3G标准的技术性比较分析与研究

介绍了3G技术在国内外的发展情况，阐述了发展趋势，对3G技术的分类和所采用的主流技术、标准化情况进行了论述，并对CDMA2000，WCDMA和TD-SCDMA三种3G的三大主流应用技术标准进行比较分析。     

Windows2000环境下实时控制系统的软件实现

文章介绍了在windows2000环境下通过编写WDM（Windows Driver Model）设备驱动程序实现实时数据采集和控制的一种方法。采用研华数据采集卡PCL818L产生中断信号．通过编写WDM驱动程序实现了在windows2000环境下转台的位置控制。并在实验中调试通过。实验结果表明：在采样频率为1KHz的情况下。控制系统很好实现了输出对输入的跟踪，证明了采用方法的正确性。该方法解决了windows2000环境下的实时性问题，为在windows环境下实时控制系统的实现提供了有益的尝试。     

Cif2000平台下的核磁共振测井解谱方法研究

介绍了在Cif2000多井解释平台下的核磁共振解谱方法与编程实现。解谱采用加入平滑因子后在特征矩阵的奇异值分解中截去小的非零奇异值的方法，可以在低信噪比时得到稳定的弛豫谱，在油田实际应用中证明了该方法的有效性。根据该方法在Cif2000平台上编制了完整的解谱处理程序，可以直接用于油田的生产实际。     

无线智能网技术

本介绍CDMA无线智能网（WIN）的产生背景、技术标准、提供的业务、与GSM移动智能网技术上的差异以及它在实际工程中的应用，最后对WIN的发展进行展望。     

Performance modeling and evaluation of data/voice services in wireless networks

Application-level performance is a key to the adoption and success of the CDMA 2000. To predict this performance in advance, a detailed end-to-end simulation model of a CDMA network is built to include application traffic characteristics, network architecture, network element details using the proposed simulation methodology. We assess the user-perceived application performance when a RAN and a CN adopt different transport architectures such as ATM and IP. To evaluate the user-perceived quality of voice service, we compare the end-to-end packet delay for different vocoder schemes such as G.711, G.726 (PCM), G.726 (ADPCM), and vocoder bypass scheme. By the simulation results, the vocoder bypass scenario shows 30% performance improvement over the others. We also compare the quality of voice service with and without DPS scheduling scheme. We know that DPS scheme keep the voice delay bound even if the service traffic is high. For data packet performance, HTTP v.1.1 shows better performance than that of HTTP v.1.0 due to the pipelining and TCP persistent connection. We may conclude that IP transport technology is better solution for higher FER environment since the packet overhead of IP is smaller than that of ATM for web browsing data traffic, while it shows opposite effect to the small size voice packet in RAN architecture. We show that the 3G-1X EV-DO system gives much better packet delay performance than 3G-1X RTT. The main conclusion is that end-to-end application-level performance is affected by various elements and layers of the network and thus it must be considered in all phases of the development process. Jae-Hyun Kim He received the B.S., M.S., and Ph.D. degrees, all in computer science and engineering, from Hanyang University, Ansan, Korea, in 1991, 1993, and 1996 respectively. In 1996, he was with the Communication Research Laboratory, Tokyo, Japan, as a Visiting Scholar. From April 1997 to October 1998, he was a post-doctoral fellow at the department of electrical engineering, University of California, Los Angeles. From November 1998 to February 2003, he worked as a member of technical staff in Performance Modeling and QoS management department, Bell laboratories, Lucent Technologies, Holmdel, NJ. He has been with the department of electrical engineering, Ajou University, Suwon, Korea, as an assistant professor since 2003. His research interests include QoS issues and cross layer optimization for high-speed wireless communication. Dr. Kim was the recipient of the LGIC Thesis Prize and Samsung Human-Tech Thesis Prize in 1993 and 1997, respectively. He is a member of the Korean Institute of Communication Sciences (KICS), Korea Institute of Telematics and Electronis (KITE), Korea Information Science Society (KISS), and IEEE. Hyun-Jin Lee received the B.S. degree in electrical engineering from Ajou University, Suwon, Korea, in 2004, and is working toward the M.S. degree and Ph. D. degree in electrical engineering at Ajou University. He has been awarded Samsung Human-Tech Thesis Prize in 2004. His research interests QoS, especially network optimization and wireless packet scheduling. He is a member of the KICS. Sung-Min Oh received the B.S. and M. S. degrees in electrical engineering form Ajou University, Suwon, Korea, in 2004, and is working toward the Ph. D. degree in electrical engineering at Ajou University. His research interests QoS performance analysis and 4G network. He is a member of the KICS. Sung-Hyun Cho received his B.S., M.S., and Ph.D. in computer science and engineering from Hanyang University, Korea, in 1995, 1997, and 2001, respectively. From 2001 to 2005, he has been with Samsung Advanced Institute of Technology, where he has been engaged in the design and standardization of MAC and upper layers of B3G, IEEE 802.16e, and WiBro systems. He is currently a MAC part leader in the telecommunication R&D center of Samsung Electronics. His research interests include 4G air interface design, radio resource management, cross layer design, and handoff in wireless systems.     

