• 제목/요약/키워드: analysis and design

검색결과 48,274건 처리시간 0.085초

태양에너지를 이용한 곡물건조시스템의 시뮬레이션에 관한 연구 (Simulation of Drying Grain with Solar-Heated Air)

  • 금동혁
    • Journal of Biosystems Engineering
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    • 제4권2호
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    • pp.64-64
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    • 1979
  • Low-temperature drying systems have been extensively used for drying cereal grain such as shelled corn and wheat. Since the 1973 energy crisis, many researches have been conducted to apply solar energy as supplemental heat to natural air drying systems. However, little research on rough rice drying has been done in this area, especially very little in Korea. In designing a solar drying system, quality loss, airflow requirements, temperature rise of drying air, fan power and energy requirements should be throughly studied. The factors affecting solar drying systems are airflow rate, initial moisture content, the amount of heat added to drying air, fan operation method and the weather conditions. The major objectives of this study were to analyze the effects of the performance factors and determine design parameters such as airflow requirements, optimum bed depth, optimum temperature rise of drying air, fan operation method and collector size. Three hourly observations based on the 4-year weather data in Chuncheon area were used to simulate rough rice drying. The results can be summarized as follows: 1. The results of the statistical analysis indicated that the experimental and predicted values of the temperature rise of the air passing through the collector agreed well.2. Equilibrium moisture content was affected a little by airflow rate, but affected mainly by the amount of heat added, to drying air. Equilibrium moisture content ranged from 12.2 to 13.2 percent wet basis for the continuous fan operation, from 10.4 to 11.7 percent wet basis for the intermittent fan operation respectively, in range of 1. 6 to 5. 9 degrees Centigrade average temperature rise of drying air.3. Average moisture content when top layer was dried to 15 percent wet basis ranged from 13.1 to 13.9 percent wet basis for the continuous fan operation, from 11.9 to 13.4 percent wet basis for the intermittent fan operation respectively, in the range of 1.6 to 5.9 degrees Centigrade average temperature rise of drying air and 18 to 24 percent wet basis initial moisture content. The results indicated that grain was overdried with the intermittent fan operation in any range of temperature rise of drying air. Therefore, the continuous fan operation is usually more effective than the intermittent fan operation considering the overdrying.4. For the continuous fan operation, the average temperature rise of drying air may be limited to 2.2 to 3. 3 degrees Centigrade considering safe storage moisture level of 13.5 to 14 perceut wet basis.5. Required drying time decrease ranged from 40 to 50 percent each time the airflow rate was doubled and from 3.9 to 4.3 percent approximately for each one degrees Centigrade in average temperature rise of drying air regardless of the fan operation methods. Therefore, the average temperature rise of drying air had a little effect on required drying time.6. Required drying time increase ranged from 18 to 30 percent approximately for each 2 percent increase in initial moisture content regardless of the fan operation methods, in the range of 18 to 24 percent moisture.7. The intermittent fan operation showed about 36 to 42 percent decrease in required drying time as compared with the continuous fan operation.8. Drymatter loss decrease ranged from 34 to 46 percent each time the airflow rate was doubled and from 2 to 3 percent approximately for each one degrees Centigrade in average temperature rise of drying air, regardless of the fan operation methods. Therefore, the average temperature rise of drying air had a little effect on drymatter loss. 9. Drymatter loss increase ranged from 50 to 78 percent approximately for each 2 percent increase in initial moisture content, in the range of 18 to 24 percent moisture. 10. The intermittent fan operation: showed about 40 to 50 percent increase in drymatter loss as compared with the continuous fan operation and the increasing rate was higher at high level of initial moisture and average temperature rise.11. Year-to-year weather conditions had a little effect on required drying time and drymatter loss.12. The equations for estimating time required to dry top layer to 16 and 1536 wet basis and drymatter loss were derived as functions of the performance factors. by the least square method.13. Minimum airflow rates based on 0.5 percent drymatter loss were estimated.Minimum airflow rates for the intermittent fan operation were approximately 1.5 to 1.8 times as much as compared with the continuous fan operation, but a few differences among year-to-year.14. Required fan horsepower and energy for the intermittent fan operation were3. 7 and 1. 5 times respectively as much as compared with the continuous fan operation.15. The continuous fan operation may be more effective than the intermittent fan operation considering overdrying, fan horsepower requirements, and energy use.16. A method for estimating the required collection area of flat-plate solar collector using average temperature rise and airflow rate was presented.

