• 제목/요약/키워드: tension relaxation

검색결과 217건 처리시간 0.025초

막구조의 초기형상 및 재단도 결정알고리즘에 관한 연구 (A Study on the Shape Finding and Patterning Procedures for Membrane Structures)

  • 한상을;이경수;이상주;유용주
    • 한국전산구조공학회:학술대회논문집
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    • 한국전산구조공학회 1998년도 가을 학술발표회 논문집
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    • pp.298-305
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    • 1998
  • The purpose of this study is to propose the method of determining the initial fabric membrane structures surface and membrane patterning procedures. Tension structure, such as, fabric membrane structures and cable-net, is stabilized by their initial prestress and boundary condition. The process to find initial structural overall shape of tension structures produced by initial prestress called Shape Finding or Shape Analysis. One of the most important factor for the design of membrane structures is to search initial smooth surface, because unlike steel or concrete building elements which resist loads in bending, all tension structure forces are carried within the surface by membrane stress or cable tension. To obtain initial surface of fabric membrane element in large deformation analysis, the membrane element is idealized as cable using a technique with Force-density method. and that result is compared with well-known nonlinear numerical method, such as Newton-raphson method and Dynamic relaxation method. The shape resulting from Force-density method has been dealt with as the initial membrane shape and used patterning procedures.

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세도우 마스크 장력에 열공정이 미치는 영향 (Effect of Heat Treatment Process on the Shadow Mask Tension)

  • 현도익;문영훈;조종래
    • 소성∙가공
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    • 제12권5호
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    • pp.487-492
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    • 2003
  • Tension variations with heat treatment in shadow mask for flat braun tubes are investigated in this study. In CRT, landing shift of the electron beam due to thermal deformation of the tension mask made the color purity of screen worse. In order to get the final results of thermal deformation, the tensile force within the mask and the welding processes between the rail and the extended mask have to be analysed sequentially. In this study, the effect of heat treatment is studied in terms of tension variations of shadow mask during its manufacturing process.

점진적(漸進的) 근육이완법(筋肉弛緩法)이 자율신경계(自律神經系)에 미치는 영향(影響) (The Effect of Progressive Muscle Relaxation Therapy on Autonomic Nerve System)

  • 이재혁;이제균
    • 동의신경정신과학회지
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    • 제18권1호
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    • pp.111-122
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    • 2007
  • Objective : Progressive muscle relaxation(PMR) therapy is the way of mind and body self-regulation which makes major muscles tension to be comfortable condition. It was considered to be important to check the level of relaxation in objective validity. Therefore, Heart rate variability(HRV) is the valuable measurement to investigate the effect of progressive muscle relaxation therapy on autonomic nerve system. Method : I studied 38 subjects. The subjects were measured HRV at first. And then, Using a CD player, the subjects listened to recorded PMR program for 15 minutes. After this progress, I rechecked HRV. Results : heart rate item of HRV was significantly decreased. Also, the numerical value of SDNN(standard deviation of all NN intervals) and SDSD(standard deviation of differences between adjacent NN intervals) items of HRV were showed significantly increased in all subjects after PMR. Conclusion : It indicated that PMR is efficient for inspiring resistance of the stress and a sense of stability, and PMR is a valuable method to reduce the mind stress and stiffness of body muscle.

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Geodesic shape finding of membrane structure with geodesic string by the dynamic relaxation method

  • Lee, K.S.;Han, S.E.
    • Structural Engineering and Mechanics
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    • 제39권1호
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    • pp.93-113
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    • 2011
  • The explicit nonlinear dynamic relaxation method (DRM) is applied to the nonlinear geodesic shape finding analysis by introducing fictional tensioned 'strings' along the desired seams with a three or four-node membrane element. A number of results from the numerical example for the nonlinear geodesic shape finding and patterning analysis are obtained by the proposed method to demonstrate the accuracy and efficiency of the developed method. Therefore, the proposed geodesic shape finding algorithm may improve the applicability of a four-node membrane element to membrane structural engineering and design analysis simultaneously for the shape finding, stress, and patterning analysis.

