15 research outputs found

    Spam Mail Filtering System Based-on Network Processor

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    随着互联网的普及,传统的纸质信件已经逐渐被高效、低成本的电子邮件所取代。然而,随之而来的垃圾邮件问题也日趋严重。基于内容的垃圾邮件过滤方法是国内外研究的热点,支持向量机、贝叶斯、Windows和KNN等是其中较为出色的方法,它们有各自优缺点。基于内容的过滤方法在训练邮件样本以及过滤邮件时往往需要耗费大量的时间。 网络处理器是随着网络带宽不断增大,对数据处理的速度要求越来越高的环境下诞生的。拥有多个处理器,针对网络数据处理的指令集以及多级存储结构等特点,使得网络处理器能够高效、便捷的处理2-7层的网络数据。 本文在网路处理器上实现了支持向量机和贝叶斯这两种基于内容的垃圾邮件过滤系统。主要工作...As the popularization of Internet, the efficient and cheep e-mail has become the substitute to the conventional papery mail. But at the same time, spam mails cause lots of problems. Content-based spam filtering technologies have become the mainstream anti-spam mail methods so far. Support vector machine (SVM), Bayes, windows and KNN are excellent ones of these technologies and they have advantages...学位:工学硕士院系专业:信息科学与技术学院计算机科学系_计算机系统结构学号:2005130229

    Density Functional Calculations on Metallabenznenes

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    金属杂芳香化学是当前金属有机化学的研究热点之一,金属苯作为一类重要的金属杂芳香化合物,其独特的结构和潜在的应用前景受到人们广泛关注。通过系统的密度泛函理论计算,我们研究了几类金属苯的结构及其稳定性,考察了过渡金属改变、金属中心配位环境的变化、芳环上氢原子的取代、芳环上碳原子取代等结构修饰对不同自旋态金属苯相对稳定性的影响。此外,我们对中心金属为Fe、Ru、Os的六配位硅杂金属苯和中心金属为Co、Rh、Ir的五配位硅杂金属苯进行了初步的计算研究,讨论了a位硅杂金属苯的芳香性。获得的主要结果如下: 1.计算表明,影响金属苯单重态与三重态相对稳定性的最大因素是其过渡金属中心的改变,第一过渡系的金属...Metallaaromatics have attracted considerable attention in the organometallic chemistry. Metallabenzenes, as a key type of transition-metal-containing aromatic compounds, exhibit novel structural features and potential applications in chemistry and advanced materials, and many metallabenzenes have been synthesized successfully in the past decades. Herein extensive density functional calculations we...学位:理学硕士院系专业:化学化工学院化学系_物理化学(含化学物理)学号:2052008115171

    Designed and Implementation of Wireless Fax Terminal are Base on WCDMA Technology

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    随着通信市场的日新月异,经济的快速发展,人民生活水平提高,用户已经不仅仅满足于现有固定办公方式,越来越多的商务人群需要移动商务办公。移动商务办公三大元素的其中两个元素:语音通话,无线数据上网功能已经得到基本满足,但传统基于CSD(CircuitSwitchedDomain)方式的G3无线传真业务由于占用宝贵的有限无线的网络资源而使得资源利用率低以及无线网络对无线传真的承载性较差而使各无线运营商一直没有正面积极的推广无线传真业务。无线传真业务作为无线办公的重要组成部分,缺少它就无法达到真正的移动商务办公。为此,本文着重研究基于IP数据包传输方式的WCDMA无线传真设备的硬件与软件的实现方案。 ...With the quickly progress of communication market, the rapid development of economy, the improvement of people's living stytles. The businessmen are not merely content to the office in fixed spot, but also the office of movement. Among the three elements of movement business mode, voice calls, wireless data via internet function are already obtained satisfies basically, but wireless fax service, w...学位:工程硕士院系专业:信息科学与技术学院电子工程系_电子与通信工程学号:X200922200

    分散式角色激活管理中的角色查找

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    【摘 要】: 角色激活是基于角色的访问控制中的重要环节, 用户通过激活系统为他分配的角色子集来执行与角色相对应的权限。目前基于角色访问控制主要特点是用户主动、系统被动, 从而给用户带来记忆各种角色-权限分配情况的负担。本文提出一种分散式的基于查找的角色激活管理方法, 与传统方法不同之处在于它是一种用户为被动、 系统为主动的智能访 问控制, 在对企业环境下的动态约束提供有效支持外, 减轻了在传统角色激活方式下用户需要掌握角色- 权限分配情况的负担。基金项目: 中山市科技项目( 2006A157) ; 厦门大学院士基金(0630- E23011); 厦门大学新世纪优秀人才基金(0000- X07116)

