• 한국의류학회지
• /
• 제19권6호
• /
• pp.911-923
• /
• 1995

The zone of expansion and contraction of arm surfaces was analyzed, the correlation between arm surface changes was studied, and ergonomic sleeve designs were presented in which the consideration of body surface changes is emphasized. Experiments were carried out which include 43 upper extremity segments, 21 motions and 35 female subjects. The major conclusions of the study are as follows : 1. As a sleeve drafting method, detailed measures should be applied on the base of the sensitivity of body surface changes. The range of arm surface changes can be divided into three zones : concentrated expansion zone, zone of little change, and contraction part. The maximum expansion zone was the upper part of elbow. 2. The correlations were higher in lengths than in circumferences. Arm lengths were mainly correlated with upper arms. The more detailed the arm surface was, the lower the correlations between surface changes were. So there was not a lot of relation between segment changes. Tendency of body surface changes depended on the anatomical structure of the upper extremity and the movements of arm muscles. 3. As an application of measures and ease, ergonomic sleeve designs weve presented in which arm surface changes were considered. Ergonomic sleeve designs are recommended for working clothes and sports wear.

• Earthquakes and Structures
• /
• 제18권4호
• /
• pp.437-449
• /
• 2020

It is quite apparent that engineering concerns related to the influence of masonry infills on seismic behavior of reinforced concrete (RC) structures is likely to remain relevant in the long term, as infill walls maintain their functionalities in construction practice. Within this framework, the present paper mainly deals with the issue in terms of modal expansion of effective earthquake forces and the resultant modal responses. An adequate determination of spatial distribution of effective earthquake forces over the height of the building is highly essential for both seismic analysis and design. The possible influence of infill walls is investigated by means of modal analyses of two-, three-, and four-bay RC frames with a number of stories ranging from 3 to 8. Both uniformly and non-uniformly infilled frames are considered in numerical analyses, where infill walls are simulated by adopting the model of equivalent compression strut. Consequently, spatial distribution of effective earthquake forces, modal static base shear force response of frames, modal responses of story shears from external excitation vector and lateral floor displacements are obtained. It is found that, infill walls and their arrangement over the height of the frame structure affect the spatial distribution of modal inertia forces, as well as the considered response quantities. Moreover, the amount of influence varies in stories, but is not very dependent to bay number of frames.

• 천문학회보
• /
• 제46권1호
• /
• pp.38.3-38.3
• /
• 2021

We are developing an optomechanical design of infrared telescope for the CubeSat and Unmanned Aerial Vehicle (UAV) which adapts the Linear Astigmatism Free- Three Mirror System in the confocal off-axis condition. The small entrance pupil (diameter of 40 mm) and the fast telescope (f-number of 1.9) can survey large areas. The telescope structure consists of three mirror modules and a sensor module, which are assembled on the base frame. The mirror structure has duplex layers to minimize a surface deformation and physical size of a mirror mount. All the optomechanical parts and three freeform mirrors are made from the same material, i.e., aluminum 6061-T6. The Coefficient of Thermal Expansion matching single material structure makes the imaging performance to be independent of the thermal expansion. We investigated structural characteristics against external loads through Finite Element Analysis. We confirmed the mirror surface distortion by the gravity and screw tightening, and the overall contraction/expansion following the external temperature environment change (from -30℃ to +30℃).

• 한국신재생에너지학회:학술대회논문집
• /
• 한국신재생에너지학회 2010년도 추계학술대회 초록집
• /
• pp.44.2-44.2
• /
• 2010

차세대 태양전지로써 플렉서블 태양전지에 대한 연구가 활발하다. CIS 박막태양전지의 경우도 Glass base 태양전지 시스템 연구와 더불어 금속과 플라스틱 등 연성 기판재를 이용한 전지 시스템에 관한 연구가 진행 되고 있다. 그러나 태양전지의 핵심 부자재라고 할 수 있는 기판재에 대한 체계적인 연구는 미흡한 실정이다. 특히 플렉서블 박막태양전지용 기판재와 그 위에 적층되어 태양전지를 구성하는 박막 소재의 열팽창 거동들 사이에 차이가 있어 태양전지 시스템에 결함을 야기할 수 있다. 본 연구에서는 플렉서블 태양전지용으로 적용되거나 연구되고 있는 SUS 300 계열과 SUS 400번 계열을 중심으로 철계 연성 기판재의 열팽창 거동을 비교 분석하였다. 그리고 CIS 박막태양전지 제조 공정인 고온 박막 생성 공정의 열분석을 통해 기판재의 성능을 평가 하였다.