야산 기계화 개간공법에 관한 연구 -레이크 도저의 적정 이빨 간격의 선택과 발배근작업능률 시험(제1보)- (Research on Mechanized Upland Reclamation Works An Experiment for the Selection of Optimum Teeth Interval and the Analysis of Efficiency of Stumping and Root-Clearing Methods by Rake Dozer. (Report 1))

  • 류한열;정하우박승우
    • 한국농공학회지
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    • 제17권3호
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    • pp.3860-3871
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    • 1975
  • This experiment was carried out to establish the mechanized methods in stumping and root-clearing, which were the most important works in the reclamation of sloping uplands. The determination of optimum teeth interval of rake blades and its operation methods to reduce the quantity of transported topsoil during the works, are the aims of this investigation. A newly designed rake blade, whose net teeth intervals could be regulated by three stages as 15cm, 25cm, and 35cm, was manufactured to attach to the bulldozer of 13ton. The experiments were carried out at Kilsang-Myon, Kwangwha-Gun, from Aug. 9 to Aug. 23, 1975. For each interval, 36 test plots of 50${\times}$10mn in size, which were regulated under three levels of land slopes of 10, 20, and 30% and two different tree stand density of high or medium values, were randomly chosen and arranged by two-replicated split-split plot design. Each stump classified by its diameter was stumped and cleared by the rake dozer to be related between diameter and stumping time. The results obtained in this experiment can be summarized as follows: 1. Stumping times for the diameters ranging from 6 to 18cm of stumps are almost the same and they are not varied by the difference of teeth intervals of rake dozer. 2. By back-ward stumping method, the number of stumps which can be stumped per hour ranges almost from 100 to 170, showing significant difference with respect to the teeth intervals. The working area is sharply varied with not only the stand density of stumps but the teeth intervals. 3. Optimum stumping distance for each teeth interval of rake dozer to minimize the quantity of transported topsoil are varied with such the rates as it is 15m or 20m for 15cm of teeth interval, but 25m for 25cm or 35cm, respectively. The clearing distance could be chosen almost double as long as the operating distance. 4. The working areas per hour of the simultaneous stumping and clearing methods are no significant difference among the various treatments of working conditions, but they are affected by the operating techniques. However, the influencing factors of the working conditions as classified before and the working directions are ranged from 10 to 15 per cent of total working area, respectively. 5. The residual rates of stumps which are not stumped by the rake dozer in each test plot are generally reduced as the teeth interval gets narrower, but there are no significant difference among them. The mean residual rates average to be about 4% for the simultaneous stumping and clearing method. The back-ward stumping method are recommended to be supervised and directed by more than one man, to show the operator where the stumps are located. 6. The results according to the stumping and clearing methods are summarized as Table IV-2. And the selection of working methods is recommended to follow as shown in Fig. IV-9 with respect to the stand density of the field. 7. Generally speaking, the narrower the teeth interval, the better become the working results, but the more the quantity of transported topsoil is increased. Therefore, it is recommended that the teeth interval should be reduced from the present distance of more than 30cm to 25cm or 15cm, by developing suitable working methods through more field works and experiments.

