• Composites Research
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• v.26 no.2
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• pp.135-140
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• 2013

The static test was performed to verify the effect of the joint in the UHPC bridge deck slab and the minimum lap-spliced length was presented. A total of six test members was fabricated to estimate the static behavior of the steam curing UHPC bridge deck slab joint by the four points bending test method. The lap-spliced joint type was expected to be not only simple but also efficient in UHPC structure because of the high bond stress of UHPC. Test results show that the decrease of maximum flexural strength was about 30% and the minimum lap-spliced length which behaved similar to the continued reinforcement in strength and ductility was 150 mm.

• Physical Therapy Rehabilitation Science
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• v.11 no.3
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• pp.370-375
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• 2022

Objective: The purpose of this study was to compare the hip joint muscle strength of patients with chronic back pain with lumbar instability and normal subjects. Design: A case control study. Methods: Five types of lumbar instability test were conducted on forty young women with chronic low back pain for more than six months, and those who had 3 or more positive tests were selected as subjects. To select chronic back pain patients with lumbar instability group, aberrant movement patterns during lumbar flexion test (FMT), prone instability test (PIT), posterior-anterior mobility test (PAT), passive lumbar extension test (PLE), and pressure bio-feedback (PBF) were applied. In addition, a digital muscle strength meter was used to measure the hip flexor, extensor, adductor, and abductor muscles of chronic low back pain patients with lumbar instability group (n=20) and normal subject group (n=20). Results: As a result of comparing the hip joint muscle strength between the chronic back pain patient group with lumbar instability and the normal group, there were significant differences in the hip extensor, abductor, and adductor muscles (p<0.05). Conclusions: Patients of chronic back pain with lumbar instability were found to have weak hip joint muscle strength. Therefore, this study suggest that include hip joint strength exercise for functional recovery of chronic back pain patients.

• Transactions of Materials Processing
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• v.19 no.4
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• pp.217-223
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• 2010

The objective of this study is to propose the FE model for mechanical clinched joint using cohesive zone model to analyze its failure behavior under impact loading. Cohesive zone model (CZM) is two-parameter failure criteria approach, which could describe the failure behavior of joint using critical stress and fracture toughness. In this study, the relationship between failure behavior of mechanical clinched joint and fracture parameters is investigated by FE analysis with CZM. Using this relationship, the critical stress and fracture toughness for tensile and shear mode are determined by H-type tensile test and lap shear test, which were made of 5052 aluminum alloy. The fracture parameters were applied to the tophat impact test to evaluate the crashworthiness. Compared penetration depth and energy absorption at the point where 50% of total displacement in result of FE analysis and experiment test for impact test, those has shown similar crashworthiness.

• Journal of Korean Foot and Ankle Society
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• v.24 no.4
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• pp.165-167
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• 2020

Failure to achieve stable fixation during surgery for a Lisfranc joint injury leads to subtle instability that causes dysfunction and posttraumatic osteoarthritis. Therefore, it is important to check for appropriate fixation during surgery. This paper reports a test that evaluates the joint instability dynamically during the open reduction of the Lisfranc joint and checks the stability after fixation. a Freer elevator was inserted into the interosseous area between the medial cuneiform and second metatarsal base, and a twisting force was applied to evaluate the dynamic instability of the Lisfranc joint. After fixation of the Lisfranc joint, the stability of the fixation could be tested by trying this maneuver with the Freer elevator. Overall, the Freer test can be considered a valuable test in open surgery for a Lisfranc joint injury.

• Journal of Welding and Joining
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• v.33 no.6
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• pp.49-54
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• 2015

Welding process is of importance to assemble products or structures, but also the process is structural weakness due to stress concentration in welding joint. The fatigue design of welded joint requires time & labor consuming fatigue test because the fatigue life is various according to the depth of joint, joint type and load type etc. In fatigue design codes, they guide to classify welding joints with their shape( BS7608, IIW Documents) and provide fatigue assessment information. In terms of numerical method for fatigue analysis, it is also difficult to decide the stress peak in joint because of mesh sensitivity which means that stress value is varies with element type or size on stress concentration zone. Hot-spot method is used generally, but Battelle of United States proposed Master S-N Curve based on structural stresses converted by mechanical equilibrium theory. In this research, we extracted master S-N curve from Battelle's fatigue test DB including test data of various welding joints to apply on Non-Load-Carrying cruciform Joint. Comparing fatigue results between the case of using normal stress and case of structural stress cor the cruciform Joint, The suggested Battelle method showed successive results.

