Reliability-Based Iterative Proportionality-logic Decoding of LDPC Codes with Adaptive Decision

Youming Sun,Haiqiang Chen,Xiangcheng Li,Lingshan Luo,Tuanfa Qin 한국통신학회 2015 Journal of communications and networks Vol.17 No.3

In this paper, we present a reliability-based iterative proportionality-logic decoding algorithm for two classes of structured low-density parity-check (LDPC) codes. The main contributions of this paper include: 1) Syndromemessages instead of extrinsic messages are processed and exchanged between variable nodes and check nodes, which can reduce the decoding complexity; 2) a more flexible decision mechanism is developed in which the decision threshold can be self-adjusted during the iterative process. Such decision mechanism is particularly effective for decoding the majority-logic decodable codes; 3) only part of the variable nodes satisfying the pre-designed criterion are involved for the presented algorithm, which is in the proportionality-logic sense and can further reduce the computational complexity. Simulation results show that, when combined with factor correction techniques and appropriate proportionality parameter, the presented algorithm performs well and can achieve fast decoding convergence rate while maintaining relative low decoding complexity, especially for small quantized levels (3–4 bits). The presented algorithm provides a candidate for those application scenarios where the memory load and the energy consumption are extremely constrained.

Iterative Reliability-Based Modified Majority-Logic Decoding for Structured Binary LDPC Codes

Haiqiang Chen,Lingshan Luo,Youming Sun,Xiangcheng Li,Haibin Wan,Liping Luo,Tuanfa Qin 한국통신학회 2015 Journal of communications and networks Vol.17 No.4

In this paper, we present an iterative reliability-based modified majority-logic decoding algorithm for two classes of structured low-density parity-check codes. Different from the conventional modified one-step majority-logic decoding algorithms, we design a turbo-like iterative strategy to recover the performance degradation caused by the simply flipping operation. The main computational loads of the presented algorithminclude only binary logic and integer operations, resulting in low decoding complexity. Furthermore, by introducing the iterative set, a very small proportion (less than 6%) of variable nodes are involved in the reliability updating process, which can further reduce the computational complexity. Simulation results show that, combined with the factor correction technique and a well-designed non-uniform quantization scheme, the presented algorithm can achieve a significant performance improvement and a fast decoding speed, even with very small quantization levels (3–4 bits resolution). The presented algorithm provides a candidate for trade-offs between performance and complexity.

Real-time prediction of wave-induced hull girder loads for a large container ship based on the recurrent neural network model and error correction strategy

Wang Qiang,Yu Pengyao,Lv Mingdong,Wu Xiangcheng,Li Chenfeng,Chang Xin,Wu Lihong 대한조선학회 2024 International Journal of Naval Architecture and Oc Vol.16 No.-

Real-time acquisition of wave-induced hull girder loads of a sailing ship will help the captain make reasonable decisions, which is of great significance for improving the safety of the ship’s navigation. This paper investigates the real-time prediction method of hull girder loads based on the Recurrent Neural Network (RNN) model and error correction strategy. Firstly, taking the vertical bending moment, horizontal bending moment, and torsional moment at the mid-ship position of a large container ship as examples, corresponding neural network prediction models are established through parameter influence analysis. Secondly, various sea state conditions are used to verify the feasibility of established network prediction models to predict the hull girder loads in real-time. The VBM prediction model performs better than the TM prediction model and HBM prediction model, and the errors of the TM prediction model and HBM prediction model are slightly larger in some cases. Lastly, an improved prediction model based on an error correction strategy is proposed to improve the prediction accuracy of the neural network prediction model, and the adequate performance of the error correction strategy is discussed.

Novel Nucleotide Variations, Haplotypes Structure and Associations with Growth Related Traits of Goat AT Motif-Binding Factor (ATBF1) Gene

Zhang, Xiaoyan,Wu, Xianfeng,Jia, Wenchao,Pan, Chuanying,Li, Xiangcheng,Lei, Chuzhao,Chen, Hong,Lan, Xianyong Asian Australasian Association of Animal Productio 2015 Animal Bioscience Vol.28 No.10

The AT motif-binding factor (ATBF1) not only interacts with protein inhibitor of activated signal transducer and activator of transcription 3 (STAT3) (PIAS3) to suppress STAT3 signaling regulating embryo early development and cell differentiation, but is required for early activation of the pituitary specific transcription factor 1 (Pit1) gene (also known as POU1F1) critically affecting mammalian growth and development. The goal of this study was to detect novel nucleotide variations and haplotypes structure of the ATBF1 gene, as well as to test their associations with growth-related traits in goats. Herein, a total of seven novel single nucleotide polymorphisms (SNPs) (SNP 1-7) within this gene were found in two well-known Chinese native goat breeds. Haplotypes structure analysis demonstrated that there were four haplotypes in Hainan black goat while seventeen haplotypes in Xinong Saanen dairy goat, and both breeds only shared one haplotype (hap1). Association testing revealed that the SNP2, SNP5, SNP6, and SNP7 loci were also found to significantly associate with growth-related traits in goats, respectively. Moreover, one diplotype in Xinong Saanen dairy goats significantly linked to growth related traits. These preliminary findings not only would extend the spectrum of genetic variations of the goat ATBF1 gene, but also would contribute to implementing marker-assisted selection in genetics and breeding in goats.

