• 제목/요약/키워드: Elastic joint

검색결과 356건 처리시간 0.025초

Immediate Effect of Anterior-to-posterior Talocrural Joint Mobilization with Elastic Taping on Balance Ability in Stroke Patients

  • Park, Shin-Jun;Kim, Soon-Hee
    • 대한물리의학회지
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    • 제13권3호
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    • pp.91-97
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    • 2018
  • PURPOSE: Stroke patients have reduced balance ability due to a lack of motion in the ankle joint. Elastic taping assists movement, and joint mobilization, a form of passive movement, enhances mobility. The purpose of this study was to determine the immediate effects on balance ability after anterior-to-posterior (A-P) talocrural joint mobilization combined with elastic taping in stroke patients. METHODS: Twenty stroke patients were divided into two groups: a joint mobilization with taping group (experimental group, n=10) and an elastic taping only group (control group, n=10). The experimental group underwent anteroposterior mobilization of the talus and elastic tape was applied to the calf and tibialis anterior muscles. The control group had elastic tape applied. Dynamic balanced abilities were assessed by using the BioRescue system. After 30 minutes of intervention, the forward, backward, left side, and right side sway areas ($mm^2$) were measured. RESULTS: Only the experimental group showed a significant increase in forward sway area after intervention. However, no significant differences were detected between the two groups. CONCLUSION: This study shows that A-P talocrural joint mobilization combined with elastic taping has a positive effect, producing an immediate increase in the forward balance ability of stroke patients. However, this study did not examine joint mobilization alone. In subsequent studies, it is necessary to examine the effect of joint mobilization only on balance in stroke patients.

암반터널에서의 변위파악을 위한 암반 탄성계수 추정 (Estimation of Elastic Modulus in Rock Mass for Assessing Displacment in Rock Tunnel)

  • 손무락;이소단;이원기
    • 대한토목학회논문집
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    • 제31권2C호
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    • pp.83-92
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    • 2011
  • 암반에서의 탄성계수는 암반의 변형특성을 나타내는 매우 중요한 인자로서 암반에서의 터널굴착으로 인한 내공변위를 파악하는데 이용된다. 그럼에도 불구하고 현재까지는 암석종류 및 절리특성을 반영하여 탄성계수를 산정하는 연구는 미흡한 것으로 판단된다. 따라서, 본 연구는 다양한 암석 및 절리상태에서 암반의 탄성계수를 추정하는 방법과 그 결과를 제시하고자 한다. 이를 위해서 2차원 개별요소법에 근거한 수치해석이 수행될 것이며 이를 통해 암석과 절리상태가 고려된 터널굴착 유발 내공변위가 조사될 것이다. 조사된 변위결과는 암반에서의 원형터널에 대한 탄성이론을 역이용하여 암석종류 및 절리특성이 반영된 탄성계수를 추정하는데 사용될 것이다. 본 연구를 통해 암석종류 및 절리특성을 고려하여 추정된 탄성계수는 향후 실무에서 절리가 형성된 암반터널에서의 발생변위를 파악함에 있어서 그 활용도가 매우 클 것으로 기대된다.

An Elastic Joint Manipulator for a Human friendly robot

  • Takahashi, Takayuki;Murayama, Yasushi;Wang, Zhi-Dong;Nakano, Eiji
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2001년도 ICCAS
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    • pp.44.3-44
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    • 2001
  • This articles describes a novel design elastic joint manipulator for a mobile robot, which works in an office environment with humans. The primary goal of this manipulator design is safeness on collision and contact. To achieve this, each joint is made of an elastic element and this is driver with a high ratio gear tram. The performance was verified, however, it has a serious drawback. It produce vibration, due to the elastic joints and high ratio gear train. We found that a sliding mode controller has an excellent performance for reducing such vibration. Results of computer simulation and experiments are shown.

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Seismic detailing of reinforced concrete beam-column connections

  • Kim, Jang Hoon;Mander, John B.
    • Structural Engineering and Mechanics
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    • 제10권6호
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    • pp.589-601
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    • 2000
  • A simplified analysis procedure utilizing the strut-tie modeling technique is developed to take a close look into the post-elastic deformation capacity of beam-column connections in ductile reinforced concrete frame structures. Particular emphasis is given to the effect of concrete strength decay and quantity and arrangement of joint shear steel. For this a fan-shaped crack pattern is postulated through the joints. A series of hypothetical rigid nodes are assumed through which struts, ties and boundaries are connected to each other. The equilibrium consideration enables all forces in struts, ties and boundaries to be related through the nodes. The boundary condition surrounding the joints is obtained by the mechanism analysis of the frame structures. In order to avoid a complexity from the indeterminacy of the truss model, it is assumed that all shear steel yielded. It is noted from the previous research that the capacity of struts is limited by the principal tensile strain of the joint panel for which the strain of the transverse diagonal is taken. The post-yield deformation of joint steel is taken to be the only source of the joint shear deformation beyond the elastic range. Both deformations are related by the energy consideration. The analysis is then performed by iteration for a given shear strain. The analysis results indicate that concentrating most of the joint steel near the center of the joint along with higher strength concrete may enhance the post-elastic joint performance.

