• Title/Summary/Keyword: Perfect Plastic

검색결과 74건 처리시간 0.025초

"C"자형 만곡비변형의 교정: 건측 비골판줄질(Rasping of Nasal Bone Flap)과 건측 비배측 비중격절제술(Trimming of Dorsal Septum)의 중요성 (Correction of Deviated Nose: Importance of Rasping of Non-affected Side Nasal Bone Flap and Trimming of Non-affected Side Dorsal Septum)

  • 한기환;이민재;김준형;김현지;손대구
    • Archives of Plastic Surgery
    • /
    • 제32권6호
    • /
    • pp.710-716
    • /
    • 2005
  • A total of 21 patients were operated. Via a columellar labial incision, the upper lateral cartilages were separated from the septum. A submucous resection of the septal cartilage was carried out. After rasping the convex lateral nasal wall of the unaffected side, a low-to-low lateral nasal osteotomy was conducted. Along the deviated dorsal line at the bony vault passing the submucous tunnel, a paramedian nasal osteotomy was performed. The convex side of the nasal bone flap was contoured by rasping. The convex side of the "T"-shaped dorsal septum was trimmed. A total direct septal extension graft of the septal cartilage was done and the alar cartilages were suspended to it. The postoperative results were evaluated by photogrammetric analysis processed by a "neon glow" filter in Adobe Photoshop. The distance from the nasal midline to the most deflective point at 5 levels was measured, and the proportion indices were obtained in regard to intercanthal distance. The results revealed improvement in all levels (p < 0.05), although not perfect. In summary, this technique can result in a clinically good-looking in spite of a slight deflection that still exists

액상화 해석을 위한 간단한 구성모델 (A Simple Constitutive Model for Soil Liquefaction Analysis)

  • 박성식;김영수;;김대만
    • 한국지반공학회논문집
    • /
    • 제21권8호
    • /
    • pp.27-35
    • /
    • 2005
  • 액상화에 따른 지반의 과도한 변형으로 인한 피해가 자주 발생되고 있다. 그에 따른 지반의 움직임을 예측하기 위해서는 유효응력 개념에 기초한 수치해석 기법이 요구되어 진다. 본 연구에서는 지진 및 유사한 반복 하중에 따른 수압의 상승을 예측할 수 있는 연성(fully coupled) 유효응력 구성모델인 UBCSAND를 제안하였다. 제안된 모델은 간단한 완전탄소성모델인 Mohr-Coulomb을 변형한 형태로 마찰각(friction angle)과 팽창각(dilation angle)을 점진적으로 증가시킴으로써, 기존의 파괴상태내에서도 연속적인 소성변형 발생을 표현할 수 있다. 항복함수는 전단응력과 평균응력의 비인 $(\sigma'_1-\sigma'_3)/(\sigma'_1-\sigma'_3)$로 나타내며, 응력도의 원점에서 시작하는 무한개의 방사선을 의미한다. 따라서, Mohr-Coulomb의 파괴면과 같은 형태의 무수한 항복면을 가진다. 소성 경화법칙은 등방경화(isotropic hardening)와 이동경화(kinematic hardening)를 혼합한 형태를 이루고 있다. 재하(loading) 및 재재하(reloading)시에는 연속적인 소성 변형이 일어나나, 제하(unloading)시에는 탄성변형을 가정하였다. 제안된 모델은 느슨한 Fraser River 모래를 이용한 직접단순전단시험(Direct simple shear test)결과와 비교하여 검증하였다.

GFRP 보강적층판 및 GFRP rod를 이용한 낙엽송 집성재 접합부의 모멘트저항 성능평가 (Moment Resistance Performance Evaluation of Larch Glulam Joints using GFRP-reinforced Laminated Plate and GFRP Rod)

  • 정홍주;송요진;이인환;홍순일
    • Journal of the Korean Wood Science and Technology
    • /
    • 제44권1호
    • /
    • pp.40-47
    • /
    • 2016
  • 구조용 집성재 라멘 접합부에 일반적으로 사용되는 접합철물을 대신하여 단판과 GFRP (Glass Fiber Reinforced Plastic)를 복합시킨 GFRP 보강적층판과 삽입 접착형 GFRP rod를 접합물로 사용하였다. 이들을 적용시킨 접합부에 대한 모멘트저항 성능평가 결과, 접합철물을 이용한 실험체(Type-1)와 비교하여 GFRP 보강적층판과 GFRP rod 핀을 사용한 실험체의 항복모멘트는 4% 낮게 측정되었으나 회전강성은 29% 높게 측정되었다. 또한 GFRP 보강적층판과 목재(Eucalyptus marginata)핀을 사용한 실험체는 Type-1 실험체와 비교하여 항복모멘트 11%, 회전강성 56% 높게 측정되며 가장 양호한 성능을 나타냈었다. 파괴형상과 완전탄소성 분석을 통해서도 핀에 의한 전단내력으로부터의 취성파괴가 아닌 연성거동을 나타내며, 접합내력이 상승하고 부재의 일체화가 이루어짐을 확인하였다. 반면, GFRP rod를 삽입 접착한 실험체는 접착 불량으로 측정이 불가하거나 접합성능이 매우 낮게 측정되었다.

