• 제목/요약/키워드: Buttress

검색결과 73건 처리시간 0.028초

영구앵커와 연직 프리캐스트패널을 사용한 절토사면 친환경옹벽공법의 적용사례 (Application for Environment-friendly Retaining Wall Method Composed with Permanent Ground Anchor and Vertical Precast Panel in Cutting Slope Area)

  • 남홍기;정홍섭
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2010년도 추계 학술발표회
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    • pp.87-96
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    • 2010
  • PAP method is a combined measures which consist a anchored retaining wall method with permanent ground anchors and vertical precast concrete panels, step by step on the slope surface. And soil is back filled between slope and vertical precast panels. Therefore, this method is more effective than any other ground anchor reinforcing methods of slope stability, for example cross type concrete block ground anchor or buttress concrete block ground anchor method. Because of increasing effective anchor force and green tree planting.

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Existing concrete dams: loads definition and finite element models validation

  • Colombo, Martina;Domaneschi, Marco;Ghisi, Aldo
    • Structural Monitoring and Maintenance
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    • 제3권2호
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    • pp.129-144
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    • 2016
  • We present a methodology to validate with monitoring data finite element models of existing concrete dams: numerical analyses are performed to assess the structural response under the effects of seasonal loading conditions, represented by hydrostatic pressure on the upstream-downstream dam surfaces and thermal variations as recorded by a thermometers network. We show that the stiffness effect of the rock foundation and the surface degradation of concrete due to aging are crucial aspects to be accounted for a correct interpretation of the real behavior. This work summarizes some general procedures developed by this research group at Politecnico di Milano on traditional static monitoring systems and two significant case studies: a buttress gravity and an arch-gravity dam.

지식근로자 팀효과성의 선행요인 -구성원의 인지적 유사성 vs 속인적 유사성- (The Influence of Cognitive and Demographic Similarities of Knowledge Workers on Team Effectiveness)

  • 강혜련;박숙영
    • 지식경영연구
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    • 제4권2호
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    • pp.1-18
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    • 2003
  • Team-members may have diverse backgrounds and characteristics and such diversity is getting increased in teams in terms of demographics(gender, age, and educations) and capabilities(knowledge, skills, and experiences). A meta-analysis of the last 40 years studies, however, concluded that diversity in teams does not have the consistent main effect on team performances. On the other hand, according to theories of selection and socialization, similarity in values, backgrounds, and experiences buttress the positive and effective working environment. Therefore, we conduct an empirical study in favor of similarity in work teams for the sake of team effectiveness. We investigated the importance of the similarity of team-members on IT team effectiveness. Two aspects of similarity, demographic and cognitive, were considered together. The shared mental model(SMM) was introduced as the representative construct for the cognitive similarity. We found that SMM is more important than the demographic similarities on team effectiveness.

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국산 척추경 나사못 설계를 위한 parametric study (Parametric study on the development of pedicular screw suitable for Korean)

  • 송정일;배성인;최영철;안면환
    • 대한의용생체공학회:학술대회논문집
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    • 대한의용생체공학회 1998년도 추계학술대회
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    • pp.167-168
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    • 1998
  • The purpose of this study is to verify the biomechanical characteristics of the custom-made(our) pedicle screws which are designed the different types of shape, pitch, and profile. The results of experiments for our pedicle screw were summarized. 1) The screw of larger outer diameter showed greater holding strength. 2) The holding strength of cylindrical shaped screw was superior to that of conical shaped screw. 3) The holding strength of buttress shape of thread profile showed superior to that of V-shape. 4) The pull out and holding strength of our pedicle screws was superior to that of commercialized screw (Diapason and CD) which is widely used.

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Zygomaticomaxillary buttress and its dilemma

  • Malaviya, Pallavi;Choudhary, Sandeep
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • 제44권4호
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    • pp.151-158
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    • 2018
  • Zygomatic fractures are the second most common fractures of the facial skeleton, after nasal bone fractures. Due to its uniqueness, the malar bone plays a very important role in maintaining appropriate facial contours. Zygomatic fractures can cause ocular and mandibular functional impairment, along with cosmetic defects. With the help of advanced imaging techniques and various treatment options, the management of zygomatic fractures has become more sophisticated and less invasive. This article discusses zygomatic fractures in detail: their clinical and radiographic features, and the various treatment options available.

