一种可扩展的反馈信任信息聚合算法

针对现有的动态信任聚合算法中利用基于信任链的广播方式进行反馈信任信息搜索而导致的系统运算收敛慢、可扩展性差等问题,建立了直接信任树(DTT)的概念,并基于DTT提出了一种新的可扩展的反馈信任信息聚合算法.根据节点之间的直接信任关系构建DTT,然后利用DTT进行反馈信任信息搜索,同时引入质量因子和距离因子两个参数来自动调节聚合计算的规模.仿真实验表明,算法能够显著提高反馈信任信息聚合计算的收敛性,具有较好的恶意反馈行为检测能力,在恶意节点比率增大时,算法也表现出较强的稳健性.     

基于DDBHMM的LVCSR系统的单步搜索算法

为了在大词汇量连续语音识别(LVCSR)系统中能够利用段长信息,该文按树状组织发音词典,利用语言模型预测技术,基于最大似然状态序列(M LSS)算法,给出了采用基于段长分布的隐含M arkov模型(DDBHMM)的LVCSR系统的二元文法语言模型的单步搜索算法。实验结果表明,尽管单步搜索的替代错误率高于双步搜索,但单步搜索的插入和删除错误率都比双步搜索要低,总体性能上单步搜索要好于双步搜索。同时,DDBHMM能较准确地利用了语音信号中的状态段长信息,采用DDBHMM的LVCSR系统比采用经典的齐次HMM的系统有更好的识别性能。     

基于Agent与个人知识本体的搜索系统研究

传统的信息搜索模型缺乏语义理解。而本体是对共享概念模型的明确的形式化规范说明,提供基于语义的知识表示和共享。本文通过引入个人知识本体,综合利用智能Agent的主动性、协作性、移动性等特性,采用协同式过滤的基本原理,提出了基于Agent与个人知识本体的个人搜索系统,有效地提高了检索效率。文中提出了通过不断的学习用户的反馈信息,对个人知识本体中的概念进行修正的算法,并探讨了多Agent协同信息过滤技术在搜索系统中的应用。     

差分进化算法优化的图注意力网络集成研究

为进一步提升图分类算法的性能和稳健性,提出了差分进化算法优化的图注意力网络集成.首先,通过划分原始样本让不同的基学习器关注数据的不同区域;其次,利用差分进化算法良好的搜索能力,以分类器集成的分类错误率为目标函数优化基学习器的权重向量;最后,在权重向量基础上综合各基学习器的输出作为分类器集成的总体输出.实验引入引文数据集...     

基于领域本体的信息搜索模型

针对目前的搜索模型局限于语法层次上关键词匹配的特点,以领域本体作为知识组织方式,提出了一种语义环境下基于本体的信息搜索模型.在此模型的基础上,分别提出了文档语义标注算法和搜索词语义扩展算法,两种算法分别对文档集语义分析和搜索词语义关系理解,实现双向语义信息搜索的目的.实验结果表明,提出的信息搜索方法能够克服关键词匹配搜索的不足,获得较好的搜索效果     

鉴别局部特征分析及其在人脸识别中的应用

由于传统的鉴别主分量分析(DKL)算法中,主分量分析(PCA)基于全局特征,难以提取人脸的局部特性,该文提出鉴别局部特征分析算法.该算法中,局部特征分析(LFA)代替PCA作为线性鉴别分析(LDA)的前端.一方面,LFA在保留大部分全局信息的同时提取局部特征.另一方面,它为信号提供一种有效的低维表示,增强LDA在小样本问题中的数值稳定和推广性能.文中结合开集模式的人脸认证领域,在PoliceFace、OCRLab人脸库和它们的组合库上对新算法和DKL算法进行实验比较.实验表明,通过结合LFA和LDA,新算法明显降低认证错误率在PoliceFace库上,等错误点错误率降低43.10%;在OCRLab库上错误率降低25.87%;在组合库上错误率降低33.16%.     

