基于参差距离的相位差变化值的解模糊方法研究

利用相位差及其变化率对辐射源进行定位是新近提出的一种快速单基无源定位方法。本文分析了利用相位干涉议得到的相位差变化值的相位模糊特点,提出了一种利用相位干涉仪的接收天线之间的参差距离对相位差变化值进行解模糊的方法,讨论了正确解模糊的条件和范围,并给出了仿真结果。     

基于SIP协议的IP电话增值业务实现技术

讨论了SIP协议以及基于SIP协议的IP电话增值业务实现技术 ,并对SIPCGI、CPL、SIPServlets、JAINAPIs等几种SIP编程技术进行了分析与比较 ,归纳总结了开发IP电话增值业务的一般方法     

桥丝式电火工品静电发火过程的数值模拟

根据灼热桥丝式电火工品的电热起爆机理，考虑桥丝的轴向和径向散热以及药剂自身的分解放热，建立了灼热桥丝式电火工品静电发火的数理模型。用有限差分法对该模型方程进行求解，得出了桥丝式电火工品的三维温度场分布，并对结果进行了分析。     

Ubiquitous Information Services with JAIN Platform

To provide responsive information services in a ubiquitous computing environment, service software and system development are indispensable. A component-based ubiquitous information system with a JAIN (Java APIs for Integrated Networks) platform to achieve seamless transmissions and reach-everywhere communications was designed in our research. In this development, numerous ubiquitous service modules were identified: location management, roaming, mobile IP and WAP networking. These component-based network modules were constructed using a component composition language with component specification and interface definition, running on top of a distributed service architecture using a JAIN platform to distribute the ubiquitous information services to mobile users. Two applications, Wireless-Application-Protocol (WAP) Mail and Video-on-Demand (VoD) services, show that the JAIN-like platform with the developed networking components effectively fills the gap for application developers between mobile appliances and various kinds of ubiquitous information services.     

奥地利移动通信市场

移动通信市场已经成为奥地利竞争程度较高的市场,主要的4家移动运营商分别是Mobilkom,Max.Mobil,Connect Austria和Tele.ring,其中Mobilkom占有的市场份额最大,奥地利政府于2000年11月拍卖了6张国内3G许可证,除了上述4家运营商获得3G许可证之外,奥地利Hutchison 3G和3G Mobile也得到了3G牌照.     

Bounded Error Schemes for the Wave Equation on Complex Domains

This paper considers the application of the method of boundary penalty terms (SAT) to the numerical solution of the wave equation on complex shapes with Dirichlet boundary conditions. A theory is developed, in a semi-discrete setting, that allows the use of a Cartesian grid on complex geometries, yet maintains the order of accuracy with only a linear temporal error-bound. A numerical example, involving the solution of Maxwell’s equations inside a 2-D circular wave-guide demonstrates the efficacy of this method in comparison to others (e.g., the staggered Yee scheme)—we achieve a decrease of two orders of magnitude in the level of the L₂-error.     

Onr-partition designs in hamming spaces

The concept of the combinatorial matrix of an unrestricted code and the notion of anr-partition design admitted by a code are introduced and discussed in detail. The theory includes a characterization of completely regular codes, and a combinatorial interpretation of the fact that the distinct rows of the distance distribution matrix of a code are linearly independent. In general, it is possible to compute the distance distribution matrix of any code admitting a given partition design by solving a well-defined system of linear equations; this is an efficient technique provided the number of classes in the partition is relatively small.     

Color characteristics of Cu-Zn-Al alloys

ＣＯＬＯＲＣＨＡＲＡＣＴＥＲＩＳＴＩＣＳＯＦＣｕ－Ｚｎ－ＡｌＡＬＬＯＹＳ￣①Ｌｉ，Ｂａｏｍｉａｎ；Ｚｈａｎｇ，Ｘｉｕｈｕａ（ＳｈｅｎｙａｎｇＩｎｓｔｉｔｕｔｅｏｆＧｏｌｄＴｅｃｈｎｏｌｏｇｙ，Ｓｈｅｎｙａｎｇ１１００１５）ＣＯＬＯＲＣＨＡＲＡＣＴＥＲ...     

CDMA位置服务系统的本地定位平台建设

移动位置业务是移动通信网络的一项特色增值业务．将成为今后几年的业务增长亮点之一。中国联通总部的增值业务部于2002年采用集中设置方案，进行了CDMA位置服务系统一期工程的建设。本地定位平台建立于中国联通CDMA位置服务系统基础之上．其功能由以下的一项或多项组合而成：门户功能、中间件功能、GIS系统的的功能和对本地的CP进行管理和计费的功能。