• 제목/요약/키워드: Elastic Support

검색결과 305건 처리시간 0.024초

Pile과 지반특성을 고려한 기초구조물의 거동해석 (Analysis far Behavior of Substructure Considering Characteristics of Pile and Soil)

  • 안주옥;공천석;정영묵;임정열
    • 한국전산구조공학회:학술대회논문집
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    • 한국전산구조공학회 2000년도 봄 학술발표회논문집
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    • pp.253-259
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    • 2000
  • This thesis investigated the behavior of super structure by varying the factors such as the change of pile rigidity, the characteristics of soil and the constraint condition of support. The results of this study are as follows; 1. The pile rigidity in the Fig 3.3 computed by the rotating deformed plane method becomes the elastic range at approximately about 5.1 m (D : 1.0 m) below the ground level. This result is consistent with the previous study that the pile deformation occurs approximately 3 to 6 times pile diameter from the pile head. 2. The values of forces and deformations for the structure-pile system in Y-direction appeared larger than that in X-direction, since the pile rigidity and constraint condition of support were changed as shown Fig.3.5 to 3.8. 3. The current practice for the analysis of structure-pile system has not considered the variation of pile rigidity and the constraint condition of support. So, the analysis of structure-pile system with large difference in super-structure rigidity must includes these factors in both X and Y directions.

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탄성밴드를 이용한 저항운동이 회전근개봉합술 환자의 견관절가동범위와 기능 및 통증에 미치는 효과 (Effects of Resistance Exercise using Elastic Band on Range of Motion, Function and Shoulder Pain among Patients with Rotator Cuff Repair)

  • 심재옥
    • 성인간호학회지
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    • 제28권5호
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    • pp.491-500
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    • 2016
  • Purpose: The purpose of this study was to examine the effect of resistive exercise using an elastic band on range of motion, function and shoulder pain. Methods: Forty two subjects who had rotator cuff surgery were assigned either to a treatment or a comparison group, twenty one each. Following a six week period after surgery those in the treatment group participated in resistant exercise using an elastic band for four weeks. The subjects in the comparison group did not participate in the exercise program. The goniometer measured range of motion, a modified tool measured function, and a self report numerical rating scale measured pain. The data were analyzed using $x^2$ test, Fisher's exact, t-test and the Mann-Whitney Test. Results: Although not statistically significant, there was a trend that more subjects in the treatment group had increased range of motion. There was a statistically significance among the treatment group in terms of increased function (p=.015). Further the treatment group reported less pain that those in the comparison group (p<.001). Conclusion: The findings support that resistance exercise is an effective strategy for patients with rotator cuff repair.

Elastic distortional buckling of tapered composite beams

  • Bradford, M.A.;Ronagh, H.R.
    • Structural Engineering and Mechanics
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    • 제5권3호
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    • pp.269-281
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    • 1997
  • The overall buckling mode in a composite steel-concrete beam over an internal support is necessarily lateral-distortional, in which the bottom compressive range displaces laterally and twists, since the top flange is restrained by the nearly rigid concrete slab. An efficient finite element method is used to study elastic lateral-distortional buckling in composite beams whose steel portion is tapered. The simplified model for a continuous beam that is presented herein is a fixed ended cantilever whose steel portion is tapered, and is subjected to moment gradient. This is intended to give an insight into distortion in a continuous beam that occurs in the negative bending region, and the differences between the cantilever representation and the continuous beam are highlighted. An eigenproblem is established, and the buckling modes and loads are determined in the elastic range of structural response. It is found from the finite element study that the buckling moment may be enhanced significantly by using a vertical stiffener in the region where the lateral movement of the bottom range is greatest. This enhancement is quantified in the paper.

