• 제목/요약/키워드: Performance degree

검색결과 3,644건 처리시간 0.032초

Comparison of Unconfined and Confined Micro-scale Impinging Jets

  • Choo, Kyo-Sung;Youn, Young-Jik;Kim, Sung-Jin
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2008년도 추계학술대회B
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    • pp.2210-2213
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    • 2008
  • In the present study, effects of degree of confinement on heat transfer characteristics of a micro-scale slot jet impinging on a heated flat plate are experimentally investigated. The effects of Reynolds numbers (Re = $1000{\sim}5000$), lateral distances (x/B = $1{\sim}10$), nozzle-to-plate spacings (Z/B = $1{\sim}20$), and degree of confinement ($B_c$/B = 3, 48) on the Nusselt number are considered. The results show that the effects of the degree of confinement on the cooling performance of the micro-scale impinging slot jet are significant at lower nozzle-to-plate spacings and higher Reynolds numbers. In addition, it is shown that the cooling performance of the micro-scale unconfined slot impinging jet is 200% higher than that of the micro-scale confined slot impinging jet.

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모(시.천정)와의 동거여부와 취업주부의 생활만족도에 미치는 영향 (A Study about Living together or not with the Mothers (Mothers-in-law/Mothers) and the Life Satisfaction of employed Wives)

  • 하경란
    • 가정과삶의질연구
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    • 제15권4호
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    • pp.301-314
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    • 1997
  • The purpose of this study is to analyze difference of life satisfaction of employed wives by living with mother-in-law or mothers. Life satisfaction of employed wives are measured by marital satisfaction the satisfaction of used time and role performamce and financial satisfaction. For this study 449 employed wives in Tajean are the subjects of survey. The main results were as follows; 1. The degree of life satisfaction of employed wives indicated more than middle level(M=3.44) While the degree of satisfaction in marital satisfaction indicated high the degree of satsifaction in the used time and role performance indicated low 2. On the whole the influential valiables on the marital satisfacton of employed wives were found in the following oreders; wife's and husband's educationa level job and income. 3. There were a non-significant difference in the life satisfaction of employed wives between living with mothers or not. But the differences between living with mothers-in-low an mothers were significant in the satisfaction of used time and role performance.

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2-자유도 중첩센서의 최적배치 (Optimal configurations for redundant two-degree of freedom sensor systems)

  • 정도형;이장규;박찬국;박흥원;정태호
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1991년도 한국자동제어학술회의논문집(국내학술편); KOEX, Seoul; 22-24 Oct. 1991
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    • pp.258-263
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    • 1991
  • Optimal configurations for redundant TDOF (Two Degree Of Freedom) sensor systems are proposed. The determinant of error covariance matrix is used as the performance index, and optimal configurations for 2 TDOF sensor system and 3 TDOF sensor system are evaluated by minimizing the index.

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대학도서관 정보사서의 정보서비스 효율성 평가 (An Evaluation for Effectiveness of Information Services by Reference Librarians at College and University Libraries in Korea)

  • 한상완
    • 한국문헌정보학회지
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    • 제13권
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    • pp.95-119
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    • 1986
  • The objective of this study is to search for a theoretical and practical solution to the question of what is the most effective and qualitative method of information service for the college and university libraries in Korea. Assuming the maximum service or total service theory in information services, therefore, it appears natural that the subject specialist who is highly knowledgeable in his subject is indispensable in raising the quality of information librarians. The procedure of this research was as follows: There was no college and university library employing any full-time subject spceialist in Korea. This research, however, was proceeded on the assumption that subject specialists are already employed in all of the college and university libraries after the subject specialist system is established. The least qualification of subject specialist is limited, based on the criteria given by the foreign literature, to those who have master's degree in Library Science and bachelor's degree in any other subject area, those who have bacholor's degree in Library Science and master's degree in any other subject area, or those who have both bacholor's and master's degrees in Library Science with minor in any subject field . To prove the research hypothesis that the subject specialist will perform his role more efficiently than the generalist in effectively providing information service based on both accuracy and speed, this research as an obtrusive testing method analyzed the effectiveness by presenting information questions to the generalists and subject specialists who are information librarians in college and university libraries. For this study 20 librarians working at 12 university libraries were tested for performance levels of information services. The result showed $59.75\%$ an absolute performance rate and $75.20\%$ an adjust performance rate. Compared to Thomas Childer's 1970 study in which he used the unobtrusive testing method, these results were $5\%$ higher in the absolute performance rate and $11.36\%$ higher in the adjust performance rate. In comparing the generalist with the subject specialist in efficiency of information service, while the absolute performance rate was $57.08\%$ and the adjust performance rate was $73.08\%$ in the case of the generalist, the absolute rate was $63.75\%$ and the adjust rate was $78.38\%$ in the case of specialist, therefore, the efficiency of the subject specialist was $6.67\%$ higher in the absolute performance rate and $5.30\%$ higher in the adjust performance rate than that of generalist. But the factor of speediness was excluded from the analysis because of the difference between the time the interviewers recorded and the time the interviewee recorded. On the basis of the result of this research, it should be desirable to educate subject specialists and employ them as information librarians and for them to function as efficient subject specialists in order to improve the effectiveness of information services, the nucleus of the raison d'etre of college and university libraries.

