• Proceedings of the KSR Conference
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• 2008.06a
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• pp.923-931
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• 2008

Coupling rubber pad are important components in railway vehicles. It can be used for reduce shock, vibration and noise. Simple tension, equi-biaxial tension and pure shear test were performed to acquire the coefficient of rubber material which were Mooney-Rivlin and Ogden model. The finite element analysis was executed to evaluate the behavior of deformation and stress distribution by using the commercial finite element analysis code. Useful life evaluation are very important in design procedure to assure the safety and reliability of the rubber components. In this paper, useful life prediction of rubber pad for railway vehicle were experimentally investigated. Accelerated heat-aging test for rubber material were carried. Compression set results changes as the threshold are used for assessment of the useful life and time to threshold value were plotted against reciprocal of absolute temperature to give the Arrhenius plot.

• Clinics in Shoulder and Elbow
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• v.15 no.2
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• pp.99-108
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• 2012

Purpose: To evaluate the clinical results of arthroscopic repair with UU-Tension Band suture for full thickness rotator cuff tear above 4 cm sized. Materials and Methods: From January 2006 to October 2011, in 71 full thickness tears above 4 cm sized which is possible to arthroscopic repair to medial margin of greater tuberosity. The group I is 71 patients which is arthroscopic repair with UU-Tension Band suture, and the group II is 20 cases which is arthroscopic repair with simple suture. Both groups were compared with a VAS score for pain, Activity of Daily Living, UCLA score, KSS score in pre operation, 7 months, 1 year and last follow-up. Statistical analysis was performed by student t test and paired t est. Mean age was 63.2 (52~80) year old, mean follow-up was 38.4 (13~62) months. Results: The VAS scores for pain decreased from 8.1 at preoperative period to 1.6 at postoperative last follow-up period in group I (p<0.05), the score decreased from 7.6 at preoperative period to 1.8 postoperative last follow-up period in group II (p<0.05). The significant difference was not noted between two groups (p<0.05). Mean ADL scores increased from 12.5 at preoperative period to 29.0 post operative last follow-up period in group I (p<0.05), the score increased from 11.3 in pre op to 27.5 post-operative last follow-up in group II (p<0.05). The significant difference was not noted between two groups (p<0.05). The UCLA score increased from 12.9 at preoperative period to 28.7 postoperative last follow-up period in group I (p<0.05), the score increased from 13.8 at preoperative period to 30.1 postoperative last follow-up period in group II (p<0.05). The significant difference was not noted between two groups (p<0.05). In comparing of retear which was checked by MRI and ultrasound evaluated at postoperative period 7 months (mean: 27.5 weeks), the retears were 28% in the group I, and 11 shoulders out of 20 shoulders in the group II. The significant differences were noted between two groups (p<0.05). Conclusion: Arthroscopic repair with UU-Tension Band suture and simple suture for full thickness rotator cuff tear above 4 cm sized were not different clinical result between both groups. However, the significant differences were noted in point of failure rate between both groups.

• Journal of Korean Society of Steel Construction
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• v.23 no.6
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• pp.715-724
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• 2011

A turn buckle inserted between tension members that sustain the structural loads in a suspension structure system is a device that is capable of adjusting the tensile force. The tension member is an important element of a tension structure, but no simple and economical method of measuring a tensile force applied to members has been proposed yet. Thus, a turn buckle for measuring the tensile force in a tension member was developed in this study. The turn buckles of the measurement limit loads of 100kN, 200kN, and 300kN were tested through a theoretical analysis and a finite element analysis. There was no significant difference in the results of the theoretical analysis, FEA, and the test. In addition, the ultimate strength of the turn buckle using FEA showed that a new turn buckle is sufficiently safe to use even when there is a five-times overload in the measurement limit load.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.21 no.2
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• pp.217-222
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• 1997

A simple finite element approach to predicting deformed shape and load-deflection curve of elastomers is presented in this paper. The method is based on several simplifications in deformation pattern and material behavior. The conventional updated Lagrangian approach is employed together with material data obtained by a simple tension test. The presented approach is verified through comparison of predicted results with experimental ones and applied successfully to shape design of various elastomers for shock, vibration and noise control. The advantage of the presented approach lies in easiness, simplicity and accuracy enough for engineering application.

• Magazine of the Korea Concrete Institute
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• v.8 no.3
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• pp.177-185
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• 1996

Four types of experiments were performed to check the similitude of member behavior between prototype and 1 /10 scale models : (1) Test of slender columns with P-$\Delta$ effect, (2) Test of short columns with and without confinement steel, (3) Test of simple beams without stirrups, and (4) 'T-beam test. Based on the results of experiments, the conclusions were made as follows : (1) The P-$\Delta$ effect of slender columns can be almost exactly represented by 1/10 scale model. (2) The effect of confinement on short columns by the hoop steel can be also roughly simulated by 1/10 scale model. (3) The failure modes of simple beams without stirrups are brittle shear failures in prototype whereas those of 1/10 scale models are the ductile yielding of tension steel followed by large diagonal tension cracking and compressive concrete failure. (4) The behaviors of prototype and 1/10 scale model in T-beams appear very similar.

