• 인터넷정보학회논문지
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• 제22권3호
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• pp.1-8
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• 2021

가상 현실 공간에서 head-mounted display(HMD)를 통한 실감형 미디어를 제공하기 위해서는 초고화질 및 초고해상도의 전방위 360도 영상 전송이 필요하고, 이는 높은 대역폭 및 연산량을 요구한다. 이를 극복하기 위해 360도 영상에 대한 타일 기반 분할 기법을 사용하여 사용자 시점 기반 선택적 스트리밍 기법이 사용될 수 있다. 본 논문은 16K 초고화질 360도 영상 및 종래에 널리 쓰이는 4K 360도 영상에서의 사용자 시점 기반 타일 스트리밍 기법의 성능 평가를 소개한다. 16K 초고화질 360도 영상에 타일 스트리밍 기법을 적용하였을 때, 영상 전체 부호화 및 전송 방법 대비 42.47%의 bjotegaard delta rate(BD-rate) 절감을 확인하였고, 4K 360도 영상 타일 스트리밍 시 26.41%의 BD-rate 절감이 이루어지는 것을 확인하였다. 따라서, 타일 스트리밍이 초고해상도 영상에 더 효율적임을 확인하였다.

• 설비공학논문집
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• 제18권1호
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• pp.47-54
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• 2006

[ $CO_2$ ] and propane mixtures were chosen as promising alternative refrigerants and their performance potentials were evaluated experimentally in an air-conditioning system. Pure $CO_2$ and 85/15, 75/25 and 60/40 binary blends by the charged mass percentage of $CO_2/propane$ were selected as working fluids. The effect of the inlet temperature of the secondary fluids and degree of superheat on the cooling performance was tested and discussed. The charging amounts of refrigerants were adjusted to make the system show the maximum COP. Comparisons among different refrigerants were carried out on the same compressor speed basis for a given operating condition. In addition, the temperature gliding effect of zeotropic mixtures on the system performance were analyzed based on the drop-in test results.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2011년도 제37회 추계학술대회논문집
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• pp.389-392
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• 2011

본 연구에서는 틸트로터 비행체인 스마트무인기의 비행시험에서 엔진성능 데이터를 추출하고 분석하였다. 비행시험은 프롭로터의 틸트각이 90도에서 0도로 변화하고 다시 0도에서 90도로 변환하는 천이비행 영역에서 이루어졌다. 비행시험으로부터 수집된 엔진성능 데이터로서 엔진 동력과 비연료 소모율은 엔진성능계산프로그램의 예측결과와 잘 일치하였다.

• 경영과학
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• 제29권2호
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• pp.167-184
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• 2012

Business diversification is inevitable to survive under the current competitive business environments. The advent of new businesses makes corporate governance more complicated through corporate combinations. Recent introduction of new accounting standard, International Financial Reporting Standards(IFRS), accelerates the need for corporate governance analysis. This study analyses the complex corporate governance system and its relation to the business performance using social network analysis. Corporate inter-governance networks can be visualized easily in a social network diagram. 552 corporate governance data are empirically analysed in the Korean stock market. The changes in In-Degree between networks are positively related with the changes in corporate sales volume. We can find the same results using operating profits as corporate performance proxy. The results show that social network analysis technique can be applied to investments in the stock markets.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1996년도 한국자동제어학술회의논문집(국내학술편); 포항공과대학교, 포항; 24-26 Oct. 1996
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• pp.1040-1043
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• 1996

The accuracy of the servo control in CNC system has a great influence on the duality of machine product. Tracking performance of the servo control is deteriorated mainly by the time delay of the servo system and the inertia of the work table or bed. Contouring errors occur in every interpolation steps by the effect of the tracking performance. In this paper, $H_{\infty}$ two-degree-of-freedom(TDF) controller is designed for improvement to improve the tracking performance. The designed controller is applied 3-axis machining center model and the cutting accuracy is simulated in case of corner cutting, circular and involute interpolation. Simulation results show that $H_{\infty}$ TDF controller designed in this paper has a good effect to improve tracking performance in CNC system.

• Journal of Information Technology Applications and Management
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• 제23권2호
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• pp.113-141
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• 2016

This study identifies and validates the factors that affect sales performance of salespersons in the business software industry. In the study, in order to measure the dependent variable (performance of the salesperson) more comprehensively, multiple items are utilized and both outcome and behavior indicators are used. Independent variables are identified based on the classification of Verbeke et al. [(2011] including sales related knowledge, degree of adaptiveness, role ambiguity, and work engagement. Results of the hypotheses testing show that 'sales related knowledge' and 'work engagement' are statistically significant factors, but 'degree of adaptiveness' and 'role ambiguity' are not. This study has a few limitations and future research direction to overcome the limitation is suggested : use of both perceptions of the salesperson and objective measures in measuring the related variables; study including cognitive ability; analyses of the factors across various types of software companies; and analyses of the factors on the team level.

