波浪力计算中的一个新边界元方法

本文就波浪与结构物作用问题，提出了一个新的高阶边界元方法。较之Ｅａｔｏｃｋ Ｔｏｙｌｏｒ和Ｃｈａｕ的方法，本文在体内附助积分方程中应用了满足刚性水面条件和弱刚性底面条件的简单格林函数。计算速度相应地有所提高；漂浮结构的积分方程更为简洁；计算结果与Ｅａｔｏｃｋ Ｔａｙｌｏｒ和Ｃｈａｕ的方法具有几乎相同的精度和收敛速度。     

FD—TD在分析FSS中的应用

本文讨论了用FD TD分析FSS的有关问题,提出了一种适合于在任意入射角情况下分析FSS的有效吸收边界条件,分别以单层、双层FSS为例进行了计算.数值结果和矢量模式法、谱域法的结果非常一致.     

Intermodulation analysis of the collector-up InGaAs/InAlAs/InP HBTusing Volterra series

The intermodulation (IM) distortion of the collector-up InGaAs/InAlAs/InP heterojunction bipolar transistor (HBT) is analyzed using Volterra-series theory. A T-equivalent circuit is used for this analysis. The contribution and interaction of four nonlinear elements: base-emitter resistance, base-emitter capacitance, base-collector capacitance, and common base-current gain are analyzed. For the particular device under investigation, it is found that the cancellation effect is not significant and the base-emitter resistance nonlinearity dominates the third-order IM     

卫星包装箱的随机隔振优化分析

用钢丝绳隔振器将卫星包装箱支承在运输车上,将卫星与车辆简化为二自由度体系,优化分析了在随机路面上行驶时使包装箱响应最小之隔振参数,对实测得到的钢丝绳减振器的非线性迟滞性能作了描述,提出了统计线性化分析的方法。     

Synthesis of Iron-Based Laves Phase Containing Praseodymium Magnetostrictive Materials

The synthesis and magnetostriction of PrxTb1-x.Fe2, PrxTb1-x Fe2BO2 and PrxTb1-x（Fe0.6Co0.4）2 alloys were investigated in this study. The addition of boron or cobalt atom in PrxTb1-xFe2 could effectively prevent the formation of non-cubic phases, and Pr concentration limit was successfully increased from 0.2 to 0.4. X-ray step scanning for the PrxTb1-xFe2BO2 and PrxTb1-x（Fe0.6Co0.4）2 alloys showed that PrFe2 possessed a large spontaneous magnetostriction λ1111.     

三峡三期工程帷幕灌浆施工与工艺管理

介绍了长江三峡三期工程坝基帷幕灌浆按照“自上而下分段、小口径钻孔，孔口封闭，孔内循环”的设计要求进行高压灌浆的施工方法，重点是几个典型工艺管理及其实施效果。     

军械调运方案优化算法的设计与仿真

军械调运问题的数学模型和手工算法过去已有研究,但是当问题较为复杂时,手工算法就要花费大量时间而且准确性也难以保证。针对这一缺陷,本文在已有的数学模型和手工算法的基础上,设计了一种可以用计算机实现的基于递归的算法来寻求军械紧急调运问题的最优方案,并使用面向对象的java语言将算法实现。     

华北盆地南缘大地电磁测深资料地质解释及大别山推覆体成因探讨

根据新近在大别山北麓获得的四条大地电磁测深剖面可以看出,该区地下介质的电性恃征具了明显的纵向上分层、横向上分块的特点。纵向上目上而下分为9个电性层.均有确定的地质属性。其中:第二和第九电性层为本区低阻标志层;第三和第六电性层为相对高阻层;第八电性层为高阻率电阻率高达1000Ω·m以上);第四、第五、第七电性层既有高阻、又有低阻分布.情况比较复杂。■向上的电性分块结构与本区的凸、凹相间的构造格局相对应。这四条大地测深剖面,均反映本区在5～15km深处有一个面积达15000km~2的连续低阻层(第九电性层).电阻率仅有1～3Ω·m。经分析,认为此低阻层可能是一个区域性的主滑脫面,是形成大別山推覆体由北向南的运动面.     

Stochastic analysis of file-swarming systems

File swarming (or file sharing) is one of the most important applications in P2P networks. In this paper, we propose a stochastic framework to analyze a file-swarming system under realistic setting: constraints in upload/download capacity, collaboration among peers and incentive for chunk exchange. We first extend the results in the coupon system [L. Massoulie, M. Vojnovic, Coupon replication systems, in: Proc. ACM SIGMETRICS, Banff, Alberta, Canada, 2005] by providing a tighter performance bound. Then we generalize the coupon system by considering peers with limited upload and download capacity. We illustrate the last-piece problem and show the effectiveness of using forward error-correction (FEC) code and/or multiple requests to improve the performance. Lastly, we propose a framework to analyze an incentive-based file-swarming system. The stochastic framework we propose can serve as a basis for other researchers to analyze and design more advanced features of file-swarming systems.