基于K-最近邻基站的移动手机自组网路由协议

通过分析AODV算法及其存在的问题,结合节点的移动速度和方向等信息, 提出了一种基于K-最近邻基站的移动手机自组网混合路由协议。在新协议中, 当网络的本地基础设施发生故障时,每个本地节点首先生成并维护一个K-最近邻基站信息表,然后基于该K-最近邻基站信息表,利用改进的AODV协议来进行按需路由。理论分析与仿真结果表明, 新算法的性能要优于传统的按需路由协议AODV,因此,更适合移动手机自组网中的路由。     

MANET自组织按需认证模型的研究

构建安全可信的MANET 必须考虑到其自身的特性。目前关于MANET 的安全认证研究大多是利用中心认证服务器为用户颁发证书,较少考虑到MANET 自身的自组织特点,很难完成网络的快速部署。结合MANET 的特性,提出一种自组织按需式认证方案。该方案不需要中心认证服务器,充分利用节点自身功能,在完成身份认证的同时具有良好的伸缩性。     

Impacts of an ATF cladding on neutronic performances of the soluble-boron-free ATOM core

This article is mainly concerned with the impacts of various accident tolerant fuel (ATF) claddings on neutronics performances of a soluble-boron-free (SBF) small modular reactor (SMR) core. There are two ATF cladding concepts which are evaluated here: (a) coating Zircaloy-4 cladding with a thin layer of Cr or Cr alloys; (b) high-strength and oxidation-resistant claddings: stainless steel and FeCrAl. Comparisons between Zircaloy-4 and ATF claddings are done in terms of the cycle length, discharge burnup, pin peaking factor (PPF), burnup reactivity, and spectral change. Moreover, the ATF claddings are also compared in view of the rim effect, neutron absorption by the cladding and He production in the cladding. In addition, a linear reactivity model is used to estimate the required U-235 enrichment so that the cycle length with ATF claddings should be equivalent to that with the reference Zircaloy-4 case. Furthermore, impacts of a selected ATF cladding are then analyzed in a centrally shielded burnable absorber (CSBA)-loaded FA in terms of PPF, burnup reactivity, and spectral change. Based on the CSBA-loaded FA analysis, a minor modification of burnable absorber loading strategy in the SBF autonomous transportable on-demand reactor module core is proposed to adopt the selected ATF cladding without compromising the core performance. The lattice calculations are done using the Monte Carlo Serpent 2 code with the ENDF/B-VII.1 nuclear library, while the 3-D multi-physics core calculations are performed using a Monte Carlo-diffusion hybrid procedure.     

Improved Multicast Protocol Based on Routing Grid

Problems may occur in ad hoc network when packets are being multicast. Global routing structure may also produce extra processing cost because the dynamic topology will introduce frequent exchange of routing vector or routing state between nodes. To deal with these problems an improved multicast protocol based on routing grid is designed to ensure that the multicast packets could be sent to destination through dynamic topology network using multicast routing grid.     

基于多元神经网络融合的分布式资源空间文本分类研究

针对实体产业对科技资源的服务需求,以服务效应作为资源文本分类标准,提出一种基于多元神经网络融合的分布式资源空间文本分类模型。设计了包含词嵌入层、卷积层、双向门控循环单元层、注意力机制层和softmax层的多元神经网络通路;在此基础上采用基于需求—效应—资源分类策略,完成了从定性科技资源需求到定量资源服务效应求解,再到定性科技资源输出的映射变换,重点解决了分布式科技资源局部和全局语义特征形式多样、文本长距离依赖特征显著、重要资源信息难以准确识别的问题,进而从分布式科技资源空间中快速准确地获取效应知识,提升实体产业产品研发效率和创新能力;通过万方专利科技资源数据集验证了所提方法的可行性和有效性,为更加全面地挖掘资源文本特征和按需服务实体产业提供了一种新的思路和手段。     

高校楼宇供暖节能控制系统的研究与应用

针对高等院校供暖的特点及供暖中存在的问题,设计了智能楼宇供暖控制器。该控制器能够根据不同建筑物不同时段的供暖需求,采用智能Bang-Bang调节,通过调节阀门开度,实现按需分时供暖,降低了处于无人状态的建筑物对热能的消耗。同时控制器利用无线GPRS通信与服务器进行数据交互,设计多种保护方案,让建筑供热系统更加安全可靠。实验表明,该控制器节能效果显著,具有良好的社会价值和经济价值。     

分布式变频泵供热系统的控制策略研究

针对分布式变频泵供热系统,提出按照热量控制的方法。该控制方法的特点是:直接采用热量控制,改变了传统用供回水温度来间接控制的方法。针对分布式变频泵供热系统,热源处按照热量总量控制,主循环泵按照压差控制,分布泵按照热量-温差控制的方法。通过该方法可以保证供热质量,并最大限度地保证了供热系统的稳定性,延长了设备的使用寿命。     

移动Ad HOc网络中的公平按需多址接入协议

基于快速、有效竞争预约接入、无冲突轮询传输的思想和带冲突预防的冲突分解策略,本文提出了适于移动Ad Hoc网络的公平按需多址接入(FODA)协议.该协议在分群结构的基础上,利用公平冲突预防算法预约信道资源获得轮询服务,从而完全消除了载波侦听方式下多跳无线网络业务传输中的隐藏终端和暴露终端问题.另外,公平冲突预防算法解决了节点竞争接入时的冲突问题和不公平现象.最后,仿真结果表明,与带冲突避免的载波侦听多址接入(CSMA/CA)和轮询协议相比,FODA协议可以提供较高的信道吞吐量、较低的平均消息丢弃率和平均消息时延.     

A Query Scope Agent for Flood Search Routing Protocols

Flood-search on-demand routing has received considerable interest for its application to mobile ad hoc networks. To alleviate the effects of flooding the network with control packets to discover a route, the concept of an expanding ring search (ERS) has been proposed elsewhere for reducing the packet transmission overhead of the route discovery process. Essentially, ERS consists of incrementally increasing the allowable hop radius of the flood search until a route to the target node is returned. However, ERS incurs additional latency to successfully complete the route discovery procedure. This paper presents a query scope agent (QSA) that assists in the selection of an appropriate ERS. The QSA accepts as input, from the user or network application, a maximum allowable value for route discovery delay. The QSA then estimates network parameter values to determine an ERS approach that satisfies the delay requirement while reducing expected packet transmission overhead. Simulation results show that it successfully achieves this objective. Further, the QSA incurs little communication and computation overhead, and operates in a distributed and asynchronous fashion.     

AVSS:可适应性虚拟存储系统

设计和实现了一种具有适应能力的虚拟存储系统--AVSS,同时提供存储系统容量虚拟化和性能虚拟化管理.AVSS具有如下特征:1)采用扩展的YFQ算法控制带宽资源分配.实现虚拟设备间的性能隔离和性能保证;2)采用分级结构和动态映射机制灵活有效地管理异构存储资源,为资源按需分配提供基础;3)通过数据访问频度统计和应用动态行为分析指导存储布局重组.测试结果表明了设计的正确性,AVSS能够隔离不同应用避免性能干扰,可以按照应用行为调整存储布局,在提高存储系统性能的同时提高了存储资源的利用率.