• The Korean Journal of Rehabilitation Nursing
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• v.7 no.2
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• pp.159-168
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• 2004

Purpose: The purpose of this study was to examine effect of Tai-Chi exercise program on joint flexibility for osteoarthritis patients. To evaluate the effects, quasi-experimental study was used for pre and post test with a nonequivalent control group. Method: Fifty-tow subjects participated in the experiment(twenty-seven for experimental group and twenty-five for control group) and they were from two different senior citizen centers in J city. The experiment period was from April 2002 through August 2002. The experiment group took part in Tai-Chi exercise program for eighteen weeks(three times a week for four weeks and five times a week for fourteen week). The exercise was performed for 50 minutes at every time (15 minutes for warm-up, 30 minutes for Tai-Chi exercise, and 5 minutes for ending). In order to pursue study purpose, the SPSS/WIN 8.0 program was chosen for the statistical analysis; ANCOVA was employed in examining test hypothesis; t-test and $x^2$-test were used to examine homogeneity between experimental and control group. Result: The study results were as follows :Score of vertebral joint flexibility increased significantly after of Tai-Chi exercise program. Score of wrist joint extension increased significantly after of Tai-Chi exercise program. Score of wrist joint flexion increased significantly after of Tai-Chi exercise program. Score of elbow joint extension increased significantly after of Tai-Chi exercise program. Score of elbow joint flexion increased significantly after of Tai-Chi exercise program. There was a slight increase of knee joint extension in the Tai-Chi exercise group compared to control group, but without statistical significance. Score of knee joint flexion increased significantly after of Tai-Chi exercise program. Score of ankle plantar flexion increased significantly after of Tai-Chi exercise program. Score of ankle dorsiflexion increased significantly after of Tai-Chi exercise program. Conclusion: As shown in the results, Tai-Chi exercise program can be effective nursing intervention for osteoarthritis patient to improve joint flexibility.

• Transactions of the Korean Society of Mechanical Engineers
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• v.3 no.2
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• pp.43-47
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• 1979

This paper presents the effect of stress relief annealing on mechanical properties in single Vee-groove welding joint. In this experiment, the investigation of annealing effect on mechanical properties of test material carried out by changing the annealing temperature from $600^{\circ}C$ to $900^{\circ}C$ under the given conditions. The results pbtained by this study are as follows: (1) Under the constant welding conditions, the tensile strength of test welded joint decrease in accordance with the increase of annealing temperature. The experimental results show that the reduction rate of tensile strength is about 35.09% of base metal strength. (2) Microhafdness distribution of welded joint bring about the maximum hardness near the bended line of welding joint. (3) Izod impact energy of welded joint in increase in according to the rise of annealing temperature and the peak energy of impact test occurs at $800^{\circ}C$

• The Journal of Korean Physical Therapy
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• v.34 no.4
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• pp.140-148
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• 2022

Purpose: The purpose of this study was to investigate the effects of the scapulothoracic mobilization on subject with lateral epicondylalgia. This was done through lateral slide scapular test, grip strength, visual analogue scale, glenohumeral joint external rotation range of motion. Methods: Before the experiment, Lateral slide scapular test, grip strength, visual analogue scale, glenohumeral joint external rotation range of motion were measured. Scapulothoracic joint mobilization was applied and then measurements were taken again to compared the changes. Results: After applying the scapulothoracic joint mobilization, lateral slide scapular test, grip strength, visual analogue scale, glenohumeral joint external rotation range of motion significantly improved. Conclusion: This study found that the scapulothoracic mobilization was effective in improving functional aspects and pain on subject with lateral epicondylalgia. The results suggest that the scapulothoracic joint mobilization is a significant considered intervention method that could be used for subject with lateral epicondylalgia.

• Journal of the Korean Society for Precision Engineering
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• v.22 no.4
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• pp.188-193
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• 2005

The purpose of this paper is to develop a more precise damper model of the joint for the quantification of the joint mechanical properties. We modified the linear damper model of a knee joint model to nonlinear one. The normalized RMS errors between the simulated and measured joint angle trajectories during passive pendulum test became smaller with the nonlinear damper model than those of the linear one which indicates the nonlinear damper model is better in precision and accuracy. The error between the experimental and simulated knee joint moment also reduced with the nonlinear damper model. The reduction in both the trajectory error and the moment error was significant at the latter part of the pendulum test where the joint angular velocity was small. The nonlinearity of the damper was significantly greater at thin subject group and this indicates the nonlinearity is a useful index of joint mechanical properties.

• Journal of Welding and Joining
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• v.33 no.3
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• pp.25-31
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• 2015

Due to environmental regulations (RoHS, WEEE and ELV) of the European Union, electronics and automotive electronics have to eliminate toxic substance from electronic devices and system. Specifically, reliability issue of lead-free solder joint have an increasing demand for the car electronics caused by ELV banning. The authors prepared engine control unit and cabin electronics soldered with Sn-3.0Ag-0.5Cu (SAC305). To compare with the degradation characteristics of solder joint strength, thermal cycling test (TC), power-thermal cycling test (PTC) and series tests were conducted. Series tests were conducted for TC and PTC combined stress test using the same sample in sequence and continuously. TC test was performed at $-40{\sim}125^{\circ}C$ and soak time 10 min for 1000 cycles. PTC test was applied by pulse power and full function conditions during 100 cycles. Combined stress test was tested in accordance with automotive company standard. Solder joint degradation was observed by optical microscopy and environment scanning electron microscopy (ESEM). In addition, to compare with deterioration of bond strength of quad flat package (QFP) and chip components, we have measured lead pull and shear strength. Based on the series test results, consequently, we have validated of series test method for lifetime and reliability of Pb-free solder joint in automotive electronics.