The Research and Implementation of Load Scheduling Algorithm and Resource Management Model Based on CG Tree

本文研究在CG树模型下的负载调度算法和资源管理模型，以实现分布式集群系统的负载均衡和资源合理利用。通过研究现有的负载调度算法，本文提出了一种基于CG树模型的请求式动态负载调度算法，该调度算法根据集群系统内各个节点所拥有的资源信息和负载情况，结合外界请求的来源和请求内容，动态地选择集群系统内最合适的一个节点来为外界请求服务。该算法能在满足外界请求的同时，有效的实现集群系统的负载均衡。我们提出了一种基于CG树的请求式资源管理模型。该模型能在适当的时候对集群系统中访问次数较多的文件资源进行扩散，使得更多的服务器节点拥有这个资源，以避免系统负载失衡；同时，在适当的时候对外界访问次数很少的资源副本进行删...The Paper studies the load scheduling algorithm and resource management model in CG tree in order to reach load balance and make rational use of resources in distributed server cluster. Through studying existing load scheduling algorithm, we propose a requested dynamic load scheduling algorithm based on the CG tree, which works mainly according to the resource information and load state of nodes i...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_计算机软件与理论学号：2005130231

LVS集群系统模型及其任务分配算法的研究

对Linux虚拟服务器集群的结构和原理进行了分析和描述,包括LVS的框架,负载均衡技术,并对LVS中的8种任务分配算法进行了分析,最后提出了对任务分配算法的一种改进思想

Synthesis optimization,characterization and electrochemical performance of Li[Li_(0.2)Mn_(0.54)Ni_(0.13)Co_(0.13)]O_2 as cathode material of lithium ion battery

采用共沉淀法合成锂离子电池用富锂正极材料lI[lI0.2Mn0.54nI0.13CO0.13]O2。通过X射线衍射光谱法(Xrd)、扫描电子显微镜法(SEM)和电池充放电测试方法来考察高温烧结时间和烧结温度对所合成材料的结构和性能的影响。结果表明:900℃烧结15 H合成的样品材料具有较好的层状结构和较优越的综合电化学性能;在1.0 C充放电时,首次放电比容量高达181.6 MAH/g(2.0~4.6 V),充放电效率为68.2%,80圈循环后的放电比容量为176.5 MAH/g,具有较高的容量保持率(97.2%);同时,该富锂正极材料表现出较好的倍率性能,在3.0 C充放电时还有148.8 MAH/g的放电比容量。The conditions of sintering time and sintering temperature were optimized to prepare the cathode material Li [Li0.2Mn0.54Ni0.13Co0.13]O2 with co-precipitation method.The prepared materials were characterized and tested by means of XRD,SEM and electrochemical measurements.It is found that the material synthesized by sintering at 900 ℃ for 15 h exhibits the best electrochemical performance,including high initial discharge capacity & coulombic efficiency and good cycling stability in the first 80 charge/discharge cycles at 1.0 C rate in comparison with materials synthesized under other conditions.Meanwhile,the material synthesized at the optimized condition also shows good rate capability,delivering high specific discharge capacity of 148.8 mAh/g at 3.0 C.深港创新圈合作项目(SG200810200106A

基于VRRP的LVS高可用性研究

本文介绍了VRRP(虚拟路由器冗余协议),并描述一种基于VRRP的解决方案。该方案可用于LVS解决其单点故障问题,提高LVS的高可用性

MnO/Nitrogen-doped graphene composite cathode for high performance lithium oxygen batteries

本文采用水热法制备了MnO/氮掺杂石墨烯复合材料. 作为非水锂空气电池的正极催化剂, 该复合材料表现出了优异的电化学性能以及循环稳定性.; 在充放电电流密度为0.05 mA cm~(-2)时, 其能量效率高达84.6%, 远高于目前文献所报道的非贵金属催化剂的能量效率,; 也超过了基于贵金属的催化剂. 其氧还原反应(ORR)和氧析出反应(OER)的过电势分别仅为0.11和0.41 V.; 扫描电子显微镜(SEM)和透射电子显微镜(TEM)结果表明, 所制备的MnO纳米颗粒能够均匀地分散在氮掺杂石墨烯的表面.; 密度泛函理论(DFT)计算揭示, MnO(100)面是主要的催化活性面, 其理论ORR和OER的过电势分别仅为0.21与0.24 V,; 充放电电势差为0.45 V, 与实验结果0.52 V相当.MnO/nitrogen-doped graphene (MnO/NG) composite cathode was fabricated by; a facile one-pot method as cathode catalyst for non-aqueous lithium; oxygen batteries. It exhibited superior electrochemical performance with; higher round-trip efficiency and better cyclic stability. It showed a; high round-trip efficiency of 84.6% at the current density of 0.05 mA; cm~(-2) with the discharge and charge overpotentials of 0.11 and 0.41 V,; respectively. Through scanning electron microscopy, transmission; electron microscopy and X-ray photoelectron spectroscopy, it was; confirmed that MnO nanoparticles were homogeneously dispersed on NG; surface. The density functional theory calculations demonstrated that; the superior electrochemical performance of MnO/NG might be attribute to; the exposure of stoichiometric MnO (100) surface, with the ORR and OER; overpotential only to be 0.21 and 0.24 V, respectively. The; discharging-charging voltage gap is 0.45 V, in good agreement with the; experimental value of 0.52 V.国家重点基础研究发展计划; 国家自然科学基金; 国家基础科学人才培养基

