产品外形协同设计系统的研究与实现*

提出了协同设计工作模式,给出了系统的工作流程,定义了用户的权限分配,研究了基于交互日志的传输方式,讨论了协同设计过程中的实时更新机制.最后采用了基于MVC的体系结构构建了一个原型系统,该系统在实际应用中,验证了该技术思路的正确性.     

基于电磁感应的矿井探测方法研究及仿真

本文首先分析了矿井探测中遇到的信号干扰种类,结合噪声信号的特点,提出了基于电磁感应的矿井探测方法,给出了其原理图和设计原则.然后详细论述了电磁感应探测方法的具体实现,给出了各主要测试参数的计算公式,明确了在探测过程中需要采集的各种信号.为了验证提出的电磁感应探测方法,最后采用了MATLAB建立了仿真测试模型,并给出了仿真测试结果.     

面向智能电网的云计算技术研究

对面向智能电网的云计算技术进行了研究。首先,引入了云计算的基本概念,分析了它的关键特征。其次,将云计算和智能电网技术进行了融合,提出了智能云的概念。随后,深入研究了智能云的构建、资源管理和安全策略问题。最后,给出了结论和未来的研究工作。     

数据交换在数字化校园中的作用与实现

本文首先概要介绍了数据交换的基础概念和现状,分析了现有的数据交换技术,研究了主要的数据交换机制,对数据映射、工作流技术进行了探讨,重点介绍了数据交换的技术。在理论研究的基础上,设计了一个基于标准XML数据格式和XSLT数据映射格式,结合工作流引擎的数据交换系统模型。该系统模型解决了校园网多个异构系统的数据集成和业务集成的问题,充分考虑了系统的安全性和扩展性,为校同网的信息化建设提供了很好的参考模型。     

发挥多媒体技术的优势,营造轻松的学习氛围

小学语文教学应用于多媒体技术,实现二者的整合,营造了宽松的学习环境,突出了学生的主体地位,激发了学生的创新意识。多媒体技术的应用为小学语文教学改革带来了机遇与挑战,为学生提供了全面的感性材料,活跃了教学气氛,激发了学习欲望。多媒体技术与小学语文教学有机结合,形成了一种全新的学习方式。本文试就发挥多媒体技术的优势,营造轻松的学习氛围进行了阐述。     

智能家居及其发展趋势

介绍了智能家居的发展历程,阐述了智能家居的定义和功能,介绍了其关键技术和嵌入式在智能家居中的应用,预测了其发展趋势,阐明了研究智能家居的重要意义,并指出了智能家居在控制系统、智能建筑系统和计算机领域的广泛运用,将使电子科学和计算机科学等科学中产生革命性的变革.     

基于LabVIEW的光纤惯组自动测试软件的设计与实现

针对传统惯组测试设备测试效率低、可扩展性差的缺点,基于LabVIEW设计开发了光纤惯组自动测试软件.针对软件实现的关键技术进行了研究,主要包括利用插件式的程序架构,设计了低耦合高内聚的测试模块,增强了软件的扩展性和可维护性;设计了详实的配置文件,实现了测试流程的自动化;同时利用多线程和定时循环的软件机制满足了高速数据采集的要求.实际应用证明,该软件提高了测试效率,促进了自动测试设备领域的新发展.     

天下视频Flash 制作下载转换通

宽带流行了,播客兴起了,FLV吃香了,菜鸟也坐不住了,迅即抱回了DV,开通了播客。历经N天修炼,Flash视频终于成为菜鸟的拿手好菜之一。播客的兴起,使得Flash视频(FLV)格式大行其道。究其原因,不外乎FLV视频避免了不安装特定视频插件就     

仿真技术在包装机械研制中的应用

该文阐述了传统的新产品的开发过程和利用计算机仿真技术开发新产品的过程,总结了这两种开发过程的特点,给出了系统仿真的一般步骤.介绍了计算机仿真技术及其在包装机械研制中的两个实际生产的例子,并总结了利用计算机仿真技术开发新产品的特点,它加快了新产品的研制和开发过程,提高了劳动生产率,降低了生产成本,保证了交货日期,提高了产品质量.因此,计算机仿真技术在包装机械研制领域将会得到越来越广泛的应用.     

