• Journal of Trauma and Injury
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• v.26 no.3
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• pp.218-221
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• 2013

A patella sleeve fracture is a type of avulsion fracture in which a small osseous fragment gets, along with a sleeve of periosteum and cartilage, is pulled off from the patella. The avulsed sleeve of cartilage and periosteum is not apparent on plain radiographs, which can result in a missed diagnosis or an underestimate of the extent of injury. An avulsion or sleeve fracture of the patella in a child can occur at the superior or the inferior pole of the patella. However, most reported cases of sleeve fractures involve the inferior patellar pole, with fractures involving the superior patellar pole being very rare. The authors report a case of a sleeve fracture of the superior pole of the patella in an adolescent; the fracture was diagnosed with magnetic resonance imaging (MRI) and was treated with surgery after early diagnosis. The course was uneventful, and the outcome was excellent.

• Journal of Korean Orthopaedic Sports Medicine
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• v.8 no.2
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• pp.121-124
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• 2009

Patellar fractures in children represent less than 2% of all patellar fractures including adults, and occur about 1% of all pediatric fractures. Because of property of the growing patella, osteochondral or avulsion fractures are more common in children and the most common type of patella fracture in children is sleeve fracture. Avulsion or sleeve fractures of the patella in children can occur at the superior or inferior pole of the patella. Most reported cases of sleeve fracture are involving the inferior patellar pole, but involving the superior patellar pole is very rare. We experienced a case of sleeve fracture occurred at the superior pole of the patella in a sixteen-year-old boy and report this case with literature review.

• Journal of The Korean Society of Agricultural Engineers
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• v.46 no.1
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• pp.41-51
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• 2004

FRP re-bar in concrete structures could be used as a substitute of steel re-bars for that cases in which aggressive environment produce high steel corrosion, or lightweight is an important design factor, or transportation cost increase significantly with the weight of the materials. But FRP fibers have only linearly elastic stress-strain behavior; whereas, steel re-bar has linear elastic behavior up to the yield point followed by large plastic deformation and strain hardening. Thus, the current FRP re-bars are not suitable concrete reinforcement where a large amount of plastic deformation prior to collapse is required. The main objectives of this study in to evaluate the tensile behavior and the fracture mode of hybrid FRP re-bar. Fracture mode of hybrid FRP re-bar is unique. The only feature common to the failure of the hybrid FRP re-bars and the composite is the random fiber fracture and multilevel fracture of sleeve fibers, and the resin laceration behavior in both the sleeve and the core areas. Also, the result of the tensile and interlaminar shear stress test results of hybrid FRP re-bar can provide its excellent tensile strength-strain and interlaminar stress-strain behavior.

• Journal of the Korea institute for structural maintenance and inspection
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• v.16 no.1
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• pp.27-34
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• 2012

The objective of this study is to evaluate the stiffness of mortar-filled sleeve bar splice using estimation method of failure mode in the sleeve reinforcement splice. To attain this goal, we analyzed the test results of 261 actual-sized mortar-filled sleeve splice specimens. The study results showed that the estimation method of the failure mode in mortar-filled sleeve bar splice made an effective estimate of the stiffness in this bar splice with the exception of specimens with SD500 bars and smooth pipe sleeve. Especially, of the specimens with cast sleeve or uneven pipe sleeve in the range of reinforcement fracture using the estimation method of the failure mode in mortar-filled sleeve splice, specimens over 98% with SD400 bars and all specimens with SD500 bars had the stiffness capacity of higher than "A" class of AIJ code in monotonic loading. In addition, of the specimens in the range of reinforcement fracture using the estimation method of the failure mode in mortar-filled sleeve splice, all specimens with SD400 bars and SD500 bars had the stiffness capacity of higher than "A" class of AIJ code in cyclic loading.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.21 no.11
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• pp.1036-1041
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• 2008

According to previous report, aged sleeves of old transmission line showed several defaulted installation patterns, which was biased or corrosive-fractured of steel sleeve installed cases. These defects can cause serious accidents such as rapid increasing of sag or falling out of overhead conductor from sleeves. Consequently, the defects lead to the major power outage. Corrosion of steel sleeve is a typical defect by aging of sleeves. And it occupied almost 25 percent of investigated aged sleeves. This paper studied thermal properties and tension for ACSR conductor in case of fractured steel sleeve model by corrosion. The temperature distribution within overhead conductor has a specific gradient. Thermal properties of splice connectors(sleeve and clamp) showed normal behavior. However, mechanical properties were worse than normal sleeves. The detailed results were presented in the text.

