• Journal of Mechanical Science and Technology
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• v.19 no.9
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• pp.1761-1772
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• 2005

In blood flow passing through the mechanical heart valve (MHV) and elastic blood vessel, hemolysis and platelet activation causing thrombus formation can be seen owing to the shear stress in the blood. Also, fracture and deformation of leaflets can be observed depending on the shape and material properties of the leaflets which is opened and closed in a cycle. Hence, comprehensive study is needed on the hemodynamics which is associated with the motion of leaflet and elastic blood vessel in terms of fluid-structure interaction. In this paper, a numerical analysis has been performed for a three-dimensional pulsatile blood flow associated with the elastic blood vessel and curved bileaflet for multiple cycles in light of fluid-structure interaction. From this analysis fluttering phenomenon and rebound of the leaflet have been observed and recirculation and regurgitation have been found in the flow fields of the blood. Also, the pressure distribution and the radial displacement of the elastic blood vessel have been obtained. The motion of the leaflet and flow fields of the blood have shown similar tendency compared with the previous experiments carried out in other studies. The present study can contribute to the design methodology for the curved bileaflet mechanical heart valve. Furthermore, the proposed fluid-structure interaction method will be effectively used in various fields where the interaction between fluid flow and structure are involved.

• Structural Engineering and Mechanics
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• v.24 no.1
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• pp.51-62
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• 2006

Differential transform method (DTM) for free vibration analysis of both ends simply supported beam resting on elastic foundation is suggested. The fourth order partial differential equation for free vibration of the beam resting on elastic foundation subjected to bending moment, shear and axial compressive load is obtained by using Winkler hypothesis and small displacement theory. It is assumed that the material is linear-elastic, and that axial load and modulus of subgrade reaction to be constant. In the analysis, shear and axial load effects are considered. The frequency factors of the beam are calculated by using DTM due to the values of relative stiffness; the results are presented in graphs and tables.

• Korean Journal of Adult Nursing
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• v.28 no.5
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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.

• Journal of the Korean Society of Safety
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• v.20 no.3 s.71
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• pp.143-151
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• 2005

In this study, it is demonstrated that how the effect of the Near Fault Ground Motion affects the response of the structure. Considering the general characteristic of Near Fault Ground Motion the characteristics of Near Fault Ground Motions is analysed by elastic response spectrums, and the inelastic response spectrum is evaluated with the ductility and the yield strength to consider the inelastic behavior which couldn't be simulated through the elastic response spectrum. The result of this study shows that the effect of Near Fault Ground Motion should be considered in the long period range of long span structures but the domestic seismic design code was developed based on Far Fault Ground Motions, so the effects of Near Fault Ground Motions, which is very serious especially in large structures with a long period, are not considered. Therefore, the effect of the Near Fault Ground Motion has to be examined especially in the seismic performance evaluation of long period structure.

• Journal of Korean Clinical Nursing Research
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• v.21 no.2
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• pp.266-275
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• 2015

Purpose: The objective of this study was to verify the effects of elastic-band exercise on pain, range of motion, and fear of falling in patients with total knee replacement. Methods: The study design was a nonequivalent control group non-synchronized quasi-experimental design. Data were collected from December 10, 2014 to January 10, 2015 in an orthopedic specialty hospital located in the C city. Forty-eight patients participated in the study, and each twenty-four were assigned to the experimental group and the control group. The elastic-band exercise was used with the experimental group for 10 days. The numeric rating scale was used to measure pain, goniometer to measure range of motion, and a questionnaire to measure fear of falling. The data were analyzed using $x^2-test$, Fisher's exact, t-test and paired t-test. Results: Compared to the control group, pain in the experimental group decreased (t=-2.89, p=.006), range of motion increased (t=2.98, p=.005), and fear of falling decreased (t=-4.63 p<.001). Conclusion: The elastic-band exercise for total knee replacement patients is considered to be an effective nursing intervention to decrease pain and fear of falling, and to increase range of motion.

• Journal of computational fluids engineering
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• v.17 no.2
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• pp.107-112
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• 2012

We explored the dynamic motions and the lateral equilibrium positions of an elastic capsule in channel flow at moderate Reynolds number varying Re, aspect ratio, size ratio, membrane stretching and bending coefficient. The transition of tank-treading/swinging to tumbling motion was observed in the simulations and the transition of dynamic motions for capsules resulted in different trend of the variation in the lateral equilibrium positions. Though other conditions were similar, the capsule with tumbling motion migrated closer to the wall than that with tank-treading motion.

• Journal of the Korean Society of Physical Medicine
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• v.12 no.4
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• pp.1-9
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• 2017

PURPOSE: This study investigated the effect that an elastic therapeutic taping treatment given to patients with chronic ankle instability had on the vertical ground reaction force, center of pressure, and range of motion in the ankle, knee and hip joints, during a Cross-cutting movement from landing. METHODS: This study analyzed 12 able-bodied adults and 12 patients with chronic ankle instability classified by using the Cumberland tool in the motion analysis laboratory, Hanseo University. The experiment was conducted under two conditions elastic taping and no treatment. In order to analyze the difference between the groups. An independent t-test was performed at p>.01. RESULTS: Plying an elastic therapeutic taping to the patients with chronic ankle instability significantly decreased the range of joint motion in the inversion of the ankle joint, the flexion of the knee joint, and the flexion and internal rotation of the hip joint during a cross-cutting movement from landing in comparison with the able-bodied adults p<.01. This restriction in the range of motion decreased the center-of-pressure trajectory length of patients with chronic ankle instability p>.01. CONCLUSION: An elastic therapeutic taping treatment given to patients with chronic ankle instability causes ankle stability to increase during a cross-cutting movement from landing.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.26 no.2A
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• pp.273-284
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• 2006

In this study, After considering the general characteristic of Near Fault Ground Motion, the inelastic response spectrum is made to evaluate using the change of ductility and yield stiffness coefficient according to the inelastic behavior of structures which couldn't be examined through the elastic response spectrum. It is conducted to the elastic and inelastic time history analysis about the long period structure which could reflect the characteristic of Near Fault Ground Motion with the best and it is also examined the aspect of response distribution about the input data. Moreover, the response characteristic of structure is analyzed by investigating the plastic hinge for the purpose of grasp about the inelastic behavior of structure.

• Journal of Ocean Engineering and Technology
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• v.15 no.4
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• pp.115-119
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• 2001

The simulation of motion responses of a dolphin-moored ocean structure in shallow water when it cllides with a ship, has been carried out. The equation of motion in the time domain according to Cummin's theory is employed, and solved by making use of the Newmark-${\beta}$ method. The added mass and damping coefficients involved in the equations are abtained from a three-dimensional panel method in the frequency domain. The impact forces due to ship collision are calculated using both the elastic and non-elastic modelings. The mooring forces for dolphin systems of ocean structure are regarded as linear spring forces.

• International Journal of Precision Engineering and Manufacturing
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• v.3 no.4
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• pp.54-63
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• 2002

In recent years, mechanical systems such as high speed vehicles and railway trains moving on elastic beam structures have become a very important issue to consider. In this paper, a general approach, which can predict the dynamic behavior of a constrained mechanical system moving on a flexible beam structure, is proposed. Various supporting conditions for the foundation support are considered for the elastic beam structure. The elastic structure is assumed to be a non-uniform and linear Bernoulli-Euler beam with a proportional damping effect. Combined differential-algebraic equation of motion is derived using the multi-body dynamics theory and the finite element method. The proposed equations of motion can be solved numerically using the generalized coordinate partitioning method and predictor-corrector algorithm, which is an implicit multi-step integration method.