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The Self-dual Codes over Formal Power Series Rings 被引量:1
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作者 LIU Xiu-sheng LIU Hua-lu 《Chinese Quarterly Journal of Mathematics》 CSCD 2014年第1期30-38,共9页
The codes of formal power series rings R_∞=F[[r]]={sum from i=0 to ∞(a_lr^l|a_l∈F)}and finite chain rings R_i={a_0+a_1r+…+a_(i-1)r^(i-1)|a_i∈F}have close relationship in lifts and projection.In this paper,we stud... The codes of formal power series rings R_∞=F[[r]]={sum from i=0 to ∞(a_lr^l|a_l∈F)}and finite chain rings R_i={a_0+a_1r+…+a_(i-1)r^(i-1)|a_i∈F}have close relationship in lifts and projection.In this paper,we study self-dual codes over R_∞by means of self-dual codes over Ri,and give some characterizations of self-dual codes over R_∞. 展开更多
关键词 self-dual codes γ-adic codes projective codes
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Self-dual Codes with Symplectic Inner Product
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作者 Nan Ji-zhu Yu Xue-min Du Xian-kun 《Communications in Mathematical Research》 CSCD 2015年第4期345-350,共6页
In this paper, we discuss a kind of Hermitian inner product - symplectic inner product, which is different from the original inner product - Euclidean inner product. According to the definition of symplectic inner pro... In this paper, we discuss a kind of Hermitian inner product - symplectic inner product, which is different from the original inner product - Euclidean inner product. According to the definition of symplectic inner product, the codes under the symplectic inner product have better properties than those under the general Hermitian inner product. Here we present the necessary and sufficient condition for judging whether a linear code C over Fp with a generator matrix in the standard form is a symplectic self-dual code. In addition, we give a method for constructing a new symplectic self-dual codes over Fp, which is simpler than others. 展开更多
关键词 symplectic inner product symplectic self-dual code symplectic circu- lant code
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Self-dual Codes Defined on Factor Graphs
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作者 汪辉松 汪隽 +1 位作者 杜群 曾贵华 《Journal of Shanghai Jiaotong university(Science)》 EI 2007年第4期433-436,共4页
A definition of a self-dual code on graph and a procedure based on factor graphs to judge a self-dual code were presented. Three contributions of this paper were described as follows. To begin with, transform T_ R→L ... A definition of a self-dual code on graph and a procedure based on factor graphs to judge a self-dual code were presented. Three contributions of this paper were described as follows. To begin with, transform T_ R→L were defined, which was the basis of self-dual codes defined on graphs and played a key role in the paper. The second were that a self-dual code could be defined on factor graph, which was much different from conventional algebraic method. The third was that a factor graph approach to judge a self-dual code was illustrated, which took advantage of duality properties of factor graphs and our proposed transform T_ R→L to offer a convenient and geometrically intuitive process to judge a self-dual code. 展开更多
关键词 FACTOR GRAPH self-dual code DUAL PROPERTY error-correcting code
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Construction of Self-dual Codes over F_p+vF_p
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作者 ZHANG Guang-hui WANG Dong-qing 《Chinese Quarterly Journal of Mathematics》 2018年第4期358-368,共11页
In this paper, we give an explicit construction for self-dual codes over F_p+vF_p(v^2= v) and determine all the self-dual codes over F_p+ vF_p by using self-dual codes over finite field F_p, where p is a prime.