• 설비공학논문집
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• 제24권9호
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• pp.699-703
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• 2012

The performance of the typical VAV dampers; blade type, venturi type and blade-orifice type, for the circular duct, is obtained by measuring the volume flow rate as a function of the opening degree. The performance features are discussed by comparing the volume flow rate of each damper. It is shown that the blade-orifice type damper, recently developed, is excellent in its linearity of the performance and that it is worse than the blade type but much better than the venturi type in its flow resistance.

• 한국의료질향상학회지
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• 제25권2호
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• pp.56-72
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• 2019

Purpose: The purpose of this study was to determine the factors that influence the performance and importance of clinical nutritionists. Methods: Ninety-nine nutritionists working in mental health institutions were assessed. Results: Factors affecting the performance of clinical nutritionists in certified hospitals were shown to have a significant positive effect on the description of treatment diet, status of clinical nutrition management, and presence of a nutrition counselor. The factors affecting importance were the number of permission beds and total work experience. Conclusions: In order to improve the accreditation system of mental hospitals, it is necessary to expand the scope of this study to include hospitals with fewer beds, and clinical nutrition management should be mandatory.

• Child Health Nursing Research
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• 제3권1호
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• pp.52-61
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• 1997

This study was attempted to identify the knowledge to breast-feeding and the performance of nursing activities for breast-feeding and to test 'how does the degree of knowledge to breast-feeding influence the nursing activities for breast-feeding?' The subjects were 180 nurses working in delivery rooms, nursery, obstetrics & pediatrics wards or OPD of obstetrics & gynecology of 8 general hospitals in Pusan as of August 3 through 13, 1996. The results are abstracted as follows. 1) Subject nurses' age, 25-29 was 45.6%(the major), education levels graduates from junior college were 95.0%, unmarried status was 62.2%, 76.5% of married nurses had children, 39.7% in-service education for Breast-Feeding, 33.7% did nursing activities for breast-feeding actively, the reason for inadequate activities for breast-feeding was 'too much other tasks.' 2) The degree of knowledge to breast-feeding ; mean score was 13.54, the degree of performance of nursing activities for breast-feeding : 92.38±20.93 points out of possible 145 points (3.19±.74 out of possible 5 points) moaned that it was a low level. 3) The hypothesis 'the nurses who have higher degrees of knowledge to breast-feeding will show higher degrees of performance of nursing activities for breast-feeding than the nurses who have lower degrees of knowledge to breast-feeding' was tested by t-test(t=-.01, P=.9888), but rejected because it turned out statistically not significant at the level of P<.05. Above results suggested the degrees of knowledge to breast-feeding and the degrees of performance of nursing activities for breast-feeding were generally low and the degree of knowledge didn't influence the nursing activities. Researchers believe that the education for breast-feeding by the nurses need to be performed systemically & practically and new method of breast-feeding education program need to include hospital managers as well as nurses related mothers and their family. In audition, researchers propose the introduction of &lactation specialist system&, for the specialist can change the attitude of feeding-mothers positively with their specialty and authority.

• 한국간호교육학회지
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• 제6권2호
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• pp.262-275
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• 2000

This study was done to describe the health promoting behavior and the quality of life among climacteric women and to identify the factors affecting the performance in health promoting behavior and the level of quality of life among climacteric women. The subjects of this study were 171 women(40 to 60 years old). The sample data were collected using a convenient sampling method, collected from August 10th to September 20th, 2000. The instruments for this study were the health promoting behavior scale(Park, 1995), the quality of life scale(No, 1988). Frequency, percentage, t-test, ANOVA, Pearson's correlation with SPSS program were used to analyze the data. The results of the study were as follows; 1) The average score of the performance in the health-promoting behavior variables was 2.594. The variable with the highest degree of performance was the sanitary environment, whereas the one with the lowest degree was the professional health maintenance. 2) The average score of the level in the quality of life variables was 3.069. The variable with the highest degree was the relationship with neighbor, whereas the one with lowest degree was the economic life factor. 3) Performance in the health- promoting behavior was positively related to the level in the quality of life(r=0.54, P=0.001). 4) A significant difference was demonstrated between educational level, income, perceived health status and health-promoting behavior. 5) A significant difference was demonstrated between perceived health status and quality of life.