• 제목/요약/키워드: cycle-based evaluation

검색결과 568건 처리시간 0.03초

공기식 태양열 흡수기의 설계 및 성능평가 (Design and Performance Evaluation of Solar Air Receivers)

  • 조현석;이현진;김종규;이상남;강용혁
    • 한국태양에너지학회:학술대회논문집
    • /
    • 한국태양에너지학회 2012년도 춘계학술발표대회 논문집
    • /
    • pp.280-285
    • /
    • 2012
  • It is important to produce the high temperature and high pressure air for the concentrated solar power system using the combined cycle. In this paper, based on the concept of tubular receiver, we designed two types with focus on radiation loss reduction. These two receivers were tested in the KIER solar furnace of 40kW thermal capacity. Performance of the two receivers were evaluated and compared.

  • PDF

L5/S1에 걸리는 부하염력과 척추기립근 근전도의 상관관계 분석 (Relationship Between Compressive Force at L5/S1 and Erector Spinae Muscle Electromyography)

  • 장성록
    • 한국안전학회지
    • /
    • 제10권4호
    • /
    • pp.103-108
    • /
    • 1995
  • This study was performed to investigate a relationship between a biomechanical analysis of compressive force at L5/S1 and electromyographic analysis of erector spinae muscle during lifting task. In the experiment, isometric contractions at 25, 50, 75, 100%MVC for short duration and sustained isometric contractions at 50%MVC were performed. For muscle recruitment patten and compressive force analysis, rectified EMG amplitudes analysis and computerized biomechanical analysis were used. To achieve data, angles of neck, shoulder, elbow, wrist, hip, knee, ankle and length of body segments were measured. Results shows that trends of initial EMG rectified amplitude were similar to those of biomechanical calculation value and for sustained isometric contraction at 50%MVC EMG rectified amplitude of erector spinae muscle after 40seconds was increased up to level of 75%MVC. Based on the results of this study, biomechanical analysis should be supplemented considering muscle fatigue, and it is also suggested that work-rest cycle critera and the evaluation of back-pain injuries should include muscle fatigue.

  • PDF

LPG 액정분사식 대형 버스용 엔진 피스톤의 피로수명 해석과 냉각조건 평가 (Fatigue Life Analysis and Cooling Conditions Evaluation of a Piston for Large LPLi Bus Engines)

  • 최경호;이부윤
    • Journal of Advanced Marine Engineering and Technology
    • /
    • 제28권5호
    • /
    • pp.762-772
    • /
    • 2004
  • Fatigue life of a Piston for large liquid Petroleum liquid injection(LPLi) bus engines is analyzed considering effects of cooling condition parameters : temperature of cooling water, and heat transfer coefficients at oil gallery and bottom surface of piston head. Temperature of the piston is analyzed with varying cooling conditions Stresses of the piston from two load cases of pressure loading. and pressure and thermal loading are analyzed Fatigue life under repeated peak pressure and thermal cycle is analyzed by the strain-life theory. For the two load cases, required loading cycles for engine life are defined, and loading cycles to failure and partial damages are calculated. Based on the resulting accumulated fatigue usage factors, endurance of the piston is evaluated and effects of varying cooling condition Parameters are discussed.

Software Quality Metrics를 이용한 공학용 전산 프로그램의 품질특성 측정 (Quality Evaluation of Engineering Computer Programs Using Software Quality Metrics)

  • 조문성;남지희
    • 품질경영학회지
    • /
    • 제25권4호
    • /
    • pp.115-130
    • /
    • 1997
  • SQM (Software Quality Metrics) is a methodology whose primary objective is the measurement of compliances to requirements using a set of software life cycle properties called quality factors, which is based on the hierachical relationshiips between factors, criteria and elements. For this study, two factors (Correctness, Maintainability) and five criteria were selected. In addition, several tens of quality elements were developed to su, pp.rt them. Qualities of three computer programs which are being used for engineering purpose were measured. As a result, it is concluded that SQM is a valuable method for continuously monitoring the pulse of software quality development and that it can be used as a tool for software quality assurance.

  • PDF

CAE 기법을 이용한 서스펜션 너클의 피로수명 평가 (Fatigue Life Prediction of Suspension Knuckle by CAE Technology)

  • 김영진;서명원;서상민;서재호;김중재
    • 한국자동차공학회논문집
    • /
    • 제3권2호
    • /
    • pp.112-121
    • /
    • 1995
  • Various CAE technologies are used in automobile industries for the purpose of design and analysis. In this paper, a fatigue life evaluation system FLEVA based on the local strain approach is developed and the system is applied for the fatigue strength design of the suspension knuckle, an automobile component. Various steps such as material test, finite element analysis and cumulative fatigue damage analysis of the suspension knuckle were taken. The usefulness of the approach was verified by the fatigue test on the suspension knuckle.