긴장성 근육통 증후군으로 인한 만성 경항통 환자에 대한 이완 요법 적용 1례(例) (The Report on Relaxation Therapy Application for Chronic Neck Pain with Tension Myositis Syndrome Trend)

  • 김규태;권승로;송주현;김수용;이제균
    • 동의신경정신과학회지
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    • 제16권2호
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    • pp.277-285
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    • 2005
  • 2005년 5월 자생한방병원 한방신경정신과에 입원한 환자에 대하여 긴장성 근육통 증후군의 관점에서의 접근을 통해 이완 요법치료를 실시하여 환자 동통 치료에 대하여 양호한 결과를 보였고 환자의 통증 회복 의지에 대한 심리 상태에도 변화가 있었다. 그 결과 다음과 같은 소견을 보였다. 1. 기질적인 원인이 있는 만성 경항부 통증 환자에서 환자의 심리적 상태를 고려한 이완요법을 병행하여 통증 지각 감소와 심리적 자신감 회복에 양호한 결과를 보였다. 2. 긴장성 근육통 증후군에서의 환자의 내재되어 있는 심리상태가 통증을 일으킨다고 보는 관점은 한의학적 관점에서는 기(氣)의 순환 장애에서 오는 기통증(氣痛症), 기울증(氣鬱症)으로 볼 수 있으며, 이완 요법은 환자 치료에 정서, 심리적인 측면을 고려한 점에서 이정변기요법(移精變氣療法)등과 같은 한방정신요법과 유사성을 찾아 볼 수 있다. 3. 이완 요법은 통증 치료에 있어서 심리적 이완, 안정을 도모하고, 통증에 대한 과도한 관심을 억제하여 통증 지각 완화에 도움이 된다.

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Torque Shear형 고장력 볼트 이음부의 피로거동에 관한 실험적 연구 (An Experimental Study on the Fatigue Behavior of Torque Shear Type High Tension Bolted Joints)

  • 장동일;이성욱
    • 한국강구조학회 논문집
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    • 제8권3호통권28호
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    • pp.151-160
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    • 1996
  • The fatigue test under the constant amplitude repeated loading is performed to investigate the fatigue behavior of the Torque Shear type high tension bolted joint which is able to manage the axial force uniformly. From the test results, it's known that the reduction of the axial force of T/S bolt followed by the elasped time is similar to that of the high tension bolts. The difference of relaxation is not occurred according to the position of bolts, the size of the introduced axial force but the effect of the variation of temperature is large. In the reduction of the axial force followed by the cumulation of the fatigue load, the outer bolt is larger than the inner bolt. This result depends on the difference in the distribution of the non-slip zone. The variation of the surface roughness affects the slip and the reduction of the anal force.

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흰쥐에서 Cumambrin A의 대동맥 이완작용 (Effect of Cumambrin A on the Relaxation of Rat Aorta)

  • 홍용근;양민석;박윤배
    • 생약학회지
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    • 제36권1호통권140호
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    • pp.17-20
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    • 2005
  • We previously reported that the exogenous administration of cumambrin A, a sesquiterpene lactone from the dried flowers of Chrysanthemum boreale Makino has a pharmacological effect on normalization of blood pressure in the spontaneously hypertensive rats (SHR). In the present study, we further investigated the effect of cumambrin A on the relaxation of phenylephrine-induced precontracted rat aortic artery rings. The potency of cumambrin A was than compared to verapamil, a well known $Ca^{2+}-channel$ blocker. The results demonstrate that the isolated rat aortic arteries are relaxed to basal tension at a concentration of $5{\times}10^{-5}\;M$ cumambrin A treatment. The results also show that the phenylephrine-induced contraction is inhibited by a pretreatment of cumambrin A. Co-treatment of cumambrin A and verapamil showed a strong synergetic effect on the relaxation of rat aortic artery rings. Thus, these data demonstrate that cumambrin A is a potent relaxant of rat aortic smooth muscle and suggest that cumambrin A modulates intracellular or extracellular $Ca^{2+}$ mobilization.

가속화 시험을 통한 금속 밀봉재 장기성능 평가 (Evaluation of Long-term Performance of Metal Seal Through Accelerated Test)

  • 최우석;임종민;양윤영;조상순
    • 방사성폐기물학회지
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    • 제18권2_spc호
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    • pp.237-245
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    • 2020
  • 사용후핵연료를 저장하는 볼트체결 저장용기의 격납경계를 형성하는 주된 구성요소는 금속 밀봉재이다. 이러한 금속 밀봉재는 열과 방사선에 의해 그 성질이 저하된다. 또한, 금속 밀봉재가 강한 열에 장기간 노출되면 크리프 현상이 발생한다. 이러한 크리프는 밀봉시스템에 응력 이완을 가져와서, 결국 밀봉재의 건전성을 해치게 된다. 이러한 응력 이완은 금속 밀봉재의 밀봉성능 저하로 이어지며, 저하의 정도에 따라 저장용기의 누설을 야기할 수 있다. 또한, 볼트 체결력의 감소도 밀봉성능 저하에 영향을 미친다. 본 논문에서는 금속 밀봉재의 격납건전성과 볼트체결력 감소를 평가하기 위해 수행한 가속화 시험의 결과에 대하여 기술한다. 전 시험기간 동안 각 시편에서의 누설률, 볼트 변형률, 금속 밀봉재 주변 온도를 계측하여 분석하였고, 금속 밀봉재는 저장기간 50년 동안 격납건전성을 유지함을 입증하였다. 또한, 가속화 시험의 타당성에 대해서 기술하였다.

