• 제목/요약/키워드: Tension

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Communicating Hydrocephalus Onset Following a Traumatic Tension Pneumocephalus

  • Lee, Jin-Sung;Ahn, Sora;Eom, Ki Seong
    • 대한두개안면성형외과학회지
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    • 제17권4호
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    • pp.225-228
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    • 2016
  • The entrapment of intracranial air from the check valve system results in a tension pneumocephalus. It should be distinguished from simple pneumocephalus because they are intracranial space-occupying masses that can threaten life. Communicating hydrocephalus is a serious and frequent complication of post-traumatic head injury. Head injury is one of the most common causes in etiopathogenesis of communicating hydrocephalus. Here, we describe a case of a 65-year-old man who developed communicating hydrocephalus after a post-traumatic tension pneumocephalus. To the best of our knowledge, this is the first reported case of communicating hydrocephalus developed after a post-traumatic tension pneumocephalus. Although the exact pathogenic mechanisms underlying the cascade following trauma remain unclear, communicating hydrocephalus after a tension pneumocephalus could be considered a possible complication.

The Design of Width Controller by using Looper Tension Control of Finishing Mill in Hot Strip Mill

  • Han, Chang-Soo;Kim, Jeong-Ha
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2001년도 ICCAS
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    • pp.68.6-68
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    • 2001
  • There is a looper for the safety threading between stands in finishing mill. In this looper system, it is 2 inputs 2 outputs MIMO )Multi Input Multi Output) system, which has two inputs that are the angle of looper and the tension of Strip and has two outputs that are the torque of looper motor and the speed of Mill Motor. In tension controller of looper, it calculates the range of tension variation into the compensation value of speed and outputs to the speed controller of Mill Motor, so that it controls the tension of strip between stands. In this study, using this tension controller of looper, we adjust the establishment value of ...

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고무재료의 이축 인장시험에 관한 연구 (A Study on the Equi-biaxial Tension Test of Rubber Material)

  • 김동진;김완두;김완수;이영신
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2003년도 춘계학술대회
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    • pp.425-430
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    • 2003
  • The material properties of rubber was determined by the experiments of uniaxial tension, uniaxial compression, planer tension, equi-biaxial tension and volumetric compression. In compression test, it is difficult to obtain the pure state of compression stress and strain due to friction force between the specimen and compression platen. In this study, the stress and strain data from the equi-biaxial tension test were converted to compression stress and strain and compared to a perfect state of simple compression data when friction was zero. The compression test device with the tapered platen was proposed to overcome the effect of friction. It was turned out that the relationship of the stress and strain using the tapered platen was in close agreement with the pure compressive state.

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봉사장력에 따른 본봉 Seam의 구조해석 (Analysis of the Structure of Lockstitched Seam according to Sewing Thread Tension)

  • 서정권
    • 한국의류산업학회지
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    • 제3권1호
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    • pp.25-30
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    • 2001
  • In order to investigate the influence of thread tension on the structure of lockstitch seam, stitch tightness and seam balance ratio are measured at various tensions of needle thread and bobbin thread. The structure of lockstitch was shown in terms of skeleton stitch models to obtain quantitative analysis of stitch tightness. The balanced seam formed to the rectangu1ar stitch model under low bobbin thread tension, but the fabric tightness produced by interlaced needle and bobbin thread under high bobbin thread tension. In this paper, new equation to obtain seam balance ratio was proposed for a lockstitch seam. By using the new equation, the seam balance ratio was not affected by the stitch density and fabric thickness. In order to form the balanced seam, the ratio on tension of needle thread and bobbin thread was about 6:1~7:1 in this experiment.

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ER 브레이크를 이용한 와이어 방전가공기의 장력제어 (Tension Control of a Wire Cut Discharge Machine Using ER Brake)

  • 김기선;조명수
    • 한국공작기계학회논문집
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    • 제13권5호
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    • pp.24-29
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    • 2004
  • This paper presents the tension control of a wire-cut discharge machine using electrorheological(E,R) fluid based brake system. On the basis of the tension level required in the machine, an appropriate size of the ER brake which features design simplicity, fast response and salient controllability is designed. Considering the Bingham property of ER fluid and actuator response time, the governing equation of the ER brake is derived. And a tension propagation of wire electrode is modeled via frequency response. The tension control performance of the discharge machine is simulated by using a robust sliding mode controller.

