TinyBGA256MB笔记本电脑内存

继１９９９年推出ＴｉｎｙＢＧＡ技术后,ＫｉｎｇＭａｘ日前又成功地推出了以ＴｉｎｙＢＧＡ技术封装的２５６ＭＢ笔记本电脑内存产品。该产品在ＴｉｎｙＢＧＡ封装技术上实现了新的突破,从而在高端市场创下了更小体积、更高容量、更佳效能的世界记录。在ＣｅＢＩＴ汉诺威展上,ＫｉｎｇＭａｘ的ＴｉｎｙＢＧＡ２５６ＭＢＳＯ－ＤＩＭＭ１４４ｐｉｎ内存产品被业界称之为“世界超峰技术”。ＴｉｎｙＢＧＡ２５６ＭＢＳＯ－ＤＩＭＭ１４４ｐｉｎ内存产品在１．１８英寸高的ＰＣＢ上,以ＴｉｎｙＢＧＡ新技术１１×１３ｍｍ的１２８Ｍｂｉｔ…     

IBM国际图联大会推出数字图书馆应用产品

在北京举行第６２届国际图书馆协会联合会大会上，作为最大的图书馆自动化专题参展商，ＩＢＭ公司展出了最新的解决方案──ＩＢＭ数字图书馆。ＩＢＭ宣布了ＩＢＭ数字图书馆１．０版，并展示了其最新技术及客户应用实例。展览期间举行的ＩＢＭ数字图书馆技术论坛和专题研讨会上，专家们还就全球图书馆信息技术的发展及我国图书馆自动化发展的现状，数字图书馆的先进技术及发展前景，图书馆网络技术以及数据库技术进行了研讨。ＩＢＭ数字图书馆１．０版最初为单机系统开发了软件包。这个软件包的服务器端可使用ＡＩＸ和ＯＳ／２的操作系统，…     

码分多址（CDMA）蜂窝移动通信（2）

码分多址（ＣＤＭＡ）蜂窝移动通信（２）吴家滨（广东省移动通信局）５ＣＤＭＡ数字蜂窝移动通信系统的容量在ＦＤＭＡ或ＴＤＭＡ蜂窝移动通信系统中，容量的计算是根据Ｃ／Ｉ的要求，求出频率重复使用次数Ｋ，再根据总的能使用的带宽Ｂ；和每个信道或等效信道的带宽Ｂｅ...     

欧美的数字声音广播（DAB）技术

本文介绍和比较了欧洲Ｅｕｒｅｋａ－１４７和美国ＵＳＡＤＲ两种数字声音广播体制，讨论了信源编码算法ＭＵＳＩＣＡＭ，以及编码正交频分复用（ＣＯＦＤＭ）和带内同频（ＩＢＯＣ）传输技术。     

东芝、IBM、西门子联合开发256MbDRAM

东芝、ＩＢＭ、西门子联合开发２５６ＭｂＤＲＡＭ据日本《ＳｅｍｉｃｏｎｄｕｃｔｏｒＷｏｒｌｄ》１９９５年第８期报道，东芝、ＩＢＭ、西门子联合开发２５６ＭｂＤＲＡＭ。通过采用０．２５μｍＣＭＯＳ及单元阵列面积小型化技术，其芯片面积仅为２８５．５ｍｍ２。该...     

数字音频广播

９２年４月开路展示了欧洲尤里卡１４７计划的数字音频广播（ＤＡＢ）成果，宣告了ＤＡＢ的诞生，各国竞相试验研究实施的方式，，国际标准化组织也积极开发ＤＡＢ标准的研究，全世界进入了ＤＡＢ时代。在频带选用方面，有欧洲的宽带新频段方式和美国在现有ＦＭ／ＡＭ频带内的方式；编码调制方面有欧洲的ＭＵＳＩＣＡＭ加ＣＯＦＤＭ和美国的ＡＴ￡Ｔ（或ＭＵＳＩＣＡＭ）加多频四相调制等。９４年美国ＥＩＡ和ＮＲＳＣ对其国内包括新     

