• 제목/요약/키워드: Effectiveness

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이중분사 막냉각 홀의 측면 분사각 및 홀 사이의 거리가 막냉각 효율에 미치는 영향 (Effects of the Lateral Ejection Angles and Distances of Double-Jet Holes on Flim Cooling Effectiveness)

  • 최대웅;이기돈;김광용
    • 한국유체기계학회 논문집
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    • 제15권4호
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    • pp.33-41
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    • 2012
  • In the present work, a parametric study on double-jet film-cooling has been carried out to enhance the film-cooling effectiveness using three-dimensional Reynolds-averaged Navier-Stokes analysis. The shear stress transport turbulence model is used as the turbulence closure. The lateral ejection angles and the lateral and streamwise distance between the centers of the cooling holes are chosen as the geometric parameters. The spatially averaged film-cooling effectiveness averaged over an area of 8 hole diameters in width and 30 hole diameters in streamwise length is used to evaluate the performance of film-cooling. The parameter of the lateral distance has the largest impact on the film cooling effectiveness compared to the others. On the other hand, the parameter of streamwise distance gives the least influence on the film cooling effectiveness.

Electrochemical Effectiveness Factors for Butler-Volmer Reaction Kinetics in Active Electrode Layers of Solid Oxide Fuel Cells

  • Nam, Jin Hyun
    • Journal of Electrochemical Science and Technology
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    • 제8권4호
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    • pp.344-355
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    • 2017
  • In this study, a numerical approach is adopted to investigate the effectiveness factors for distributed electrochemical reactions in thin active reaction layers of solid oxide fuel cells (SOFCs), taking into account the Butler-Volmer reaction kinetics. The mathematical equations for the electrochemical reaction and charge conduction process were formulated by assuming that the active reaction layer has a small thickness, homogeneous microstructure, and high effective electronic conductivity. The effectiveness factor is defined as the ratio of the actual reaction rate (or equivalently, current generation rate) in the active reaction layer to the nominal reaction rate. From extensive numerical calculations, the effectiveness factors were obtained for various charge transfer coefficients of 0.3-0.8. These effectiveness data were then fitted to simple correlation equations, and the resulting correlation coefficients are presented along with estimated magnitude of error.

국공립과 사립 유치원교사의 조직효과성에 대한 사회인구학적 변인 및 임파워먼트의 영향 비교 (A Comparison of the Influence of Demographic Variables and Teacher's Empowerment on Organizational Effectiveness in Public and Private Kindergartens)

  • 김정희;문혁준
    • 아동학회지
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    • 제31권2호
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    • pp.69-83
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    • 2010
  • This study was a comparative investigation of the influence of demographic variables and teacher's empowerment on organizational effectiveness in public and private kindergartens. The subjects were 303 teachers at either public or private kindergartens. The measures used for this study were questionnaires, the SPES(School Participant Empowerment Scale) and the Organizational Effectiveness Scale. The survey used in this study and data were analyzed by means of a t-test, Pearson's correlation, and multiple regression analyses. The results showed that teachers in public kindergartens had higher scores in terms of both empowerment and organizational effectiveness than teachers in private kindergartens. Empowerment was seen to be an influential factor in measuring teacher's organizational effectiveness.

임상실습지도자의 효율성 조사와 임상평가도구 개발 (A Survey of Teaching Effectiveness and the Development of an Evaluation Instrument for Clinical Education)

  • 권미지
    • The Journal of Korean Physical Therapy
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    • 제14권1호
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    • pp.177-186
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    • 2002
  • The purpose of this study was to contribute to the development of clinical instruction by students ratings of teaching effectiveness in clinical education. The instrument used in this study was teaching effectiveness of clinical nursing by Yu and modified evaluation method by Kern and Mickelson. The results were are follows 1. Among the 12 categorial components of clinical teaching effectiveness, the highest satisfaction was 'encouraging to think for themselves' and the lowest was 'attitude of teacher and evaluation' 2. To compare teaching effectiveness between sex, 'resource for student' and 'professional competence' showed statistical significance. 3. To compare teaching effectiveness among clinical practice stage, 'encouraging' 'role model', 'professional competence', 'organization of subject mater' and 'attitude of teacher and evaluation' showed statistical significance. 5. Interrater ICCs for evaluation method did not showed statistical significance and interitem ICCs showed statistical significance. This article presents goal of clinical education, development of clinical instructor's educational program and a standardized method to measure clinical performance.

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병원간호사의 학습조직화와 학습지향성이 조직유효성에 미치는 영향 (The Effect of Learning Organization Construction and Learning Orientation on Organizational Effectiveness among Hospital Nurses)

  • 강경화;송기준
    • 간호행정학회지
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    • 제16권3호
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    • pp.267-275
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    • 2010
  • Purpose: This study conducted to identify the effect of learning organization construction and learning orientation on organizational effectiveness among hospital nurses. Method: Data was collected from convenient sample of 296 nurses who worked for the major hospitals in Seoul, Gyeonggi-do and Gangwoen-do. The self-reported questionnaire was used to assess the general characteristics, the level of the learning organization construction, learning orientation and organizational effectiveness. The data were analyzed using descriptive statistics, pearson's correlation coefficient and multiple regression. Result: The mean score of learning organization construction was 3.61(${\pm}.32$), learning orientation got 3.26(${\pm}.39$), and organizational effectiveness obtained 3.38(${\pm}.42$). The learning organization construction affects of organizational effectiveness by 44.18% and learning orientation by 37.43%. Conclusion: This finding indicates that learning organization construction and learning orientation affects the nurses' organizational effectiveness in hospital.

