• Transactions of the Korean Society of Mechanical Engineers A
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• v.20 no.6
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• pp.1862-1871
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• 1996

The puopose of this paper is sto modify the current LBB criteria. The validity of current LBB criteria and current standard LBB analysis mehtod are evaluated using linear elastic fracture mechanics and elastic-plastic fracture mechanics. The results of evaluation demonstrate that the current LBB driteria are very conservative and some level of margins already exist in the standard LBB analysis method. Thus, the margin on load .root. and margin on crack size 2 can be eliminated to extend LBB application for the samller diameter pipe.

• Proceedings of the KWS Conference
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• 2001.05a
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• pp.189-191
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• 2001

This study introduces the new way for the evaluation criteria of the Mash-Seam Tailored Blank weldability, The materials used are low carbon automotive galvanized and high strength steels and the evaluation of weldability are examined with various thickness. Welding tests were conducted for both similar thickness and dissimilar thickness cases. The criteria developed for optimum welding conditions were based on the relationship among results of die press forming test, weld transverse tensile test, Erichsen test and microhardness measurements. The application of the developed criteria(fracture ratio, strength ratio, etc) in obtaining optimum welding condition revealed that a weld which satisfied ant of the criteria did not fracture during actual die press test.

• Proceedings of the KWS Conference
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• 2001.10a
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• pp.81-84
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• 2001

This study introduces the new way for the evaluation criteria of the Mash-Seam Tailored Blank weldability, The materials used are low carbon automotive galvanized and high strength steels and the evaluation of weldability are examined with various thickness. Welding tests were conducted for both similar thickness and dissimilar thickness cases. The criteria developed for optimum welding conditions were based on the relationship among results of die press forming test, forming limit diagram, Erichsen test and microhardness measurements. The application of the developed criteria(fracture ratio, strength ratio, etc) in obtaining optimum welding condition revealed that a weld which satisfied ant of the criteria did not fracture during actual die press test and FLD dome test.

• Journal of Korean Foot and Ankle Society
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• v.10 no.2
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• pp.190-195
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• 2006

Purpose: To evaluate the results of open reduction and internal fixation for displaced talar neck fracture. Materials and Methods: Fourteen patients were followed for more than 1 year after open reduction and internal fixation of displaced talar neck fracture. The mean age was 41.5 years, and the mean follow-up period was 3.8 years. There were 10 type II, 3 type III and 1 type IV fractures per Hawkins. There were 3 open fractures. Clinically AOFAS ankle-hindfoot scale and Hawkins criteria were utilized. Radiologically quality of reduction, duration of bony union, avascular necrosis and posttraumatic arthritis were evaluated. Results: At last follow-up, AOFAS scale was mean 89.1 points. There were 8 excellent, 4 good, and 2 fair results according to Hawkins criteria. Radiologically anatomical reduction was obtained in 13 cases. Mean duration of bony union was 11.8 weeks. There were 3 avascular necrosis and 2 post-traumatic arthritis. There was no significant difference in the incidence of avascular necrosis between early operation group and surgically delayed group. Conclusion: Accurate open reduction and rigid internal fixation seem to be prerequisites for satisfactory treatment of a displaced talar neck fracture.

• Journal of Korean Neurosurgical Society
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• v.65 no.2
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• pp.173-179
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• 2022

Disabilities can emerge due to traumatic spinal fractures. In terms of sacrococcygeal spine, because of its unique anatomic structure with minimal movement, the possibility for it to have a disability is relatively low. In Korea, unlike most disability criteria, private insurance companies acknowledge angular deformities caused by vertebral fractures as disabilities according to their degree, so there were several cases where patients required compensation, arguing angular deformity caused by sacrococcygeal fracture, which in some cases led to legal conflicts. Except the Act Welfare of Persons with Disabilities which recognizes only severe angular deformity affecting internal organs as disability and the industrial accident disability evaluation which does not recognize coccygeal fracture as disability but rarely recognizes sacral vertebra deformity equivalent to compressive deformation, there is little or no case where angular deformity is recognized as disability. Given the impairment evaluation standards in social insurance, McBride system, American Medical Association (AMA) guides, and newly proposed standards by the Korean Academy of Medical Sciences (KAMS), the most contentious point in the general terms and conditions of private insurance is spinal deformity. To overcome controversy over disability evaluation, the private insurance sector is now applying criteria for axial skeleton to sacrococcygeal vertebrae through revision of standards. Under these circumstances, it is fair to recognize sacrococcygeal fracture as impairment in terms of the pelvis only when the fracture leaves serious deformity and neurological symptoms with clear relevancy. Though it may not be easy to develop accurate disability evaluation standards, improvement is necessary to remove any irrationalities and make the standards as objective as possible.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2008.10a
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• pp.249-252
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• 2008

Micro V-notching process has been used to manufacturing the safety component in Li-Ion battery. These kinds of safety component in Li-Ion battery plays an important role in the explosion from excessive overheating. Therefore, it is very crucial to estimate accurately the working pressure range of the safety component with micro V-notch. In this study, the relationship with the working internal pressure in Li-Ion battery and fracture phenomenon in micro V-notch was investigated through the numerical analysis. The numerical analysis is especially adopted the finite element method with ductile fracture criteria.

