• 한국강구조학회 논문집
• /
• 제16권4호통권71호
• /
• pp.433-442
• /
• 2004

본 연구는 Eurogode 3 Part 1.3을 근거하여 온도증가에 따른 압축을 받는 냉간성형 C-형강 기둥의 플랜지와 웨브의 탄성국부좌굴 응력 해석 프로그램을 개발하였다. 고온에서 응력-변형률 관계식은 Eurocode 3 Part 1.2를 근거하였다. 온도증가에 따른 압축을 받는 냉간성형 C-형강의 임계온도와 탄성국부좌굴 응력은 본 연구에서 개발한 컴퓨터 프로그램에 의해 해석하였고, 해석 예에 대한 비교 고찰을 하였다.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• 제5권11호
• /
• pp.2068-2086
• /
• 2011

Based on the quincunx sub-sampling grid, the New Interleaved Hierarchical INTerpolation (NIHINT) method is recognized as a superior pyramid data structure for the lossless and progressive coding of natural images. In this paper, we propose a new image interpolation algorithm, Edge Adaptive Hierarchical INTerpolation (EAHINT), for a further reduction in the entropy of interpolation errors. We compute the local variance of the causal context to model the strength of a local edge around a target pixel and then apply three statistical decision rules to classify the local edge into a strong edge, a weak edge, or a medium edge. According to these local edge types, we apply an interpolation method to the target pixel using a one-directional interpolator for a strong edge, a multi-directional adaptive weighting interpolator for a medium edge, or a non-directional static weighting linear interpolator for a weak edge. Experimental results show that the proposed algorithm achieves a better compression bit rate than the NIHINT method for lossless image coding. It is shown that the compression bit rate is much better for images that are rich in directional edges and textures. Our algorithm also shows better rate-distortion performance and visual quality for progressive image transmission.

• Journal of Chest Surgery
• /
• 제34권11호
• /
• pp.875-878
• /
• 2001

배경: 비록 경화요법이 정맥류를 치료하는데 확립된 방법일지라도 그 성공률에는 차이가 있다. 따라서 이 연구의 목적은 압박경화요법의 치료효과와 합병증을 평가하는데 있다. 대상 및 방법: 2000년 12월부터 2001년 9월까지 일차성 하지 정맥류 환자중 압박경화요법을 시행 받은 39명(50예의 하지)을 대상으로 하였다. 주사한 직후 정맥류의 경로를 따라서 탈지면롤을 댄 후, 다시 class II 압박스타킹을 신겼다. 환자는 치료효과와 합병증의 정도를 보기 위해서 시술후 5일, 1주, 2주, 6주에 평가되었다. 결과: 환자의 연령은 26세에서 66세까지로 평균 45.3세이었으며 여자 36명, 남자 3명이었다. 모든 환자에서 경화요법의 결과는 우수하였다. 50례의 하지 중 5례에서만 작은 합병증이 있었는데 2례의 혈관내 작은 응혈, 2례의 색소침착, 1례의 압박으로 인한 수포가 있었다. 이는 특별한 치료 없이 모두 회복되었다. 결론: 국소 압박도구로써 탈지면롤은 매우 손쉽고 효과적이며, 압박경화용법은 경제적 부담이 적고 안전하고 효과적인 치료법이다.

• 대한용접접합학회:학술대회논문집
• /
• 대한용접접합학회 2000년도 특별강연 및 추계학술발표대회 개요집
• /
• pp.151-154
• /
• 2000

• 유체기계공업학회:학술대회논문집
• /
• 유체기계공업학회 2003년도 유체기계 연구개발 발표회 논문집
• /
• pp.251-256
• /
• 2003

The detailed flow characteristics inside a compression chamber due to the orbiting motion of a scroll is studied numerically. The orbiting motion of a scroll is modelled at 7 orbiting angles. At each orbit angle, the central compression chamber is modelled. All computations are carried by using an in-house code. It is based on the SIMPLE algorithm. Computation results show that the flow structure inside the compression chamber is dependent on the orbit angle. The pressure variation inside the compression chamber also shows great dependence on the orbit angle. The pressure variation shows local maxima when the orbiting motion of a scroll directs toward the center of the compression chamber.

• Steel and Composite Structures
• /
• 제31권2호
• /
• pp.125-131
• /
• 2019

This paper presents the results of an experimental study to investigate the mechanical behavior of partially encased composite columns confined by CFRP under axial compression. The results show that the failure of the partially encased composite columns confined by CFRP occurred due to rupture of the CFRP followed by local buckling of the steel flanges. External wrapping of CFRP effectively delayed the local buckling of the steel flanges. The load carrying capacity of the column increased with the application of CFRP sheet. And the enhancement effect of the column was increased with the number of CFRP layer.

• 천문학회지
• /
• 제56권2호
• /
• pp.225-229
• /
• 2023

We investigated an emerging magnetic loop dynamically formed on the Sun, which has the effective footpoint heating source that may play a key role in heating a solar atmosphere with free magnetic energy in it. It is suggested that the heating source could be related to local compression of a plasma in the emerging loop by means of Lorentz force, which converts the magnetic energy to the internal energy of the plasma that is used to reaccelerate a decelerated downflow along the loop, eventually generating the source when the kinetic energy of the downflow is thermalized. By analyzing very high-cadense data obtained from a magnetohydrodynamic simulation, we demonstrate how the local compression is activated to trigger the generation of the heating source. This reveals a characteristic of the emerging loop that experiences a dynamic loop-loop interaction, which causes the local compression and makes the plasma gain the internal energy converted from the magnetic energy in the atmosphere. What determines the characteristic that could distinguish an illuminated emerging loop from a nonilluminated one is discussed.

• 한국윤활학회:학술대회논문집
• /
• 한국윤활학회 1998년도 제27회 춘계학술대회
• /
• pp.206-211
• /
• 1998

This paper presents the deformation characteristics of cam ring in a balanced type vane pump. Cam ring is operated in the condition of high pressure. Therefore the local deformation of cam ring affects the characteristics of compression, vane motion and noise and vibration. We analyzed the deformation of cam ring in three types by using the finite element method. As results of analysis, deformed shape of cam ring and the effects of deformation on the compression are presented.

• 한국컴퓨터정보학회논문지
• /
• 제3권4호
• /
• pp.97-102
• /
• 1998

본 논문에서는 영상을 효과적으로 부호화하고 높은 압축률에서도 원 영상을 잘 복원할 수 있는 프랙탈 압축방법을 제안하였다. 주어진 SNR 허용오차에 대해 Fisher l)방법과본 논문에서 제안한 방법이 모든 문턱치에서 압축비가 기존의 방법보다 더 높음을 보여준다. 이 지역적인 반복함수계가 PIFS 정보기억용량을 레인지 블록당 48비트에서 40비트로 줄일수 있어 압축시간이 개선됨을 보인다.

• Computers and Concrete
• /
• 제1권4호
• /
• pp.433-455
• /
• 2004

The paper presents results of FE-calculations on shear localizations in quasi-brittle materials during both an uniaxial plane strain compression and uniaxial plane strain extension. An elasto-plastic model with a linear Drucker-Prager type criterion using isotropic hardening and softening and non-associated flow rule was used. A non-local extension was applied in a softening regime to capture realistically shear localization and to obtain a well-posed boundary value problem. A characteristic length was incorporated via a weighting function. Attention was focused on the effect of mesh size, mesh alignment, non-local parameter and imperfections on the thickness and inclination of shear localization. Different methods to calculate plastic strain rates were carefully discussed.