• 제목/요약/키워드: transformation region

검색결과 545건 처리시간 0.022초

SiC와 $ZrO_2$를 함유하는 ${Al_2}{O_3}$ 입자복합체의 균열저항거동 : I. 실험 (R-Curve Behavior of Particulate Composites of ${Al_2}{O_3}$ Containing SiC and $ZrO_2$: I. Experiment)

  • 박관수;이승환;이재형
    • 한국세라믹학회지
    • /
    • 제37권4호
    • /
    • pp.359-367
    • /
    • 2000
  • Particulate composites of Al2O3/SiC, Al2O3/ZrO2 and Al2O3/ZrO2/SiC have been fabricated to investigate their R-curve behaviors and toughening mechanisms. Al2O3 containing 30 vol% SiC particles of 3${\mu}{\textrm}{m}$ showed rising R-curve behavior owing to the strong crack bridging by SiC particles. The fracture toughness reached 9.1 MPa {{{{ SQRT {m} }} at the crack length of 1000${\mu}{\textrm}{m}$. On the other hand, ZrO2-toughened Al2O3 had a high flat R-curve since it rose steeply in the short crack region due to the well known transformation toughening. For Al2O3/ZrO2/SiC composites, the R-curve behavior was similar to that of Al2O3/SiC but with slightly higher toughness. The SiC particles in this composite decreased the amount of transformable tetragonal phase to reduce the effect of transformation toughening by 50%. It was also found that the fracture toughness of this composite with two different toughening mechanisms was markedly lower than that estimated by the simple addition of two contributions.

  • PDF

C-Mn TRIP강의 미세조직 변화와 기계적 성질에 미치는 Mn 첨가의 영향 (Effect of Mn Addition on the Microstructural Changes and Mechanical Properties of C-Mn TRIP Steels)

  • 홍호;이오연;송기홍
    • 열처리공학회지
    • /
    • 제16권4호
    • /
    • pp.205-210
    • /
    • 2003
  • Various types of high strength steel sheets were usually used for improving the automobile safety and fuel efficiency by reducing the vehicle weight. The present study aimed to develop the TRIP (transformation induced plasticity) aided high-strength low carbon steel sheets by using a reverse transformation process. The 0.1C-4~8Mn steels were reverse-transformed by slow heating to intercritical temperature region and then furnace cooled to the room temperature. Granular type retained austenite was observed in 4Mn steel and lath type retained austenite was also observed in 6~8Mn steel. The results show that the 6Mn steel under reverse transformed at $625^{\circ}C$ for 6 hrs has maximum elongation up to 39%. The optimum strength-elongation combination was 3,888 ($kg/mm^2{\times}%$) when the 8Mn steel was reverse transformed at $625^{\circ}C$ for 12 h.

항구도시 근대 도시공간 형성에 관한 연구 - 요코하마시 가로 및 운하의 변용을 중심으로 - (A Study on the Formation of Modern Urban Space in Harbor City - Focusing on Transformation of the Urban Street and Canal Space in Yokohama Japan -)

  • 홍지완;김준;유재우
    • 대한건축학회논문집:계획계
    • /
    • 제34권4호
    • /
    • pp.133-140
    • /
    • 2018
  • This study is change of the street space of the port city of Yokohama and the transformation process of the canal. modern port city Yokohama is a region that was responsible for the development of East-West maritime transport routes in Japan in the 17th century and the inland transportation through fishing villages and ports. it has also grown rapidly as a regional port and new port. In particular, through the revitalization of trade between foreign settlements and Japanese residents in the port area, the existing fishing area became a modern port city space. Yokohama went through the following process and grew into a modern port city. The construction of the port harbor and the maintenance of existing logistics functions, the formation of the central horizontal axis through maintenance of the fishing village, the construction of the logistics movement route to the inland area through the construction of the canal, the expansion of the horizon for fire prevention and fire restoration, The formation of a new settlement space according to the movement, the transformation of the existing religious axis by the combination of the elaboration and the introduction of modern transportation, and the spatial connection between the inland cities.

Cloning and Sequence Analysis of a Glyceraldehyde-3-phosphate Dehydrogenase Gene from Ganoderma lucidum

  • Fei Xu;Zhao Ming Wen;Li Yu Xiang
    • Journal of Microbiology
    • /
    • 제44권5호
    • /
    • pp.515-522
    • /
    • 2006
  • A cDNA library of Ganoderma lucidum has been constructed using a Zap Express cloning vector. A glyceraldehyde-3-phosphate dehydrogenase gene (gpd) was isolated from this library by hybridization of the recombinant phage clones with a gpd-specific gene probe generated by PCR. By comparison of the cDNA and the genomic DNA sequences, it was found that the complete nucleotide sequence encodes a putative polypeptide chain of 338 amino acids interrupted by 6 introns. The predicted amino acid sequence of this gene shows a high degree of sequence similarity to the GPD proteins from yeast and filamentous fungi. The promoter region contains a CT-rich stretch, two CAAT boxes, and a consensus TATA box. The possibility of using the gpd promoter in the construction of new transformation vectors is discussed.