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유방 자가 검진 참여 교육 프로그램이 유방 자가 검진 이행과 건강 증진 행위에 미치는 영향 (The Effects of the Breast Self-Examination Participant Education program on Breast Self-Examination Compliance and Health Promoting Behaviors in Adult Women)

  • 박은하;류은정;최경숙
    • 종양간호연구
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    • 제3권2호
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    • pp.133-144
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    • 2003
  • This study is carrying out a before and after experiment design for the non-equal comparative group to identify the effects of the breast self-examination education on breast self-examination participant education compliance and health promotion in women. The subject of this study was 58 women residing in Chungju. Their age ranged from 20 to 40. These women were not pregnant or did not breast feed, as well as they did not have any breast disease, at the time of survey. They were available for the response to the questionnaires, and understood the purpose of this study. They also agreed to participate in the study, and responded to the 3rd time questionnaires to the end. Thus, brochures and lectures were provided side by side to a group of 19 of those women, and only brochures were provided to another group of 39 of those women. With regard to education, a brochure and a program using a breast model were applied. Then, the frequency of the breast self examination compliance, breast self examination capability and the relations between the breast self examination and activities to promote health were measured, before the education, after 4 weeks of education and after 12 weeks of education. Before education and after 4 weeks of education. I collected the questionnaires myself visiting them, and after 12 weeks of education, the questionnaires were collected by mail. In relation to the study tool, the breast self examination activity was measured by two measuring tools: breast self examination activity frequency and breast self examination compliance capability. As for the frequency, the number of self examination for the period of 3 months, before the questionnaire survey, was measured in the form of self report. In relation to the tool to measure the breast self examination capability, the BSEPRI tool, which was developed by Wood in 1994, was used. Here, as the score was higher, the capability was indicated to be higher. The translated and revised version of Health Promoting Lifestyle Profile II (Walker, Sechrist & Pender. 2002) was used as a tool for health promotion. As the measured score was higher, the health promoting activity was indicated to be higher. The results of this study were as follows: 1. As a result of checking the breast self examination compliance frequency between the experiment group that received the breast self examination participant education and the comparative group that did not receive the education, there was a significant difference in interaction between groups by time, as time passed by. 2. As a result of checking the breast self examination compliance capability between the experiment group and the comparative group, there was a significant difference in interaction between groups by time, as time passed by. 3. As a result of carrying out a repetitive measurement analysis, between the experiment group that received the breast self examination education and the comparative group that did not receive the education, which was carried out to validate the hypothesis that the former would have higher health promoting activities than the latter, there was no significant difference after the breast self examination education was conducted.

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활성슬러지-인공습지 공법에 의한 돈사폐수처리시스템에서 오염물질의 분획별 정화효율 평가 (Evaluation of Treatment Efficiencies of Pollutants under Different Pollutant Fractions in Activated Sludge-Constructed Wetland System for Treating Piggery Wastewater)

  • 김성헌;서동철;박종환;이충헌;최정호;김홍출;하영래;조주식;허종수
    • 한국환경농학회지
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    • 제31권4호
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    • pp.344-350
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    • 2012
  • 돈사폐수의 분획별 및 우리나라 기후변화 특성에 대한 활성슬러지-인공습지 공법에 의한 돈사폐수처리장의 대응성을 검토하기 위하여 오염물질 분획별 및 계절별 수처리효율을 조사하였다. 오염물질 분획별 수처리효율을 조사한 결과 최종 방류수의 COD는 213.5 mg/L정도로 soluble형태가 71.5 mg/L, insoluble형태가 142 mg/L정도이었고, SS함량은 118 mg/L정도로 volatile형태가 102 mg/L, fixed형태가 15.5 mg/L정도이었으며, 최종 방류수의 T-N함량은 47.8 mg/L 정도로 dissolved형태가 12.8 mg/L, suspended형태가 35.0 mg/L정도이었다. 또한 방류수의 T-P함량은 3.05 mg/L정도로 dissolved형태가 1.13 mg/L, suspended형태가 1.93 mg/L정도이었다. 활성슬러지-인공습지 공법에 의한 돈사폐수처리장에서 계절별 수처리효율을 조사한 결과 COD, SS 및 T-P의 처리효율은 98, 99 및 99%이상으로 계절에 따라 별 다른 차이 없이 높은 처리효율을 보였고, T-N 처리효율은 여름 (99.5%)${\geq}$가을 (99.1%)${\geq}$겨울 (98.7%)${\geq}$봄 (98.2%)의 순으로 여름철에 가장 높은 처리효율을 보였다.

