• 제목/요약/키워드: systematic factor

검색결과 965건 처리시간 0.029초

발포알루미늄 다공핀의 열유동특성 (Flow and Heat Transfer Characteristics of Aluminum Foam Porous Fins)

  • 김서영;백진욱;강병하
    • 설비공학논문집
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    • 제12권5호
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    • pp.511-518
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    • 2000
  • The present experimental study investigates the impact of porous fins on the pressure drop and heat transfer characteristics in plate-fin heat exchangers. Systematic experiments have been carried out in a simplified model of a plate-porous fin heat exchanger at a controlled test environment. Comparison of performance between the porous fins and the conventional louvered fins has been made. The experimental results indicate that friction and heat transfer rate are significantly affected by permeability as well as porosity of the porous fin. The porous fins used in the present study show a similar air-side performance to the louvered fin. The correlations of friction and modified j-factor are also given for the design of the plate-porous fin heat exchanger.

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병원에 근무하는 간병인의 업무적 특성과 직무스트레스가 근골격계 자각증상에 미치는 요인 (The Related Factor of Job Characteristics and Occupational Stress on Musculoskeletal Symptom for Caregiver Working in Hospital)

  • 최율정;심현보
    • 대한정형도수물리치료학회지
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    • 제18권1호
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    • pp.19-29
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    • 2012
  • Background: This study was conducted to investigate subjective musculoskeletal symptom and the related factor of caregiver. Methods: For 300 caregiver, we used the self-administered questionnaires to examine occupational stress and subjective musculoskeletal symptom designed by KOSHA. The collected data were analyzed chi-square test, independent t-test and multiple logistic regression analysis using SPSS 12.0. Results: The multiple logistic regression analysis showed that the caregiver working in the general hospital significantly increased the subjective musculoskeletal symptom in their neck, shoulder, hand/wrist/finger, back, leg/foot. For the caregiver working in hospital showed significantly increased the subjective musculoskeletal symptom in their hand/wrist/finger and leg/foot. Conclusions: With the above results, continuous and systematic prevention program should be established, which include the ergonomics and psychosocial factor for the caregiver's musculoskeletal symptom.

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퍼지 PI scaling factor의 분석적인 유도방법에 관한 연구 (A Study on an Analytical Approach to the Derivation of Fuzzy PI Scaling Factor)

  • 전기영
    • 전력전자학회:학술대회논문집
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    • 전력전자학회 2000년도 전력전자학술대회 논문집
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    • pp.460-463
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    • 2000
  • Fuzzy logic control(FLC) has been studied extensively and has been applied in various applications. The most popular control strategy takes the Fuzzy Proportional-Integral(FPI) form while systematic methods have been developed to derive the fuzzy rules and membership functions the choice of the scaling factors remains an open problem, In this paper an analytical FPI scaling factor determining method is derived based on the functional equivalence of the PI and FPI controllers. Simulation have been carried out with a brushless DC motor drive system as test-bed the obtained results drive system as test-bed the obtained results have verified that the derived method is applicable to both the initial choice and further tuning of the FPI scaling factors.

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사무소용빌딩의 전력소비특성을 고려한 특징파라메터 및 회귀분석을 통한 조명 및 일반동력부하의 수용률 분석 (Recommended Practice for Demand Factor by Feature Parameters and Regression Analysis depending on Power Consumption Characteristics in Office Buildings)

  • 김세동;남기범;정형용;신화영;김성환
    • 한국조명전기설비학회:학술대회논문집
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    • 한국조명전기설비학회 2005년도 춘계학술대회논문집
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    • pp.331-336
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    • 2005
  • It is increased electrical energy consumption with the development of intelligence society in the office buildings and thus an energy conservation through efficient use of electricity became more important. This paper shows a reasonable design demand factor in office buildings, that was made by the systematic and statistical way considering actual conditions, such as investigated electric equipment capacity, peak power consumption, demand factor, etc., for 54 office buildings and 34 electrical design offices. In this dissertation, it is necessary to analyse the key features and general trend from the investigated data. It made an analysis of the feature parameters, such as average, standard deviation, median, maximum, minimun and thus it was carried linear and nonlinear regression analysis.

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Comparison and Study of Active and Hybrid Power Filters for Compensation of Grid Harmonics

  • Gutierrez, Bryan;Kwak, Sang-Shin
    • Journal of Power Electronics
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    • 제16권4호
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    • pp.1541-1550
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    • 2016
  • This paper presents a theoretical analysis and comparisons of active power filter (APF) and hybrid power filter (HPF) systems, given terminal constraints of harmonic compensations in nonlinear loads. Despite numerous publications for the two types of filters, the features and differences between them have not been clearly explained. This paper presents a detailed analysis of the operations of a HPF inverter along with those of passive power filters (PPFs). It also includes their effects on the power factor at the grid. In addition, a theoretical analysis and a systematic comparison between the APF and HPF systems are addressed based on system parameters such as the source voltage, output power, reactive component size, and power factor at the grid terminals. The converter kVA ratings and dc-link voltage requirements for both topologies are considered in the presented comparisons

여중생의 하반신 의복설계를 위한 체형분류 및 특성 (Characteristics and Classification of the Lower Body Somatotype for the Construction of Junior High School Girls' Clothing)

  • 김혜경;임지영
    • 대한가정학회지
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    • 제37권1호
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    • pp.109-118
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    • 1999
  • The effective construction for ready-made clothes is one of the central concerns of both consumers and manufactures in today's apparel industry. So in order to reduce the burden of stocks and increase clothing fitness, systematic information on typical body size and somatotypes is essential. This study was performed to provide fundamental data on junior high school girls' somatotype by classifying the lower body somatotype and analyzing the characteristics of each somatotype. The subject were 234 Korean Junior High School Girls. The subjects were directly measured anthropometrically and indirectly analyzed photographically. The result of factor analysis indicated that 6 factors were extracted through factor analysis and those factors comprise 70.2% of total variance. Using factor scores cluster analysis was carried out and the subject were classified into 3 cluster as their lower boby front and side silhouette.