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입원아동 보호자의 간호요구와 보호자가 지각한 간호사의 간호수행 정도 (Nursing Needs and Nursing Performance as Perceived by Caregivers with Hospitalized Children)

  • 정은;권인수
    • Child Health Nursing Research
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    • 제21권3호
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    • pp.244-252
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    • 2015
  • Purpose: The purpose of this study was to identify differences between the degree of nursing need and nursing performance as perceived by caregivers of hospitalized children. Methods: Participants included 200 main caregivers from two pediatric hospitals where their children had been hospitalized for at least 2 days. Data were collected from October 30 to December 10, 2014. Results: The degree ($2.64{\pm}0.40$) of nursing performance perceived by caregivers with hospitalized children was found to be significantly lower than that ($3.39{\pm}0.21$) of nursing needs of caregivers. Of nursing needs, direct nursing had the highest score at 3.59, and nursing assessment, the lowest at 3.23. For nursing performance, nursing assessment had the highest score at 2.76, and education and counseling, the lowest at 2.35. Conclusion: These results suggest that performance of nursing activities by nurses caring for hospitalized children do not meet the nursing needs of the caregivers. Therefore it is necessary to develop nursing strategies to reduce the gap between nursing needs and nursing performance.

치위생 임상실습에 대한 실습기간별 관찰/수행실습의 정도와 만족도 분석 (A Study on length of Clinical Practice Observation/Performance of Dental and Hygiene the Degree of Satisfaction)

  • 노미경
    • 한국치위생학회지
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    • 제5권2호
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    • pp.185-199
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    • 2005
  • The purpose of this research is to suggest a new desirable direction to a positive educational program for dental hygeine students, through the analysis of the degrees of observation and performance practice and the student satisfaction. This researched 471 senior dental hygien students from 5 separate universities. SPSS 10.0 for Windows was used to transform the results data analysis into statistics. The students' degree of satisfaction and length of observational/performance practice level were measured. For statistical anlysis the Mean and Standard Deviation were computed and the t-test and ANNOVA were carried out. The significant level of these statistics was a=0.05. 1. 12 weeks practice is the highest in the satisfaction of observation practice was the highest in clinical settings, followed by 16 weeks practice, and 8 weeks practice. 2. 12 weeks practice is the highest in the satisfaction of performance practice, followed by 16 weeks practice, and 8 weeks practice. 3. 8 weeks practice is the highest in the satisfaction of performance practice, followed by 12 weeks practice, and 16 weeks practice. 4. According to the frequency of clinical practice and satisfaction 12 week program of observation/performance practice is the most desirable, followed by 16 weeks practice, and 8 weeks practice.

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임펄스성 잡음이 존재하는 실내 무선 환경에서 Multi-Carrier CDMA 시스템의 성능 분석 (Performance Analysis of Multi-Carrier CDMA Systems under Indoor Wireless Environment with Impulsive Noise)

  • 이영춘;박기식;조성준
    • 한국항행학회논문지
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    • 제7권1호
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    • pp.30-37
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    • 2003
  • 본 논문에서는 Middleton이 제안한 A급 임펄스성 잡음이 존재하는 실내 무선 환경에서 MC (Multi-Carrier) CDMA 시스템의 BER (Bit Error Rate) 성능을 분석하였고, 임펄스성이 약한 환경에서부터 강한 환경까지 성능을 평가하였다. 그리고 임펄스성 잡음에 대한 보상 방법으로 Turbo 부호기를 사용하여 성능 개선 정도를 평가하였다. 성능 해석 결과, 임펄스성 잡음 환경에서는 강력한 성능 개선 기법이 시스템에 반드시 필요함을 알 수 있었다. 그리고 임펄스성 잡음 환경에서 터보 부호를 적용하면 BER면에서 약 $10^{-2}$정도 개선됨을 알 수 있었고, AWGN 환경에 근접할수록 터보 부호에 의한 성능 개선 효과가 뚜렷이 나타남을 알 수 있었다.

