• 제목/요약/키워드: Tension response

검색결과 565건 처리시간 0.029초

강제동요 시험을 이용한 모형 계류삭의 동적 응답 연구 (A Research on Dynamic Tension Response of Model Mooring Chain by Forced Oscillation Test)

  • 조석규;홍사영;홍섭;김현조
    • 한국해양공학회지
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    • 제19권3호
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    • pp.39-46
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    • 2005
  • A series of forced oscillation tests on a model mooring chain was carried out to investigate dynamic tension characteristics. The model test was conducted at two different water depths to gather basic data for a 'truncated mooring test' and 'hybrid mooring test'. The truncated and hybrid mooring tests are important for overcoming the limitation of water depth that existed in previous model tests. The resultant tension RAO provides a good possibility of approximation of dynamic tension by equivalent weight adjustment for different water depths. Because the hybrid mooring test is an adequate combination of model test and simulation, an accurate simulation model for the mooring system is essential. The simulation results show good agreement with model test results.

심근세포내 칼슘 이온 활용도에 미치는 Vanadate 의 효과 (Effects of Vanadate on the intracellular Calcium ion activities in mvocardial cells)

  • 이정렬;김우겸
    • Journal of Chest Surgery
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    • 제21권2호
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    • pp.291-298
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    • 1988
  • The effect of Vanadate on the isometric contraction, membrane potential and intracellular calcium ion activities of rabbit myocardial cells were investigated, using calcium selective microelectrode, filled with neutral calcium ion carrier, ETH-1001. The resting tension, the membrane potential and the intracellular calcium ion activities were recorded in normal Tyrode solution and compared with those in the contracture induced by 10 mM Vanadate. The following results were obtained: 1. The dose-response relationship between the contraction of Vanadate and twitch tension showed near-maximum response in 5mM with no corresponding changes in action potential. 2. The resting tension increased up to the amplitude of a control twitch in 10mM Vanadate with resting membrane potential, hyperpolarized. 3. Increase in intracellular calcium ion activities proceeded the contracture by 10mM Vanadate which were restored to the control level in accordance with a decrease of intracellular calcium ion activities. 4. The amplitude of contractures by 10mM Vanadate were 90-120% of the control twitch tension in which the intracellular calcium ion activities were increased about 70 times from p Ca, 7.1 in the control to p Ca, 5.8 in contractures.

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강제동요 시험을 이용한 모형 계류삭의 동적 응답 연구 (A Research on Dynamic Tension Response of Model Mooring Chain by Forced Oscillation Test)

  • 김현조;홍사영;홍섭;조석규
    • 한국해양공학회:학술대회논문집
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    • 한국해양공학회 2002년도 추계학술대회 논문집
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    • pp.134-141
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    • 2002
  • A series of forced oscillation test on model mooring chain was carried out to investigate dynamic tension characteristics. The model test was conducted at two different water depth to gather basic data for 'truncated mooring test' and 'hybrid mooring test'. The truncated and hybrid mooring test are highly recommended to overcome the limitation of water depth in model test recently. The resultant tension RAO gives good possibility of approximation of dynamic tension by equivalent weight adjustment for the ratio of water depth in different water depth. Because the hybrid mooring test is the adequate combination of model test and simulation, accurate simulation model on mooring system is essential. The simulation results show good agreement with model test results.

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소성 비대칭성을 갖는 HCP 소재의 국부변형 및 네킹해석 (Localized Necking in a Round Tensile Bar for a HCP Material Considering Tension-compression Asymmetry in Plastic Flow)

  • 윤종헌;이정환
    • 소성∙가공
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    • 제21권5호
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    • pp.285-290
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    • 2012
  • In spite of progress in predicting ductile failure, the development of a macroscopic yield criterion to describe damage evolution in HCP (hexagonal close-packed) materials remains a challenge. HCP materials display strength differential effects (i.e., different behavior in tension versus compression) in their plastic response due to twinning. Cazacu and Stewart(2009) developed an analytical yield criterion for porous material containing randomly distributed spherical voids in an isotropic, incompressible matrix that shows tension-compression asymmetry. The goal of the calculations in this paper is to investigate the effect of the tension-compression asymmetry on necking induced by void nucleation, evolution and consolidation. In order to investigate the effect of the tension-compression asymmetry of the matrix on necking and fracture initiation, three isotropic materials A, B, and C were examined with different ratios of tension-compression asymmetry. The various types of material had BCC, FCC, and HCP crystal structures, respectively. The ratio between tension and compression in plastic flow significantly influences the fracture shape produced by damage propagation as well as affecting the localized neck.