Malar Relocation with Reverse-L Osteotomy and Autogenous Bone Graft

  • Yoon, Se Hoon;Jeong, Euicheol;Chung, Jee Hyeok
    • 대한두개안면성형외과학회지
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    • 제18권4호
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    • pp.264-268
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    • 2017
  • The zygomaticomaxillary complex (ZMC) functions as a buttress for the face and is the cornerstone to a person's aesthetic appearance, by both setting the midfacial width and providing prominence to the cheek. Malar deficiency is often acquired by blunt injury incurred in a traumatic accident, resulting in ZMC fracture. A 48-year-old male patient presented a right ZMC fracture after contusion injury by a baseball. He only received conservative management and later he suffered discomfort during mouth opening at the moment of mastication, due to trismus involving the temporomandibular joint. In the current case, we describe a surgical technique, by which the malar body is shifted anteriorly and laterally after combined oblique-vertical osteotomy. The technique presented, eventually restored the former aesthetic position of the malar complex and symmetry, and, moreover, improved mastication function.

Pseudotumor and Subsequent Implant Loosening as a Complication of Revision Total Hip Arthroplasty with Ceramic-on-Metal Bearing: A Case Report

  • Naik, Lokesh Gudda;Shon, Won Yong;Clarke, I.C.;Moon, Jun-Gyu;Mukund, Piyush;Kim, Sang-Min
    • Hip & pelvis
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    • 제30권4호
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    • pp.276-281
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    • 2018
  • Pseudotumors are not uncommon complications after total hip arthroplasty (THA) and may occur due to differences in bearing surfaces of the head and the liner ranging from soft to hard articulation. The most common causes of pseudotumors are foreign-body reaction, hypersensitivity and wear debris. The spectrum of pseudotumor presentation following THA varies greatly-from completely asymptomatic to clear implant failure. We report a case of pseudo-tumor formation with acetabular cup aseptic loosening after revision ceramic-on-metal hip arthroplasty. The patient described herein underwent pseudotumor excision and re-revision complex arthroplasty using a trabecular metal shell and buttress with ceramic-on-polyethylene THA. Surgeons should be aware of the possibility of a pseudotumor when dealing with revisions to help prevent rapid progression of cup loosening and implant failure, and should intervene early to avoid complex arthroplasty procedures.

Iconoclasm and the Capitalistic Spirit of "making things new": a New Print Culture from the English Civil Wars and its Modern Legacy

  • 최재민
    • 영미문화
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    • 제18권1호
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    • pp.23-51
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    • 2018
  • This paper focuses on historical instances of iconoclasm after the Reformation to reveal how iconoclasm had greatly contributed to the formation of the Protestant mindset in the early modern times. During the English civil war, when iconoclastic campaigns and movements were in full tide, the paper argues that the notions of novelty and progress were more positively accepted among radical religious groups. To put it in another way, the paper suggests a different way of looking the formation of Protestant habitus by giving accounts of how iconoclastic impulses spurred diverse religious groups during the civil war to break the mold of conservative thinking and to revolutionize the print culture hitherto based on patronage and served as a buttress for status-quo. From this analysis, then, we are ledto the different portrait of the protestant in the seventeenth century, whose mindset was not quite as solitary and guilt ridden as Max Weber would have us believe.