• Clinics in Shoulder and Elbow
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• v.19 no.1
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• pp.48-50
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• 2016

Various tests to help in the clinical diagnosis of distal biceps tendon ruptures have been described. In our experience these tests are painful in the acute setting. We suggest a simple alternative test wherein the biceps muscle belly is held by the examiner and translated medially and laterally. This is done with the forearm flexed to 90 degrees. It is first performed with the biceps relaxed and subsequently performed with the forearm flexed against resistance. In the relaxed forearm the biceps easily translates over 50% of its width. When placed under tension (by flexing against resistance) this translation is significantly reduced. In cases of complete distal biceps tendon rupture, the biceps still translates, even under resisted flexion of the forearm. This simple test is less painful than other described tests, is easy to perform, and aids in clinical diagnosis of distal biceps tendon ruptures.

• Korean Journal of Occupational Health Nursing
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• v.6 no.1
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• pp.53-71
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• 1997

Across sectional study was performed to evaluate the chronic effects on central nerve system(CNS) of cumulative exposure of complex organic solvents, using neurobehavioral test. Subjects were 66 (male) dock yard painters of some large ship industry which is located in Ulsan. The neurobehavioral test battery used in this study was NCTB (Neurabehavioral Core Test Battery recommended by WHO(World Health Organization), which consisted of 7 items-Profile of mood states (POMS), Simple reaction time, Santa Ana dexterity test. Digit span, Digit symbol, Benton visual retention test and Pursuit aiming. The subjects were classified by 3 groups according to duration of employment(group 1 ; less than 9 years, group 2 ; 10-14 years, group 3 ; more than 15 years). The results of performance were analyzed considering of work duration, age, educational level, alcohol drinking, smoking and testing time as confounding factors. Benton visual retention test, pursuit aiming correct dot and sum of dot showed significant differences among the groups, and decreased with increasing work duration. It indicated that the mean scores of performance ability were lowering according to work duration. Besides, the tests that didn't show statistical significances but showed linear trends were depression-dejection, vigor, fatigue of POMS, slowest time of simple reaction time and digit span forward. Most of the neurobehavioral test items were correlated with age and educational level. After controlling of confounding factors-age and educational level, the results followed ; digit span backward was different significantly. Tension-anxiety, depression-dejection, anger-hostility of POMS, SD and slowest time of simple reaction time, Santa Ana dexterity test non-preferred hand, digit span forward, Benton visual retention test and pursuit aiming correct dot decreased with increasing of work duration. The correlation analysis was done in order to find out the relationship between subjective symptom and the scores of neurobehavioral core test battery. According to the results of analysis there were no items that had statistical significant relationship(p<0.05).

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.52 no.4
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• pp.299-307
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• 2016

This study aims to investigate effects of the length of the buoy and sand bag line on the loss of webfoot octopus pot. A numerical modeling and simulation was carried out to analyze the process that the pot gear affected by wave using the mass spring model. Through the simulation, tensions of sand bag line under various condition were investigated by length of buoy and sand bag line. The drag force and coefficient k of an artificial shell used in the webfoot octopus pot was obtained from an experiment in a circular water channel, and the coefficient k was applied to the simulation. To verify the accuracy of the simulation model, a simple test was conducted into measuring a rope tension of a hanging shell under flow. Then, the test result was compared with the simulation. The lengths of the buoy line in the simulation were 1.12, 1.41, 1.80, 2.23, 2.69, and 3.17 times of water depth. The lengths of sand bag line were 10, 20, 30, and 40 meters, and conditions of water depth were 8, 15, 22 meters. 4 meter height and 8 second period of wave were applied to all simulations. As a results, the tension of the sand bag line was decreased as the buoy and sand bag line were increased. The minimum tension of the sand bag line was appeared in conditions that the length of the buoy line is twice of water depth and the sand bag line length is over 40 meters (except in case of depth 8 meters.).

• Computers and Concrete
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• v.1 no.1
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• pp.77-98
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• 2004

This paper presents a numerical model for simulating the nonlinear response of reinforced concrete (RC) shear walls subject to cyclic loadings. The material behavior of cracked concrete is described by an orthotropic constitutive relation with tension-stiffening and compression softening effects defining equivalent uniaxial stress-strain relation in the axes of orthotropy. Especially in making analytical predictions for inelastic behaviors of RC walls under reversed cyclic loading, some influencing factors inducing the material nonlinearities have been considered. A simple hysteretic stress-strain relation of concrete, which crosses the tension-compression region, is defined. Modification of the hysteretic stress-strain relation of steel is also introduced to reflect a pinching effect depending on the shear span ratio and to represent an average stress distribution in a cracked RC element, respectively. To assess the applicability of the constitutive model for RC element, analytical results are compared with idealized shear panel and shear wall test results under monotonic and cyclic shear loadings.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.37 no.10
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• pp.1239-1249
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• 2013

In this study we establish a process to predict hardening behavior considering the Bauschinger effect for zircaloy-4 sheets. When a metal is compressed after tension in forming, the yield strength decreases. For this reason, the Bauschinger effect should be considered in FE simulations of spring-back. We suggested a suitable specimen size and a method for determining the optimum tightening torque for simple shear tests. Shear stress-strain curves are obtained for five materials. We developed a method to convert the shear load-displacement curve to the effective stress-strain curve with FEA. We simulated the simple shear forward/reverse test using the combined isotropic/kinematic hardening model. We also investigated the change of the load-displacement curve by varying the hardening coefficients. We determined the hardening coefficients so that they follow the hardening behavior of zircaloy-4 in experiments.