• Journal of Welding and Joining
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• v.17 no.1
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• pp.82-87
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• 1999

The basic remote sleeve repair-welding technology by the pulsed Nd:YAG laser for increasing the lifetime of the steam generator tube in a nuclear power plant has been developed. The relationship between the connection width and welding parameters have been investigated for the fundamental research to apply the sleeve-repair-welding technique to the nuclear industry. The Inconel 600 tube and Inconel 690 sleeve used for high temperature and high pressure service were welded as round lap welding by Nd:YAG laser. It was observed that the tensile shear strength, 340MPa of the welded specimen is equivalent to about 60% of that of the base metal (Inconel 600), 550MPa. The difference between the hardness of the base metal and that of the laser welds was about 10%. Ductile fracture was partly occurred in the weld but the cracking has not been observed. In spite of absence of the crack, the strength of welds was not sufficient in terms of the tensile shear strength.

• Journal of Korean Foot and Ankle Society
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• v.27 no.2
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• pp.39-42
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• 2023

A ruptured Achilles tendon at the calcaneus attachment, which does not include a bone that can be fixed, is called 'sleeve avulsion'. A small amount of tendon in the calcaneal region can be sutured to the proximal portion of the ruptured Achilles tendon or insufficient bone to be fixed. Hence, tendon-bone healing is expected, but the results are not good compared to other parts of the tear. The incidence of Achilles tendon rupture is 7 to 40 per 100,000 patients, and 25% of patients undergo direct suture or reconstruction surgery, and 7.6% of patients with sleeve avulsion injuries undergo surgery. Surgical treatment may be a better choice for Achilles tendon sleeve avulsion because no successful case of conservative treatment has been reported. Distal wounds above the ruptured tendon adjacent to the bony eminence can have wound healing problems because of the thin, soft tissue and hypovascularity. An appropriate surgical method must be selected for each patient.

• Clinics in Shoulder and Elbow
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• v.9 no.2
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• pp.207-210
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• 2006

We presented a case of posteriorly displaced fracture of the distal clavicle in Child. The closed reduction was failed due to posteriorly displaced proximal fragment and interpositon of trapezius muscle and periosteum. We found that periosteal sleeve and coracoclaviclar ligament and acromioclavicular ligament was intact. The open reduction should be considered for the treatment of the irreducible posteriorly displaced fracture of the distal clavicle in child.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.41 no.11
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• pp.1021-1033
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• 2017

In this study, an optimum process to improve structural integrity was established by investigating effect of the process variables on fatigue lifetime of steel-sleeve repair welds in buried gas pipeline. Residual stresses in the repair welds were derived through sequentially-coupled temperature-stress analysis using ABAQUS, which is a commercial finite element analysis program. In addition, variations of operating stresses were derived by finite element linear elastic stress analysis. Fatigue lifetimes of the steel-sleeve repair welds were evaluated by substituting the derived weld residual stresses and operating stress variations into the structural stress/fracture mechanics approach as input. Parametric study using finite element analysis and fatigue assessment for various repair welding process variables were carried out to investigate the effects of the process variables on the fatigue lifetime. Finally, based on the effects of the process variables on the fatigue lifetime, an optimal process to minimize the welding time and economic costs and to improve the fatigue lifetimes was derived.

• Journal of Chest Surgery
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• v.18 no.3
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• pp.497-505
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• 1985

Bronchoplastic techniques represent the ideal surgical therapy for benign endobronchial tumors as well as tumors of low-grade malignant potential, such as bronchial adenomas, and for repair of traumatic airway injuries and benign strictures. This approach is also applicable to a select group of patients with carcinoma of the lung, with long-term survival being comparable to that achieved by standard pneumonectomy. Five bronchoplastic procedures were performed at Department of Thoracic and Cardiovascular Surgery, Seoul National University Hospital during 7 months periods from Dec. 1984 to Jun. 1985. Of the 5 patients, 3 patients were male and 2 patients were female and ages ranged from 8 years to 55 years old. The final diagnoses of 5 patients were as followed; traumatic bronchostenosis, endobronchial tuberculoma, carcinoid tumor, tuberculous bronchostenosis and traumatic bronchial fracture. Operative procedures of 5 patients were as followed; resection and end-to-end anastomosis of right main bronchus, left lower lobectomy and wedge resection of bronchus, left upper sleeve lobectomy, right middle and lower sleeve lobectomy and resection and end-to-end anastomosis of left main bronchus. And 2 lungs and 3 lobes could be preserved by these bronchoplastic procedures. There was no post-operative complication or mortality and all patients are being followed up without specific problem.