关键词 Linear code self-dual code codes OVER Fp +vFp non-chain ring
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New MDS Euclidean and Hermitian Self-Dual Codes over Finite Fields
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作者 Hongxi Tong Xiaoqing Wang 《Advances in Pure Mathematics》 2017年第5期325-333,共9页
In this paper, we construct MDS Euclidean self-dual codes which are ex-tended cyclic duadic codes. And we obtain many new MDS Euclidean self-dual codes. We also construct MDS Hermitian self-dual codes from generalized... In this paper, we construct MDS Euclidean self-dual codes which are ex-tended cyclic duadic codes. And we obtain many new MDS Euclidean self-dual codes. We also construct MDS Hermitian self-dual codes from generalized Reed-Solomon codes and constacyclic codes. 展开更多
关键词 MDS Euclidean self-dual codes MDS HERMITIAN self-dual codes Constacyclic codes CYCLIC Duadic codes Generalized REED-SOLOMON codes
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Rateless Polar Codes with Unequal Error Protection Property
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作者 Cui Chen Xiang Wei +1 位作者 Ma Siwei Guo Qing 《China Communications》 2026年第1期10-23,共14页
Mobile communications are reaching out to every aspect of our daily life,necessitating highefficiency data transmission and support for diverse data types and communication scenarios.Polar codes have emerged as a prom... Mobile communications are reaching out to every aspect of our daily life,necessitating highefficiency data transmission and support for diverse data types and communication scenarios.Polar codes have emerged as a promising solution due to their outstanding error-correction performance and low complexity.Unequal error protection(UEP)involves nonuniform error safeguarding for distinct data segments,achieving a fine balance between error resilience and resource allocation,which ultimately enhancing system performance and efficiency.In this paper,we propose a novel class of UEP rateless polar codes.The codes are designed based on matrix extension of polar codes,and elegant mapping and duplication operations are designed to achieve UEP property while preserving the overall performance of conventional polar codes.Superior UEP performance is attained without significant modifications to conventional polar codes,making it straightforward for compatibility with existing polar codes.A theoretical analysis is conducted on the block error rate and throughput efficiency performance.To the best of our knowledge,this work provides the first theoretical performance analysis of UEP rateless polar codes.Simulation results show that the proposed codes significantly outperform existing polar coding schemes in both block error rate and throughput efficiency. 展开更多
关键词 matrix extension polar codes rateless coding unequal error protection
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Efficient Polar Codes with Low Complexity for Correcting Insertions/Deletions in DPPM
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作者 Li Leran Liu Yuan +2 位作者 Yuan Ye Xiahou Wenqian Chen Maonan 《China Communications》 2026年第1期24-33,共10页
Differential pulse-position modulation(DP PM)can achieve a good compromise between power and bandwidth requirements.However,the output sequence has undetectable insertions and deletions.This paper proposes a successiv... Differential pulse-position modulation(DP PM)can achieve a good compromise between power and bandwidth requirements.However,the output sequence has undetectable insertions and deletions.This paper proposes a successive cancellation(SC)decoding scheme based on the weighted levenshtein distance(WLD)of polar codes for correcting insertions/deletions in DPPM systems.In this method,the WLD is used to calculate the transfer probabilities recursively to obtain likelihood ratios,and the low-complexity SC decoding method is built according to the error characteristics to match the DPPM system.Additionally,the proposed SC decoding scheme is extended to list decoding,which can further improve error correction performance.Simulation results show that the proposed scheme can effectively correct insertions/deletions in the DPPM system,which enhances its reliability and performance. 展开更多
关键词 DPPM insertions/deletions polar codes SC decoding
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TLS Blind Recognition Algorithm of LDPC Codes
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作者 Ning Xiaoyan Sun Jingjing +1 位作者 Wang Zhenduo Sun Zhiguo 《China Communications》 2026年第2期112-121,共10页
