• 유공압시스템학회:학술대회논문집
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• 유공압시스템학회 2010년도 춘계학술대회
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• pp.126-131
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• 2010

In order to improve the life and reliability of fluid components used in the Automotive, Hydraulics and Aerospace industries, the cleanliness of the system parts and components before their assembly into the system is being addressed. The measurement of components and parts cleanliness is related to contaminant collection, analysis and data reporting and ISO Standard are continually being developed to control procedures. This Paper explains the processes in these standards and explains how similar procedures have been adapted to suit the requirements of the respective Industry. It also gives guidance and recommendations on the implementation of these standards, so that best use can be made of them.

• Nutritional Sciences
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• 제8권2호
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• pp.140-147
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• 2005

In order to promote foodservice for older adults, foodservice directors in Continuing Care Retirement Communities (CCRCs) must identify the dimensions used by residents to evaluate the service quality of dining service. A multidimensional measure of perceived service quality was developed based on residents' responses about their experiences with dining service. A survey was administered to residents in two CCRCs. Based on the results of principal component analysis, this study identified four dimensions: food quality, dining room employee's attitude and service skills, dining room employee's safety and cleanliness, and systemization of service delivery process. A new dimension that reflects residents' concern for the dining mom employees' safety and cleanliness also emerged. 1bis study points to areas of improvement for food quality and dining room employee's safety and cleanliness.

• Korean Chemical Engineering Research
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• 제47권6호
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• pp.688-694
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• 2009

PCB의 먼지 제거용 세정제로 사용되는 스프레이형 세정제를 선정하여 이에 대한 청정도를 평가하였다. 친환경적인 대체 세정제를 채택하기 위해서는 세정제의 세정성, 환경성, 경제성을 평가하여 체계적인 선정절차에 의거하여 도입 및 적용하여야 한다. 객관적이고 효율적인 세정성 평가방법의 정립이 현시점에서 매우 중요하다. 본 연구에서는 여러 세정성 평가 방법들 중 표면관찰평가법인 SEM-EDX(Scanning Electron Microscopy/Energy-Dispersive X-ray) 분석과 적외선열화상카메라(THERMOVISION A20 model)를 이용하여 청정도를 평가하였다. CT-2770 모델의 사운드카드를 $2{\times}2cm$로 잘라내어 스프레이 세정 전과 후의 청정도를 SEM의 이미지 분석을 통해 관찰할 수 있었고 EDX의 성분분석을 통해 먼지의 제거율을 정량화할 수 있었다. 컴퓨터의 P4T-E 모델의 마더보드와 IPC-A-36 모델의 기판을 사용, 오염물로 먼지와 철가루를 사용하여 열화상카메라로 세정 전, 후의 상온과 $50^{\circ}C$ Oven에 방치된 시간의 차이에 따른 온도의 변화를 비교하였다.

• 한국주조공학회지
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• 제22권3호
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• pp.130-136
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• 2002

The growing use of aluminum for castings over the past decade has brought with it the increased scrutiny of component properties. One area that has received much attention is the effect of in inclusions - or impurities particles held in the metal - on casting properties. A new method of electromagnetic separation for removal of inclusions in aluminum alloy melts is proposed. The principle is that as the electromagnetic force induced in metal acts on inclusions due to low electric conductivity, they are moved to the direction opposite to electromagnetic force and can be separated and removed from the melt. Experiments were carried out on A356 melt mixed alumina particles and commercial Al alloys of ADC 10 and 12. In the experiment using A356, it was proved that $Al_2O_3$ particles was separated and removed continuously from matrix melt by electromagnetic force. Based on these results, the continuous separation experiment that used ADC 10, 12 was carried and the cleanliness of melt was assessed by the amount of porosity, hydrogen contents, PoDFA and mechanical properties through tensile test. As the results of analyses, the amount of porosity and hydrogen contents decreased without variation of chemical composition in the specimen that passed the electromagnetic continuous separator. In addition, tensile strength and elongation of this specimen increased by $20{\sim}30%$ because of reduction of inclusions.

• 동력기계공학회지
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• 제19권1호
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• pp.83-89
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• 2015

A ball strainer screen module, which is used for a condenser tube cleaning system, is a critical mechanical component for maintaining condenser cleanliness. Despite of this importance, not many research have been focused on this module because of its relatively low usage. Employing CFD, this study examines the implication of fluid velocity change and blockage ratio on the ball strainer screen velocity and the static pressure distribution. Through this study, the impact of blockage in the space between ball strainer screen modules is verified. Also, it is found that the ranges of non-dimensional velocity distribution and static pressure distribution decrease as blockage ratio becomes smaller.

