The Experts below are selected from a list of 60 Experts worldwide ranked by ideXlab platform

Roxana Smarandache - One of the best experts on this subject based on the ideXlab platform.

  • ITW - Free Pseudodistance Growth Rates for Spatially Coupled LDPC Codes over the BEC
    2018 IEEE Information Theory Workshop (ITW), 2018
    Co-Authors: Cunlu Zhou, David G. M. Mitchell, Roxana Smarandache
    Abstract:

    The minimum pseudoweight is an important parameter related to the decoding performance of LDPC codes with iterative message-passing decoding. In this paper, we consider ensembles of periodically time-varying spatially coupled LDPC (SC-LDPC) codes and the pseudocodewords arising from their finite graph covers of a fixed degree. We show that for certain (J,K)-regular SC-LDPC code ensembles and a fixed cover degree, the typical minimum pseudoweight of the unterminated (and associated tail-biting/terminated) SC-LDPC code ensembles grows linearly with the Constraint (Block) length as the Constraint (Block) length tends to infinity. We prove that one can bound the the free pseudodistance growth rate over a BEC from below (respectively, above) using the associated tail-biting (terminated) SC-LDPC code ensemble and show empirically that these bounds coincide for a sufficiently large period, which gives the exact free pseudodistance growth rate for the SC-LDPC ensemble considered.

  • Free Pseudodistance Growth Rates for Spatially Coupled LDPC Codes over the BEC
    2018 IEEE Information Theory Workshop (ITW), 2018
    Co-Authors: Cunlu Zhou, David G. M. Mitchell, Roxana Smarandache
    Abstract:

    The minimum pseudoweight is an important parameter related to the decoding performance of LDPC codes with iterative message-passing decoding. In this paper, we consider ensembles of periodically time-varying spatially coupled LDPC (SC-LDPC) codes and the pseudocodewords arising from their finite graph covers of a fixed degree. We show that for certain (J,K)-regular SC-LDPC code ensembles and a fixed cover degree, the typical minimum pseudoweight of the unterminated (and associated tail-biting/terminated) SC-LDPC code ensembles grows linearly with the Constraint (Block) length as the Constraint (Block) length tends to infinity. We prove that one can bound the the free pseudodistance growth rate over a BEC from below (respectively, above) using the associated tail-biting (terminated) SC-LDPC code ensemble and show empirically that these bounds coincide for a sufficiently large period, which gives the exact free pseudodistance growth rate for the SC-LDPC ensemble considered.

Cunlu Zhou - One of the best experts on this subject based on the ideXlab platform.

  • ITW - Free Pseudodistance Growth Rates for Spatially Coupled LDPC Codes over the BEC
    2018 IEEE Information Theory Workshop (ITW), 2018
    Co-Authors: Cunlu Zhou, David G. M. Mitchell, Roxana Smarandache
    Abstract:

    The minimum pseudoweight is an important parameter related to the decoding performance of LDPC codes with iterative message-passing decoding. In this paper, we consider ensembles of periodically time-varying spatially coupled LDPC (SC-LDPC) codes and the pseudocodewords arising from their finite graph covers of a fixed degree. We show that for certain (J,K)-regular SC-LDPC code ensembles and a fixed cover degree, the typical minimum pseudoweight of the unterminated (and associated tail-biting/terminated) SC-LDPC code ensembles grows linearly with the Constraint (Block) length as the Constraint (Block) length tends to infinity. We prove that one can bound the the free pseudodistance growth rate over a BEC from below (respectively, above) using the associated tail-biting (terminated) SC-LDPC code ensemble and show empirically that these bounds coincide for a sufficiently large period, which gives the exact free pseudodistance growth rate for the SC-LDPC ensemble considered.

  • Free Pseudodistance Growth Rates for Spatially Coupled LDPC Codes over the BEC
    2018 IEEE Information Theory Workshop (ITW), 2018
    Co-Authors: Cunlu Zhou, David G. M. Mitchell, Roxana Smarandache
    Abstract:

    The minimum pseudoweight is an important parameter related to the decoding performance of LDPC codes with iterative message-passing decoding. In this paper, we consider ensembles of periodically time-varying spatially coupled LDPC (SC-LDPC) codes and the pseudocodewords arising from their finite graph covers of a fixed degree. We show that for certain (J,K)-regular SC-LDPC code ensembles and a fixed cover degree, the typical minimum pseudoweight of the unterminated (and associated tail-biting/terminated) SC-LDPC code ensembles grows linearly with the Constraint (Block) length as the Constraint (Block) length tends to infinity. We prove that one can bound the the free pseudodistance growth rate over a BEC from below (respectively, above) using the associated tail-biting (terminated) SC-LDPC code ensemble and show empirically that these bounds coincide for a sufficiently large period, which gives the exact free pseudodistance growth rate for the SC-LDPC ensemble considered.

Shangbin Li - One of the best experts on this subject based on the ideXlab platform.