Blind recognition of low-density paritycheck(LDPC)codes has gradually attracted more attention with the development of military and civil communications.However,in the case of the paritycheck matrices with relatively ... Blind recognition of low-density paritycheck(LDPC)codes has gradually attracted more attention with the development of military and civil communications.However,in the case of the paritycheck matrices with relatively high row weights,the existing blind recognition algorithms based on a candidate set generally perform worse.In this paper,we propose a blind recognition method for LDPC codes,called as tangent function assisted least square(TLS)method,which improves recognition performances by constructing a new cost function.To characterize the constraint degree among received vectors and paritycheck vectors,a feature function based on tangent function is constructed in the proposed algorithm.A cost function based on least square method is also established according to the feature function values satisfying the parity-check relationship.Moreover,the minimum average value in TLS is obtained on the candidate set.Numerical analysis and simulation results show that recognition performances of TLS algorithm are consistent with theoretical results.Compared with existing algorithms,the proposed method possesses better recognition performances. 展开更多
关键词 blind recognition cost function least square low-density parity-check(LDPC)codes
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SELF-DUAL PERMUTATION CODES OVER FORMAL POWER SERIES RINGS AND FINITE PRINCIPAL IDEAL RINGS 被引量:1
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作者 张光辉 刘宏伟 《Acta Mathematica Scientia》 SCIE CSCD 2013年第6期1695-1710,共16页
In this paper, we study self-dual permutation codes over formal power series rings and finite principal ideal rings. We first give some results on the torsion codes associated with the linear codes over formal power s... In this paper, we study self-dual permutation codes over formal power series rings and finite principal ideal rings. We first give some results on the torsion codes associated with the linear codes over formal power series rings. These results allow for obtaining some conditions for non-existence of self-dual permutation codes over formal power series rings. Finally, we describe self-dual permutation codes over finite principal ideal rings by examining permutation codes over their component chain rings. 展开更多
关键词 self-dual code group code permutation code formal power series ring finiteprincipal ideal ring
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Self-Dual Permutation Codes over Finite Chain Rings 被引量:1
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作者 YUAN Yuan ZHANG Huanguo 《Wuhan University Journal of Natural Sciences》 CAS 2007年第6期992-996,共5页
Permutation codes over finite chain rings are introduced; by using the character of the finite chain rings and the knowledge of representation of group, some conditions for existence or non-existence of self-dual perm... Permutation codes over finite chain rings are introduced; by using the character of the finite chain rings and the knowledge of representation of group, some conditions for existence or non-existence of self-dual permutation codes over finite chain rings are obtained. Specially, when the group is a direct product of a 2-group and a T-group, and the group action is transitive, the sufficient and necessary condition of the existence of permutation codes is given. 展开更多
关键词 finite chain ring group code permutation code self-dual code
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ON SELF-DUAL PERMUTATION CODES
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作者 樊恽 袁媛 《Acta Mathematica Scientia》 SCIE CSCD 2008年第3期633-638,共6页
Permutation codes over finite fields are introduced, some conditions for existence or non-existence of self-dual permutation codes are obtained.
关键词 Finite field group code permutation code self-dual code
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Pliable Fraction Repetition Codes for Access-balancing in Distributed Storage
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作者 LI Yueting 《数学进展》 北大核心 2025年第1期73-84,共12页
Fraction repetition(FR)codes are integral in distributed storage systems(DSS)with exact repair-by-transfer,while pliable fraction repetition codes are vital for DSSs in which both the per-node storage and repetition d... Fraction repetition(FR)codes are integral in distributed storage systems(DSS)with exact repair-by-transfer,while pliable fraction repetition codes are vital for DSSs in which both the per-node storage and repetition degree can easily be adjusted simultaneously.This paper introduces a new type of pliable FR codes,called absolute balanced pliable FR(ABPFR)codes,in which the access balancing in DSS is considered.Additionally,the equivalence between pliable FR codes and resolvable transversal packings in combinatorial design theory is presented.Then constructions of pliable FR codes and ABPFR codes based on resolvable transversal packings are presented. 展开更多
关键词 distributed storage system pliable fraction repetition code access balancing resolvable transversal packing
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Construction of Constant Rank and Orbit Codes over Finite Chain Rings
