• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2017년도 춘계 학술논문 발표대회
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• pp.56-57
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• 2017

In recent years, new construction methods have been required to reduce the construction cost and increase the available area in an environment where construction work is frequently performed in a narrow urban area like Korea. As a result of these studies, slim floor composite beam has been suggested. Slim floor composite beam can reduce required depth because web of steel beam is embedded in the slab, so it is effective to reduce floor height and increase the available area. The purpose of this study is the floor height reduction evaluation by comparing system consisting of reinforced concrete, steel, and slim floor using square-shape steel pipe. After doing structural design for a typical plan, checked effectiveness by comparing each design plan. It is proven that slim floor composite beam can reduce required depth effectively comparing required materials of other system.

• 유체기계공업학회:학술대회논문집
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• 유체기계공업학회 2003년도 유체기계 연구개발 발표회 논문집
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• pp.627-630
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• 2003

This work presents a numerical procedure to optimize the shape of three-dimensional channel with angled ribs mounted on one of the walls to enhance turbulent heat transfer. The response surface method is used as an optimization technique with Reynolds-averaged Navier-Stokes analysis of flow and heat transfer. SST turbulence model is used as a turbulence closure. The width-to-height ratio of the rib, rib height-to-channel height ratio, pitch-to-rib height ratio and attack angle of the rib are chosen as design variables. The objective function is defined as a linear combination of heat-transfer and friction-loss related terms with weighting factor. D-optimal experimental design method is used to determine the data points. Optimum shapes of the channel have been obtained for the weighting factors in the range from 0.0 to 1.0.

• 아시안잔디학회지
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• 제18권1호
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• pp.37-46
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• 2004

본 연구는 골프코스관리자들이 빠른 그린관리를 위한 장비 사용 계획시 참고가 될 수 있는 기초자료를 제공하고자 그린모아 유형(보행식, 승용식)에 따른 그린스피드 차이, 보행식 그린모아에 장착된 회전날 유형(9날, 11날)에 따른 그린스피드 차이 그리고 롤러 유형(승용식 그린정리기, 경량롤러)에 따른 그린스피드 차이를 비교하였다. 그 결과의 요약은 다음과 같았다. 1. 그린모아 유형(보행식, 승용식)에 따른 그린스피드 차이는 깎기 후 바로 그리고 깎기 후 8시간 경과 뒤에도 보행식 그린모아를 사용한 3.8mm 깎기 처리구가 승용식 그린긴아를 사용한 3.8mm 깎기 처리구에 비해 그린스피드가 빠르게 나타났고 이는 95% 유의수준에서 통계적으로 유의한 결과였다. 따라서 보행식 그린모아가 승용식 그린모아에 비해 빠른 그린 관리에 적합한 장비 유형으로 판단되 었다. 2. 그린모아에 장착된 회전날 유형(9날, 11날)에 따른 그린스피드 차이는 11날 장착 보행식 그린모아를 사용한 3.2mrn 깎기 처리구가 9날 장착 보행식 그린모아를 사용한 3.2mm 깎기 처리구에 비해 그린스피드가 빠르게 나타났고 이는 95% 유의수준에서 통계적으로 유의한 결과였다. 따라서, 11날이 9날보다 빠른 그린관리에 적합한 회전날 유형으로 판단되었다. 3. 보행식 그린모아로 3.0mm로 깎기한 다음이어서 승용식 그린정리기로 1회 롤링한 처리구와 보행식 그린모아로 3.0mm로 깎기한 다음 이어서 경량롤러로 1회 롤링한 처리구간의 그린스피드 차이(다짐후 그린스피드 증가효과)는 95% 유의수준에서 통계적으로 유의하지 못했으나 8시간 경과 뒤에 측정한 두 처리구들의 그린스피드의 차이(다짐후 그린스피드 감소효과)는 95% 유의수준에서 통계적으로 유의한 결과를 나타냈다. 따라서, 경량롤러가 승용식 그린정리기 보다 빠른 그린관리에 적합한 롤러유형으로 판단되었다.

• 한국초전도저온공학회:학술대회논문집
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• 한국초전도저온공학회 2002년도 학술대회 논문집
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• pp.31-34
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• 2002

In this study, thermal analysis of a thermal capacitor, which is used to cool the current lead in conduction-cooled superconducting systems, was done. The temperature difference across a thermal capacitor was calculated by using heat conduction equation. Effect of heat load, total thickness, height and length of a thermal capacitor on the temperature difference were show. Using the results in this work, total thickness and heat height of a thermal capacitor can be determined for given heat load and given temperature difference. This work can be used practically in design for every superconduction system using a current lead.

