215 research outputs found

    The Solution of Enterprise-Grade Visual Monitoring On Nagios

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    企业信息系统监控(一般需包含故障报警和性能监测)是目前互联网行业研究热点。在目前全球范围内主流的商用和开源监控软件中,基于Linux环境下的Nagios开源监控软件脱颖而出。凭借着Nagios监控插件的可自定义开发和监控模块的灵活性等优势,Nagios已成为一款不可多得的信息系统监控工具。然而,在现实的互联网企业环境中,如何让Nagios监控软件配置成一款适合企业实际需要的优秀监控平台还需要面临一系列的挑战。 本文本着“工匠精神”,以某互联网企业信息系统的监控项目为背景,针对互联网企业对信息系统本身安全性和高可用性要求的特点,并结合该企业实际监控需求对监控系统进行了整体的规划,主要包括采用面...Enterprise Information system monitoring (including alerting identification and performance monitoring) is in hotspot of current Internet industry. Among today’s worldwide mainstream commercial and open source monitoring software, Nagios open source monitoring software based on Linux is seen outstanding. Due to flexibilities of monitoring modules and customized development of monitoring plug-in, N...学位:工程硕士院系专业:信息科学与技术学院_工程硕士(计算机技术)学号:X201222100

    Research and Implementation of Underwater Acoustic Speech Transmission and Speech Concealed Communication Based on MELP

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    本文在对美国联邦语音编码标准——2.4Kbps混合激励线性预测(MixedExcitationLinearPrediction,MELP)算法进行详细研究的基础上,提出了一种甚低速率的改进型800bpsMELP语音压缩编解码算法,该算法具有三帧联合量化、三帧参数根据清音/浊音的不同组合进行分类量化、以及对语音信号的参数进行矢量量化等诸多特点。 与此同时,本文研究了基于变换域的信息隐藏算法,采用提升小波变换的方法和本文提出的800bpsMELP语音压缩编码算法,完成了“基于提升小波变换的语音隐藏”算法设计,该算法嵌入容量大,适合在可用频带窄的水声信道中应用。 理论仿真及实际水声信道实验证明:...Through the detailed research on the U. S. Federal Standard - Mixed Excitation Linear Prediction (MELP) speech coding algorithm at 2.4Kbps, this thesis presents an improved 800bps MELP algorithm at extremely low rate. In the proposed algorithm, three consecutive frames are jointly quantized, three frames parameters are distinctly quantized according to the different unvoiced/voiced(U/V) frame comb...学位:工学硕士院系专业:信息科学与技术学院通信工程系_通信与信息系统学号:2332008115327

    Anomalous IR Optical Properties of Monodispersed PtNi Nanoparticles

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    采用电位置换反应以及化学还原法制备了单分散PTnI纳米粒子,循环伏安结果显示该纳米粒子在0.1MOl·l-1硫酸介质中对CO的氧化表现出比本体PT电极更好的电催化活性.以CO为探针分子,采用电化学原位红外光谱研究了PTnI纳米粒子上的特殊红外光学性能.结果表明,PTnI纳米粒子无论是在玻碳电极还是在金电极上,均表现出对称的双极谱峰,同时给出很强的增强效应.论文研究结果有助于进一步了解低维纳米材料特殊红外性能的本质.Monodispersed PtNi nanoparticles were synthesized by galvanic displacement reaction and chemical reduction.The monodispersed PtNi nanoparticles demonstrate, by cyclic voltammetry, enhanced electrocatalytic properties for CO oxidation in 0.1 mol·L-1 H2SO4 solution compared with bulk Pt electrode.In situ electrochemical Fourier transform infrared(FTIR) spectroscopy using CO as the probe molecule was studied.The CO adsorbed on either the PtNi/GC(glassy carbon) electrode or PtNi/Au electrode exhibits characteristics of a symmetric bipolar IR feature with a strong enhancement factor.The results of this paper contribute to the understanding of the special properties and origin of the anomalous IR properties of lowdimensional nanomaterials.supportedbytheNationalNaturalScienceFoundationofChina(21229301;21403126); ResearchFoundationofEducationBureauofHubeiProvince;China(D20131302)~

    FABRICATION OF IrO_2-pH MICROELECTRODE AND ITS APPLICATION IN STUDY OF CHEMICAL MICRO-ENVIRONMENT AT STEEL/CONCRETE INTERFACE

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    采用电化学阳极氧化和高温碳酸盐氧化两种方法制备IrO2 - pH微电极 ,其特点是对氢离子响应快、线性范围宽、机械性能好、具有长期稳定性 .考察了该电极的 pH响应特性、化学成分、机械性能等 .结果表明 ,这种IrO2 -pH微电极适用于钢筋 /混凝土界面 pH值的原位测量The corrosion behavior of the reinforcing steel has a close dependence on the chemical micro-environment at the steel/concrete interface.In this paper,a kind of IrO 2-pH microelectrode was prepared by anodic electrochemical oxidation and thermal oxidation in carbonate.In the latter case,IrO 2 electrode showed fast linear response,wide linear range(pH 0~14),satisfying mechanical property and long-term stability.The formation of IrO 2 electrode was characterized and the potential response to H + was tested to explore the optimum condition of fabrication of the IrO 2 electrode.The IrO 2-pH electrode was applied for the in-situ measurement of pH at the steel/concrete interface.国家自然科学基金资助项目 (资助号 :5 98710 43

