• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2009년도 추계 학술논문 발표대회
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• pp.9-13
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• 2009

Recently, construction in downtown is often done closely at the adjacent building. In this case, underground construction need to Basement Composite Wall(BCW) construction. However, generally, during the construction process of BCW form works have many problems that are narrow working space and inefficient time consuming. Despite of these problems, there was no quantitative research for the work time of BCM assembly. Therefore, in this study, work time of CBW form assembly in underground construction is identified by the work analysis. The results of this study reveal that buttress work of basement form take lots of time in the entire work process of Basement Composite Wall form assembly.

• 한국재난정보학회 논문집
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• 제12권4호
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• pp.366-372
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• 2016

최근에 콘크리트옹벽의 경우 현장제작 방식에서 프리캐스트 생산에 의한 현장 조립방식으로 기술적 변화가 시도되고 있다. 프리캐스트 옹벽을 상부와 하부로 나누어 각각 생산한 후에 현장에서 조립되는 방법이 사용되고 있다. 그러나, 비교적 높은 부벽식옹벽에 토압이 작용하면 조립부분이 파손될 수 있으며, 대형 재난으로 이어질 수 있다는 문제점이 지적되어 왔다. 따라서, 본 논문에서는 프리캐스트 조인트방법(PC joint method)을 사용한 부벽식 옹벽의 구조적 안정성에 대하여 수치해석적 방법으로 분석하였다. 3가지 높이의 옹벽(7.6m, 8.5m, 10m)에 대하여 배면 토압에 대한 구조적 안정성에 대하여 분석하였다. 옹벽콘크리트에 가해지는 최대 주응력은 23.3~43.2 MPa로서 앵커의 정착주변에서 국부적으로 발생하는 것으로 분석되었다.

• Journal of Chest Surgery
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• 제27권2호
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• pp.153-156
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• 1994

Bentall`s operation for repair of annuloaortic ectasia has been associated with postoperative bleeding and with false aneurysm of the anastomotic site between the coronary orifice and composite graft.Among 5 cases, 2 cases have been operated direct anastomosis between coronary artery and vascular graft.Remained 3 cases have been operated with doughnutlike Teflon felt buttress.The technique of sandwiching the freed button of aortic wall bearing the coronary artery ostium between an outer Teflon felt doughnutlike buttress and the inner composite graft provides a leak-proof anastomosis.We experienced one case reoperation for bleeding at coronary anastomotic site above method.

• 한국지반공학회논문집
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• 제35권11호
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• pp.15-23
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• 2019

본 연구에서는 수치해석을 이용해 격벽형 중력식 2열 합성소일벽(BSCW) 공법의 변위에 대해 분석하고 고찰하였다. 수치해석 모델은 BSCW 앞면 중심부의 현장 변위 데이터를 통하여 검증되었고 세 가지 다른 점토지반(soft, medium, stiff)의 점착력 및 탄성계수에 대한 매개변수 해석을 수행하였다. 또한 Jumbo Special Pattern 공법을 이용한 저면 시멘트 칼럼의 Center-To-Center 간격에 대한 매개변수 해석도 수행하였다. 매개변수 해석 결과, BSCW의 변위는 연약 점토 지반에서 가장 크게 나타났고, 낮은 탄성계수를 가진 지반인 경우 낮은 Center-to-Center 간격이 요구되었다.

• 대한두개안면성형외과학회지
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• 제10권1호
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• pp.1-6
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• 2009

Purpose: This study presents a classification of pure medial and inferior blow-out fracture, and confirms the relationship between the types of fractures, postoperative complications and operative methods. Methods: Sixty patients were treated by transnasal endoscopic reduction with $Medpor^{(R)}$ implantation through subciliary incision and foley catheter insertion into maxillary sinus was done if there was extensive orbital floor fracture. Fractures were classified by number of coronal sections from posterior margin of fossa for lacrimal sac to orbital apex in CT. Type I is defined when the medial wall fracture is over 50% and inferior wall fracture below 50%. Type II, when below 50% medial wall fracture and over 50% floor fracture were present. If there were both over 50%, it was classified as Type III and both below 50% for Type IV. Extreme fracture involving orbital buttress was Type V and postoperative findings in all patients were examined. Results: Type I and V were most common and preoperative findings were more likely to present according to extent of inferior fracture. Diplopia remained in 2 cases after additional insertion of foley catheter, but enophthalmos over 2 mm were presented in 3 cases and diplopia in 3 cases were observed who were not treated with foley catheter. Conclusion: Postoperative complications were increased according to extent of fracture, especially buttress involvement. Additional insertion of foley catheter proved its effectiveness in decreasing postoperative complications.

• 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.

