• 제목/요약/키워드: The present

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세계의 원자력선

  • 정운혁
    • Nuclear Engineering and Technology
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    • 제7권1호
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    • pp.53-68
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    • 1975
  • The world's nuclear powered ships have been reviewed mainly based on development of the marine nuclear reactor and the present trends of nuclear warships and merchant ships in the world. In particular, emphasis was on the four nonmilitary nuclear ships, Russian Ice breaker Lenin, American Cargo-passenger ship Savannah, German Ore carrier Otto Hahn, and Japanese Cargo ship Mutsu. They are the only civilian nuclear ships which have entered service at the present time in the world. The nuclear fleets in United States, United Kingdom, Soviet, and France were described in view of historical development and the present stock of the nuclear ships. The present projects and the future trends for the nuclear merchant ships in the main shipbuilding countries have been also discussed. The nuclear fission and reactor were briefly discussed in the beginning of this article.

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New emerging viral infections in human beings that first appeared in Asia: a summary for the present decade 2001 - 2010

  • Wiwanitkit, Viroj
    • 셀메드
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    • 제1권1호
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    • pp.3.1-3.4
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    • 2011
  • Emerging infectious diseases are usually a public concern. The presence of new emerging infectious diseases is a topic to be reported on and discussed about in medicine. Several new emerging infectious diseases have occurred within the present decade. In this specific review, the author briefly reviews the important new emerging human viral infections that first appeared in Asia during the present decade, 2001 - 2010.

기회비용 개념을 이용한 실물투자 프로젝트의 전략적 순 현재가치의 구성요소와 경제적 해석 (Investigation of the Structure of the Strategic Net Present Value and Its Economic Interpretation through the Opportunity Cost Concept)

  • 김규태;최성호
    • 대한산업공학회지
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    • 제29권2호
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    • pp.126-134
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    • 2003
  • Among a variety of models proposed by so far to calculate the real options value when the investment decision about the underlying project may be delayed, the Black-Scholes and the binomial lattice models have been widely used and discussed by academics and practitioners. However these two models do not provide us with intuition into how it is constructed and what it does really mean. In this paper, we will therefore explore its components and practically more intuitive meaning. With the components explored, we developed the mathematical model to calculate the real options value and thus strategic net present value, based on the opportunity cost concept, for which the investment decision about the underlying project is postponed by one year. We will finally present a short illustrative example for readers better understanding on the model proposed in the paper.

의류산업에서의 패션전문직종 현황에 관한 연구 (A Study on the Present Situation of Fashion Careers in the Apparel Industry)

  • 이인자
    • 복식
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    • 제30권
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    • pp.41-58
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    • 1996
  • To purpose of this study is to understand the present situation of the present situation of the fashion careers in apparel industry and to present a activation information for development of a specialty de-partment. This study has been proceeded with the library survey method, and 20 apparel enterprises have been researched with the questionaire and inter-view method. These were large and medium sized enterprises. The results were as follows: 1. Subdivision of fashion careers have been found insufficient on apparel enterprises in Korea. 2. Textile specialists have been needed on apparel enterprises in Korea. 3. Domestic enterprises have dropt out man-agement 4. These enterprises are negative for the consumer research and fashion information col-lection. 5. Fashion sepecialists have been found insuf-ficient on retail division, The propositions for activation of fashion careers are as follows: 1. Fashion careers should subdivide and specialize. 2. The apparel enterprises should employ textile designer. 3. The apparel enterprises should activate practical department. 4. The apparel enterprises should research consumer and collect fashion information. 5. The apparel enterprises should develop fashion specialists on retail division.

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유동한계 고상율법을 이용한 수축공 생성의 수치해석 (Numerical Analysis of Shrinkage Cavity Formation using the Modified Fluid Critical Solid Fraction Method)

  • 이재경;최정길;홍준표
    • 한국주조공학회지
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    • 제18권6호
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    • pp.555-562
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    • 1998
  • Modified fluid critical solid fraction method was utilized as a prediction parameter to describe the shrinkage formation including the position, shape and amount of shrinkage cavities. A numerical scheme was implemented adapting this method for the evaluation of solidification defects in various casting processes. In the present numerical code, the form of shrinkage cavity can be simultaneously determined when an isolated loop is predicted to occur by the fluid critical solid fraction method. An auxiliary parameter, shrinkage potential, was also used in order to calculate the amount of residual liquid during solidification. Solidification analysis was carried out for the validation of the present scheme. It was shown that the calculated results were in good agreement with those of practical casting runs in all of the casting processes envolved in the present research. It may be concluded that the present program successfully predicts the detailed shrinkage formation behavior without the consideration of interdendritic fluid flow analysis.

