• Title/Summary/Keyword: delayed fracture

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Incidental Detection of a Pseudoaneurysm at an Amputation Stump in a Tc-99m HMPAO labeled Leukocyte Scan (Tc-99m HMPAO 표지 백혈구스캔상 대퇴 절주에서 우연히 발견된 가성동맥류)

  • Sohn, Myung-Hee;Jeong, Hwan-Jeong;Lim, Seok-Tae
    • Nuclear Medicine and Molecular Imaging
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    • v.41 no.4
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    • pp.337-338
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    • 2007
  • A 20-year-old man underwent a Tc-99m HMPAO labeled leukocyte scan for the evaluation of an infection at the stump of an AK amputation, which was conducted due to an open communicated fracture of the left lower leg. Blood-flow and blood-pool images demonstrated a pseudoaneurysm with a focus of intense activity medial to the stump, and centered within a large photopenic defect by surrounding hematoma. Delayed image obtained at 3 hours post-injection showed persistent intense and slight increased activity, Contrast angiography confirmed the presence of a pseudoaneurysm arising from a branch of the left superficial femoral artery.

Preanalysis of Hydrogen-induced Delayed Fracture for High Strength Prehent-Treated Steel (고강도 신조질강 냉간단조품의 지연파괴 메커니즘 분석)

  • Lee, J.B.;Kang, N.H.;Park, J.T.;Ahn, S.T.;Park, Y.D.;Choi, I.D.;Cho, K.M.
    • Proceedings of the Korean Society for Technology of Plasticity Conference
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    • 2009.05a
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    • pp.38-39
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    • 2009
  • The precipitate percentage and the spheroidization percentage were analyzed as a function of the tempering temperatures and the alloying elements for high strength preheat-treated steel. The optimum temperature of tempering produced the small precipitates of nano size. The precipitate percentage and the spheroidization percentage were increased with the tempering temperatures. The size of precipitate decreased as the spheroidization of carbon precipitates progressed. The alloying elements such as Cr and Mo reduced the sphereidization temperature.

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Spontaneous Vertebral Reduction during the Procedure of Kyphoplasty in a Patient with Kummell's Disease

  • Hur, Won-Seok;Choi, Sang-Sik;Lee, Mi-Kyoung;Lee, Dong-Kyu;Lee, Jae-Jin;Kim, Kyong-Jong
    • The Korean Journal of Pain
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    • v.24 no.4
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    • pp.231-234
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    • 2011
  • Kummell's disease is a spinal disorder characterized by delayed post-traumatic collapse of a vertebral body with avascular necrosis. Although definitive treatment for Kummell's disease has not been established, it has been reported that percutaneous vertebroplasty or kyphoplasty has shown good results. However, these procedures are not recommended for severely collapsed vertebral bodies because of the risk of cement leakage or technical difficulties. Authors report a rare case of spontaneous reduction in vertebral height by the insertion of a working cannula into the vertebral body in Kummell's disease.

Hydrogen Delayed Fracture of Automotive Multi-Phase Sheet Steels by Hydrogen Charging Condition (수소주입에 따른 자동차용 복합조직강판의 지연파괴 거동)

  • Park, Jae-U;Gang, Gye-Myeong
    • Proceedings of the Korean Institute of Surface Engineering Conference
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    • 2013.05a
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    • pp.87-87
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    • 2013
  • 복합조직강의 미세조직제어를 통한 자동차용 고강도 강판재의 개발이 주요 연구과제로 있다. 하지만 고강도화에 따라 수소에 의한 지연파괴의 문제점이 있어, 이를 규명하고 해결하기 위한 많은 연구가 함께 이루어지고 있다. 본 연구에서는 연구, 개발되고 있는 복합조직강 중 DP강과 TRIP강의 수소취성에 미치는 미세조직의 영향을 분석하고, 수소주입조건에 따른 수소취성 및 지연파괴 거동에 대하여 조사하고자 하였다. 이를 위해 음극전기분해법을 이용, 주입수소량을 달리하여 주입수소가 복합조직강의 지연파괴에 미치는 영향을 분석하였다. Hydrogen determinator를 통해 시편 내 수소량을 측정하였고, 소형펀치시험에 의한 기계적물성 변화를 조사하였다. 또한 파단부위의 넓이와 깊이를 비교측정하였고, 파단면을 SEM으로 관찰하여 수소지연파괴 거동을 평가하고자 하였다.

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Fabrication of SiC Fiber Reinforced Porous Reaction Bonded SiC Composite and Its Mechanical Properties (SiC Fiber 강화 다공질 반응 소결 탄화규소 Composite의 제조 및 기계적 특성)

  • Han, Jae-Ho;Park, Sang-Whan
    • Journal of the Korean Ceramic Society
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    • v.43 no.8 s.291
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    • pp.509-514
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    • 2006
  • In this study, chopped Hi-Nicalon SiC fiber Reinforced Porous Reaction Bonded SiC (RBSC) composites and it fabrication process were developed by using Si melt infiltration process. The porosity and average pore size in fabricated chopped SiC fiber reinforced porous RBSC composites were in the range of $30{\sim}40%$ and $40-90{\mu}m$, which mainly determined by the SiC powder size used as starting material and amount of residual Si in porous composites. The maximum flexural strength of chopped SiC fiber reinforced porous RBSC composite was as high as 80 MPa. The delayed fracture behavior was observed in chopped SiC fiber reinforced porous RBSC composites upon 3-point bending strength test.

