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Research of Methods for Lost Data Reconstruction in Erasure Codes over Binary Fields 被引量:2
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作者 Dan Tang 《Journal of Electronic Science and Technology》 CAS CSCD 2016年第1期43-48,共6页
In the process of encoding and decoding,erasure codes over binary fields,which just need AND operations and XOR operations and therefore have a high computational efficiency,are widely used in various fields of inform... In the process of encoding and decoding,erasure codes over binary fields,which just need AND operations and XOR operations and therefore have a high computational efficiency,are widely used in various fields of information technology.A matrix decoding method is proposed in this paper.The method is a universal data reconstruction scheme for erasure codes over binary fields.Besides a pre-judgment that whether errors can be recovered,the method can rebuild sectors of loss data on a fault-tolerant storage system constructed by erasure codes for disk errors.Data reconstruction process of the new method has simple and clear steps,so it is beneficial for implementation of computer codes.And more,it can be applied to other non-binary fields easily,so it is expected that the method has an extensive application in the future. 展开更多
关键词 Binary fields data reconstruction decoding erasure codes
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Using Normal Form of Nilpotent Matrices over Finite Fields to Construct Cartesian Authentication Codes 被引量:5
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作者 赵辉芳 秦德生 《Northeastern Mathematical Journal》 CSCD 2004年第4期415-423,共9页
Let Fq be a finite field. In this paper, a construction of Cartesian au-thentication codes from the normal form of a class of nilpotent matrices over the field Fq is presented. Moreover, assume that the encoding rules... Let Fq be a finite field. In this paper, a construction of Cartesian au-thentication codes from the normal form of a class of nilpotent matrices over the field Fq is presented. Moreover, assume that the encoding rules are chosen according to a uniform probability distribution, the probabilities PI and PS, of a successful im-personation attack and of a successful substitution attack respectively, of these codes are also computed. 展开更多
关键词 cartesian authentication codes finite field nilpotent matrices
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Complex field network-coded cooperation based on multi-user detection in wireless networks 被引量:2
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作者 Jing Wang Xiangyang Liu +1 位作者 Kaikai Chi Xiangmo Zhao 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2013年第2期215-221,共7页
Cooperative communication can achieve spatial diversity gains,and consequently combats signal fading due to multipath propagation in wireless networks powerfully.A novel complex field network-coded cooperation(CFNCC... Cooperative communication can achieve spatial diversity gains,and consequently combats signal fading due to multipath propagation in wireless networks powerfully.A novel complex field network-coded cooperation(CFNCC) scheme based on multi-user detection for the multiple unicast transmission is proposed.Theoretic analysis and simulation results demonstrate that,compared with the conventional cooperation(CC) scheme and network-coded cooperation(NCC) scheme,CFNCC would obtain higher network throughput and consumes less time slots.Moreover,a further investigation is made for the symbol error probability(SEP) performance of CFNCC scheme,and SEPs of CFNCC scheme are compared with those of NCC scheme in various scenarios for different signal to noise ratio(SNR) values. 展开更多
