UT斯达康小灵通WAP业务简介

WAP协议是开发移动网络上类似互联网应用的一系列规范的组合,是一种用于向无线终端进行智能化信息传递的无需授权、不依赖底层承载技术的协议。WAP业务是针对小屏幕、低速率和内存较小的设备的上网需求而设计的。它可以建立在GSM,CDMA,WCDMA等底层承载技术之上。《UT斯达康小灵通WAP业务简介》一文主要介绍了WAP业务在UT斯达康公司的小灵通系统上的应用情况,包括WAP在小灵通网络上实现的技术原理和WAP业务的产业链结构;并对基于小灵通网络和其它底层网络的WAP服务进行了比较,为感兴趣的读者提供了有益的参考。     

构筑在GPRS之上的VAP应用

WAP规范了一种建立在各种承载之上的应用平台,为移动用户提供了统一,开放的应用接口。在各种承载网络的应用中,构筑在GPRS（通和分组无线业务0之上的WAP是目前最佳的方案。本文从协议和网络结构两个方面对构筑在GPRS之上的WAP进行分析,并就移动终端的接入过程作了讨论。     

WAP——因特网上新生活

无线应用协议（WAP）作为无线因特网的解决方案,目前受到了广泛的关注。本文介绍了WAP的产生背景、应用模型、承载网络、技术解决方案和发展趋。     

无线数据业务用户行为模型研究

对目前无线数据业务中发展较好的WAP业务系统进行了介绍，参考现有的HTTP业务模型对WAP业务模型进行了分析与对比，并运用现网采集的数据作为源数据进行分析得出了WAP业务的业务模型。     

WAP网关的设计与实现

无线应用协议（WAP）作为无线Internet的解决方案,目前受到了广泛的关注。WAP网关是WAP应用模型中的关键功能实体,它是连接客户端与服务器的桥梁。本文分析研究了WAP网关的功能及其在网络中的位置给出了实现WAP网关的设计方案。     

北京GPRS实验系统初探

随着人们对互联网和移动通信业务依赖性的日益加剧,人们迫切希望尽快实现两者的结合——无线互联网业务。通用分组无线业务(GPRS)在原有GSM系统的基础上,采用无线资源的动态分配,有效地利用无线资源,用户最高数据速率提高到171kbit/s。交换网络引入了分组交换的节点,为第二代网络向第三代网络的平滑过渡奠定了基础。本文重点介绍了摩托罗拉公司在北京进行的GPRS实验网的系统配置、功能测试以及基于GPRS平台开展的WAP业务的应用实例。对于运营者系统地了解GPRS系统的业务和功能以及WAP业务有良好的借鉴意义。     

WAP网关的设计与实现

无线应用协议（WAP）作为无线Internet的解决方案,目前受到了广泛的关注。WAP网关是WAP应用模型中的关键功能实体,它是连接客户端与服务器的桥梁。本分析研究了WAP网关的功能及其在网络中的位置,给出了实现WAP网关的方案。     

新一代移动通信综合业务信息服务系统

无线应用协议 (WAP)融合了因特网技术与移动通信技术的优势 ,成为事实上的业界标准。基于WAP技术提供无线信息服务已成为目前移动通信与信息行业新的业务增长点。文章通过对WAP技术及其应用现状的分析 ,提出新一代移动通信综合业务信息服务系统解决方案。该系统将运营商优势与WAP技术充分结合 ,实现符合当前无线应用需求的运营模式和体系结构。     

支持移动多媒体通信中间件的WAP网关

WAP协议是WAP论坛提出的一个开放通信协议;WAP网关进行协议的转换,是移动终端无线接入Internet的枢纽。在简要介绍了无线应用协议后,提出了一个在Linux操作系统平台下运行的WAP网关(数据通信网关)的设计与实现方案,该WAP网关由承载层模块、WAP模块和SMS模块组成,其中详细介绍承载层模块和WAP模块的工作原理,并在实验室环境下对网关进行测试,给出了测试结果。     

无线应用协议（WAP）技术

分析了无线应用协议(WAP)的基本结构、基本功能和协议原理。并就两项较为重要的特殊业务(PUSH业务和WTA业务)的具体实现进行了描述和分析,从而给出了WAP技术的一个全貌。     

Resolution Enhancement Technology:Integrated Process Solutions using OPC

DUV lithography, using the 248 nm wavelength, is a viable manufacturing option for devices with features at 130 nm and less. Given the low kl value of the lithography, integrated process development is a necessary method for achieving acceptable process latitude. The application of assist features for rule based OPC requires the simultaneous optimization of the mask, illumination optics and the resist.Described in this paper are the details involved in optimizing each of these aspects for line and space imaging.A reference pitch is first chosen to determine how the optics will be set. The ideal sigma setting is determined by a simple geometrically derived expression. The inner and outer machine settings are determined, in turn,with the simulation of a figure of merit. The maximum value of the response surface of this FOM occurs at the optimal sigma settings. Experimental confirmation of this is shown in the paper.Assist features are used to modify the aerial image of the more isolated images on the mask. The effect that the diffraction of the scattering bars (SBs) has on the image intensity distribution is explained. Rules for determining the size and placement of SBs are also given.Resist is optimized for use with off-axis illumination and assist features. A general explanation of the material' s effect is discussed along with the affect on the through-pitch bias. The paper culminates with the showing of the lithographic results from the fully optimized system.     

