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一种分数前缀XML编码方案 被引量:5
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作者 刘先锋 周舟 +1 位作者 刘萍 张楚才 《计算机工程》 CAS CSCD 2012年第12期29-31,共3页
针对XML数据的更新与查询问题,提出一种分数前缀编码方案(FPES)。将分数引入LSDX前缀编码中,在2个分数间可插入无穷多个分数,支持XML节点数据的无限更新,并可表示祖先后裔关系、父子关系和兄弟关系,避免二次编码。实验结果表明,FPES与L... 针对XML数据的更新与查询问题,提出一种分数前缀编码方案(FPES)。将分数引入LSDX前缀编码中,在2个分数间可插入无穷多个分数,支持XML节点数据的无限更新,并可表示祖先后裔关系、父子关系和兄弟关系,避免二次编码。实验结果表明,FPES与LSDX相比,查询效率较高;与分数编码相比,编码时间与插入节点的时间较少。 展开更多
关键词 可扩展标识语言 编码方案 分数前缀编码方案 分数编码 XML数据更新
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基于分数的动态前缀XML编码方案 被引量:3
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作者 姚保峰 马程 +2 位作者 谢娜 戚晓明 郭有强 《商丘师范学院学报》 CAS 2014年第3期71-74,78,共5页
针对现有的XML文档树编码方案均不能很好地支持XML文档动态更新问题,提出一种基于分数的动态前缀编码DPEF.在保留Dewey编码优秀特性的基础上,利用分数的无限扩展性,实现了在无需二次编码的情况下对XML文档进行动态更新.实验结果表明,该... 针对现有的XML文档树编码方案均不能很好地支持XML文档动态更新问题,提出一种基于分数的动态前缀编码DPEF.在保留Dewey编码优秀特性的基础上,利用分数的无限扩展性,实现了在无需二次编码的情况下对XML文档进行动态更新.实验结果表明,该编码相对于已有的前缀编码方案具有更好的时间和空间性能. 展开更多
关键词 XML编码 分数编码 DEWEY编码 XML数据更新
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一种快速的分数位平面编码方法及其电路结构 被引量:1
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作者 许超 韩彦菊 《计算机学报》 EI CSCD 北大核心 2005年第10期1650-1656,共7页
JPEG2000是新一代图像压缩国际标准.它在位平面编码技术的基础上,进一步采用了分数位平面编码技术.分数位平面编码使编码输出的码流具有更高的渐进性和抗干扰性,但是,它使编码的运算量大幅度增加.为实现快速编码,该文提出一种位平面、... JPEG2000是新一代图像压缩国际标准.它在位平面编码技术的基础上,进一步采用了分数位平面编码技术.分数位平面编码使编码输出的码流具有更高的渐进性和抗干扰性,但是,它使编码的运算量大幅度增加.为实现快速编码,该文提出一种位平面、过程双重并行编码方法,可以大幅度提高编码速度.另外,为降低大数量并行编码消耗的电路资源量,文中提出一种局部模块并行电路结构.实验结果显示,该文方法的编码速度约为每时钟编码一个系数,比已有技术提高约15倍.在FPGA电路平台上,只需要约4·2K的逻辑单元,因此它是一种可以通过低成本集成电路实现的快速分数位平面编码技术. 展开更多
关键词 JPEG2000 分数位平面编码 电路结构
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JPEG2000分数位平面编码器的FPGA电路实现 被引量:1
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作者 韩彦菊 许超 《计算机工程》 EI CAS CSCD 北大核心 2005年第15期183-185,共3页
分数位平面编码是JPEG2000图像压缩国际标准中的核心技术之一,是影响JPEG2000编码速度的最关键部分。基于位平面、过程双重并行(BPDP)的编码方法和局部模块并行结构,利用FPGA电路设计了JPEG2000分数位平面编码器。电路仅需要约5100个逻... 分数位平面编码是JPEG2000图像压缩国际标准中的核心技术之一,是影响JPEG2000编码速度的最关键部分。基于位平面、过程双重并行(BPDP)的编码方法和局部模块并行结构,利用FPGA电路设计了JPEG2000分数位平面编码器。电路仅需要约5100个逻辑单元,当工作在54MHz时,每秒可以编码30幅尺寸约为1500×1200的图像。 展开更多
关键词 分数位平面编码 JPEG2000 双重并行 FPGA
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一种基于间隔因子的动态编码方案
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作者 成艳 郭学俊 张鹏程 《信息技术》 2013年第12期18-22,26,共6页
传统的前缀编码和区间编码在XML数据更新时都需要重新编码,当文档更新频繁时这种消耗是无法承受的,已有的动态编码大多不能完全支持动态更新。在FPES编码方法基础上采用一种基于间隔因子的分数前缀编码方案(Interval Fraction Prefix La... 传统的前缀编码和区间编码在XML数据更新时都需要重新编码,当文档更新频繁时这种消耗是无法承受的,已有的动态编码大多不能完全支持动态更新。在FPES编码方法基础上采用一种基于间隔因子的分数前缀编码方案(Interval Fraction Prefix Labeling Scheme,IFPL),利用间隔因子解决预留空间用完的问题,使得其在特殊情况下也不需要重新编码,二次编码率为零。实验表明,相对于FPES文中的IFPL方案以一定的空间消耗换取了对文档动态更新的完全支持,特别是在文档规模越大时优势越明显。 展开更多
关键词 间隔因子 分数编码 前缀编码 动态更新
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完全支持数据更新的XML压缩编码 被引量:1
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作者 周舟 刘先锋 +1 位作者 刘萍 张楚才 《湖南师范大学自然科学学报》 CAS 北大核心 2011年第6期21-25,共5页
为了有效地更新和查询XML数据,提出了一种新的XML编码方案—分数路径编码(简写为FAPE).FAPE充分利用在两个分数间可以插入无穷多个分数这一特点,支持XML结点数据的无限更新,同时FAPE将结点的相关信息保存在相应的表中,避免记录重复的信... 为了有效地更新和查询XML数据,提出了一种新的XML编码方案—分数路径编码(简写为FAPE).FAPE充分利用在两个分数间可以插入无穷多个分数这一特点,支持XML结点数据的无限更新,同时FAPE将结点的相关信息保存在相应的表中,避免记录重复的信息.实验表明:FAPE节省了存储空间,提高了查询效率,更新所花的时间更少. 展开更多
关键词 编码方案 分数路径编码 FAPE XML数据更新 数据查询
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A compound objective reconfiguration of distribution networks using hierarchical encoded particle swarm optimization 被引量:3
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作者 WEN Juan TAN Yang-hong +1 位作者 JIANG Lin XU Zu-hua 《Journal of Central South University》 SCIE EI CAS CSCD 2018年第3期600-615,共16页