여대생의 체질량지수, 다이어트 인식과 다이어트 행동에 관한 연구 (A Study on BMI, Diet Perception and Dietary Behavior of Female University Students)

  • 이진희
    • 한국응용과학기술학회지
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    • 제37권3호
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    • pp.463-472
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    • 2020
  • 본 연구는 여대생의 체질량지수와 다이어트 인식 및 다이어트 행동에 관해 알아보기 위해 시행된 서술적 조사연구이다. 연구 대상자는 일 지역 여자대학교에 재학 중인 학생 165명으로 자료수집은 2018년 10월 29일부터 11월 9일까지 진행되었다. 수집된 자료의 분석은 SPSS/WIN 21.0 프로그램을 이용하여 기술통계, t 검정, 일원분산분석, 교차분석을 하였다. 전체 다이어트 인식은 3.44점이었고 요인별로는 '실행'이 4.00점으로 가장 높게 나타났고, 그 다음으로 '정보 및 교육'이 3.58점, '필요성'은 3.32점, '자가인식'은 2.84점으로 가장 낮게 나타났다. 다이어트 횟수는 '3회 미만'이 65명(43.0%)으로 가장 많았으며 방법은 '음식조절'이 65명(43.0%), '운동'이 62명(41.1%) 순이었다. 일주일간 운동시간은 3시간 미만이 99명(65.6%)으로 가장 많았고 '전혀 하지 않는다'가 32명(21.2%)으로 그 다음 순이었다. 다이어트로 인한 피해경험은 22명(14.6%)이 있다고 응답했고, 종류로는 위장병, 생리불순, 탈모 등이었다. BMI에 따른 다이어트 인식 전체 점수는 저체중군이 정상체중 및 과체중군보다 점수가 낮게 나타났다(p<.001). 하부 요인별로 보면 다이어트 '실행'은 저체중군이 정상체중 및 과체중군보다 점수가 낮게 나타났고(p<.05), 다이어트 '정보 및 교육'은 과체중군의 점수가 가장 높았고, 그 다음이 정상체중군, 저체중군 순이었다(p<.001). 다이어트 '필요성'과 '자가인식'은 저체중군이 정상체중 및 과체중군보다 점수가 낮게 나타났다(p<.001). 다이어트 인식에 따른 다이어트 행동은 다이어트 횟수와 방법에서 차이가 있었다(p<.001). 본 연구 결과를 토대로 여대생의 올바른 다이어트 인식 형성과 건강한 생활유지를 위한 관심과 교육이 필요하다고 사료된다.

학교폭력 예방을 위한 중학교 가정과 교육 프로그램 개발 - 실천적 행동 수업 모형을 적용하여 - (The development of Home Economics Education program for the prevention of school violence in middle school : Based on the Practical Action Teaching Model)

