• 제목/요약/키워드: Improved Shape

검색결과 1,596건 처리시간 0.03초

부순모래의 표면형상이 모르터의 물성에 미치는 영향 (A Study on the Influence of the Physical Properties of Mortar on Surface Shape of Crushed Sand)

  • 이승한;김종인;윤용호;한형섭
    • 한국콘크리트학회:학술대회논문집
    • /
    • 한국콘크리트학회 1997년도 가을 학술발표회 논문집
    • /
    • pp.51-56
    • /
    • 1997
  • This study is aimed for investigating the influence of mortar on improved of surface shape of crushed sand, and analyzing the physical properties of fresh state and hardened state. By the test results, it was found that the flow value and bleeding ratio was increased, but the change of flow value according to time was decreased with the improved surface shape of crushed sand. Also, comparing improved of surface shape of crushed sand with not improved of surface shape of crushed sand on strength, compressive strength is about the same and flexural strength decrease in case of improved of surface shape of crushed sand.

  • PDF

개량 Douglas-Peucker 알고리즘 기반 고속 Shape Matching 알고리즘 (Fast Shape Matching Algorithm Based on the Improved Douglas-Peucker Algorithm)

  • 심명섭;곽주현;이창훈
    • 정보처리학회논문지:소프트웨어 및 데이터공학
    • /
    • 제5권10호
    • /
    • pp.497-502
    • /
    • 2016
  • Shape Contexts Recognition(SCR)은 도형이나 사물 등의 모양을 인식하는 기술로 문자인식, 모션인식, 얼굴인식, 상황인식 등의 기반이 되는 기술이다. 하지만 일반적인 SCR은 Shape의 모든 contour에 대해 히스토그램을 만들고 Shape A, B 비교를 위해 추출된 contour를 1:1 개수대로 매핑함으로써 처리속도가 느리다는 단점이 있다. 따라서 본 논문에서는 Shape 모양에 따라 윤곽선을 찾고 개량 DP 알고리즘 및 해리스코너 검출기를 이용하여 contour를 최적화시킴으로써 간략하면서도 더 효과적인 알고리즘을 만들었다. 이렇게 개선된 방법을 사용함으로써 기존방법보다 처리 수행속도가 빨라짐을 확인하였다.

와동형태가 5급 와동 수복물의 변연누출에 미치는 영향 (THE EFFECT OF CAVITY CONFIGURATION ON MARGINAL LEAKAGE OF CLASS 5 RESTORATION)

  • 박정길;허복;이희주
    • Restorative Dentistry and Endodontics
    • /
    • 제26권2호
    • /
    • pp.162-170
    • /
    • 2001
  • The purpose of this study was to investigate the effect of cavity configurations on the marginal leakage of class 5 glass ionomer cement and composite resin restorations. Four types of cavities such as saucer shape. notch shape. combined shape(notch shape occlusally and saucer shape gingivally). and U shape were prepared on the buccal and lingual surfaces of 80 extracted premolars(40 cavities for each shape). Occlusal cavity margins were placed at enamel and cervical margins were placed at dentin. 10 cavities of each shape were restored with Ketac Fil as a conventional glass ionomer cement. Fuji II LC improved as a resin modified glass ionomer cement, Z 100 as a hybrid composite resin. and Tetric Flow as a flowable composite resin (40 cavities for each material). After thermocycling, teeth were immersed in 5% basic fuchsin solution for 6 hours and sectioned longitudinally in a buccolingual direction through the center of the restoration. The dye penetrations at the tooth restoration interface were examined by stereomicroscope. The Result were as follows 1. In saucer shape, notch shape and combined shape, composite resin restorations showed lesser leakage than glass ionomer restorations(p<0.05) and in U shape. Tetric Flow showed the least marginal leakage and others were decreased as Z 100. Fuji II LC improved, Ketac Fil in that order. There were statistically significant difference between Tetric Flow and Fuji II LC improved. Ketac Fil and between Z 100 and Ketac Fil(p<0.05). 2. In Ketac Fil restoration group, saucer shape showed the highest marginal leakage and U shape showed the least marginal leakage and others were decreased as notch shape, combined shape in that order. There were statistically significant difference between saucer shape and combined shape, U shape and between notch shape and U shape(p<0.05). 3. In Fuji II LC improved restoration group, U shape showed the least marginal leakage. There were statistically significant difference between U shape and other three shapes(p<0.05). 4. The cavity configuration had no significant effect on marginal leakage of composite resin restorations(p>0.05).

