密集波分复用技术及其应用

随着网络带宽的剧烈增长和对服务质量的要求不断提高，密集波分复用技术（DWDM）和全光网络正成为研究的热点。通过在一条光纤上传输多个波长的光信号，DWDM能够极大提高光网络的传输能力。在全光网络中，信息的传输和处理都是在光域中进行的。本文对近期的DWDM和全光网络的研究进行了回顾，特别关注了以IP over DWDM为基础的光因特网的进展。     

News & notes.

This column presents information of interest to Division 26 members. Included are a candidate's statement from Division member Ludy T. Benjamin, Jr., who is running for President of the American Psychological Association. Also included are a report on the February 1998 Meeting of the APA Council of Representatives; information about the Wallace Russell Fund, nominations for division offices, fellows nominations, and division membership; meeting announcements; and information about access restrictions to the Stanley Milgram papers. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

全光网络探索

全光网络(AON)的出现标志着网络传输技术又向前迈出了重大的一步,它与传统的传输网络相比具有卓越的性能,被称为第三代网络,不久的将来,它将成为电信、Internet等网络的核心,广电网络工作者应对该技术给予必要的关注与了解.     

National Training Conference in Community Psychology.

This article describes the National Training Conference in Community Psychology, which marked the culmination of several years of planning, starting in 1970, by the Executive Committee of the Division of Community Psychology (APA Division 27). The Conference was held in Austin, Texas, April 27-May 1, 1975, and was sponsored by the Community Psychology Training Program of the University of Texas at Austin Department of Psychology. The Conference served to bring together for informal meetings and discussions the older and newer community psychologists, especially those who had entered the field during the last 5 years, to critically assess the many problems facing community psychology and to examine community psychology's conceptual independence from both clinical psychology and community mental health. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

基于CDMA的多重数字水印

针对多用户共享版权时联合水印嵌入等需求,提出了基于CDMA的多用户多重数字水印算法。提出并实现了小波域直接嵌入(WD)和基于邻域线性预测值嵌入(WNLP)两种CDMA水印方案。分析了用户数量和嵌入深度对含印图像质量和提取水印质量的影响。实验结果表明,该算法能有效解决多重数字水印中水印碰撞和用户数量受限问题。     

无线局域网实时业务优先的调度算法

该文在无线局域网的MAC协议上,基于时分多址技术,提出了分离缓冲器调度控制算法,将业务分为实时性要求的和非实时性要求两类,并给实时性业务以高的优先级.仿真结果表明该算法满足了实时性业务的失效概率要求,一定程度上保证了网络的QoS.     

基于冲突关系的集合划分分类

介绍了中突关系的形式描述,研究了中突关系与相容的数学原理,构造了集合的划分算法,运用划分算法解决了补考安排问题.     

ITERATIVE RECEIVER FOR OFDM SYSTEMS BASED ON SEMI-BLIND CHANNEL ESTIMATION

In this paper we propose two iterative algorithms of joint channel estimation and symbol detection for Orthogonal Frequency Division Multiplexing （OFDM） systems. In which, superimposed pilot scheme is adopted and an initial Channel State Information （CSI） is obtained by employing a first-order statistic. In each subsequent iteration, we propose two algorithms to update the CSI. The Mean Square Error （MSE） of channel estimation and Bit Error Rate （BER） performance are given and simulation results demonstrate that the iterative algorithm using method B has good performance approaching the ideal condition.     

News and notes.

This section of News & Notes provides information for members of APA's Division 26. Topics covered include obtaining information about the Society for the History of Psychology; the Council of Representative Report from the Annual Meeting of the American Psychological Association from August, 2007; a call for papers for Cheiron: The International Society for the History of Behavioral and Social Sciences 40th Annual Meeting; and member news, including presentations, publications, appointments, and information about The New Dictionary of Scientific Biography. (PsycINFO Database Record (c) 2010 APA, all rights reserved)