方正颐和A450C 笔记本

方正颐和A450C堪称“动力十足”,它配置相对较高、性能较好,在处理器技术IDE设备控制、总线速度、输入输出系统(I/O)等方面均采用目前同类笔记本电脑相对领先的技术。     

用于多处理器系统的32位可编程信号处理机

本文叙述了32位可编程信号处理机的结构、系统设计及程序操作,它可以用于单处理器或多处理器系统的场合。本处理机设计的特点包括:较高的吞吐量;通过可编程的输入/输出(I/O)矢量中断或分布式直接访问内存(DMA)实现通用输入一输出结构;编程相当简易以及使用的部件数量少。     

基本的输入/输出操作

5.1.概述上一章已介绍了基本的I/O接口技术和部件,也就是说用户可以根据外部设备的要求选择并行或串行接口方式。下一个问题就是处理MPU和外部设备之间的数据交换,也就是选择对数据进行调度的方式。通过I/O口对外设进行操作,通常是与MPU无关的。但是在传送数据过程中,应使1/O操作与所执行的程序同步起来。依据对数据交换进行控制和同步的方法,将输入/输出操作分为三种基本类型,即:     

重新考虑DSP的设计方法

一直到现在,数字信号处理(DSP)产品的增长是通过两种方法实现的.一种是制造极高速倍增器和乘法-累加器(MAC),并把它们与位片机组合起来以实现最大的吞吐量;另一种是把所有的通用元件组合到一块芯片上(即处理器、MAC、存储器),并调整处理器指令组以提供最大的I/O带宽和最高的MAC利用.     

激流勇进 变中求胜——Specialix在变化市场中的策略

串行通讯技术是许多信息技术解决方案中基本的,不可缺少的组成部分。但目前大部分用户不再使用串行I/O来将不灵活的终端接到UNIX服务器上,不过仍然还有许多更加重要的任务和各种场合需要使用串行通讯技术。需求的变化使得 Specialix投资方向也发生了变化. Secialix是一家全球性的生产串行通讯产品的私营公司,总部位于Surrey的Byfleet。 Specialix的产品能满足所有工业认定的发射和     

Dell 服务器强锋97攻势展开

Dell PowerEdge 4100借助于Dell在业界标准技术方面的丰富经验,采用稳定可靠的元部件,使得性能水平达到了较高的境界。Dell设计的母板包括对称多处理(SMP)支持,两个Pentium Pro处理器ZIF插座,支持PCI 2.1的先进Intel 82440FX芯片组,以及集成式Ultra/Wide SCSI支持。只需一台拥有256KB高速缓存的180MHz Pentium Pro处理器,或一台拥有512KB高速缓存的200MHz Pentium Pro处理器,就能满足客户的需要。 PowerEdge 4100采用标准64MB ECC RAM,借助8个DIMM插座可升级至1GB。 PowerEdge 2100的Pentium Pro处理器是性能最优的业界标准处理器。PowerEdge 2100配有180MHz和200MHz两种Pentium Pro处理器。为了满足高性能的硬盘I/O需求,PowerEdge 2100在系统板上集成了Ultra/Wide SCSI-3控制器,这样就可以实现最高的数据传输速率,达到每秒40MB,这是今天许多服务器普通使用的Fast SCSI-2控制器的两倍。PowerEdge 2100的设计充分考虑到了网络的未来发展需求。三个开放PCI扩展槽和三个开放EISA扩展槽为高性能扩充卡留下了充足的空     

恒丰银行报文管理外汇清算系统架构与实施

针对恒丰银行现行SWIFT报文管理和外汇清算业务的特点和原有操作的局限性，作者提出了一个报文管理和外汇清算系统的架构、设计思路，由恒丰银行和南京星有田科技发展有限公司共同研发实施，系统寞施后提高了恒丰银行swift报文管理和外汇清算的处理效率，带来明显的经济效益。     

多总线结构MHAL路由方法

在分析传统调制解调级硬件抽象层（Modem Hardware Abstract Layer,MHAL）路由方法局限性的基础上,提出了一种多总线结构MHAL路由方法，并详细介绍了该方法的设计实现及验证。基于多总线结构MHAL路由方法在不违反软件通信结构规范的前提下，解决了传统方法不能解决的处理器间多总线路由、处理器多端口路由以及数据包路由转发问题。该技术已在某大型软件无线电系统中得到应用。     

ET200M分布式I/O在电气自动化中的应用研究

介绍了ET200M分布式I/O在电气自动化中的组态结构。该方案简单、实用,对SIEMENS远程I/O系统组态有一定的参考价值。     

基于FPGA的动态图形显示

在现在的数字系统设计中,FPGA发挥着越来越重要的作用。首先分析了FPGA的内部结构特点,对FPGA设计技术进行了详细阐述,针对现代数字系统的特点,研究了FPGA的设计流程。其次,简要介绍了SOPC技术,SOPC是Altera公司提出的一种灵活、高效的片上系统设计方案。它将处理器、存储器、I/O口等系统设计需要的组件集成到一个PLD器件上,构建成一个可编程的片上系统。接下来,介绍了VGA的相关知识.VGA（视频图形阵列）作为一种标准的显示接口得到广泛的应用。笔者依据VGA显示的原理,＂抛弃＂VGA显示专用芯片,采用FPGA（现场可编程门阵列）设计VGA接口可以将要显示的数据直接送到显示器。最后,在Altera公司的开发软件QuartusⅡ中,利用VHDL语言,实现模块的设计,达到图像动态显示的目的。     

