B—ISDN中的拥塞控制技术

Ｂ－ＩＳＤＮ是现代电信网的发展方向，拥塞控制技术则是其中的一个重要问题。由于Ｂ－ＩＳＤＮ采用新的信息传递方式－ＡＴＭ，使传统的拥塞控制方法不再适用。本文依据ＩＴＵ－Ｔ有关建议的最新内容对Ｂ－ＩＳＤＮ拥控制的基本思想、工作机制以及其中的主要功能作了较为详细的分析讨论，并提出了一些Ｂ－ＩＳＤＮ拥塞控制技术中尚需进一步研究的问题。     

B—ISDN中的拥塞控制技术

Ｂ－ＩＳＤＮ是现代通信网的发展方向，而其中中的拥塞控制技术则是一个重要方向。由于Ｂ－ＩＳＤＮ中采用新的传递方式－ＡＴＭ，使传统的网络拥塞控制方法不再适用。     

宽带综合业务数字网中的拥塞控制技术

宽带综合业务数字网中的拥塞控制技术段强宽带综合业务数字网（Ｂ─ＩＳＤＮ）是现代电信网的发展方向，拥塞控制技术则是其中的一个重要问题。由于Ｂ─ＩＳＤＮ采用新的信息传递方式─异步转移模式（ＡＴＭ），使传统的拥塞控制方法不再适用。本文依据国际电信联盟ＩＴＵ...     

ATM宽带网络流量与拥塞控制研究

文章阐明对ＡＴＭ网络进行流量与拥塞控制不仅是由ＡＴＭ网络的分组交换本质所决定，也是实现Ｂ－ＩＳＤＮ的基本要求，文章还对目前ＡＴＭ网络的ＡＢＲ流量与拥塞控制机制进行了评述，提出了ＡＢＲ流量控制尚待解决的一些问题。     

B—ISDN／ATM网络中的拥塞控制

给出Ｂ－ＩＳＤＮ／ＡＴＭ网络中的业务量类型，描述实时业务量，交互式业务量和成批业务量的拥塞控制，并讨论了用于这种网络的防止性拥塞控制方法。     

ATM通信技术

概述了ＡＴＭ通信技术的信元结构、交换方式、协议模式和拥塞控制等，指出了ＡＴＭ是Ｂ－ＩＳＤＮ的基础，已成为当今通信发展的方向。     

建设ISDN应注意的几个技术问题

为了提供多种信息，许多发达国家早就在搞综合数字风（ＩＳＤＮ）了。先是窄带的Ｎ－ＩＳＤＮ，进而是宽带的Ｂ－ＩＳＤＮ。预计到２０００年前后，Ｂ－ＩＳＤＮ将正式投入罗国对于ＩＳＤＮ也 重视，计划到２０１０年要实现相当规模的Ｂ－ＩＳＤＮ。建设ＩＳＤＮ，有很多技术问题，本文只对几个主要的，例如参考结构、ＩＳＤＮ的信令、ＡＴＭ（异步传送模式）及ＩＳＤＮ与各方面的配合作简要介绍。     

ISDN的现状和发展

９０年代将是ＩＳＤＮ和宽带ＩＳＤＮ迅速发展的年代，本文介绍了国外Ｎ－ＩＳＤＮ和Ｂ－ＩＳＤＮ的发展动向，并结合我国通信网的现状，对发展ＩＳＤＮ（Ｂ－ＩＳＤＮ）提出若干建议。     

宽带ISDN与ATM交换技术 第四讲 B－ISDN中的业务量控制

本文介绍了Ｂ－ＩＳＤＮ中业务量控制的原理和方法，讨论了连接／呼叫接纳控制（ＣＡＣ）和用法／网络参数控制（ＵＰＣ／ＮＰＣ）两个最基本的业务量控制功能，并对网络拥塞控制、业务量成形、优先级控制和快速资源管理等附加的控制功能作了简要的叙述。     

N—ISDN走出低谷B—ISDN迈向市场

本文介绍了全球Ｎ－ＩＳＤＮ的商用情况和Ｂ－ＩＳＤＮ的发展趋势，展示出Ｎ－ＩＳＤＮ走了低谷、Ｂ－ＩＳＤＮ迈向市场的美好前景。     

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.     

