• 제목/요약/키워드: therefore

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시스템 안전 분석기법 활용방안에 대한 연구 (The Application Method of System Safety Analysis Technique)

  • 김병석
    • 대한안전경영과학회:학술대회논문집
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    • 대한안전경영과학회 1999년도 추계학술대회
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    • pp.355-363
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    • 1999
  • Free from the industrial accident is the goal from top manager to foreman. Therefore all the company try to prevent occupational accident using system safety program in order to increase productivity Korean industries have been tend to depending upon historical information to control risk. The other hand, foreign industries have been Identify risk factors using system safety techniques to predict future risk. Therefore, this study is presented to applying the foreign industries's risk control technique to korean industries.

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3상 다이오드 정류기의 Simulink 모델 (Simulink Model of 3-Phase Diode Rectifiers)

  • 이진우
    • 전력전자학회:학술대회논문집
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    • 전력전자학회 2001년도 전력전자학술대회 논문집
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    • pp.514-519
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    • 2001
  • Most of inverters adopt a diode rectifier as an input stage, which has very simple and rugged structure and therefore low cost. In order to properly design the 3-phase diode rectifier with an output smoothing capacitor and input inductors, it is necessary to fully simulate the system due to its nonlinear characteristics. Therefore this paper describes the operating behaviors including the current commutation in detail by using the proposed equivalent circuit, and also proposes the Simulink-based model of the system. The simulation results show the validity of the proposed model in all operating conditions.

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4 단자망을 이용한 고장해석 (Fault Analysis, Using Two-Port Network)

  • 김주용;백영식
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1993년도 하계학술대회 논문집 A
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    • pp.124-127
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    • 1993
  • This paper presents the new algorithm for fault analysis and the fault analysis package for executing this algorithm. This algorithm obtains requisite term for fault analysis by the two-port network technique. Therefore, the fault calculation time is minimized because ${Y_{BUS}}^{-1}$ calculation time is removed. And, the graphic user environment for fault analysis is implemented in mouse-oriented user interface with window and pull-down menu. Therefore, this package can be a useful tool for fault analysis.

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태풍으로 인한 시간강수량의 변동성 분석 (Analysis of Hourly Precipitation Change by Typhoon)

  • 문영일;오태석;신동준
    • 한국방재학회:학술대회논문집
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    • 한국방재학회 2008년도 정기총회 및 학술발표대회
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    • pp.497-500
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    • 2008
  • The typhoon is provoking huge damage attacking in Korea periodically every year. Therefore, in this study, the analysis of 24 hourly maximum precipitation change related to typhoon events achieved based on Mann-Whitney U test, T test, Modified T test, Sign test, F test, and Modified F test. At the results, the 24 hourly maximum precipitation was expose that average and standard deviation are increasing recently. Therefore, hydorlogical structures have to be prepared of extreme rainfall events by typhoons.

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해고와 주주의 부와의 관계 연구 (A study on the relationship between layoff and shareholders' wealth)

  • 이재범
    • 대한안전경영과학회지
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    • 제3권4호
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    • pp.113-122
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    • 2001
  • This study is to examine the effect of layoff on shareholders' wealth. Firms make layoff decisions by reason of cost cutting, lower performance, demand decline, restructuring. Therefore, I think that stock market responds to layoff positively, since the firm's labor productivity and profitability is improved after execution of layoff, I find that layoff variables effect on abnormal return positively in regression analysis. This means that layoff sends positive signal to the stock market for the firm's future performance. Therefore, layoff has a good effect on shareholders' wealth.

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한국과 미국의 실내디자인학 대학원 현황과 학위제도 특성 (Interior Design Graduate Education System and Degrees in Korea and the U.S.)

