内容计费模型探讨

在分析现有计费模式不足的基础上,描述了内容计费的产生、需求及发展,介绍相关标准,并给出一般性的内容计费模型,对其中关键的采集点问题提出自己的看法,为内容计费的深入展开作铺垫。     

基于Parlay API的面向3G内容计费的研究

介绍了第三代移动通信网络中的业务开发技术-Parlay以及开放式接口API，详细分析了该技术的计费业务提供机制．在分析现有计费模式的不足的基础上，描述了内容计费的产生、需求及发展，介绍相关标准．重点研究了ParlayAPI规范中计费SCF（Service Capability Feature）在内容计费的3G计费平台中所提供的计费能力．针对WAP网页浏览业务，使用UML设计了基于流量的计费业务，给出了数据流分析示意图和计费流程．     

内容计费及其网络性能测试

丰富多彩的数据服务为移动运营商创造更多收入的同时,也满足了用户对网络服务的个性需求。如何对这些数据服务进行合理计费也是一个非常重要的问题。传统上,运营商根据用户使用网络的时间或者流量来进行计费。这两种计费方式虽然简单易行,但容易使用户有很多疑惑。为了提供更个性化,更能体现使用网络的价值,基于内容计费（CBB）被认为是更好的计费模式。思博伦通信王海生所撰《内容计费及其网络性能测试》一文首先介绍了基于内容计费模型,然后对引入内容计费带来的问题进行了讨论,最后详细介绍了内容计费的网络性能测试,并提出了思博伦网络性能测试系统——Landslide。本文思路清晰,信息丰富,可供相关业内人士参考。     

移动分组域计费的架构与解决方案

首先分析了现行的分组域计费架构及后续发展,然后介绍了按内容计费和流计费的实现方式,最后给出了中兴通讯在分组域计费方面的综合解决方案。     

移动网中基于内容计费的智能计费解决方案

从内容计费的市场价值和相关标准从无到有的变化说明内容计费的重要性，并通过目前业界的解决方案和厂家实现案例说明内容计费的发展情况。     

移动网的智能计费解决方案——基于内容计费功能

基于内容计费功能是指电信运营商可通过对用户的上下行数据包进行包过滤和分析,以识别区分用户上下行数据传送的内容种类,并把相关的信息传送到运营商的预付和后付费计费系统,令运营商可以通过这些内容计费信息对用户做出更灵活的计费处理。本文详细介绍了基于内容计费功能在3GPP标准中的定义及其相关机制和能力。     

省级移动通信网计费系统案例

移动通信网的计费管理是网络管理的重要组成部分，计费技术比较复杂。以辽宁省移动通信计费网为例，介绍了移动通信网计费系统的实现方法、组网方案及网络拓扑，并介绍了辽宁省移动通信计费网配备华为公司的Quidway系列路由器的情况。     

一种新型计费系统建设方案的探讨

本文简要地介绍了现有计费方案,从实时计费的需求出发,说明了在线计费的必要性.然后结合目前计费系统的实际情况,提出了弹性计费系统的建设方案,并分析了该方案的优势.最后,指出弹性计费系统是一种优化的计费系统.     

CDMA 1X分组域内容计费实现方案探讨

随着数据业务的快速发展,业务种类越来越丰富。文章基于对CDMA 1X分组网现状及3GPP2计费方式的介绍,详细描述了内容计费的优势和实现方式,提出了现网实现内容计费的改造方案及实施要点。     

CDMA 1分组域内容计费实现方案探讨

随着数据业务的快速发展,业务种类越来越丰富。文章基于对CDMA1X分组网现状7A3GPP2计费方式的介绍,详细描述了内容计费的优势和实现方式,提出了现网实现内容计费的改造方案及实施要点。     

EHV transmission in the U.S.S.R. power grid

In 1965, 507 billion kWh of electricity was produced in the Soviet Union, and the total generating capacity of its power stations reached 114 000 MW. The total length of transmission lines, with voltages of 35 kV and higher, ran to 312 000 km. The capacity of the European power interconnections of the U.S.S.R. exceeded 68 000 MW in March 1966. The control of the power industry is centralized under the Ministry of Power and Electrificiation of the U.S.S.R. Ninety-four percent of its electric energy is generated at power stations that are part of interconnected systems. Thermal stations predominate; their generating capacity accounts for 77 percent of the total installed generation. Hydroelectric plants represent 22 percent of the total capacity and 18 percent of the total output. About one percent of the total power production is from nuclear plants. Thirty-six percent of the thermal plants are equipped to transmit heat energy as well as electric power.     