  • 손주영;채정현
    • 한국가정과교육학회지
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    • 제25권2호
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    • pp.103-128
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    • 2013
  • 본 연구의 목적은 가정과 교육을 통해 학교폭력을 예방하기 위한 방안으로 실천적 수업모형을 적용하여 중학생 대상의 학교폭력 예방 교육 프로그램을 개발하는 데 있다. 이러한 연구 목적을 달성하기 위하여 ADDIE 모형을 토대로 재구성하여 분석, 설계, 개발, 평가의 과정에 따라 연구를 진행하였다. 분석 단계에서는 학교폭력 예방 프로그램 개발을 위한 기초 연구를 수행하였다. 학교폭력 발생에 영향을 주는 위험요인과 보호요인, 국내외 학교폭력 예방 프로그램에 대한 핵심 구성요소, 구성 원리, 목표 및 실제 프로그램의 적용 방법 등을 파악하고, 프로그램 적용 모형으로 Laster의 실천적 행동 수업 모형(Practical Action Teaching Model)에 대한 선행연구를 고찰하였다. 설계 단계에서는 학교폭력 예방 프로그램을 위한 개발 방향 및 구성 개요를 설정하였다. 학교폭력 예방 보호요인과 가정교과 내용과의 관련성을 고려하여 프로그램의 내용요소를 선정하고, 국내외 학교폭력 예방 프로그램의 분석을 토대로 프로그램의 설계 방향을 설정하였다. 또한, 전체 프로그램의 목적 및 영역별 목표, 영역별 실천적 문제와 학습목표를 진술하고 주요 활동 내용을 설계하였다. 개발단계에서는 실천적 행동 수업모형을 적용한 주제별 교수 학습 과정안과 학습 자료, 교사용 참고자료 및 프로그램 타당도 검증을 위한 평가도구를 개발하였다. 평가 단계에서는 가정과교육 전문가 10인을 대상으로 프로그램 타당도 검사를 설문지를 이용하여 실시하였다. 개발된 학교폭력 예방을 위한 가정과 교육 프로그램은 학교폭력 인식변화, 자아존중감 향상, 타인과 관계 맺기, 배려와 나눔의 실천, 폭력예방 실천의지 다지기의 5개 영역으로 구성하였다. 또한, 이 5개 영역 당 1~2개씩 총 7개의 실천적 문제(서로 돕고 배려하는 친구관계 형성을 위해 나는 무엇을 해야 하는가?, 긍정적인 자아개념을 형성하기 위해 나는 무엇을 해야 하는가?, 원만한 관계를 형성하는 의사소통을 하기 위해 나는 무엇을 해야 하는가?, 갈등을 평화적으로 해결하기 위해 나는 무엇을 해야 하는가?, 배려와 나눔의 식생활을 실천하기 위해 나는 무엇을 해야 하는가?, 배려와 나눔의 의생활을 실천하기 위해 나는 무엇을 해야 하는가?)로 나누어 총 24차시로 개발되었다. 실천적 문제에 따라 문제인식, 실천적 추론, 행동, 평가의 4단계를 거치는 실천적 행동 수업 모형을 적용하였으며 각 단계마다 추론을 위한 질문을 제시하였고 실천행동이 이루어질 수 있도록 다양한 활동 과제를 제시하였다. 학습 자료는 학생용 자료와 교사용 참고자료로 나누어 개발하였다. 실천적 추론활동 과정에서 수업에 대한 이해를 돕고 흥미를 증진시키기 위해 개발된 학생용 자료는 활동지, 읽기, 동영상, 그림 자료 등으로 총 80편이 개발되었다. 교사용 참고자료는 관련 이론 및 신문자료, 동영상 자료 등으로 총 35편이 개발되었다. 실천적 행동 수업 모형을 적용하여 개발한 학교폭력 예방 가정과 교육 프로그램에 대해 현장교육의 유용성, 현장에서의 실행 가능성, 학습내용과 자료의 적합성 및 충실성, 교수 학습 과정안과 학습 자료의 내용타당도 검사를 실시한 결과 평균 4.36점 이상의 긍정적인 평가 결과를 얻을 수 있었다. 이를 근거로 볼 때 본 프로그램은 학교현장에서 학교폭력 예방 교육에 효과적이며 유용하게 사용될 수 있을 것으로 기대된다.