Novel Nucleotide Variations, Haplotypes Structure and Associations with Growth Related Traits of Goat AT Motif-Binding Factor (ATBF1) Gene

Xiaoyan Zhang,Xianfeng Wu,Wenchao Jia,Chuanying Pan,Xiangcheng Li,Chuzhao Lei,Hong Chen,Xianyong Lan 아세아·태평양축산학회 2015 Animal Bioscience Vol.28 No.10

The AT motif-binding factor (ATBF1) not only interacts with protein inhibitor of activated signal transducer and activator of transcription 3 (STAT3) (PIAS3) to suppress STAT3 signaling regulating embryo early development and cell differentiation, but is required for early activation of the pituitary specific transcription factor 1 (Pit1) gene (also known as POU1F1) critically affecting mammalian growth and development. The goal of this study was to detect novel nucleotide variations and haplotypes structure of the ATBF1 gene, as well as to test their associations with growth-related traits in goats. Herein, a total of seven novel single nucleotide polymorphisms (SNPs) (SNP 1-7) within this gene were found in two well-known Chinese native goat breeds. Haplotypes structure analysis demonstrated that there were four haplotypes in Hainan black goat while seventeen haplotypes in Xinong Saanen dairy goat, and both breeds only shared one haplotype (hap1). Association testing revealed that the SNP2, SNP5, SNP6, and SNP7 loci were also found to significantly associate with growth-related traits in goats, respectively. Moreover, one diplotype in Xinong Saanen dairy goats significantly linked to growth related traits. These preliminary findings not only would extend the spectrum of genetic variations of the goat ATBF1 gene, but also would contribute to implementing marker-assisted selection in genetics and breeding in goats.

Discovery of the leinamycin family of natural products by mining actinobacterial genomes

Pan, Guohui,Xu, Zhengren,Guo, Zhikai,Hindra,Ma, Ming,Yang, Dong,Zhou, Hao,Gansemans, Yannick,Zhu, Xiangcheng,Huang, Yong,Zhao, Li-Xing,Jiang, Yi,Cheng, Jinhua,Van Nieuwerburgh, Filip,Suh, Joo-Won,Duan National Academy of Sciences 2017 PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF Vol.114 No.52

<P>Nature's ability to generate diverse natural products from simple building blocks has inspired combinatorial biosynthesis. The knowledge-based approach to combinatorial biosynthesis has allowed the production of designer analogs by rational metabolic pathway engineering. While successful, structural alterations are limited, with designer analogs often produced in compromised titers. The discovery-based approach to combinatorial biosynthesis complements the knowledge-based approach by exploring the vast combinatorial biosynthesis repertoire found in Nature. Here we showcase the discovery-based approach to combinatorial biosynthesis by targeting the domain of unknown function and cysteine lyase domain (DUF-SH) didomain, specific for sulfur incorporation from the leinamycin (LNM) biosynthetic machinery, to discover the LNM family of natural products. By mining bacterial genomes from public databases and the actinomycetes strain collection at The Scripps Research Institute, we discovered 49 potential producers that could be grouped into 18 distinct clades based on phylogenetic analysis of the DUF-SH didomains. Further analysis of the representative genomes from each of the clades identified 28 lnm-type gene clusters. Structural diversities encoded by the LNM-type biosynthetic machineries were predicted based on bioinformatics and confirmed by in vitro characterization of selected adenylation proteins and isolation and structural elucidation of the guangnanmycins and weishanmycins. These findings demonstrate the power of the discovery-based approach to combinatorial biosynthesis for natural product discovery and structural diversity and highlight Nature's rich biosynthetic repertoire. Comparative analysis of the LNM-type biosynthetic machineries provides outstanding opportunities to dissect Nature's biosynthetic strategies and apply these findings to combinatorial biosynthesis for natural product discovery and structural diversity.</P>

Fabrication accuracy analysis of micromilling tools with complicated geometries by wire EDM

Xiang Cheng,Xianhai Yang,Guangming Zheng,Yumei Huang,Li Li 대한기계학회 2014 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.28 No.6

The micromilling tool is one of the key factors affecting micromilling performance. The design and fabrication of micromilling toolsare still behind the increasing requirements in miniature component fabrication. How to estimate the fabrication accuracy of a newlydesigned micromilling tool is one of the urgent issues for micro tooling. This paper introduces an accuracy analysis method in the fabricationof micromilling tools by wire electrical discharge machining (WEDM) process. Taking two typical micro ball end mills into consideration,the micro tool fabrication process is kinematically modeled and analyzed. Analytical results show that the final fabricationaccuracy has a close relationship with the designed micro tool geometry. The fabrication procedures can be arranged based on the kinematicalanalysis, and the final fabrication accuracy also is affected by it. The radius errors of the fabricated micro ball end mill prototypeare within ±2μm, which is higher than that of commercially available similar ones. It verifies the proposed accuracy analysis method.

Translationally controlled tumor protein (TCTP) downregulates Oct4 expression in mouse pluripotent cells

( Xiang Cheng ),( Jun Hua Li ),( Jie Deng ),( Zhen Zhen Li ),( Shu Yan Meng ),( Hua Yan Wang ) 생화학분자생물학회 (구 한국생화학분자생물학회) 2012 BMB Reports Vol.45 No.1

The present study aimed to investigate the function of translationally controlled tumor protein (TCTP) in the regulation of Oct4 in mouse embryonic carcinoma P19 cells and mouse J1 embryonic stem (ES) cells. The mRNA level of endogenous TCTP in somatic cells was 2-4 folds higher than that in pluripotent P19 and J1 ES cells. Overexpression of TCTP in mouse pluripotent cells not only reduced the level of Oct4 transcription, but also decreased the pluripotency of stem cells. The N-terminal end of TCTP (amino acids 1-60) played an important role in suppressing the Oct4 promoter. Moreover, overexpression of TCTP in P19 cells suppressed the Oct4 promoter activity in a dose- and a time-dependent manner. In addition, knockdown of TCTP by small interfering RNA increased the expression of Oct4. Our study indicates that TCTP downregulates the Oct4 expression by binding the Sf1 site of Oct4 promoter in mouse pluripotent cells. [BMB reports 2012; 45(1): 20-25]