    聚乙烯吡咯烷酮对模拟混凝土孔隙液中钢筋的缓蚀效应

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    应用电化学阻抗谱和极化曲线测试技术,结合扫描电子显微镜(SEM)、X射线光电子能谱(XPS)和拉曼(Raman)光谱分析,研究了表面活性剂聚乙烯吡咯烷酮(PVP)作为缓蚀剂对钢筋的缓蚀效应和机理.结果表明,PVP对pH值为11.0,含0.5 mol/L NaCl的模拟混凝土孔隙液中的钢筋具有良好的缓蚀作用,可有效抑制钢筋的腐蚀;PVP浓度变化对钢筋腐蚀行为有显著的影响,当浓度为25 mg/L时,PVP对钢筋的缓蚀效率达到89.1%;PVP通过在钢筋表面形成吸附膜来抑制钢筋的腐蚀.国家自然科学基金(批准号:21573182,51671163,21203158,21621091,21173177)资助~

    混凝土中钢筋腐蚀早期过程宏观腐蚀电池与微观腐蚀电池相互作用

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    建立一种阵列电极技术,通过测量不同时空的微电极腐蚀电位、电偶电流及其动态变化,研究了在腐蚀介质作用下,混凝土中钢筋腐蚀发生、发展早期过程阳极区和阴极区分布特征,探讨了钢筋腐蚀过程宏观腐蚀电池与微观腐蚀电池的相互作用机制.结果表明,伴随着点腐蚀的发生、发展过程,在钢筋/混凝土界面宏观腐蚀电池的作用明显,宏观腐蚀电池电流分布与腐蚀电位有密切的对应关系.混凝土中钢筋腐蚀过程总是存在着宏观腐蚀电池和微观腐蚀电池,二者密切相关、相互作用,对钢筋局部腐蚀的发生、发展过程有重要影响.国家自然科学基金重点项目(批准号:50731004);国家科技支撑计划项目(批准号:2007BAB27B04)资

    加快补齐厦门居家养老服务“医、养、助”结合短板的研究

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    前言多年来,在厦门市委、市政府的正确领导和市老龄工作委员会成员单位的共同努力下,厦门市居家养老服务有了长足的发展。但从发展现状或与东部省市进行横向比对看,厦门市居家养老服务\"医、养、助\"结合仍存在明显短板,主要表现在居家社区养老服务能力薄弱、机构养老发展缓慢、医养结合不够紧密等方面,这无疑将影响厦门市养老服务业持续、健康发展。可见,就当前全市形势,单靠政府解决数量众多的老龄人口所需的

    Electrochemical Impedance Spectroscopic Studies of the First Lithiation of Si/C Composite Electrode

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    采用球磨法制备了SI/C复合材料,X射线衍射(Xrd)和扫描电子显微镜(SEM)测试结果显示SI/C复合材料中硅保持着良好的晶体结构且均匀的分散于炭黑基体中.充放电测试结果表明SI/C复合材料首次放电容量高达3393 MAH/g,4周之后可逆容量均保持在1000 MAH/g左右,表现出较好的循环性能.电化学阻抗谱测试结果显示,SI/C复合材料电极在首次嵌锂过程中分别出现了代表接触阻抗、固体电解质相界面界面膜(SEI膜)阻抗、电荷传递阻抗和相变阻抗的圆弧,并详细分析了它们的变化规律.The Si/C composite materials were prepared by ball milling method,and characterized by X-ray diffraction(XRD) and scanning electron microscopy(SEM).The result displayed that Si in the Si/C com-posite materials still maintained a good crystal structure and uniformly dispersed in carbon black matrix.The first discharge capacity was 3393 mAh/g,and 4 cycles later still retained 1000 mAh/g,showing better charge-discharge cycle performance.Electrochemical impedance spectroscopy test indicated that there ap-peared three semicircles respectively representing the impedance of contact problems,solid electrolyte in-terface film(SEI film),charge transfer and phase transformation in the first lithiation,and their evolutive principles were also investigated.中央高校基本科研业务费专项资金(Nos.2010LKHX03;2010QNB04;2010QNB05);中国矿业大学科技攀登计划(No.ON090237);江苏省普通高校研究生科研创新计划(No.CX10B_153Z)资助项

    Analysis on the characteristics of macrobenthis community in the North-west Daya Bay of South China Bay in spring

