• Journal of Korean Society of Industrial and Systems Engineering
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• v.37 no.3
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• pp.89-98
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• 2014

Platform-based product family design is recognized as an effective method to satisfy the mass customization which is a current market trend. In order to design platform-based product family successfully, it is the key work to define a good product platform, which is to identify the common modules that will be shared among the product family. In this paper the clustering analysis using dendrogram is proposed to capture the common modules of the platform. The clustering variables regarding both marketing and engineering sides are derived from the view point of top-down product development. A case study of a cordless drill/drive product family is presented to illustrate the feasibility and validity of the overall procedure developed in this research.

• Journal of Environmental Science International
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• v.13 no.1
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• pp.11-17
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• 2004

The purpose of this study is to present the model of ecological restoration through analysis on the condition of hydrach succession process in brackish water lake. To this study, we investigate and research the present condition of brackish water lake in South Korea. Most brackish water lake in South Korea have characteristics that is come into being malignant hydrach succession. Many lakes were reclaimed to increase foodstuff production. And river conservation work seperate lakes from the ocean. In a embryological view, most lakes based on the brackish water lakes, But present lakes show many different types such as a fresh water lake, a salt lake, a brackish water lake, a swamp, and a marshland. As a result, brackish water lakes have greatly damaged by diverse artificial interventions to promote people's activities. Therefore, in order to manage brackish water lakes systematically, criteria of lake preservation must be coincide with the present conditions of hydrach succession in each lake.

• 유체기계공업학회:학술대회논문집
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• 2000.12a
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• pp.226-235
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• 2000

Two representative finite volume methods, i.e., the time marching method and the pressure correction method, were applied to 8 centrifugal compressor impeller flows, with low to very high level of pressure ratio, among which 7 impellers' experimental performance is given in the open literature. The present study is focused on the prediction differences from both methods, developed by the authors, in the pressure correction method's point of view. In all cases, the time marching method gives a satifactory solution, but the pressure correction method does not. Up to about $18\%$ less level of total-to-total pressure ratio is predicted by the pressure correction method as the level of the impeller pressure ratio increases up to about 10. The drop of total pressure ratio is caused by the underestimation of static pressure rise which seems to be attributed to inappropriate linearization and discretization of the pressure/density coupling terms in the pressure correction equation.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2001.04a
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• pp.363-366
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• 2001

Many joint parts by welding are found in the compression vessels, ship structures, pipings, heat exchangers, etc. Before their welding, steel plate cutting in a required form is very important. But because of the present CAD system's capability, unless otherwise expensive general CAD system is equipped, the efficiency or the accuracy of the cutting work can not be achieved easily. In order to get over this sort of problems, application-specific software that is limited on for the development view of the joint parts in those sort of facilities mentioned before was developed in this study.

• Proceeding of EDISON Challenge
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• 2017.03a
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• pp.376-382
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• 2017

Graphene nanoribbons with zigzag-shaped edge (zGNRs) are predicted to be magnetic insulator at the ground state, attracting significant interest in view of spintronic applications [1]. On the other hand, although they are energetically and thermodynamically more favored than zGNRs [2], graphene nanoribbons with armchair-shaped edge (aGNRs) have been less spotlighted than zGNRs due to the absence of magnetism. Herein, based on the combined density functional theory (DFT) and matrix Green's function (MGF) approach, we consider aGNRs functionalized with various molecular groups, and show that the spin polarizations develop for some of the considered aGNR edge functionalization cases. The origin of the induced magnetism will be discussed within the Lieb's theorem [3]. This work will provide a novel guidance for the development of graphene-based spintronic devices.

• Journal of The Korean Association For Science Education
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• v.10 no.1
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• pp.33-45
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• 1990

To achieve the aim of science education, it is known that warious teaching, and learning materials should have to be used. As a sub-textbook for primary science education, 'Sil Hum-Kwan Chal (Experiment and Observation), teaching and learing material are developed and using now in science. This material have following characteristics; (a) Soruce-book contains reading materials for additional information, various pictures to enririch the science concepts, and supplementary and enrichment activities. (b) Work-book consists of the detailed procedures of activities of experiments presented in the textbook, student can record the experimental procedures and results. (c) Operational manuals provide operation techniques for experimental equipments which are used in science class. In this study the using status are surveyed for the 3rd grade of primary school, and based on this survey the improvement plan are discussed in view of design, quantity and utility, of sub-textbook.

• Proceedings of the Korean Geotechical Society Conference
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• 2008.10a
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• pp.549-558
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• 2008

Well known and widely used in urban area and limited installation condition, a low noise and vibration piling method which has being called Bored Prefabricated Piling Method was reviewed in terms of design guide, and introduced a few case as well. Among the areas being applied of that method, a structural guide of architectural foundation was reviewed and compared to civil engineering foundation area to provide wider information for the foundation engineers. With introducing a few case application including pile load testing review especially dynamic testing in normal building foundation work, engineers may have a useful information on the design and construction of the piling method even different engineering area. It may also make enhancement a view of foundation engineering knowledge to various pile foundation area.

• Journal of Institute of Control, Robotics and Systems
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• v.12 no.11
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• pp.1102-1110
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• 2006

This paper addresses the problem of computing grasp stability of the object for two-fingered robots in two dimensions. The concepts of force-closure and dual space are introduced and discussed in novel point of view, and we transform friction cones in a robot work space to line segments in a dual space. We newly define a grasp stability index by calculating intersection condition between line segments in dual space. Moreover, we propose a method to find the optimal grasp points of the given object by comparing the defined grasp stability index. Its validity and effectiveness are investigated and verified by simulations for quadrangle object and elliptic objects.

• Journal of the Korean Institute of Telematics and Electronics C
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• v.34C no.6
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• pp.1-10
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• 1997

By considering low power design at higher levels of abstraction rather than at lower levels of abstraction, we can apply various transformation techniques to a system design with wider view and obtain much more effective power reduction with less cost and effort. In this paper, a transformation technique, called power - conscious loop folding is proposed for high level synthesis of a low power system.Our work is focused on reducing the power consumed by functional units in adata path dominated circuit through the decrease of switching activity. Te transformation algorithm has been implemented and integrated into HYPER, a high level synthesis system for experiments. In our experiments, we could achieve a pwoer reduction of up to 50% for data path dominated circuits.

• IE interfaces
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• v.14 no.1
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• pp.59-66
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• 2001

This paper introduces the case study that has been performed at the block paint shop, Hyundai Heavy Industries. First of all, the overall production processes of shipbuilding and research activities conducted by Korean are reviewed with a view-point of production planning. Then HYPOS(Hyundai heavy industries Painting shop Operation System) project is briefly described, which has several modules such as planning module, scheduling module, work order module, and DB(database) management module. Although the HYPOS system has several modules, this paper mainly focuses on the planning module that utilizes the rough-cut simulation algorithm to make a decision about the policy for production schedule. The HYPOS has been operated since June, 2000 and the operation data has been collected for the purpose of future evaluation about the performance of HYPOS system. The evaluation of HYPOS will be shown in a public domain as soon as the enough operation data is available.