고추 논재배 시 비가림형태가 생육 및 과실 품질에 미치는 영향 (Effects of Rain-shelter Types on Growth and Fruit Quality of Red Pepper (Capsicum annuum L. var. 'Keummaru') Cultivation in Paddy)

  • 이광재;송명규;김시동;남상영;허정욱;윤정범;김동억
    • 원예과학기술지
    • /
    • 제34권3호
    • /
    • pp.355-362
    • /
    • 2016
  • 본 연구는 고추 논 비가림재배 시 비가림형태가 생육 및 수량에 미치는 영향을 구명코자 수행하였다. 시험품종은 '금마루' 이었다. 비가림형태는 노지(대조구), 간이비가림(2줄재배, 2R), 간이비가림(4줄재배, 4R), 하우스(House) 등 4처리를 하였다. 초장은 House 처리에서 가장 우수하였으며, 엽장과 엽폭은 비가림형태간에 차이가 없었다. 생과중과 건과중은 House > 4R > 2R > 대조구순으로 많았다. ASTA 값은 처리간에 일정한 경향을 나타내지 않았다. 역병, 흰가루병, 세균성점무늬병은 전혀 발생하지 않았고, 탄저병은 노지에서만 발생하였다. 응애, 총체벌레, 담배가루이는 모든 처리에서 발생하지 않았다. 진딧물, 담배나방, 바이러스는 모든 처리에서 동일한 수준으로 발생하였다. 본 연구에서 얻어진 결과는 고추 비가림재배는 건고추 수량 및 상품성 증대뿐만 아니라 병해충의 발생 감소시킬 것으로 기대된다.

분자동력학 해석을 이용한 인덴테이션시 실리콘 내부의 결함구조에 관한 연구 (A molecular dynamics simulation on the defect structure in silicon under indentation)

  • 트란딘 롱;유용문;강우종;전성식
    • Composites Research
    • /
    • 제24권2호
    • /
    • pp.9-13
    • /
    • 2011
  • 본 논문에서는 zinc blende계열의 결정구조를 갖는 실리콘 내부의 결함을 분석할 수 있는 대칭축 파라메터 (Symmetric axis parameter)방법을 이용하여, 탄성 및 소성 변형을 구별하는 방법을 제시하였다. 분자 동력학 해석프로그램인 LAMMPS를 사용하여, 실리콘에 대한 나노인덴테이션 해석을 수행하였다. 구형 인덴터 아래에 발생한 실리콘내부의 결함은 ring crack에서의 threefold 무늬와 전위발생경로를 보여주였다. 또한, 해석결과는 기존의 이론이나, 실험결과와도 일치하는 것을 확인하였다.

신체이미지와 라이프스타일에 대한 연구 (A Study on the Body Image and Life-style)

  • 김선희
    • 복식
    • /
    • 제53권1호
    • /
    • pp.87-98
    • /
    • 2003
  • The purpose of this study was to investigate body image as attitude toward physical appearance, and appearance-management behavior, and to analyze the relationship between body image and life style which affects consumer behavior. The method of the study was survey research by using questionnaires. Subjects were 323 women in their twenties. Statistical analysis methods were frequency, percentage. factor analysis, discrimination analysis, one-way ANOVA, x 2- test, and Duncan's multiple range test. The results of the study were as follows. As for appearance-management behaviors of woman in her twenties. 60.1% of all respondents experienced in diet. 31.6% experienced in plastic operation, 47.4% experienced in skin care, 44.9% experienced in perfect make up, and 84.8% experienced in hair dyeing. The group with high appearance concern showed high body satisfaction. Life-style factors were analyzed into 5 factors. The group with low appearance concern considered active family-focus life factor importantly, the group with middle appearance concern considered social life factor, and the group with high appearance concern considered self-focus life type and conspicuous consumption life factor. A significant difference was found in body image between groups according to social level and demographic characteristics. The female group in the mid twenties who majors in arts and athletics, resides on southern part of Han river, and belongs to high society was analyzed to show high appearance concern and body satisfaction. and many experiences of appearance-management behaviors.

