• 제목/요약/키워드: Break-In

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창업 중소.벤처기업의 초기자금 규모 설정에 관한 연구 (A Study on the Early-Stage Financing Scale for Building Small & Medium Business)

  • 황보윤
    • 한국벤처창업학회:학술대회논문집
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    • 한국벤처창업학회 2006년도 추계학술발표회
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    • pp.275-299
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    • 2006
  • This study aims at examining the early-stage financing scale for entrepreneur to build small & medium business. The data was collected from the DART (Data Analysis, Retrieval and Transfer System) of Korean Financial Supervisory Service(FSS) in the main. The results of this study show that small & medium business needs equipment & operation financing for about 37 months extent to reach Break-Even Point. The limitations of this study are data collections from registered firms on Korean FSS primarily and no showing about the early stage financing scale for building small & Medium Business concretely. Small & Medium business entrepreneur have to make a early stage finance plan according to a necessary equipment and operating cost in their business field for 37 months extent.

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2유체 정전분무의 액체 미립화 및 분무 특성 (Liquid Atomization and Spray Characteristics in Electrostatic Spray of Twin Fluids)

  • 김정헌;배충식
    • 대한기계학회논문집B
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    • 제25권11호
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    • pp.1552-1560
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    • 2001
  • This paper presents the experimental results of a study undertaken to develop an electrostatic spray system for a combustion application. The characteristics of the liquid atomization and the droplet dispersion in the electrostatic spray of twin fluids were investigated by the optical measurement techniques. The processes associated with the break-up of charged jets were also observed using the laser sheet visualization. The diameter and velocity of droplets were simultaneously measured using the phase Doppler measurement technique. The electrostatic atomization of the liquid fuel depended primarily on the charging voltage and the flow rate, but the dispersion of droplets depended significantly on the aerodynamic flow. Aerodynamic influences on the liquid atomization decreased with an increase of the charging voltage. Consequently, the liquid atomization and the droplet dispersion could be independently controlled using the electrostatic and aerodynamic mechanisms.

표면크랙의 관통 및 파단 피로수명의 확률분포 (Probabilistic Distribution of Penetration and Break Fatigue Life of Surface Crack)

  • 윤한용
    • 대한기계학회논문집
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    • 제18권10호
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    • pp.2495-2500
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    • 1994
  • A method of prediction for the fatigue life of surface crack, that is, initial cracks grow and penetrate through the thickness, was presented in the previous study of the author. Effects of parameters such as the initial crack length, material factors, etc., for the life were discussed. In this paper, the probabilistic distribution of the life is calculated. Effects of the distribution of parameters for the distribution of life were also discussed.

전류 차단기 메커니즘에서 에너지방법을 이용한 차단 속도에 따른 스프링 모델링 (Opening Spring Modeling of Current Circuit Breaker Mechanism with respect to Opening Speed using Energy Method)

  • 권병희
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2000년도 추계학술대회논문집A
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    • pp.688-692
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    • 2000
  • This study proposed design parameters of opening spring of circuit breaker that cut off the over-current in order to protect the electric device about opening speed using the energy method. We simulated the opening kinetic energy, the potential energy of opening spring and the design parameters of opening spring with respect to opening speed of VCB (Vacuum Circuit Breaker)'s moving contactor which has 24kV 25kA break capacity. From the result of simulation the initial tensional force and the final tensional force of the opening spring chose 107kgf and 282kgf respectively. Through the dynamic analysis using ADAMS, We verified that the opening speed of moving contactor satisfied break capacity of VCB and analyzed opening dynamic characteristics of VCB such as the opening displacement, the opening velocity and the opening acceleration of moving contactor in time domain.

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노즐 형상에 따른 디젤 연료 분무의 발달 예측에 관한 수치 해석적 연구 (The Numerical Study on Prediction of Diesel Fuel Spray Evolution in a Different Types of Nozzle Geometry)

  • 민세훈;서현규
    • 한국분무공학회지
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    • 제22권4호
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    • pp.169-174
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    • 2017
  • The objective of this study was to verify the experimental and numerical results of spray evolution injected from different types of the nozzle-hole geometries. Spray visualization was taken by high speed camera under the different conditions. For the simulations of spray tip penetration, turbulence, evaporation and break-up model were applied K-zeta-f, Dukowicz and Wave model, respectively. Also, the prediction accuracy of spray tip penetration was increased by varying the spray cone angle. At the same time, the results of this work were compared in terms of spray tip penetration, and SMD characteristics. The numerical results of spray evolution process and spray tip penetration showed good agreement with experimental one.