  • Human Motion Target Recognition Using Convolutional Neural Network and Global Constraint Block Matching
    IEEE Access, 2020
    Co-Authors: Shangbin Li
    Abstract:

    The traditional human behavior recognition algorithm is easy to ignore the spatial Constraint problem of feature Blocks, which leads to poor recognition effect and low correct rate. Therefore, we proposed a human motion target recognition algorithm based on Convolution Neural Network (referred to as the “CNN”) and global Constraint Block matching. First, key frames of the human motion video were extracted, second, the local feature and global feature of key frames were analyzed, and CNN was used to perform feature fusion, then, according to the result of the feature fusion, a feature Block was formed and the closest matching feature Block is obtained, using the definition of spatial Constraint, we considered the spatial data of human motion in the vertical direction, calculates the spatial Constraint weight, and further completes the matching. Finally, the score of matching Block and the spatial Constraint weight were calculated, and the human motion targets are recognized based on the cumulative score. The experimental results show that the proposed algorithm has a high key frame extraction accuracy of more than 90% and less time consumed in feature fusion, high matching accuracy of feature Blocks of more than 80%, and high feature Blocks, the F-measure of human behavior recognition is 0.95 on average, and the overall recognition performance is good.

David G. M. Mitchell - One of the best experts on this subject based on the ideXlab platform.

  • ITW - Free Pseudodistance Growth Rates for Spatially Coupled LDPC Codes over the BEC
    2018 IEEE Information Theory Workshop (ITW), 2018
    Co-Authors: Cunlu Zhou, David G. M. Mitchell, Roxana Smarandache
    Abstract:

    The minimum pseudoweight is an important parameter related to the decoding performance of LDPC codes with iterative message-passing decoding. In this paper, we consider ensembles of periodically time-varying spatially coupled LDPC (SC-LDPC) codes and the pseudocodewords arising from their finite graph covers of a fixed degree. We show that for certain (J,K)-regular SC-LDPC code ensembles and a fixed cover degree, the typical minimum pseudoweight of the unterminated (and associated tail-biting/terminated) SC-LDPC code ensembles grows linearly with the Constraint (Block) length as the Constraint (Block) length tends to infinity. We prove that one can bound the the free pseudodistance growth rate over a BEC from below (respectively, above) using the associated tail-biting (terminated) SC-LDPC code ensemble and show empirically that these bounds coincide for a sufficiently large period, which gives the exact free pseudodistance growth rate for the SC-LDPC ensemble considered.

  • Free Pseudodistance Growth Rates for Spatially Coupled LDPC Codes over the BEC
    2018 IEEE Information Theory Workshop (ITW), 2018
    Co-Authors: Cunlu Zhou, David G. M. Mitchell, Roxana Smarandache
    Abstract:

    The minimum pseudoweight is an important parameter related to the decoding performance of LDPC codes with iterative message-passing decoding. In this paper, we consider ensembles of periodically time-varying spatially coupled LDPC (SC-LDPC) codes and the pseudocodewords arising from their finite graph covers of a fixed degree. We show that for certain (J,K)-regular SC-LDPC code ensembles and a fixed cover degree, the typical minimum pseudoweight of the unterminated (and associated tail-biting/terminated) SC-LDPC code ensembles grows linearly with the Constraint (Block) length as the Constraint (Block) length tends to infinity. We prove that one can bound the the free pseudodistance growth rate over a BEC from below (respectively, above) using the associated tail-biting (terminated) SC-LDPC code ensemble and show empirically that these bounds coincide for a sufficiently large period, which gives the exact free pseudodistance growth rate for the SC-LDPC ensemble considered.

Ren N - One of the best experts on this subject based on the ideXlab platform.

  • An Accurate Authentication Algorithm Based on Point Constraint Block for Vector Geographic Data
    Journal of Geo-information Science, 2020
    Co-Authors: Ren N
    Abstract:

    Fragile watermarking technique has been viewed as an effective method to achieve content authentication, which not only detect any modifications that occurred, but also locate the modified areas. Based on fragile watermarking technology, an accurate authentication scheme based on point Constraint Block is proposed, which detects the malicious attacks with high accuracy while ensuring to locate exactly the tampered area for vector geographic data. Our innovative strategy is based on point Constraint Block and uses the spatial relationships between the elements of data points. In the authentication information embedding process, vector geographical data is divided into Blocks according to the method of point Constraint Block, and the spatial positional relationship between the data points of each Block is reordered by the "Zig-Zag" pattern, so as to establish an organized positional relationship between data points. Then, for each point, the fragile watermark information is generated by its adjacent point, and is embedded into the current point. In the process of content authentication, the extracted watermark information is compared with the generated watermark information, and the comparative result is used to judge whether the data have been updated. The proposed algorithm is furthermore compared with the method that is based on a uniform Block, and the experimental results show that the proposed authentication algorithm can accomplish accurate authentication when the data is updated, and it has the ability to achieve the accurate authentication of deleted elements. Meanwhile, when data modifications are detected, it can locate and mark the modification positions.