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음향방출 특성을 이용한 콘크리트 부재종류 및 하중상태에 따른 균열손상 연구 (Identification of Damage Characteristics for the Cracking of Concrete Strcuture Using Acoustic Emission)

  • 오병환;권일범;김응재;김광수
    • 한국콘크리트학회:학술대회논문집
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    • 한국콘크리트학회 1999년도 봄 학술발표회 논문집(I)
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    • pp.543-546
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    • 1999
  • The purpose of the present study is to identify the damage characteristics of concrete structures due to cracking by employing the acoustic emission techniques. A comprehensive experimental study has been done. The cracking damages under tensile and flexural loadings have been identified and the bond damage between steel and concrete have been also characterized. It is seen that the amplitudes and energy level of AE events is found to be smaller for bond cracking damages and larger for tensile cracking damages. The characteristic equations of the AE events for various cracking damages have been proposed based on the present test data. The internal microcracks are progressively developed ahead of a visible actual crack and the present study clearly exhibits thses damage mechanism for various types of cracking in concrete. The present study provides very useful data which can be used to identify the various types of cracking damages in concrete structures. This will allow very efficient maintenance of concrete structures through monitoring of internal cracking based on acoustic emission.

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시내외 전화서비스 가격의 최적결정에 관한 실증연구

  • 지경용
    • ETRI Journal
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    • 제10권4호
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    • pp.146-160
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    • 1988
  • The purpose of the present study is to build a model to determine the structure of long-term quasi-optimal rates of local and toll telephone services. The outline of this study is as follows : Telephone business, providing social goods, is capital-intensive industry which needs huge fixed cost to operate exchanges and telephone networks nationwide. The nature of above industry justifies the market structure of telephone business to be natural monopoly and makes a good reason for government's direct regulation, that is, price regulation. Three is a gap between the present rates and the quasi-optimal ones because some administrative processes intervene in rate making process before execution. On the above diagnostic basis, the present study made an empirical test for the optimality of present rates structure in connection with Ramsey-Boiteux model to maximize the sum of producer's and consumer's surplus and also the current study proposed a qusasi-optimal rates structure for better market performance. From the empirical analysis, we can deduce a policy recommendation the local price should be increased to 47% whereas toll price decreased to 24% in order to improve the net welfare worth of 32.6 billion won.

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학교급식 조리사의 직무분석 (The Job Analysis of Cooks of School Foodservice)

  • 한경수;채영철;김숙희;표은영
    • Journal of Nutrition and Health
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    • 제35권10호
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    • pp.1104-1119
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    • 2002
  • This study was to analyze the job of cooks of school foodservice. The purpose of this study were to examine importance of the present job and future-oriented job of cooks in school foodservice, and to compare the present job performance time with the future-oriented job performance time. The questionnaire was delveloped by focus group and pilot test. The work sampling was choosed to verify the objectivity of job analysis. The statistical software package was SAS 10.0. ‘Menu Management’, ‘Procurement’, ‘Receiving and Inventory control’ and ‘Cooking facilities Management’ of the present job was perceived significantly more important than the future-oriented job. ‘Procurement’, ‘Receiving and inventory control’, ‘distribution’ and ‘dishwashing’ of the future-oriented job was perceived significantly longer than the present job performance time. This study will be used to develop job specification for the cooks of school foodservice.

Filtering Technique to Control Member Size in Topology Design Optimization

  • Kim, Tae-Soo;Kim, Jae-Eun;Jeong, Je-Hyun;Kim, Yoon-Young
    • Journal of Mechanical Science and Technology
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    • 제18권2호
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    • pp.253-261
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    • 2004
  • A simple and effective filtering method to control the member size of an optimized structure is proposed for topology optimization. In the present approach, the original objective sensitivities are replaced with their relative values evaluated within a filtering area. By adjusting the size of the filtering area, the member size of an optimized structure or the level of its topological complexity can be controlled even within a given finite element mesh. In contrast to the checkerboard-free filter, the present filter focuses on high-frequency components of the sensitivities. Since the present filtering method does not add a penalty term to the objective function nor require additional constraints, it is not only efficient but also simple to implement. Mean compliance minimization and eigenfrequency maximization problems are considered to verify the effectiveness of the present approach.

복강경 수술용 도구의 실시간 영상 추적 및 복강경 조종기의 지능형 제어 방법 (Real-time Visual Tracking System and Control Method for Laparoscope Manipulator)

  • 김민석;허진석;이정주
    • 한국정밀공학회지
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    • 제21권11호
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    • pp.83-90
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    • 2004
  • In this paper we present a new real-time visual servoing unit for laparoscopic surgery This unit can automatically control laparoscope manipulator through visual tracking of laparoscopic surgical tool. For the tracking, we present two-stage adaptive CONDENSATION(conditional density propagation) algorithm to extract the accurate position of the surgical tool tip from a surgical image sequence in real-time. This algorithm can be adaptable to abrupt change of laparoscope illumination. For the control, we present virtual damper system to control a laparoscope manipulator safely and stably. This system causes the laparoscope to move under constraint of the virtual dampers which are linked to the four sides of image. The visual servoing unit operates the manipulator in real-time with locating the surgical tool in the center of image. The experimental results show that the proposed visual tracking algorithm is highly robust and the controlled manipulator can present stable view with safe.