• 제목/요약/키워드: bench

검색결과 1,097건 처리시간 0.019초

지구관측위성의 블레이드형 광학탑재체 지지구조물 설계 (Design of the Blade-Type Optical Bench for Earth Observation Satellite)

  • 김경원;김진희;이주훈;진익민;김종우;박종성
    • 한국항공우주학회지
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    • 제33권11호
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    • pp.88-94
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    • 2005
  • 본 논문은 강성 요구조건과 열지향오차 요구조건을 만족하는 지구관측위성의 블레이드형 광학탑재체 지지구조물 개발에 대한 연구이다. 먼저 형상 요구조건을 만족하는 광학탑재체 지지구조물을 설계하였으나, 강성 요구조건을 만족하지 못하여 광학탑재체 지지구조물의 외부와 내부에 보강재를 추가하여 이를 해결하였다. 그러나, 열지향오차 요구조건을 만족시키지 못하여, 플랫폼 지지 구조물을 플래폼 상/하단에 모두 장착한 대칭형 구조로 설계하였다. 이 경우 이전 모델에 비해서 열지향오차가 많이 줄어들기는 하였지만 역시 열지향오차 요구조건을 만족시키지는 못하였다. 이전 설계 결과를 바탕으로 측면형 플랫폼 지지 구조물을 설계하여 강성요구조건 및 열지향오차 요구조건을 만족하는 광학탑재체 지지구조물을 최종적으로 설계하였다. 본 설계를 통해서 다음의 결론을 얻을 수 있었다. 강성측면에서는 플랫폼의 면재 두께 증가나 보강재 추가 그리고 블레이드의 개수를 늘려서 강성을 증가시킬 수 있었다. 열지향오차측면에서는 가능한 같은 재료를 가진 구성품들을 서로 결합시키고, 광학탑재체 지지구조물을 대칭형 구조물로 설계함으로써 열지향오차를 감소시킬 수 있었다.

공간개념을 적용한 벤치디자인 개발 연구 (A Study on Bench Design Applied the Concept of Space)

  • 정명택;윤여항
    • 한국가구학회지
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    • 제23권1호
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    • pp.75-83
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    • 2012
  • Space dominates all the art activities human do and plays a role of providing aesthetic emotion. Architecture, sculpture, painting, and furniture, etc. these two and three dimensional works are represented in space and interpreted the role of its form, structure and function. Each area is different, but space has been studied in philosophy, physics, geometry, and mathematical studies, etc. and has been consistently interpreted and represented relating to a variety of human creative activity. Furniture is also three dimensional art being dependent on space. In the United States in 2004, I made the living room bench by applying the spatial concept at Rochester Institute of Technology. Two years later, this design was adopted by wendell Castle Collection, an American furniture company, then prototype were made and tested three times during a year, and then since 2007 as indoor benches it has been manufactured in the United States. The study's purpose is to order the process of its development based on the experience of bench production applied the spatial concept, and by analyzing the properties of spatial concept, I am planning to propose a new concept on interaction with the space and furniture for next.

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관개용수로의 비용분석에 관한 연구 (Cost Comparisou of Conveyance Systems for Irrigation Districts)

  • 최창훈;고재군;박승우;이신호
    • 한국농공학회지
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    • 제27권4호
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    • pp.31-41
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    • 1985
  • This paper compares the estimated total construction and maintenance costs for irrigation canals in six irrigation districts near Pyongtaek. Three conventional canal types were considered: concrete bench flumes, concrete-lined canals, and earth canals. The total expenses for each type were grouped to four catagories: the net construction, land acquisition, maintenance, and other expenses. The construction costs included the assumed costs for conveyance losses from each type of canals. The results from this study support earlier studies that the bench flumes are economically feasible. Initially cheaper conveyance systems like concrete-lined and earth canals demand 'higher maintenance costs and thus, their total expenses are summed to exceed those for the bench flumes within a few years following the construction. Banch flumes are economically justifiable for the main canals of the studying districts. Sensitivity analyses were executed to evaluate the relative importance of each expense to the total cost. The analyses show that total expenses very significantly with the change of the following costs: cost for conveyance losses, net construction, maintenance, and land acquisition, in that order However, other expenses contribute little if not at all to the total. The results indicate that bench flumes should be adopted as main canal structures for most irrigation districts in the Republic.

