• 설비공학논문집
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• 제2권3호
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• pp.166-176
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• 1990

Experimental study was made to find the effective ways for cooling of engine room in a power car through natural ventilation, forced ventilation and wind tunnel test of 1:10 model. Through the measurements of inner temperature of engine room and pressure distribution of model surface for the various opening combinations and the fan locations, the following results are obtained. For natural ventilation, side and top opening combination is more effective than the side openings only and optimal opening combination is all side openings with top center opening. For forced ventilation with fan on the roof, the combination of all sides and top opening is more effective than the combination of side and top opening, and the optimal location of fan is top center. When the model is located in the air stream, the combination of side and top opening is more effective than the side openings only, and the optimal location of top opening is the front opening. With both air stream and forced ventilation, the optimal location of fan is the side region, and the direction of side grill installation is found to have negligible effect on the room ventilation.

• 펄프종이기술
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• 제36권3호
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• pp.60-66
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• 2004

The effects of roll diameter, winding time, winding methods and relative humidity on curl In newsprints(46$g/m^2$, 54 $g/m^2$, and 54 $g/m^2$ SNC) are examined. The larger MD curl appears at smaller roll diameter, with the extension of winding time, and at the treat ment of soft nip calendering. The MD curl shows the back side curl at winding methods with top side as outer side(TSO), and the top side curl with top side as inner side(TSI). While the CD curl in newsprints( 46 $g/m^2$, and 54 $g/m^2$ SNC) treated with calender is hardly influenced by the storage times, roll diameter, and winding methods. However the CD curl in newsprint(54 $g/m^2$) gradually increases to a two weeks, and then hold constant regardless of roll diameter and winding methods.. The CD curl shows always the top side curl regardless of winding methods. At high relative humidity, the CD curl largely reduces, but the MD curl is not nearly changed. Especially, the CD curl in news-prints(54 $g/m^2$ SNC) is little affected by the changes of relative humidity.

• 대한지역사회영양학회지
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• 제13권3호
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• pp.346-358
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• 2008

The purpose of this study is to find differences in dietary patterns through menu analysis by economic status. The data was obtained from the 1998 and 2001 National Health and Nutrition Survey of Korea. The main variables were economic status, sex, and area by urbanization. The economic status was classified into low, middle, high, and top classes using a poverty line based on the 1998 and 2001 minimum standard cost of living. The areas were divided into metropolis, small city, and rural areas. The dishes of 3 meals were classified into 29 categories by cooking method. The most frequent pattern was "rice + soup + kimchi". The frequency of this Korean basic dietary pattern was the lowest in the top income class and metropolis areas, while the highest in the low income class and rural areas. The frequency of Korean recommended dietary pattern, that is, "rice + soup or stew + kimchi + side dish" was the highest in the top income class. The metropolis group preferred side dishes using meat and a cooking method that saved time, but the rural group preferred side dishes using vegetables and cooking methods that take a longer time. In comparison of dietary pattern between male and female by economic status, the higher economic status, the male's dietary patterns showed more side dishes than those of female. But the main side dish was kimchi in male low class. Consequently, the major dietary pattern in Korea is rice-style, though the western pattern is increasing in the top income class, especially in metropolis areas. Therefore, to make a better dietary pattern, we should develop and spread low-priced recipes of various side dishes and teach financial skills such as ability to make a food budget for lower income classes. Also, we should emphasize the importance of the balance between meat and vegetables and traditional diet and western diet for the top income class, especially in the metropolis areas.

• 한국항해항만학회지
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• 제35권2호
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• pp.113-119
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• 2011

This paper is a part of the development on the safe navigation model of tugs and barges in Korea waters. desk-top tug-barge simulator is to train the crew of tugs and barges, especially tugs' crew. It is connected with steering and engine telegraph console and winch control console, and can describe three types of operation mode for a tug-barge working unit, towing mode, side by side and push mode. It can also record and assess each simulation run. The evaluation module can confirm the result of a finished simulation run and help trainees to find and correct their faults, and it is composed of result evaluation and process evaluation.

• 대한한의진단학회지
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• 제18권3호
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• pp.217-223
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• 2014

Objectives This study is on the implementation of the electric cauterizer with the hole for acupuncture to achieve the superposition effect of acupuncture-moxibustion therapies. Methods In this paper, we especially made a hole across the heat terminal of the electric cauterizer for acupuncture. Before the cauterization, the doctor treats a patient with needle. And after acupuncture, the heat terminal is to be superposed upon the needle along the hole to add the cauterization. Results There are 2 coupling methods that the heat terminal is to be superposed with the needle; one is the top-coupling and the other is side-coupling. The top-coupling means that the heat terminal is to be superposed upon the needle along the top of the needle, and side-coupling means that the heat terminal is to be superposed to the needle along the side of the needle. Conclusion This study was aimed to implement the electric cauterizer with the hole for acupuncture to achieve the superposition effect of acupuncture-moxibustion therapies. Not electric acupuncture but manual acupuncture is adopted. The electric cauterizer generates the heat $38{\sim}45^{\circ}C$. This heat is safe for skin not to burn. The electric cauterizer constitutes the smokeless moxa- pad which effects the skin DDS.

