摘要：Semiconductor technology and packaging is advancing rapidly toward system integration where the packaging is co-designed and co-manufactured along with the wafer ***,materials issues,in particular the mesoscale microstructure,have to date been excluded from the integrated product design cycle of electronic packaging due to the myriad of materials used and the complex nature of the material phenomena that require a multiphysics approach to *** the context of the materials genome initiative,we present an overview of a series of studies that aim to establish the linkages between the material microstructure and its responses by considering the multiple perspectives of the various multiphysics *** microstructure was predicted using thermodynamic calculations,sharp interface kinetic models,phase field,and phase field crystal *** on the predicted mesoscale microstructure,linear elastic mechanical analyses and electromigration simulations on the ultrafine interconnects were *** microstructural index extracted by a method based on singular value decomposition exhibits a monotonous decrease with an increase in the interconnect *** artificial neural network-based fitting revealed a nonlinear relationship between the microstructure index and the average von Mises stress in the ultrafine *** work to address the randomness of microstructure and the resulting scatter in the reliability is discussed in this study.

摘要：A series of WO3 samples with different crystalline phases were prepared by the thermal decomposition method from ammonium tungstate hydrate.X-ray diffraction（XRD）,scanning electron microscopy（SEM）,high-resolution transmission electron microscopy（HRTEM）,X-ray photoelectron spectroscopy,and N2 adsorption-desorption were used to characterize the crystalline phase,morphology,particle size,chemical composition,and surface area of the WO3 *** formation of hexagonal（h-WO3） and monoclinic（m-WO3） crystal structures of WO3 at different temperatures or different times was confirmed by XRD.m-WO3 is formed at 600 ℃,while m-WO3 starts to transform into h-WO3 at 800℃.However,h-WO3,which forms at 800℃,may transform into m-WO3 by increasing the calcination temperature to 1000℃.SEM results indicate that m-WO3 particles exhibit a bulky shape with heavy aggregates,while h-WO3 particles exhibit a rod-like ***,m-WO3 crystals are sporadically patched on the surface of the h-WO3 rod-like particles,resulting in the exposure of both m-WO3 and h-WO3 on the *** is observed that the monoclinic phase（m-WO3）/hexagonal phase（h-WO3） junction was fabricated by tuning the calcination temperature and calcination *** relative ratios between m-WO3 and h-WO3 in the phase junction can readily be tailored by control of the calcination *** photocatalytic activities of WO3 with different crystalline phases were evaluated by the photocatalytic degradation of rhodamine B as a model pollutant.A higher photocatalytic activity was observed in the WO3 sample with the m-WO3/h-WO3junction as compared with the sample with only *** improvement of photocatalytic activity can be attributed to the reduction of the electron-hole recombination rate owing to the formation of the phase junction,whose presence has been confirmed by HRTEM and photoluminescence spectra.

摘要：以常微分方程组的演化建模问题为主要研究对象,设计了分布式异步并行演化算法,并以128台PIII 500微机通过10Mbps的以太网互联而成的机群系统作为模拟实验环境进行了大规模的并行实验,系统地测试了算法中的一些重要的并行控制参数,包括处理机间的连通度、个体的迁移率和迁移代频等对算法性能的影响,得到了一些崭新的实验结果,给出了一些结果分析,特别是对串行算法和并行算法的最好建模结果进行了比较.

摘要：本文研究了一类饱和非有理系统状态反馈镇定问题.通过线性分式表示技术,这类非有理系统可以转化为带有两个非线性回路的线性时不变(linear time-invariant,LTI)系统.假设非有理函数项分别满足局部扇形区间不等式以及局部Lipschitz条件,提出了两种基于LMI条件的镇定方法.最后,举例证明了所提出方法的有效性.

