新型智能材料在力/触觉反馈中的应用

新型智能材料电/磁流变液在电/磁场作用下,能够在几毫秒时间内由牛顿流体状态变为半固体状态.在简单介绍电/磁流变效应产生机理、特点的基础上,阐述了国内外几种典型的基于电/磁流变液体的力/触觉反馈设备的原理、结构和应用,比较了电/磁流变液的优缺点,总结了基于电/磁流变液设备的优势和存在的问题,展望了应用前景.     

CS与BS混合软件体系结构及其在数字化教学系统中的应用

本文对C/S、B/S两种软件体系结构进行了分析比较,论述了其在软件开发中的优势和劣势,认为C/S、B/S混合体系结构更适用于大型复杂系统的开发.最后,通过对其在数字化教学系统中的应用,进一步剖析了C/S、B/S混合体系结构的特点,及其在特定领域中的开发模式.     

基于Java的排队系统仿真研究

在概述排队系统的基础上，分析了常见排队系统的数学特性，构建了新的事件驱动的仿真算法，应用Java对M/M/c，M/M/c/N， G/G/c/∞/K，G/G/c/N/K等排队系统进行仿真。最后对仿真结果进行了评估，发现基于Java用新算法仿真排队系统有速度快、精度高、应用面广等优点。     

变精度覆盖粗糙集

介绍了Ziarko变精度粗糙集模型和覆盖粗糙集模型;定义了多数包含关系;借助引入的误差参数β（0≤β<0.5）,给出了基于对象邻域的变精度覆盖粗糙集模型中β上近似、β下近似、β边界和β负域的定义以及β近似质量和β粗糙性测度定义;详细讨论了β上、下近似算子的性质、集合的相对可辨别性、该模型与Ziarko变精度粗糙集模型和覆盖粗糙集模型的关系;最后探讨了变精度覆盖粗糙集模型中的约简问题并在所给模型的基础上举例说明了它们在信息处理中的应用。     

基于NUT/OS的PPPoE拨号器实现

介绍了在实时操作系统NUT/OS基础上实现PPPoE拨号功能。根据运行于Atmel ATmeg128/10 3CPU上实时操作系统NUT/OS在8位CPU上支持TCP/IP协议的特点,通过对NUT/OS及PPP、PPPoE协议的分析,实现了NUT/ OS还未实现的PPPoE协议,拓展了实时操作系统NUT/OS的适用性。     

基于信息技术的燃料电池电源变换技术研究

电源变换技术是DC/DC、DC/AC、AC/AC、AC/DC的总称。当前的DSP技术,广泛应用于DC/DCDC/AC变换模块,已经解决了很多原来不能解决的客观问题,产生了积极的效应。本文结合燃料电池课题,阐述了信息技术在电源变换技术中的应用,对基于DSP的船舶用双向DC/DC变换器进行了深入分析,为燃料电池技术应用于船舶用电力推进提供了理论依据。     

基于C/S和B/S体系结构应用系统的开发方法

论述了C/S、B/S相结合的管理信息系统开发的方法和步骤,并对其相关理论如:VB访问数据库的方法及接口、在SQL Server中基于C/S数据完整性约束的实现技术、基于B/S体系结构开发应用系统、ASP技术等进行了详细分析与研究;同时,以开发C/S、B/S相结合的学生信息系统为实例.     

C/S和B/S在舰船技术保障中的应用研究

分析了两层、三层客户端/服务器(C/S)和三层浏览器/服务器(B/S)3种信息系统体系结构,在此基础上提出了一种基于三层C/S、B/S混合模式的舰船技术保障信息系统体系结构模型,并对该结构模型及其特点进行了分析和总结。该结构克服了两层C/S、三层C/S和三层B/S体系结构的不足,以便更好地发挥C/S和B/S体系结构的特性和优势。     

P-集合与系统状态预测-识别

在P-集合(X^F,X^F)的基础上,给出了系统状态规律曲线生成模型,得到了系统的P-规律曲线(p^F(x),p^F(x))与系统状态偏离预测定理、系统状态不可分辨定理;并给出了表示系统偏离标准状态程度的量—P-偏离度(PDD^F,PDD^F)、系统状态预测模型及应用。     