최저대역보장형 서비스에 대한 과금 (Charging the Assured-Bandwidth Service)

  • Seok, Seung-Hak;Lee, Hoon;Lee, Kwang-Hui
    • 대한전자공학회논문지TC
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    • 제41권3호
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    • pp.21-28
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    • 2004
  • 가까운 미래에 우리는 기존의 정액제 요금에서 종량제가 첨가되는 것과 같은 인터넷서비스의 요금체계에 변화를 맞이할 것이다. 본 논문은 이와 같은 움직임에 대비하여 차세대 네트워크에서 서비스품질이 보장되는 인터넷 서비스에 대한 사용량기반의 과금체계를 제안하고자 한다. 먼저, IP 네트워크에서 가장 주류를 이룰 Assured service에 의해서 발생되는 적응성이 있는 트래픽의 특성을 살펴보고, 이어서 네트워크 대역의 사용량에 기반한 과금방안을 제안한다. 그리고, 어떤 형태의 Assured service에도 적용 가능한 과금함수를 제안하고, 간단한 수치계산을 통하여 제안하는 방법의 유효성에 대하여 기술한다.

Static and dynamic analysis of cable-suspended concrete beams

  • Kumar, Pankaj;Ganguli, Abhijit;Benipal, Gurmail
    • Structural Engineering and Mechanics
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    • 제64권5호
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    • pp.611-620
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    • 2017
  • A new theory of weightless sagging planer elasto-flexible cables under point loads is developed earlier by the authors and used for predicting the nonlinear dynamic response of cable-suspended linear elastic beams. However, this theory is not valid for nonlinear elastic cracked concrete beams possessing different positive and negative flexural rigidity. In the present paper, the flexural response of simply supported cracked concrete beams suspended from cables by two hangers is presented. Following a procedure established earlier, rate-type constitutive equations and third order nonlinear differential equations of motion for the structures undergoing small elastic displacements are derived. Upon general quasi-static loading, negative nodal forces, moments and support reactions may be introduced in the cable-suspended concrete beams and linear modal frequencies may abruptly change. Subharmonic resonances are predicted under harmonic loading. Uncoupling of the nodal response is proposed as a more general criterion of crossover phenomenon. Significance of the bilinearity ratio of the concrete beam and elasto-configurational displacements of the cable for the structural response is brought out. The relevance of the proposed theory for the analysis and the design of the cable-suspended bridges is critically evaluated.

수정된 선형계획법을 이용한 다물체 탄성 접촉 문제 해석 (Multibody Elastic Contact Analysis by Modified Linear Programming)

  • 이대희;전범준;최동훈;임장근;윤갑영
    • 대한기계학회논문집
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    • 제13권1호
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    • pp.1-8
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    • 1989
  • 본 연구에서는 마찰을 무시할 수 있는 경우의 일반적인 다물체 탄성 접촉 문제를 수식화하고 이를 최적화 문제로 변환한 후 수정된 선형 계획법을 이용하여 임의 형상의 다물체간의 접촉 문제를 해석할 수 있는 산법을 제시하였다.

3차원 케이블망의 초기평형상태 결정 및 정적 비선형 유한요소해석 (Static Non-linear Finite Element Analysis of Spatial Cable Networks)

  • 김문영;김남일;안상섭
    • 전산구조공학
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    • 제11권1호
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    • pp.179-190
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    • 1998
  • 두개의 케이블요소를 이용한 3차원 케이블망의 정적 비선형 유한요소해석기법을 제시한다. 먼저, 공간 트러스요소와 탄성현수선 케이블요소(elastic catenary cable element)의 접선강도행렬과 질량행렬을 유도하는 과정을 간략히 요약한다. 지점 변위를 일으키고 자중을 받는 케이블망의 초기평형 상태를 결정하기 위하여, Newton-Raphson 반복법에 근거한 하중증분법과 현수케이블요소를 적용하는 경우에 viscous damping을 고려한 dynamic relaxation법을 제시한다. 또한 초기의 정적평형상태를 기준으로 추가하중에 대한 케이블망의 정적 비선형해석을 수행한다. 지점변위와 외력을 받는 케이블 구조에 대하여 비선형해석을 수행하고, 해석결과들을 기존의 문헌의 결과와 비교, 검토하므로써 본 논문에서 제시한 이론 및 해석방법의 타당성을 입증한다.