摘要：为满足空间可展开天线大型化、高精度、高刚度发展的迫切需求,提出一种模块化空间可展开天线支撑结构新构型,并对其进行了力学特性研究。首先,基于机构学基本理论,开展了天线总体结构方案设计和结构详细设计,建立了由19个六棱柱模块组成的模块化可展开天线三维模型。其次,根据压杆稳定理论,建立了天线支撑结构静力学分析模型,得到了拉索预紧力的取值范围。再次,建立了天线结构动力学分析模型,进行了模态分析,开展了固有频率影响因素及灵敏度分析与研究。最后,研制了一套天线支撑结构原理样机,并进行了展开功能试验与验证。研究结果表明:预紧拉索对结构刚度的影响较大,配置预紧拉索后结构刚度提高了约2.01倍;固有频率对杆件材料密度和弹性模量、弦杆及斜腹杆尺寸参数较为敏感;研制的原理样机展开平稳、顺畅,验证了结构设计的正确性。研究结果为模块化可展开天线的基础研究及工程应用提供了理论参考和技术支撑。

摘要：设计并实现了一套由热释电传感器和编码的菲涅尔透镜组成的生物特征跟踪识别系统。对传感器得到的生物信号采用了2种方法提取特征:一种是时域方法,即通过AR模型提取自回归系数;另一种是频域方法,即通过主成分分析后的傅里叶变换提取频谱信息。最后采用支持向量机的方法分别验证了2种特征的识别性能。16名受试者在3种行走速度实验环境下的初步结果显示,时域特征的正确识别率为66.48%,而频域特征的识别率则达到了86.5%。上述结果表明了热释电信息用于人体身份识别的潜能,并证明了个体差异与步态频率信息的强相关性。

摘要：先进的无创神经影像技术(如EEG和fMRI)允许研究者直接观察被试在完成多种知觉、运动和认知任务时的大脑活动。将脑功能成像与严密的实验设计和数据分析方法结合起来,我们可以考察大脑不同脑区的功能以及它们之间的交互作用。随着脑功能成像技术在研究人类决策行为中的日益成功运用,一个被称为神经经济学的新兴领域正在逐渐形成和发展起来。本文中首先对脑成像技术进行一个总体介绍,重点在于探讨近年来在多体素分析和多模态数据整合的最新进展。接下来,我们以风险决策、跨时间选择以及社会决策领域的几个研究为例,阐述神经影像技术如何能加深和拓展我们对人类决策的认识。最后,我们讨论了神经经济学中研究中面临的一些挑战以及未来的研究方向。

摘要：水平姿态检测在控制、测量领域发挥着重要作用。实现高精度实时动态检测载体水平姿态既是科技市场的实际需求更是科研工作的挑战,因此设计了高精度动态水平姿态传感器。它主要由微机械倾角传感器、微机械陀螺及其信号处理电路组成,以陀螺来补偿载体行进中带来的各种线加速度干扰,实现移动载体的水平姿态高精度检测。以高精度与实时动态检测为核心,介绍了该系统的总体方案设计,电源转换、敏感信号预处理与模数转换、信号处理及输出的硬件设计和软件处理基本方法,并在设计完成后组装调试。系统测试表明该水平姿态检测系统设计取得预期效果,满足高精度实时动态检测载体水平姿态的设计需求。

摘要：One of the open issues in principle scheme design of mechanical systems is principle representation, which not only outlines the physical principles, but also facilitates the design synthesis. An energy-based approach to represent principle scheme design is proposed. Firstly, an energy interaction model of mechanical systems is established and an intermediate model is derived, in which principle scheme design is transformed into solving the energy functions of system. Then the energy functions are modeled with the language of bond graphs, and principle representation for components is presented. Finally, characteristics of the developed representation approach are analyzed and a design example of gate drive system is given to demonstrate this approach.

摘要：As the most influential representative of New England Transcendentalism, Ralph Waldo Emerson has been commonly known as a man of letters and a prophet of religion. Yet, at the same time, he was also questioned by some scholars who argued that Emerson remained aloof and indifferent to both politics and reforms. Scrutinizing the addresses, essays as well as other published writings of Emerson, we can have a better understanding of his deep thought and wisdom concerning reform, and fully realize his great influence. Based on analyzing two essential aspects of Emerson＇s views on reform, this paper points out that Emerson＇s views on reform are of historical importance; and his views can also provide realistic reference and guidance to the current social reform in china.