一种自适应旅游信息垂直搜索算法的设计与实现

目的针对百度和360等通用搜索引擎搜索旅游信息速度不够快、不准确和分类不明确的缺点,设计和实现了一个面向游客查找旅游信息的网络爬虫,给出了该网络爬虫所采用的自适应垂直搜索算法.方法基于领域本体,建立相应的知识模型和查询模型,并在基于知识模型和查询模型的基础上设计一个综合查询方法,拓展所需要查询的信息.结果设计了一种自适应旅游信息垂直搜索算法和相应的网络爬虫,并用软件实现了该网络爬虫.用设计的网络爬虫对辽宁省公园、辽宁省儿童公园和辽宁省森林公园进行的搜索,采用自适应算法搜索时,Per(用户搜索百分比)为92%,采用基于网页内容的URL选取算法搜索时,Per为82%.对吉林省旅游景点、吉林省公园和吉林省森林公园进行的搜索,采用自适应算法搜索时,Per为91%,采用基于网页内容的URL选取算法搜索时,Per为80%.与经典的搜索方法相比,搜索结果更准确,分类效果更好.结论所设计的垂直搜索算法对旅游信息的搜索是有效的,在查询的准确率和信息的分类上都有一定的提高和改进.     

基于网络资源本体的语义搜索和排位方法

为了正确地理解网络资源概念,精确分析网络信息查询,提出一种基于激活扩散算法的语义搜索方法来提升网络搜索效率。该方法根据网络资源本体中的资源及资源间联系计算其自信息量,然后根据自信息重新扩展了传统的语义搜索和排位方法,从而得到一种新的语义搜索和排位方法。实验结果表明,该方法相比较传统方法,有效的提高了搜索效率。     

SM2签名算法flush-reload cache计时攻击

针对现有flush-reload cache计时攻击中监测地址选取方法不适用于SM2数字签名算法的问题,提出了一种新的监测地址选取方法,通过监测含有函数调用指令的cache块地址,利用函数调用导致的cache块多次访问特性提高了对cache访问行为监测的准确性,降低了恢复标量k的错误率,实现了对SM2数字签名算法的密钥恢复.实验结果表明:所提出的方法能够对SM2数字签名算法实施有效攻击,利用一次签名的旁路信息恢复256 bit标量k的比特错误率仅为1.09%,能在64次密钥搜索的代价下以59%的成功率完全破解签名者私钥.     

基于禁忌搜索的全局记忆增强型优化方法

针对过程系统优化问题中存在多解、而目前通用高性能实时优化算法均为局部算法的情况,提出了基于禁忌搜索的全局记忆增强型优化方法(global mnemonic enhancement optimization,GMEO)。该方法证明了在一定条件下局部最优解是过程系统参数的连续可微函数,并采用禁忌搜索方法以背景计算的方式获得优化计算经验点上的多解信息。基于这些多解信息,GMEO可为优化计算提供全体局部最优解的逼近值。以这些逼近值为初值,可使局部优化算法达到全局优化的效果,并能有效提高过程系统运行的稳健性。基于原油混合问题的数值仿真试验验证了GMEO方法的有效性。在不过多损失实时性的前提下,优化计算的目标函数值得以显著改善。     

Markedness and its Interpretation in Language Use

Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.     

Features of Women's language

Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women＇s language from these perspectives： pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women＇s language, more attention should be paid to language use in social context. What＇s more, the linguistic phenomena in a speaking community can be understood more thoroughly.     

低渗透非均质砂岩油藏启动压力梯度研究

理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。     

On Tragic Consciousness In The Works By Ernest Hemingway

As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.     

Achieving Unusual States of Matter Under High Pressure

正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-     

Exchange-Correlation and Electronic Excitation Energies from Pairing Matrix Fluctuations

We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-     

Density Functional Theory for the Response of Periodic Systems to Electric Fields Based on the Vector Potential Approach

正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that     

On the Thermodynamic Limit for Responses to Static Electromagnetic Fields

For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the     

An affordable accurate evaluation of the binding conformations predicted by molecular docking studies in bio-system

Franck-Condon factors bridge the gap between theoretical modeling and experimental observations for molecular electronic spectroscopy and electron transfer.Under the displaced harmonic oscillator approximation,multidimensional Franck-Condon factors are decomposed into a product of many one-dimensional(1D)Franck-Condon(FC)factors,and each 1D-FC factor is associated with one Huang-Rhys factor that determines the leading contribution of     

Call for Papers

<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with