• 대한기계학회논문집B
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• 제32권12호
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• pp.907-914
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• 2008

This study is mainly focused on the assessment of return, semi return, and returnless fuel supply system for an LPi engine. In order to compare the return type with returnless one with various LPG blends, combustion analysis and cyclic THC emission characteristic were tested at the part load operating condition of the LPi engine. Considering heat balance of each fuel supply systems, pressure and temperature increment of return type showed lower at the fuel rail during idle warm up operation. However, those of returnless type at LPG tank maintained stable and slow increment because the heat transfer from the LPi engine was minimized. Finally, hot restartability of each fuel supply systems were evaluated with the various LPG blends and fuel temperatures. As a result, semi return type has equivalent performance to return type considering combustion and emission characteristic, hot restartability performance for LPi engine.

• 정보관리학회지
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• 제21권2호
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• pp.169-187
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• 2004

미래 도서관의 패러다임이 정보소장에서 정보접근으로 변화됨에 따라 도서관상호협력과 문헌제공서비스의 중요성이 증가하고 있다. 이를 위하여 개별 도서관들은 자료의 구입예산을 절감하고 도서관정보서비스의 질적인 향상을 물론 이용자의 정보서비스에 대한 만족도를 제고한다는 점에서 문헌제공서비스의 활용은 상당한 장점이 있다. 본 연구는 문헌제공서비스의 효과적인 수행과 이용을 위한 국내 이용자들의 문헌제공서비스 트랜잭션 데이터 분석을 통하여 문헌제공서비스의 이용추이와 동향을 예측하고, 여기에 나타난 그들의 요구변화를 검토하여 국내 도서관 및 정보센터의 문헌제공서비스의 질적인 향상과 이용자 만족도 제고에 사용할 수 있는 근거 자료를 제시하는데 그 목적이 있다. 이를 위하여 KISTI-DDS의 실제 이용데이터를 활용하여 문헌제공서비스의 연도별, 지역별, 이용계층별 차이를 분석하였으며, 자료유형별 복사추이도 관찰하였다. 또한 이용자들이 원문복사를 제공하는 복사 제공기관과 원문입수방법을 검토하고 연도별, 이용계층별로 의미있는 차이가 있는지를 분석하였다.

• 한국식품영양학회지
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• 제34권4호
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• pp.365-371
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• 2021

This study was conducted to understand the type of use and satisfaction of delivery food by Chinese and Korean students. In December 2019, Korean and Chinese students living in Gyeonggi Province were analyzed using SPSS. The average number of food deliveries was 1~2 times a month and used 30.7% of the Korean students and 21.8% of the Chinese students. As for how to order food for delivery, 62.2% of Korean college students took up mobile apps, and 49.0% of Chinese students took up mobile phones. In terms of satisfaction after using delivery food, Korean students scored 3.89 points for taste and 3.74 points for using a neat and convenient packaging container, while Chinese students showed the highest score of 3.69 points for past eating experiences and 3.65 points for taste. As for the factors influencing the satisfaction after using the delivered food, the food quality satisfaction (β=0.518) for Korean students and favorable menu factor (β=0.533) for Chinese students were found. Therefore, it is judged that it is necessary to continuously improve the quality, service, convenience and diversity of delivered food, and health and safety factors in order to improve the delivery patterns and satisfaction of college students.

• 한국디지털건축인테리어학회논문집
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• 제12권3호
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• pp.15-25
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• 2012

The purpose of this research is to explore the necessity of utilizing IPD methods along BIM based project operation in domestic construction market. IPD is relatively new project delivery methods focused on the collaboration of stockholders based on BIM technology. IPD is focused on the multiparty contract process rather than multiple bilateral contracts under Traditional Project Delivery Methods. The research method is to investigate the IPD standard contract documents, successful IPD project cases in the U.S. The research results are as follows. The model for an IPD standard contract needs to be developed for the application to a real construction projects. Various types of IPD model contract need to be developed to accommodate the requirements of industry and stockholders in Korea.

• 대한의용생체공학회:의공학회지
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• 제18권2호
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• pp.173-178
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• 1997

pH sensitive polymers have long been utilized as one important type among many interesting drug delivery systems. This is due to the reason of different pH environments in human organs, which requires different pH control mechanism depending upon the organs. In the present study the pH sensitivity was investigated for both pH sensitive and pH insensitive biopolymers using the diffusion effect along with the swelling effect. NMR microscopy was performed along with optical microscopy. For the analysis of diffusion effect, UMR Microscopy was perFormed to measure diffusion coefficients for various liquids such as distilled water, acetone and DMSO(dimethyl sulfoxide). Also, this technique is expected to contribute to the studies for many pH drug delivery systems.