긴장성 두통 환자 치험(治驗) 1례(例) 보고 (A Clinical Report of Tension Headache)

  • 이승희;정인철;이상룡
    • 혜화의학회지
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    • 제15권1호
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    • pp.111-115
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    • 2006
  • Tension headache is one of the most common form of headache. It may occur at any age, but is most common in adult and adolescents. One cause of this muscle contraction is a response to stress that induces changes and imbalance on autonomic nerve system. To cure tension headache, getting rid of psychological stress and anxiety have to do first. In this case, we described a 42 years old woman who diagnosed as tension headache. She complained headache with scruff pain, dyspepsia, nausea and coldness of toes. through oriental medical treatment(for example, acupuncture, herbal medicine ect.), her condition was improved.

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Wireless health monitoring of stay cable using piezoelectric strain response and smart skin technique

  • Kim, Jeong-Tae;Nguyen, Khac-Duy;Huynh, Thanh-Canh
    • Smart Structures and Systems
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    • 제12권3_4호
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    • pp.381-397
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    • 2013
  • In this paper, wireless health monitoring of stay cables using piezoelectric strain sensors and a smart skin technique is presented. For the cables, tension forces are estimated to examine their health status from vibration features with consideration of temperature effects. The following approaches are implemented to achieve the objective. Firstly, the tension force estimation utilizing the piezoelectric sensor-embedded smart skin is presented. A temperature correlation model to recalculate the tension force at a temperature of interest is designed by correlating the change in cable's dynamic features and temperature variation. Secondly, the wireless health monitoring system for stay cables is described. A piezoelectric strain sensor node and a tension force monitoring software which is embedded in the sensor are designed. Finally, the feasibility of the proposed monitoring technique is evaluated on stay cables of the Hwamyung Grand Bridge in Busan, Korea.

Effect of hybrid fibers on tension stiffening of reinforced geopolymer concrete

  • Ganesan, N.;Sahana, R.;Indira, P.V.
    • Advances in concrete construction
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    • 제5권1호
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    • pp.75-86
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    • 2017
  • An experimental work was carried out to study the effect of hybrid fiber on the tension stiffening and cracking characteristics of geopolymer concrete (GPC). A total of 24 concentrically reinforced concrete specimens were cast and tested under uniaxial tension. The grade of concrete considered was M40. The variables mainly consist of the volume fraction of crimped steel fibers (0.5 and 1.0%) and basalt fibers (0.1, 0.2 and 0.3%). The load deformation response was recorded using LVDT's. At all the stages of loading after the first cracking, crack width and crack spacing were measured. The addition of fibers in hybrid form significantly improved the tension stiffening effect. In this study, the combination of 0.5% steel fiber and 0.2% basalt fiber gave a better comparison than the other combinations.

연직축대칭(鉛直軸對稱) 부유체(浮遊體)의 동적응답(動的應答) (Dynamic Response of Vertical Axisymmetric Floating Bodies)

  • 편종근
    • 대한토목학회논문집
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    • 제4권1호
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    • pp.113-124
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    • 1984
  • 연직축대칭(鉛直軸對稱) 부유체(浮遊體)의 동적응답(動的應答)을 Fenton의 계수행렬(係數行列)을 수정(修正)하여 구(求)하여 보았다. 축대칭(軸對稱) 관계로 계산시간(計算時間)을 대폭(大幅) 줄일 수 있었으며 Hoffman의 Discus Buoy에 대한 모형실험치(模型實驗値)와 비교(比較)하였다. 앞으로 Tension Leg Platform등과 같은 대수심(大水深) 대형(大型) 구조물(構造物)의 동적응답(動的應答)을 계산(計算)하기 위한 초석(礎石)이 될 것이다.

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규칙파 중 TLP의 유탄성응답 해석 (Hydroelastic Response Analysis of TLPs in Regular Waves)

  • 하영록;이승철;구자삼
    • 동력기계공학회지
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    • 제14권2호
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    • pp.48-54
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    • 2010
  • An improved numerical scheme, to which the hydroelastic method is adapted, is introduced for predicting the motion and structural responses of tension leg platforms(TLPs) in regular waves. The numerical approach in this work is based on a combination of the three dimensional source distribution method and the finite element method. The hydrodynamic interactions among TLP members, such as columns and pontoons, are included in the motion and structural response analysis. The drag forces on the submerged slender members, which are proportional to the square of relative velocity, are included in order to estimate the responses of members with better accuracy. Comparisons with other results verify the works in this paper.

굽힘강성 변화에 따른 인장계류식 해양구조물의 동적응답 특성 (Dynamic Response Characteristics of Tension Leg Platforms with Flexibility Variations in Waves)

  • 이창호;최찬문;홍봉기
    • 수산해양기술연구
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    • 제32권2호
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    • pp.191-204
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    • 1996
  • The dynamic response characteristics with flexibility variations are examined for presenting the basic data for design of Tension Leg Platforms(TLPs)in waves. A numerical approach is based on the dynamic response analysis theory, in which the superstructure of TLPs is assumed flexible instead of the rigid body assumption used in two-step analysis method. The hydrodynamic interactions among TLP members, such as columns and pontoons are not included in the motion and structural analyse. The equations of motion of a whole structure are formulated using element-fixed coordinate systems which have the origin at the node of the each hull element.

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