锂/钠离子电池材料的固体核磁共振谱研究进展

深入全面理解锂/钠离子电池材料的静态结构及演化过程是提升电池材料性能的关键因素,在材料结构的各种表征方法中,固体核磁共振波谱(SS NMR)技术是获取电池材料局域结构以及微观离子扩散动力学等定量信息的一个重要表征手段。到目前为止,人们通过SS NMR技术在获取与分析电池电极/电解质材料的离子占位,充放电过程中材料的结构演化以及微观离子扩散动力学过程如离子传输路径与离子扩散系数等信息上已取得重要的研究进展,进而为理解分析电极材料的储锂机制,电池材料的构效关系乃至电池的衰减机理等方面提供了重要实验数据。结合课题组的研究工作,综述了近三年来SS NMR技术在锂/钠离子电池电极和固体电解质材料研究以及核磁共振成像技术在电池领域的应用研究进展

Controlling Reversible Expansion of Li2O2 Formation and Decomposition by Modifying Electrolyte in Li-O2 Batteries

锂空电池分别使用空气中的氧气和金属锂作为正负极活性材料，具有极高的能量密度。但是，这一体系尚不能实现商业化的应用，其中一些关键问题未能解决。由于其正极活性材料是气体，使得电化学反应涉及气-液-固三相界面，电极过程十分复杂。与其它二次电池相比，空气电极需要考虑结构因素和催化因素。不仅要改善氧气电化学反应的动力学迟缓问题，还要考虑放电产物的驻留空间问题。董全峰教授课题组在前期开展了基于空气电极固相表面电催化研究，并结合电极结构方面的问题，构筑了有利于氧气发生反应的仿生开放式结构电极。 该研究工作主要由化学化工学院2015级iChEM直博生林晓东（第一作者）在董全峰教授、郑明森副教授和龚磊副教授的共同指导下完成，理论计算由袁汝明助理教授（共同第一作者）完成，曹勇、丁晓兵、蔡森荣、韩博闻等学生参与了部分工作。周志有教授和洪宇浩博士生在电化学微分质谱方面给予大力的帮助与支持。【Abstract】The aprotic lithium-oxygen (Li-O2) battery has attracted worldwide attention because of its ultrahigh theoretical energy density. However, its practical application is critically hindered by cathode passivation, large polarization, and severe parasitic reactions. Here, we demonstrate an originally designed Ru(Ⅱ) polypyridyl complex (RuPC) though which the reversible expansion of Li2O2 formation and decomposition can be achieved in Li-O2 batteries. Experimental and theoretical results revealed that the RuPC can not only expand the formation of Li2O2 in electrolyte but also suppress the reactivity of LiO2 intermediate during discharge, thus alleviating the cathode passivation and parasitic reactions significantly. In addition, an initial delithiation pathway can be achieved when charging in turn; thus, the Li2O2 products can be decomposed reversibly with a low overpotential. Consequently, the RuPC-catalyzed Li-O2 batteries exhibited a high discharge capacity, a low charge overpotential, and an ultralong cycle life. This work provides an alternative way of designing the soluble organic catalysts for metal-O2 batteries.This work was supported by the National 973 Program (2015CB251102), the Key Project of National Natural Science Foundation of China (21673196, 21621091, 21703186, 21773192),and the Fundamental Research Funds for the Central Universities (20720150042,20720150043). The authors thank Prof. Eric Meggers at Philipps-Univeristaet Marburg for his discussion about the synthesis of RuPC complex; Prof. Gang Fu at Xiamen University for his instructive discussions in DFT calculations; Lajia Yu and Dandan Tao at Xiamen University for their assistance in EPR experiments and UV-Vis spectroscopy experiments, respectively; and Yu Gu and Tao Wang at Xiamen University for their discussions in XPS results and CV data,respectively. 该工作得到科技部重大基础研究计划（项目批准号：2015CB251102）、国家自然科学基金（项目批准号：21673196、21621091、21703186、21773192）和中央高校基本科研业务费专项资金（项目批准号：20720150042、20720150043）的资助。 此外，感谢傅钢教授在理论计算方面的讨论和建议，Eric Meggers教授在配合物合成上的讨论，泉州师范学院吴启辉教授和化学化工学院谷宇博士生在X射线光电子能谱方面的帮助，于腊佳老师在电子顺磁共振实验上的帮助，陶丹丹博士生在紫外可见光谱测试上的帮助以及王韬博士生在循环伏安方面的讨论

ST段抬高型急性心肌梗死院前溶栓治疗中国专家共识

急性心肌梗死仍然严重威胁我国人民健康,在我国广大城乡地区,形势更为严峻[1,2]。及时救治急性心肌梗死患者,降低死亡率和保护心脏功能刻不容缓。鉴于我国的实际情况,院前溶栓治疗在大城市以外的城乡地区具有重要意义。为此,中国医师协会胸痛专业委员会及中国医学救援协会心血管急救分会专门组织有关专家制订了本共识,旨在帮助院前医疗急救人员对急性心肌梗死患者选择最佳

专题:中国非正规经济(下)

李明欢以非正规雇佣为主要内涵的非正规经济之所以能够在跨国领域大行其道,根源之一在于全球化正如同由跨国资本把握方向盘的巨型“压路机“,力图突破一切不利于其扩张之国境边界,朝着政治和

An Entrant of Smaller Fullerene: C-56 Captured by Chlorines and Aligned in Linear Chains

A smaller fullerene C-56 (#913) is stabilized, isolated, and crystallographically characterized as C56Cl10. The geometric parameters of C56Cl10 imply the otherwise unstable cage of C-56 can be stabilized by chlorination through releasing its surface strains and maintaining fragmental aromaticity. An unexpected C Cl center dot center dot center dot Cl C short contact, as well as the linear alignment with pearl - necklace-shaped, is revealed in C56Cl10 crystal.NSFC,20525103,20531050,20721001,20425312, 20423002 973 Program,2007C13815301