• The tire
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• s.75
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• pp.15-23
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• 1978

금속염을 첨가한 고무를 아연판과 접착가황하여 아연면의 첨가금속과 유황의 분포를 XMA에 의해 구했다. 가황중에 아연면으로 이행하는 것은 Co, Cu, Pb를 포함한 유기금속염뿐이였다. 고무 속의 유리유황도 이들 금속염과 함께 아연판으로 이행되어 왔다. 나프텐산코발트 중의 Co는 아연층내에 확산되어 분포된 데 반하여, S는 아연판표면에만 분포되어 있다. 양자가 아연판으로 이행되는 양은 첨가량에 비례해서 증가하였다. 고무와 아연판의 접착력은 Co량 0.6%까지는 증가하고, 그 이상의 첨가에서는 현저하게 저하되었다. 나프텐산코발트의 첨가량을 증가시키면 가황고무 중의 망목쇄농도는 변하지 않으나 유리유황은 감소하였다. 가황고무 중의 잔류나프텐산코발트는 60℃이상의 열처리온도에서 산화를 촉진하고 접착력도 저하시킨다. 카아본블랙을 배합하지 않은 NR의 유전거동보다 첨가한 나프텐산코발트는 가황온도에서 고무 분자의 주쇄 Segment의 완화 mode에 영향을 준다는 것을 알았다.

• Clinics in Shoulder and Elbow
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• v.16 no.1
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• pp.27-32
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• 2013

Purpose: The purpose of this study is to evaluate the clinical and radiological outcomes of treatment of humerus shaft simple fracture by minimally invasive percutaneous osteosynthesis (MIPO) technique using locking compression plate (LCP). Materials and Methods: Six patients who were operated for humerus shaft simple fracture from August 2010 to May 2011 were enrolled for this study. We checked the cause of injury and the accompanying injuries and evaluated the operation time, the clinical and radiological period of union, postoperative range of motion of the shoulder and elbow joint, pain, activities in daily living, radiologic alignment, and other complications. Results: The clinical period of bone union was 7.2 weeks on average, and the radiologic period of bone union was 8 weeks on average. Follow-up period was more than 12 months in all cases. The angulation through postoperative alignment was 2.8 degrees in AP view and 2 degrees in lateral view. The postoperative range of motion was 167 degrees in forward flexion, 50 degrees in external rotation, and thoracic vertebra 12 level in internal rotation. The average value of visual analogue scale (VAS) was 1.2 and that of KSS was 91.3. The American Shoulder and Elbow Surgeons' score (ASES) was 26.5 and the UCLA score was 31.5. Conclusion: MIPO technique for the humerus shaft simple fracture showed good functional and radiological outcomes and may be considered as one of the treatment options for humerus shaft simple fracture.

• Clinics in Shoulder and Elbow
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• v.14 no.1
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• pp.27-34
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• 2011

Purpose: We examined the clinical and radiological outcomes for displaced proximal humerus fractures that were treated with a PHILOS angular stable plate. Materials and Method: Forty four patients who underwent surgery between March 2007 and February 2010 were included in this study. All the cases were followed up for an average of 12 months. All the patients were examined and interviewed using the Visual Analog Scale (VAS) score, the Constant score and standardized X-rays to check the neck-shaft angle (NSA) and the presence of medial support. Results: The average Visual Analog Scale score was 2.8 points and the average Constant score was 70.5 points. The average neck shaft angle was $122.5^{\circ}$ and this was statistically significant between the good result group and the poor result group. There were 36 cases of the presence of medial support and 8 cases of the absence of medial support and the difference was statistically significant. Complications such as fixation failure happened in 12 cases. Conclusion: PHILOS angular stable plate fixation as an operative treatment for displaced proximal humerus fractures is a good and reliable treatment option.

• Clinics in Shoulder and Elbow
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• v.13 no.2
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• pp.194-201
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• 2010

Purpose: We evaluated clinical and radiological results for open reduction and internal fixation of acromioclavicular dislocation without coracoclavicular ligament repair after removal of implants. Materials and methods: Clinical and radiological results were obtained for 53 patients who underwent open reduction and internal fixation of an acromioclavicular joint dislocation between 1998 and 2007. A total of 21 patients were treated with a modified-Phemister method and 32 patients were treated with a Hook plate method. All subjects were surveyed after removal of their implants. The Constant scoring system was administered postoperatively to evaluate clinical results. Radiologic outcomes were evaluated by both coracoclavicular intervals on plain films. Results: Constant scores were $87.59{\pm}7.8$ in the Phemister group and $89.35{\pm}5.3$ in the Hook plate group. For both groups, the mean coracoclavicular interval at preoperative radiography was 15.9 mm at the injured site and 8.0 mm at the opposite site. After metal removal, the mean difference between coracoclavicular distances between normal and injured sites were 1.0 mm for the Hook plate group and 1.2 mm for the modified Phemister method group (p>0.05). Conclusion: Open reduction and internal fixation of an acromioclavicular joint without coracoclavicular ligament repair shows good long-term clinical and radiological results.