Nanoimprint Lithography -A Next Generation High Volume Lithography Technique

IntroductionNanoimprint Lithography is a well-acknowl-edged low cost, high resolution, large area pattern-ing process. It includes the most promising methods,high-pressure hot embossing lithography (HEL) [2],UV-cured imprinting (UV-NIL) [3] and micro contactprinting (m-CP, MCP) [4]. Curing of the imprintedstructures is either done by subsequent UV-lightexposure in the case of UV-NIL or by cooling downbelow the glass transition temperature of the ther-moplastic material in case of HEL…     

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.     

Influence of PVK ： NPB hole transporting layer on the characteristics of organic light-emitting devices

A doping system consisting of NPB and PVK is employed as a composite hole transporting layer （CHTL）. By adjusting the component ratio of the doping system, a series of devices with different concentration proportion of PVK ： NPB are constracted. The result shows that doping concentration of NPB enhances the competence of hole transporting ability, and modifies the recombination region of charge as well as affects the surface morphology of doped film. Optimum device with a maximum brightness of 7852 cd/m^2 and a power efficiency of 1.75 lm/W has been obtained by choosing a concentration proportion of PVK ： NPB at 1：3.     

New insert layer structure OLEDs

An insert layer structure organic electroluminescent device（OLED） based on a new luminescent material （Zn（salen）） is fabricated. The configuration of the device is ITO/CuPc/NPD/Zn（salen）/Liq/LiF/A1/CuPc/NPD/Zn（salen）/Liq/LiF/A1. Effective insert electrode layers comprising LiF（1nm）/Al（5 nm） are used as a single semitransparent mirror, and bilayer cathode LiF（1 nm）/A1（100 nm） is used as a reflecting mirror. The two mirrors form a Fabry-Perot microcavity and two emissive units. The maximum brightness and luminous efficiency reach 674 cd/m^2 and 2.652 cd/A, respectively, which are 2.1 and 3.7 times higher than the conventional device, respectively. The superior brightness and luminous efficiency over conventional single-unit devices are attributed to microcavity effect.     

Analysis of error performance on Turbo coded FDPIM

Due to variable symbol length of digital pulse interval modulation（DPIM）, it is difficult to analyze the error performances of Turbo coded DPIM. To solve this problem, a fixed-length digital pulse interval modulation（FDPIM） method is provided. The FDPIM modulation structure is introduced. The packet error rates of uncoded FDPIM are analyzed and compared with that of DPIM. Bit error rates of Turbo coded FDPIM are simulated based on three kinds of analytical models under weak turbulence channel. The results show that packet error rate of uncoded FDPIM is inferior to that of uncoded DPIM. However, FDPIM is easy to be implemented and easy to be combined, with Turbo code for soft-decision because of its fixed length. Besides, the introduction of Turbo code in this modulation can decrease the average power about 10 dBm, which means that it can improve the error performance of the system effectively.     

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.     

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.     

Preparation and Characterization of TaN ALD Precursors

High purity organic-tantalum precursors for thin film ALD TaN were synthesized and characterized.Vapor pressure and thermal stability of these precursors were studied.From the vapor pressure analysis,it was found that TBTEMT has a higher vapor pressure than any other published liquid TaN precursor,including TBTDET,TAITMATA,and IPTDET.Thermal stability of the alkyl groups on the precursors was investigated using a 1H NMR technique.The results indicated that the tertbutylimino group is the most stable group on TBTDET and TBTEMT as compared to the dialkylamido groups.Thermal stability of TaN precursors decreased in the following order:TBTDET ＞ PDMAT ＞ TBTEMT.In conclusion,precursor vapor pressure and thermal stability were tuned by making slight variations in the ligand sphere around the metal center.