关键词 network coding complex field wireless network cooperative communication multi-user detection
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A Construction of Multi-Sender Authentication Codes from Eigenvalues and Eigenvectors of the Matrix Over Finite Fields
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作者 Xiuli Wang Lina Wang Yakun Hao 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2019年第1期51-60,共10页
We construct one multi-sender authentication code by algebraic combination method from eigenvalues and eigenvectors of the matrix over nite elds. Some parameters and the probabilities of three kinds of successful atta... We construct one multi-sender authentication code by algebraic combination method from eigenvalues and eigenvectors of the matrix over nite elds. Some parameters and the probabilities of three kinds of successful attack of this code are also computed. For multi-sender authentication code,it allows a group of senders to construct an authenticated message for a receiver such that the receiver can verify authenticity of the received message. 展开更多
关键词 multi-sender AUTHENTICATION codes NONSINGULAR symmetric matrix EIGENVALUES EIGENVECTORS finite fields
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基于电子调控的可重构声学编码超表面
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作者 梅子恒 李澔翔 +2 位作者 莫添立 刘砚一 胡洁 《物理学报》 北大核心 2026年第7期464-473,共10页
本文提出一种基于压电复合结构单元的主动可调谐超薄声学编码超表面,单元采用压电复合片(PZT-5H)耦合双亥姆霍兹谐振腔设计,通过简单切换外接电路的开/短路状态,即可主动、瞬时地控制单元在“0”/“1”两种编码态之间转换,基于此实现超... 本文提出一种基于压电复合结构单元的主动可调谐超薄声学编码超表面,单元采用压电复合片(PZT-5H)耦合双亥姆霍兹谐振腔设计,通过简单切换外接电路的开/短路状态,即可主动、瞬时地控制单元在“0”/“1”两种编码态之间转换,基于此实现超薄声超表面的多功能动态重构.通过灵活设计相位编码序列,成功构建可精准操控波束偏转的分束型超表面(单束、二分束、四分束)、可实现任意焦点声能汇聚的声学菲涅耳透镜,以及可灵活生成并调控的高质量声学涡旋束.该设计以电子调控突破传统声学超表面瓶颈,为主动可调声场操控(如声学隐身、定向传声及粒子操控)提供了新思路. 展开更多
关键词 压电复合结构 主动调控 编码超表面 声场操控
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基于二维码技术的土木工程认知实践码课教学研究
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作者 粟滨 张向京 +3 位作者 阮波 国巍 易亮 王卫东 《实验科学与技术》 2026年第2期94-99,共6页
二维码技术已深入到生活学习中的方方面面,并深受学生喜爱。为激发大学生学习兴趣,培养自主探索、工程实践能力,丰富对实际工程的多层次感知,该文将二维码技术应用于土木工程认知实践教学,介绍了土木工程认知实践二维码设计思路、制作... 二维码技术已深入到生活学习中的方方面面,并深受学生喜爱。为激发大学生学习兴趣,培养自主探索、工程实践能力,丰富对实际工程的多层次感知,该文将二维码技术应用于土木工程认知实践教学,介绍了土木工程认知实践二维码设计思路、制作方法、应用步骤、未来展望以及应用效果。依托二维码技术,形成将多媒体资源与小比例静态模型相结合的新模式,弥补了传统土木工程认知实践教学中实地参访模式安全风险高、成本投入高、实践内容局限等不足,提升了学生学习自主性,强化了师生互动交流,可为高校实践教学模式改革提供借鉴。 展开更多
关键词 土木工程 二维码技术 码课 教学模型 实习实践
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缝纫机械领域的专利跨领域检索策略分析
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作者 彭双 《上海纺织科技》 2026年第4期64-66,共3页
针对缝纫机械领域跨领域专利案件存在的领域跨度大、分类号分散等难点,首先剖析了缝纫机械跨领域案件的技术特点与检索痛点,进而系统介绍了3种具有针对性的检索策略。结合具体实际案例,详细演示了这些策略在检索工作中的具体应用,分析... 针对缝纫机械领域跨领域专利案件存在的领域跨度大、分类号分散等难点,首先剖析了缝纫机械跨领域案件的技术特点与检索痛点,进而系统介绍了3种具有针对性的检索策略。结合具体实际案例,详细演示了这些策略在检索工作中的具体应用,分析了其应对不同难题时的操作逻辑。提出的检索策略为缝纫机械领域跨领域案件检索提供了可行方案,具有一定指导意义。 展开更多
关键词 专利 缝纫机械 检索策略 专利分类号 跨领域
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基于置换多项式簇的五类置换码构造及其参数分析
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作者 叶娜 夏永波 《数学杂志》 2026年第1期20-30,共11页
本文研究了基于有限域上的置换多项式构造置换码的问题.利用有限域上形如f(x)=αx^(m)+βx(其中m为正整数)的置换多项式簇,构造了五类置换码,并借助求解有限域上代数方程的一些方法,确定了这五类置换码的参数,包括码长、码字数量和极小... 本文研究了基于有限域上的置换多项式构造置换码的问题.利用有限域上形如f(x)=αx^(m)+βx(其中m为正整数)的置换多项式簇,构造了五类置换码,并借助求解有限域上代数方程的一些方法,确定了这五类置换码的参数,包括码长、码字数量和极小汉明距离,所得结果丰富了置换码的构造理论. 展开更多
关键词 置换多项式 置换码 极小汉明距离 码字数量 有限域
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网络环境下基于Erasure Codes的高可靠性存储体系设计 被引量:1
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作者 贾军博 谷建华 +1 位作者 朱靖飞 张集文 《计算机应用研究》 CSCD 北大核心 2009年第5期1835-1838,共4页