• 한국콘텐츠학회논문지
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• 제9권11호
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• pp.10-17
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• 2009

Wyner-Ziv 비디오 부호화 기술은 Slepian-Wolf와 Wyner-Ziv의 분산 정보원 부호화 (DSC : distributed source coding) 이론을 기반으로 한 새로운 비디오 압축 패러다임이다. Wyner-Ziv 부호화는 기존 부호화기 측의 복잡한 작업을 복호화기 측으로 이동시킴으로써 단순한 부호화기/복잡한 복호화기의 구조를 실현한다. Wyner-Ziv 복호화기는 원영상의 예측신호인 보조정보를 생성하기 위해 움직임 추정 및 보상을 수행하며, Wyner-Ziv 부호화기의 정보량은 이 보조정보에 직접적으로 의존하기 때문에 보조정보 생성효율은 전체 부호화 성능에 큰 영향을 미친다. 본 논문에서는 필드 부호화를 이용한 개선된 보조정보 생성방법을 제안한다. 우선 top 필드는 기존의 방식으로 부호화되고, bottom 필드는 이미 복호화 된 top 필드의 정보를 이용한 새로운 보조정보 생성방식으로 부호화된다. 실험결과를 통해 제안된 보조정보 생성방식이 기존의 방식과 비교할 때, 율-왜곡 성능 및 주관적 화질이 개선되었음을 알 수 있다.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2010년도 정기 학술대회
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• pp.110-113
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• 2010

해양플랜트 구조물은 대양에서 파력을 비롯한 바람 등과 같이 자연에 의해 발생하는 다양한 외력을 구조물 사용기간 동안 지속적으로 랜덤하게 받게 되므로 이로 인한 피로현상이 발생하게 된다. 특히 용접부로 이루어진 격점부는 복잡한 기하형상의 영향으로 피로에 대해 취약구조가 되므로 피로강도향상은 해양플랜트 구조의 안전성에 중요한 요인이 된다. 본 연구에서는 격점부에 대한 구조상세에 관련한 설계기준 및 평가방법을 조사하였으며, 고정식 Jacket 구조물을 대상으로 프레임요소를 사용하여 구조해석을 실시하여 공용하중에 대한 구조거동을 분석하였다. 또한 격점부의 강도평가방법 및 연결부 피로강도를 개선하기 위하여 프레임요소의 구조해석을 토대로 복잡한 기하형상을 가진 KT형 관이음부(Tubular Joints)에 대해 상세해석을 실시하였다.

• Tribology and Lubricants
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• 제35권6호
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• pp.337-342
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• 2019

This paper presents an experimental investigation of friction and wear characteristic with respect to patterns occurring on the surface of 3D printed polymer products by fused deposition modeling method. The purpose of this study was to investigate the effect of the patterns and sliding directions on the tribological properties of 3D printed polymer surface. A cubic specimen was printed using polylactic acid filament as the printing material. Friction tests were conducted for different directions with respect to the patterns that were generated on the top and the side surfaces of the specimen, by using a ball-on-reciprocating type tribotester. SUJ2 bearing ball of which the diameter was 11 times greater than the width of the largest pattern was used as the counter surface to assess the frictional behavior. Friction tests were conducted on the top and the side surfaces with respect to the patterns in 3 (0°, 45°, 90°) different directions respectively. Coefficient of friction increased as cycles increased in all cases. The results of the tests showed that the lowest coefficient of friction was measured with the 45° sliding direction on the side surface. The wear rate was the lowest at 45° sliding direction on the side surface, while it was the highest at 0° sliding direction on the top surface. Coefficient of friction of about 0.45 was determined to be the converging value on the top compared to the side surface.

• 한국지반환경공학회 논문집
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• 제5권4호
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• pp.73-79
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• 2004

도로주변 절토사면 상부에 설치되는 산마루측구는 강우시 상부로부터 흘러내려오는 지표수를 원활히 배수시켜, 절토면으로 유입되는 것을 방지하기 위해 설치한다. 그러나, 산마루측구 설치시 시공여건상 품질관리가 어려워, 절토면 배면으로부터의 지표수를 원활히 배수시키지 못하는 문제점을 안고 있다. 따라서, 본 논문에서는 비탈면 상부에 설치된 산마루측구의 기능을 지반 및 지형조건, 강우조건에 따라 비탈면 안정성에 미치는 영향을 평가함으로써, 현재 설계 시공되고 있는 산마루측구의 설치 적정성을 평가하였다. 평가결과 산마루측구는 평균적으로 강우시 약 3%의 안전율 증대효과가 있는 것으로 검토되었다.

• 한국정밀공학회지
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• 제26권2호
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• pp.86-93
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• 2009

Elastomeric O-rings have been the most common seals due to their excellent sealing capacity, and availability in costs and sizes. One of the critical applications of O-ring seals is solid rocket motor joint seal where the operating hot gas must be sealed during the combustion. This has long been a design issue to avoid the system failure. For laterally constrained, squeezed and pressurized condition, deformed shape of O-ring was measured by computed tomography method and CCD laser sensor, compared with numerical calculations. As clearance gap changes, sealing performance had been evaluated on peak contact stresses at top, bottom and side contact surfaces. As clearance gap increases, peak contact stresses and contact widths in top and side contact surfaces increase, and the asymmetry of stress distributions is promoted due to pressure increase. It is suggested that peak stress of bottom contact surface can be approximated by simple superposition of peak ones due to squeeze and pressure. Under pressurized condition, sealing performance is dependent on not peak stresses of bottom and side contact surfaces but that of top.