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一种结构化P2P系统的负载平衡算法

计算机科学 2010年第4期37卷 82-85页

作者：魏文红向菲王文丰王高才东莞理工学院计算机学院东莞523808 河南科技大学电子信息工程学院洛阳471003 南昌工程学院计算机科学与技术系南昌330099 广西大学计算机与电子信息学院南宁530004

在结构化P2P系统中,由于使用分布式散列表,各节点能够达到基本的负载平衡。但是,各个节点由于承担负载的能力不同和数据的存取存在"热点"现象,因此仍然存在负载不平衡的情况。针对这一缺点,采用局部信息调整负载的方法,提出了分布式负... 详细信息

在结构化P2P系统中,由于使用分布式散列表,各节点能够达到基本的负载平衡。但是,各个节点由于承担负载的能力不同和数据的存取存在"热点"现象,因此仍然存在负载不平衡的情况。针对这一缺点,采用局部信息调整负载的方法,提出了分布式负载平衡算法,从而避免了单点失效问题,同时算法的实现更为简单。

关键词：分布式哈希表 P2P系统负载平衡虚拟服务器

Accelerating BP-Based Iterative Low-Density Parity-Check Decoding by Modified Vertical and Horizontal Processes

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Journal of Southwest Jiaotong university(English Edition) 2009年第4期17卷 275-282页

作者：陈婧文仰枫帆罗琳 THO Le-Ngoc college of Information science and technology Nanjing University of Aeronautics and Astronautics college of Information science and Engineering Southeast University Department of Electrical and computer Engineering McGill UniversityMontreal

Two modified BP algorithms related to vertical and horizontal processes are proposed to accelerate iterative low-density parity- check （LDPC） decoding over an additive white Gaussian noise （AWGN） channel, where the newly updated extrinsic information is immediately used in the current decoding round. Theoretical analysis and simulation results demonstrate that both the modified approaches provide significant performance improvements over the traditional BP algorithm with almost no additional decoding complexity. The proposed algorithm with modified horizontal process offers even better performance than another algorithm with the modified horizontal process. The two modified BP algorithms are very promising in practical communications since both can achieve an excellent trade-off between the performance and decoding complexity.

关键词： LDPC codes Iterative decoding BP algorithm Extrinsic information Horizontal process Vertical process

A lattice-based signcryption scheme without random oracles

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Frontiers of computer science 2014年第4期8卷 667-675页

作者： Xiuhua LU qiaoyan wen Zhengping JIN Licheng WANG Chunli yang State Key Laboratory of Networking and Switching technology Beijing University of Posts and Telecommunications Beijing 100876 China Mathematics and Information science Langfang Teachers University Langfang 065000 China Information Security Center Beijing University of Posts and Telecommunications Beijing 100876 China

In order to achieve secure signcryption schemes in the quantum era, Li Fagen et al. [Concurrency and Computation： Practice and Experience, 2012, 25（4）： 2112-2122] and Wang Fenghe et al. [Applied Mathematics ＆ Information sciences, 2012, 6（1）： 23.28] have independently extended the concept of signcryption to lattice-based cryptography. However, their schemes are only secure under the random or- acle model. In this paper, we present a lattice-based signcryp- tion scheme which is secure under the standard model. We prove that our scheme achieves indistinguishability against adaptive chosen-ciphertext attacks （IND-CCA2） under the learning with errors （LWE） assumption and existential unforgeability against adaptive chosen-message attacks （EUF- CMA） under the small integer solution （SIS） assumption.

关键词： signcryption standard model lattice-based cryptography learning with errors problem small integer solution problem

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基于数字全息的图像置乱的研究

山东大学学报（理学版） 2005年第5期40卷 93-96页

作者：戚文静赵敬山东建筑工程学院计算机科学与技术系山东济南250101 中华女子学院山东分院计算机系山东济南250001

基于用数字全息对图像进行置乱及复原的基本原理,提出了一种基于数字全息的图像置乱方法,并通过实验证明了本方法的置乱和复原效果.

关键词：数字全息图像置乱随机位相函数傅立叶变换

Quantum position verification in bounded-attack-frequencymodel

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science china(Physics,Mechanics & Astronomy) 2016年第11期59卷 17-27页

作者： Fei Gao Bin Liu qiaoyan wen State Key Laboratory of Networking and Switching technology Beijing University of Posts and Telecommunications college of computer science Chongqing University

In 2011, Buhrman et al. proved that it is impossible to design an unconditionally secure quantum position verification(QPV)protocol if the adversaries are allowed to previously share unlimited entanglements. Afterwards, people started to design secure QPV protocols in practical settings, e.g. the bounded-storage model, where the adversaries' pre-shared entangled resources are supposed to be limited. Here we focus on another practical factor that it is very difficult for the adversaries to perform attack operations with unlimitedly high frequency. Concretely, we present a new kind of QPV protocols, called non-simultaneous *** we prove the security of a specific non-simultaneous QPV protocol with the assumption that the frequency of the adversaries' attack operations is bounded, but no assumptions on their pre-shared entanglements or quantum storage. Actually, in our nonsimultaneous protocol, the information whether there comes a signal at present time is also a piece of command. It renders the adversaries "blind", that is, they have to execute attack operations with unlimitedly high frequency no matter whether a signal arrives, which implies the non-simultaneous QPV is also secure in the bounded-storage model.