  • 심은주
    • 한국실내디자인학회논문집
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    • 제23권6호
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    • pp.133-141
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    • 2014
  • Graduate education in general means nurturing scholars who are capable of research that adds to the 'body of knowledge' and educators in the higher education system. Therefore 'discovering' new knowledge has always been a major role of graduate schools. However, interior design is a special field that 'application' can also produce new knowledge and therefore a wider understanding of scholarship is needed especially in the graduate level education. The purpose of this paper is to understand Interior Design graduate education system in the United States in order to develop issues that need to be discusses and addressed in Korea. Therefore, this paper first examines meanings of graduate degrees in general and current situation of Interior degrees offered in Korea. Then investigates the different types of graduate degrees in the U.S. such as post-professional degrees, first-professional degrees, and differences in general degree(M.A., M.S.) and professional degrees (M.F.A., M.I.D.). The researcher has used websites of each school and information lists of degrees offered by KIID and IDEC that serves as the main educators council in each countries. The characteristics of graduate degrees in America can be described as a structured system based on variety, flexibility, and distinction. For instance, M.F.A means a professional degree that is focused on building theory based project abilities, longer period to study but counted as a terminal in the field. However, in Korea even though the title of the degrees may differ there is not much difference shown in the educational contents. Therefore issues such as developing a more universal and international degree system, flexible and selective educational road-map, mutual understanding and unified system between various organizations for better graduate education system are proposed. Moreover, hope to start a discourse on defining scholarship and professionalism in the field of Interior Design.

칼라 등색선무늬용 광탄성실험 하이브릿법 개발에 관한연구 (A Study on the Development of Photoelastic Experimental Hybrid Method for Color Isochromatics)

  • 권오성;황재석;남정환;한송령;권건;류의
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2007년도 춘계학술대회A
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    • pp.66-71
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    • 2007
  • Isochromatics obtained from photoelastic experiment shows the stress distributions of full field of a structure under a load. Therefore stress distributions of the structure can be read at a glace through isochromatics. Many experimental data are obtained from isochromatics. And then, the various photoelastic experimental hybrid methods have been developed. Until now, monochromatic light has been used for photoelastic experimental hybrid method. Therefore the photoelastic experimental hybrid method used until now is called the photoelastic experimental hybrid method for black and white isochromatics. When stresses are analyed by photoelastic experimental hybrid method, many experimental data are needed. Therefore some fringe orders of isochromatics are needed for the photoelastic experimental hybrid method for white and black isochromatics. Therefore in this paper, the photoelastic experimental hybrid method for color isochromatics is developed. In this case, two fringe orders are enough for the experimental data of photoelastic experimental hybrid method for color isochromatics. Applying the method to stress concentration problems, its validity is confirmed. In the precision, the photoelastic experimental hybrid method for color isochromatics is better than the photoelastic experimental hybrid method for white and black isochromatics when fringe orders of isochromatics are few. When fringe orders are few, the photoelastic experimental hybrid method for color isochromatics can be used to analyze stress through few fringe orders of isochromatics.

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태풍 접근에 의한 바람 환경 변화가 건물에 미치는 영향 (Effects of Changing in Wind Environment of Typhoon Approaching to a Building)

  • 박종길;정우식;최효진
    • 한국신재생에너지학회:학술대회논문집
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    • 한국신재생에너지학회 2009년도 춘계학술대회 논문집
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    • pp.561-564
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    • 2009
  • In order to reduce damage from natural disasters, prevention activities through analysis and predicting based on meteorological factor and damage data is required. Other countries already have continuously studied on natural disasters and developed reducing disasters damage. But the risk assessment model for natural disaster is not to Korea. Therefore, a previous model of hurricane, Florida Public Hurricane Loss Model(FPHLM), is the basis and is applying to domestic situation. Accordingly, this study introduces the variables selecting process because input variables should be selected under Korea present state and be used. The estimating representative damage method would be necessary along with selecting housing types representing relevant areas because estimating damage amount of all over relevant areas housing was very hard during damage estimating process. But there is no exact representative housing types in the Korea. Therefore, we select housing types applicable to risk assessment model for natural disasters representing the Korea through previous studies and literature reviews. We using ASCE 7-98(Minimum Design Loads for Buildings and Other Structures, 1998) standard which estimated wind load using 3-second gust. ASCE 7-98 divided Main Wind Force Resistance System(MWFRS) and Component and Cladding(C&C) and it estimated wind load. Therefore, we estimate wind load affected by 3-second gust of a typhoon Maemi through calculating wind load process using selected representative detached house types in the process of selecting input variables for previous disaster predict model. The result of houses damage amount is about 230 hundred million won. This values are limit the 1-story detached dwelling, 19~29pyeong(62.81~95.56 $m^2$) of total area and flat roof. Therefore, this process is possible application to other type houses.