    中国企业“走出去”宏观竞争力分析

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    一、引言世界经济的繁荣与发展离不开经济全球化。近年来,全球经济在以发达国家为主导,跨国公司为主要媒介的发展过程中,通过生产要素在全球范围流动和配置,有效提升了要素使用效率,优化了全球产业布局,形成了高效规范的市场运转模式。在此背景下,中国政府提出\"走出去\"战略,鼓励国内企业加入经济全球化浪潮,参与国际2016年度国家社科基金重大项目“中国国际援助和开发合作体系创新研究”(项目批准号:16ZDA037)的支

    “近墨者黑”:负向情绪会传染吗?——基于“班级”社交网络视角

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    研究他人的负向情绪是否会传染给本人的关键在于:一是社交网络范围的划定;二是界定负向情绪的传染是因果关系,抑或仅是相关关系。本文利用2013—2014学年中国教育追踪调查数据,基于"班级"社...中国人民大学中国调查与数据中心设计与实施的“中国教育追踪调查(CEPS)数据”项目,该调查的项目负责人是中国人民大学的王卫东博士;; 中央高校基本科研业务费专项资金(17wkzd07);; 教育部人文..

    泛在知识环境下的嵌入式知识服务—伊利诺伊大学图书馆学习报告

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    本文以美国伊利诺伊大学图书馆为范例,介绍该校图书馆在泛在知识环境下交流创造知识理念下的学校图书馆自动化与服务系统、嵌入式教学服务、支撑工具服务、Libguides 学科资源导航、学术共享空间等。阐述馆员工作内容与服务范式,包括科研数据管理、资源数字化、数字工具开发、资源发现与管理等方面。通过交流与学习,对于伊利诺伊大学图书馆知识服务范式,学科馆员的角色定位、特征以及学科服务发展趋势进行深入的分析与探讨

    Effects of Serum Medicated with Duhuo Jisheng Decoction on the Induced Degeneration of Articular Chondrocytes in Vitro Culture Based upon “caveolin-p38MAPK” Signal Pathway

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    目的:观察独活寄生汤含药血清对兔退变软骨细胞“CAVEOlIn-P38MAPk“信号通路的调控作用,探讨独活寄生汤治疗骨关节炎的作用机制。方法:将20只3月龄新西兰兔随机分为生理盐水组(空白血清组)和独活寄生汤组(含药血清组),每组10只。分别在24 H、36 H、48 H不同采血时间点采集独活寄生汤含药血清和空白血清,将5%、10%、15%、20%不同浓度两种血清作用于体外培养第2代软骨细胞,确定含药血清最佳干预条件;建立体外退变软骨细胞模型,分别给予独活寄生汤含药血清(含药血清组)和空白血清(空白血清组)干预36 H,收集软骨细胞,运用WESTErn blOT法检测血清干预后退变软骨细胞CAVEOlIn-1、P38、P-P38蛋白表达,rT-PCr法检测血清干预后退变软骨细胞白细胞介素(Il)-1β、肿瘤坏死因子(Tnf)-α、基质金属蛋白酶(MMP)-3、MMP-13、CAVEOlIn-1 M rnA表达。结果:浓度为15%的36 H采血时间点含药血清的促增殖作用最明显;退变软骨细胞中存在“CAVEOlIn-P38MAPk“信号通路的激活,独活寄生汤含药血清可抑制CAVEOlIn-1、P-P38蛋白表达及Il-1β、Tnf-α、MMP-3、MMP-13、CAVEOlIn-1 M rnA的表达,差异有统计学意义(P<0.05)。结论:独活寄生汤能通过抑制“CAVEOlIn-P38MAPk“信号通路的激活及其下游效应分子,从而有效抑制软骨细胞凋亡。Objective:To observe the effects of serum medicated with Duhuo Jisheng Decoction on the induced degeneration of articular chondrocytes in vitro culture based upon "caveolin-p38MAPK" signal pathway and probe the mechanism of Duhuo Jisheng Decoction in the treatment of osteoarthritis.Methods:20 March old New Zealand rabbits were randomly divided into normal saline group(blank serum group)and Duhuo Jisheng Decoction group(drug containing serum group),10 rats in each group.The second generation of cartilage cells was cultured in vitro using different time points of sample collection such as 24 h,36 h and 48 h,serums medicated with 5%,10%,15% and 20% concentrations of Duhuo Jisheng Decoction and blank serums.The best intervention time of medicated serum was determined,which was then used to deal with the degenerating chondrocytes.The degenerated cartilage cell models in vitro were established,which were intervened by the serum medicated with Duhuo Jisheng Decoction(drug containing serum group)and the blank serum(blank serumgroup)after 36 h,collecting chondrocytes.The Western Blot method was used to detect the expression of degenerated cartilage cells caveolin-1 and p-p38 protein after serum intervention.The RT-PCR method was usedto detect the expression of degenerated cartilage cells IL-1β,TNF-α,MMP-3,MMP-13 and caveolin-1 m RNA after serum intervention.Results:The concentration of 15% and 36 h sampling time point serum on the proliferation;the activation of "caveolin-p38MAPK" signaling pathway in the degeneration of cartilage cell,Duhuo Jisheng decoction containing serum can inhibit the expression of caveolin-1,p-p38 protein expression and IL-1β,TNF-α, MMP-3,MMP-13,caveolin-1,m RNA,the difference was statistically significant(P < 0.05).Conclusion:Duhuo Jisheng decoction can inhibit the "caveolin-p38MAPK" signal pathway and its downstream effector molecules, which can effectively inhibit the apoptosis of cartilage cells.国家自然科学基金资助项目(81302986); 福建省卫生厅青年科研课题资助计划项目(2012-2-69); 福建省自然科学基金(2013J01389); 福州市卫生系统科技计划(2013-S-wq6