An Analysis of a Post-Trip Return-to-Power Steam Line break Events

  • Baek, Seung-Su;Lee, Cheol-Sin;Song, Jin-Ho;Lee, Sang-Yong
    • 한국원자력학회:학술대회논문집
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    • 한국원자력학회 1995년도 추계학술발표회논문집(2)
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    • pp.544-549
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    • 1995
  • An analysis for Steam Line Break (SLB) events which result in a return-to-power conditions after reactor trip was performed for a postulated Yonggwang Nuclear Power Plant Unit 3 cycle 8. Analysis methodology for post-trip return-to-power SLB is quite different from that of a no return-to-power SLB and is more complicated. Therefore, it is necessary to develop an methodology to analyze the response of the NSSS parameter and the fuel performance for the post-trip return-to-power SLB events. In this analysis, the cases with and without offsite power were simulated by crediting 3-D reactivity feedback effect due to local heatup around stuck CEA and compared with the cases without 3-D reactivity feedback with respect to fuel performance, departure from nucleate boiling ratio (DNBR) and linear heat generation rate (LHGR).

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중소기계제조업의 사업포지셔닝에 영향을 미치는 생산관련 핵심성과지표에 관한 연구 (A study on the analysis of production-related key performance indicator affecting business positioning of machinery manufacturers)

  • 정해석;유우식
    • 대한안전경영과학회지
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    • 제14권2호
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    • pp.221-228
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    • 2012
  • This paper analyzed twenty-six production-related KPI(Key Performance indicator) factors of business diagnosis, such as personnel, equipment, materials, operations and quality affecting company business competition to 186 small machinery manufacturers in 2010. Also, we explained the concept of Business Positioning and divided research subjects into four Business Positioning Groups formed break-even point ratio & fixed cost ratio to sales and then we compared between the 4 groups using Logistic Regression analysis by SAS statistical software package. The objective of this study is two-fold. The first is to find out production-related KPI factor of superior Business Positioning Group. The second is to suggest improvement ways for small manufacturers in order to get better profitable Business Positioning.

유한체적법에 의한 자유수면 유동해석에서 Level-Set 기법에 대한 연구 (A Study on the Level-Set Scheme for the Analysis of the Free Surface Flow by a Finite Volume Method)

  • 박일룡;전호환
    • 대한조선학회논문집
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    • 제36권2호
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    • pp.40-49
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    • 1999
  • 이류체(two fluids)의 경계면인 자유수면 유동해석을 위해서 2차원 비압축성, 이류체 Navier-Stokes방정식을 유한체적법(Finite Volume Method)으로 이산화 하고 level-set기법을 적용하였다. Level-set기법의 수치적 특성과 문제에 대한 적용성을 간략히 살펴보고 평가하기 위하여 수조 내에서 주기적으로 진동하는 미소 표면파와 댐붕괴(dam break)문제에 적용하였다. 수치계산 결과에서는 해의 수렴성을 개선하기 위한 방법을 소개하였다.

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가압열충격을 고려한 원자로 압력용기의 파괴역학적 해석 (Fracture Mechanics Analysis of a Reactor Pressure Vessel Considering Pressurized Thermal Shock)

  • 박재학;박상윤
    • 한국안전학회지
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    • 제16권4호
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    • pp.29-38
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    • 2001
  • The purpose of this paper is to evaluate the structural integrity of a reactor pressure vessel subjected to the pressurized thermal shock(PTS) during the transient events, such as main steam line break(MSLB) and small break loss of coolant accident(SBLOCA). For postulated surface or subsurface cracks, variation curves of stress intensity factor are obtained by using the three different methods, including ASME section XI code anlysis, the finite element alternating method and the finite element method. From the stress intensity factor curves, the maximum allowable nil-ductility transition temperatures(RT/NDT/) are determined by the tangent criterion and the maximum criterion for various crack configurations and two initial transient events. As a result of the analysis, it is noted that axial cracks have smaller maximum allowable RT$_{NDT}$ values than same-sized circumferential cracks for both the transient events in the case of the tangent criterion. Axial cracks have smaller RT$_{NDT}$ values than same-sized circumferential cracks for MSLB and circumferential cracks have smaller values than axial cracks for SBLOCA in the case of the maximum criterion.

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화물자동차운송업의 최저경영규모산정에 관한 연구 (A Study on the Minimum Scale of Business for Transportation Enterprises)

  • 이삼재;강경식
    • 대한안전경영과학회지
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    • 제9권5호
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    • pp.111-116
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    • 2007
  • The objective of this paper is to calculate the minimum scale of management for transportation business in order to achieve a form of enterprise. In this study the tracking minimum scale of business is the minimum number of operating trucks. Transportation companies should ensure the number of trucks for a type of business model rather than a means of livelihood model. The method to calculate the minimum number of trucks for the transportation business model can use an approach of either the qualitative and the quantitative technique. This study chooses the quantitative technique to calculate the minimum number of trucks through the analysis of break-even point.