엉덩관절 안쪽돌림 조절을 위한 비탄력 테이핑 방법이 엉덩관절 근활성도에 미치는 영향 -예비연구- (Effect of the Non-Elastic Taping Method of Controlling Internal Hip Joint Rotation on Hip Muscle Activity: A Preliminary Study)

  • 배송의;정주현;문동철
    • PNF and Movement
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    • 제21권3호
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    • pp.281-289
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    • 2023
  • Purpose: This study investigated the effects of the non-elastic taping method for controlling internal hip joint rotation on internal and external hip rotator muscle activity in healthy people. Methods: In this study, 18 healthy volunteers were instructed to perform the small knee bending (SKB) test. All participants completed the test following two methods (using non-elastic taping and not using taping). Muscle activation during the two methods was measured using a surface electromyography (EMG) device. Surface EMG data were collected from the gluteus medius, gluteus maximus, and tensor fasciae femoris muscles while performing the SKB test with and without non-elastic taping. Results: Muscle activity in the gluteus maximus was significantly higher during the SKB test with non-elastic taping than during the conventional SKB test with taping (p < 0.05). Tensor fasciae latae muscle activity was lower during the SKB test with non-elastic taping than during the conventional SKB test (p < 0.05). Conclusion: The findings suggest that the non-elastic taping method for controlling internal hip joint rotation effectively activates the hip's external rotator muscles and minimizes unwanted internal rotator muscle use during the SKB test. Therefore, the non-elastic taping method for controlling internal hip joint rotation could be an effective intervention for those who cannot control the internal rotation of their hips.

암석 및 절리특성을 고려한 암반의 탄성계수 추정에 관한 수치해석적 연구 (Study on Numerical Analysis of Estimating Elastic Modulus in Rockmass with a Consideration of Rock and Joint Characteristcs)

  • 손무락;이원기
    • 대한토목학회논문집
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    • 제33권1호
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    • pp.229-239
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    • 2013
  • 암반에서의 탄성계수는 암반의 변형특성을 나타내는 매우 중요한 인자로서 암반에서의 터널굴착 또는 다른 활동 등으로 인해 발생되는 변위를 파악하는데 자주 이용된다. 그럼에도 불구하고 현재까지는 암석종류 및 절리특성을 반영하여 탄성계수를 산정하는 연구는 미흡한 것으로 판단된다. 따라서, 본 연구는 다양한 암석 및 절리상태에서 암반의 탄성계수를 추정하고자 한다. 이를 위해서 암석상태 및 절리특성을 고려한 수치해석 매개변수 연구를 수행하고, 조사된 변위결과를 통해 암반에서의 원형터널에 대한 탄성이론을 역이용하여 암석종류 및 절리특성이 반영된 탄성계수를 추정하는데 사용될 것이다. 본 연구를 통해 얻어진 결과는 절리가 형성된 암반에서 터널굴착 또는 다른 활동 등으로 인해 발생되는 변위를 파악함에 있어서 그 활용도가 매우 클 것으로 기대된다.

비탄력 테이핑이 슬개대퇴관절 통증증후군 환자의 슬개건 통증과 슬관절부 근력, 보행에 미치는 영향 비교 (Comparison of the Effects of Non-elastic Taping on Patellar tendon Pain, Knee Muscle Strength and Gait in Patients with Patellofemoral Joint Pain Syndrome)

  • 정상모;정영준;안승원
    • 대한정형도수물리치료학회지
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    • 제25권2호
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    • pp.39-46
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    • 2019
  • Background: Ground repulsion or impact on the ground during daily activities, sports, or occupational activities may cause injury to the knee when walking. Non-elastic taping is effective in treating these problems in previous studies. Non-elastic taping strengthens the structure of the soft tissues of the injured knee joint to maintain constant tension, improves muscle rearrangement and function, and improves proprioception. Based on previous studies, we intended to see the therapeutic changes of non-elastic taping in patients with patellofemoral joint pain syndrome. Methods: The non-elastic taping application method was applied to the patient three times for five hours for one week. Non-elastic taping was applied to the patellar tendon with little space above the skin segment of the patellar femur, with both sides fixed by taping. Muscle strength and gait change were evaluated with non-elastc taping. Results: The knee flexion, extension strength and gait evaluation of the knee joint with inelastic taping showed significant differences after treatment. There was a significant difference in the comparison between the two groups after the treatment method was applied (p<.05). Conclusion: As a result, this study confirms that the non-elastic taping method applied for the treatment of patellar femoral joint pain syndrome is effective in the treatment.

