• 제목/요약/키워드: Collapse time

검색결과 577건 처리시간 0.021초

Surgical outcomes in dogs with tracheal collapse treated with a novel cross-and-hook braided endoluminal stent

  • Uemura, Akiko;Ozai, Yusuke;Hamabe, Lina;Yoshida, Tomohiko;Tanaka, Ryou
    • Journal of Veterinary Science
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    • 제23권3호
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    • pp.46.1-46.8
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    • 2022
  • Background: Stenting is an effective treatment option for tracheal collapse in dogs. Cross-braided tracheal stents are currently the norm in veterinary medicine, but cross-and-hook braided stents have recently been adopted in human medicine. We examined whether stents manufactured using this novel braiding technique provided additional advantages for the treatment of tracheal collapse in dogs. Objectives: To evaluate the outcomes of cross-and-hook braided stent implantation in the treatment of tracheal collapse in dogs. Methods: The medical records of 22 client-owned dogs that underwent luminal placement of cross-and-hook braided Fauna Stents for the treatment of tracheal collapse between January 2018 and July 2021 were examined and data on canine signalment, clinical signs, diagnostic test results, surgical outcomes, and postoperative complications were retrieved and analyzed statistically. Results: Twenty-six stents were surgically implanted, with 20 dogs (90.9%) receiving one stent and the remaining two (9.1%) receiving two or more stents. All dogs survived the procedure. The median survival time at a median follow-up of 990 days was 879 days. At the final follow-up examination, loss or mild improvement of cough was observed in all dogs. Conclusions: Compared with conventional lumen stents, the cross-and-hook braided Fauna Stent offered a higher survival rate and improved clinical symptoms in all patients. The results of this study suggest that the Fauna Stent may be a promising treatment option for dogs with tracheal collapse.

재팽창 폐부종 치험 2례 보고 (Re-expansion Pulmonary Edema -2 Cases Report-)

  • 강경민
    • Journal of Chest Surgery
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    • 제28권1호
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    • pp.81-84
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    • 1995
  • Re-expansion pulmonary edema following pneumothorax or hemothorax is clinically uncommon but occasionally life threatening. Clinical details are given of two patients.Ipsilateral pulmonary edema were developed after chest tube insertion due to spontaneous pneumothorax in case I and after evacuation of postoperative hemothorax in case II. The patients were treated with frequent bronchial toilet.The administration of colloid solution and diuretics was effective. The possible mechanisms underlying the edema are discussed.Both increased time of collapse and suction tended to correlate with reexpansion edema.The present two cases provided evidence for longstanding lung collapse and immediate application of suction.

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복잡(複雜)한 형상(形狀)의 초기(初期)처짐을 가진 실선(實船)의 Panel의 압괴강도(壓壞强度) 간이추정법(簡易推定法) (Estimation of the Ultimate Compressive Strength of Actual Ship Panels with Complex Initial Deflection)

  • 백점기;김건
    • 대한조선학회지
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    • 제25권1호
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    • pp.33-46
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    • 1988
  • This paper describes a simplified method for estimation of the ultimate compressive strength of actual ship panels with initial deflection of complex shape. The proposed method consists of the elastic analysis using the large deflection theory and the rigid-plastic analysis based on the collapse mechanism which also includes the large deformation effect. In order to reduce the computing time for the elastic large deflection theory and the rigid-plastic analysis based on the collapse mechanism which also includes the large deformation effect. In order to reduce the computing time for the elastic large deflection analysis, only one term of Fourier series for the plate deflection is considered. The results of the proposed method are in good agreement with those calculated by the elasto-plastic large deflection analysis using F.E.M. and the computing time of the proposed method is extremely short compared with that of F.E.M.

