• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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• 2003.05a
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• pp.269-273
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• 2003

During the laser welding, weldments are suddenly heated by laser beam and cooled. This phenomenon gives occasion to complex welding residual stresses, which have a great influence on structural instability strength, in laser welds. However, a relevant research on this field is not sufficient until present and residual stress measurements have experimental and practical limitations. For these reasons a numerical simulation may be attractive in order to solve the residual stress problem. In order to determine the distribution of heat and welding residual stresses in laser welds with the nail-head shape, authors conduct the finite element analysis (two-dimensional unstationary heat conduction & thermal elasto-plastic analysis). From the result of this study, we can confirm the stress concentration is occurred at the place of melting line shape changed in laser welds with the nail-head shape.

• Journal of Physiology & Pathology in Korean Medicine
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• v.18 no.3
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• pp.789-791
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• 2004

We study on the video-capillaroscopy system for look a.t the nail fold capillary by the computer. This system is composed of the luminous source-producer, image-input, phase microscope. The method and contents of observation on this system are seperated from the image-analysis of nail fold capillary form-patterns and the currents of hematocytes. Therefore we think this system is possible to the practical clinic use for the basic model on the cardiac failure and the deficiency(血虛), stagnant(血瘀) of blood in human.

• Journal of Nutrition and Health
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• v.12 no.4
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• pp.25-27
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• 1979

The analysis of nail nitrogen content reflected recent nutritional status. Therefore, estimation of nail nitrogen content has been previously reported in a small group of neonates ana school children. Nail samples were obtained from 52 economically middle and 21 low classes. The contents of nitrogen in their fingernails were determinded by micro-Kjeldahl method. Mean nail nitrogen content was $133.1{\pm}8mg/g$ in the middle class which is significantly higher than that of the low class $122.1{\pm}8mg/g$. The nitrogen contents of nails obtained in summer were found by analysis of variance and student's t-test to he lower than those obtained in winter.

• Journal of Korean Neurosurgical Society
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• v.55 no.5
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• pp.293-295
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• 2014

Post-traumatic cerebral infarction (PTCI) is a secondary insult which causes global cerebral hypoxia or hypoperfusion after traumatic brain injury, and carries a remarkable high mortality rate. PTCI is usually caused by blunt brain injury with gross hematoma and/or brain herniation. Herein, we present the case of a 91-year-old male who had sustained PTCI following a low-energy penetrating craniocerebral injury due to a nail without evidence of hematoma. The patient survived after a decompressive craniectomy, but permanent neurological damage occurred. This is the first case of profound PTCI following a low-energy penetrating craniocerebral nail injury and reminds clinicians of possibility this rare dreadful complication for care of head-injured patients.

• Journal of the Korean Wood Science and Technology
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• v.24 no.3
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• pp.65-71
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• 1996

In the design of wood structures, the consideration of the dynamic load effect has been increased. Generally, damping ratio is presented as the method of considering dynamic load effect. So, the relationship between joint type and damping ratio was investigated. It has been known that the joint extremely damp the dynamic load in wood structures. Static test was performed to determine the effects of nail size and friction area on joint strength and stiffness. Joint strength and stiffness were increased with nail size. However, the static properties of joint was not affected by friction area. Cyclic test was performed to determine the effects of nail size, friction area and load magnitude on damping ratio, Damping ratio was affected by all factors. Increasing the width of the bottom plate was suggested as the most adequate method to increase the damping ratio without the reduction of the static properties of the structures.

• Structural Engineering and Mechanics
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• v.42 no.3
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• pp.383-407
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• 2012

A numerical approach to simulate the behaviour of timber shear walls under both static and dynamic loading is proposed. Because the behaviour of timber shear walls hinges on the behaviour of the nail connections, the force-displacement behaviour of sheathing-to-framing nail connections are first determined and then used to define the hysteretic properties of finite elements representing these connections. The model nails are subsequently implemented into model walls. The model walls are verified using experimental results for both monotonic and cyclic loading. It is demonstrated that the complex hysteretic behaviour of timber shear walls can be reasonably represented using model shear walls in which nonlinear material failure is concentrated only at the sheathing-to-framing nail connections.

• International Journal of Korean Welding Society
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• v.3 no.1
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• pp.17-22
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• 2003

During the laser welding, weldments are suddenly heated and cooled by laser beam of high density energy. This phenomenon gives an occasion to complex welding residual stresses, which have a great influence on structural instability, in laser welds. However, relevant researches on this field are not sufficient until now and residual stress measurements have experimental and practical limitations. From these reasons, a numerical simulation may be attractive in order to solve the residual stress problem. For clarifying the distribution of heat and welding residual stresses in laser welds with the nail-head shape, authors conduct the finite element analysis (two-dimensional unstationary heat conduction & thermal elastic and plastic analysis). From the results, we can confirm the stress concentration occurs at the place of melting line shape changed in laser welds with the nail-head shape.

• Geomechanics and Engineering
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• v.38 no.4
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• pp.421-437
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• 2024

The soil nailing method entails the utilisation of nails to reinforce and stabilise a zone of soil mass. This is widely used for various applications due to its effective performance under various loading conditions. The seismic response of 6m high vertical soil-nailed cut in various site classes under dynamic excitations has been investigated in this study considering various lengths and inclinations of nails. The influence of frequency content of dynamic excitation on the response of structure has been assessed through finite element analysis using time history data of three different earthquakes. The seismic stability of the nailed cut in retaining soil in various sites under El Centro, Kobe and Trinidad earthquake ground motion is evaluated based on maximum acceleration response, maximum horizontal deformation, earth pressure distribution on the wall and maximum axial force mobilised in nails. The optimum nail inclination is identified as 15° and a minimum nail length ratio of 0.7 is essential for a stable vertical cut under dynamic excitations.

• Proceedings of the Korean Geotechical Society Conference
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• 1998.10a
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• pp.217-224
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• 1998

• Journal of Korean Foot and Ankle Society
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• v.19 no.4
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• pp.171-175
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• 2015

Purpose: Tibiotalocalcaneal arthrodesis has been used as a treatment option for severe deformity including Charcot arthropathy, avascular necrosis of the talus, and severe osteoarthritis of the ankle and subtalar joint. The purpose of this study was to evaluate the result of the surgical outcome of tibiotalocalcaneal arthrodesis using a retrograde intramedullary nail. Materials and Methods: Tibiotalocalcaneal arthrodesis using a retrograde intramedullary nail was performed by one surgeon in 36 cases. Clinical and radiological finding was evaluated using assessment of fusion time, 5th metatarsal-tibial angle, possibility of postoperative complication, visual analogue scale for pain and American Orthopaedic Foot and Ankle Society (AOFAS) score. Results: Union was achieved in 33 cases at an average of 23 weeks (11~29 weeks). There were 3 cases of nonunion and 1 case of reoperation. Nail-tibial angle tended to be larger in nonunion cases. AOFAS score showed significantly poor outcome at malalignment (${\geq}5^{\circ}$), negative value of 5th metatarsal-tibial angle. Conclusion: Tibiotalocalcaneal arthrodesis using a retrograde intramedullary nail is considered a useful treatment option for severe destruction and deformity involving ankle and subtalar joint.