  • PDF

주문 변화를 반영하는 스케줄링 규칙에 대한 시뮬레이션을 이용한 성능 평가 (Performance Evaluation of Scheduling Rules Considering Order Change Using Simulation)

  • 박종관;이영훈
    • 한국시뮬레이션학회논문지
    • /
    • 제9권3호
    • /
    • pp.13-26
    • /
    • 2000
  • The scheduling rule for the fabrication process of the semiconductor manufacturing is suggested and tested on the simulation system which was developed based on the model to represent the main characteristics of wafer flows. The proper scheduling policies are necessary to meet the order change in the supply chain management. It was shown that the suggested rules which consider the wafer balance and the due date of the order, give good performances for the cycle time reduction and the rate of meeting due date as well. Also they are robust in the sense that performances are stable regardless of the order change rate and the input policies.

  • PDF

중합효소연쇄반응 기기의 온도 사이클링 제어시스템 설계 (Thermal Cycling Control System Design for Polymerase Chain Reaction(PCR) Machine)

  • 김종해;조용석;오도창
    • 제어로봇시스템학회논문지
    • /
    • 제12권5호
    • /
    • pp.419-424
    • /
    • 2006
  • In this study, a thermal control system which applied a Peltier device for the polymerase chain reaction(PCR) machine is to be designed. Here in order for it to easily follow the characteristics of the thermal cycle existing for gene amplification of the PCR sample, a PCR control board utilizing a thermal sensor, a Peltier, and a 8 bit microprocessor is made up. Especially a fuzzy type PD control algorithm is applied periodically in time response, and control system is implemented. For that matter, the characteristic data of subject system is obtained and analysed to begin with. Based on this analysed data, the proposed control algorithm is applied and an evaluation of the performance of the whole system take place through the PC.

피로강도 변동성을 고려한 Pulley의 내구성 평가 (Evaluation of Pulley Durability Considering the Variation of the Fatigue Strength)

  • 심희진;김철수;오원철;김정규
    • 대한기계학회:학술대회논문집
    • /
    • 대한기계학회 2004년도 춘계학술대회
    • /
    • pp.394-399
    • /
    • 2004
  • In order to secure the safety of power steering system, it is necessary to perform the strength and the fatigue analysis of pulley in this paper. The applied stress distribution of the pulley subject to combined loads condition was obtained using finite element analysis. Based on these results, the fatigue life of the pulley with the variation of the fatigue strength was evaluated using durability analysis simulator. The optimal hole size to improved the safety of the pulley was investigated using parametric study. Moreover, the predicted fatigue life cycle with the simulator was verified by experimental tests.

  • PDF

Virtual Disassembly

  • Mo, Jianzhong;Zhang, Qiong;Gadh, Rajit
    • International Journal of CAD/CAM
    • /
    • 제2권1호
    • /
    • pp.29-37
    • /
    • 2002
  • De-manufacturing is an entire process of collecting, disassembling, reusing, refurbishing, recycling, and/or disposing products that are obsolete or un-repairable. Designing the products for inexpensive and efficient disassembly enhances the ease of de-manufacturing. Virtual disassembly addresses the difficulty and the methods to disassemble a product in design stage rather than really disassemble a product at the end of its life cycle. Based on the virtual disassembly analysis results, design will be improved for better assembling/disassembling. This paper presents a systematic virtual disassembly methodology such as disassembly relation modeling, path/sequence automatic generation and evaluation. This paper also presents a new virtual disassembly interface paradigm via virtual reality technology for disassembly simulation in virtual environment.

금강유역의 습윤/건조 상태에 대한 경향성 분석 (Trend Analysis of Wetness/Dryness in Geum River Basin)

  • 김주철;이상진;황만하;안정민
    • 한국수자원학회:학술대회논문집
    • /
    • 한국수자원학회 2010년도 학술발표회
    • /
    • pp.1640-1644
    • /
    • 2010
  • In this study the wetness/dryness in Geum river basin are classified by dint of cumulative probability density function of monthly moisture index and the long term changes of them are analyzed based on climatic water balance concept. The drought events in Geum river basin are selected through evaluation of monthly moisture index and the various hydrological properties of them are investigated in detail. Also the trends of time-series of climatic water balance components are examined by Seasonal Kendall test and the variability of hydrological cycle in Geum river basin during the recent decade is inquired. It is judged that the results of this study can be contributed to establishment of the counter plan against the future drought events as the fundamental information.

  • PDF