ducksugung-Gil," Seoul, which was one of the most important streets in Korean modernization history.n history.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.8 no.5
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• pp.1028-1034
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• 2004

As use of internet generalized laying stress on WWW(World Wide Web) service of multimedia based recently, we could acquire many informations that exist to all over the world's computer network. It is risen to important problem that use of internet acquires correct information rapidly on modem society which is generalized. This paper designed internet search engine and understand structure of that drawing URL which is optimized, and secure embodiment technology using OOPL(Object-Oriented Programming Language). Also, compare with existent domestic manufacture search engines and system that propose showed that the bad link rate is improved in this paper.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.18 no.8
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• pp.1176-1189
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• 1993

This paper presents the Multiple Keyword Retrieval Method under the Object-Oriented Multimedia Database Model. The multiple keyword registration and retrieval algorithms are developed to reduce the partial matching problem in multimedia data retrieval. For this, proper storage structures of the lookup tables are designed. And also, in order to maintain the constant retrieval time, media data files are organized with B+ tree structure.

• The Research Journal of the Costume Culture
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• v.6 no.1
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• pp.121-135
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• 1998

This study discusses the concept on environment-friendly textile products, environmentally oriented processes of fiber and fabric production, and case reports of environments-friendly products. This study may inspire recognition and necessity of environment-friendly textile products to textile industry and designers ,and also develop the consideration of environmental aspects in the field of textile design and fashion design. Environment-friendly textile products mean not only natural products but also the products reduced the environmentally harmful consequences of their production processes. Because the textile production processes may cause environmental problem. the processes of bleaching, dyeing, mercerising, proofing, and establishing must be carefully controlled. These environment-friendly textile products in this study are divided into development of environment-friendly textile products, recycled textile products, products which are produced by environmentally oriented processes, and recycling capacity in the process of the coming into use. If the textile industrialists and its designers are continuously interested in those environment-friendly products, the textile industrialists produce environment-friendly products in manufacturing process, and the textile and the fashion designers design their products having the conciousness of environment. They reduce environmental pollution caused by producing textile products and are survived in the struggle of existence of the future world trade market.

• 제어로봇시스템학회:학술대회논문집
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• 1992.10a
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• pp.332-336
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• 1992

We describe about the graphic simulation system which supports the determination of efficient multi-robot motions during cooperation. For the construction of the simulation software for multi-robot motions, two problems are presented. First problem is that all the robot motions must be determinded using both the desired object motions and the holonomic constraints with the object. To find the robot motions combined with the various object motion path, the robot motions are derived from the desired object path instead of a master robot path. Therefore robot motions can be easily modifiable with the various object motions. This type of motion determination is different from that of the master-slaves method using the master robot motions. The other is that the developments of robot application softwares need a heavy cost when the participated robots or the tasks given to the robots are changed. Based on object-oriented programming paradigm, we present useful software objects describing robot application programming environment. The object-oriented programming paradigm increases the software reusability, reliability, and extensibility, and also provides the structual concepts to cope with the various demands of robot application programming.

• Journal of the Korean School Mathematics Society
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• v.3 no.2
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• pp.155-164
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• 2000

The future society will demand that enables one to solve in many fields by connecting various informations in many fields and then creating his own information. In the coming society, creativeness will be regarded much important. This ability can be developed with materials through group activities experimental class in math classes. This classes using these materials are not teacher-oriented, explanatory classes but student-oriented ones. They offer students opportunities to think by themselves and expand their potential abilities. They are suitable for rising and keeping student's interests. Therefore experimental classes through group activities enable students to think mathematically and make them recognize the importance of mathematical approach by letting them work connecting other subjects or things in real life. They can develop not only expressive, communicative ability and cooperative spirit, but also the ability to transcend the class itself and then reorganize facts in new insights. Besides, math classes with experiments can arouse student's curiosity familiarizing them with mathematics. Moreover, they can expand student's originative and problem-solving abilities.

• Journal of the Korean Society for Precision Engineering
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• v.22 no.2
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• pp.70-78
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• 2005

In this paper, a novel rotor flux estimation method of an induction motor using support vector regression(SVR) is presented. Two well-known different flux models with respect to voltage and current are necessary to estimate the rotor flux of an induction motor. Training of SVR which the theory of the SVR algorithm leads to a quadratic programming(QP) problem. The proposed SVR rotor flux estimator guarantees the improvement of performance in the transient and steady state in spite of parameter variation circumstance. The validity and the usefulness of proposed algorithm are throughly verified through numerical simulation.