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    利用2008年春季在大亚湾西北部海域开展的12个测站的大型底栖动物调查资料,对该海域大型底栖动物的群落特征进行分析。结果表明该海域内大型底栖动物优势种由粗帝汶蛤(TIMOClEA SCAbrA)、波纹巴非蛤(PAPHIA undulATA)、上野蜾蠃蜚(COrOPHIuM uEnOI)、方背鳞虫(lEPIdOnOTuS SQuAMATuS)、刀明樱蛤(MOErEllA CulTEr)和角海蛹(OPHElIA ACuMInATA)等6种组成;可划分为4个群落,群落Ⅱ和群落Ⅰ为主体群落,群落Ⅲ和群落Ⅳ分布区较小,群落间差异较大。大型底栖动物数量上以个体较大的软体动物占优,但群落的组成则以多毛类和甲壳类为主,其组成情况基本上反映了群落的特征。群落Ⅰ以多毛类-甲壳类为表征,群落Ⅱ则以甲壳类-多毛类-软体动物为表征。栖息环境的差异,是造成群落间差异的主要原因;群落多样性水平呈群落Ⅲ>群落Ⅱ>群落Ⅰ>群落Ⅳ,沉积环境的污染状况和人为扰动是影响多样性水平的主要因素;群落整体的稳定性较好,未受到明显的扰动,但分布于航道区域和渔业生产作业区的群落Ⅳ和群落Ⅲ,在航道建设、疏浚和渔业生产的影响下,群落受到一定程度的扰动,稳定性较弱。Based on the data collected from 12 research stations in the North-west Daya Bay,South China Sea in spring 2008,the characteristics of macrobenthis community were examined.The results showed that the dominant macrobenthic species were Timoclea scabra,Paphia undulate,Corophium uenoi,Lepidonotus squamatus,Moerella culter and Ophelia acuminate.The macrobenthos community could be divided into four groups with notable differences.Group Ⅰ and Ⅱ were the dominant groups,while the distribution areas of Groups Ⅲ and Ⅳ were relatively small.Overall,molluscs was dominant in quantity in the macrobenthos community but the community was mainly composed of Annelida and Arthropoda,reflecting the characteristics of the community.The dominant macrobenthic species of group Ⅰ were Timoclea scabra,Nephtys oligobranchia,Theora lata,Sigambra hanaokai,Glycinde gurjanvae,Prionospio malmgreni,Timoclea scabra,Turritella bacillum,Corophium tridentium,Phyllodocidae und.,Nectoneanthes alatopalpis,Ericthonius pugnax,Pseudopythina sp.and Stylochus ijimai.Species belonging to this group distributed in the nearshore area of Aotou Harbor and Nanhai Petrochemicals Basement Group Ⅱ assemblage includes Paphia undulata,Timoclea scabra,Corophium uenoi,Prionospio malmgreni,Sigambra hanaokai,Ophelia acuminata,Mediomastus sp.,Nephtys oligobranchia,Moerella culter,Corophium lamellatum,Paraprionospio pinnata and Prionospio pulchra.These species distributed mainly around the Chunzhou Island where suspended long line culture of oyster was common.The discriminating species for Group Ⅰ were S.hanaokai,N.soligobranchia,P.malmgreni,N.alatopalpis and E.pugnax while group Ⅱ were C.uenoi,P.malmgreni,S.hanaokai,N.oligobranchia,T.scabra,M.sp.,Phyllodocidae und.,P.pinnata,O.acuminata,C.lamellatum,M.culter and Chaetozone sp.Group Ⅲ assemblage were mainly found in the west side of Mabianzhou,where it was a fishing ground for Arthropoda in Daya Bay.Group Ⅳ was distributed in area where main shipping routes passed through,in the east side of area of Group Ⅱ and in between the area of Group Ⅰ and Ⅲ.For each community group,while group Ⅱ Group Ⅰ was dominated by Annelida and Arthropoda while Group Ⅱ was dominated by arthropoda,annelida and mollusca;such difference is mainly because of the difference in habitat conditions.Diversity of macrobentho community was highest in Group Ⅲ,followed by Group Ⅱ,Group Ⅰ and then Group Ⅳ.Poor habitat condition caused by pollution,sedimentation and other human disturbances were the main reasons for the differences in diversity between groups.In general,macrobenthos community in the North-west Daya Bay of South China Sea was stable in spring.However,community structure of Groups Ⅳ and Ⅲ,which distributed in the main navigation route and fishing grounds,were less stable;suggesting the disturbances from maintenance of navigation channel and fishing activities might have reduced community stability.中央级公益性科研院所基本科研业务费专项基金(2007ZD08;2007TS08;2010YD10

    Electrochemical Impedance Spectroscopic Studies of the First Lithiation of Si/C Composite Electrode

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    The Si/C composite materials were prepared by ball milling method, and characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The result displayed that Si in the Si/C composite materials still maintained a good crystal structure and uniformly dispersed in carbon black matrix. The first discharge capacity was 3393 mAh/g, and 4 cycles later still retained 1000 mAh/g, showing better charge-discharge cycle performance. Electrochemical impedance spectroscopy test indicated that there appeare three semicircles respectively representing the impedance of contact problems, solid electrolyte interface film (SEI film), charge transfer and phase transformation in the first lithiation, and their evolutive principles were also investigated
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