• Corrosion Science and Technology
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• 제4권1호
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• pp.29-32
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• 2005

A various structural materials are used in construction projects such as a stone, concrete, steel materials. Between of them, concrete are used widely. The compressive strength of concrete is high, and its maintenance and management is comparatively easy. The R.C Building will be superannuated as time passes. This program is generated by propagation of cracks. In order to manage such cracks, time and efforts, expense, etc. are required. In this study, glass sensors were embedding in a model beam and column and leakage of fluorescence and adhesive material was investigated. Further, currents in glass pipe were observed to find the leakage of liquid in glass pipes. Progressive cracks generated by cause the fracture of glass pipes. Therefore, the liquid become to flow and electric current stops, and the cracked part of the member can be found easily. Moreover, the adhesive delays progressive cracking system that responds in air, and the life of a structure can be made to extend. The purpose of this research is to develop of low price sensors that can perform of self-diagnosis in addition to ability of concrete repair concrete to damage.

• Journal of Chest Surgery
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• 제23권3호
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• pp.588-593
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• 1990

The rupture of tracheobronchial tree caused by non penetrating blunt trauma is being increased in incidence though it is still rarely occurred on now Because this type of injury is uncommon, a high index of suspicion should be maintained in all crush injuries involving the chest. Early diagnosis and primary repair not only restore normal lung function but also avoid the difficulties and complications associated with delayed diagnosis and repair. We experienced a case of tracheobronchial rupture caused by non penetrating blunt chest trauma without rib fracture. The patient was a 16 year old male who was a high school student. He was compressed on anterior chest by hand ball goal post being failed down on the morning of admission day. After this accident, he was suffered from progressively developing dyspnea and subcutaneous emphysema on face, neck and anterior chest. The diagnosis, tracheal rupture, was made by chest CT and bronchoscopy. After right thoracotomy, the ruptured site was directly closed by using interrupted suture. Post-operative course was uneventful. Thus we report this case of traumatic tracheal rupture with review of literature.

• Steel and Composite Structures
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• 제49권3호
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• pp.271-280
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• 2023

In this study, the three-dimensional finite element method is used to analyze the behavior of corner cracks in finite-thickness plates repaired with a composite patch. The normalized stress intensity factor at the crack front is used as fracture criterion. Comparison of stress intensity factor values at the internal and external positions of repaired quarter-elliptical corner crack was done, for three repair techniques. The influence of mechanical and geometrical properties of the adhesive layer and the composite patch on the variation of the stress intensity factor (SIF) at the crack-front was highlighted. The obtained results show that the application of double patch leads to a remarkable reduction of SIF at the crack front, compared to facial and lateral repairs.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제29권2호
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• pp.174-181
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• 2007

Today, endoscopic procedures are common in diagnostic and other surgical procedures, with endoscopically enhanced and magnified images permitting surgical access through minimal incisions. This has expanded the treatment options for many difficult anatomic sites, and the endoscope facilitated safe anatomic reduction and fixation. The use of the endoscope may reduce the disadvantages of open fracture repair and should be considered for broad application in the treatment of displaced facial bone fractures. Optical endoscopic magnification minimizes the disadvantages associated with open surgical repair, including the risk of facial nerve injury and external facial scarring, and no postoperative complications have been attributable to the endoscopic approach. This technique was used in 14 patients treated at Ulsan University Hospital, Korea, from September 2004 to August 2006, including six mandibular subcondyle fractures, five blowout fractures and three zygomaticomaxillary complex (ZMC) fractures. Careful preoperative evaluation and proper surgical technique were essential to achieve optimal results in the selected patients.

• Journal of Welding and Joining
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• 제17권1호
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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.

• Structural Engineering and Mechanics
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• 제82권1호
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• pp.17-30
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• 2022

The use of composite patches for the reduction of stresses at the level of the damaged zone in aeronautical structures has experienced rapid expansion given its advantages over conventional mechanical processes (riveting, bolting, etc.). Initially, The research axes in this field were aimed at choosing suitable mechanical properties for the composite and the adhesive, then to optimize the shape of the composite patch in order to ensure good load transfer and avoid having a debonding at the level of the edges essentially for the case of a repair by single side where the bending moment is present due to the non-symmetry of the structure. Our work falls within this context; the objective is to analyze by the finite element method the fracture behavior of a damaged plate repaired by composite patch. Stress reduction at the edge is accomplished by creating a variable angle chamfer on the composite patch. The effects of the crack length, the laminate sequence and the nature of the patch as well as the use of a hybrid patch were investigated. The results show clearly that a beveled patch reduces the stress concentrations in the damaged area and even at its edges. The hybrid patch also ensures good durability of the repair by optimizing its stacking sequence and the location of the different layers according to the fibers orientations.