임프란트 나사형태와 치조골 흡수에 따른 응력분산의 3차원 유한요소법적 분석 (THE THREE DIMENSIONAL FINITE ELEMENT ANALYSIS OF THE STRESS DISTRIBUTION ACCORDING TO THE THREAD DESIGNS AND THE MARGINAL BONE LOSS OF THE IMPLANTS)

  • 김일규;손충렬;장금수;조현영;백민규;박승훈
    • Maxillofacial Plastic and Reconstructive Surgery
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    • 제30권1호
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    • pp.60-71
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    • 2008
  • The objective of this study is to evaluate the stress distribution according to the thread design and the marginal bone loss of a single unit dental implant under the axial and offset-axial loading by three dimensional finite element analysis. The implants used had the diameter of 5mm and 4mm with 13mm in length and prosthesis with a conical type which is 6mm in height and 12mm in diameter. The thread designs were triangular, square and buttress. In the three dimensional finite element model with $15\times15\times20mm$ hexahedron and 2mm cortical thickness, implants were placed with crown to root ratio 7:12, 10:9, 13:6 and 16:3. And additionally the axial force of 100N were applied into 0mm, 2mm and 4mm away from the center of the implants. The results were as follows 1. The maximum von-Mises stress in cortical bone was concentrated to cervical area of implant, and in cancellous bone, apical portion. 2. Comparing the von-Mises stresses in cortical bone of 2mm and 4mm offset loading with central axial loading, it were increased to 3 and 5 times in diameter 4mm implant, and 2 and 4 times, in diameter 5mm implant. 3. The square threads were more effective than the triangular and butress as the longer diameter, the offset loading, and the worse crown to root ratio. 4. The von-Mises stresses were relatively stable until crown to root ratio 13:6, but it was suddenly increased at 16:3. From the results of this study, minimum requirement of crown to root ratio of implant is 2:1, and in the respect of crown to root ratio, diameter and offset loading, square threads are more effective than triangular and buttress threads.

종골의 관절 함몰 골절에서 6.5 mm 해면골 나사와 Steinmann 핀을 이용한 치료의 유용성 (Usefulness of Treatment with 6.5 mm Cancellous Screw and Steinmann Pin Fixation for Calcaneal Joint Depression Fracture)

  • 이기수;강찬;황득수;노창균;이기영
    • 대한족부족관절학회지
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    • 제19권1호
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    • pp.11-17
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    • 2015
  • Purpose: To report the radiographic and clinical results of 6.5 mm cancellous full threaded buttress screw or Steinmann pin fixation to maintain a reduction of calcaneal posterior facet depression fracture. Materials and Methods: From June 2009 to June 2012, 50 consecutive cases with calcaneal joint depression fracture that underwent open reduction and screw or pin fixation were enrolled in this study. A 6.5 mm cancellous full threaded screw was inserted from the posteroinferior aspect of the calcaneal tuberosity to the posterior facet (group A) or Steinman pin was inserted from the posterosuperior aspect of the calcaneal tuberosity to the calcaneocuboidal joint (group B). Both preoperative and postoperative Bohler and Gissane angles were measured radiographically, and American Orthopaedic Foot and Ankle Society (AOFAS) ankle-hindfoot scale on the final follow-up were assessed. Results: The mean age of patients was 44.1 years, and the mean follow-up period was 27.2 months. According to the Sanders classification, 28 cases were type II and 22 cases were type III. In Sanders type II, Bohler and Gissane angles improved significantly from $10.1^{\circ}$ and $126.2^{\circ}$ preoperatively to $27.2^{\circ}$ and $117.1^{\circ}$, respectively, in the immediate postoperative radiograph, and at the final follow-up, $26.6^{\circ}$ and $118.6^{\circ}$, respectively. In Sanders type III, Bohler and Gissane angles improved significantly from $5.0^{\circ}$ and $129.8^{\circ}$ to $29.9^{\circ}$ and $119.3^{\circ}$, respectively, in the immediate postoperative radiograph, and $26.9^{\circ}$ and $120.2^{\circ}$ at the final follow-up. All cases achieved bony union, and the average period until complete union was 13.3 weeks. AOFAS ankle-hindfoot scale was 82.6 in Sanders type II and 77.3 in Sanders type III at the final follow-up. Conclusion: A 6.5 mm cancellous full threaded buttress screw or Steinman pin fixation is a noninvasive treatment method with a merit of being able to maintain the bearing capacity of the posterior facet comparable to plate fixation.