• Title/Summary/Keyword: progressive transmission

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A Progressive Fine Blanking Process Design for Forming of Carrier Plate (캐리어 플레이트 성형을 위한 프로그레시브 파인 블랭킹 공정의 설계)

  • Kim J. D.;Kang J. J.;Hong S. K.;Kim B. J.;Kim H. K.
    • Transactions of Materials Processing
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    • v.14 no.3 s.75
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    • pp.207-214
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    • 2005
  • Blanking process is widely used fur producing various structural parts. However, fine blanking technology is frequently used as a single step blanking operation with clean cut surface of a sheared surface because the fractured surface of parts causes serious problems in the final product and therefore it must be removed by the post-processing in case of the conventional blanking. In the present investigation, a fine blanking process was designed within the framework of progressive die to produce a carrier plate assembled within the auto transmission. Finite element analysis of the shearing behavior at the respective stage of the progressive fine blanking was conducted to validate the designed die parameters. Finally the designed progressive fine blanking process was experimentally evaluated by using the machined die.

Streaming of Solid Models Using Cellular Topology (셀룰러 토폴로지를 이용한 솔리드 모델 스트리밍)

  • Lee, Jae-Yeol;Kim, Hyun
    • IE interfaces
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    • v.16 no.spc
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    • pp.87-92
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    • 2003
  • Progressive mesh representation and generation have become one of the most important issues in network-based computer graphics. However, current researches are mostly focused on triangular mesh models. On the other hand, solid models are widely used in industry and are applied to advanced applications such as product design and virtual assembly. Moreover, as the demand to share and transmit these solid models over the network is emerging, the generation and the transmission of progressive solid models depending on specific engineering needs and purpose are essential. In this paper, we present a Cellular Topology-based approach to generating and transmitting progressive solid models from a feature-based solid model for internet-based design and collaboration. The proposed approach introduces a new scheme for storing and transmitting solid models over the network. The Cellular Topology (CT) approach makes it possible to effectively generate progressive solid models and to efficiently transmit the models over the network with compact model size.

Improvement of Dimensional Accuracy for a Solenoid Valve Case for an 8-Speed Automatic Transmission by Using Multistage Drawing (프로그레시브 공정을 이용한 8단 자동변속기용 솔레노이드 밸브케이스 치수정밀도 향상)

  • Kim, T.H.;Bae, W.B.;Bae, J.H.;Kim, C.
    • Transactions of Materials Processing
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    • v.22 no.8
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    • pp.442-449
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    • 2013
  • The solenoid valve case of an 8-speed automatic transmission plays a role in maintaining the valve seal, which prevents an inflow of foreign substances into the transmission. The seal increases the reliability of the automatic transmission's performance. As a solution to pollution-related problems and to reduce fuel consumption, transmissions are being made with more gears to work more economically and have reduced fuel consumption. These newer transmission require greater dimensional tolerances and need to be manufactured with more precision. In the current study, the design of a multistage drawing considering both the product's height and limit draw ratio (LDR) of the material was performed using both a theoretical analysis and the expertise of industrial experts. The finite element modeling (FEM) simulation was performed using the commercial software, PAM-stamp, and tests of the dimensional measurements for a prototype were performed to verify the optimal progressive process.

Failure analysis of a transmission tower during a microburst

  • Shehata, A.Y.;El Damatty, A.A.
    • Wind and Structures
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    • v.11 no.3
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    • pp.193-208
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    • 2008
  • This paper focuses on assessing the failure of one of the transmission towers that collapsed in Winnipeg, Canada, as a result of a microburst event. The study is conducted using a fluid-structure numerical model that was developed in-house. A major challenge in microburst-related problems is that the forces acting on a structure vary with the microburst parameters including the descending jet velocity, the diameter of the event and the relative location between the structure and the jet. The numerical model, which combines wind field data for microbursts together with a non-linear finite element formulation, is capable of predicting the progressive failure of a tower that initiates after one of its member reaches its capacity. The model is employed first to determine the microburst parameters that are likely to initiate failure of a number of critical members of the tower. Progressive failure analysis of the tower is then conducted by applying the loads associated with those critical configurations. The analysis predicts a collapse of the conductors cross-arm under a microburst reference velocity that is almost equal to the corresponding value for normal wind load that was used in the design of the structure. A similarity between the predicted modes of failure and the post event field observations was shown.