  • PDF

Mobile Palmprint Segmentation Based on Improved Active Shape Model

  • Gao, Fumeng;Cao, Kuishun;Leng, Lu;Yuan, Yue
    • Journal of Multimedia Information System
    • /
    • 제5권4호
    • /
    • pp.221-228
    • /
    • 2018
  • Skin-color information is not sufficient for palmprint segmentation in complex scenes, including mobile environments. Traditional active shape model (ASM) combines gray information and shape information, but its performance is not good in complex scenes. An improved ASM method is developed for palmprint segmentation, in which Perux method normalizes the shape of the palm. Then the shape model of the palm is calculated with principal component analysis. Finally, the color likelihood degree is used to replace the gray information for target fitting. The improved ASM method reduces the complexity, while improves the accuracy and robustness.

일반 구조물에 대한 형상 최적화 시스템의 개발 (Development of Shape Optimization System for General Structures)

  • 한석영
    • 한국공작기계학회:학술대회논문집
    • /
    • 한국공작기계학회 2000년도 춘계학술대회논문집 - 한국공작기계학회
    • /
    • pp.304-309
    • /
    • 2000
  • Growth-strain method was used for shape optimization of general structures. It was verified that the growth-strain method is very effective for shape optimization of solid structures in previous papers, but It could not provide reasonable optimized shape for structures with holes inside. The purpose of this study is to improve the growth-strain method for shape optimization of two- and three- dimensional structures. In order to improve, the problems occurred as the growth-strain method was applied to general structures were examined, and then the improved method was suggested. Finally, an automatic shape optimization system was built up by the improved growth-strain method with finite element method. The effectiveness and practicality of the developed shape optimization system was verified by some examples.

  • PDF

유동해석을 통한 소형 터보압축기 성능 개선 설계에 관한 연구 (A STUDY ON IMPROVED DESIGN OF SMALL SIZE TURBO-COMPRESSOR USING COMPUTATIONAL FLUID ANALYSIS)

  • 김승민
    • 한국전산유체공학회:학술대회논문집
    • /
    • 한국전산유체공학회 2010년 춘계학술대회논문집
    • /
    • pp.142-146
    • /
    • 2010
  • This study presents the design of small size turbo-compressor to increase the performance using computational fluid analysis. A three dimensional computation was conducted changing the main parameters of impeller blade and diffuser shape, respectively, and the design was performed on a basis analysis of result of that. As a result, the Improved shapes show the increase of efficiency in comparison with the existing shape. This study will be used as useful reference data to establish the design concept of the small size turbo-compressor and to improve its performance.

  • PDF

벽돌형 개량메주의 품질수명 (Studies on the Shelf-life of the Brick Shape Improved Meju)

