有限域上素数阶的安全椭圆曲线的选取及实现*

在有限域上讨论了素数阶的安全椭圆曲线的选取算法,并通过对多项式使用预处理技术和伪随机方法实现了选取算法,实验结果表明在不影响安全性的基础上,该算法比常用的随机算法的速度要快,且实验的结果可用于公钥密码体制中,具有一定的实用价值。     

Experimental and simulation studies on the performance of standing wave thermoacoustic prime mover for pulse tube refrigerator

The thermoacoustic prime mover (TAPM) has gained considerable attention as a pressure wave generator to drive pulse tube refrigerator (PTR) due to no moving parts, reasonable efficiency, use of environmental friendly working fluids etc. To drive PTCs, lower frequencies (f) with larger pressure amplitudes (ΔP) are essential, which are affected by geometric and operating parameters of TAPM as well as working fluids. For driving PTRs, a twin standing wave TAPM is built and studied by using different working fluids such as helium, argon, nitrogen and their binary mixtures. Simulation results of DeltaEc are compared with experimental data wherever possible. DeltaEc predicts slightly increased resonance frequencies, but gives larger ΔP and lower temperature difference ΔT across stack. High mass number working fluid leads to lower frequency with larger ΔP, but higher ΔT. Studies indicate that the binary gas mixture of right composition with lower ΔT can be arrived at to drive TAPM of given geometry.     

基于Multigen的无人机任务飞行仿真系统

介绍基于Multigen仿真软件Multigen Creator, Creator Terrain Studio和Vega Prime的无人机任务飞行仿真系统,在Vega Prime中建立无人机的飞行控制运动函数,实现无人机模型在虚拟仿真场景中的六自由度运动。基于.NET 2003环境下多线程编程技术和SBS网络数据传输,实现该系统的实时应用。仿真结果表明该系统能较好地模拟无人机作战飞行任务。     

基于Vega Prime的虚拟现实车辆智能运动模拟

基于虚拟车辆坐标和车辆运动状态对比实现了车辆运动控制方法,通过研究车辆自由行驶、跟驰和变道实现了车辆的虚拟车辆相应的运动策略,利用Vega Prime相关碰撞检测机制,实现了车辆信号控制,并在Vega Prime平台上使用VC++编程实现了虚拟车辆的智能运动模拟,最后采用北京五道口区域交通流实际算例验证了模拟方法的有效性.研究结果表明:通过对Vega Prime进行二次开发,可以实现高沉浸感、高人机交互的虚拟车辆智能运动模拟,模拟仿真结果与交通实际情况相符.     

虚拟三维场景信息管理系统的交互功能的实现

虚拟现实是一种可以创建和体验虚拟世界的计算机系统,它利用计算机技术生成一个逼真的,具有视、听、触等多种感知的虚拟环境,用户通过使用各种交互设备,同虚拟环境中的实体相互作用,使之产生身临其境感觉的交互式视景仿真和信息交流,是一种先进的数字化人机接口技术.虚拟现实技     

柯召 孙琦—单尊定理的拓广

柯老和孙琦教授在[1]中提出了一个猜想:任意2n-1(n≥1)个有理整数中必有n个整数之和能为n整除。本文目的是将这一猜想推广到任一代数数域的代数整数范围中去。     

基于Vega Prime的环境特效与爆炸特效实现技术

为了提高仿真的逼真程度,本文介绍了Vega Prime采用粒子系统来模拟环境特效,Vega Prime提供了简单易用的编辑粒子系统特效的图形化用户模块,即Lynx Prime。根据该模块重点研究特定粒子系统的生成、属性及运动模型上。并在Vega Prime基础上阐述了爆炸特效的实现技术。     

一种改进的RSA加密算法设计与实现

针对RSA加密算法的加密速度进行了研究,在大数模幂、模乘和平方等运算上作了改进,提高了RSA加密算法的执行效率.最后在模拟环境中对该改进算法进行了测试.     

The Zariski topology on the spectrum of prime <Emphasis Type="Italic">L</Emphasis>-submodules

Let R be a commutative ring with identity and let M be an R-module. We topologize L − Spec(M), the collection of all prime L-submodules of M, analogous to that for FSpec(R), the spectrum of fuzzy prime ideals of R, and investigate the properties of this topological space. In particular, we will study the relationship between L − Spec(M) and L − Spec(R/Ann(M)) and obtain some results.     

A distance measure for large graphs based on prime graphs

Graphs are universal modeling tools. They are used to represent objects and their relationships in almost all domains: they are used to represent DNA, images, videos, social networks, XML documents, etc. When objects are represented by graphs, the problem of their comparison is a problem of comparing graphs. Comparing objects is a key task in our daily life. It is the core of a search engine, the backbone of a mining tool, etc. Nowadays, comparing objects faces the challenge of the large amount of data that this task must deal with. Moreover, when graphs are used to model these objects, it is known that graph comparison is very complex and computationally hard especially for large graphs. So, research on simplifying graph comparison gainedan interest and several solutions are proposed. In this paper, we explore and evaluate a new solution for the comparison of large graphs. Our approach relies on a compact encoding of graphs called prime graphs. Prime graphs are smaller and simpler than the original ones but they retain the structure and properties of the encoded graphs. We propose to approximate the similarity between two graphs by comparing the corresponding prime graphs. Simulations results show that this approach is effective for large graphs.