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벤치발파에서 파쇄도 예측을 위한 암반조건 분석 (Analysis of In-situ Rock Conditions for Fragmentation Prediction in Bench Blasting)

  • 최용근;이정인;이정상;김장순
    • 터널과지하공간
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    • 제14권5호
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    • pp.353-362
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    • 2004
  • 벤치발파에서 암석 파쇄도 예측은 생산계획을 수립하는 데 있어서 가장 중요한 요소 중의 하나이다. Kua-Ram 모델은 지금까지 제안된 암석 파쇄도 예측 모델 중 가장 우수한 것으로 평가받고 있으나, 이 모델의 평가항목을 구성하고 있는 절리조건, 암석강도, 밀도, 사용폭약의 성능과 저항선, 공간격 등의 요소들은 그 값을 선정하는 과정에서 주관적인 요소가 개입되거나 정의가 모호한 요소를 포함하고 있다. 이 연구에서는 Kuz-Ram 모델을 구성하는 여러 평가항목의 값을 선정하는 과정에서 주관적이거나 모호한 요소를 제거하는 방법에 대해 검토하였으며, 예측값을 현장조사 결과와 비교하여 적용성을 검토하였다. Kuz-Ram 모델은 비교적 정확한 예측결과를 보였으나, 현지암반 조건을 충분히 반영하지 못하여 개선이 필요한 것으로 판단되었다.

SI 열화학싸이클 황산분해공정의 Bench-scale 상압 실험 (Bench-scale Test of Sulfuric Acid Decomposition Process in SI Thermochemical Cycle at Ambient Pressure)

  • 전동근;이기용;김홍곤;김창수
    • 한국수소및신에너지학회논문집
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    • 제22권2호
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    • pp.139-151
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    • 2011
  • The sulfur-iodine (SI) thermochemical water splitting cycle is one of promising hydrogen production methods from water using high-temperature heat generated from a high temperature gas-cooled nuclear reactor (HTGR). The SI cycle consists of three main units, such as Bunsen reaction, HI decomposition, and $H_2SO_4$ decomposition. The feasibility of continuous operation of a series of subunits for $H_2SO_4$ decomposition was investigated with a bench-scale facility working at ambient pressure. It showed stable and reproducible $H_2SO_4$ decomposition by steadily producing $SO_2$ and $O_2$ corresponding to a capacity of 1 mol/h $H_2$ for 24 hrs.

지하철 승강장 벤치 디자인 유형의 개선방안에 관한 연구 (A Study on the Improvement Plan of Bench Design at a Subway Platform)

  • 양혜원;김준지;이주현;이현수
    • KIEAE Journal
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    • 제8권2호
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    • pp.71-78
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    • 2008
  • Subway is a major transportation in the city that is allied to the daily life of people. As a public space, subway station must satisfy the citizens with convenience, safety and esthetic factors. The bench which is one of the major street furniture on the subway platform has a lot of physical contact. Therefore the design of benches must be considered in the aspects of not only aesthetic design but also ergonomic design. The goal of this study is to find out the current conditions and problems of benches and at the same time suggest how to arrange, design, and manage them at the proper manners at subway platform. The result of the study is as follows. First, the problems of design are that the benches at a same platform have various design, the saturation of color is too high, and the design is unfashionable. The second, at the management part there is no such a total management system and specialist for the street furniture section and lack of rational management regulations. The third, results of a new survey suggest that citizens think negatively about present bench's conditions such as design and administration.

정상유동 장치에서 유동 특성 평가 방법에 대한 연구(2) - ISM와 PIV 측정의 비교 (Study on Evaluation Method of Flow Characteristics in Steady Flow Bench(2) - Comparison of ISM and PIV Measurement)

  • 박찬준;엄인용
    • 한국자동차공학회논문집
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    • 제23권1호
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    • pp.139-147
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    • 2015
  • This paper is the second investigation on the evaluation methods of flow characteristics in a steady flow bench. In the previous work, several assumptions used in the steady flow bench were examined and it was concluded that the assumption of the solid rotation might cause serious problems. In this study, intake valve angle is selected as a main parameter for the assessment because the main flow direction to cylinder governed by this angle has the strongest influence on the in-cylinder flow pattern. For this purpose, four heads, which have the different angle, are prepared and the flow characteristics are estimated both by the conventional impulse swirl meter and a particle image velocimetry at 1.75 times bore position apart from the cylinder head, which is widely used plane in the steady flow measurement. The results show that both of the eccentricity and the velocity profile distort the flow characteristics when using the ISM at 1.75 plane, however, the effects of two factors act in the opposite direction. In addition, the profile's influence is much greater than that of the eccentricity.