Cost-effective test solutions for smart card and other integrated flash applications

From its emergence in the late 1980s as a lower cost alternative to early EEPROM technologies, flash memory has evolved to higher densities and speedsand rapidly growing acceptance in mobile applications.In the process, flash memory devices have placed increased test requirements on manufacturers. Today, as flash device test grows in importance in China, manufacturers face growing pressure for reduced cost-oftest, increased throughput and greater return on investment for test equipment. At the same time, the move to integrated flash packages for contactless smart card applications adds a significant further challenge to manufacturers seeking rapid, low-cost test.     

An improved parallel thinning algorithm with two subiterations

The parallel thinning algorithm with two subiterations is improved in this paper. By analyzing the notions of connected components and passes, a conclusion is drawn that the number of passes and the number of eight-connected components are equal. Then the expression of the number of eight-connected components is obtained which replaces the old one in the algorithm. And a reserving condition is proposed by experiments, which alleviates the excess deletion where a diagonal line and a beeline intersect. The experimental results demonstrate that the thinned curve is almost located in the middle of the original curve connectivelv with single pixel width and the processing speed is high.     

Theoretical analysis of the relationship between the Brillouin gain coefficient and the strain in the optical-fiber sensors

The relation between the power of the Brillouin signal and the strain is one of the bases of the distributed fiber sensors of temperature and strain. The coefficient of the Bfillouin gain can be changed by the temperature and the strain that will affect the power of the Brillouin scattering. The relation between the change of the Brillouin gain coefficient and the strain is thought to be linear by many researchers. However, it is not always linear based on the theoretical analysis and numerical simulation. Therefore, errors will be caused if the relation between the change of the Brillouin gain coefficient and the strain is regarded as to be linear approximately for measuring the temperature and the strain. For this reason, the influence of the parameters on the Brillouin gain coefficient is proposed through theoretical analysis and numerical simulation.     

Novel fiber-optical interferometer with miniaturized probe for in-hole measurements

Today, micro-system technology and the development of new MEMS （Micro-Electro-Mechanical Systems） are emerging rapidly. In order for this development to become a success in the long run, measurement systems have to ensure product quality. Most often, MEMS have to be tested by means of functionality or destructive tests. One reason for this is that there are no suitable systems or sensing probes available which can be used for the measurement of quasi inaccessible features like small holes or cavities. We present a measurement system that could be used for these kinds of measurements. The system combines a fiber optical, miniaturized sensing probe with low-coherence interferometry, so that absolute distance measurements with nanometer accuracy are possible.     

Development of the readout system for waveguide multilayer optical card

Waveguide multilayer optical card （WMOC） is a novel storage device of three-dimensional optical information. An advanced readout system fitting for the WMOC is introduced in this paper. The hardware mainly consists of the light source for reading, WMOC, motorized stages addressing unit, microscope imaging unit, CCD detecting unit and PC controlling ＆ processing unit. The movement of the precision motorized stage is controlled by the computer through Visual Basic （VB） language in software. A control panel is also designed to get the layer address and the page address through which the position of the motorized stages can be changed. The WMOC readout system is easy to manage and the readout result is directly displayed on computer monitor.     

Study of waveguide coupling efficiency in hybrid silicon lasers

This paper presents a new method to increase the waveguide coupling efficiency in hybrid silicon lasers. We find that the propagation constant of the InGaAsP emitting layer can be equal to that of the Si resonant layer through improving the design size of the InP waveguide. The coupling power achieves 42% of the total power in the hybrid lasers when the thickness of the bonding layer is 100 nm. Our result is very close to 50% of the total power reported by Intel when the thickness of the thin bonding layer is less than 5 nm. Therefore, our invariable coupling power technique is simpler than Intel＇s.     

A method for calculating the center position of collimated light

It is a key problem to accurately calculate beam spots＇ center of measuring the warp by using a collimated laser. A new method, named double geometrical center method （DGCM）, is put forward for the first time. In this method, a plane wave perpendicularly irradiates an aperture stop, and a charge couple device （CCD） is employed to receive the diffraction-beam spots, then the geometrical centers of the fast and the second diffraction-beam spots are calculated respectively, and their mean value is regarded as the center of datum beam. In face of such adverse instances as laser intension distributing defectively, part of the image being saturated, this method can still work well. What＇s more, this method can detect whether an unacceptable error exits in the courses of image receiving, processing and calculating. The experimental results indicate the precision of this method is high.     

Collinear phase-matching study of terahertz-wave generation via difference frequency mixed in GaAs and Inp

The collinearly phase-matching condition of terahertz-wave generation via difference frequency mixed in GaAs and InP is theoretically studied. In collinear phase-matching, the optimum phase-matching wave hands of these two crystals are calculated. The optimum phase-matching wave bands in GaAs and lnP are 0.95-1.38μm and 0.7-0.96μm respectively. The influence of the wavelength choice of the pump wave on the coherent length in THz-wave tuning is also discussed. The influence of the temperature alteration on the phase-matching and the temperature tuning properties in GaAs crystal are calculated and analyzed. It can serve for the following experiments as a theoretical evidence and a reference as well.     

Effects of the alloy compositions on the phonon-polaritons in ternary mixed crystals

Composition dependence of bulk and surface phonon-polaritons in ternary mixed crystals are studied in the framework of the modified random-element-isodisplacement model and the Bom-Huang approximation. The numerical results for Several Ⅱ - Ⅵ and Ⅲ- Ⅴ compound systems are performed, and the polariton frequencies as functions of the compositions for ternary mixed crystals AlxGa1-xAs, GaPxAS1-x, ZnSxSe1-x, GaAsxSb1-x, GaxIn1-xP, and ZnxCd1-xS as examples are given and discussed. The results show that the dependence of the energies of two branches of bulk phonon-polaritons which have phonon-like characteristics, and surface phonon-polaritons on the compositions of ternary mixed crystals are nonlinear and different from those of the corresponding binary systems.