• 한국자동차공학회논문집
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• 제16권6호
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• pp.19-25
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• 2008

Selective Catalytic Reduction is effective in the reduction of NOx emission. This research focused to evaluate the performance of a urea-SCR system and was conducted in two procedures. One is SCR reactor test using model gas in order to provide an optimal injection condition itself. In this step, some parametric study on emission temperature, space velocity, aspect ratio and the formation of urea spray were made by using flow visualization and Computation Fluid Dynamics techniques. The basic simulation results contributed in determining the layout for an actual engine test. The other is an engine performance and emission test. The urea injector was placed at the opposite direction of exhaust gases emitted into an exhaust duct and an optimal amount of a reducing agent is estimated accurately under different engine loads and speeds. Furthermore, the variation of NOx emission and applied amount of urea was investigated in terms of modes under the condition of with and without SCR, and other emissions such as PM, CO and NMHC were evaluated quantitatively as well. This research may provide fundamental data for the practical use of urea-SCR in future.

• 한국유체기계학회 논문집
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• 제12권6호
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• pp.41-46
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• 2009

This paper deals with the operating-speed (high-speed) balancing of a refinery gasoline HDS (hydrodesulfurization) process recycle-gas 8-stages compressor rotor. A low-speed balancing condition of the rotor was measured as maintaining the G2.5 level. But an inspection run of operating-speed balancing condition, using tilting-pad journal bearings of actual use, showed that while it could be continuously-operated safely at a rated speed of 10,500 rpm, the rotor would not be able to run over 11,000 rpm as the vibration increased very sharply, approaching 11,000 rpm. In order to cure that a series of operating-speed balancing, which first calculated balance correction-weights by applying the influence coefficient measured and calculated at 10,500 rpm and then implemented correction works, was carried-out. The final operating-speed balancing results showed that the vibrations at the bearing pedestals represented very good levels of 0.2 mm/s by decreasing to as much as the 1/10 of the original vibrations and particularly, even at a targeted maximum continuous operating speed, MCS, of 11,500 rpm the vibrations represented about 1 mm/s, which is the operating-speed balancing vibration specification of API. Therefore, the expansion of MCS was successfully accomplished through the operating-speed balancing.

• 교육시설
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• 제14권3호
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• pp.27-35
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• 2007

The purpose of this research is to analyzing the welfare function of the senior citizen with similar type of compounding the school facility, to analyze the problematical point of present condition. And also propose the spatial constitution which the student and the regional senior citizen are easy to utilize on the basis of the result. In a type of educational facility composition, it became clear that a ratio and the inflection order that elderly welfare facilities occupied of vacant class room were low. In other words, in composition of a school facilities, elderly welfare facilities can be said to be an important problem. As a result of having analyzed an existing compound facilities, there was limited interchange of student and a the aged. In addition, there were problems such as learning environment by an intersection of circulation. Therefore, composition of educational facility and elderly welfare facilities is not space composition that is intersection of simple specification function. In other words, a program of the common space which is necessary for the local community formation is necessary. Setting of semi-public area proposes the function of the existing facility and actual condition of spatial use in prerequisite.

• Tribology and Lubricants
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• 제25권1호
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• pp.43-48
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• 2009

It is reported by many researchers that the textured bearing surfaces, where many tiny micro-pockets or enclosed recesses were incorporated, can enhance the load support and reduce friction force. Recently, the basic lubrication mechanism of micro-pocketed parallel surfaces are explained in terms of "inlet suction" using continuity equation and simply cavitation condition. However, it is required that more actual cavitation condition in the pocket region should be applied to estimate exact bearing performance. In this paper, a commercial computational fluid dynamics (CFD) code, FLUENT is used to investigate the exact lubrication characteristics of infinitely long slider bearing with micro-pockets. The results show that the pressure distributions are highly affected by pocket depths, its positions and numbers. The numerical method adopted in this paper and results can be use in optimal design of textured sliding bearings.

• 한국조경학회지
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• 제23권3호
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• pp.167-176
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• 1995

The purpose of this study is to suggest objective basic data for park management proposal through the quantitative analysis of users' behaviors and satisfaction for the actual conditions of management in Moaksan provincial park. For this, users' behaviors and socio-ecnomic characteristics have been analyzed. Specifically, it attempts to investigate users' anticipation and degree of satisfaction applied Expectancy Theory by Likert scale. And users' satisfaction for the actual conditions of management had been analyzed by using the multiple regression. Results of this study can be summarized as follows ; From the aspect of utilization reality, the male usage was silighty higher than female usage, and the usage rate reality, the male usage was slighty higher than female usage, and the usage rate among the young and students such as university students also appeared slightly higher than the norm. Due to the fact, subject park had been provincial park, bus usage was predominant, and users' visit park 1 or 2 times a year. Generally, the value of users' post occupancy evaluation were higher than those of anticipated, and Use in night and facilities were lower. A sense of the season, dense of forest, beauty of skyline and a perspective view appeared as main explicatory variables having positive effects on the satisfaction level for the landscape. Amount of plant and shade were positive variables on the satisfaction and users' had dissatisfaction with trial damage. According to the multiple regression analysis, the major variables to the satisfaction for the actual condition of vegetation management were diversity, recovery of artificial injury.