Bayesian Statistical Modeling of System Energy Saving Effectiveness for MAC Protocols of Wireless Sensor Networks: The Case of Non-Informative Prior Knowledge

  • Kim, Myong-Hee;Park, Man-Gon
    • 한국멀티미디어학회논문지
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    • 제13권6호
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    • pp.890-900
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    • 2010
  • The Bayesian networks methods provide an efficient tool for performing information fusion and decision making under conditions of uncertainty. This paper proposes Bayes estimators for the system effectiveness in energy saving of the wireless sensor networks by use of the Bayesian method under the non-informative prior knowledge about means of active and sleep times based on time frames of sensor nodes in a wireless sensor network. And then, we conduct a case study on some Bayesian estimation models for the system energy saving effectiveness of a wireless sensor network, and evaluate and compare the performance of proposed Bayesian estimates of the system effectiveness in energy saving of the wireless sensor network. In the case study, we have recognized that the proposed Bayesian system energy saving effectiveness estimators are excellent to adapt in evaluation of energy efficiency using non-informative prior knowledge from previous experience with robustness according to given values of parameters.

ISO 9000/14000 인증효과에 대한 실증적 연구 (An Empirical Study on the Effectiveness of ISO 9000/14000-Registered Companies in Korea)

  • 이군희
    • 품질경영학회지
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    • 제34권2호
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    • pp.98-106
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    • 2006
  • ISO 9000/14000 certification is increasingly becoming 'a passport for business' in the marketplace. However, its effectiveness of both internal and external performance is highly controversial. In this study, empirical research is performed to identify the main objectives and expectation of ISO 9000/14000 and evaluate the effectiveness of certification. Our empirical results show that there are big differences between small and medium companies and large companies for the effectiveness of ISO 9000/14000. Especially, ISO 14000 certification provides very low effectiveness for the small and medium companies in Korea.

C-G Method를 이용한 지그재그 노면표시의 교통사고 감소효과 분석 (Estimation of Traffic Accident Effectiveness of Zig-zag Marking Using a Comparison Group Method)

  • 권성근;이영인;조성준
    • 한국도로학회논문집
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    • 제14권6호
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    • pp.149-158
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    • 2012
  • PURPOSES : This research is to evaluate the effects of zig-zag marking. METHODS : Based on the literature review, This research adopt Comparison Group method which was developed by Hauer. RESULTS : The findings are as follows. Effectiveness of treatment at all site 1.06, intersection 0.92, median bus lane 1.93, school zone 0.50, below 6-lane 0.48, above 6-lane 1.19, cat vs person 0.57, car vs car 1.36, car only 1.29. CONCLUSIONS : Though the analysis, it was founded that zig-zag marking on the small scale road(below 6-lane) and school zone contribute to reduce traffic accidents(effectiveness of the treatment : 0.50, 0.48). But the accidents at large scale road and median bus lane where installed zig-zag marking demonstrated negative result.(effectiveness of the treatment indicates exceed 1.0).

육군 훈련교육에서 시뮬레이터 시스템의 지각된 교육효과에 관한 연구 (A Study on Percepted Education Effectiveness of Simulator System in the Army Training Education)

  • 이영재;김호진
    • 한국정보처리학회논문지
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    • 제7권5호
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    • pp.1456-1463
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    • 2000
  • The main objective of this study is to show how to measure the education effectiveness of simulator system in the army. We investigate the education effectiveness through the measuring model that consists of three dimensions such as understanding, experience, and learning. The results of empirical analysis demonstrate that the education effectiveness depends on three dimensions. The result also suggests that the higher the degree of each dimension is, the higher the education effectiveness. However, there is no education effectiveness difference between the traditional training and the simulator training because of the elementary level of simulator function.

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육군 방공자동화체계 전투효과 분석에 관한 연구 (A Study on the Analysis of Combat Effectiveness of the Army C2A System)

  • 최우찬;이재영
    • 한국국방경영분석학회지
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    • 제30권2호
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    • pp.63-80
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    • 2004
  • This paper develops a methodology which can be used to quantify the combat effectiveness of the army C2A system by modifying C2 theory and using Air Defense Engagement Simulation. In this paper, by using Schutzer's C2 theory and Measures of Effectiveness, we modified the MOE formula he designed. Because the combat effectiveness by enhancement of C2(Command and Control) system will increase combat power of individual asset independently. In addition, we developed simulation analysis of air defense scenario by using Air Defense Engagement Simulation. The results show that modified the MOE formula is proper as compared with Air Defense Engagement Simulation method. The combat effectiveness can be obtained as a result of improved probability of detection and information accuracy through real-time information sharing and coordination by C2A system.