With the development of automation in smart grids,network reconfiguration is becoming a feasible approach for improving the operation of distribution systems.A novel reconfiguration strategy was presented to get the o... With the development of automation in smart grids,network reconfiguration is becoming a feasible approach for improving the operation of distribution systems.A novel reconfiguration strategy was presented to get the optimal configuration of improving economy of the system,and then identifying the important nodes.In this strategy,the objectives increase the node importance degree and decrease the active power loss subjected to operational constraints.A compound objective function with weight coefficients is formulated to balance the conflict of the objectives.Then a novel quantum particle swarm optimization based on loop switches hierarchical encoded was employed to address the compound objective reconfiguration problem.Its main contribution is the presentation of the hierarchical encoded scheme which is used to generate the population swarm particles of representing only radial connected solutions.Because the candidate solutions are feasible,the search efficiency would improve dramatically during the optimization process without tedious topology verification.To validate the proposed strategy,simulations are carried out on the test systems.The results are compared with other techniques in order to evaluate the performance of the proposed method. 展开更多
关键词 distribution network reconfiguration node importance degree compound objective function hierarchical encoded
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Compressing and Coding Method of Seismic Data
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作者 赵学军 郑宇 +2 位作者 宁书年 郭俊霞 岳俊梅 《Journal of China University of Mining and Technology》 2002年第1期95-99,共5页
Aiming at the characteristics of the seismic exploration signals, the paper studies the image coding technology, the coding standard and algorithm, brings forward a new scheme of admixing coding for seismic data compr... Aiming at the characteristics of the seismic exploration signals, the paper studies the image coding technology, the coding standard and algorithm, brings forward a new scheme of admixing coding for seismic data compression. Based on it, a set of seismic data compression software has been developed. 展开更多
关键词 data compression wavelet transform encode IMAGE
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A Compression Algorithm of Hyperspectral Remote Sensing Image Based on 3-D Wavelet-Fractal Coder
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作者 邹毅 潘伟 敖露 《Journal of Donghua University(English Edition)》 EI CAS 2010年第2期229-232,共4页
In this paper, the 3-D Wavelet-Fractal coder was used to compress the hyperspectral remote sensing image, which is a combination of 3-D improved set partitioning in hierarchical trees (SPIHT) coding and 3-D fractal ... In this paper, the 3-D Wavelet-Fractal coder was used to compress the hyperspectral remote sensing image, which is a combination of 3-D improved set partitioning in hierarchical trees (SPIHT) coding and 3-D fractal coding. Hyperspectral image date cube was first translated by 3-D wavelet and the 3-D fractal compression ceding was applied to lowest frequency subband. The remaining coefficients of higher frequency sub-bands were encoding by 3-D improved SPIHT. We used the block set instead of the hierarchical trees to enhance SPIHT's flexibility. The classical eight kinds of affme transformations in 2-D fractal image compression were generalized to nineteen for the 3-D fractal image compression. The new compression method had been tested on MATLAB. The experiment results indicate that we can gain high compression ratios and the information loss is acceptable. 展开更多