Assessment of Factors Influencing Agrobacterium Mediated Transformation in Cucumber (Cucumis sativus L)

  • Sureshkumar P.;Selvaraj N.;Ganapathi A.;Kasthurirengan S.;Vasudevan A.;Anbazhagan V. Ramesh
    • Journal of Plant Biotechnology
    • /
    • 제7권4호
    • /
    • pp.225-231
    • /
    • 2005
  • Five day old cotyledon explants of Cucumber (Cucumis sativus L) cv Poinsett 76 were cocultivated with two Agrobacterium strains (EHA105 and LBA 4404) each carrying GUS as the reporter gene and npt-II as the selection marker gene in the T-DNA region of the vector. Transformed shoots were selected at 150 mg/L kanamycin. A two day cocultivation coupled with $20\;{\mu}M$ acetosyringone increased the frequency (8.2 and 15.4 shoots) of GUS expression in the shoots of transformed plant. Among the two Agrobacterium strains, EHA 105 performed better than LBA 4404 in bringing two-fold increase in transformation efficiency (14%) than LBA 4404 (7.4%). PCR analysis was done to confirm the integration of T-DNA into cucumber genome.

수직선 특징을 이용한 이동 로봇의 자기 위치 추정 (Localization for Mobile Robot Using Vertical Line Features)

  • 강창훈;안현식
    • 제어로봇시스템학회논문지
    • /
    • 제9권11호
    • /
    • pp.937-942
    • /
    • 2003
  • We present a self-localization method for mobile robots using vertical line features of indoor environment. When a 2D map including feature points and color information is given, a mobile robot moves to the destination, and acquires images from the surroundings having vertical line edges by one camera. From the image, vertical line edges are detected, and pattern vectors meaning averaged color values of the left and right regions of the each line are computed by using the properties of the line and a region growing method. The pattern vectors are matched with the feature points of the map by comparing the color information and the geometrical relationship. From the perspective transformation and rigid transformation of the corresponded points, nonlinear equations are derived. Localization is carried out from solving the equations by using Newton's method. Experimental results show that the proposed method using mono view is simple and applicable to indoor environment.

알토 도서관 건축의 유형학적 특성에 관한 연구 (A Study on the Typological Characteristics of Aalto's Library Design)

  • 정태용
    • 한국실내디자인학회논문집
    • /
    • 제19권2호
    • /
    • pp.33-41
    • /
    • 2010
  • This study aims to analyze the typological characteristics of Alvar Aalto's library design. The unique characteristics of Aalto's architecture are the result of accommodating Modern architecture with regional qualities of Finland. Besides this, Aalto's typological approach in design made his color. The library might be the best example for understanding his design approach in that he showed 3 main features of type; wholeness, self-control and transformation. He established architectural types in his 30s through Viipuri public library and developed so-called fan type library plan. Aalto's library type is not a simple copy of exterior and interior form. It acts as a principle of configuration of his library architecture and applied to the building. Therefore, Aalto's library architecture can be recognized as the results of typological design approach in that it shows the transformation of type in according to factors including site, size, region and cultural tradition. In conclusion, Aalto's libraries reveal the typological characteristics in the field of building layout, dynamic space and the effective use of light.

생동도 변환으로 인한 화상의 색오차 보정 (A Compensation of Color Eerror Caused by Dynamic Range Transformation of Images)

  • 장종국;권기룡;안상호;송규익;이건일
    • 전자공학회논문지B
    • /
    • 제33B권4호
    • /
    • pp.124-130
    • /
    • 1996
  • A compensation method of color error resulting from dynamic range transformation of color image is propsoed. The color error is measured using the CIE L a b uniform color space, and the color image is compensated to minimize it. The color error is significant in the dark region of image, which is caused by the lunimance scaling factor is relatively large in that case. In the proposed method, we weight the luminance scaling factor corresponding to luminnce to minimize the error. Because the weighting factor depends on luminace distribution of image, a decisio method of weighting factor using histogram is also proposed.

  • PDF

특징 벡터를 이용한 도로영상의 횡단보도 검출 (Crosswalk Detection using Feature Vectors in Road Images)

  • 이근모;박순용
    • 로봇학회논문지
    • /
    • 제12권2호
    • /
    • pp.217-227
    • /
    • 2017
  • Crosswalk detection is an important part of the Pedestrian Protection System in autonomous vehicles. Different methods of crosswalk detection have been introduced so far using crosswalk edge features, the distance between crosswalk blocks, laser scanning, Hough Transformation, and Fourier Transformation. However, most of these methods failed to detect crosswalks accurately, when they are damaged, faded away or partly occluded. Furthermore, these methods face difficulties when applying on real road environment where there are lot of vehicles. In this paper, we solve this problem by first using a region based binarization technique and x-axis histogram to detect the candidate crosswalk areas. Then, we apply Support Vector Machine (SVM) based classification method to decide whether the candidate areas contain a crosswalk or not. Experiment results prove that our method can detect crosswalks in different environment conditions with higher recognition rate even they are faded away or partly occluded.

이미지 좌표계상의 차선 모델을 이용한 차선 휨 검출 (The Detection of the Lane Curve using the Lane Model on the Image Coordinate Systems)

  • 박종웅;이준웅;장경영;정지화;고광철
    • 한국자동차공학회논문집
    • /
    • 제11권1호
    • /
    • pp.193-200
    • /
    • 2003
  • This paper proposes a novel algorithm to recognize the curve of a structured road. The proposed algorithm uses an LCF (Lane Curve Function) obtained by the transformation of a parabolic function defined on world coordinate into image coordinate. Unlike other existing methods, the algorithm needs no transformation between world coordinate and image coordinate owing to the LCF. In order to search for an LCF describing the lane best, the differential comparison between the slope of an assumed LCF and the phase angle of edge pixels in the LROI (Lane Region Of Interest) constructed by the LCF is implemented. As finding the true LCF, the lane curve is determined. The proposed method is proved to be efficient through various kinds of images, providing the reliable curve direction and the valid curvature compared to the real road.