• Proceedings of the KIEE Conference
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• 1998.07c
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• pp.1231-1234
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• 1998

Design & Operation of power system for meeting increase of electric power demand is becoming more difficult and complex. One of reasons is increase of fault current. As one of the most effective methods for suppressing the fault current, installation of SFCL is expected. This paper describes a method of fault analyses of power system with SFCLs, and also discusses determination of specification of SFCLs, effects of limiting the fault current due to SFCLs by use of the model system of two - bus electric power system with parallel circuit model transmission line. Also, describes the definition of six specific parameters of SFCL for power system application & a proposal of design method of specific parameter of a resistance type SFCL in overhead transmission lines considering operation of protective relays.

• Journal of the Korea Institute of Building Construction
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• v.8 no.3
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• pp.119-125
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• 2008

The volume of material and number of workers mobilized has been on the rise in line with the domestic projects getting higher, larger and complex currently. Particularly for the project in downtown, delivering the resources in timely manner is very crucial in carrying out the overall project as scheduled. Inappropriate lifting plan often causes inefficiency over the entire project, resulting in increase in schedule and cost. Despite of such importance of lifting plan for architectural work, lifting plans at the most of domestic projects, except a few cases for large scale high-rise buildings, have been heavily dependent on engineer's personal experience and intuition alone. To deal with such problems, the study was intended to develop and suggest a systematic and objective process for determining the lift, categorizing the lifting equipment into the two types, one for workers and another for material.

• Journal of applied mathematics & informatics
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• v.11 no.1_2
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• pp.1-57
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• 2003

Vector fields in three-space admit bundles of internal variables such as a Heisenberg algebra bundle. Information transmission along field lines of vector fields is described by a wave linked to the Schrodinger representation in the realm of time-frequency analysis. The preservation of local information causes geometric optics and a quantization scheme. A natural circle bundle models quantum information visualized by holographic methods. Features of this setting are applied to magnetic resonance imaging.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.10 no.6
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• pp.39-45
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• 2011

Due to the introduction of the electronic control systems, agricultural machine is getting complicated with its special function. The complex electronics system increases difficulty of maintenances in the wiring harness system. The heavy wiring harness has some poor reliability and workability in the production line of manufacture also. So, in this study, some small local control modules are developed to complement the difficulties with the benefits of distributed control system. All of the local control modules are connected by using CAN communication. This system developed this study has the advantages of modification or alteration of wiring and local modules. All the sensors and actuators can be easily monitored and controlled by the main controller with the appropriate communication protocol made by in this study.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.13 no.12
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• pp.1288-1296
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• 2001

A scheme for on-line fault detection and diagnosis of an air-handling unit is presented. The fault detection scheme uses residuals which are generated by comparing each measurement with analytical redundancies computed from the reference models. In this paper, artificial neural networks (ANNs) are used to estimate analytical redundancy and to classify faults. The Lebenburg-Marquardt algorithm is used to train feed forward ANNs that provide estimates of continuous states and diagnosis results. The simulation result demonstrated that the ANNs can effectively detect and diagnose faults in the highly non-linear and complex HVAC systems.

• Journal of Plant Biology
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• v.36 no.2
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• pp.141-149
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• 1993

Comparative morphology of winter buds of 16 species of gymnosperms which belong to six families and 13 genera was investigated. All the species examined except Taxaceae had bracts and ovuliferous scales in female buds, and the bract was fused with ovuliferous scale in various degrees. Comparison of the modern conifers with fossil ones in the position of ovule and structure of bract-scale complex suggested that Taxaceae should be placed in Coniferales, rather than treating as a distinct order. The disposition of bract surrounding the ovules of Cephalotaxus and Torreya indicated that the origin, of ovules had separate evolutionary line in spite of similar structure of female bud. The shape of microsporophyll in male bud was diverse among the species. The dehiscence of microsporangium was transverse in Abies and Tsuga, while longitudinal in other species. Descriptions and key to the species based on bud morphology were provided.

• Proceedings of the IEEK Conference
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• 2007.07a
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• pp.251-252
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• 2007

The thesis proposed the Text Extraction Algorithm which is a text extraction algorithm which uses the Coiflet Wavelet, YCbCr Color model and the close curve edge feature of adaptive LoG Operator in order to complement the demerit of the existing research which is weak in complexity of background, variety of light and disordered line and similarity of text and background color. This thesis is simulated with natural images which include naturally text area regardless of size, resolution and slant and so on of image. And the proposed algorithm is confirmed to an excellent by compared with an existing extraction algorithm in same image.

• Publications of The Korean Astronomical Society
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• v.30 no.2
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• pp.375-379
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• 2015

Planetary nebula in elliptical galaxies pose a problem in dark matter theory. Using data from the Planetary Nebula Spectrograph (PN. S), Romanowsky et al. (2003) reported that less dark matter than expected was found within 5 to 6 effective radii of three elliptical galaxies. We attempt to explain similar observations of elliptical galaxies with MOdified Newtonian Dynamics (MOND). We collect 16 elliptical galaxies with planetary nebulae from the public web data of PN. S. We investigate the dynamical behavior by analyzing the line-of-sight velocity dispersion in the framework of MOND.

• International Journal of CAD/CAM
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• v.2 no.1
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• pp.45-54
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• 2002

Given a set of three generator circles in a plane, we want to find a circumcircle of these generators. This problem is a part of well-known Apollonius' $10^{th}$ Problem and is frequently encountered in various geometric computations such as the Voronoi diagram for circles. It turns out that this seemingly trivial problem is not at all easy to solve in a general setting. In addition, there can be several degenerate configurations of the generators. For example, there may not exist any circumcircle, or there could be one or two circumcircle(s) depending on the generator configuration. Sometimes, a circumcircle itself may degenerate to a line. We show that the problem can be reduced to a point location problem among the regions bounded by two lines and two transformed circles via $M{\ddot{o}}bius$ transformations in a complex space. The presented algorithm is simple and the required computation is negligible. In addition, several degenerate cases are all incorporated into a unified framework.

• The Research Journal of the Costume Culture
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• v.16 no.2
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• pp.369-381
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• 2008

The objectives of this study are to observe the theoretical background of brand extension, to compare & analyze the cases of brand extension in Domestic and abroad based on the existing studies to present the characteristics of brand extension strategies, and to contribute to the establishment of marketing strategies of brand portfolio for the globalization of national brands. As for the methods of research, literature review and case study were combined. As a result of the case analysis, fashion business possessing a lot of brands have powerful competitiveness when they consider the brands as one unit and manage them with definition and insight to produce mutual synergy. Given that brand environment is being complicated and diversified with market segmentation, brand extension, various product groups, numbers of competitors, and complex distribution structure, the hierarchical structure of brand may have even more significance as a strategy.