• Transactions of the Korean Society of Automotive Engineers
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• v.21 no.6
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• pp.201-208
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• 2013

Recently, there has been an active study about weight reduction for automotive. This study is prediction and evaluation of one pice type steering component, which is universial joint. Steering system is a core of major safe device in vehicle. Universial shaft adopted in steering system transmit steering torque between olumn and steering gear. Conventional universial shaft is produced by welding process because of geometric complexity. But welding process has some weakness such as deflection on surface, residual stress, and deteronration of material properties so it can deteriorate durability of vehicle.

• Journal of Applied Reliability
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• v.16 no.2
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• pp.125-133
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• 2016

Purpose: The purpose of this study is to evaluate durability of platform safety step system in railway. Method: We performed finite element analysis & durability analysis of platform safety step system with VPD (Virtual Product Development) techniques and examined the durability standard & qualification life through the rig test during no failure test time in reliability qualification test. We continued to test 1 million cycles in KRS (Korea Railway Standard) for system's robust design performance. Result: FEM analysis results are 14.9MPa & 14.7MPa of pin-joint, pivot and durability analysis result is above 1 million cycles. we calculated theoretically no failure test time 855,000 cycles and through the 1 million cycles durability rig test in KRS standard we confirmed product quality. Conclusion: This platform safety step system was designed very safe in terms of a mechanical strength & durability.

• Proceedings of the Korean Geotechical Society Conference
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• 1993.03a
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• pp.41-48
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• 1993

The 2nd phase of Seoul Subway, Lines 5,6,7 and 8, is in progress. To reduce the surface traffic congestion during construction the greater part of the system has been engineered by bored tunnelling. The current tunnelling methodology is based on the New Austrian Tunnelling Method. Serveral collapses have been reported to date. Most of the collapses took place in the area forwed with soft ground. The modes and causes of the collapses were progressive failures in the unsupported surface and sliding failures due to the unfavourable joint direction. The major causes turned out to be the weakness of ground and the sudden influx of ground water from the surface. Some measures to prevent the failures are also presented. To ensure the safe tunnelling ghrough the soft ground the unsupported excavation area has to be minimized and closed as early as possible. Additional support measures such as supporting core, sealing shotcrete, forepoling, spread footing, face rock bolting and grouting should be employed as well depend on ground conditions.

• Proceedings of the KSME Conference
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• 2003.11a
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• pp.1566-1571
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• 2003

PGO(Powered Gait Orthosis) mounted with pneumatic muscle as an actuator is upgraded model from RGO(Replicate Gait Orthosis) for paraplegia patients to walk easy and safe. Pneumatic muscles supply powers to both hip joint during PGO gait. The objective of this research is to develop the PGO gait simulation model. Dynamic model of PGO linkage system is processed. Mathematical model of pneumatic muscle was developed and combined it with PGO linkage system. Developed simulation model will be used as a tool for evaluation of the efficiency of pneumatic muscle and for analysis the PGO system.

• The Journal of Korean Orthopaedic Ultrasound Society
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• v.4 no.1
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• pp.50-58
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• 2011

Ultrasound-guided intervention is very safe and useful for the treatment of shoulder pain. Injection techniques vary according to the diseases causing shoulder pains. This review tried to describe various methods of the ultrasoundguided intervention around the shoulder joint.

• Toxicological Research
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• v.32 no.1
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• pp.65-72
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• 2016

Man-made cadmium (Cd) emissions can be transported between environmental matrices and the food chain. Food is the primary source of Cd exposure among general population as a consequence of the bioconcentration of Cd from soil. Chronic Cd exposure has been reported to be associated with chronic kidney disease, osteoporosis, diabetes, cardiovascular disease and cancer. The Joint FAO/WHO Expert Committee on Food Additives (JECFA) established the safe level of Cd intake as provisional tolerable monthly intake (PTMI) of $25{\mu}g/kg\;bw$ in 2010. The major food groups that contribute to the most Cd exposure are rice and grains, shellfish and sea food, meat including edible offal, and vegetables. A number of studies reported the high Cd contaminated levels in foods from polluted areas in Thailand. The results are of high concern since the contaminations occur in foods that are major Cd contributors. Thus, in this review, the current situations of Cd contaminated foods in polluted areas of Thailand are summarized. In addition, the Cd intakes from selected scenarios are estimated to assess the potential health risk to consumers and the suggestions are also included.