• The Journal of Korean Physical Therapy
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• 제18권6호
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• pp.67-75
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• 2006

Purpose: Many kinds of musculoskeletal disease and symptom are caused by the longtime computer works. However, trapezius muscle tonus has not been established in regarding to keyboard height during typing. Therefore, this study is to evaluate the relationship between trapezius muscle tonus and the height of keyboard while typing, controling for the postures of neck, Lumbar, cervical vertebra. Methods: The experimental height of keyboard was set at elbow height, 3cm higher, 6cm higher, 9cm higher, than elbow. We studied trapezius tonus with the mean value for 2 minutes by EMG in 15 males and 15 females worker of hospital in seoul, who did not have a history of muscle disease, neurological signs, nerve damage. Results: In this experimental, as the height of the keyboard went up, the trapezius tonus significantly increased with shoulder abduction of brachium. Second, right and left trapezius tonus appeared similar while typing. Third, the best height that release the trapezius tonus the was as high as elbow and 3cm higher than elbow. Conclusion: With these above results, we suggest that the appropriate height of keyboard during typing to release the trapezius tonus most is the height of the elbow and 3cm higher than elbow. The study has important implications for focusing on the height of VDT worktable and complaining of a pain by oneself which are useful to establish a method of prevention of musculoskeletal disorder in work in the future.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1995년도 추계학술대회 논문집
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• pp.210-213
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• 1995

In this study,the effect of both process parameters (wheel velocity, friction coefficients between die and billet, etc) and die-shape (abutment height and shape, flash gap, etc.) on the surface defect on forming process is theoretically investigated. For this work, computer simulation was performed by using the DEFORM, a commercial FEM code. Through numerous simulations with different parameters and die shapes, We propose one optimal die shape for CONFORM process which can remove surface defect.

• 대한인간공학회지
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• 제17권3호
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• pp.91-101
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• 1998

Anthropometric characteristics and considerations of sex differences are essential for the correct design of ergonomic work spaces. This paper is concerned with longitudinal study on the physical growth in the Korean youth. Five hundred and fourty subjects were selected from third year students of high schools, and their records on physical examination during the last twelve years were surveyed by longitudinal method. This study investigated the anthropometric characteristics of physical structure and the shape of physical growth for boys and girls. The result showed that there were significant sex differences in the pattern of physical growth in height.

• 한국안전학회지
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• 제29권5호
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• pp.29-34
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• 2014

The live line working is inherently dangerous as the workers have to work under the risk of electrical shock and most of works are carried out at height. The live line working need the some specific techniques and higher level safety measures such as a risk assessment to carry out works safely, but the electrical construction companies performed live-line working are usually small-sized companies. They have less capacity to have own safety management system. This study intended to conduct an in-depth analysis on the cause of electric shock accidents to provide basic data for policy proposing taking into considering the past eleven years for a long-term plan. And the aim of this study is to propose the policy about the equipment performance standards and/or worker's safety standards to revise the standards for preventing electric shock accidents, moreover, co-relation of the electrical work order form and on safety workings, especially electrical construction company/work.

• 한국안전학회지
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• 제24권2호
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• pp.89-93
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• 2009

The muscular-skeletal disorders that have become a major issue recently in Korean industrial safety area are mainly caused by manual material handling task. The objective of this study is to provide scientific data for the establishment of work safety standard for Korean workers through the experiments of lifting task under various conditions, in order to prevent the muscular-skeletal disorders in the industrial work site. This study used the psychophysical approach to determine the maximum acceptable weight(MAWL) for seven young male subjects, and used isometric and isoinertial strength variables as predictors to develop prediction models. Also, the oxygen consumption, heart rate, and RPE were measured or recorded while subjects were lifting their MAWL. Three different lifting frequencies(1, 3, 5lifts/min) with two lifting range from floor to knuckle height and knuckle to shoulder height for one hour's work shift using free style lifting technique were studied. These results may not only provide scientific data in establishing the safety standards for Korean workers' lifting tasks, but also contribute preventing the rapidly increasing muscular-skeletal disorders lately on the industrial site.

• 대한인간공학회지
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• 제25권2호
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• pp.11-22
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• 2006

The muscular-skeletal disorders(MSDs) that have become a major issue recently in Korean industrial safety area are mainly caused by manual material handling task. The objective of this study is to provide scientific data for the establishment of work safety standard for Korean workers through the experiments of lifting task under various conditions, in order to prevent the muscular-skeletal disorders in the industrial work site. Eight male college students were recruited as participants. Three different lifting frequencies(1, 3, 5 lifts/min) and three twisting angles(including the sagittal plane and two asymmetric angles; i.e., 0°, 45°, 90°) for symmetric and asymmetric tasks, respectively, with three lifting range from floor to knuckle height, knuckle to shoulder, floor to shoulder height for one hour's work shift using free style lifting technique were studied. The maximum acceptable weight of load(MAWL) was determined under the different task conditions, and the oxygen consumption, heart rate, and RPE were measured or recorded while subjects were lifting their MAWLs. The results showed that: (1) The MAWLs were significantly decreased as the task frequency and task angle increased.; (2) The heart rate, oxygen consumption, RPE significantly increased with an increase in lifting frequency although maximum acceptable weight of lift decreased.; (3) The highest heart rate and oxygen consumption was recorded at the lifting range of floor to shoulder, followed by floor to knuckle and knuckle to shoulder.; (4) The RPE value showed that subjects perceived more exertion at the high frequency rate of lifting task and lifting range of floor to shoulder height. (5) The modeling for MAWL using isometric strength, task angle and lifting frequency were developed. It is expected that use of the results provided in this study may prove helpful in reducing MMH hazards, especially from lifting tasks for Korean, and can be used as a basis for pre-employment screening.