设计了一种基于Erasure Codes的网络环境下的分布式文件存储系统。初步的实验结果证明这种存储体系可以较好地解决人们当前所面临的文件存储的可靠性、安全性等问题。
关键词 分布式存储 数据可靠性 数据安全性 纠错码 加罗华域
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基于FPGA可变码元速率的MSK正交调制实现
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作者 尼之靖 刘世刚 +2 位作者 汪洋 齐孟鑫 魏苗苗 《电子产品可靠性与环境试验》 2026年第1期80-87,共8页
在现代通信中,高效可靠的调制算法可有效提升信号传输质量,进而改善通信系统整体性能。基于正交调制原理,设计并实现了一种码元速率可变的最小频移键控(MSK)正交调制方法。该方法在Xilinx的现场可编程门阵列平台完成硬件实现。通过仿真... 在现代通信中,高效可靠的调制算法可有效提升信号传输质量,进而改善通信系统整体性能。基于正交调制原理,设计并实现了一种码元速率可变的最小频移键控(MSK)正交调制方法。该方法在Xilinx的现场可编程门阵列平台完成硬件实现。通过仿真验证与上板测试,并与Matlab仿真结果进行对比,验证了所提方案的可行性。该调制器具有资源消耗少、参数控制灵活、成本低等优点,能实现1 kBd~40 MBd范围内任意码元速率的MSK信号调制。 展开更多
关键词 现场可编程门阵列 码率连续可变 通信算法 最小频移键控 正交调制
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生态环境法典编纂的“适度法典化”再造——基于系统观念的启示
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作者 许政敏 李莉娜 《湖南工业大学学报(社会科学版)》 2026年第1期104-112,共9页
系统观念是引领生态环境法典编纂的重要原则。基于系统观念,生态环境法典编纂的“适度法典化”再造,应在“整体论”与“系统构造原理”指引下,明确生态环境法典的“领域型法典”深层次性质,即在“领域性”基础上进一步明确其“行政立法... 系统观念是引领生态环境法典编纂的重要原则。基于系统观念,生态环境法典编纂的“适度法典化”再造,应在“整体论”与“系统构造原理”指引下,明确生态环境法典的“领域型法典”深层次性质,即在“领域性”基础上进一步明确其“行政立法领域”性质,从而确立法典编纂的中心目标应聚焦于生态环境行政领域,而非“诸法合体”。在系统运用编纂方法上,应明确“适度法典化”的“适度性”界限与程度,为完善法典编纂提供可操作性指导。在系统设计体例架构上,应在“适度性”上框定法典的架构范围及其法典化内容,适度提高法典的体系性。 展开更多
关键词 生态环境法典 “适度法典化” 系统观念 行政立法领域
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A deterministic method for designing near field and far field earthquakes 被引量:1
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作者 高孟潭 鄢家全 《Acta Seismologica Sinica(English Edition)》 CSCD 1995年第3期457-462,共6页
The earthquake environment of far field earthquake effects or near field earthquake effects are required to be considered in the Building Code (GBJ11-89), and a method to determine near field and far field earthquake ... The earthquake environment of far field earthquake effects or near field earthquake effects are required to be considered in the Building Code (GBJ11-89), and a method to determine near field and far field earthquake is proPosed based on the results of deterministic seismic zoning map(1977). The Seismic intensity Zoning Map of China (1990),which is currently used in China, was compiled using probabilistic approach. So the method determining the far field earthquake based on deterministic zoning method is not suitable. A new method is providedin this paper under the consideration of the essence of the near field and far field earthquake and the aPProach ofthe probabilistic seismic hazard analysis. The related problems of how to use the Building Code (GBJll-89) andthe Seismic intensity Zoning Map of China(1990) are solved. 展开更多
关键词 probebility intensity evaluation field earthuake building code
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Error Resilient Video Communication Based on Picture Level Adaptive Frame / Field Coding
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作者 徐巍炜 周凡 陈耀武 《Journal of Donghua University(English Edition)》 EI CAS 2013年第2期103-109,共7页
Packet loss protection method based on picture level adaptive frame /field coding (PAFF)was presented. Firstly,the end-to-end rate-distortion analysis for PAFF on the current frame was performed. Secondly,in order to ... Packet loss protection method based on picture level adaptive frame /field coding (PAFF)was presented. Firstly,the end-to-end rate-distortion analysis for PAFF on the current frame was performed. Secondly,in order to evaluate the severity of error propagation in the following frames,the error propagation intensity and human visual quality sensitivity of different areas were taken into consideration. It was followed by the quantification of relative importance. Finally,the proper coding mode was chosen utilizing an unequal comparison procedure. The simulation results show that the proposed method can improve peak signal-to-noise ratio (PSNR) up to 0. 9 dB and 1. 6 dB comparing with the field only and the dispersed flexible macro-block ordering (FMO)only methods respectively. 展开更多