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공정부산물의 방사선적 특성과 처분방안에 관한 기본 연구 (A Basic Study on the Radiological Characteristics and Disposal Methods of NORM Wastes)

  • 정종태;백민훈;박정균;박태진;고낙열;윤기훈
    • 방사성폐기물학회지
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    • 제12권3호
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    • pp.217-233
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    • 2014
  • 생활주변방사선안전관리법 도입에 따라 재활용하지 못하는 공정부산물의 안전관리를 위해서는 방사선적 안전성 확보가 필수적이다. 이를 위해서 처분대상 공정부산물 특성화 자료 수집 및 분석, 처분방법과 처분시설의 조사 및 분석, 처분시설의 운영으로 인한 방사선적 안전성평가 방법론 정립과 도구 확보, 주요 입력자료들의 안전성에 미치는 영향 파악 등이 필요하다. 이를 통하여 매립과 같은 참조 처분방법을 선정하고 피폭선량과 인체보건 리스크 평가를 통하여 공정부산물 처분에 따른 방사선적 안전성 확보를 위한 절차 및 기준마련을 위한 기술적 근거를 확보할 필요가 있다. 본 연구에서는 공정부산물 처분방법과 공정부산물 처분시설에 대한 국내외 현황 조사 및 분석과 국내외 주요 산업별 처분대상 공정부산물 특성화 자료 수집 및 분석을 수행하였다. 이를 바탕으로 주요 공정부산물 특성에 따른 관리방안과 매립 처분시설에 대한 개념설계를 제안하였다. 또한, 공정부산물 처분시 대기확산에 의한 방사성핵종의 전이경로와 침출수 유출로 인한 방사성핵종의 전이경로 파악을 수행하고 적절한 코드를 선정하여 예제 평가를 수행함으로써 코드의 유용성을 확인하였다. 그리고 국내 대표 공정부산물인 비산재, 인산석고, 레드머드 특성화 자료를 이용하여 공정부산물 처분시 피폭선량 및 초과 암 리스크를 평가하고 분석하였다. 개념적 설계 예제에 대한 방사선적 안전성 평가 결과에 의하면 공정부산물 처분시 피폭선량 및 초과 암 리스크는 매우 낮은 값을 가지며 우려할 만한 방사선적 영향을 보이지는 않는다. 연구결과는 향후 생활방사선 안전관리를 위한 규제기술 개발에 활용 가능할 뿐만 아니라 생활주변방사선안전관리법 이행기술 기반 구축에 기여할 수 있을 것이다.

서비스 종업원의 표면행위가 반생산적 과업행동에 미치는 효과에 관한 연구: 감정소모의 매개효과를 중심으로 (The Effects of Service Employee's Surface Acting on Counterproductive Work Behavior: The Mediating Roles of Emotional Exhaustion)