大视场宽谱段星敏感器光学系统设计

星敏感器是一种姿态测量系统,用于测量飞行器的实时姿态。该系统是一种基于CCD 探测器的适用于星敏感器的光学系统。通过相关参数的计算,利用ZEMAX 平台实现了具有良好成像质量的光学系统结构设计。该系统焦距为50 mm,F 数为1.8,具有较大的视场角:2=23,光谱范围较宽:500~850 nm,中心波长为680 nm。捕获三颗导航星的概率达100%。满足星敏感器对弥散斑、能量集中度和畸变等特殊要求。倍率色差得到了很好的校正,仅为0.087 m。系统仅使用6 片球面透镜,结构简单紧凑,易于加工制造。     

Calculations of systems unreliability by algebraic manipulation of failure event

Computations of reliability of a given system is an important field of research in reliability engineering. There are many techniques available in the literature. Some of these are based on Boolean algebra's relations. In these papers unions of events have been reduced to give the reliability of a system. Reduction of union of events involve a lot of work and give rise to a large number of terms.In this paper we have adopted a different approach. We first set up some simple algebraic lemmas on intersections and give their proofs. Next we represent the system failure event as the intersection of paths failure events. By applying our lemmas on this intersection of events step by step we are able to expand the system failure event in the form of unions of mutually exclusive events. Simple substitution of probabilities of success or failure, as the case may be, of the events involved in the union of expanded form gives the unreliability of the system.The algorithm is explained by an example.     

Statistical characteristics of chaoticity and incomplete chaoticity of irregular oscillations generated by a strongly nonlinear autonomous system with two degrees of freedom

The notion of the interval of nonergodicity as one of the statistical characteristics for time realizations of an irregular process is introduced. A method for determination of this factor based from the analysis of autocorrelation functions of truncated realizations is developed. The chaoticity of irregular oscillations in a strongly nonlinear autonomous system with two degrees of freedom is proved using the criterion of decomposition of time correlations. The statistical indication of the existence of incomplete chaoticity of oscillations in the case of incomplete decomposition of correlations is formulated. Conditions of weak distortions of the energy spectrum for truncated realizations are determined. Probability distribution functions for the characteristics of an irregular time process in the studied system are considered.     

基于Simulink的PD雷达地杂波的仿真

计算机技术的发展使雷达系统仿真得到广泛应用。环境杂波的仿真在雷达仿真中占有极其重要地位。介绍了PD（脉冲多普勒）雷达地杂波的频谱分布特性,讨论了网格叠加法计算地杂波的原理,给出了杂波散射系数模型,分析了杂波幅度起伏特性和频谱特性,给出了单元杂波信号的叠加方法。最后,建立了视频地杂波仿真模型,并绘出了三维功率谱。     

缝隙阵列天线DOA估计的互耦影响与修正

互耦的存在严重影响了DOA估计的精度，文中研究了存在互耦情况下的DOA估计问题，重点讨论了阵列单元互耦效应的有效计算和对MUSIC算法的修正问题；以缝隙阵列天线为例，通过对无限阵散射参量的修正得到有限阵的散射矩阵和阻抗矩阵，进而通过阻抗矩阵估计互耦的影响，并对MUSIC算法进行修正，最后给出了仿真结果。     

Excitation of luminescence in porous silicon with adsorbed ozone molecules

A new effect of the excitation of luminescence in porous silicon during adsorption of ozone from the gaseous phase was investigated. The signals of ozone-induced luminescence and photoluminescence decay with time of ozone exposure in a strictly correlated way; simultaneously, an oxide-phase growth is observed in porous silicon. A linear relationship was found between the luminescence intensity and the amount of oxide phase formed in the presence of ozone. Correlated shifts in the spectra of ozone-induced luminescence and photoluminescence are observed if the porosity of silicon varies. A mechanism for this effect is proposed. According to this mechanism, in the case of the dissociative adsorption of ozone, the exothermic reaction of oxidation of backbonds of a silicon atom takes place on the surface of nanocrystallites. Energy released is spent for the excitation of electron spectrum of silicon crystallites. The radiative relaxation in the case of ozone excitation proceeds similarly to that of the photon excitation of luminescence in porous silicon.     

