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A Study On Database Improvement Of The Power System Protection Program (계통보호 정정 프로그램의 데이터베이스 개선에 관한 연구)

  • Kim, S.H.;Lee, S.J.;Choi, M.S.;Min, B.U.
    • Proceedings of the KIEE Conference
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    • 2002.11b
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    • pp.193-195
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    • 2002
  • This paper presents the methods to solve the problem about Power System Protection Program(PROSET) and describe the database relation and schema with UML. PROSET is a overall program system to protect power system and correct it. In the context of the PROSET it is so difficult to edit database data when topology is changed. When the renewal of data is performed. all changed values are disappeared. Therefore, it will not be expected to know the present situation by using the information of the databases data. So it is necessary to solve this problem. Solution is copy of the user. Only E.R diagram is used to express database schema and relation. So, in this paper, UML(Unified Modeling Language) will be used to express PROSET and database of MCD-H and MDT-H.

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Effects of Ni addition on continuous cooling transformation behavior of low carbon HSLA steels (저탄소${\cdot}$저합금 강의 연속 냉각 변태에 미치는 Ni의 영향)

  • Kang J. S.;Jun J. H.;Park C. G.
    • Proceedings of the Korean Society for Technology of Plasticity Conference
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    • 2005.10a
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    • pp.456-459
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    • 2005
  • Continuous cooling transformation behaviors were studied fur low carbon HSLA steels containing three different level $(1\~3\;wt\%)$ of Ni addition. Thermo-mechanical processing (TMP) simulations to construct continuous cooling (CCT) diagram were conducted by using Gleeble system. As cooling rate increased, pearlite, granular bainite, acicular ferrite, bainitic ferrite and lath martensite were transformed from deformed austenite. Fully bainitic microstructure were developed at all cooling rate condition in high Ni containing steel due to hardenability increasing effects of Ni. Ni also influenced the transformation kinetics. At the slowest cooling rate of $0.3^{\circ}C/s$, transformation delayed with decreasing Ni contents because of the diffusion of substitutional alloy elements. However, cooling rate slightly increased to $1^{\circ}C/s$, transformation kinetics accelerated with decreasing Ni contents because nucleation of bainite was sluggish due to hardening of residual austenite.

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A Development of Expert System for Secondary School's Interior Space Function Analysis (중학교의 내부공간 기능분석을 위한 전문가 시스템 개발)

  • Kim, Myoung-Whan
    • The Journal of Sustainable Design and Educational Environment Research
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    • v.2 no.2
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    • pp.1-14
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    • 2002
  • The purpose of this study was to develop the expert system based on the artificial neural networks for architectural design phases. The applied building was secondary school focussed in its space-relational-diagram. To implement this system, a data matrix derived from case based database was used as learning pattern, and its output data was lastly evaluated by the educational phase's behavior & activity analysis data. The results of this study were as follows; 1) the needs of educational system for real world spacing can be solved by this expert system based on neural networks. 2) FCM also can be applied for architect's needs. 3) Afterwards, for developing architectural planning & design processes, information technology (for example, internet, odbms, dca and etc.) can be used.

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Parameter Measurement and Dynamic Performance Estimation of Synchronous Reluctance Motor Considering Iron Loss (철손을 고려한 자기저항 동기전동기의 정수 측정 및 동특성 예측)

  • Lee, J.S.;Hong, J.P.;Hahn, S.C.;Joo, S.W.
    • Proceedings of the KIEE Conference
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    • 1999.07a
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    • pp.58-60
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    • 1999
  • This paper presents dynamic performance prediction using Matlab / simulink after parameter estimation of synchronous reluctance motor considering iron loss. Test motor is 3 phase SynRM with the segmental rotor, rating power is 0.175KW. Experiment equipment is consists of testing motor, dynamometer, vector invertor dynamocontroller, and power analyser. The stator iron loss and rotor iron loss are modelled by additional windings on three-phase winding axis. These windings are transformed into d-q axis, and are represented as equivalent eddy current windings. P-Q circle diagram method and single phase standstill method are used to measure motor parameters considering iron loss.

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Partial Miscibility of Polymer Solutions in the Theory of Flory's Equation of State With Specific Interaction (특정상호작용을 갖는 Flory 상태방정식 이론에서의 고분자 용액의 부분혼합도)

  • Hae Young Jung
    • Journal of the Korean Chemical Society
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    • v.36 no.6
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    • pp.941-946
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    • 1992
  • Partial miscibilities of polymer solutions are investigated when the specific interactions between different molecules are added to the theory of Flory's equation of state. Especially, it is shown that the closed loop phase diagram can appear. The general conditions for the partial miscibility are derived and the general effects of several factors to that are investigated.

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A System Dynamics Approach to shift the paradigm to be highly educated person (고학력 지향 패러다임의 전환을 위한 시스템 다이내믹스적 접근)

  • Kim, Do-Hoon;Hong, Young-Kyo
    • Korean System Dynamics Review
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    • v.11 no.4
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    • pp.97-115
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    • 2010
  • 'JOBLESS GROWTH' is a word to explain the world's common problem of unemployment. But, 'highly educated youth unemployment' is the unique condition that Korea society is facing. In this paper, we determine the cause of the problem with causal loop diagram and reach the conclusion. It is the paradigm to be highly educated person and that paradigm became permanent after the Korean War. People think that only highly educated person can bring wealth and honor, so they spend much money for their children's private education to enter university. Though young people receive bachelor's degree, they spend much money to get job. To solve these problems, this paper suggest three solutions. The first is to shift the paradigm to be highly educated person. The second is to expand the opportunities of public education as education system of Finland. And the third is to support the youth aptitude.