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Rheology of flocculated kaolinite dispersions

  • McFarlane A.J.;Addai-Mensah J.;Bremmell K.
    • Korea-Australia Rheology Journal
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    • 제17권4호
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    • pp.181-190
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    • 2005
  • Rheological characterisation of flocculated kaolinite pulps has been undertaken to elucidate particle interactions underpinning the dewatering behaviour induced by flocculation with polyethylene oxide (PEO), anionic polyacrylamide (PAM A) and their blends. Shear yield stress $(\tau_y)$ analysis indicated that polymer mediated particle interactions were markedly amplified upon shear of PEG based pulps. In contrast, PAM A based pulps showed a significant decrease in yield values upon shear. Steady stress measurements analysed using a modified Ellis model indicated subtle differences between the respective linear viscoelastic plateaus of the pulps. Furthermore, modified shear thinning behaviour was evident in PEG based pulps. Estimation of elastic and viscous moduli (G', G') was made using dynamic stress analysis for comparison with values determined from vane measurements. Despite a noticeable difference in the magnitude of G' between the two methods, similar trends indicating sheared PEG-based pulps to be more elastic than PAM based pulps, were observed. Floc microstructural observations obtained in support of rheological properties indicate that PEG flocculant induces significantly more compact particle aggregation within the clay pulps under shear consistent with the yield stress data, in contrast to PAM A, or indeed unsheared PEG based pulps. Consequentially, sheared PEG based pulps show significantly improved dewatering behaviour. The implications of the results, potential benefits and drawbacks of flocculation with PEG and PAM A are discussed with respect to improvements in current dewatering processes used in the minerals industry.

Protection of a Multicast Connection Request in an Elastic Optical Network Using Shared Protection

  • BODJRE, Aka Hugues Felix;ADEPO, Joel;COULIBALY, Adama;BABRI, Michel
    • International Journal of Computer Science & Network Security
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    • 제21권1호
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    • pp.119-124
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    • 2021
  • Elastic Optical Networks (EONs) allow to solve the high demand for bandwidth due to the increase in the number of internet users and the explosion of multicast applications. To support multicast applications, network operator computes a tree-shaped path, which is a set of optical channels. Generally, the demand for bandwidth on an optical channel is enormous so that, if there is a single fiber failure, it could cause a serious interruption in data transmission and a huge loss of data. To avoid serious interruption in data transmission, the tree-shaped path of a multicast connection may be protected. Several works have been proposed methods to do this. But these works may cause the duplication of some resources after recovery due to a link failure. Therefore, this duplication can lead to inefficient use of network resources. Our work consists to propose a method of protection that eliminates the link that causes duplication so that, the final backup path structure after link failure is a tree. Evaluations and analyses have shown that our method uses less backup resources than methods for protection of a multicast connection.

The effect of gait training with an elastic ankle-foot orthosis on balance and walking ability of persons with chronic stroke: a randomized controlled trial

  • Chi, Ming Hao;Yim, Jong Eun;Yi, Dong hyun
    • Physical Therapy Rehabilitation Science
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    • 제9권4호
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    • pp.222-229
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    • 2020
  • Objective: The purpose of this study was to investigate the effect of treadmill exercise on the posture and walking speed of chronic stroke survivors with an ankle-foot orthosis. Design: Randomized controlled trial. Methods: Twenty-four chronic persons with chronic stroke admitted to Bobath Memorial Hospital in Seongnam city were divided into two groups by random blind method. Treadmill exercise with an elastic ankle-foot orthosis was performed in the experimental group and treadmill exercise was performed in the control group. The experiment was carried out for 6 weeks, and the experiment was carried out three times a week for 20 minutes per session. To measure the effect, static balance was measured using the MTD system before and after training, and the Berg Balance Scale (BBS) was used to measure functional balance. Results: There was a statistically significant difference between the 2 groups in the BBS measurement results for confirming the functional balance (p<0.05). Also, there was a significant difference between the 2 groups in single limb support time, step time and step length (p<0.05). Conclusions: In this study, it was found that treadmill exercise with an elastic ankle-foot orthosis in persons with chronic stroke was effective in maintaining functional balance, walking ability, step length, and step time. Therefore, it is necessary to use a flexible ankle-foot orthosis with proper treadmill exercise as a method of improving balance and walking speed of chronic stroke survivors.