Numerical analysis of plasma-sprayed ceramic coatings for high-temperature applications

  • St. Doltsinis, Ioannis;Haller, Kai-Uwe;Handel, Rainer
    • Structural Engineering and Mechanics
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    • v.4 no.6
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    • pp.679-702
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    • 1996
  • The finite element method is employed in conjunction with micromechanical modelling in order to assess the performance of ceramic thermal barrier coatings applied to structural components. The study comprises the conditions of the deposition of the coating by plasma spraying as well as the thermal cycling of the coated component, and it addresses particularly turbine blades. They are exposed to high temperature changes strongly influencing the behaviour of the core material and inducing damage in the ceramic material by intense straining. A concept of failure analysis is discussed starting from distributed microcracking in the ceramic material, progressing to the formation of macroscopic crack patterns and examining their potential for propagation across the coating. The theory is in good agreement with experimental observations, and may therefore be utilized in proposing improvements for a delayed initiation of failure, thus increasing the lifetime of components with ceramic thermal barrier coatings.

Effect of Hydride of the PHWR Pressure Tube on the LBB Evaluation (중수로 압력관의 수화물이 LBB평가에 미치는 영향)

  • Oh, Dong-Joon;Kim, Young-Suk
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.28 no.5
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    • pp.610-616
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    • 2004
  • The aim of this study was to investigate the hydride embrittlement when the LBB evaluation was carried out for the integrity of PHWR Pressure Tubes. The transverse tensile and CCT toughness tests were performed at three hydrogen concentrations while the test temperatures were changed (RT to 30$0^{\circ}C$). Both the transverse tensile and the fracture toughness tests showed the hydrogen embitterment clearly at RT but this phenomenon was disappeared while the test temperature arrived at 25$0^{\circ}C$. Using the DHC test results, the CCL and LBB time were calculated and compared. The hydride embrittlement at the LBB evaluation made the LBB time short definedly. If the operating temperature, DHCV and LBB deterministic parameters such as A and m were known, LBB time could be estimated without the calculation of CCL.

Tracheobronchial Rupture following Blunt Chest Trauma -1 case report- (외상성 기관지 파열 -1례 보고-)

  • 김용한
    • Journal of Chest Surgery
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    • v.23 no.3
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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.

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Effect of delayed time, surface treatment, and repair material on shear bond strength of repaired bis-acryl composite resin (수리된 비스 아크릴 복합 레진의 전단결합강도에 대한 지연시간, 표면처리, 수리 재료의 영향)

  • Park, Ji-su;Lee, Jae-In
    • Journal of Dental Rehabilitation and Applied Science
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    • v.34 no.2
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    • pp.89-96
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    • 2018
  • Purpose: The aim of this study was to evaluate the effect of delayed time, surface treatment, and repair materials on repair of bis-acryl composite resin through comparison of shear bond strength and to evaluate the utility of bis-acryl composite resin repair using polymethyl methacrylate resin. Materials and Methods: A total of 90 bis-acryl composite resin specimens were fabricated and classified into 9 test groups, each of 10 pieces according to delayed time, surface treatment and repair material. The shear bond strength of each specimen was measured using a universal testing machine immediately after fabrication and analyzed using a statistical analysis program (IBM SPSS statistics 20). After the shear bond strength measurement, the fracture surface of the specimen was observed. Results: The highest shear bond strength ($17.54{\pm}3.14MPa$) was observed in the experimental group bonded immediately with a light-curing flowable composite resin using a bonding agent. Conclusion: When repairing bis-acryl composite resin, it is necessary to consider whether to remake according to the delayed time. For effective repair, it is desirable to consider appropriate materials and surface treatment methods according to the site or purpose of use.

Comparison of Results Between Immediate Fixation Group and Delayed Reconstruction Group in Displaced Mid-shaft Fractures of the Clavicle (쇄골 전위성 간부 골절에서 조기 고정술 군과 지연 재건술 군 간의 결과 비교)

  • Kim, Doo-Sub;Rah, Jung-Ho;Yoon, Yeo-Seung;Lee, Chang-Ho
    • Clinics in Shoulder and Elbow
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    • v.12 no.1
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    • pp.61-66
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    • 2009
  • Purpose: Several authors have reported excellent results of delayed reconstruction of non-union & malunion in displaced mid-shaft fractures of the clavicle and these results were equal to that of immediate fixation. But direct comparison between these treatments is rare. We evaluated the results between the immediate fixation group and delayed reconstruction group for treating displaced mid-shaft fractures of the clavicle. Materials and Methods: We studied the results of 18 cases with immediate fixation of displaced mid-shaft fractures of the clavicle and 15 cases with delayed reconstruction of non-union & malunion after conservative management, and these cases were seen from March 2000 to February, 2006. The final postoperative outcome was analyzed according to the clinical outcomes with using the Constant score and the radiological findings of bony union. Results: The constant score was low in the delayed reconstruction group compare to that of the immediate fixation group (p value=0.045). For the pain score & the activities of daily living score, a statistically significant difference was seen between the two groups (p<0.05), but not for the range of motion score & the power score (p>0.05). Radiological findings of bony union were seen for both groups at an average of 8.8 weeks for the immediate fixation group and at an average of 9.8 weeks for the delayed reconstruction group. Conclusion: Though the delayed reconstruction group was shown good clinical and radiological results, the immediate fixation group had a significantly better pain score, a better activities of daily living score and a better Constant score. It is important to choose the initial treatment option for displaced mid-shaft fractures of the clavicle after sufficient explanation to patients about the merits and demerits between these two treatment options.