基于合约事务的工程项目费用管理

为使工程项目费用管理和控制的软件与先进费用管理思想和经验一致,提出了基于合约事务的工程项目费用管理的设计思路和结构体系,解释了所设计的二维费用结构矩阵方法,并在此基础上开发了相应的变更费用管理、费用控制与分析等组件,实现了一个以合约事务为基础的新型项目费用管理系统。实践证明,该设计理论与系统可实现项目费用管理与合约管理的紧密结合,使工程项目费用的控制、分析可有效实行国际先进管理模式,提高了工程项目的管理水平。     

快速园区网拓扑发现方法

基于简单网管协议的拓扑发现通常需要扫描整个网段,尤其是对于小规模园区网,网段中会有许多IP地址无回应,大大增加了拓扑发现时间. 为此,提出用层次遍历的方法由边缘设备向核心设备逐步搜索以便完成拓扑发现,不需要扫描网络中的IP 地址,仅通过地址转发表就能高效快速地获取整个园区网的拓扑结构. 仿真实验表明,该方法可在1 min 内推断出包含80 个节点的网络拓扑关系,通过实际部署进一步验证了方法的有效性.     

基于邻域熵的决策表约简

针对传统粗糙集理论难以处理数值型数据的特点,提出基于邻域熵的决策表特征约简方法.该方法通过引入邻域关系进行信息粒化,定义邻域熵概念,用来度量数值型数据的不确定性,证明邻域熵的单调性原理,提出基于邻域熵与分类精度加权的特征重要度概念,基于邻域熵单调性原理设计了两种启发式特征约简算法.理论分析与实例表明该方法是有效可行的.     

Breeding double low super hybrids with dominant genic male sterility three lines in Brassica napus

A double low homozygous two-type sterile line ZY-2AB, its near-isogenic temporary maintainer line ZY-4, and the full sterile line ZY-3 derived from the cross of ZY-2A with ZY-4, were developed to breed three-line dominant GMS hybrid in Brassica napus. Three years data showed that the ratios of sterile and fertile plants fit the expected 1 ： 1 ratio in ZY-2AB, and the 1：0 ratio in ZY-3, respectively. Some double low super hybrid combinations were screened out when the full sterile line ZY-3 was used as female parent, among which the combination 01Z24 increased 36.88 percent more yield than control and the conbination 98Z131 has been passed through the Sichuan Provincial Regional Test and registered in Sichuan Province. Two years data showed that the agronomic performance of the two-line hybrids derived from crosses of ZY-2A with restorer lines versus that of the three-line hybrids produced by ZY-3 was not different for any of the nine most important agronomic characteristics, revealing that near-isogenic line of homozygous two-type line was used as temporary maintainer could effectively avoid the disadvantage of threeway cross hybrid in breeding three-line dominant GMS hybrid.     

软土地基盾构隧道地震动力响应振动台模型试验研究

历次发生的大震表明,软土地基会增大地震作用的破坏程度。以某软土地区地铁盾构隧道为原型进行振动台模型试验,重点分析隧道结构的动力响应特性及隧道与围岩的相互动力作用。试验分析表明:地震波在土体中的传播特性因隧道结构的存在而发生了改变,隧道的存在对其周围土体和地表的加速度峰值有一定的减小作用。隧道结构应变值在距离拱顶和拱底圆心角为±30°处相对于其他部位较大,这些部位易发生破坏。因此,在隧道结构设计中应适当提高这些部位的抗震措施。     

直拍横打型打法与直拍单面攻型打法的技战术研究——以28届奥运会乒乓球男单决赛为例

直拍横打主要解决直拍打法反手位相持能力弱,反手进攻能力差的缺点.王皓是直拍横打的代表人物,在第28届奥运会乒乓球男单决赛中,王皓输给了同为直拍单面攻代表人物柳承敏.文章对王皓直拍横打型打法与柳承敏直拍单面攻型打法的技战术特点进行了系统分析与研究,探索直拍横打在比赛中的合理运用,对直拍横打的技战术特点进行了探讨,为进—步提高我国直拍横打的技战术水平提供参考.     

控制发送策略对IPsec的补充和完善

针对IPsec无法解决的安全隐患提出了一种新的网络安全协议——有限制发送协议,在新的协议中,如果主机向网络发送大量的具有攻击性的数据包时,其发送权利将会受到限制,从而保证网络的安全.采用OPNET仿真软件对新的协议进行了仿真,仿真结果表明,采用新的协议时,网络性能要好.以目标客户机平均HTTP响应时间为例,采用新的协议时,平均HTTP响应时间为0.013 s,不采用新的协议时,平均HTTP响应时间为0.032 s.     

Scaled down model design of shaking table test of Taizhou Bridge

Taizhou Bridge is the first kilometer level three-pylon two-span suspension bridge in the world and the structural complexity has significant effects on the seismic performance of the bridge. Shaking table test of Taizhou Bridge is arranged to investigate the effects of non-uniform ground motion input, collision between main and side spans and optimal seismic structural system. It’s very important and difficult to design and manufacture the scaled down model of Taizhou Bridge used during the shaking table test. The key point is that the girder and pylons are very hard to be manufactured if the similarity ratio is strictly followed. Based on the finite element method (FEM) analysis, a simplified scaled down model is designed and the bending stiffness of the girder and pylon are strictly simulated, and the torsion stiffness and axial stiffness are not strictly simulated. The inner forces and displacements of critical sections, points of simplified model and theoretical model are compared by FEM analysis, and it’s found out that the difference between the seismic responses is relatively small. So, the simplified model can be used to conduct the shaking table test by the FEM verification.     

基于二维表的对象存储元数据管理

大多数存储系统采用Hash算法或目录子树分区算法来实现元数据在元数据集群内的存储,但是上述算法在元数据修改、删除等操作时系统开销较大,严重影响了系统的性能。文章通过引入二维表存储元数据信息,提出了一种新的存储策略。该策略通过使用二维表、数据库存储过程和特定的递归算法实现了元数据存储。实验结果证明该策略具有良好的存储性能。