    沿海产盐区与非产盐区18~45岁人群碘营养状况及甲状腺功能水平研究

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    目的掌握厦门市沿海产盐区与非产盐区居民盐碘、18~45岁人群碘营养和甲状腺功能水平状况,为采取针对性的防治措施提供依据。方法选择沿海产盐区翔安区和非产盐区集美区为调查点,调查居民合格碘盐食用率、18~45岁育龄期妇女和男性尿碘水平、甲状腺激素水平和海带、紫菜的摄入习惯。结果产盐区和非产盐区盐碘中位数均为27.21 mg/kg,合格碘盐食用率分别为95.33%和96.33%;18~45岁男性尿碘中位数分别为206.55μg/L和232.95μg/L,尿碘<100μg/L的比例分别为20.97%和10%;18~45岁育龄期妇女尿碘中位数分别为176.95μg/L和227.70μg/L,尿碘<100μg/L的比例分别为21.67%和25%;产盐区和非产盐区18~45岁男性和育龄期妇女的甲状腺激素TSH、Tg、FT3、FT4、TPOAb、TT3、TT4中位数均在正常值范围内;产盐区18~45岁男性的甲状腺功能亢进阳性率为3.4%、育龄期妇女的甲状腺功能减退和亚临床甲状腺减退症的阳性率均为1.67%,而非产盐区均为0。产盐区和非产盐区18~45岁男性和育龄期妇女中均有一定比例易患甲状腺免疫性疾病的人群。每月食用海带、紫菜的次数≥4次、1~3次和<1次的人尿碘组间比较无统计学差异。结论产盐区和非产盐区18~45岁男性和育龄期妇女碘营养总体处于适宜状态,应坚持食盐加碘措施,对育龄期妇女在婚前体检时开展常规碘营养水平和甲状腺功能检测

    Stabilization of anti-aromatic and strained five-membered rings with a transition metal

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    1981年诺贝尔化学奖获得者、美国康奈尔大学RoaldHoffmann教授评价该项工作说:'The paper is an excellent one--it's quite a mazing that the parent Os system,molecule 1,chooses to give the osmapentalyne'。德国化学家Uwe Rosenthal教授等在同期《自然—化学》杂志的《News and Views》栏目以《Breaking the rules》为题撰文评述了这一研究成果。全文地址:http://www.nature.com/nchem/journal/vaop/ncurrent/pdf/nchem.1702.pdfAnti-aromatic compounds, as well as small cyclic alkynes or carbynes, are particularly challenging synthetic goals. The combination of their destabilizing features hinders attempts to prepare molecules such as pentalyne, an 8π-electron anti-aromatic bicycle with extremely high ring strain. Here we describe the facile synthesis of osmapentalyne derivatives that are thermally viable, despite containing the smallest angles observed so far at a carbyne carbon. The compounds are characterized using X-ray crystallography, and their computed energies and magnetic properties reveal aromatic character. Hence, the incorporation of the osmium centre not only reduces the ring strain of the parent pentalyne, but also converts its Hückel anti-aromaticity into Craig-type Möbius aromaticity in the metallapentalynes. The concept of aromaticity is thus extended to five-membered rings containing a metal–carbon triple bond. Moreover, these metal–aromatic compounds exhibit unusual optical effects such as near-infrared photoluminescence with particularly large Stokes shifts, long lifetimes and aggregation enhancement
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