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作者 GUO Ye LIU Xiusheng 《Wuhan University Journal of Natural Sciences》 2025年第3期289-301,共13页
In this paper,we first generalize the constant dimension and orbit codes over finite fields to the constant rank and orbit codes over finite chain rings.Then we provide a relationship between constant rank codes over ... In this paper,we first generalize the constant dimension and orbit codes over finite fields to the constant rank and orbit codes over finite chain rings.Then we provide a relationship between constant rank codes over finite chain rings and constant dimension codes over the residue fields.In particular,we prove that an orbit submodule code over a finite chain ring is a constant rank code.Finally,for special finite chain ring F_(q)+γF_(q),we define a Gray mapφfrom(F_(q)+γF_(q))^(n)to F^(2n)_(q),and by using cyclic codes over F_(q)+γF_(q),we obtain a method of constructing an optimum distance constant dimension code over F_(q). 展开更多
关键词 finite chain ring rank of linear codes constant rank codes orbit codes
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Neural Codes Constructs Based on Combinatorial Design
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作者 Jin Huang 《Applied Mathematics》 2025年第1期42-60,共19页
Neuroscience (also known as neurobiology) is a science that studies the structure, function, development, pharmacology and pathology of the nervous system. In recent years, C. Cotardo has introduced coding theory into... Neuroscience (also known as neurobiology) is a science that studies the structure, function, development, pharmacology and pathology of the nervous system. In recent years, C. Cotardo has introduced coding theory into neuroscience, proposing the concept of combinatorial neural codes. And it was further studied in depth using algebraic methods by C. Curto. In this paper, we construct a class of combinatorial neural codes with special properties based on classical combinatorial structures such as orthogonal Latin rectangle, disjoint Steiner systems, groupable designs and transversal designs. These neural codes have significant weight distribution properties and large minimum distances, and are thus valuable for potential applications in information representation and neuroscience. This study provides new ideas for the construction method and property analysis of combinatorial neural codes, and enriches the study of algebraic coding theory. 展开更多
关键词 Combinatorial Neural codes Orthogonal Latin Rectangle Steiner System Group Divisible Design Transversal Design
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Shortened PAC Codes and List Decoding
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作者 LIU Aolin FENG Bowen +2 位作者 LIANG Chulong XU Jin ZHANG Qinyu 《ZTE Communications》 2025年第4期86-96,共11页
Shortening is a standard rate-matching method for polar codes in wireless communications.Since polarization-adjusted convolu⁃tional(PAC)codes also have a block length limited to the integer powers of two,they also req... Shortening is a standard rate-matching method for polar codes in wireless communications.Since polarization-adjusted convolu⁃tional(PAC)codes also have a block length limited to the integer powers of two,they also require rate-matching.To this end,we first analyze the limitations of existing shortening patterns for PAC codes and explore their feasibility.Subsequently,we propose a novel shortening scheme for PAC codes based on list decoding,where the receiver is allowed to treat the values of the deleted bits as undetermined.This ap⁃proach uses a specialized PAC codeword and activates multiple decoding paths during the initialization of list decoding,enabling it to achieve the desired reliability. 展开更多
关键词 polarization-adjusted convolutional codes rate-matching shortened codes list decoding
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Research on deep learning decoding method for polar codes in ACO-OFDM spatial optical communication system
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作者 LIU Kangrui LI Ming +2 位作者 CHEN Sizhe QU Jiashun ZHOU Ming’ou 《Optoelectronics Letters》 2025年第7期427-433,共7页
Aiming at the problem that the bit error rate(BER)of asymmetrically clipped optical orthogonal frequency division multiplexing(ACO-OFDM)space optical communication system is significantly affected by different turbule... Aiming at the problem that the bit error rate(BER)of asymmetrically clipped optical orthogonal frequency division multiplexing(ACO-OFDM)space optical communication system is significantly affected by different turbulence intensities,the deep learning technique is proposed to the polarization code decoding in ACO-OFDM space optical communication system.Moreover,this system realizes the polarization code decoding and signal demodulation without frequency conduction with superior performance and robustness compared with the performance of traditional decoder.Simulations under different turbulence intensities as well as different mapping orders show that the convolutional neural network(CNN)decoder trained under weak-medium-strong turbulence atmospheric channels achieves a performance improvement of about 10^(2)compared to the conventional decoder at 4-quadrature amplitude modulation(4QAM),and the BERs for both 16QAM and 64QAM are in between those of the conventional decoder. 展开更多