关键词 image compression three dimensional improved SPIHT fractal compression coding HYPERSPECTRAL
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In-Network Puncturing for Delay-Efficient Rate Control of Distributed Video Coding in Wireless Video Sensor Networks 被引量:1
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作者 Zhang Haitao Ma Huadong 《China Communications》 SCIE CSCD 2012年第6期45-54,共10页
Wyner-Ziv Video Coding (WZVC) is considered as a promising video coding scheme for Wireless Video Sensor Networks (WVSNs) due to its high compression efficiency and error resilience functionalities, as well as its... Wyner-Ziv Video Coding (WZVC) is considered as a promising video coding scheme for Wireless Video Sensor Networks (WVSNs) due to its high compression efficiency and error resilience functionalities, as well as its low encoding complex- ity. To achieve a good Rate-Distortion (R-D) per- formance, the current WZVC paradi^prls usually a- dopt an end-to-end rate control scheme in which the decoder repeatedly requests the additional deco- ding data from the encoder for decoding Wyner-Ziv frames. Therefore, the waiting time of the additional decoding data is especially long in multihop WVSNs. In this paper, we propose a novel pro- gressive in-network rate control scheme for WZVC. The proposed in-network puncturing-based rate control scheme transfers the partial channel codes puncturing task from the encoder to the relay nodes. Then, the decoder can request the addition- al decoding data from the relay nodes instead of the encoder, and the total waiting time for deco- ding Wyner-Ziv frames is reduced consequently. Simulation results validate the proposed rate con- trol scheme. 展开更多
关键词 wireless video sensor networks dis-tributed video coding WZVC rate control delay-efficient
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Numerical Classification of Brevibacterium and Related Genera Using Linocin M18 Bacteriocin
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作者 Essra Gh. Al-Sammak 《Journal of Life Sciences》 2013年第4期382-389,共8页
Fifty bacterial strains isolated from dairy product, skin and blood from cancer and kidney failure dialysis patients were identified to 22 species and the following genera: Brevibacterium, Corynebacterium, Arthrobact... Fifty bacterial strains isolated from dairy product, skin and blood from cancer and kidney failure dialysis patients were identified to 22 species and the following genera: Brevibacterium, Corynebacterium, Arthrobacter, Actinomyces, Exiguobacterium, Kocuria, Micrococcus, Rothia, Rhodococcus and classified numerically using a set of 52 phenetic characteristics, using simple matching coefficient (Ssm) and clustering method of unweighted average linkage between groups by SPSS program. They were also grouped to 7 main clusters and 29 sub-clusters in the hierarchical tree. Twelve isolates of the different species from the genera Brevibacterium, Arthrobacter, Corynebacterium, Kocuria, Rhodococcus, Rothia were selected from the taxonomic clusters and probed for lin gene by peR. One species Kocuria rhizophila which inhibited most of the test organism did not have lin gene in the chromosome while the species Corynebacterium glucuronolyticum, Arthrobacter comminsii, Arthrobacter oxydans have the lin gene. Our results establish a wide distribution of the structural gene encoding this Iinocin M 18 within coryneform bacteria and also in the genus Kocuria. 展开更多
关键词 NUMERICAL CLASSIFICATION BREVIBACTERIUM Iinocin M18.