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지하수 용출과 단층파쇄 위치에 따른 터널 거동 연구 (A Study on Behaviour of Tunnel Considering the Location of Groundwater Leaching and Fault Fracture Zone under Tunnel Construction)

  • 손용민;김낙영;민경준
    • 한국지반환경공학회 논문집
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    • 제16권12호
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    • pp.37-43
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    • 2015
  • 터널구조물은 굴착 주변 지반의 강도를 활용하는 구조물로서 지반특성이 가장 중요하다. 단층파쇄대와 같은 취약한 지반 조건이 터널 굴착 구간에 존재하는 경우, 특히 단층파쇄대와 지하수 용출이 동시에 발생하는 조건에서는 터널 굴착 중 과다변위 또는 붕락 등이 자주 발생한다. 이러한 단층파쇄대는 터널 굴착 중 변위 및 붕락의 방향을 결정해주는 중요한 요인이 된다. 단층파쇄대의 규모 및 지표부와의 방향성에 따라 터널 거동 특성이 결정되고 이와 더불어 지하수 용출이 발생되는 경우에는 터널 굴착 중 발생되는 변위 및 붕락 특성이 시간 의존적인 거동을 하게 되는 결정적인 요인이 된다. 단층파쇄대 구간에서 지하수 용출을 해석적인 방법으로 예측하거나 지하수 용출과 단층파쇄대의 상호거동을 분석하였을 경우에 정확하게 예측을 하기가 어렵다. 따라서 단층파쇄대와 지하수가 동시에 발생하는 구간에서는 해석적인 분석방법으로는 한계가 있으므로 실제 시공사례를 분석하여 거동을 종합적으로 예측하는 것이 필요하다. 본 연구에서는 단층파쇄대의 위치에 따른 실제 터널 거동 특성을 분석하였다.

사력댐 사석 보호공의 붕괴 지연 효과에 대한 실험 연구 (Experimental Study of Collapse Delay Effect of Riprap on Dam Slope)

  • 정석일;김승욱;김홍택;이승오
    • 한국방재안전학회논문집
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    • 제11권1호
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    • pp.31-38
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    • 2018
  • 국내 중소규모 저수지의 99.1%는 흙댐으로, 건설비용이 저렴하여 용이한 시공성을 갖고 있다. 그러나 흙댐은 월류에 취약하기 때문에, 홍수 시 급격한 붕괴 가능성이 있다. 이러한 붕괴가 발생할 경우 급격한 홍수량 증가로 이어지기 때문에, 하류 치수 안전성이 위협 받을 가능성이 크다. 이에 본 연구에서는 흙댐 사면에 포설한 사석의 붕괴 지연효과를 실험을 통해 검토하였다. 실험은 사각단면의 직선형 개수로에서 수행하였으며, 보호공 사석의 크기를 3가지로 결정하였다. 선행 연구들과 차이점은 부정류로 실험을 수행한 것이며, 대상은 일반적인 형태의 가물막이로 결정하였다. 실험결과 차원해석 및 선행연구를 이용하여 서석보호공이 포설된 흙댐 붕괴 시간에 대한 새로운 공식을 제시하였다. 또한 사석 보호공이 설치된 경우 실험을 통해 붕괴 지연효과에 대해 검토한 결과 포설된 사석의 2배 이상의 효과가 있는 것으로 확인되었다. 본 연구 결과는 EAP (Emergency Aciton Plan) 수립 및 제방 설계와 같은 하천 계획에 도움이 될 것으로 판단된다.

SMAC법을 이용한 물기등 붕괴의 가시화 (Visualization of the Water Column Collapse by using SMAC Method)

  • 김남형;김남국
    • 한국수자원학회논문집
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    • 제34권6호
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    • pp.605-615
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    • 2001
  • 수치시뮬레이션 기법 중 하나인 SMAC법은 시간의 변화에 따른 유동의 현상을 해석하기 위해 MAC법을 수정 한 기법이다. 비압축 점성 흐름을 풀기 위해 Navier-Stokes 방정식을 사용하였으며, 유동을 가시화하기 위해 마커입자가 사용되었다. 본 연구에서는 SMAC법을 사용한 2차원 물기등 붕괴현상의 수치시뮬레이션을 수행하였으며, 시뮬레이션 결과는 Martin과 Moyce의 실험 결과 및 MPS법의 계산결과와 비교하였고, 좋은 결과가 얻어졌다. 또한, 이 수치시뮬이션은 댐 붕괴와 같은 수공구조물의 붕괴현상에 적용할 수 있겠다.

