• 제목/요약/키워드: Block

검색결과 14,792건 처리시간 0.038초

농업부산물을 활용한 사면보호용 식생 블럭 개발 (Development of Planting Block for Protection of Inclined Plane Using Agriculture By-products)

  • 백승출;김영익;성찬용
    • 한국농공학회:학술대회논문집
    • /
    • 한국농공학회 2002년도 학술발표회 발표논문집
    • /
    • pp.201-204
    • /
    • 2002
  • This study is performed to develop of planting block using rice straw ash for Protection of Inclined plane. For the planting, porous concrete block is demanded ability to passing water and air through void of block. In this paper, material used for porous concrete block is cement, rice straw ash, and coarse aggregate(5-10, 10-20, 5-20mm). Planting block size is 23*23*4cm and kinds of planting are Tall fescue, Lespedeza cyrtobotrya and Lespedeza cuneata. The results measured for three months show that possible planting of various kinds for porous concrete block.

  • PDF

Poly-$N^5$-(3-hydroxypropyl glutamine)/Poly (ethylene glycol)block copolymer hydrogel의 합성과 인공피부에의 응용 (Synthesis of Poly-$N^5$-(3-hydroxypropyl glutamine)/Poly (ethylene glycol)block Copolymer Hydrogel and Its Application to the Artificial Skin)

  • 조종수;오상봉
    • 대한의용생체공학회:의공학회지
    • /
    • 제12권1호
    • /
    • pp.57-62
    • /
    • 1991
  • ABA type block copolymers composed of poly($\gamma-benzyl$ L-glutamate) (PBLG) as the A component and poly (ethylene glycol) as the B component were obtained by polymerization of $\gamma-benzyl$ L-gletamate N -carboxyanhydride, initiated by amino groups at both ends of poly(ethylene glycol) . From circular dichroism measurements in ethylene dichloride solution as well as from infrared spectTa measurements in solid state, it was found that the polypep- tide block exists in the a-helical conformation, as in PBLG homopolymer. $Poly-N^5$ (3-hydroxypropyl glutamine) (PHPG)/poly(ethylene glycol)block copolymer hydrogel was obtained by the treatment of PBLG/PBG block copolymer with the mixture of 3-ammine-1-propanol and diamlnooctane. The water content of PHPG/PEG block copolymer hydrogel was about 80wt% when the concentration of crosslinking agent was below 5 mole % per polymer.

  • PDF

서브 블록을 이용한 MPEG-2 인트라 프레임의 시간적 오류 은닉 (Subblock Based Temporal Error Concealment of Intra Frame for MPEG-2)

  • 류철;김원락
    • 대한전기학회:학술대회논문집
    • /
    • 대한전기학회 2005년도 심포지엄 논문집 정보 및 제어부문
    • /
    • pp.167-169
    • /
    • 2005
  • The occurrence of a single bit error in transmission bitstream leads to serious temporal and spatial errors. Because moving picture coding as MPEG-2 based on block coding algorithm uses variable length coding and motion compensation coding algorithm. In this paper, we propose algorithm to conceal occurred error of I-frames in transmission channel using data of the neighboring blocks in decoder. We divide a damaged macroblock of I-frame into four sub blocks and compose new macroblock using the neighboring blocks for each sub block. We estimate the block with minimum difference value through block matching with previous frame for new macroblocks and replace each estimated block with damaged sub block in the same position. Through simulation results, the proposed algorithm will be applied to a characteristic of moving with effect and shows better performance than conventional error concealment algorithms from visual and PSNR of view.

  • PDF

정지영상 및 동영상에서의 효율적인 블록효과 측정방법 (A New Effective Measure of the Block Effect in Still Images and Moving Pictures)

  • 김문성;정진구
    • 한국컴퓨터정보학회논문지
    • /
    • 제7권4호
    • /
    • pp.102-107
    • /
    • 2002
  • 블록 코딩을 기반으로 하는 영상의 압축 부호화는 영상 및 비디오 압축 표준으로 적용되어 왔다. 그런데 영상 복원 시 발생하는 블록효과에 대한 효율적인 측정방법을 찾아보기 힘든 실정이다. 본 논문에서는 서브블록 DCT부호화를 이용한 복원 영상에 대한 객관적인 블록효과 측정방법을 제안한다. 제안한 방법이 주관적인 순위매김과 일치하는 블록효과 측정방법임을 실험결과로서 입증한다 또한 제안한 이 새로운 측정방법은 복원 영상에서 쉽게 그리고 효율적으로 블록효과를 측정하는데 널리 사용될 수 있을 것으로 기대한다.

  • PDF

스테레오 쌍의 전체불일치를 이용한 합리적인 블록과 탐색영역 크기 결정에 관한 연구 (A Study on the determination of proper block and searching area size by using the total disparity of stereo pairs)

  • 김성욱;김신환
    • 한국통신학회논문지
    • /
    • 제24권12B호
    • /
    • pp.2438-2446
    • /
    • 1999
  • 대부분의 블록기반 스테레오 쌍 압축 기술들은 모든 스테레오 쌍에서 가장 일치하는 블록을 찾기 위해 일정한 블록크기와 탐색영역 크기를 사용한다. 그러나 각 스테레오 쌍마다 서로 다른 불일치를 가지기 때문에 모든 스테레오 쌍에 동일한 블록 크기와 탐색영역 크기를 적용하는 것은 효과적이지 못하다. 본 논문에서는 스테레오 쌍의 전체 불일치를 구하는 방법을 제시하고 구하여진 전체 불일치를 사용하여 블록기반 스테레오 쌍의 압축에 적용할 블록 크기와 탐색영역 크기를 결정한다.