粗糙Vague集（值）间k步相似度量新方法

对粗糙集、Vague集及粗糙Vague集的概念、知识表示方法进行了讨论,描述了粗糙Vague集的相关概念,在研究了粗糙Vague集相似性度量方法的基础上,提出了一种对踌躇度п_v（x）k步细化的k步相似度量新方法,并且研究了该方法的相关性质。进一步对k步相似度量在k趋向无穷时求极限,得出粗糙Vague集退化为模糊集的特例情况。     

基于Agent的客户机/服务器模型的设计与实现

在对Agent技术、多Agent技术以及Client/Agent/Server（客户机/代理/服务器）模式的理论分析基础上,指出了传统C/S结构的不足,提出了基于Agent的两层Agent/Server模式.然后基于该模式,给出了一个Agent/Server框架,简称ASFtame.由于引入了先进的FIPA标准和多Agent开发思想,ASFrame能充分发挥移动Agent的移动性,从而提高了应用系统的伸缩性和智能性.     

在基于CORBA/XML网络管理中IDL和XML数据的信息交互*

CORBA与XML结合的关键在于IDL格式和XML格式数据的交互。提出了一种基于WBEM体系结构的网络管理系统的客户端/服务器端模型,同时基于该客户端/服务器端模型提出了一种IDL和XML数据交互的方法并进行了实验实现,实验证明该方法可行。     

NOx sensing properties of In2O3 nanoparticles prepared by metal organic chemical vapor deposition

In₂O₃ nanoparticles were deposited by low-temperature metal organic chemical vapor deposition. The response of 10-nm thick In₂O₃ particle containing layers to NO_x and O₂ gases is investigated. The lowest detectable NO_x concentration is 200 ppb and the sensor performance is strongly dependent on the gas partial pressure as well as on the operating temperature. The sensor response towards 200 ppm of NO_x is found to be above 10⁴. Furthermore, the cross-sensitivity against O₂ is very low, demonstrating that the In₂O₃ nanoparticles are very suitable for the selective NO_x detection.     

Maximal intersection of spherical polygons by an arc with applications to 4-axis machining

Many geometric optimization problems in CAD/CAM can be reduced to a maximal intersection problem on the sphere: given a set of N simple spherical polygons on the unit sphere and a real number constant L≤2π, find an arc of length L on the unit sphere that intersects as many spherical polygons as possible. Past results can only solve this maximization problem for two very restricted special cases: the arc must be either a great circle or a semi-great circle. In this paper, a simple and deterministic algorithm based on domain partitioning is presented for solving this maximal arc intersection problem in the general case when the number L is arbitrary. The algorithm is made possible by reducing the domain of the arcs to a continuous sub-space in R² and then establishing a quotient space partitioning in this sub-space based on a congruence relation. The number of the constituting congruent sub-regions in this quotient space partitioning is shown to have an upper-bound O(E³), where E is the total number of edges on the polygons. The proposed algorithm has a worst-case upper bound O(ME) on its running time, where M is an output-sensitive number and is bounded by O(E³). Examples including two realistic tests for 4-axis NC machining are presented.     

基于QNX实时系统的网络传输性能测试

介绍QNX实时操作系统的特性和系统的微内核结构,进一步阐述了Qnet协议和TCP/IP协议,在此基础上,进行TCP/IP协议和Qnet协议下的网络编程,成功实现两种协议下网络性能测试,实验证明QNX系统下,Qnet协议网络传输性能要优于TCP/IP协议.     

基于模型的机组组合两阶段启发式算法

针对同时考虑机组爬坡速率约束和系统安全约束的机组组合问题,提出一个基于模型的两阶段启发式算法.第1阶段确定可行的机组启停状态,首先构造初始启停状态,并根据模型检验初始启停状态是否可行,如果不可行,则通过目标函数的线性近似和约束松弛构造问题的松弛模型,并将其用于可行化机组的启停状态;第2阶段利用经济分配模型确定机组的输出功率.基于118-母线电力系统的测试验证了所提出算法的有效性和鲁棒性.     

