基于用户与节点规模的微博突发话题传播预测算法

突发话题传播建模与预测的主要目的是对网络中可能产生不良影响的、紧急性突发事件的后续传播进行控制。目前微博网络中的话题传播与预测研究尚处于起步阶段。通过对病毒传染模型、消息传播模型以及话题传播模型的深入研究,提出一种基于微博粉丝关系、用户活跃度和影响力的话题传播模型,将微博用户集合划分为感染用户、易染用户和免疫用户,分析感染用户和易染用户的粉丝关系,预测下个时间窗口内被感染的用户规模。沿用话题传播模型研究中的“内外场强”概念,通过研究发现“内场强”和“外场强”有特定的比例关系,基于用户群的规模大小,分别提出基于用户和节点规模的话题传播预测算法。相关实验表明,基于用户的算法预测更为准确但是时间复杂度较高,基于节点规模的算法则更适合大规模数据集的处理。     

基于多特征融合的微博用户权威度定量评价方法

微博用户权威度是评价微博信息可靠性的重要因素之一.本文针对微博用户权威度的定量计算提出了一种基于多特征融合的微博用户权威度定量评价模型.首先,提出了用户权威度的概念,将其定义为用户影响力和被信服度两部分组成;在暂不考虑用户领域影响因子的情况下,基于新浪微博数据,抽取出微博用户信息传播影响力、用户信息完整度、用户活跃度以及用户平台认证指数4项评价特征,以构建了用户权威度定量计算模型;然后,采用层次分析法对所构建模型的4项评价特征的权值进行确定,并分别给出了4项评价特征的提取算法.同时,在用户关注关系网络的基础上,提出了一种基于用户被关注价值的用户信息传播影响力模型UIRank,并通过实验验证了其比PageRank算法更加有效.实验结果表明,本文提出的微博用户权威度定量计算模型比较合理,为用户权威度的定量评价提供了一种可行的解决方案.     

突发环境事件中微博影响力的预测研究

构建突发环境事件中微博影响力预测模型,有助于相关部门及早发现问题,并采取行动,保障网络舆情平稳发展。因此,本文以“xx突发环境事件”为研究对象,根据微博转发、点赞和评论次数衡量其影响力,选取微博用户、内容、时间特征,建立基于AdaBoost算法的微博影响力预测模型,并对微博特征重要性进行分析,结果表明该模型的预测精度可达到93.2%,能够较好地完成预测任务。此外,微博的内容、时间特征、用户基本信息、用户活跃度均对微博影响力产生作用,长文本的、通知类的微博影响力更高,白天发布的微博影响力要比晚上发布的高,政府媒体用户和大V用户发布的微博影响力更高,原创度高的用户发布的微博影响力也会更高。     

基于Hadoop的微博用户影响力排名算法设计

微博用户影响力排名现主要以粉丝数为依据,但这种方法并不公正,针对这一问题,文中基于PageRank算法,提出一种基于PsoRank的评价算法。算法从用户自身质量及其粉丝质量入手,以粉丝数量、粉丝质量、评论率、转发率为因素,计算用户PIR值。最后,算法在Hadoop平台下实现,结果表明该算法相对于粉丝数量排名算法以及PageRank算法更能够反映用户真正的影响力。     

一种基于MapReduce架构的微博用户影响力评价算法的设计与实现

随着互联网的高速发展和Web2.0时代的到来,微博用户正以惊人的速度在增长.新浪微博现以粉丝数作为用户排名的依据,在僵尸粉和大量低使用率帐号的影响下,这种简单的排名依据难以表征用户的影响力.本文以海量新浪微博数据为分析对象,在分布式系统上构建微博用户的影响力评价模型.文章主要以微博用户的转发网络计算微博用户的微博影响力,再利用关注关系计算微博用户的潜在影响力,最后合成微博用户影响力的评价模型.实验及分析表明,该评价方法在微博服务中能有效的反映微博用户的真实影响力,适用于度量微博用户的影响力.     