• 대한두개안면성형외과학회지
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• 제10권2호
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• pp.91-96
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• 2009

Purpose: Frontal sinus fractures are relatively less common than other facial bone fractures. They are commonly concomitant with other facial bone fractures. They can cause severe complications but the optimal treatment of frontal sinus fractures remains controversial. Currently, many principles of treatment were introduced variously. The authors present valid and simplified protocols of treatment for frontal sinus fractures based on fracture pattern, nasofrontal duct injury, and complications. Methods: A retrospective chart review was performed on 36 cases of frontal sinus fractures between January, 2004 and January, 2009. The average age of patients was 33.7 years. Fracture patterns were classified by displacement of anterior and posterior wall, comminution, nasofrontal duct injury. These fractures were classified in 4 groups: I. anterior wall linear fractures; II. anterior wall displaced fractures; III. anterior wall displaced and posterior wall linear fractures; IV. anterior wall and posterior wall displaced fractures. Also, assessment of nasofrontal duct injury was conducted with preoperative coronal section computed tomographic scan and intraoperative findings. Patients were treated with various procedures including open reduction and internal fixation, obliteration, galeal frontalis flap and cranialization. Results: 12 patients are group I (33.3 percent), 14 patient were group II (38.8 percent), group III, IV were 5 each (13.9 percent). Frontal sinus fractures were commonly associated with zygomatic fractures (21.8 percent). 9 patients had nasofrontal duct injury. The complication rate was 25 percent (9 patients), including hypoesthesia, slight forehead irregularity, transient cerebrospinal fluid leakage. Conclusion: The critical element of successful frontal sinus fracture repair is precise diagnosis of the fracture pattern and nasofrontal duct injury. The main goal of management is the restoration of the sinus function and aesthetic preservation.

• 대한두개안면성형외과학회지
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• 제9권2호
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• pp.101-104
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• 2008

Purpose: Diplopia and cosmetically unacceptable enophthalmos are the major complications of blow out fracture. Prolapse of orbital tissue into the sinuses, enlarged orbital volume, atrophy of orbital fat and loss of support of orbital walls play a role in the pathogenesis of enophthalmos. To correct post-traumatic enophthalmos, freeing of incarcerated orbital contents combined with reduction of bony orbital volume and reconstruction of suspensory support of globe is necessary. But remained enophthalmos after surgical treatment is difficult to correct completely. In this case, the authors performed implant insertion for affected orbit and endoscopic orbital decompression for unaffected orbit for correction of late enophthalmos. Method: We reviewed a girl patient with right inferomedial orbital wall blow out fracture, right zygoma fracture treated at our hospital for correction of enophthalmos. An 18-year-old female had sustained posttraumatic enopthalmos. Two surgical management was performed for correction blow out fracture at the other hospital. But residual diplopia, enophthalmos, cheek drooping were found. And then she transferred to our hospital. She had severe enophthalmos(5 mm) also had diplopia and extraocular muscle limitation. We performed operation for correction of enophthalmos. After operation, she showed minimal improvement of diplopia and enophthalmos(3 mm). The authors make plan for operation for correction enophthalmos due to cosmetical improvement. Implant insertion was performed for affected orbit. For unaffected orbit, nasoendoscopic medial orbital wall decompression was proceeded. Result: Correction of enophthalmos was found after operation and was maintained for nine years follow-up. Patient expressed satisfaction for the result. Conclusion: To correct persistant enophthalmos, we could have satisfactory result with orbital wall reconstruction on affected eye and decompression on unaffected eye.

• 한국임상수의학회지
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• 제26권6호
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• pp.644-646
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• 2009

5년령의 체중 4.58 kg 수컷 긴 팔 원숭이가 후지 파행 증상으로 건국대학교 동물 병원에 내원하였다. 신체 검사에서 우측 후지 경골 부위의 연부조직 손상을 보였으며 방사선 사진에서 우측 경골과 비골의 단순 골절이 관찰되었다. 개방형 정복을 실시한 후 tubular dynamic compression plate와 나사를 이용한 고정을 실시하였다. 수술 9주 후 방사선 사진 검사에서 잘 발달된 가골 형성이 골절 부위 피질에서 관찰되었다. 수술 3개월 후 후지 파행 증상을 보이 지 않고 정상 보행이 가능하였다.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제47권5호
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• pp.382-387
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• 2021

Objectives: Zygomatic complex (ZMC) fractures comprise up to 40% of all facial fractures. Misaligned bone fragments and misplaced fixation hardware traditionally detected postoperatively on plain radiographs of the skull might require re-operation. The intraoperative O-Arm (Medtronic, USA) is a three-dimensional (3D) computed tomographic imaging system. Materials and Methods: This retrospective single-center study evaluated the utility of O-Arm scanning during corrective surgeries for ZMC and zygomatic arch (ZA) fractures from 2018 to 2020. Three females and 16 males (mean age, 31.52 years; range, 22-48 years) were included. Fracture instability (n=6) and facial deformity (n=15) were the most frequent indications for intraoperative 3D O-Arm scan. Results: The images demonstrated that all fracture lines were properly reduced and fixed. Another scan performed at the end of the fixation or reduction stage, however, revealed suboptimal results in five of the 19 cases, and further reduction and fixation of the fracture lines were required. Conclusion: Implementation of an intraoperative O-Arm system in ZMC and ZA fracture surgeries assists in obtaining predictable and accurate results and obviates the need for revision surgeries. The device should be considered for precise operations such as ZMC fracture repairs.