Visx20/20B准分子激光治疗系统激光腔状态与治疗效果的关系分析

目的 分析Visx20/20B准分子激光系统激光腔状态与治疗效果的关系，探讨最佳激光腔状态，同时提出改进激光腔状态的方法，以获取手术最佳疗效。方法观察手术过程中激光腔的各种状态和术后病人的治疗效果，将激光腔各种状态与病人疗效进行对比，做出定性分析。在以后的工作中，随时根据激光腔状态来调整我们的治疗方案，从而力争达到病人的最佳治疗效果。结果 激光腔状态包括气体、激光腔本身清洁度、CV值、前后镜等几部分，对病人疗效影响较大。结论 准分子激光手术中，Visx20/20B型准分子激光系统激光腔各部分的状态与手术疗效有很大关系，必须随时关注激光腔状态，以保证手术最佳疗效。     

Optimization and Performance Analysis of Zero Forcing Decision Feedback Detector for MIMO Block-Fading Channels with Per-Antenna Power Control

In multiple-input multiple-output (MIMO) antenna systems, the zero forcing decision feedback detector (ZF-DFD) is used to recover transmit signals. In this paper, we propose a per-antenna power control (PAPC) scheme based on ZF-DFD for MIMO block-fading channels. The optimal power controlled ZF-DFD can minimize the block error rate (BLER) and maximize the lower bound of the channel’s free distance at high signal-to-noise ratio (SNR) region subject to a power constraint. Additionally, the optimal power controlled ZF-DFD can achieve this BLER performance without any ordering operation at the receiver. The performance analysis among the conventional ZF-DFD without feedback, the optimal power controlled ZF-DFD with power feedback, and the ZF-DFD with full channel state information feedback shows that the optimal ZF-DFD achieves a tradeoff between performance and feedback overhead. We compare the bit error rate (BER) and BLER performance of the optimal ZF-DFD with other detectors without power feedback by simulation. In simulations, the execution times required by these detectors are also reported to compare their complexity. It comes straight that the optimal power controlled ZF-DFD proposed in this paper can achieve good performance with small feedback overhead and have low complexity. Kun Zhao was born in Hefei, China, on 9 October 1979. He received his BS and MS degrees from University of Science and Technology of China (USTC), in 2001 and 2003, all in Electrical Engineering. He is now a Ph.D. candidate at USTC.His research interests are in the area of spread spectrum and CDMA communications, radio resource management in mobile communications, space-time signal processing and multiuser MIMO. Ling Qiu received her BS degree from Southeast University, P. R. China, in 1990. She also received MS and Ph.D. degrees from University of Science and Technology of China (USTC), in 1997 and 1999, all in Electrical Engineering.From 1990 to 1994, she was an engineer in the Institute of Nanjing Electronic Technology. In 1999, she joined the Department of Electronic and Engineering and Information Science, USTC as a lecturer. Since 2002, she has been an Associate Professor. She is a coauthor of two books and over 40 conference/journal papers. Her research interests are in the area of wireless communications, spread spectrum and CDMA communications, wireless access networks and protocols, radio resource management in mobile communications, space-time signal processing and multiuser MIMO. Jinkang Zhu is a professor of Department of Electronic Engineering & Information Science of University of Science and Technology of China (USTC). Now he is director of Personal Communication Network and Spread Spectrum Lab. of USTC, Chair of the Academic Committee of School of Information Science & Technology of USTC, Vice-Chiar of the Academic Committee of USTC.He was Permanent V-President of School of Information Science & Technology of USTC, Chairman of PCN Experts Group of Communication Project of National R & D on High-Technology Programme of China, Member of Information Technology Expert Group of the Chinese Academy of Sciences, Member (Representation of China Mainland) of Technical Forum on Wireless Communications of Asia Pacific Region, Member of Technical Advisory Committee of IEEE VTC'99 Fall, Member of Technical Program Committee of IEEE VTC'2000, Member of Technical Program Committee of SCI'2001.His research area is Wireless and Mobile Communications, CDMA and Spread Spectrum Communications, Signal Process of Communications, and Wireless Networks. He got two awards of Ministry of Science & Technology of China, three awards of Chinese Academy of Science. He published five books and 100 papers, where synchronous CDMA method proposed is used in TD-SCDMA Standard of 3G as basic technology.     

利用Rugate膜系理论实现宽角度入射1500-1600nm波段减反射薄膜的研究

阐述了利用Rugate膜系理论设计宽角度减反射薄膜的方法,从理论上分析了在宽角度的情况下,偏振产生透过率不同的原因,模拟设计了光谱区在1500-1600nm波段,入射角从0度到80度宽角度减反射薄膜,探索出了一条新型膜系设计的途径,其优化结果是较为理想的．这一研究方法如能在太阳能、光纤通信、航天、激光等领域应用,将大大地提高光能的利用率,具有重要的应用价值．