벤치 프레스 운동 시 하중에 따른 어깨가슴관절의 움직임이 어깨복합체 근 활성도에 미치는 영향 (Effect of Scapulothoracic Joint Movement and Resistance Training Intensity on Shoulder Complex Muscle Activation during Bench Press Exercise)

  • 김윤환;이기광;이만기
    • 한국운동역학회지
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    • 제23권2호
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    • pp.141-148
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    • 2013
  • The purpose of this study was to investigate the scapulothoracic joint movement between different weight bearing contributing to effective bench press exercise. Ten male subjects participated in this study. All subjects were tested on the flat bench press machine which modified weight (50% and 70% of 1RM) and subjects were performed two different conditions(none protraction condition and protraction condition). Weight bar height and vertical velocity, EMG activation was measured using 3D motion capture system and wireless EMG analysis system. As the results, none protraction condition showed that it is more concentrate better pectoralis major muscle activation than protraction condition and middle pectoralis major, anterior deltoid and triceps brachii was significant higher integrated EMG in 70% of 1RM condition. In conclusion, limited scapulothoracic joint movement was more effective activated pectoralis major muscle all the weight through, while we could not find that it was not affected integrated EMG on eight muslces related to shoulder complex between scapulothracic joint movement conditions.

Changes in Total Work, Total Work Ratio, Heart Rate, and Blood Lactate during 75% 1-RM Bench Press Exercise

  • Kim, Ki Hong;Kim, Byung Kwan
    • Medical Lasers
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    • 제10권3호
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    • pp.153-160
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    • 2021
  • Background and Objectives This study was conducted to investigate the change of total work and total work ratio for each set, peak heart rate during exercise, and blood lactate for each set during the 5-set bench press exercise at 75% one repetition maximum test (1-RM). Materials and Methods Seven men in their 20s with more than 6 months of experience doing resistance exercises were selected as subjects, and their 1-RM bench press was measured two weeks before the experiment and 75% 1-RM was measured one week before the experiment. In this study, total work was measured for each set, and heart rate was measured during rest and set-by-set exercise. Blood lactate was measured during rest time after each set. The raw data were analyzed by repeated one-way ANOVA. Results Total work and total work ratio decreased from 1 set to 4 sets (p < .05), p < .001), heart rate increased from stable at the start of exercise (p < .001) and decreased between 3 sets and 4 sets (p < .05). Blood lactate increased continuously up to 2 sets (p < .001, p < .01). Conclusion In conclusion, total work and heart rate decreased with muscle fatigue during exercise, and blood lactate continuously increased. The results of this study are expected to be useful references for constructing resistance exercise programs in the future.

네트워크 RTK 측량의 사이트 캘리브레이션 방안에 관한 연구 (A Study on the Site Calibration of Network RTK Surveying)

  • 최한준;이병길;연상호
    • 한국측량학회지
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    • 제31권1호
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    • pp.99-107
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    • 2013
  • 최근 측량장비의 발달 및 사용확대와 더불어 국토지리정보원의 네트워크 RTK 측량 기반조성으로 인하여 네트워크 RTK 측량이 측량산업 전반에 많이 활용되고 있다. 현재 공공측량작업규정에는 네트워크 RTK 측량 성과를 수준측량에 적용하기 위해서는 작업지역에 균등하게 분포한 5점 이상의 수준점을 사용하여 사이트 캘리브레이션을 한다고 되어있다. 그러나 지오이드의 기복에 따라 사이트 캘리브레이션이 가능한 수준점 간의 거리와 필요한 점의 수가 다를 수 있다. 본 연구에서는 이를 검증하기 위해 지오이드 기복이 완만한 인천지역과 지오이드 기복이 큰 태백지역을 대상으로 네트워크 RTK 측량을 수행하고 사이트 캘리브레이션에 사용되는 기준점 간의 거리별, 기준점 개수별로 정확도를 비교하였다. 본 연구의 결과 공공측량 규정에서 정한 수직정밀도(0.1m) 허용범위에 들기 위해서는 네트워크 RTK 측량의 사이트 캘리브레이션에 사용되는 기준점의 수와 점간 거리를 상호보완적으로 적용할 수 있는 공공측량작업규정의 개선이 필요함을 알 수 있었다.