ISO／IEC MPEG—2先进音频编码（一）

在对兼容性没有任何要求的条件下，ＩＳＯ／ＩＥＣＭＰＥＧ－２先进音频编码（ＡＡＣ）系统使ＩＳＯ／ＩＥＣＭＰＧＥ－２编码具有最好的音频质量，叙述了ＡＡＣ系统（ＩＳＯ／ＩＥＣ１３８１８－７）的主要特点，ＭＰＥＧ－２ＡＡＣ把高分辨率滤波器组，预测技术，霍夫曼编码的编码效率和其他功能结合在一起，可以在数据率可变的情况下，传输品质极高的音频。     

美国带内同频道数字音频广播（DAB）的开发状况

欧洲尤里卡１４７／ＤＡＢ方式在世界范围内推出后，很多国家正在对这种方式进行实验和开发。但是，美国广播界却另辟蹊径，他们正在开发一种不同于尤里卡１４７／ＤＡＢ的带内ＤＡＢ方式，该方式有两种：带内同频道ＤＡＢ方式（ＩＢＯＣ ＡＭ－ＤＡＢ，ＩＢＯＣ ＦＭ－ＤＡＢ）和带内邻频道ＤＡＢ方式（ＩＢＡＣ ＡＭ－ＤＡＢ，ＩＢＡＣ ＦＭ－ＤＡＢ）。本文详细介绍美国ＵＳＡ Ｄｉｇｉｔａｌ Ｒａｄｉｏ公司开发的带内同频     

CMA,PCS（3GM）与NⅡ／GⅡ

本文式图对当前移动通信发展中的几个热点问题联系起来探讨其发展趋势。首先是ＣＤＭＡ的优势２与总是何在。文中指出，ＣＤＭＡ的优势在容量，而问题在于它是功率和干扰受限系统。其次是Ｎ－ＣＤＭＡ在第二代和二代半移动通信中的应用前景，预计１９９７年将见分晓。Ｗ－ＣＤＭＡ将在第三代移动通信，即个人通信，例如ＩＭＴ－２０００和ＵＭＴＳ中成为优选方案之一。在未来的信息调整公路中Ｂ－ＣＤＭＡ将是解决无线接入的关键技术     

CDMA技术的新进展：一种扩频地址编码技术（LA—CDMA码）

蜂窝移动通信系统由于存在多种码间干扰而使其系统容量难以增加，ＣＤＭＡ技术在理论上可使其容量与ＡＭＰＳ相比扩大十多倍，但实际上并不如此理想。北京邮电大学李道本教授开发了一种扩频地址编码技术，使系统容量比ＩＳ－９５大了三倍以上。本文就此ＣＤＭＡ技术的新突破作一报导和介绍。     

Modified intraconnected bidirectional associative memory

A modified model for the intraconnected bidirectional associative memory (IBAM) is introduced in which there are not only interfield connections but also intrafield connections added in each neuron field. In the modified IBAM recall process, the intralayer feedback processes run parallel, instead of sequentially as in the IBAM, with the interlayer processes. This results in both removal of the complement encoding problem and relaxation of the continuity assumption for reliable recalls of the BAM.<>     

SOME STATISTICAL ANALYSIS OF THE RECALL PROBABILITY OF PARALLEL INTRACONNECTED BIDIRECTIONAL ASSOCIATIVE MEMORY

This paper addressed a statistical analysis for the recall of parallel intraconnected bidirectional associative memory-Modified Intraconnected Bidirectional Associative Memory (MIBAM) and proved the conclusions: two MIBAM with the equal total number of neurons have the equal recalling probability for m pairs of stored pattern pairs if m is not too large. So they have the same capacity and same error correcting ability, i. e., their performances are statistically equivalent. The results of simulation support the conclusions well.     

A NEW BIDIRECTIONAL ASSOCIATIVE MEMORY MODEL-HOMIBAM

A new bidirectional associative memory model named as HOMIBAM is introduced. The relationships of HOMIBAM with the models existed are pointed out. Both theoretical analysis and simulations show that the capacity and recall performance of HOMIBAM are superior to that of modified intraconnected BAM (MIBAM), higher-order BAM (HOBAM ) greatly.     