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다변량분석법에 의한 측면전신체형 분류 (Classification and Analysis of the Somatotype through Side View Silhouette of the whole body by Multivariate Method)

  • 권숙희
    • 한국의류학회지
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    • 제21권7호
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    • pp.1227-1235
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    • 1997
  • The purpose of this study was to classify the somatotype based on the side view and to analyze the characteristics of each somatotype. In order to reduce the burden of stocks and increase clothing fitness, systematic information on typical body sizes and somatotypes is essential. The subjects were 206 unmarried women aged from 19-29. Data were collected through anthropometry and photometry and analyzed by factor analysis, cluster analysis and analysis of variance. As the result of factor analysis for the classification of somatotypes, 8 factors which explain 74.7% of variance were extracted from 35 photometric and 17 anthrometric data. Using factor scores cluster analysis was carried out and the subjects were classified into 4 cluster.Each cluster was classified as bending type, swayback, turning over type and straight type accordding to its position to the relativeplumb line and their side view contour.

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종합병원의 전력소비 특성을 고려한 회귀분석이론을 이용한 수용률 기준 설정 (Recommended Practice for Demand Factor using Regression Analysis Theory depending on Power Consumption Characteristics in General Hospitals)

  • 김세동;신효섭;김수길;오기봉
    • 한국조명전기설비학회:학술대회논문집
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    • 한국조명전기설비학회 2005년도 학술대회 논문집
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    • pp.233-237
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    • 2005
  • It is increased electrical energy consumption with the development of intelligence society in the general hospitals and thus an energy conservation through efficient use of electricity became more important. This paper shows a reasonable design demand factor in office buildings, that was made by the systematic and statistical way considering actual conditions, such as investigated electric equipment capacity, peak power consumption, demand factor, etc., for 32 general hospitals and 9 electrical design offices. In this dissertation, it is necessary to analyse the key features and general trend from the investigated data. It made an analysis of the feature parameters, such as average, standard deviation, median, maximum, minimun and thus it was carried linear and nonlinear regression analysis.

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영양교사의 자질 및 업무에 대한 인식도 분석 (The Perception of Nutrition Teacher's Competency and Duty)

  • 이해영;이은주
    • 대한지역사회영양학회지
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    • 제14권3호
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    • pp.316-326
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    • 2009
  • The purposes of this study were to identify the significance of a nutrition teacher, to analyze the importance of competence as a nutrition teacher and to evaluate the importance and difficulty for duties of nutrition teachers. The questionnaire was distributed to 554 preliminary teachers and a total of 468 usable data were collected with 84.5% of response rate from August to October 2006. The statistical data analysis was completed by using SPSS Win (ver. 10.0) for descriptive analysis, t-test, ANOVA and ${\chi}^2-test$. The results were as follows: Preliminary nutrition teachers expected that conversion of a school dietitian into a nutrition teacher could lead to systematic and constant nutrition education and come into synergic effect by doing meal service with nutrition education. For a teacher's competence, all three paradigms were perceived as important. It was evaluated to be high for a knowledge factor in the empirical analytic paradigm, a personality factor in the practical interpretive paradigm and an attitude factor in the critical emancipatory paradigm. And 'a knowledge for nutrition and sanitation (4.59)' and 'an ability to raise a self-management capacity for right food habit and dietary life (4.59)' were showed as most important in a nutrition teacher. It appeared that both important and difficult duties of nutrition teachers were nutrition education, nutrition counseling and sanitation quality of nutrition education; the most necessary solution was to develop a reference and program for nutrition education (37.4%). In conclusion, the systematic supports of district offices of education and associated institutions as well as sustained efforts of preliminary nutrition teachers for themselves should lead to establish a successful system of nutrition teachers.

A Systematic Process of Product Design Based on Customer Preferences

  • Chun Young H.;Baek Ingie;Jung Eui S.
    • 한국품질경영학회:학술대회논문집
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    • 한국품질경영학회 1998년도 The 12th Asia Quality Management Symposium* Total Quality Management for Restoring Competitiveness
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    • pp.325-332
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    • 1998
  • In the context of total quality management, customer satisfaction is a key factor of success. Customer needs have been in the past described with rather vague words. In order to lead in the competitive market, product designers must be willing to interpret and reflect customer perceptions of a product on the design. The objective of this research is to develop a systematic process capable of linking customer preferences on a product to the design of product elements or specifications. The design process consists of multivariate statistical analyses, semantic differentials, and multidimensional scaling techniques under the framework of a methodology known as quality function deployment which is frequently used to construct a quality design process. The process being established is expected to serve as an effective means to communicate between the customer and the designer through proper representational schemes of design elements.

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