• Proceedings of the KWS Conference
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• 2005.11a
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• pp.38-40
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• 2005

Fracture mechanics evaluation of stress corrosion cracking (SCC) in the dissimilar metal weld (DMW) for the nuclear piping system is performed; simulating the transition joint of the ferritic nozzle to austenitic safe-end fabricated with the Inconel Alloy A82/182 buttering and welds. Residual stresses in the DMW are computed by the finite element (FE) analyses Then, to investigate the SCC in the weld root under the combined residual and system operation stresses, the fracture mechanics parameters for a semi-elliptical surface crack are evaluated using the finite element alternating method (FEAM). As a result, it is found that the effect of weld residual stresses on the crack-driving forces is dominant, as high as three times or more than the operation stresses.

• Journal of Korean Foot and Ankle Society
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• v.16 no.1
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• pp.1-8
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• 2012

Major technologic advances in fiberoptic light transmission, video cameras, and instrumentation have allowed great advances in small-joint arthroscopy. Arthroscopy in particular is now well established procedure for accurate diagnosis and operative management of certain ankle disorders. The small size of the ankle and significant periarticular soft tissue structures make placement and advancement of the arthroscope and instrumentation more difficult than in larger joints. Successful arthroscopy of the ankle requires knowledge of the regional anatomy and a familiarity with the available arthroscopic portals. This review article is going to describe the gross and arthroscopic anatomy of the ankle as it relates to current arthroscopic techniques. Particular emphasis is placed on the anatomic relations of the important osseous and soft tissue structures for a safe, reproducible approach to arthroscopic treatment of ankle pathology. Also, current arthroscopic equipment and instruments are included.

• Tunnel and Underground Space
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• v.4 no.2
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• pp.119-131
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• 1994

This is a Double-Track Railway tunnel in typical Tae-Gu black and gray shale forming part of the No.1 Line of the Tae-Gu Subway. The main fault zone at tunnel is a moderately to highly weathered and closely jointed zone, 0.5 m wide with associated paralled jointing which is slickensided and fractured. After excavation by blasting, the soft rocks should need to be reinforced with optimal supporting pattern which might be better redesigned through the consideration of the results of in-situ rock measurements at the field. Performances fo the field tests included Point Load Test, Schmidt Hammer Test, and field joint measurement gave the detail data for the optimum support design and safe excavation of the No.1 Line of Tae-Gu Subway at the No.1-7 consturction site adn the safety of this redesigned supports system was analysed by the FDM program FLAC.

• PNF and Movement
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• v.11 no.1
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• pp.63-68
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• 2013

Purpose : The purpose of this study was to examine changes in spatiotemporal gait parameters(STGPs) in healthy adults before and after a immediate intervention of a Mulligan taping program(MTP). Methods : A total of 12 healthy adults(mean age, 20.82 years; age range, 19-24 years) participated in the study. performance was assessed by recording changes in the STGPs using GaitRite. comparisons of changes in the STGPs at pre-intervention and at dischange were analyzed using the Wilcox signed rank test and Mann-Whithney U test. Results : There was a significant improvement in the outcome measures of STGPs(stride length, velocity) after immediate of MTP(p<0.05). However, no significant different pre-test and post-test step width, toe angle(p>0.05). Conclusion : Participants in a MTP improves STGPs, thereby increasing the ability of healthy adults to maintain gait. MTP appears to be a safe and efficacious, noninvasive treatment modality for patients with knee joint disease.