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Research on bearing characteristics of socket-spigot template supporting system

  • Guo, Yan;Hu, Chang-Ming;Lian, Ming
    • Steel and Composite Structures
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    • 제20권4호
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    • pp.869-887
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    • 2016
  • The socket-spigot template supporting system is widely used in engineering applications in China. As a newer type of support structure, there has been growing research interest in its bearing capacity. In this paper, four vertical bearing capacity tests were carried out on the basic mechanical unit frame of a socket-spigot template supporting system. The first goal was to explore the influence of the node semi-rigid degree and the longitudinal spacing of the upright tube on the vertical bearing capacity. The second objective was to analyze the displacement trend and the failure mode during the loading process. This paper presents numerical analysis of the vertical bearing capacity of the unit frames using the finite element software ANSYS. It revealed the relationship between the node semi-rigid degree and the vertical bearing capacity, that the two-linear reinforcement model of elastic-plastic material can be used to analyze the socket-spigot template supporting system, and, through node entity model analysis, that the load transfer direction greatly influences the node bearing area. Finally, this paper indicates the results of on-site application performance experiments, shows that the supporting system has adequate bearing capacity and stability, and comments on the common work performance of a socket and fastener scaffold.

격판분리 축열조의 히트펌프 성능개선 효과 (Effect of heat pump performance improvement by use of thermal tank with temperature seperation plate)

  • 문종필;이성현;권진경;강연구;이수장
    • 한국신재생에너지학회:학술대회논문집
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    • 한국신재생에너지학회 2011년도 춘계학술대회 초록집
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    • pp.80.1-80.1
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    • 2011
  • This study was carried out in order to estimate the effect of heat pump performance by use of thermal tank with 3 seperation plates which were able to divide thermal tank into 3 chambers that have different temperatures levels. For testing the effect of developed thermal tank which was installed for supplying the heat to the paprika greenhouse in Jinju city. The volume of thermal storage tank was designed for $110m^3$ which was able to cover 30% of heating capacity. The temperature difference was 3 degree Celcius between high temperature and low temperature when only heating circulation was made from heat pump to thermal tank. but 5.5 degree Celcius difference was made when heating circulation of heat pump to thermal thank and hot water supplying circulation of thermal tank to greenhouse was done simultaneously. As a result of this study showed that COP of heat pump was increased by 15% or more than that of using normal thermal tank because heat pump was able to take 3 ~ 5 degree Celcius lower thermal thank water constantly.

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컨셉 변동 스트리밍 데이터를 위한 적응적 가중치 조정을 이용한 동적 앙상블 방법 (A Dynamic Ensemble Method using Adaptive Weight Adjustment for Concept Drifting Streaming Data)

  • 김영덕;박정희
    • 정보과학회 논문지
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    • 제44권8호
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    • pp.842-853
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    • 2017
  • 스트리밍 데이터는 시간에 따라 지속적으로 생성되는 데이터 시퀀스이다. 시간이 지남에 따라 데이터의 분포 또는 컨셉이 변화할 수 있으며, 이러한 변화는 분류 모델의 성능을 저하시키는 요인이 된다. 점층적 적응적 학습 방법은 컨셉 변화의 정도에 따라 현재 분류 모델의 가중치를 조절하여 업데이트를 수행함으로써 컨셉 변화에 대한 분류 모델의 성능을 유지할 수 있게 한다. 그러나, 컨셉 변화의 정도에 맞는 적절한 가중치를 결정하기가 어렵다는 문제점이 있다. 본 논문에서는 컨셉 변화에 따른 적응적 가중치 조정에 기반한 동적 앙상블 방법을 제안한다. 실험 결과는 제안한 방법이 다른 비교 방법들에 비해 높은 성능을 보여줌을 입증한다.