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Traditional Chinese Medicine and its Application for Fashion Design

  • Kim, Hye-Eun
    • International Journal of Costume and Fashion
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    • 제9권2호
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    • pp.35-48
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    • 2009
  • Therapeutic garments are an undeveloped area and yet they have the potential to generate considerable profit for the fashion industry. In traditional Chinese medicine, there are spots and pathways on the body through which energy flows and practitioners consider that disease results when this energy flow is hindered. Clothes which stimulate the spots can therefore potentially help to cure disease. In addition, clothes are worn every day and can therefore offer prolonged treatment certainly in comparison with other treatments. Obesity is a big problem nowadays and one which is caused by poor energy circulation (according to TCM). A garment which stimulates the spots can assist energy flow and therefore cause the wearer to lose weight. In the process, it can also alleviate side effects of obesity such as diabetes and high blood pressure. The was to stimulate spots include acupuncture, acupressure, moxibustion etc. There are lots of products to press spots which improve energy flow both in the Western and Chinese markets. The basic principle of circulation is in fact the same in both Western and Chinese medicine. However, most of these are products are footwear ones because they can easily provide the necessary stimulation to reduce tiredness and improve circulation. For garments, to press the spots effectively it is best to use tight clothes such as corsets and leggings. The important point is to tighten the body and to make energy flow and yet feel comfortable at the same time. Choice of fabric is therefore an important issue. Although the idea has been introduced, it will be necessary to develop a technique which will allow the necessary amount of pressure to be applied. It could be concluded that this area has a lot of possibility for the future but further research will need to be done before the idea becomes workable.

Feasibility Confirmation of Angular Velocity Stall Control for Small-Scaled Wind Turbine System by Phase Plane Method

  • Asharif, Faramarz;Shiro, Tamaki;Teppei, Hirata;Nagado, Tsutomu;Nagata, Tomokazu
    • IEIE Transactions on Smart Processing and Computing
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    • 제2권4호
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    • pp.240-247
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    • 2013
  • The main aim of this study was to suppress the angular velocity against strong winds during storms and analyze the stability and performance of the phase plane method. The utilization of small-scale wind turbine system has become common in agriculture, houses, etc. Therefore, it is considered to be a scheme for preserving the natural energy or avoiding the use of fossil fuels. Moreover, settling small-scaled wind turbines is simpler and more acceptable compared to ordinary huge wind turbines. In addition, after converting the energy there is no requirement for distribution. Therefore, a much lower cost can be expected for small-scaled wind turbines. On the other hand, this system cannot be operated continuously because the small-scaled wind turbine consists of a small blade that has low inertia momentum. Therefore, it may exceed the boundary of angular velocity, which may cause a fault in the system due to the centrifugal force. The aim of this study was to reduce the angular velocity by controlling the stall factor. Stall factor control consists of two control methods. One is a shock absorber that is loaded in the junction of the axis of the blade of the wind turbine gear wheel and the other is pitch angle control. Basically, the stall factor itself exhibits nonlinear behavior. Therefore, this paper confirmed the feasibility of stall factor control in producing desirable performance whilst maintaining stability.

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