• Title/Summary/Keyword: Progressive Ratio

Search Result 222, Processing Time 0.022 seconds

The Progressive Image Coding using Wavelet Transform (웨이브렛 변환을 이용한 점진적 영상 부호화)

  • 황도연;박정호;유강수;곽훈성
    • Proceedings of the IEEK Conference
    • /
    • 2001.06c
    • /
    • pp.73-76
    • /
    • 2001
  • We propose a new method for image coding that it is based on highly related property between a spatial image and wavelet transform image. The characteristics have an important role in the design of proposed algorithm. This algorithm for image coding is to obtain high compression rate at low bit rate. The other side, the high activity regions are related to significant coefficients which give much influence to image reconstruction, because they mean the important factor to represent the appearance of images such as edge or boundary. For some images with low activity, we can obtain the reconstructed image with near to 30 dB at 150: 1 compression ratio.

  • PDF

Compact Complementary Quadtree for Binary Images (이진 영상을 위한 Compact Complementary Quadtree의 구성)

  • Jo, Yeong-U;Kim, Yeong-Mo
    • The Transactions of the Korea Information Processing Society
    • /
    • v.4 no.1
    • /
    • pp.209-214
    • /
    • 1997
  • In this paper, we propose a new preorder tree method for binary images, named the Compact Complementary Quadtree (CCQ). In the proposed method we use type codes for representing nodes in the quadtree instead of using the symbols G, B, and W. From the experimental results, we have confirmed that the CCQ has a higher compression ratio than of the DF-expression. CCQ can be effectively applied to progressive transmission of binary images such as line drawings, geographical maps, and halftones.

  • PDF

A Study on the Dom-Ino system and Proportion in Le Corbusier′s Houses (Le Corbusier의 주거건축에 나타나는 Dom-Ino시스템과 비례체계에 관한 연구)

  • Cho Sung-Hyun;Kim Chul-Kyu
    • Journal of the Korean housing association
    • /
    • v.15 no.4
    • /
    • pp.107-115
    • /
    • 2004
  • The purpose of this paper is to study on the architectural value in Dom-Ino system. Dom-Ino system by Le Corbusier is a structural system for effective production in terms of physical reproductivity and a modeling system from the view of formal composition. It creates planar grid with a fixed ratio, manipulates the user group, and becomes the basic construction method. Form comes out of geometrical proportion system, and grid-based plan provides regularity and order to elevation planning. Production requires standardization. Indoor space is maintained by uniformed and integrated service facilities. Dom-Ino system was a transitional step of the Modulor system which was created by Le Corbusier in 1945 and composes of and equivalent proportional system. The fact that the numerical proportion system is the one of appropriate design methods implys a progressive concept that architectural configurations are controlled by the technology of that time. And also the system is one of the object type of Corbusier's housing architecture.

Microstrip 8$\times$2 circularly polarized phased array antenna (마이크로스트립 원형 편파 8$\times$2 위상 배열 안테나)

  • 윤재승;이영주;박위상
    • Proceedings of the Korea Electromagnetic Engineering Society Conference
    • /
    • 2000.11a
    • /
    • pp.345-349
    • /
    • 2000
  • A microstrip polarized 8${\times}$2 linear phased array antenna with four 4-bit phase shifters is designed at 10 GHz. The 180$^{\circ}$and 90$^{\circ}$ sections of the phase shifter are of the switched line type, and the rests are of the loaded line type. A 2${\times}$2 sequential sub-array is adopted for a broad axial ratio bandwidth. The construction of the array antenna is of the tile type placing the phase shifters on the same layer containing the feed network. The element spacing is chosen to be 0.45λ$\sub$0/ to exclude the grating lobe. Measurement results show a gain 9.69 dB at broadside and 8.3 dB at the beam-tilt angle of 16$^{\circ}$ by imposing a progressive phase of 90$^{\circ}$.

  • PDF

Fluid-rock Interaction during Contact Metamorphism of the Hwanggangni Formation Geosan, Korea (괴산지역 황강리층의 접촉변성작용에서 유체-암석 간의 상호작용에 관한 연구)

  • Kim, Sangmyung;Kim, Hyung-Shik
    • The Journal of the Petrological Society of Korea
    • /
    • v.5 no.1
    • /
    • pp.21-34
    • /
    • 1996
  • Contact-metamorphosed calc-silicate hornfels of the Hwanggangni formation adjacent to Daeyasan granite in Goesan are characterized by the mineral assemblages. tremolite-clinozoisite-alkali feldspar-calcite, diopside-grossular-vesuvianite, and wollastonite-diopside-phlogopite-grossular-vesuvianite, indicating low $X_{CO_2}$ condition during contact metamorphism. Two trends of fluid-rock interactions are recognized; combination of infiltration and buffering in the outer portion of the aureole and fluid-dominated behavior in the most part of the aureole. Modal abundance of diopside produced during metamorphism was measured in order to estimate fluid/rock ratios and permeabilities with the assumption that equivalent volume of fluids estimated from the fluid/rock ratios flow through the rock body. The calculated fluid/rock rations and permeabilities range from 0.6 to 9 and $10^{-19}$ to $10^{-17}$ meabilities in the calc-silicate hosted contact aureoles and expected values during progressive metamorphism by theories.