选煤综合网络管理信息系统的设计与实现

从中国煤炭加工利用协会的实际需要出发，用POWERBUILDER7．0和MS SQL Server2000开发基于客户机/服务器体系结构的选煤综合网络管理信息系统。本系统设计具有友好的用户界面，可以方便地输入数据、编辑表格，还有打印、数据统计与记录查询等功能。     

AMBE-1000声码器接口电路设计方法

DVSI公司的AMBE-1000声码器芯片是一款高性能的全双工、实时语音压缩编解码芯片,可以应用于卫星通信、保密通信、视频会议等领域.文中简要介绍AMBE-1000声码器的A/D-D/A接口以及信道接口的工作原理;结合实例分别给出了AMBE-1000声码器与PCM编解码器MC14LC5480的A/D-D/A接口电路、与单片机AT89C51的信道接口电路的设计方法;最后指出了电路设计中应该注意的问题.     

The Region 1 & 3 Broadcasting‐Satellite Service Plan after WRC‐03

The 1977 Broadcasting‐Satellite Service (BSS) Plan for Region 1 & 3 had been widely acknowledged to be out‐of‐date by the late 1980s. Development of digital modulation in the early 1990s provided an opportunity to update the technical provisions of the Plan to make it more economically viable. After a decade of work and three World Radiocommunication Conferences (WRCs), the revision of Region 1 & 3 BSS Plan was finally completed in 2003. The new Plan increased channel assignments from 5 to 10 analog‐equivalent channels for each country in Region 1, and from 4 to 12 channels for each country in Region 3. Yet, despite the increase in capacity, the new Plan is surprisingly similar to the original one in terms of the technical parameters. It is still based on national coverage, and the channel plan, orbital location, orbital spacing, and polarization are also the same. As a result, the new Plan is no more economically viable to implement than the old. To create economically viable BSS systems would most likely require modifications to the assignment in the Plan. Yet, modification procedures were made more difficult to apply after replanning. Less future implementation of BSS networks than would otherwise have occurred can be expected, and an inefficient usage of these frequency bands will likely result. On the other hand, less implemented systems will mean more capacity set aside for future use. This is important for countries that currently do not have satellite operations. In the end, BSS replanning reflects the eternal conflict between efficient usage and guaranteed future access. Copyright © 2005 John Wiley & Sons, Ltd.     

铸型尼龙改性的研究进展

铸型尼龙产品广泛地用于各种机械零件，改性后的铸型尼龙，可克服其自身的缺点，满足工业应用的要求。文章就我国近年来在铸型尼龙改性研究方面的情况及不同的改性方法做了详细的介绍。     

JPEG2000图像压缩标准及其关键算法

JPEG2000是为适应不断发展的图像压缩应用而出现的新的静止图像压缩标准。阐述了JPEG2000图像编码系统的实现过程，对其中采用的基本算法和关键技术进行了描述，介绍了这一新标准的特点及应用场合，并对其性能进行了分析。