인터넷 기반 복합재 보수 (The Internet-based Composite Repair)

  • 추원식;안성훈
    • 한국복합재료학회:학술대회논문집
    • /
    • 한국복합재료학회 2003년도 춘계학술발표대회 논문집
    • /
    • pp.139-142
    • /
    • 2003
  • As composite materials are gaining wide acceptance in aircraft structure, repair of damaged composite is becoming an important issue. The issues in composite repair include high cost, material interchangeability, water ingression, and structural integrity. To address these problems, researchers have studied on the composite repair in various aspects. In this paper, an Internet-based advisory service (called Repair Advisory Service, RAS) for composite repair is proposed to increase efficiency for repair process. In the RAS system the web browser is used as its user interface, which provides easy access to the service. The RAS server provides web-based tools for failure prediction, Structural Repair Manual (SRM), automated prepreg cutting process, material properties, inventory and knowledge base. The computer codes implemented for repair design estimate the tensile failure and shear failure of repaired structures. The prediction of failure is based on the maximum strain criterion for tensile failure while elastic-perfect plastic shear failure model is applied for interfacial failure. The OEM's SRM is provided in the PDF format for viewing and searching by web browsers instead of looking up paper version SRM. The knowledge base in this site offers a room to share and distribute ideas, memos, publications, or suggestions from the repair engineers. The fabrication tool of RAS reads repair geometry from engineers then generates a CNC toolpath to cut prepreg patches. The RAS service is open to public and available at http://nano.gsnu.ac.kr/. Broad feedback from field technicians and engineers is welcome to improve the usefulness of RAS.

  • PDF

입자강화형 금속복합재료의 강도 예측에 관한 3차원 유한요소 모델의 평가 (An Evaluation of Three Dimensional Finite Element Model on the Strength Prediction of Particles Reinforced MMCs)

  • 강충길;오진건
    • 한국정밀공학회지
    • /
    • 제15권6호
    • /
    • pp.124-138
    • /
    • 1998
  • Particles reinforced MMCs have many advantages over monolithic metals including a higher specific modulus, higher specific strength, better properties at elevated temperatures and better wear resistance. SiC$_p$/A16061 composites have good results in its mechanical properties. This work investigates SiC$_p$/A16061 composites in the microscopic view and compares the analytical results with the experimental ones. The discrepancy of the material properties between the reinforced particle, SiC$_p$, and the matrix material, A16061 appears to be so significant. Especially the coefficient of thermal expansion(CTE) of A16061 is 5 times larger than that of SiC$_p$. Thermal residual stress in MMCs is induced at high temperatures. The shape of particle is various but the theoretical model is not able to consider the nonuniform shape. Particle distribution is not homogeneous in experimental specimen. However, it is assumed to be homogeneous in simulation model. The shapes of particles are assumed to be not only perfect global but hexahedral shapes. The types of particle distribution are two - simple cubic array(SC array) and face-centered cubic array(FCC array).

  • PDF

탄성 변형 영역을 고려한 비정상 평면 변형 이상 공정 이론 (Nonsteady Plane-strain Ideal Forming with Elastic Dead Zone)

  • 이원오;정관수;;강태진
    • 소성∙가공
    • /
    • 제13권6호
    • /
    • pp.540-545
    • /
    • 2004
  • Ever since the ideal forming theory has been developed for process design purposes, application has been limited to sheet forming and, fur bulk forming, to two-dimensional steady flow. Here, application for the non-steady case was performed under the plane-strain condition based on the theory previously developed. In the ideal flow, material elements deform following the minimum plastic work path (or mostly proportional true strain path) so that the ideal plane-stram flow can be effectively described using the two-dimensional orthogonal convective coordinate system. Besides kinematics, fur a prescribed final part shape, schemes to optimize a preform shape out of a class of initial configurations and also to define the evolution of shapes and boundary tractions were developed. Discussions include the two problematic issues on internal tractions and the non-monotonous straining. For demonstration purposes, numerical calculations were made for a bulk part under forging.

Analysis of Facial Asymmetry

  • Choi, Kang Young
    • 대한두개안면성형외과학회지
    • /
    • 제16권1호
    • /
    • pp.1-10
    • /
    • 2015
  • Facial symmetry is an important component of attractiveness. However, functional symmetry is favorable to aesthetic symmetry. In addition, fluctuating asymmetry is more natural and common, even if patients find such asymmetry to be noticeable. However, fluctuating asymmetry remains difficult to define. Several studies have shown that a certain level of asymmetry could generate an unfavorable image. A natural profile is favorable to perfect mirror-image profile, and images with canting and differences less than $3^{\circ}-4^{\circ}$ and 3-4 mm, respectively, are generally not recognized as asymmetry. In this study, a questionnaire survey among 434 medical students was used to evaluate photos of Asian women. The students preferred original images over mirror images. Facial asymmetry was noticed when the canting and difference were more than $3^{\circ}$ and 3 mm, respectively. When a certain level of asymmetry is recognizable, correcting it can help to improve social life and human relationships. Prior to any operation, the anatomical component for noticeable asymmetry should be understood, which can be divided into hard tissues and soft tissue. For diagnosis, two-and three-dimensional (3D) photogrammetry and radiometry are used, including photography, laser scanner, cephalometry, and 3D computed tomography.