  • PDF

OSEK/VDX 기반의 차량 전장용 응용개발도구 설계 및 구현 (Design and Implementation of OSEK/VDX Development Tool for Automotive Applications)

  • 안성호;김재영;김광수
    • 대한임베디드공학회논문지
    • /
    • 제4권2호
    • /
    • pp.84-89
    • /
    • 2009
  • This paper describes the development tool for applications of automotive electronic control unit based on OSEK/VDX. This development tool has a plug-in structure and is written in Java language, because of being based on Eclipse CDT. And also this development tool has another functionality of expansion, which means a special function block can be easily adopted in this development tool. Currently, this development tool consists of five blocks, which are integrated development environment block, fusing program block, system generation block, debugger block, and cross-compiler toolchain block. They have relationship between each other and work for developing OSEK/VDX-based applications. In this paper, we show the functionality of each block of this development tool and its implementation.

  • PDF

전영역 탐색의 고속 움직임 예측에서 기울기 크기와 부 블록을 이용한 적응 매칭 스캔 알고리즘 (Adaptive Matching Scan Algorithm Based on Gradient Magnitude and Sub-blocks in Fast Motion Estimation of Full Search)

  • 김종남;최태선
    • 대한전자공학회:학술대회논문집
    • /
    • 대한전자공학회 1999년도 추계종합학술대회 논문집
    • /
    • pp.1097-1100
    • /
    • 1999
  • Due to the significant computation of full search in motion estimation, extensive research in fast motion estimation algorithms has been carried out. However, most of the algorithms have the degradation in predicted images compared with the full search algorithm. To reduce an amount of significant computation while keeping the same prediction quality of the full search, we propose a fast block-matching algorithm based on gradient magnitude of reference block without any degradation of predicted image. By using Taylor series expansion, we show that the block matching errors between reference block and candidate block are proportional to the gradient magnitude of matching block. With the derived result, we propose fast full search algorithm with adaptively determined scan direction in the block matching. Experimentally, our proposed algorithm is very efficient in terms of computational speedup and has the smallest computation among all the conventional full search algorithms. Therefore, our algorithm is useful in VLSI implementation of video encoder requiring real-time application.

  • PDF

지르코니아 CAD/CAM block의 강도에 관한 연구 (A study on the Flexural strength of zirconia CAD/CAM block)

  • 이정수
    • 대한치과기공학회지
    • /
    • 제30권2호
    • /
    • pp.65-69
    • /
    • 2008
  • Recently, zirconia is widely used in the field of dental ceramics thanks to the proliferation of CAD/CAM systems. Accordingly, different types of zirconia block are being solid in the market. However, there are no precise, objective standards for properties of zirconia. This study concerns the flexural strength of zirconia ceramic for CAD/CAM block. The test specimens used for this study were ZirBlank(Acucera), ZirBlank shade(Acucera), VITA, Cercon(Densply) and Cerasys. The test results suggest that ZirBlank shade block shows the highest flexural strength and density among the zirconia blocks tested. Its flexural strength was $971{\pm}58MPa$ and its density was 99.89%. On the other hand, Cerasys block shows the lowest flexural strength of $576{\pm}36MPa$ and the lowest density of 94.85%. Given all, the density of the specimens is found to be directly proportional to strength and inversely to grain size.

  • PDF

고속 Block Matching 알고리즘에 관한 연구 (A Study on the Fast Block Matching Algorithm)

  • 이인홍;박래홍
    • 대한전자공학회논문지
    • /
    • 제24권4호
    • /
    • pp.667-674
    • /
    • 1987
  • In this paper an effective block matching algorithm is proposed to find the motion vector. There are two approaches to the estimation of the motion vector in MCC (motion compensated coding), i.e., pel(pixel element) recursive algorithm and block matching algorithm. The search algorithm in this paper is based on the block matching method. The advantage of a proposed algorithm using integral projections is the reduction of the computation time. While the conventional block matching methods have to be computed in 2-dimensional arrays, the proposed algorithm using integral projections can be computed in 1-dimensional arrays. In comparison with conventional block matching methods, a computer simulation shows that though the prediction error increases 0.23 db, it is not detectable for human eyes and the average reduction ratio of computation time obtained from the proposed algorithm is about 3-4.

  • PDF

Buerger환자 43명의 치료 경험 (Treatment of 43 Patients with Buerger's Disease)

  • 전재규;장영호;정정길
    • The Korean Journal of Pain
    • /
    • 제9권1호
    • /
    • pp.114-119
    • /
    • 1996
  • Buerger's disease is a nonatherosclerogic occlusive inflammatory disease of medium and small arteries, and veins, of unknown cause. It occurs predominantly in young males who are habitual tabacco users. These patients often complain of painful ulcerations of their digits. The care of this disease is very difficult when the treatment is delayed. Consequently, early treatments are most important to patients with Buerger's disease. This disease can be treated with sympathetic block such as stellate ganglion block for upper extremities and lumbar epidural block, and lumbar sympathetic block for lower extremities. Intravascular regional sympathetic block can be another method of treatment. However, discontinuation of smoking is the most basic and essential treatment for Buerger's disease. We treated 43 Buerger's disease patients with stellate ganglion block and laser therapy. The treatment was not effective for three patients who definitely required amputation.

  • PDF