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A SEMI-OPEN-LOOP CODING MODE SELECTION ALGORITHM BASED ON EFM AND SELECTED AMR-WB+ FEATURES
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作者 Hong Ying Zhao Shenghui Kuang Jingming 《Journal of Electronics(China)》 2009年第2期274-278,共5页
To solve the problems of the AMR-WB+(Extended Adaptive Multi-Rate-WideBand) semi-open-loop coding mode selection algorithm,features for ACELP(Algebraic Code Excited Linear Prediction) and TCX(Transform Coded eXcitatio... To solve the problems of the AMR-WB+(Extended Adaptive Multi-Rate-WideBand) semi-open-loop coding mode selection algorithm,features for ACELP(Algebraic Code Excited Linear Prediction) and TCX(Transform Coded eXcitation) classification are investigated.11 classifying features in the AMR-WB+ codec are selected and 2 novel classifying features,i.e.,EFM(Energy Flatness Measurement) and stdEFM(standard deviation of EFM),are proposed.Consequently,a novel semi-open-loop mode selection algorithm based on EFM and selected AMR-WB+ features is proposed.The results of classifying test and listening test show that the performance of the novel algorithm is much better than that of the AMR-WB+ semi-open-loop coding mode selection algorithm. 展开更多
关键词 Speech/Audio Semi-open-loop coding mode selection Features selection Energy Flat-ness Measurement(EFM)
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Algebraic encoding scheme for aperture 3 hexagonal discrete global grid system 被引量:5
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作者 BEN Jin LI YaLu +2 位作者 ZHOU ChengHu WANG Rui DU LingYu 《Science China Earth Sciences》 SCIE EI CAS CSCD 2018年第2期215-227,共13页
Discrete Global Grid Systems(DGGSs) are spatial references that use a hierarchical tessellation of cells to partition and address the entire globe. They provide an organizational structure that permits fast integratio... Discrete Global Grid Systems(DGGSs) are spatial references that use a hierarchical tessellation of cells to partition and address the entire globe. They provide an organizational structure that permits fast integration between multiple sources of large and variable geospatial data sufficient for visualization and analysis. Despite a significant body of research supporting hexagonal DGGSs as the superior choice, the application thereof has been hindered owing in part to the lack of a rational hierarchy with an efficient addressing system. This paper presents an algebraic model of encoding scheme for the Aperture 3 Hexagonal(A3H) DGGS. Firstly, the definition of a grid cell, which is composed of vertices, edges, and a center, is introduced to describe fundamental elements of grids. Secondly, by identifying the grid cell with its center, this paper proves that cell centers at different levels can be represented exactly using a mixed positional number system in the complex plane through the recursive geometric relationship between two successive levels, which reveals that grid cells are essentially special complex radix numbers. Thirdly, it is shown that through the recursive geometric relationship of successive odd or even levels, the mixed positional number system can also be applied to uniquely represent cell centers at different levels under specific constraint conditions, according to which the encoding scheme is designed. Finally, it is shown that by extending the scheme to 20 triangular faces of the regular icosahedron,multi-resolution grids on closed surfaces of the icosahedron are addressed perfectly. Contrast experiments show that the proposed encoding scheme has the advantages of theoretical rigor and high programming efficiency and that the efficiency of cross-face adjacent cell searching is 242.9 times that of a similar scheme. Moreover, the proposed complex radix number representation is an ideal formalized description tool for grid systems. The research ideas introduced herein can be used to create a universal theoretical framework for DGGSs. 展开更多
关键词 Discrete Global Grid System HEXAGON Positional number system Algebraic encoding
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Deterministic quantum communication using the symmetric W state 被引量:9
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作者 TSAI Chia-Wei HWANG Tzonelih 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2013年第10期1903-1908,共6页