基于uClinux嵌入式远程环境在线监测系统的开发

该文分析了现有主要环境在线监测系统存在的问题,进行了嵌入式远程环境在线监测系统的总体设计,探讨了基于uClinux的嵌入式环境监测点系统的关键技术,给出了相应的实现过程,提出了基本的解决方案。     

甲苯与异戊二烯合成2,6-二甲基萘的热力学计算

2，6-二甲基萘是合成聚2，6-萘二甲酸乙二酯的重要起始原料。本文讨论了以大宗化工原料甲苯与异戊二烯为起始原料合成2，6-二甲基萘的可能性，并对各种可能化学反应的热力学过程进行了分析，通过分析发现以甲苯与异戊二烯为起始原料经过烷基化、环化及异构化反应可以合成2，6-二甲基萘。同时指出了只有控制异戊二烯合适位置上的碳原子参与烷基化反应才能最终得到目标产物。     

复合型两点多段非均匀性校正算法研究

两点法和两点多段法都是基于定标数据的线性校正方法,前者计算量小但校正精度差;后者虽然可以达到理想的校正精度,却是以计算量的剧增为代价的。针对两点多段法校正精度受分段数控制这一缺陷,改进了传统的两点多段校正算法。使用自动分段在获得满意的校正精度的同时减少计算量和存储空间。进而结合两点法的思路提出复合型两点多段校正算法,分别使用两点法和改进的两点多段法对不同的光敏元进行处理,进一步在保证校正精度的同时提高计算速度。     

A new EP-based α-β-γ-δ filter for target tracking

This study explores a new fourth-order target-tracking α-β-γ-δ filter using an evolutionary programming (EP) for numerical simulation in view that the current third-order α-β-γ filter system tracks only the target's position and velocity but not its acceleration. As demonstrated, the new α-β-γ-δ filter exhibits a significantly improved tracking accuracy over the conventional α-β-γ filter. Not unexpectedly, however, the new α-β-γ-δ filter takes more computation time in the optimization process. To overcome this weakness, an optimal simulation technique via EP is proposed. The developed EP-based α-β-γ-δ filter finds not only the optimal set of filter parameters to minimize position tracking errors but could also reduce the computation time by up to 95% in some time steps. The trajectory simulated by the EP-based α-β-γ-δ filter is compared with those by other filters to illustrate the efficiency of the former filter.     

Hierarchical Matrices Based on a Weak Admissibility Criterion

In preceding papers [8], [11], [12], [6], a class of matrices (-matrices) has been developed which are data-sparse and allow to approximate integral and more general nonlocal operators with almost linear complexity. In the present paper, a weaker admissibility condition is described which leads to a coarser partitioning of the hierarchical -matrix format. A coarser format yields smaller constants in the work and storage estimates and thus leads to a lower complexity of the -matrix arithmetic. On the other hand, it preserves the approximation power which is known in the case of the standard admissibility criterion. Furthermore, the new weak -matrix format allows to analyse the accuracy of the -matrix inversion and multiplication.     

可重构振荡器与双频滤波器的协同设计

实现了一种可重构振荡器与双频率滤波器的协同设计模块。振荡器通过开关二极管的通断来实现频率的可重构,工作频率分别为1.1 GHz和2.0 GHz。与双频滤波器协同设计后,振荡器在两个频率上频偏1 MHz的相位噪声分别从-109.1 dBc/Hz和-112.9 dBc/Hz改善为-125.6 dBc/Hz和-127.9 dBc/Hz,二次谐波抑制分别由协同设计之前的-25 dB和-10 dB改善为-44 dB和-55 dB。     

Isoform-specific expression and characterization of 14-3-3 proteins in human glioma tissues discovered by stable isotope labeling with amino acids in cell culture-based proteomic analysis