  • 강성호;최종학;이지애;허원무
    • 유통과학연구
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    • 제14권2호
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    • pp.73-82
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    • 2016
  • Purpose - Counterproductive work behavior(CWB) was typically categorized according to the behavior whether it targets other people(i.e., interpersonal CWB: I-CWB). Employing organizations(i.e., organizational CWB: O-CWB) has emerged as major concerns among researchers, managers, and the general public. An abundance of researches has informed us about the understanding for the antecedents of CWB, whereas little is known about the antecedents of CWB directed distribution service in employee's emotional labor. Therefore, the purpose of this research is to propose a research model in which surface acting enhances emotional exhaustion as an emotional labor strategy, which eventually increases counterproductive work behavior(including I-CWM and O-CWB). Research design, data, and methodology - This empirical research data were gathered from the samples of full time frontline hotel employees(including front office, call center, food/beverage, concierge, and room service) in South Korea. Six hotels were selected ranged from four to five stars, including privately owned and joint-venture properties. A convenience sampling method was used to select hotels. Full time frontline hotel employees from the six hotels were surveyed using a self-administered instrument for data collection. With the strong support of hotel managers, a total of 300 questionnaires were distributed, and 252 responses were collected indicating a response rate of 84.0%. In the process of working with the 252 samples, structural equation modeling is employed to test research hypotheses(H1: The relationship between surface acting and Interpersonal counterproductive work behavior(I-CWB) is mediated by emotional exhaustion, H2: The relationship between surface acting and organizational counterproductive work behavior(O-CWB) is mediated by emotional exhaustion). SPSS 18.0 and M-Plus 7.31 software were used for the data analysis. Descriptive statistics were used to assess the distribution of the employee profiles and correlations between factors. M-Plus 7.31 software was used to test the model fit, validity, and reliability of the factors, significance of the relationship between factors, and the effects of factors in the model. Results - To test our mediation hypotheses, we used an analytical strategy suggested by Preacher & Hayes (2008) and Shrout & Bolger (2002). This mediation approach directly tests the indirect effect between the predictor and the criterion variables through the mediator via a bootstrapping procedure. Thus, it addresses some weaknesses associated with the Sobel test. We found that surface acting was positively related to emotional exhaustion. Furthermore, emotional exhaustion was a significant predictor from the two kinds of counterproductive work behavior. In addition, surface acting was not significantly associated with the two kinds of counterproductive work behavior. These results indicated that the surface acting by frontline hotel employees was associated with higher emotional exhaustion, which is related with higher interpersonal counterproductive work behavior(I-CWB) and organizational counterproductive work behavior(O-CWB). In sum, we confirmed that the positive relationship between surface acting and the two kinds of counterproductive work behavior was fully mediated by emotional exhaustion. Conclusions - The current research broadens the conceptual work and empirical studies in counterproductive work behavior literature by representing a fundamental mechanism that how surface acting affects counterproductive work behavior.

유리 견갑 피판 이식술 (Scapular Free Flap)

  • 정덕환;한정수;임창무
    • Archives of Reconstructive Microsurgery
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    • 제5권1호
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    • pp.24-34
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    • 1996
  • There are many kinds of free flaps for management of extensive soft tissue defect of extremities in orthopaedic field. Free vascularized scapular flap is one of the most useful and relatively easy to application. This flap has been utilize clinically from early eighties by many microsurgical pioneers. Authors performed 102 cases of this flap from 1984 to 1995. We have to consider about the surgical anatomy of the flap, technique of the donor harvesting procedures, vascular varieties and anatomical abnormalities and success rate and the weak points of the procedure. This flap nourished by cutaneous branches from circumflex scapular vessels emerges from the lateral aspect of the subscapular artery 2.5-5cm from its lateral origin passing through the triangular space(bounded by subscapularis, teres minor, teres major, long head of triceps). The terminal cutaneous branch runs posteriorly around the lateral border of the scapular and divided into two major branches, those transeverse horizontally and obliquely to the fascial plane of overlying skin of the scapular body. We can utilize these arteries for scapular and parascapular flap. The vascular pedicle ranged from 5 to 10 cm long depends on the dissection, usually two venae comitantes accompanied circumflex scapular artery and its major branches. The diameter of the circumflex scapular artery is more than 1mm in adult, rare vascular variation. Surgical techniques : The scapular flap can be dissected conveniently with prone or lateral decubitus position, prone position is more easier in my experience. There are two kinds of surgical approaches, most of the surgeon prefer elevation of the flap from its outer border towards its base which known easier and quicker, but I prefer elevation of the flap from its outer border because of the lowering the possibilities of damage to vasculature in the flap itself which runs just underneath the subcutaneous tissue of the flap and provide more quicker elevation of the flap with blunt finger dissection after secure pedicle dissection and confirmed the course from the base of the pedicle. There are minimal donor site morbidity with direct skin closure if the flap size is not so larger than 10cm width. This flap has versatility in the design of the flap shape and size, if we need more longer and larger one, we can use parascapular flap or both. Even more, the flap can be used with latissimus dorsi musculocutaneous flap and serratus anterior flap which have common vascular pedicle from subscapular artery, some instance can combined with osteocutaneous flap if we include the lateral border of the scapular bone or parts of the ribs with serratus anterior. The most important shortcoming of the scapular free flap is non sensating, there are no reasonable sensory nerves to the flap to anastomose with recipient site nerve. Results : Among our 102 cases, overall success rate was 89%, most of the causes of the failure was recipient site vascular problems such as damaged recipient arterial conditions, and there were two cases of vascular anomalies in our series. Patients ages from 3 years old to 62 years old. Six cases of combined flap with latissimus dorsi, 4 cases of osteocutaneous flap for bone reconstruction, 62 parascapular flap was performed - we prefer parascapular flap to scapular. Statistical analysis of the size of the flap has less meaningful because of the flap has great versatility in size. In the length of the pedicle depends on the recipient site condition, we can adjust the pedicle length. The longest vascular pedicle was 14 cm in length from the axillary artery to the enter point cutaneous tissue. In conclusion, scapular free flap is one of the most useful modalities to manage the large intractable soft tissue defect. It has almost constant vascular pedicle with rare anatomical variation, easy to dissect great versatility in size and shape, low donor morbidity, thin and hairless skin.