关键词 error resilience field coding adaptive frame/field coding human visual system error control coding
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Optimal power allocation for complex field network coding scheme with the K-th best relay selection
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作者 Xi CAI Pingzhi FAN Qingchun CHEN 《Journal of Modern Transportation》 2012年第4期255-260,共6页
Wireless relay and network coding are two critical techniques to increase the reliability and throughput of wireless cooperative communication systems. In this paper, a complex field network coding (CFNC) scheme wit... Wireless relay and network coding are two critical techniques to increase the reliability and throughput of wireless cooperative communication systems. In this paper, a complex field network coding (CFNC) scheme with the K-th best relay selection (KBS) is proposed and investigated, wherein the K-th best relay is selected to forward the multiplexed signal to the destination. First, the upper bound of the symbol error probability (SEP), the diversity order, and the coding gain are derived for the CFNC scheme with KBS. Then, the coding gain is utilized as the optimized cri- terion to determine the optimal power allocation. It is validated through analysis and simulation that the CFNC scheme with KBS can achieve full diversity only when K=I, while the diversity order decreases with increasing parameter K, and the optimal power allocation can significantly improve the performance of the CFNC scheme with KBS. 展开更多
关键词 complex field network coding the K-th best relay selection power allocation
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基于FPGA实现的等效型SVPWM算法的研究
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作者 刘祥洋 徐海 +1 位作者 李浩宇 宿月 《电力电子技术》 2026年第4期108-114,共7页
本文针对等效型空间矢量脉宽调制(space vector pulse width modulation,SVPWM)的算法实现进行了深入研究。分析了对称规则采样的实现方法,并在对称规则采样思想的基础上,提出了等效型SVPWM的实现思路,推导了等效型SVPWM算法的实现过程... 本文针对等效型空间矢量脉宽调制(space vector pulse width modulation,SVPWM)的算法实现进行了深入研究。分析了对称规则采样的实现方法,并在对称规则采样思想的基础上,提出了等效型SVPWM的实现思路,推导了等效型SVPWM算法的实现过程。采用Simulink建模和现场可编程门阵列(field-programmable gate array,FPGA)代码转化的程序实现方案,大大缩短了算法的设计周期。通过Simulink仿真验证了等效型SVPWM算法的正确性。基于单片FPGA实现了等效型SVPWM算法的高速运算。搭建了硬件实验平台,在100 kHz开关频率下实现了基于SVPWM算法控制的三相逆变,验证了等效型SVPWM在高频环境下的实用性。 展开更多
关键词 等效型空间矢量脉宽调制 现场可编程门阵列 三相逆变 代码转化 对称规则采样
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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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Simulation of Electric Fields in Small Size Divertor Tokamak Plasma Edge
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作者 A. H. BEKHEIT 《Energy and Power Engineering》 2010年第1期39-45,共7页
The fluid simulation of Small Size Divertor Tokamak (SSDT) plasma edge by the B2-SOLPS5.0 2D [1] transport code gives the following results: First, in the vicinity of separatrix the radial electric field result is not... The fluid simulation of Small Size Divertor Tokamak (SSDT) plasma edge by the B2-SOLPS5.0 2D [1] transport code gives the following results: First, in the vicinity of separatrix the radial electric field result is not close to the neoclassical electric field. Second, the shear of radial electric field is independent on plasma parameters. Third, switching on poloidal drifts (E×B and diamagnetic drifts) leads to asymmetric parallel and poloidal fluxes from outer to inner plates and upper part of SOL for normal direction of toroidal magnetic field. Fourth, for the normal direction of toroidal magnetic, the radial electric field of SSDT is affected by the variation in temperature heating of plasma. Fifth, the parallel flux is directed from inner to outer plate in case of discharge without neutral beam injection (NBI). 展开更多