• 대한기계학회논문집
• /
• 제18권5호
• /
• pp.1245-1252
• /
• 1994

A solution of heat transfer problems of composite materials has been tried using homogenization technique. Homogenization technique, which was derived by applying asymptotic expansion to the standard finite element method, helped compute the equivalent thermal conductivity matrices of base cells which constituted the composite material with repeated patterns. The homogenization technique made it possible to compute the solution of the heat transfer problem of composite materials with lower degrees of freedom compared to those of other numerical methods. The equivalent thermal conductivities computed by computed by homogenization technique are also applicable to other numerical methods such as finite difference method.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 1988년도 전기.전자공학 학술대회 논문집
• /
• pp.525-528
• /
• 1988

In this paper, a new multi-output logic minimization algorithm is presented. A base minterm is selected in the given function and the prime implicant is obtained by expanding it in the order of the expansion set that is decided by heuristic method. Input-oriented expansion procedure is used to reduce fan-in and fan-out number. To show the effectiveness of this algorithm, comparative run time with other minimization algorithm is given.

• 대한설비공학회:학술대회논문집
• /
• 대한설비공학회 2008년도 하계학술발표대회 논문집
• /
• pp.177-183
• /
• 2008

For 10 kW-class Stirling engine using scroll expander and scroll compressor, considerations on thermal expansion of the fixed and orbiting scroll members of the scroll expander due to high gas temperature at the expander inlet has resulted in adopting of the keys between the fixed scroll and main frame for the fixed scroll side and spring type insertion between the orbiting scroll base plate and supporting holders for orbiting scroll side. Dynamic analysis on the fixed and orbiting scroll members and the shafts of the scroll expander showed that using of these devices for complying thermal expansion caused large variations of the forces acting on the fixed scroll keys and on the power transmitting shafts and also on the shaft bearings.

• 한국분말야금학회:학술대회논문집
• /
• 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part 1
• /
• pp.377-378
• /
• 2006

Thermal management technology is a critical element in all new chip generations, caused by a power multiplication combined with a size reduction. A heat sink, mounted on a base plate, requires the use of special materials possessing both high thermal conductivity (TC) and a coefficient of thermal expansion (CTE) that matches semiconductor materials as well as certain packaging ceramics. In this study, nano tungsten coated copper powder has been developed with a wide range of compositions, 90W-10Cu to 10W-90Cu. Powder technologies were used to make samples to evaluate density, TC, and CTE. Measured TC lies among theoretical values predicted by several existing models.

• 지적과 국토정보
• /
• 제51권2호
• /
• pp.125-139
• /
• 2021

수도권 지하철 노선확장 사업을 통해 수도권 거주민의 대중교퉁 접근성은 지속적으로 향상되고 있다. 이러한 대중교통 접근성은 주거지 선택 시 가장 중요한 요소 중 하나로 지하철 노선확장에 따른 접근성 향상이 주택가격에 미치는 영향을 정량적으로 추정하는 것은 주택정책에 있어 중요하다. 이 연구는 노선신설에 따라 최근접 지하철역의 변화없이 발생하는 다른 지하철역까지의 통행시간 단축을 네트워크 확장효과로 정의하고, 이것이 주택가격에 미치는 영향력을 확인하고자 한다. 이를 위해 2012년부터 2018년까지 서울시 아파트 전월세확정신고자료를 이용하여 월세로 전환 후, 수정반복매매모형을 통해 시계열적으로 분석하였다. 그 결과, 기준이 되는 기간(2012~2014년)에 비해 비교기간 (2017~2018년)에 네트워크 확장효과가 서울시 아파트 월세가격에 미치는 영향력이 상대적으로 더 증가했으며, 이는 지하철 네트워크 확장효과가 주택의 임대료 형성에 유의미한 영향을 미친다는 것을 시사한다. 또한, 분석과정에서 네트워크 확장효과의 상하위 아파트 그룹을 비교한 결과, 네트워크 확장 효과 하위그룹보다 상위그룹에서 영향력의 상승폭이 상대적으로 컸으며, 이를통해 네트워크 확장 효과의 정도에 따라 주택의 가치에 자본화되는 수준도 다르다는 것을 확인할 수 있었다.

• 한국지진공학회:학술대회논문집
• /
• 한국지진공학회 2002년도 춘계 학술발표회 논문집
• /
• pp.266-274
• /
• 2002

A typical case where the effects of prying in the base angle type anchorage system with expansion bolt. This connection consists of an angle which is attathed to an equipment cabinet and bolted to a concrete slab via an expantion bolt. A seismic analysis of the cabinet may indicate a vertical load, P, transferred to the vertical leg of the angle due to overturning of the cabinet. Due to the eccentricity, b(e), and the continuous beam action in the base member, the load resisted by the bolt will be amplified by a factor λ. Thus, in this study, experimental evaluation of the anchorage system is executed.