• 한국비블리아학회지
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• 제34권1호
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• pp.27-51
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• 2023

이 연구는 사회 환경변화에 따라 충청남도 지역사회 특성에 따른 도서관 이용 및 독서문화진흥을 위한 정책을 마련하는데 있다. 이에 충청남도를 대상으로 도서관 일반 현황, 도서관 및 독서문화 인프라, 법제도 등의 환경분석과 도민(학생, 일반) 대상 도서관 이용 및 독서문화에 관한 실태조사 및 도서관 직원 조사를 실시하였다. 그 결과 분석을 바탕으로 충청남도의 지역사회 특성을 반영하고 그에 따른 정책 방안을 제안하고자 충청남도를 6대 지역생활권역으로 구분하고 도서관 이용 및 독서문화진흥 정책과제 발굴, 충청남도 도서관 직원 대상 의견을 수렴하여 총 20개의 도서관 이용 및 독서문화진흥 정책을 제안하였다. 제안된 정책 추진을 위해서는 지역생활권 도서관의 노력뿐만 아니라 광역대표도서관의 역할과 위상 강화와 함께 충분한 인력과 예산 확보가 뒷받침되어야 한다.

• 한국안전학회지
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• 제27권2호
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• pp.72-77
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• 2012

There are insufficient models that find problems and solutions for accident prevention through risk assessment and suggest safe work process and work instruction from foundation works to finish work for accident decrease. This paper presents a quantitative risk assessment model by analysis of risk factors in each process such as earth works, drainage works, pavement works, appurtenant works and etc based on accident examples and investigation on actual condition in roads construction work. In addition, the safety management system was developed to perform risk assessment of construction and use it for effective safety training for labor.

• 조명전기설비학회논문지
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• 제22권4호
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• pp.153-158
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• 2008

PLC를 사용한 제어 시스템을 설계할 때 여러 종류의 표준언어중 LD언어가 가장 많이 사용되지만, SFC를 사용하면 제어의 흐름을 알기 쉽고 유지보수가 용이하며, 프로그램의 기술성이 뛰어나다. 그러나 SFC 언어는 조건처리시 큰 메모리를 요구한다는 단점이 있다. 따라서 SFC로 설계된 시스템은 자기진단기능을 부가하려면 메모리가 상당히 커야 하고, 속도가 늦은 단점이 있다. 이러한 문제점을 해결하기 위해 본 논문에서는 자기진단 기능을 효율적으로 처리하는 방법을 제시하고, 실례를 통해 타당성을 확인하였다.

• 한국주거학회논문집
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• 제13권6호
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• pp.141-150
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• 2002

The disabled peoples increase in number by disasters from the industrialization and urbanization. The physically handicapped people experience many difficulties in using the facilities in the public buildings. So, this survey proposed the necessary conditions for the handicapped peoples to use without any trouble in public buildings. The objects of investigation were public buildings, village offices, a public library, synthesis hospitals banks, an express bus station, a wedding building, a railroad station etc.. Conclusions were as follow \circled1 The most of buildings were established access road in regulations but parking area was established inappropriately in regulations \circled2 The most of convenience facilities were concentrated on first floor but were established barely in more than second floor. \circled3 The most of convenient facilities were established in appropriately in regulations. \circled4 The other convenient facilities(reception desk, ticket agency, work desk etc.) were not established nearly in the buildings of investigation.

• 한국농촌건축학회논문집
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• 제4권2호
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• pp.1-11
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• 2002

The integrated school has an expectation of the total education environment in which has some problems as regional, emotional, teaching treatment, establishment equipment part because of the based relative establishments are abolished. The expectations are the educating effective rising, the reduce of the responsibility of the teacher, a smooth teacher placing and saving the educating estimate. As the new education course propulsion is raising the school and students discretion and expanding the way of educating, being close to the course of studies, the integrated operation is earnestly needed and such as these versatile background the small schools will keep on getting integrated. So, in this paper I'll object the need and purpose of the integrate operation and show the integrated schools that are now in use. Investigate about actual condition of the integrated school, so after these research I've concluded these things below about the integrated school operating.