Human 14-3-3 proteins have isoform-specific expression and functions in different kinds of normal or tumor cells and tissues. However, the expression profiling of 14-3-3 proteins and isoform-specific biological functions are unclear in human glioma so far. In our study, the expression levels and characterization of 14-3-3 isoforms in human glioma tissues were investigated by a sensitive, accurate stable isotope labeling with amino acids in cell culture-based quantitative proteomic strategy. As a result, except unexpressed 14-3-3σ, the other six isoforms, with different expression levels, were existed in glioma tissues and para-cancerous brain tissues (PBTs). 14-3-3β and η were upregulated, whereas 14-3-3ζ was downregulated in glioma tissues compared with that in PBTs. And the other three isoforms 14-3-3ε, θ, and γ had similar expression levels in human glioma tissues and PBTs. Western blot and immunohistochemistry analysis were both consistent with the quantitative proteomic data. The loss of expression of 14-3-3σ was further discovered due to DNA high methylation in its coding region in glioma by methylation-specific PCR analysis. These results indicated that the four isoforms, including 14-3-3β, η, ζ, and σ, may play important roles in tumorigenesis of human glioma, which is probably used as potential biomarkers for diagnosis and targets for treatment of human gliomas in future.     

无标度网络的最大-最小度搜索算法

许多实际的复杂网络具有无标度的特性,其中高连接度的节点具有重要作用.研究无标度网络的搜索算法.基于最大度的节点的搜索算法只适用于幂律度分布的指数介于2.0和2.3之间的无标度网络.对该算法做出了改进,提出了可适用于较大幂律指数的无标度网络的局部搜索的最大-最小度搜索算法.最大-最小度算法和人们熟知的随机游走、最大度搜索策略相比,更加充分利用了网络节点度分布特性,从而获得了更优的搜索效果,文章从理论分析和仿真结果两方面证实了这一点.     

Adaptive Geometrically Balanced Clustering of <Emphasis Type="Italic">H</Emphasis>-Matrices

In [8], a class of (data-sparse) hierarchical (-) matrices is introduced that can be used to efficiently assemble and store stiffness matrices arising in boundary element applications. In this paper, we develop and analyse modifications in the construction of an -matrix that will allow an efficient application to problems involving adaptive mesh refinement. In particular, we present a new clustering algorithm such that, when an -matrix has to be updated due to some adaptive grid refinement, the majority of the previously assembled matrix entries can be kept whereas only a few new entries resulting from the refinement have to be computed. We provide an efficient implementation of the necessary updates and prove for the resulting -matrix that the storage requirements as well as the complexity of the matrix-vector multiplication are almost linear, i.e., AMS Subject Classifications: 65F05, 65F30, 65N38, 65N50.     

Applications of -Matrix Techniques in Micromagnetics

The variational model by Landau and Lifshitz is frequently used in the simulation of stationary micromagnetic phenomena. We consider the limit case of large and soft magnetic bodies, treating the associated Maxwell equation exactly via an integral operator . In numerical simulations of the resulting minimization problem, difficulties arise due to the imposed side-constraint and the unboundedness of the domain. We introduce a possible discretization by a penalization strategy. Here the computation of is numerically the most challenging issue, as it leads to densely populated matrices. We show how an efficient treatment of both and the corresponding bilinear form can be achieved by application of -matrix techniques.     

雷达寻的制导半实物仿真系统的关键技术研究

首先介绍了雷达寻的制导原理及进行控制系统射频状态半实物仿真的必要性.然后设计一雷达寻的制导半实物仿真系统,介绍了仿真系统的组成.在此基础上着重论证了射频仿真试验条件建设时必须满足的两个关键条件,即射频仿真远场条件及阵列目标的多值特性等关键技术指标.并提出了实际工程建设中对远场条件及阵列多值特性等有关参数的经验选取原则.最后根据某型号射频仿真试验对微波暗室及目标阵列的需求进行了有关设计计算,总结出兼顾工程实施及仿真要求所需的技术指标.为型号研制所需的射频仿真条件建设提供了依据.