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구동팬텀 시스템에 의한 움직이는 장기의 선량분포 분석 (Analysis of the Dose Distribution of Moving Organ using a Moving Phantom System)

  • 김연래;박병문;배용기;강민영;이귀원;방동완
    • 대한방사선치료학회지
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    • 제18권2호
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    • pp.81-87
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    • 2006
  • 목 적: 움직이는 장기의 방사선치료시에 움직임을 고려한 선량분포의 연구가 많이 이루어지지 않았고, 정적인 상태로서의 선량분포가 고려된 치료 및 연구가 이루어졌다. 그래서 본 연구는 구동팬텀 시스템을 이용하여 움직이는 장기의 선량분포 계측을 시행하였다. 이 연구의 목적은 호흡에 따른 선량분포의 변화가 어떻게 일어나는지에 대한 실험적 계측에 대한 평가이다. 재료 및 방법: 호흡에 의한 움직이는 장기의 선량분포 측정을 위해서 다목적 팬텀과 구동팬텀을 고안 하였다. 다목적 팬텀의 구성은 아크릴과 코르크를 사용하였고, 아크릴의 밀도는 $1.14g/cm^3$이고 코르크는 $0.32g/cm^3$이다. 아크릴은 정상조직을 표현하기 위해 사용되었고, 코르크는 폐를 묘사하기 위해 제작 되었다. 측정용 필름은 가프크로믹 필름과 EDR2필름을 사용하였다. 구동팬텀 시스템은 상하좌우 2차원적인 움직임을 하도록 설계되었으나 본 실험은 1차원적인 움직임만으로 구동하여 측정하였다. 결 과: 코르크 팬텀에서 측정된 선량분포가 아크릴에서 측정된 선량분포보다 반음영이 크게 나타났다. 가프크로믹 필름으로 측정된 선량분포는 선량분포에 따른 광학농도가 낮기 때문에 분포곡선이 평탄하지 않았다. 내부장기의 움직임이 증가함에 따라 선량분포에서 반음영, 평탄도, 대칭도가 점점 증가하였다. 모든 가프크로믹 필름으로 측정된 선량분포는 EDR2필름으로 측정된 필름보다 평탄도나 대칭도가 좋지 않았지만 반음영은 비슷하게 분포되었다. 결 론: 가프크로믹 필름은 현상이 필요 없기 때문에 사용하기 편하고, 조그만 크기로도 쉽게 잘라서 사용할 수 있다. 또한 많은 양의 방사선을 조사할 수 있는 장점이 있다. 그러나 선량에 따른 광학농도의 변화가 작기 때문에 측정 시에 선량분포에 평탄도가 좋지 않다. 움직이는 장기의 방사선치료시 다목적 팬텀과 구동팬텀을 이용하여 질보정이 이루어진다면 치료효과를 향상시킬 것이라 사료된다.

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