Progressive transmission using optimum bit-ordering of DCT coded image (DCT 부호화 영상의 최적 비트 정렬에 의한 점진적 전송)

  • 채종길
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.19 no.4
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    • pp.679-684
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    • 1994
  • Progressive transmission using optimum bit-ordering of discrete cosine transform(DCT) coded image is proposed to reconstruct a better image in a few bits among all the coded bits at the receiver. It is to transmit the bit gradually to reduce the distrotion of the reconstructed image most by transmitting one more bit. To do this, the power transfer factor(PTF) which is the squared value of difference between the reconstruction level of embedded quantizer and another reconstruction level made by transmitting one more bit is defined. And then, the transmission order of bits is obtained by sorting the PTFs of the coded bits. As a results, the proposed method can reconstruct image having less distortion and better quality at the same bit rate than the conventional zig-zag scan.

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Progressive Region of Interest Coding Using the Embedded Coding Technifque (임베디드 부호화 기법을 이용한 점진적 관심영역 부호화)

  • 최호중;강의성;다나카도시히사;고성제
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.25 no.1B
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    • pp.148-155
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    • 2000
  • In image coding applications such as web browsing and image database searching, it is very useful to quickly view a small portion of the image with higher quality. Region of interest (ROI) coding technique provides the capability to reconstruct the ROI in advance of decompressing the rest of the image, with a smaller number of transmitted bits compared to the case where the entire image is treated with the same priority. In this paper, a progressive ROI coding method using the enbedded coder is presented, and an efficient transmission method for the ROI information. Experimental results show that the proposed progressive ROI coding technique can be effectively used for image coding applications such as web browsing and image database searching system.

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Representation of Three-dimensional Polygonal Mesh Models Using Hierarchical Partitioning and View dependent Progressive Transmission (계층적 분할을 이용한 삼차원 다각형 메쉬 모델의 표현 및 인간 시점에 따른 점진적 전송 방법)

  • 김성열;호요성
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.40 no.6
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    • pp.132-140
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    • 2003
  • In this paper, we propose a new scheme for view-dependent transmission of three-dimensional (3-D) polygonal mesh models with hierarchial partitioning. In order to make a view-dependent representation of 3-D mesh models, we combine sequential and progressive mesh transmission techniques. By setting higher priorities to visible parts than invisible parts, we can obtain good qualify of 3-D models in a limited transmission bandwidth. In this paper, we use a multi -layer representation of 3-D mesh models based on hierarchical partitioning. After representing the 3-D mesh model in a hierarchical tree, we determine resolutions of partitioned submeshes in the last level. Then, we send 3-D model data by view-dependent selection using mesh merging and mesh splitting operations. By the partitioned mesh merging operation, we can reduce the joint boundary information coded redundantly in the partitioned submeshes. We may transmit additional mesh information adaptively through the mesh spritting operation.

Progressive Image Transmission using LOT/CVQ with HVS Weighting (HVS가중치를 갖는 LOT/CVQ를 이용한 점진적 영상 전송)

  • 황찬식
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.18 no.5
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    • pp.685-694
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    • 1993
  • A progressive image transmission (PIT) scheme based on the classified transform vector quantization (CVQ) technique using the lapped orthogonal transform (LOT) and human visual system (HVS) weighting is proposed in this paper. Conventional block transform coding of images using DCT produces in general undesirable block-artifacts at low bit rates. In this paper, image blocks are transformed using the LOT and classified into four classes based on their structural properties and further divided adaptively into subvectors depending on the LOT coefficient statistics with HVS weighting to improve the reconstructed image quality by adaptive bit allocation. The subvectors are vector quantized and transmitted progressively. Coding tests using computer simulations show that the LOT/CVQ based PIT of images is a effective coding scheme. The results are also compared with those obtained using PIT/DCTVQ. The LOT/CVQ based PIT reduces the block-artifacts significantly.

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(A Progressive Image Coding by Wavelet Coefficient Property) (웨이브렛 계수 특성을 이용한 점진적 영상 부호화)

  • 장윤업
    • Journal of the Korea Computer Industry Society
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    • v.3 no.9
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    • pp.1287-1294
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    • 2002
  • The algorithm method for progressive image coding based on discrete wavelet transform presented in a paper. After discrete wavelet transform and extract edge information through edge detection, and then designed efficient coding method more then established embedded coding algorithm using expanded EZW algorithm. Generally, edges have a relatively higher influence on image reconstruction. Occurred DWT on image, and can classify significant coefficients and non-significant coefficients. Using property that edge part has appeared significant coefficient in the paper. Especially, we confirmed that higher frequency sub region on DWT image present homogenous direction property. And on embedded coding, which are effective and well-directed information have higher priority to image reconstruction on transmission. Therefore, our technique algorithm system perform better than that of the conventional method such as progressive image coding application.

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