터널 굴착하중 조건에서의 절리암반의 탄성계수 예측 (Estimation of Elastic Modulus of Jointed Rock Mass under Tunnel Excavation Loading)

  • 손무락;이원기;황영철
    • 한국지반공학회논문집
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    • 제30권7호
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    • pp.17-26
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    • 2014
  • 절리를 포함한 암반에서 터널굴착시 발생하는 내공변위는 터널의 안정성과 필요 확보공간 및 시공성을 위해서 매우 중요한 인자이다. 터널굴착시 발생할 수 있는 내공변위의 크기는 탄성계수가 큰 영향을 미치는 인자이며 특히 절리면이 터널거동을 지배하는 암반에서는 신뢰성 있는 절리암반의 탄성계수를 산정하는 것은 매우 중요하다. 절리암반의 탄성계수는 암석종류, 절리조건, 하중조건 등과 같은 많은 인자에 의해서 영향을 받는다. 그럼에도 불구하고 기존의 대부분의 연구는 암석 및 절리, 터널 굴착하중 조건 등을 체계적으로 고려하지 않고 압축하중 조건에 근거한 대략적인 경험식에 초점을 두고 있다. 그러므로 본 연구에서는 터널 굴착하중 조건에서의 절리암반의 탄성계수를 보다 합리적으로 추정하기 위하여 암석 및 절리조건을 체계적으로 고려하였다. 본 연구에서는 암석종류, 절리전단강도, 절리경사각, 절리군의 수 및 절리간격을 해석인자로서 고려하였다. 다양한 암석 및 절리조건을 고려하여 수치해석적 매개변수 연구를 수행하였고, 그 결과를 기존의 경험적인 방법들과 비교분석하였으며, 다양한 암석 및 절리조건에서의 탄성계수에 대한 변화도표를 제시하였다. 본 연구를 통해 얻어진 결과는 절리암반에서 터널굴착으로 인해 발생되는 터널 내공변위를 파악하는데 실무적으로 활용될 수 있을 것으로 기대된다.

Preliminary numerical study on long-wavelength wave propagation in a jointed rock mass

  • Chong, Song-Hun;Kim, Ji-Won;Cho, Gye-Chun;Song, Ki-Il
    • Geomechanics and Engineering
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    • 제21권3호
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    • pp.227-236
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    • 2020
  • Non-destructive exploration using elastic waves has been widely used to characterize rock mass properties. Wave propagation in jointed rock masses is significantly governed by the characteristics and orientation of discontinuities. The relationship between spatial heterogeneity (i.e., joint spacing) and wavelength for elastic waves propagating through jointed rock masses have been investigated previously. Discontinuous rock masses can be considered as an equivalent continuum material when the wavelength of the propagating elastic wave exceeds the spatial heterogeneity. However, it is unclear how stress-dependent long-wavelength elastic waves propagate through a repetitive rock-joint system with multiple joints. A preliminary numerical simulation was performed in in this study to investigate long-wavelength elastic wave propagation in regularly jointed rock masses using the three-dimensional distinct element code program. First, experimental studies using the quasi-static resonant column (QSRC) testing device are performed on regularly jointed disc column specimens for three different materials (acetal, aluminum, and gneiss). The P- and S-wave velocities of the specimens are obtained under various normal stress levels. The normal and shear joint stiffness are calculated from the experimental results using an equivalent continuum model and used as input parameters for numerical analysis. The spatial and temporal sizes are carefully selected to guarantee a stable numerical simulation. Based on the calibrated jointed rock model, the numerical and experimental results are compared.

이종재료 금속조인트의 굽힘에 의한 잔류응력 해석 (Residual Stress Analysis in Bi-material Metal Joint under Bending Moment by Finite Element Method)

  • 백태현;정걸;박태근
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2005년도 추계학술대회 논문집
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    • pp.448-451
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    • 2005
  • It was observed that after unloading or removal of the load from the specimen subjected to bending stress, partial or full elastic spring back occurred and considerable stresses have resulted while plastic deformation was considered. ABAQUS is a suite of powerful engineering simulation programs, based on the finite element method. In this paper, it was used as the main tool to analyze elastic and plastic deformations of hi-material metal joint. In the case of elastic deformations, the results were comparable to the theoretical data. Plastic deformations and residual stresses of hi-material metal joint under bending moment were obtained by ABAQUS; where the theory needs to be studied and improved further to verify the results.

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