基于受限非负张量分解的用户社会影响力分析

针对传统社会影响力分析方法未能充分考虑观点和话题信息等问题,提出了一种基于受限非负张量分解的用户社会影响力分析方法。首先把社交媒介用户相互评论关系自然地表示成三阶张量,然后通过拉普拉斯话题约束矩阵控制张量分解过程,最后根据分解得到的潜在因子度量用户观点社会影响力。该方法的优点是能有效地从受限张量分解结果中检索出给定话题下用户的社会影响力,同时保持其社会影响力的极性分布。实验结果表明,该方法的性能优于OOLAM和TwitterRank等基准算法。     

基于内容和评论及时性的微博影响力用户检测算法

以评论内容关键字和用户之间的评论关系为基础,结合评论及时性在微博影响力用户检测中的重要作用,研究如何有效获取微博中最有影响力用户的问题,基于Page Rank经典算法提出了基于评论内容相似性和评论及时性的微博影响力用户检测算法(Com Rank)。算法首先对每条评论信息进行分割处理,获取关键字并记录评论生成时间;然后基于评论内容关键字相似性计算评论内容相似性;再次,结合评论及时性计算评论关系权值;最后使用Com Rank算法检测最有影响力的微博用户。真实数据集上的实验结果验证了该方法的有效性。     

微博客意见领袖识别的研究

基于对已有成果的借鉴,从用户影响力和活跃度两方面出发,主要针对微博中存在的＂互关注＂风气及＂即逝意见领袖＂问题,构建了用户领袖值评分指标体系,并提出了用户领袖值的量化定义,最后在获取的新浪微博真实数据集上进行了验证,确保了本文识别机制的有效性。     

基于用户行为和结构洞的用户影响力评价模型

针对目前大多数用户影响力度量方法未能充分考虑非冗余信息的问题,结合结构洞原理,构建基于用户行为和结构洞的用户影响力评价模型。对用户行为进行量化,将其融入到网络边权中,并在此基础上对结构洞评价方法——网络约束系数进行改进,解决其未考虑用户行为对网络边权的影响,以及节点与邻近节点、次邻近节点三层拓扑关系的问题,最后构建用户影响力综合评价模型。通过新浪微博数据进行验证,排序实验与覆盖率实验结果验证了该模型用户影响力度量的准确性与有效性。     

基于多维特征分析的社交网络意见领袖挖掘

在社交网络中进行意见领袖的挖掘对信息传播与演化的深度分析、舆情监控和引导具有重要意义,本文综合结构特征、行为特征和用户的情感特征对意见领袖节点挖掘问题进行研究.本文首先对微博真实文本数据进行话题识别得到主题社区,在主题社区中基于用户节点之间的关注关系构建交互网络拓扑.然后分别从结构、行为和情感三个维度对用户的影响力进行度量.最后,分析用户在主题社区中的影响力分布与传播规律,提出意见领袖识别算法MFP(Multi-Feature PageRank).实验表明,该算法可有效地挖掘潜在的意见领袖节点,能够获得较高的支持率.     

Resolution Enhancement Technology:Integrated Process Solutions using OPC

DUV lithography, using the 248 nm wavelength, is a viable manufacturing option for devices with features at 130 nm and less. Given the low kl value of the lithography, integrated process development is a necessary method for achieving acceptable process latitude. The application of assist features for rule based OPC requires the simultaneous optimization of the mask, illumination optics and the resist.Described in this paper are the details involved in optimizing each of these aspects for line and space imaging.A reference pitch is first chosen to determine how the optics will be set. The ideal sigma setting is determined by a simple geometrically derived expression. The inner and outer machine settings are determined, in turn,with the simulation of a figure of merit. The maximum value of the response surface of this FOM occurs at the optimal sigma settings. Experimental confirmation of this is shown in the paper.Assist features are used to modify the aerial image of the more isolated images on the mask. The effect that the diffraction of the scattering bars (SBs) has on the image intensity distribution is explained. Rules for determining the size and placement of SBs are also given.Resist is optimized for use with off-axis illumination and assist features. A general explanation of the material' s effect is discussed along with the affect on the through-pitch bias. The paper culminates with the showing of the lithographic results from the fully optimized system.     

Cost-effective test solutions for smart card and other integrated flash applications

From its emergence in the late 1980s as a lower cost alternative to early EEPROM technologies, flash memory has evolved to higher densities and speedsand rapidly growing acceptance in mobile applications.In the process, flash memory devices have placed increased test requirements on manufacturers. Today, as flash device test grows in importance in China, manufacturers face growing pressure for reduced cost-oftest, increased throughput and greater return on investment for test equipment. At the same time, the move to integrated flash packages for contactless smart card applications adds a significant further challenge to manufacturers seeking rapid, low-cost test.     