This study proposes a new coding function for the symmetric W state. Based on the new coding function, a theoretical protocol of deterministic quanama communication (DQC) is proposed. The sender can use the proposed... This study proposes a new coding function for the symmetric W state. Based on the new coding function, a theoretical protocol of deterministic quanama communication (DQC) is proposed. The sender can use the proposed coding function to encode his/her message, and the receiver can perform the imperfect Bell measurement to obtain the sender's message. In comparison to the existing DQC protocols that also use the W class state, the proposed protocol is more efficient and also more practical within today's technology. Moreover, the security of this protocol is analyzed to show that any eavesdropper will be detected with a very high probability under both the ideal and the noisy quantum channel. 展开更多
关键词 deterministic quantum communication symmetric W state imperfect Bell measurement
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Improving the efficiency of quantum hash function by dense coding of coin operators in discrete-time quantum walk 被引量:1
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作者 YuGuang Yang YuChen Zhang +3 位作者 Gang Xu XiuBo Chen Yi-Hua Zhou WeiMin Shi 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS CSCD 2018年第3期18-25,共8页
Li et al. first proposed a quantum hash function(QHF) in a quantum-walk architecture. In their scheme, two two-particle interactions, i.e., I interaction and π-phase interaction are introduced and the choice of I or ... Li et al. first proposed a quantum hash function(QHF) in a quantum-walk architecture. In their scheme, two two-particle interactions, i.e., I interaction and π-phase interaction are introduced and the choice of I or π-phase interactions at each iteration depends on a message bit. In this paper, we propose an efficient QHF by dense coding of coin operators in discrete-time quantum walk. Compared with existing QHFs, our protocol has the following advantages: the efficiency of the QHF can be doubled and even more; only one particle is enough and two-particle interactions are unnecessary so that quantum resources are saved. It is a clue to apply the dense coding technique to quantum cryptographic protocols, especially to the applications with restricted quantum resources. 展开更多
关键词 quantum cryptography quantum walk discrete-time quantum walk COLLISION birthday attack
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Weak Correlation Dictionary Construction Method for Sparse Coding
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作者 龙海霞 卓力 +1 位作者 屈盼玲 张菁 《Journal of Shanghai Jiaotong university(Science)》 EI 2017年第1期77-81,共5页
For sparse coding, the weaker the correlation of dictionary atoms is, the better the representation capacity of dictionary will be. A weak correlation dictionary construction method for sparse coding has been proposed... For sparse coding, the weaker the correlation of dictionary atoms is, the better the representation capacity of dictionary will be. A weak correlation dictionary construction method for sparse coding has been proposed in this paper. Firstly, a new dictionary atom initialization is proposed in which data samples with weak correlation are selected as the initial dictionary atoms in order to effectively reduce the correlation among them.Then, in the process of dictionary learning, the correlation between atoms has been measured by correlation coefficient, and strong correlation atoms have been eliminated and replaced by weak correlation atoms in order to improve the representation capacity of the dictionary. An image classification scheme has been achieved by applying the weak correlation dictionary construction method proposed in this paper. Experimental results show that, the proposed method averagely improves image classification accuracy by more than 2%, compared to sparse coding spatial pyramid matching(Sc SPM) and other existing methods for image classification on the datasets of Caltech-101, Scene-15, etc. 展开更多
关键词 image classification sparse coding correlation coefficient dictionary initialized TP 391.1 A
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