• 한국펄프종이공학회:학술대회논문집
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• 한국펄프종이공학회 2003년도 제29회 펄프종이기술 국제세미나
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• pp.87-105
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• 2003

A new polymer technology commercialized with the name of Core Shell has been developed by Ondeo Nalco Company. Laboratory evaluations have demonstrated that Core Shell polymers produce a floc with high shear resistance, making them the flocculants of choice for modern high-speed paper machines. Core Shell polymers provide significant papermaking benefits, when used as single component or in combination with microparticles. At this time, the new program has been successfully applied on more than 60 paper and board machines across the world. Implementation of Core Shell polymers with or without a microparticle provided better and more stable retention values and improvements in paper quality, system cleanliness and machine runnability.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2007년도 추계학술대회 논문집
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• pp.391-394
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• 2007

Wind turbine gearbox is a complex mechanical system that includes gear trains, shafts, bearings, and gearbox housings. All these components are interacting with each other therefore it is important to assess the whole performance by considering the individual component design. In this paper, the performance assessment of 2MW wind turbine gearbox was conducted under various operating conditions at test bench and test result was compared with the design calculation.

• 한국가정과교육학회지
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• 제22권2호
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• pp.1-13
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• 2010

본 연구는 중고 청소년을 대상으로 하여 외모에 대한 태도의 정도가 교우 및 교사와의 관계, 학습 적응 정도, 그리고 교칙준수와 같은 전반적인 학교생활에 어떠한 영향을 미치는지 파악함으로써 학교생활 지도와 가정 교과의 의생활 영역의 기초자료를 얻고자 하였다. 조사대상자는 광주광역시 남, 여 중 고등학생을 대상으로 설문조사를 실시하였으며 총 481부를 최종 자료로 사용하였다. 자료 분석은 통계패키지 SPSS/PC WIN 14.0 프로그램을 사용하였으며, 연구문제를 해결하기 위해 기술 통계, t-검증, 일원배치 분산분석(One-Way ANOVA), Duncan-test, 신뢰도 분석(Cronbach's ${\alpha}$), 요인분석(Varimax 회전), Pearson의 상관 분석, 중다회귀분석을 실행하였다. 본 연구를 통해 얻어진 결과를 종합해 보면 학교적응을 위해서는 청결관리를 강조하여 생활지도가 이루어져야 할 것이며 교우 관계의 적응을 위해서는 친구들 사이에 유행하는 스타일 추구나 외모관리경험을 허용하는 것도 도움이 될 것이다. 또한 학교 규율 적응을 위해서는 외모불만을 조절하고 청결관리를 강조하며 학습적응을 위해서는 청결관리를 강조하되 최신 유행을 따르며 교복을 변형하는 등의 스타일추구를 제한하는 것이 도움이 될 것으로 생각된다. 특히 성적이 중하위권 이하인 여자 고등학생의 교사와의 관계, 학교규율 적응과 학습적응을 위해서는 스타일추구나 외모관리감정을 조절할 수 있도록 지도하며 도움을 줄 수 있는 프로그램의 개발이 필요하다.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2007년도 춘계학술대회B
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• pp.3270-3275
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• 2007

DME (Dimethyl Ether, $CH_3OCH_3$) has highly attracted attention as an alternative fuel for transportation, power generation and LPG substitute owing to its easy transportation and cleanliness. This study was conducted to verify the combustion performance and to identify potential problems when DME is fuelled to a gas turbine. GE7EA gas turbine of Pyong-Tak power plant was selected as a target to apply the DME. Combustion tests were conducted by comparing DME with methane, which is a major component of natural gas, in terms of combustion instability, $NO_X$ and CO emissions, and the outlet temperature of the combustion chamber. The results of the performance tests show that DME is very clean but has a low combustion efficiency in low load condition. From the results of the fuel nozzle temperature we have ascertained that DME is easy to flash back, and this property should be considered when operating a gas turbine and retrofitting a burner.

• 대한지역사회영양학회지
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• 제5권1호
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• pp.83-91
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• 2000

The aims of this study are to evaluate the quality of hospital food services and the evaluate the quality in selected hospitals trough the use of the questionnaires. A survey of 30 hospital food and nutrition service department was undertaken and detailed information was collected from each, including, surveys of 1, 016 patient. Statistical data analysis was completed using the SAS/win 6.11 package for descriptive analysis, t-test X$^2$-test ANOVA principal component analysis , and cluster analysis and cluster analysis. In the case of patient satisfaction with hospital food and food services, overall satisfaction scores of male and female were 3.54 and 3.45 showing higher levels than the average score(3.00) The aspect of the food and food service which received the lowest ratings by patients was 'meal rounding while dining'. After conduction of factor analysis of variables affecting the patients meal satisfaction 3 groups including the 'menu satisfaction factor', 'service satisfaction factor ' and 'nutrition management satisfaction factor ' were selected. 3 clusters were categorized by the 'service cluster' 'nutrition management cluster', 'men cluster', and 'menu nutrition service cluster' after conducting a cluster analysis with influencing variables affecting patients meal satisfaction. The overview results of patient satisfaction by cluster were : in the case of the service group, such factors as taste, portion size, dealing with complaints while dining meal rounding while dining should be managed with caution In case of the nutrition management group, such factors as taste, portion size, temperature of the food intake, and dependence on hospital food should be managed with care, In the case of the menu groups, such factors as punctuality of meal times, contaminated substances in meals and serving mistakes, cleanliness of dishes, kindness of the server meal rounding while dining should by particularly managed with importance.