• Clinics in Shoulder and Elbow
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• v.13 no.2
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• pp.260-265
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• 2010

Purpose: To report the clinical results of two cases of coronoid process fractures that were treated with volar plating through a medial approach. Materials and Methods: Two fractures of the coronoid process that needed to be fixed were managed with open reduction and internal fixation through a medial approach using 2.4 mm locking compression plates (Compact Hand set$^{(R)}$, Synthes, Switzerland). The patients were followed up for 14 months and 17 months and were evaluated using the Mayo Elbow Performance Score (MEPS). Results: The MEPS was 95 for Case 1 and 100 for Case 2. Active elbow joint motions were $5^{\circ}-120^{\circ}$ (Case 1) and $0^{\circ}-130^{\circ}$ (Case 2). Supination and pronation fully recovered. Conclusion: Satisfactory results can be obtained in cases of coronoid process fractures because volar plating through a medial approach allows sound fixation and early mobilization of the elbow joint.

• Journal of Korean Orthopaedic Sports Medicine
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• v.5 no.1
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• pp.58-62
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• 2006

Purpose: To evaluate the result of operative treatment with plate and wire fixation for fractures of the distal clavicle. Materials and Methods: We assessed 9 cases of fractures of the distal clavicle that were treated by plate and wire fixation from March 2001 to July 2003 and followed up over 1year. We used the reconstruction plate as a buttress and performed cerclage wiring to fix comminuted fracture site. The functional result of shoulder was evaluated by the scoring system of Rowe. Results: The average periods of bony union was 9 weeks in all cases. According to Rowe scoring system, the functional result was exellent in 7 cases and good in 2 cases. There was no LOM of shoulder and traumatic arthritis in AC joint. But there was skin irritation in 1 case. Conclusion : The operative method by reconstruction plate and wire fixation for distal clavicular fracture was useful when there were comminuted fracture. This method seems to be simple and satisfactory in terms of improvement of range of motion of shoulder, restoration of function and rare complication.

• Journal of Yeungnam Medical Science
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• v.14 no.1
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• pp.209-219
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• 1997

Objectives: Anterior approach to achieve arthrodesis of the cervical spine has become a widely accepted and often-used approach since its earliest reports by Bailey and Badgley, Smith and Robinson and Cloward. However, anterior interbody fusion in the presence of the posterior instability may be complicated by the bone graft dislodgement, kyphotic defomity or nonunion. As an attemp to prevent this undesirable complication, additional methods such as skeletal traction, halo appratus or even posterior fusion has been utilized. Therefore, The cervical spine locking plate(CSLP) with the anterior intervertebral body bone grafting provide immediate cervical stabilization and widely successful in achieving fusion. Material and methods: This study analysed 14 patients who underwent a single anterior procedure and application of CSLP for the treatment of the cervical spinal disorder. Eleven patients were disc herniations and three patients were traumatic lesion. The average age of the patient was 47 years and the mean follow up periods was 20 months ranging from 13 to 27 months. Results: Ambulation was started 2nd day after the operation with the aid of the Philadelpia orthoses. Bone union was observed 13 cases on average 12 weeks after operation. The one case was nonunion with plate breakage without clinical symptom. Conclusion: Anterior fusion with CSLP are thought to be a safe and valuable method for treating cervical spine disorder.

• Journal of Aerospace System Engineering
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• v.13 no.2
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• pp.66-72
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• 2019

The observation satellites which uses high heat-dissipating equipment such as synthetic aperture radar (SAR) satellites require a radiator to transmit heat from the equipment into outer space. However, during cold conditions it requires a heater to maintain the temperature of equipment within the allowable minimum limit when it is not in operation. In this study, we proposed a variable conductivity radiator that changes its thermal conductivity value through movement of the liquid metal between two reservoirs based on the temperature condition. This reduces the power consumption of the heater by limiting heat transfer path to the radiator in cold condition, while effectively transferring heat to the radiator during hot condition. The feasibility of the proposed radiator was validated through comparison of the thermal control performance with the conventional fixed conductivity radiator via a thermal analysis.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.27 no.3
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• pp.372-380
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• 2003

Impact tests were conducted to study the effect of angle ply and metal laminate on impact damage characteristics of Fiber Metal laminates (FML). Impact tests were conducted using drop weight impact machine and damage behavior were analyzed by comparing with load-displacement curve and surface observation and microscopic observation of cross sections. The effect of angle ply on impact characteristics of FML are influenced by property of metal laminate. i.e., when the metal laminate is not enough to strong to prevent fiber debonding, Angle ply FML is superior to singly oriented ply (SOP) FML because angle ply enhance the stiffness by fiber supports and prevent (rack propagation. However, when the metal laminate is enough to strong to prevent fiber debonding, SOP FML is superior to Angle ply FML because the fiber of lower ply in Angle ply FML are more stressed than that of SOP FML.

• Clinics in Shoulder and Elbow
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• v.11 no.2
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• pp.177-184
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• 2008

Purpose: The purpose of this study was to evaluate the results of eight cases of coronoid process fractures that were fixed with a plate. Materials and Methods: Eight coronoid process fractures were treated by plating and these cases were reviewed retrospectively. Six patients were men and two were women. The average age was 41 years (range: 22-79) at the time of injury. According to Regan's classification, there were five type 2 and three type 3. According to O'Driscoll's classification, there were five anteromedial type and three base type. Open reduction and internal fixation with a plate were performed through a medial approach by splitting of the two heads of the flexor carpi ulnaris. The patients were follow-up for a mean of 15.8 months (range: 6-25). We evaluated the clinical outcomes with using the Mayo Elbow Performance Score. Results: The average active motion of the elbow joint was $120^{\circ}$. The average Mayo Elbow Performance Score was 86.9. There were 5 excellent results, 1 good result and 2 fair results. Summary: Plating through a medial approach of the elbow provided stable fixation and satisfactory union for treating displaced coronoid process fractures with the unstable elbow.