A new bidirectional associative memory model—HOMIBAM

A new bidirectional associative memory model named as HOMIBAM is introduced. The relationships of HOMIBAM with the models existed are pointed out. Both theoretical analysis and simulations show that the capacity and recall performance of HOMIBAM are superior to that of modified intraconnected BAM (MIBAM), higher-order BAM (HOBAM) greatly. Supported by Climbing Progamme-National Key Project for Fundamental Research in China     

Generalised intraconnected bidirectional associative memories

A general model of the intraconnected bidirectional associative memory (GIBAM) is proposed. In a GIBAM, states are represented by complex values on the unit circle of the complex plane, and the weight matrices are learned using the generalised inverse technique. The stability of the GIBAM is demonstrated by defining an energy function which decreases with a change in neuron states. Computer simulation demonstrates that the GIBAM has a much higher storage capacity and much better error correcting capability than Jengs modified IBAM     

安全向量优势协议及其应用

百万富翁问题是安全多方计算研究的热点问题之一,也是其他安全多方计算协议的基本构成模块.安全向量优势统计问题是百万富翁问题的推广,用于两方在不泄漏自己保密向量信息的前提下统计出满足大于关系的分量的数目.本文基于同态加密算法,通过对保密的数据进行编码,设计了一个计算百万富翁问题的协议,并利用模拟范例对协议进行安全性证明.然后利用这个新的协议作为基本模块,设计了一个向量优势统计协议,通过效率分析显示我们的方案是简单、高效的.最后将向量优势统计协议应用到整除判定问题和点与若干直线关系判定问题.     

Capacity reservation optimization for distributed satellite cluster networks

We investigate the problem of link capacity reservation in distributed satellite cluster networks. In the optimization problem, the objective is to minimize the link reservation cost under the link capacity constraints. The original optimization problem can be formulated as a set of the linear programs. For the small‐scale networks, the general linear program solvers have the capability to solve the problem within an acceptable time. To solve the problem in the large‐scale network, we propose a heuristic method on the basis of the alternating direction method of multipliers, in which the original problem is decoupled to parallel small problems that can be solved simply. In the heuristic, the upper and lower bounds are computed iteratively. When the upper and lower bounds are close enough, then the optimal value can be obtained approximately. The simulation results show that the proposed method is comparatively exact when the stopping criterion is properly chosen.     

Solving the routing and wavelength assignment problem in WDM networks for future planning - [Topics in optical communications]

In this article we define and analyze the routing and wavelength assignment problem by applying a virtual topology for both the optical network and the light paths. We introduce our developed algorithm to solve offline RWA problem. First the light path requests are constrained to repeated uniform distributed traffic. The reason is that this constraint permits us to study and analyze the behavior of the RWA problem. In addition, this constraint could be used as a benchmark to compare different algorithms. Then we relax the requests constraint to be non-uniform traffic. We show that the maximum number of assigned wavelengths depends on the number of traversed links, not on the shortest path length. Theorems are derived with proof to justify our algorithm. The effect of adding supplementary links to the WDM optical network is also explained to show how this approach could be used in the future planning for online operation. Finally, the result shows significant different in the number of wavelengths used compared to a recent backbone implemented network.     

A High-Capacity Steganography Scheme for JPEG2000 Baseline System

Hiding capacity is very important for efficient covert communications. For JPEG2000 compressed images, it is necessary to enlarge the hiding capacity because the available redundancy is very limited. In addition, the bitstream truncation makes it difficult to hide information. In this paper, a high-capacity steganography scheme is proposed for the JPEG2000 baseline system, which uses bit-plane encoding procedure twice to solve the problem due to bitstream truncation. Moreover, embedding points and their intensity are determined in a well defined quantitative manner via redundancy evaluation to increase hiding capacity. The redundancy is measured by bit, which is different from conventional methods which adjust the embedding intensity by multiplying a visual masking factor. High volumetric data is embedded into bit-planes as low as possible to keep message integrality, but at the cost of an extra bit-plane encoding procedure and slightly changed compression ratio. The proposed method can be easily integrated into the JPEG2000 image coder, and the produced stego-bitstream can be decoded normally. Simulation shows that the proposed method is feasible, effective, and secure.      

基于频谱编码技术的OCDMA系统

光码分多址（OCDMA）系统中的地址码采用双极性码是一种较好的选择,但需要解决含有成分的地址码不能在光信道中直接传输的问题。频谱编码（spectral encoding）技术不但能有效解决这一难题,并有助于全光OCDMA的实现。在分析频谱编码的理论基础的前提下,介绍了几种基于双极性码和频谱编码的OCDMA的实现方案,并探讨了系统 前景及需要解决的技术问题。