Theoretical analysis of the relationship between the Brillouin gain coefficient and the strain in the optical-fiber sensors

The relation between the power of the Brillouin signal and the strain is one of the bases of the distributed fiber sensors of temperature and strain. The coefficient of the Bfillouin gain can be changed by the temperature and the strain that will affect the power of the Brillouin scattering. The relation between the change of the Brillouin gain coefficient and the strain is thought to be linear by many researchers. However, it is not always linear based on the theoretical analysis and numerical simulation. Therefore, errors will be caused if the relation between the change of the Brillouin gain coefficient and the strain is regarded as to be linear approximately for measuring the temperature and the strain. For this reason, the influence of the parameters on the Brillouin gain coefficient is proposed through theoretical analysis and numerical simulation.     

An improved parallel thinning algorithm with two subiterations

The parallel thinning algorithm with two subiterations is improved in this paper. By analyzing the notions of connected components and passes, a conclusion is drawn that the number of passes and the number of eight-connected components are equal. Then the expression of the number of eight-connected components is obtained which replaces the old one in the algorithm. And a reserving condition is proposed by experiments, which alleviates the excess deletion where a diagonal line and a beeline intersect. The experimental results demonstrate that the thinned curve is almost located in the middle of the original curve connectivelv with single pixel width and the processing speed is high.     

Novel fiber-optical interferometer with miniaturized probe for in-hole measurements

Today, micro-system technology and the development of new MEMS （Micro-Electro-Mechanical Systems） are emerging rapidly. In order for this development to become a success in the long run, measurement systems have to ensure product quality. Most often, MEMS have to be tested by means of functionality or destructive tests. One reason for this is that there are no suitable systems or sensing probes available which can be used for the measurement of quasi inaccessible features like small holes or cavities. We present a measurement system that could be used for these kinds of measurements. The system combines a fiber optical, miniaturized sensing probe with low-coherence interferometry, so that absolute distance measurements with nanometer accuracy are possible.     

Study of waveguide coupling efficiency in hybrid silicon lasers

This paper presents a new method to increase the waveguide coupling efficiency in hybrid silicon lasers. We find that the propagation constant of the InGaAsP emitting layer can be equal to that of the Si resonant layer through improving the design size of the InP waveguide. The coupling power achieves 42% of the total power in the hybrid lasers when the thickness of the bonding layer is 100 nm. Our result is very close to 50% of the total power reported by Intel when the thickness of the thin bonding layer is less than 5 nm. Therefore, our invariable coupling power technique is simpler than Intel＇s.     

Teleportation of an arbitrary unknown N-qubit entangled state under the controlling of M controllers

A new quantum protocol to teleport an arbitrary unknown N-qubit entangled state from a sender to a fixed receiver under M controllers(M < N) is proposed. The quantum resources required are M non-maximally entangled Greenberger-Home-Zeilinger (GHZ) state and N-M non-maximally entangled Einstein-Podolsky-Rosen (EPR) pairs. The sender performs N generalized Bell-state measurements on the 2N particles. Controllers take M single-particle measurement along x-axis, and the receiver needs to introduce one auxiliary two-level particle to extract quantum information probabilistically with the fidelity unit if controllers cooperate with it.     

Diode-end-pumped Nd:YVO4/LBO lasers with 4.2W continuous-wave output at 457 nm

A continuous-wave (CW) 457 nm blue laser operating at the power of 4.2 W is demonstrated by using a fiber coupled laser diode module pumped Nd: YVO4 and using LBO as the intra-cavity SHG crystal With the optimization of laser cavity and crystal parameters, the laser operates at a very high efficiency. When the pumping power is about 31 W, the output at 457nm reaches 4.2 W, and the optical to optical conversion efficiency is about 13.5% accordingly. The stability of the out putpower is better than 1.2% for 8 h continuously working.     

A rigorous proof of MIMO channel capacity’s increase with antenna number

It is well known that adding more antennas at the transmitter or at the receiver may offer larger channel capacity in the multiple-input multiple-output（MIMO） communication systems. In this letter, a simple proof is presented for the fact that the channel capacity increases with an increase in the number of receiving antennas. The proof is based on the famous capacity formula of Foschini and Gans with matrix theory.     

Call for Papers

正Wireless Body-area Networks The last decade has witnessed the convergence of three giant worlds:electronics,computer science and telecommunications.The next decade should follow this convergence in most of our activities with the generalization of sensor networks.In particular with the progress in medicine,people live longer and the aging of population will push the development of wireless personal networks