  • 박충균;남주현;송형익
    • 한국식품과학회지
    • /
    • 제22권1호
    • /
    • pp.82-87
    • /
    • 1990
  • 벽돌형 개량메주의 품질수명을 측정할 목적으로 벽돌형 개량메주를 제조하고 포장상태와 비포장상태로 구분하여 $30^{\circ}C$ 항온기 내에서 저장하면서 저장기간 중 메주의 성분변화를 측정했으며 또한 저장기간을 달리하여 간장담금을 한 후 $25^{\circ}C$ 에서 90일간 숙성시키면서 숙성기간 중 간장덧액의 성분변화와 식미 관능검사를 통하여 개량메주의 저장기간이 간장의 품질에 미치는 영향을 비교 검토하였다. 개량메추의 저장 중 성분의 변화가 큰 것은 $NH_2-NH_3-N$ 및 protease 역가였으며 그 중 protease 역가가 간장발효의 중요한 성분일 뿐 아니라 저장 중 가장 큰 변화를 나타내어 품질평가의 가장 좋은 지표성분임을 입증하였다. 간장덧액의 품질 측정에서 저장기간이 긴 메주의 간장이 갈색도는 증가했으나 향미와 맛 그리고 기호도 종합평점에서 뒤졌으며 전반적으로 protease 역가가 높은 메주의 간장이 높은 기호도를 나타내어 품질이 우수함을 알 수 있었다. 벽돌형 개량메주는 낱알형에 비하여 protease 역가가 낮았으나 저장기간 중 역가의 감소가 완만하게 진행되어 저장수명이 더 긴 것으로 나타났다. 본 실험조건에서 벽돌형 개량메주의 품질은 저장 30일째가 가장 좋았으며, 품질평가의 지표가 되는 pretense 역가(O.D. at 600nm/g)는 그 후 서서히 감소되어 저장 180일째에 포장과 비포장이 각각 205와 207을 유지하였으며 따라서 낱알형 개량메주의 기준을 적용할 때 벽돌형 개량메주의 품질수명은 180일 정도인 것으로 추정되었다. 또한 포장상태 저장은 벽돌형 개량메주의 품질향상에 별다른 효과가 인정되지 않았다.

  • PDF

브러시없는 직류 선형 모터의 고정자 형상 최적 설계 (The optimum geometric design of stators for brush less DC linear motors)

  • 최문석;김용일;이상락
    • 한국정밀공학회:학술대회논문집
    • /
    • 한국정밀공학회 1995년도 추계학술대회 논문집
    • /
    • pp.1173-1176
    • /
    • 1995
  • We design and analyze two type stators for brushless DC linear motors by the experiment and the computational analysis. For a U-shape stator, the maximum manetic flux density by the finite element method(FEM) is large than that by the experiment by 1.0~2.2%. The result by the FEM is so accurate that it can be applied to the geometric design for the optimization. To increase the maximum magnetic flux density, we suggest an improved stator and analyze it by the 3-D and 2-D models. The maximum magnetic flux density of the improved stator is large than that of the U-Shape stator by 2.7%. Considering the size of the improved stator and maximum magnetic flux density, we determine that the optimized thickness is 5mm for a given specification.

  • PDF

형상 최적화를 위한 성장-변형률법의 적용 (Application of the Growth-Strain Method for Shape Optimization)

  • 이경래
    • 한국생산제조학회지
    • /
    • 제8권2호
    • /
    • pp.27-34
    • /
    • 1999
  • The growth-strain method was used for shape optimization, which carries out the optimization by distributing uniformly the distributed parameter such as von Mises stress and shear strain energy density. Shape optimization is carried out by iteration of stress analysis and growth strain analysis. In this study, the effect of growth ratio in the method was investigated and then the range of the adequate value of the growth ratio was determined. Also the growth-strain method was improved by applying the linear PID control theory in order to control volume required by a designer. Finally, an automatic shape optimization system was built up by the improved growth-strain method with a commercial software using finite element method. The effectiveness and practicability of the developed shape optimization system was verified by some examples.

  • PDF

재생골재 입형이 재생골재콘크리트의 압축강도와 슬럼프에 미치는 영향 (The Effects of Recycled Aggregate Shape on Compressive Strength and Slump of Recycled Concrete)

  • 정지용;심종우;이세현
    • 한국콘크리트학회:학술대회논문집
    • /
    • 한국콘크리트학회 2006년도 춘계 학술발표회 논문집(II)
    • /
    • pp.97-100
    • /
    • 2006
  • The efforts have improved the absorbtion that in order to high the quality of recycled aggregates, and the shape. For the shape of recycled aggregates, the shape of usually aggregates can affect the strength of concrete in an indirect way. So that, in the study, effects is investigated the shape of recycled aggregates that affects the compressive strength and slump. In the result, the a improved shape have a beneficial effect on compressive strength and slump for of a high quality recycled aggregate, and these appear a larger effects in unit water ; $175kg/m^3$ or specified strength ; 24MPa.

  • PDF