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정상 견에서 수액세트 점적통을 이용한 새로운 기관 외부 보철링의 적용 (Application of new external total ring prostheses made by drip chamber of intravenous administration set in normal dogs)

  • 정상휘;정순욱
    • 대한수의학회지
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    • 제44권1호
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    • pp.137-141
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    • 2004
  • The purpose of this study was to compare easiness of application of polypropylene external total ring prosthesis (PPTRP, Group A) with that of polyvinylchloride external total ring prosthesis (PVCTRP, Group B), which were used for surgical correction of tracheal collapse in dogs. PPTRP was made from 3 ml syringe and PVCTRP from the drip chamber of intravenous administration set. Prostheses of group A (n=5) and B (n=5) were placed to cervical trachea in clinically normal 10 dogs, respectively weighing between 4 kg and 6 kg. There were mild coughing and swelling in one to three dogs of both groups for 3 days after surgery. No exercise intolerance was observed in both groups after surgery. There were no different results of clinical signs and radiographic views after surgery between group A and group B. The time (mean${\pm}$SD) to make total ring prosthesis, group A took $23.2{\pm}1.9$ minutes which was remarkably longer than that $(4.6{\pm}0.3)$ of group B. Also, the time to place around trachea, group A required $61.8{\pm}8.8$ minutes and group B $38.4{\pm}8.0$ minutes. Conclusionly, PVCTRP was timesaving and easier to make, fix, and suture than those of PPTRP. PVCTRP may be used alternatively to PPTRP for the tracheal collapse to treat in dogs.

An Adaptive Undervoltage Load Shedding Against Voltage Collapse Based Power Transfer Stability Index

  • Nizam, Muhammad;Mohamed, Azah;Hussain, Aini
    • Journal of Electrical Engineering and Technology
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    • 제2권4호
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    • pp.420-427
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    • 2007
  • This paper highlights the comparison of a proposed methods named adaptive undervoltage load shedding based PTSI techniques for undervoltage load shedding and two previous methods named Fixed Shed Fixed Delay (FSFD) and Variable Shed Variable Delay (VSVD) for avoiding voltage collapse. There are three main area considerations in load shedding schemes as the amount of load to be shed, the timing of load shedding event, and the location where load shed is to be shed. The proposed method, named as adaptive UVLS based PTSI seem to be most appropriate among the uncoordinated schemes. From the simulation result can be shown the Adaptive UVLS based PTSI give faster response, accurate and very sensitive control for the UVLS control technique. This technique is effectively when calculating the amount to be shed. Therefore, it is possible to bring the voltage to the threshold value in one step. Thus, the adaptive load shedding can effectively reduce the computational time for control strategy.

Application of shakedown analysis technique to earthquake-resistant design of ductile moment-resisting steel structures

  • Lee, Han-Seon;Bertero, Vitelmo V.
    • Structural Engineering and Mechanics
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    • 제1권1호
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    • pp.31-46
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    • 1993
  • The motivations of the application of shakedown analysis to the earthquake-resistant design of ductile moment-resisting steel structures are presented. The problems which must be solved with this application are also addressed. The illustrative results from a series of static and time history nonlinear analyses of one-bay three-story steel frame and the related discussions have shown that the incremental collapse may be the critical design criterion in case of earthquake loading. Based on the findings, it was concluded that the inelastic excursion mechanism for alternation load pattern, such as in earthquake, should be the sidesway mechanism of the whole structure for the efficient mobilization of the structural energy dissipating capacity and that the shakedown analysis technique can be used as a tool to ensure this mechanism.

적층구성이 CFRP 사이드 부재의 충돌안전성에 미치는 영향 (Influence of Stacking Condition on Collision Safety of CFRP Side Member)

  • 황우채;양인영
    • 한국안전학회지
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    • 제29권3호
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    • pp.14-19
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    • 2014
  • The global demand for reduction in the weight of automobiles has led many countries to focus on the development of hybrid, eco-friendly, and electric cars. Reduction in the weight of materials can both increase fuel efficiency and maximize automobile performance. Therefore, the design of automobile should be inclined towards the safety aspects. but at the same time, it also consider reducing the structural weight of an automobile. In this study, CFRP side members with circular and double hat shaped section was manufactured. The impact collapse tests performed with change of the stacking condition, such as variation of interface number and outerlayer angle. The impact collapse load and absorbed energy were quantitatively analyzed according to the changes in section shapes and stacking condition. This analysis was performed to obtain design data that can be applied in the development of optimum lightweight members for automobiles.