롤투롤 와인딩 시스템에서 테이퍼 장력과 감김롤 응력분포에 관한 연구 (Effect of Taper Tension Profiles on Radial Stress of a Wound Roll in Roll-to-roll Winding Process)

  • 이창우
    • 한국정밀공학회지
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    • 제31권2호
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    • pp.125-131
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    • 2014
  • Winding is an integral operation in almost every roll-to-roll continuous process and center-winding is suitable and general scheme in the winding system. However, the internal stresses within center-wound rolls can cause damage such as buckling, spoking, cinching, etc. It is therefore necessary to analyze the relationship between taper tension in winding section and internal stress distribution within center-wound roll to prevent the winding failure. In this study, an optimal taper tension control method with parabolic taper tension profile for producing high quality wound roll was developed. The new logic was designed from analyzing the winding mechanism by using the stress model in center-wound rolls. The performance of the proposed taper tension profile was verified experimentally.

Bi-2223/Ag 고온초전도 선재의 기계적 특성 평가 (Evaluation of mechanical properties of Bi-2223/Ag HTS tapes)

  • 하홍수;이동훈;양주생;최정규;윤진국;하동우;오상수;권영길;김상철
    • 한국초전도ㆍ저온공학회논문지
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    • 제4권1호
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    • pp.45-59
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    • 2002
  • Evaluation of the mechanical properties of Bi-2223/Ag HTS tapes was carried out by the tension and bending tests. Most of the Bi-2223/Ag tapes retained critical current up to 10 kgf/mm$_2$ axial tension stress, and 0.2% tension strain at room temperature. Applied tension strain exceeding 0.3% in superconducting tapes at 77 K leaded to rapid degradation of the critical current. It was observed that the more filaments, the better axial tension property at 77 K, self-field The influence of bending strain on critical current degradation was revealed to be less sensitive for Bi-2223/Ag HTS tapes with a more number of filaments and higher silver ratio.

타이어 측면 형상변화에 따른 CARCASS 장력분포 변동에 관한 유한요소 해석 (Finite Element Analysis for the Variation of CARCASS Tension Distribution to the Sidewall Contour Change)

  • 정현성;이홍우;하대율;김상현;조진래;김남전;김기운
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2000년도 추계학술대회논문집A
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    • pp.438-445
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    • 2000
  • Tire performance is significantly influenced by the cord tension distribution, and which is governed by the tire shape. To increase the tire performance, it is very important for one to find the shape with the ideal distribution of tension. But it is not easy to find such an optimal tire shape. Therefore, in order for the successful tire-shape optimization, we need to investigate how the change of tire shape influences on the cord tension. In this paper, we intend to numerically analyse the relation between the carcass shape and the cord tension.

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고로슬래그 및 플라이애쉬를 혼입한 폴리머 시멘트 모르타르의 인장접착강도 (Adhesion in Tension of Polymer-Modified Mortars with Blast-Furnace Slag and Fly ash)

  • 조영국
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2017년도 춘계 학술논문 발표대회
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    • pp.232-233
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    • 2017
  • The purpose of this study is to evaluate the Adhesion in tension of cement mortar according to adding admixtures such as polymer dispersions, blast-furnace slag and fly ash. From the test results, the adhesion in tension is seriously affected by type of polymer compared with polymer-binder ratios and types of admixture. The maximum adhesion in tension of EVA- modified mortar is about 1.46 times, the cement mortar. It is apparent that the adhesion in tension of polymer-modified mortars according to adding two admixtures is much more improved irrespective of polymer-binder ratio.

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다단인발공정에서 후미인장응력이 중심파괴에 미치는 영향 (Effect of Back Tension in Multi-pass Drawing on the Central Bursting Defect)

  • 이성원;김민철;심규하;전만수
    • 소성∙가공
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    • 제21권5호
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    • pp.291-297
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    • 2012
  • In this paper, the effect of back tension in multi-pass drawing or wiredrawing on the central bursting defect is investigated using finite element predictions. A rigid-plastic finite element method was used together with the McClintock damage model. Central bursting defects under different back tension stress values ranging from 0% to 20% of the yield strength of the material were predicted and they were compared to understand the effect of the back tension stress values on the central bursting defect. It is found that the level of back tension has a strong influence on the cumulative damage. Thus, higher back tension raises the possibility of the central bursting defect occurring, even though it decreases the interfacial pressure between the die and the work piece.