• 한국건축시공학회지
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• 제9권5호
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• pp.111-117
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• 2009

건설공사는 복잡화, 다양화, 대형화 되고 있으며 이러한 다변화된 건설 환경에 대응하기 위해 건설 선진국에서는 다양한 발주방식을 도입 적용해 오고 있다. 국내에서도 지속적으로 발주제도를 개선해 오고 있으며, 최근에는 공공건설공사의 발주방식을 보다 다양화하려는 취지에서 국가계약법시행령 개정을 통해 "기술제안입찰", "설계공모 기술제안입찰"을 새로 도입하였다. 이러한 정부의 노력에 부합되도록 공공공사에 적절한 발주방식선정기준이 제시되어야 한다. 이에 본 연구에서는 기 발주된 건설 공사 실태 및 현황분석을 설문조사를 통하여 문제점을 정리하였고, 이 문제점에 대한 개선방안으로 사업유형별 발주방식 선정기준을 제시하였다.

• 한국자동차공학회논문집
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• 제9권1호
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• pp.94-101
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• 2001

In this paper, the combustion improvement effects of alcohol-diesel oil blend fuel were investigated in a visualization engine. As a result of experiment, it was found out that the combustion chamber of deep dish type and re-entrant type at the same operation condition. However, when the con-tent of alcohol exceeded 10% of total fuel delivery, the combustion of alcohol-diesel oil blend fuel was worse than that of diesel oil. The maximum blend quantity of ethanol which is not ignited in the re-entrant type combustion chamber was estimated at approximately 40% of total fuel delivery. So, it is necessary to blend appropriate quantity of a volatility fuel such as alcohol in order to improve combustion.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2005년도 춘계학술대회 논문집
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• pp.1087-1090
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• 2005

In precision machinery systems for medical and chemical applications, micropumps with a low pulsation have been demanded and investigated for accurate delivery of a small amount of liquid. This study proposes sheet type check valves instead of ball type check valves for PZT pumps and performs some tests on dynamics characteristics of check valves having different design parameter with variable frequency. The selected materials of check valves is NBR, PP film, Polyimide and Stainless steel(SUS304). In the experiment, dynamic characteristics of stainless steel thin plate have better performance than others.

• Journal of Pharmaceutical Investigation
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• 제36권2호
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• pp.97-102
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• 2006

The aim of this study was to investigate the feasibility and optimize permeability of slim patch type as a transdermal delivery system of caffein. Slim patch type was formulated and tested in modified Franz diffusion cell across cellulose membrane and hairless mouse skin in pH 5.8 phosphate buffer solution (PBS). The effect of $Pharmsolv^{\circledR}$ and drug concentration on permeation at four model, 1,2% $Pharmsolv^{\circledR}$ with $0.12\;mg/cm^2$ caffein and 0.12, $1.2\;mg/cm^2$ caffein with 2% $Pharmsolv^{\circledR}$ through hairless mouse skin was studied in vitro. The release of caffein from slim patch with various loading was fitted by the Higuchi's diffusion equation. The result showed that chemical $Pharmsolv^{\circledR}$ produced a large and significant increase of permeation. The effect of 2% $Pharmsolv^{\circledR}$ on permeation of caffein was greater about 10-fold greater than 1% $Pharmsolv^{\circledR}$ in first 60 minutes. The effect of drug concentration, however, was lower than that produced by chemical $Pharmsolv^{\circledR}$. Within the tested system, the most efficient combination for caffein slim patch type was $0.12\;mg/cm^2$ caffein with 2% $Pharmsolv^{\circledR},$ although $1.2\;mg/cm^2$ caffein with 2% $Pharmsolv^{\circledR}$ showed highest amounts permeation, because permeated percentages were significantly lower about $1/4{\sim}1/5$ times.

• 한국항해항만학회지
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• 제29권3호
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• pp.221-226
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• 2005

본 연구는 화물 운송 문제에 GIS 기법을 응용하여 화물의 수거 및 배송문제를 개선한 논문이다. 최근 국내 물류업체들은 인터넷을 기반으로 주문, 검색 및 화물의 추적 등을 온라인상에서 실행토록 하는 방법을 중시하게 되었다. 국내외 배송 관련 기업들은 빠른 서비스를 요 구하는 긴급주문의 비중이 커 가는 시장변환에 대처해서, 서비스 능력의 향상과 효율적인 차량관리를 위해서 GPS와 TRS 등의 정보통신기술을 이용하여, 기업의 배차업무를 개선하려고 노력하고 있다. 하지만 아직까지 배차 담당자의 의사결정을 지원할 수 있는 배차기법에 대한 연구는 거의 이루어지지 않고 있는 것이 현 실정이다, 본 연구에서는 GIS기반 하에서의 거리산정방법을 제안하고 이를 이용하여 차량운송 및 수거계획 알고리즘을 개발하였다. 또한 본 연구에서는 차량 및 화물정보를 GIS환경에서 실시간으로 조회해 볼 수 있도록 하였으며, 입출력자료와 차량 및 화물정보 조회결과를 GIS환경에서 구현하도록 하였다. 사용자들을 위하여 GUI-type 프로그램을 개발하고 실 예제를 통하여 Sample 출력을 보였다. 본 연구의 결과는 추후 약간의 수정 보완을 통하여 실제 물류센터에서의 운송계획 작성시 바로 적용할 수 있을 것이라고 판단된다.