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Dynamic Analysis of FCEV Turbo Blower (연료전지 자동차용 터보 블로워의 동특성 해석)

  • Yook, J.Y.;Yang, H.S.;Lee, C.H.;Cho, K.S.;Kim, K.I.;Kwon, H.R.;Park, Y.S.
    • Transactions of the Korean Society for Noise and Vibration Engineering
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    • v.21 no.7
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    • pp.591-598
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    • 2011
  • This paper presents dynamic analysis of FCEV(fuel cell electric vehicle) turbo blower. To analyze the dynamic characteristics of turbo blower, FEA(finite element analysis) and experimental test are performed. Evaluations of stress safety for rotor sleeve and impeller due to rotational force and shrink fit are performed. Rotor dynamic analysis is conducted by Campbell diagram and structure vibration analyses are performed using FEA and experimental test. Through these results, noise sources of turbo blower are verified.

Structural stability of laminated composite material for the effectiveness of half axial wave mode: Frequency impact

  • Muzamal, Hussain
    • Advances in concrete construction
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    • v.14 no.5
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    • pp.309-315
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    • 2022
  • This paper depicts the diagram of cylindrical shells as an essential idea. It centers around an outline of exploration and use of cylindrical shell in expansive current circumstance. In view of investigation of the current and prospect of model as a piece of present exploration work, a straightforward contextual analysis is examined with Love's shell theory based on Galerkin's method. The cylindrical shells are attached from one end of the cylindrical shells. The frequencies of ring support shells are investigated against the half axial wave mode. The frequencies increase on increasing the half axial wave mode. Also, the frequencies are downsized with ring supports. The software MATLAB is preferred to others because in this software computing coding is very easy to do. Just single command 'eig' furnishes shell frequencies and mode shapes by calculating eigenvalues and eigenvectors respectively. The shell vibration frequencies for cylindrical shells are compared with those results found in the open literature.

The Relationship of Froude Number and Developed Cloud Band Locations Near Yeongdong Region Under the Siberian High Pressure System (시베리아 고기압 영향으로 영동지역 부근에서 발달한 구름대의 위치와 Froude 수와의 관계)

  • Kim, Yu-Jin;Kim, Man-Ki;Lee, Jae Gyoo
    • Atmosphere
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    • v.29 no.3
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    • pp.325-342
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    • 2019
  • Precipitation and no-precipitation events under the influence of the Siberian high pressure system in Yeondong region, were analysed and classified as four types [obvious precipitation event (OP) type, obvious no-precipitation event (ON) type, ambiguous precipitation event (AP) type and ambiguous no-precipitation event (AN) type], according to the easiness in determining whether to have precipitation or not in Yeongdong region, to help in improving the forecast skill. Concerning the synoptic pressure pattern, for OP type, the ridge of Siberian high extends from Lake Baikal toward Northeast China, and there is a northerly wind upstream of the northern mountain complex (located near the Korean-Chinese border). On the other hand, for ON type, the ridge of Siberian high extends southeastward from Lake Baikal, and there is a westerly wind upstream of the northern mountain complex. The pressure pattern of AP type was similar to the OP type and that of AN type was also similar to ON type. Thus it was difficult to differentiate AP type and OP type and AN type and ON type based on the synoptic pressure pattern only. The four types were determined by U (wind speed normal to the Taebaek mountains) and Froude number (FN). That is, for OP type, average FN and U at Yeongdong coast are ~2.0 and ${\sim}6m\;s^{-1}$, and those at Yeongseo region are 0.0 and $0.1m\;s^{-1}$, respectively. On the contrary, for ON type, average FN and U at Yeongdong coast are 0.0 and $0.2m\;s^{-1}$, and those at Yeongseo region are ~1.0 and ${\sim}4m\;s^{-1}$, respectively. For AP type, average FN and U at Yeongdong coast are ~1.0 and ${\sim}4m\;s^{-1}$, and those at Yeongseo region are 0.0 and $0.2m\;s^{-1}$, whereas for AN type, average FN and U at Yeongdong coast are 0.1 and $0.6m\;s^{-1}$ and those at Yeongseo region are ~1.0 and ${\sim}3m\;s^{-1}$, respectively. Based on the result, a schematic diagram for each type was suggested.

The New Korea Innovation Systems: An Application of System Dynamics Approach (새로운 과학기술혁신체제의 시스템다이내믹스)

  • Won, Dong-Kyu;Yun, Jin-Hyo
    • Korean System Dynamics Review
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    • v.6 no.1
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    • pp.71-98
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    • 2005
  • If Korea Research & Development reinforces integrated control function, indeed would Korea Research & Development's output be increased? Truly, could Korea's competition be ultimately improved with technology innovation and accumulation of knowledge. Can reinforcement of Integrated control that reinforced efficiency of Research & Development's investment effects make Korea Research & Development's investment,itself, be decreased? I try to answer clearly that in a way to reorganize Korea technology Administration's system, introduced Korea Research & Development integrated control system's establishment is what to effect Korea innovation system's direction after answering clearly previous mentioned problems. In this study, to answer these problems view theoretical discussion about Korea innovation system, integrated control system and system dynamics. Set up analytic tools of system dynamics which includes Korea innovation system and integrated control system. Then, draw a general casual loop diagram, which includes established Korea Research & Development's integrated control system, of Korea innovation system's activity. In based these, develop situation model to analyze trend of Korea innovation system and derive a political meaning by analyzing value of Korea innovation system's major inflow, outflow and stock variations according to extent of Korea Research & Development's integrated control in the same model.

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