关键词 frequency conduction polar codes deep learning signal demodulation deep learning technique DECODING ACO OFDM polarization code decoding
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ASME Code Case 3029高温许用压应力计算方法的介绍及工程应用
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作者 马忠明 《化工设备与管道》 北大核心 2026年第1期24-30,共7页
介绍了高温蠕变工况下运行的压力容器可能出现的失效模式,结合工程设计现状,指出了我国当前压力容器标准体系在确定高温蠕变工况许用压应力时存在的技术瓶颈,在此基础之上引出ASME Code Case 3029,对其适用范围、发展历程、产生背景及... 介绍了高温蠕变工况下运行的压力容器可能出现的失效模式,结合工程设计现状,指出了我国当前压力容器标准体系在确定高温蠕变工况许用压应力时存在的技术瓶颈,在此基础之上引出ASME Code Case 3029,对其适用范围、发展历程、产生背景及工程意义进行了简单的介绍,以某工程设计项目中的实际结构为例,介绍了该方法的使用过程及注意事项,并结合压力容器工程设计领域的实际需求,对我国标准体系下一步的制定或修订方向提出了展望。 展开更多
关键词 code Case 3029 蠕变屈曲 失稳 压力容器 许用应力
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ChatGPT+VS Code在高中地理地图开发中的应用——以“国内人口迁移”为例
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作者 王凌宇 白絮飞 《中国信息技术教育》 2026年第1期81-84,共4页
人工智能技术在中学地理教学中的应用是大势所趋。当前的研究主要聚焦于其作为学生的“助学者”和教师的“助教者”两大角色。然而,现有应用方式存在一定局限性:作为“助学者”,若学生使用不当可能引发依赖性,削弱其独立思考能力;作为... 人工智能技术在中学地理教学中的应用是大势所趋。当前的研究主要聚焦于其作为学生的“助学者”和教师的“助教者”两大角色。然而,现有应用方式存在一定局限性:作为“助学者”,若学生使用不当可能引发依赖性,削弱其独立思考能力;作为“助教者”,若教师生成教学设计的指令过于宽泛,结果易出现“张冠李戴”或“似是而非”等问题,需教师二次加工。相反,若教师能针对教学设计中的特定模块提供详细准确的指令,人工智能技术输出的结果将更具准确性和实用性,展现出更高研究价值。因此,本文从人工智能技术“助教者”身份出发,摒弃传统完整的教学过程设计,聚焦备课中的“地图开发”模块,采用由人工智能技术生成地图代码并通过第三方软件运行的方式,实现快速辅助教师生成所需地图的目标,提升备课效率与教学质量。 展开更多
关键词 ChatGPT VS code 人工智能技术 中学地理 地图开发
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Lightweight Deep Learning Model and Novel Dataset for Restoring Damaged Barcodes and QR Codes in Logistics Applications
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作者 Tarek Muallim Haluk Kucuk +1 位作者 Muhammet Bareket Metin Kahraman 《Computer Modeling in Engineering & Sciences》 2025年第6期3557-3581,共25页
This study introduces a lightweight deep learning model and a novel synthetic dataset designed to restore damaged one-dimensional(1D)barcodes and Quick Response(QR)codes,addressing critical challenges in logistics ope... This study introduces a lightweight deep learning model and a novel synthetic dataset designed to restore damaged one-dimensional(1D)barcodes and Quick Response(QR)codes,addressing critical challenges in logistics operations.The proposed solution leverages an efficient Pix2Pix-based framework,a type of conditional Generative Adversarial Network(GAN)optimized for image-to-image translation tasks,enabling the recovery of degraded barcodes and QR codes with minimal computational overhead.A core contribution of this work is the development of a synthetic dataset that simulates realistic damage scenarios frequently encountered in logistics environments,such as low contrast,misalignment,physical wear,and environmental interference.By training on this diverse and realistic dataset,the model demonstrates exceptional performance in restoring readability and decoding accuracy.The lightweight architecture,featuring a U-Net-based encoder-decoder with separable convolutions,ensures computational efficiency,making the approach suitable for real-time deployment on embedded and resource-constrained devices commonly used in logistics systems.Experimental results reveal significant improvements:QR code decoding ratios increased from 14%to 99%on training data and from 15%to 68%on validation data,while 1D barcode decoding ratios improved from 7%to 73%on training data and from 9%to 44%on validation data.By providing a robust,resource-efficient solution for restoring damaged barcodes and QR codes,this study offers practical advancements for enhancing the reliability of automated scanning systems in logistics operations,particularly under challenging conditions. 展开更多
关键词 BARcode quick response code RESTORATION applied deep learning
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Minimal Binary Codes over a Ring
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作者 PAN Yang GUO Yuxin YE Chang 《湖州师范学院学报》 2025年第2期1-7,共7页
We construct an infinite family of minimal linear codes over the ring F_(2)+u F_(2).These codes are defined through trace functions and Boolean functions.Their Lee weight distribution is completely computed by Walsh t... We construct an infinite family of minimal linear codes over the ring F_(2)+u F_(2).These codes are defined through trace functions and Boolean functions.Their Lee weight distribution is completely computed by Walsh transformation.By Gray mapping,we obtain a family of minimal binary linear codes from a generic construction,which have prominent applications in secret sharing and secure two-party computation. 展开更多
关键词 Boolean function trace function minimal code secret sharing
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