关键词： quantum cryptography position-based cryptography quantum position verification

Research on the Willingness to Accept Compensation and Compensation Sharing of Returning Land for Farming to Forestry in Zhangjiakou and Chengde Region

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Meteorological and Environmental Research 2011年第5期2卷 41-44页

作者： WANG Yan-xia1,CHEN Xu-dong1,ZHANG Su-juan1,BAI Jie2,ZHANG Yi-wen3.1.Institute of Geographical science,Hebei Academy of science,Shijiazhuang 050011,{3. 2.computer Department,Hebei Vocational college of Politics and Law,Shijiazhuang 050081,{3. 3.college of Resources and Environment science,Hebei Normal university,Hebei Key Laboratory of Environmental Change and Ecological Construction,Shijiazhuang 050016,{3.

[Objective] The aim was to study the willingness to accept compensation and compensation sharing of returning land for farming to forestry in Zhangjiakou and Chengde region.[Method] Based on the investigation of farmers’ willingness to accept ecological compensation in Zhangjiakou and Chengde region,farmers’ willingness to accept compensation was quantized,and the calculation model of sharing rate of ecological compensation was established,finally the sharing rate of ecological compensation was calculated choosing water supply quantity as reference.[Result] Farmers’ willingness to accept compensation in Zhangjiakou and Chengde region was 2 740.5 yuan/(hm2·a),and returned farmland area was 429 700 hm2 in 2008,so the willingness to accept ecological compensation was up to 1.178 billion yuan/*** addition,the ecological compensation sharing rate of government was 3..60% in beijing,42.75% in Tianjing and 19.64% in Tangshan,and their ecological compensation funds were 443.504 and 23. million yuan,respectively.[Conclusion] The study could provide important foundation for the establishment of ecological compensation standard and implementation of ecological compensation in Zhangjiakou and Chengde region.

关键词： Zhangjiakou Chengde Ecological compensation Willingness to accept compensation Sharing rate of compensation china

QKD-based quantum private query without a failure probability

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science china(Physics,Mechanics & Astronomy) 2015年第10期58卷 12-17页

作者： LIU Bin GAO Fei HUANG Wei wen qiaoyan State Key Laboratory of Networking and Switching technology Beijing University of Posts and Telecommunications college of computer science Chongqing University

In this paper, we present a quantum-key-distribution(QKD)-based quantum private query(QPQ) protocol utilizing single-photon signal of multiple optical pulses. It maintains the advantages of the QKD-based QPQ, i.e., easy to implement and loss tolerant. In addition, different from the situations in the previous QKD-based QPQ protocols, in our protocol, the number of the items an honest user will obtain is always one and the failure probability is always zero. This characteristic not only improves the stability(in the sense that, ignoring the noise and the attack, the protocol would always succeed), but also benefits the privacy of the database(since the database will no more reveal additional secrets to the honest users). Furthermore, for the user's privacy, the proposed protocol is cheat sensitive, and for security of the database, we obtain an upper bound for the leaked information of the database in theory.

关键词： quantum private query quantum key distribution single-photon signal

工程造价领域分布式数据库加锁与刷新机制研究

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山东农业大学学报（自然科学版） 2004年第4期35卷 560-564页

作者：徐学东魏光村温凤荣蒋严冰山东农业大学水利土木工程学院山东泰安271018 山东科技大学信息工程系山东泰安271019 山东农业大学经济管理学院山东泰安271018 北京大学计算机系北京100871

本文根据工程预算领域的实际情况 ,特别是结合中小型建筑企业的特点 ,运用数据库理论与技术以及构件技术 ,阐述了分布式数据库加锁与刷新构件的实现原理与实现机制 ,并将其应用到“造价工程师 2 0 0 4网络版”的研制开发中 ,取得了满意... 详细信息

本文根据工程预算领域的实际情况 ,特别是结合中小型建筑企业的特点 ,运用数据库理论与技术以及构件技术 ,阐述了分布式数据库加锁与刷新构件的实现原理与实现机制 ,并将其应用到“造价工程师 2 0 0 4网络版”的研制开发中 ,取得了满意的结果。该分布式数据库加锁与刷新构件可以应用到系统中的各个模块中 ,具有复用性强、安全可靠、简单易用等特点 ,并在一定范围内推动了工程造价领域自动化、数字化的进程。

关键词：加锁分布式数据库刷新机制构件技术数据库理论进程实现原理工程造价中小型建筑造价工程师

Data embedding based on pixel value differencing and modulus function using indeterminate equation

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The Journal of china Universities of Posts and Telecommunications 2015年第1期22卷 95-100页

作者： Wang Zhao Zhang Jie Liao Xin wen qiaoyan School of science Beijing University of Posts and Telecommunications college of computer science and Electronic Engineering Hunan University State Key Laboratory of Networking and Switching technology Beijing University of Posts and Telecommunications

An effective data hiding method based on pixel value differencing （PVD） and modulus function （MF） PVD （MF-PVD） was proposed. MF-PVD method was derived by Wang et al in which the MF was employed to adjust the remainder of two pixels for data embedding and extraction. In the proposed method, a new remainder function in a more general form is defined by selecting proper parameters, in which an indeterminate equation is constructed and an optimal solution is applied to revise the pixels. This strategy leads to a significant image distortion reduction compared with the original method. The experiment reveals that, by preserving the original embedding capacity, the method provides better embedding efficiency than both MF-PVD and PVD methods.

关键词： pixel value differencing modulus function indeterminate equation data embedding