• 한국안전학회지
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• 제27권3호
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• pp.104-110
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• 2012

It is a common practice to design basement walls acting as a one-way slab or plate with idealized boundary conditions, resulting in potentially inefficient design. The walls are often supported by buttress columns and side walls in the vertical direction, thereby acting as a two-way slab. In this study, structural behavior of single-story, three-span basement wall subjected to lateral soil pressure was investigated. Three dimensional finite element analyses were conducted to determine the force distribution on the wall. Based on the numerical studies, a regression analysis was carried out to determine the design values of moments in vertical and horizontal directions as well as shear forces on the wall and design charts are developed. The proposed design method with accompanying design charts would enable practicing engineers to estimate member forces on the wall for preliminary design purpose without resorting to finite element analysis. Numerical examples demonstrated the applicability of the proposed method.

• 대한두개안면성형외과학회지
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• 제19권4호
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• pp.264-269
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• 2018

Background: Orbital resorbable mesh plates are adequate to use for isolated floor and medial wall fractures with an intact bony buttress, but are not recommended to use for large orbital wall fractures that need load bearing support. The author previously reported an orbital wall restoring surgery that restored the orbital floor to its prior position through the transnasal approach and maintained temporary extraorbital support with a balloon in the maxillary sinus. Extraorbital support could reduce the load applied on the orbital implants in orbital wall restoring surgery and the use of resorbable implants was considered appropriate for the author's orbital wall restoring technique. Methods: A retrospective review was conducted of 31 patients with pure unilateral orbital floor fractures between May 2014 and May 2018. The patients underwent transnasal restoration of the orbital floor through insertion of a resorbable mesh plate and maintenance of temporary balloon support. The surgical results were evaluated by the Hertel scale and a comparison of preoperative and postoperative orbital volume ratio (OVR) values. Results: The OVR decreased significantly, by an average of 6.01% (p<0.05) and the preoperative and postoperative Hertel scale measurements decreased by an average of 0.34 mm with statistical significance (p<0.05). No complications such as buckling or sagging of the implant occurred among the 31 patients. Conclusion: The use of resorbable mesh plate in orbital floor restoration surgery is an effective and safe technique that can reduce implant deformation or complications deriving from the residual permanent implant.

• 대한두개안면성형외과학회지
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• 제23권4호
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• pp.171-177
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• 2022

Background: The treatment of zygoma complex fractures is of crucial importance in the field of plastic surgery. However, surgical methods to correct zygoma complex fractures, including the number of fixation sites, differ among operators. Although several studies have compared two-point and three-point fixation, no comparative research has yet been conducted on one-point versus two-point fixation using computed tomography scans of surgical results. Therefore, the present study aimed to address this gap in the literature by comparing surgical results between one-point and two-point fixation procedures. Methods: In this study, we randomly selected patients to undergo surgery using one of two surgical methods. We analyzed patients with unilateral zygoma complex fractures unaccompanied by other fractures according to whether they underwent one-point fixation of the zygomaticomaxillary buttress or two-point fixation of the zygomaticomaxillary buttress and the zygomaticofrontal suture. We then made measurements at three points-the zygomaticofrontal suture, inferior orbital wall, and malar height-using 3-month postoperative computed tomography images and performed statistical analyses to compare the results of the two methods. Results: All three measurements (zygomaticofrontal suture, inferior orbital wall, and malar height) showed significant differences (p< 0.05) between one-point and two-point fixation. Highly significant differences were found for the zygomaticofrontal suture and malar height parameters. The difference in the inferior wall measurements was less meaningful, even though it also reached statistical significance. Conclusion: Using three parameters in a statistical analysis of imaging findings, this study demonstrated significant differences in treatment outcomes according to the number of fixations. The results indicate that bone alignment and continuity can be achieved to a greater extent by two-point fixation instead of one-point fixation.

• 한국건축시공학회지
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• 제9권6호
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• pp.189-195
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• 2009

최근 인구의 도심 집중화 현상이 심화됨에 따라 토지이용의 극대화를 위해 지하공간의 활용이 매우 활발하게 진행되고 있다. 또한 최근 건축물의 지하심도가 깊고 인접건물과 근접시공 되는 경우가 많으므로 건축물의 지하외벽은 슬러리 월 또는 흙막이가시설을 외벽 거푸집으로 사용하고 내측에만 거푸집을 시공하는 방식인 합벽으로 시공되고 있다. 그러나 지하층 합벽 거푸집공사에 대한 원가분석이 건축공사 표준품셈 등에 없는 실정이다. 따라서 본 연구는 지하층 합벽 거푸집 공사의 원가분석을 시행하여 시공단계별 투입원가에 대한 자료를 제공하고자 하였다. 연구결과는 수평목 설치 및 해체는 3%, 거푸집 설치 및 해체는 26%, 보강재 설치 및 해체는 12%, 지지대 설치 및 해체는 42%, 기타 작업은 17% 이다. 정확한 투입원가를 프로세스별 구분하여 정리함으로서 신기술 및 신공법 개발 시 중점을 두어야 하는 포인트를 제시할 것으로 판단된다.