기니 픽 장관 평활근에서 Sodium Nitroprusside가 장력에 미치는 영향 (The Eeffect of Sodium Nitroprusside on Muscle Tension in Guinea-pig Ileum)

  • 권성춘;김시연;김은주;강복순
    • The Korean Journal of Physiology and Pharmacology
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    • 제1권6호
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    • pp.797-808
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    • 1997
  • Nitric oxide (NO) has been 3mown as a mediator of nonadrenergic, noncholinergic inhibitory neurotransmitter in intestinal smooth muscles. It has been suggested that NO donor such as sodium nitroprusside (SNP) produces relaxation of smooth muscle via activation of guanylate cyclase and elevation of cGMP levels. We have therefore investigated the effects of NO, using SNP, on muscle tension in the longitudinal smooth muscle of guinea-pig ileum. The possible role of cGMP was also investigated as well as the involvement of $K^+$ channel on SNP-induced inhibitory effect. The results are summarized as follows; high KCI-or CCh-activated contractions were inhibited by SNP in a concentration-dependent manner. 8-Br-cGMP also showed a similar effect in that of SNP TEA (1 mM) significantly reduced the SNP-induced inhibitory effect. SNP-induced effect was forther reduced by the presence of 10 mM TEA. On the other hand, 4-AP (0.1 mM), glibenclamide $(10\;{\mu}M)$ and apinain $(0.1\;{\mu}M)$ showed little effects on SNP-induced relaxation. Zaprinast significantly potentiated the SNP-induced inhibitory effect in all ranges. ODQ also significantly decreased the SNP-induced inhibitory effect. Pretreatment with CPA $(10\;{\mu}M)$ slightly reduced the SNP-induced inhibitory effect. From the above results, both effect mediated by NO and cGMP might be responsible for the activation of $Ca^{2+}$-activated $K^+$ channel by SNP in guinea-rig ileum. And this $K^+$ channel activation by SNP also contributes to the SNP-induced membrane hyperpolarization and relaxation.

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강활(羌活)이 가토(家兎) 혈관평골근(家兎 血管平滑筋)의 긴장성(緊張性) 조절(調節)에 미치는 영향(影響) (The Effects of Notopterygii Rhizoma on the Carotid Arterial Tension in Rabbit)

  • 장규태;김장현
    • 대한한방소아과학회지
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    • 제12권1호
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    • pp.163-181
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    • 1998
  • The purpose of this study was to analyze the Rhizoma on the blood pressure, heart rate and to define the mechanism of Notopterygii Rhizoma-induced relaxation in rabbit common carotid arterial contracted by agonists. Method : In order to explore the effect of Notopterygii Rhizoma on the blood pressure and heart rate, Notopterygii Rhizoma extract was injected in vein of rabbit ear. In order to investigate the effect of Notopterygii Rhizoma on norepinephrine(NE)-induced contracted rabbit carotid arterial strips, transverse strips with intact or damaged endothelium were used for the experiment using organ bath. To analyze the mechanism of Notopterygii Rhizoma-induced relaxation, Notopterygii Rhizoma extract infused into NE-induced contracted strips induced by agonists after treatment of methylene blue, propranolol, ouabain and it infused into serotonin, potassium chloride-induced contracted strips. Result : The blood pressure was significantly decreased by Notopterygii Rhizoma, but heart rate was insignificantly. In addition, Notopterygii Rhizoma significantly relaxed the norepinephrine, serotonin, potassium-induced contracted strips with intact endothelium or damaged endothelium. The relaxing effect of Notopterygii Rhizoma In NE-induced contracted strips with damaged endothelium by pretreatment of methylene blue, propranolol was not changed, but Ouabain was significantly decreased. Conclusion : These results were shown that Notopterygii Rhizoma affected the NE -induced contracted smooth muscle without the participation of endothelium, and demonstrated that the mechanism of NotoDtervgii Rhizoma-induced relaxation was the obstruction of receptor-operated Ca2+ channel.

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