  • PDF

Postbuckling response and failure of symmetric laminated plates with rectangular cutouts under uniaxial compression

  • Singh, S.B.;Kumar, Dinesh
    • Structural Engineering and Mechanics
    • /
    • v.29 no.4
    • /
    • pp.455-467
    • /
    • 2008
  • This paper deals with the buckling and postbuckling responses and the progressive failure of square symmetric laminates with rectangular cutouts under uniaxial compression. A detailed investigation is made to show the effects of cutout size and cutout aspect ratio on prebuckling and postbuckling responses, failure loads and failure characteristics of $(+45/-45/0/90)_{2s}$, $(+45/-45)_{4s}$ and $(0/90)_{4s}$ laminates. The 3-D Tsai-Hill criterion is used to predict the failure of a lamina while the onset of delamination is predicted by the interlaminar failure criterion. In addition, the effects of boundary conditions on buckling load, failure loads, failure modes and maximum transverse deflection for a $(+45/-45/0/90)_{2s}$ laminate with and without cutout have also been presented. It is concluded that square laminates with small square cutouts have more postbuckling strength than without cutout, irrespective of boundary conditions.

The synthesis of $Nb_3Sn$ alloy powders by mechanical alloying (기계적 합금화 방법에 의한 $Nb_3Sn$합금 제조)

  • Lee, Sung-Man
    • Proceedings of the KIEE Conference
    • /
    • 1996.11a
    • /
    • pp.464-467
    • /
    • 1996
  • The microstructural evolution during mechanical alloying of Nb and Sn powders, of average composition Nb3Sn, has been investigated by X-ray diffraction(XRD) and scanning electron microscopy(SEM). Observations by SEM showed a progressive change of milling time. From the XRD studies, the structural development with milling time depends on the ball size for a given powder/ball ratio. Using a larger ball of 9.5mm diameter, the elemental powders initially alloy mechanically to form an A15 structure phase, and then amorphised with continued milling. However, in case of milling with a smaller ball of 3.968mm diameter, an amorphous phase is first formed. These results can be understood by considering the dependence of the milling energy on the ball size. The homogeneous stoichiometric $Nb_3Sn$ phase could be easily obtained by heat treatment of a supersaturated solid solution produced by MA. Heat treatment of an amorphous phase formed by MA resulted in the mixture of the $Nb_3Sn$ and $Nb_6Sn_5$ phases.

  • PDF

Change in flame velocity and combustion with inlet air humidity on the spark ignition engine (스파아크 점화기관의 흡기습도에 대한 화염속도 및 연소의 변화)

  • 김문헌;이성열
    • Journal of the korean Society of Automotive Engineers
    • /
    • v.5 no.4
    • /
    • pp.41-46
    • /
    • 1983
  • The influence of inlet air humidity on the flame velocity and combustion of the spark ignition engine were described experimentally by means of the flame velocity measuring apparatus using ion-current. The flame velocity are greatly influenced air fuel ratio and engine speed, and linealy decrease according to the increasing of inlet air humidity. The flame travell curve is very similar to the rate of mass burned and combustion progressive is estimated mostly by only the rate of mass burned curve. The decreasing of the mean flame velocity is about 0.4m/s for increasing of 0.001 specific humidity and we think the reason is mainly decreasing of thermal conductivity.

  • PDF

Evaluation of JPEG2000 Compression Algorithm for Satellite Image

  • Kim, Kwang-Yong;Kim, Kyung-Ok
    • Proceedings of the KSRS Conference
    • /
    • 2002.10a
    • /
    • pp.88-88
    • /
    • 2002
  • Satellite Image archiving system requires large storage and long transmission time. A simple and cheap way of overcoming these limitations is to increase the compression ratio. However this requires a feasibility study for accurate applications. Here, a new still image compression standard is being developed, the JPEG2000. It provides lossless and lossy compression, progressive transmission by pixel accuracy and by resolution, region-of-interest coding, user-defined tiling size, random codestream access and processing etc. In this study, we will briefly introduce the JPEG2000 compression standard which provides a new compression technique based on the wavelet technology and offers better compression ratios, and evaluate the compression ratios of JPEG2000 for satellite image by performing various image quality tests. Also, we will compare brief test result using the commercial remote sensing software.

  • PDF

A Lossless Image Compression using Wavelet Transform with 9/7 Integer Coefficient Filter Bank (9/7텝을 갖는 정수 웨이브릿 변환을 이용한 무손실 정지영상 압축)

  • 추형석;서영천;이태호;전희성;안종구
    • Proceedings of the Korea Institute of Convergence Signal Processing
    • /
    • 2000.08a
    • /
    • pp.253-256
    • /
    • 2000
  • In this paper, we propose the lossless image compression algorithm using the integer wavelet transform. Recently, the S+P transform is widely used and computed with only integer addition and bit-shift operations, but not proper to remove the correlation of smooth images. then we compare the Harr wavelet of the S+P transform with various integer coefficient filter banks and apply 9/7 ICFB to the wavelet transform. In addition, we propose a entropy-coding method that exploits the multiresolution structure and the feedback of the prediction error, and can efficiently compress the transformed image for progressive transmission. Simulation results are compared to the compression ratio using the S+P transform with different types of images.

  • PDF