• Geomechanics and Engineering
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• v.11 no.2
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• pp.253-267
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• 2016

The stability of surrounding rock will be poor when the tunnel is excavated through nearly horizontal stratum. In this paper, the instability mechanism of local nearly horizontal stratum in super-large section and deep buried tunnel is revealed by the analysis of the macro failure and micro fracture. A structural model is proposed to explain the mechanics of surrounding rock collapse under the action of stress redistribution and shed light on the macroscopic analytical approach of the stability of surrounding rock. Then, some highly effective formulas applied in the tunnel engineering are developed according to the theory of mixed-mode micro fracture. And well-documented field case is made to demonstrate the effectiveness and accuracy of the proposed analytical methods of mixed-mode fracture. Meanwhile, in order to make the more accurate judgment about yield failure of rock mass, a series of comprehensive failure criteria are formed. In addition, the relationship between the nonlinear failure criterion and $K_I$ and $K_{II}$ of micro fracture is established to make the surrounding rock failure criterion more comprehensive and accurate. Further, the influence of the parameters related to the tension-shear mixed-mode fracture and compression-shear mixed-mode fracture on the propagation of rock crack is analyzed. Results show that ${\sigma}_3$ changes linearly with the change of ${\sigma}_1$. And the change rate is related to ${\beta}$, angle between the cracks and ${\sigma}_1$. The proposed simple analytical approach is economical and efficient, and suitable for the analysis of local nearly horizontal stratum in super-large section and deep buried tunnel.

• Journal of Veterinary Clinics
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• v.15 no.1
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• pp.222-227
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• 1998

This survey was based on the data of one hundred four dogs with 108 case,T of fracture admitted to the veterinary teaching hospital, College of Veterinary Medicine, Kyungpook National University and 24 private small animal hospitals from January, 1995 to Decemberi 1996. The results were analyzed as following criteria; the distribution of fractures causes of fractured age and sexual distributions month of the most frequencel total body weights presence of communicating external wound, extent of damaged direction of fracture line, location of fracture liner fracture managements fixations methods, fixations methods according to location of fracture. The results of survey were as follow: 1. Main distribution of fracture; radius . ulna (23.1%).2. Causes of fracture; road toraffic accident (39.4 T,). 3. Age; over 24 months (27.9%). 4. Sex; male (53.89)), female (46.2%). 5. Month of the most frequence; July (14.4%) 6. Total body weight: 2-5 kg (45.27)). 7. Presence of communicating external wound; closed fracture (94.2%). 8. Extent of damage; complete fracture (92.6%). 9. Direction of fracture line: comminuted fracture (27.8 To). 10. Location of fracture line; diaphysis (62.0%). 11. Fracture management; open reduction (58.3% ). 12. Fixation methods; not treat (22.2%). 13. Fixation methods according to location of fracture; radius ulna-Kirschner wire fixation (45.5%), femur. shaft-intramedullary pinning (71.4%), pelvis-bone plate (53.3%), metacarpus-not treat, Kirschner wire fixation (each 30.8%).

• Journal of the Korean Society for Nondestructive Testing
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• v.32 no.2
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• pp.131-141
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• 2012

A field theoretical approach to deformation and fracture of solid-state material is outlined, and its application to diagnosis of deformational status of metal specimens is discussed. Being based on a fundamental physical principle known as local symmetry, this approach is intrinsically scale independent, and capable of describing all stages of deformation on the same theoretical foundation. This capability enables us to derive criteria that can be used to diagnose transitions from the elastic to plastic regime, and the plastic to fracturing regime. For practical applications of these criteria, an optical interferometric technique known as electronic speckle-pattern interferometry is proved to be quite powerful; it is able to visualize the criteria as a whole image of the object on a real-time basis without numerical processing. It is demonstrated that this method is able to reveal loading hysteresis as well.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.19 no.2
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• pp.191-199
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• 1997

Mandibular trauma is developed due to traffic accident, fall down, industrial injury, and others. TMJ disorder is usually also developed after facial traumatic injury. Many authors suggested that disc displacement or tearing, acute synovitis, TMJ ankylosis, traumatic arthritis, or effusion are developed after facial trauma. It is still very controversible what is the best treatment of TMJ injury such as condylar fracture and meniscal injury. In TMJ injury, synovial inflammation is developed and pain mediators such as prostaglandin E2 or leukotriene B4 are released from the synovial membrane. This can be a cause of TMJ disorder. I present a variety of experimental study about the condylar fracture and meniscal injury and enzyme-immunoassay of synovial fluid after mandibular trauma that have been studied since 1992 and establish the treatment criteria of traumatic TMJ injury. I think that the treatment option of condylar fracture depends upon the surgeon's criteria exclusively. There are no significant differences between conservative and surgical treatment. If the aggressive functional physical therapy and long-term followup be performed, the favorable functional recovery of TMJ can be obtained. And I think that the initial surgical management of meniscus of TMJ is unnecessary in condylar fracture. And also arthrocentesis can be available to release the patient's subjective symptoms and improve the healing of injured TMJ.