关键词 ELECTRIC field TRANSPORT codeS DIVERTOR TOKAMAK
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THE TRUE DIMENSION OF CERTAIN ALTERNANT CODES
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作者 Yue Dianwu Feng Guangzeng(Dept. of Telecom. Eng., Nanjing University of Posts & Telecommunications, Nanjing 210003) 《Journal of Electronics(China)》 2000年第4期352-356,共5页
By applying a result from geometric Goppa codes, due to H.Schtenoth, the true dimension of certain alternant codes is calculated. The results lead in many cases to an improvement of the usual lower bound for the dimen... By applying a result from geometric Goppa codes, due to H.Schtenoth, the true dimension of certain alternant codes is calculated. The results lead in many cases to an improvement of the usual lower bound for the dimension. 展开更多
关键词 Alternant code DIMENSION ALGEBRAIC funtion field Geometric Goppa code
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Simulation of small size divertor tokamak plasma edge under effect of toroidal magnetic field reversal
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作者 A. H. Bekheit 《Natural Science》 2011年第8期738-742,共5页
Asymmetries between the divertor legs of small size divertor (SSD) tokamak plasma edge are noticed to reverse when the direction of toroidal magnetic field is reversed. In the present paper the small size divertor tok... Asymmetries between the divertor legs of small size divertor (SSD) tokamak plasma edge are noticed to reverse when the direction of toroidal magnetic field is reversed. In the present paper the small size divertor tokamak plasma edge under effect of toroidal magnetic field reversal is simulated by B2SOLPS0.5.2D fluid transport code. The simulation demonstrate the following results: 1) Parallel (toroidal) flow flux and Mach number up to 0.6 at higher plasma density reverse with reverse toroidal magnetic direction in the edge plasma of small size divertor tokamak. 2) The radial electric field is toroidal magnetic direction independence in edge plasma of small size divertor tokamak. 3) For normal and reverse toroidal magnetic field, the strong ITB is located between the positions of the maximum and minimum values of the radial electric field shear. 4) Simulation result shows that, the structure of radial electric field at high field side (HFS) and low field side (LFS) is different. This difference result from the change in the parallel flux flows in the scrape off layer (SOL) to plasma core through separatrix. 5) At a region of strong radial electric field shear, a large reduction of poloidal rotation was observed. 6) The poloidal rotation is toroidal magnetic field direction dependence. 展开更多
关键词 REVERSE TOROIDAL field B2SOLPS0.5.2D code ITB
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基于公钥思想的非对称Hopping Code系统编码芯片设计
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作者 柯建东 祝叶华 +1 位作者 刘文江 戎蒙恬 《微电子学与计算机》 CSCD 北大核心 2006年第6期138-140,144,共4页
针对应用于遥控或命令辨别场合的跳码系统,提出了一种新型的非对称跳码算法。该跳码系统的加解密算法基于有限域GF(2m)上的多项式运算,采用了随机数发生器,能够完成汽车电子钥匙等遥控或命令辨别场合的跳码功能,并达到较高的安全性。文... 针对应用于遥控或命令辨别场合的跳码系统,提出了一种新型的非对称跳码算法。该跳码系统的加解密算法基于有限域GF(2m)上的多项式运算,采用了随机数发生器,能够完成汽车电子钥匙等遥控或命令辨别场合的跳码功能,并达到较高的安全性。文章主要介绍了加解密模块及发送端芯片的设计与实现。 展开更多
关键词 跳码 加解密 编码发送芯片 有限域上多项式 超大规模集成电路
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