基于余弦代价函数T/4分数间隔盲均衡算法—Simulink仿真

在对T/4-FSE-CMA算法研究分析的基础上,针对非常模QAM信号,提出了一种基于余弦代价函数T/4分数间隔盲均衡算法（T/4-FSE-CCF）。该算法将CMA的代价函数用构造的余弦代价函数来替代;新算法摆脱了CMA对统计模值[R]的依赖,且均衡器理想均衡时该算法的的稳态均方误差（Mean Square Error,MSE）为零。通过MAT-LAB的[M]文件对T/4-FSE-CCF的性能进行验证,在获得算法最佳性能时的参数值后,进一步由这些参数搭建了T/4-FSE-CCF的Simulink仿真模型。     

An improved parallel Jacobi method for diagonalizing a symmetric matrix

We compare five implementations of the Jacobi method for diagonalizing a symmetric matrix. Two of these, the classical Jacobi and sequential sweep Jacobi, have been used on sequential processors. The third method, the parallel sweep Jacobi, has been proposed as the method of choice for parallel processors. The fourth and fifth methods are believed to be new. They are similar to the parallel sweep method but use different schemes for selecting the rotations.

The classical Jacobi method is known to take O(n⁴) time to diagonalize a matrix of order n. We find that the parallel sweep Jacobi run on one processor is about as fast as the sequential sweep Jacobi. Both of these methods take O(n³ log₂n) time. One of our new methods also takes O(n³ log₂n) time, but the other one takes only O(n³) time. The choice among the methods for parallel processors depends on the degree of parallelism possible in the hardware. The time required to diagonalize a matrix on a variety of architectures is modeled.

Unfortunately for proponents of the Jacobi method, we find that the sequential QR method is always faster than the Jacobi method. The QR method is faster even for matrices that are nearly diagonal. If we perform the reduction to tridiagonal form in parallel, the QR method will be faster even on highly parallel systems.     

基于μC/OS-II的μC/IP协议栈在ARM系统中的实现

深入分析了μC/IP协议栈,阐述了其移植原理和实现方案,并给出了在具体软硬件平台上的移植实例。首先,通过分析μC/IP协议栈,结合实时内核μC/OS-II与32位ARM7Core的软硬件平台,论述了μC/IP协议栈的移植原理。然后,根据TCP/IP各层协议的具体实现提出了μC/IP协议栈移植与裁减的一种可行方案。最后,在基于μC/OS-II与ARM7Core的软硬件平台上实现了μC/IP协议栈的移植。实验结果表明:移植后的协议栈实现了网络的基本功能,且运行稳定。开源μC/IP协议栈的移植实现,为基于μC/OS-II的Internet嵌入式系统应用提供一个小型可裁减的TCP/IP协议中间件。     

DP-UserPro: differentially private user profile construction and publication

User profiles are widely used in the age of big data. However, generating and releasing user profiles may cause serious privacy leakage, since a large number of personal data are collected and analyzed. In this paper, we propose a differentially private user profile construction method DP-UserPro, which is composed of DP-CLIQUE and privately top-k tags selection. DP-CLIQUE is a differentially private high dimensional data cluster algorithm based on CLIQUE. The multidimensional tag space is divided into cells, Laplace noises are added into the count value of each cell. Based on the breadthfirst-search, the largest connected dense cells are clustered into a cluster. Then a privately top-k tags selection approach is proposed based on the score function of each tag, to select the most important k tags which can represent the characteristics of the cluster. Privacy and utility of DP-UserPro are theoretically analyzed and experimentally evaluated in the last. Comparison experiments are carried out with Tag Suppression algorithm on two real datasets, to measure the False Negative Rate (FNR) and precision. The results show that DP-UserPro outperforms Tag Suppression by 62.5% in the best case and 14.25% in the worst case on FNR, and DP-UserPro is about 21.1% better on precision than that of Tag Suppression, in average.