战术数据报文通用描述模型设计

各军兵种/业务部门战术数据报文标准的差异性,给不同战术数据指挥系统之间的 报文解析带来困难,成为制约战术数据指挥系统互操作的“瓶颈”。为了实现不同军兵种/ 业务部门之间的报文交互,从战术数据指挥系统自动化解析与展现的角度,建立了战术数据 报 文通用描述模型,重点设计了表现层模板的描述规则,并给出了XML报文模板实例。     

改进校准技术的转发器输入输出特性测试方法

当卫星发射定点后,必须对在轨卫星通信有效载荷(即转发器)的性能进行测试。输入输出特性是转发器的一项重要技术指标。本文在参考国家标准和INTELSAT测试方案的基础上提出一种改进校准技术的转发器输入输出特性测试方法,详细介绍了该方法的测试原理,同时还提出一种无需精确测量卫星信道传输时延的解决收发信号同步的方法。该方法减少了误差因素,提高了测试精度,而且使在轨测试系统的校准由程序自动执行,提高了测试效率。     

R&;D,International Trade and Creative Destruction—Empirical Findings from Finnish Manufacturing Industries*

The determinants of productivity-enhancing micro-level restructuring are examined empirically with a panel of the twelve Finnish manufacturing industries. It is hypothesized that R&D leads to productivity diversity among plants, which in turn leads to the gradual reshuffling of input shares in the presence of dynamic competitive pressure. The effect of the creative destruction on industry productivity growth is measured with the between-component of productivity decomposition. Econometric results indicate with reasonable robustness that R&D generates creative destruction with a lag of several years. Some evidence is found that imports stimulate productivity-enhancing restructuring, especially when domestic R&D is low.JEL classification: O12, 014, 019, O31, O47*This paper is based on the chapter 8 of my PhD thesis which has been accepted by the Helsinki School of Economics (2003). The research has received financial support from Tekes (the National Technology Agency), and from the Yrjö Jahnsson Foundation. This paper has benefited from comments by Petri Böckerman, Pekka Ilmakunnas, Kabor Kezdi, and Petri Rouvinen, to whom I am grateful. I am also thankful to the referees for helpful comments. Lisa Roponen has checked my English. An earlier version of this paper has been presented at the EARIE 2002 conference in Madrid and at the Summer at CEU Workshop in Budapest in 2003. Data work and computations have been carried out at Statistics Finland, in accordance with the terms and conditions of confidentiality. I also wish to thank many individuals at Statistics Finland for their guidance regarding the properties of the data. Please contact the Research Laboratory of the Business Structures Unit, Statistics Finland, FIN-00022, Finland, for access to these data. The usual disclaimer applies.     

The Two Faces of R&D: Does Firm Absorptive Capacity Matter?

This paper examines the dual effect of firm R&D efforts on productivity growth for Swedish manufacturing firms. The R&D efforts do not only stimulate innovation but also enhance firms?? ability to identify, assimilate and exploit new knowledge from the environment (Cohen and Levinthal. Economics Journal 99:569?C596, 1989). In this paper, we assume that the principal channel of transmission of new knowledge is through I/O linkages. Our econometric evidence suggests that in addition to the firm??s own R&D activities, R&D spillovers embodied in traded goods within the industry, others imported from abroad, and technology spillovers transferred from the technological frontier within an industry are important determinants of firms?? productivity growth. Results suggest that domestic R&D spillovers following the I/O links between industries are of minor importance in this respect. We also analyze whether firms?? absorptive capacity matters for productivity growth. Analyzing absorptive capacity is particularly important for assessing the effective contribution of spillovers from other firms. The effect of a firm??s absorptive capacity is found to interact positively with imported R&D spillovers, whereas domestic rents spillovers seem to play a minor role for productivity growth.     

基于TCP/IP的嵌入式WebServer网络测控系统设计

本文研究基于TCP/IP协议栈的嵌入式系统在网络智能设备中的测控应用设计。以Rabbit2000网络微处理器和Dynam ic C软件开发环境为例,阐述构建嵌入式W ebServer的具体技术及相关的实现方案;详细介绍了实现TCP、UDP报文进行网络通信、串行口数据通信和对网络智能设备的测控技术等,并给出系统硬件原理框图和有关软件实现的程序代码及流程图。     

Domestic vs. International Spillovers: Evidence from Swedish Firm Level Data

This paper investigates the association between total factor productivity growth and the R&D expenditures of Swedish manufacturing firms in the presence of domestic- and international R&D spillovers. The paper assumes that the principal channel of transmission of new technology is through I/O relations. Econometric evidence suggests that international as well as domestic inter-industry R&D spillovers are important determinants of firms’ productivity growth in the long run. The R&D spillovers generated within the industry and following I/O links seem to be of minor importance in explaining productivity growth. It seems likely that within-industry productivity spillovers follow other channels than I/O flows, such as horizontal spillovers through copying of new products and processes, or labour turnover. The use of a convergence parameter is one way to check for such within-industry technology flows. Our results indicate that a catch-up process exists by which the non-frontier firms in the Swedish manufacturing sector absorb knowledge spillovers from the leading firms in the industry. Finally, a firm’s own R&D efforts are found to be more or less positively correlated with the TFP growth, maybe the contribution from R&D efforts in some sense are underestimated.     

A Need For a Substantial Tightening of Merger Control? Comment on Tichy

This paper responds to Tichy's analysis of M&A activity and in particular to the lessons Tichy draws from his review. The paper focuses on a number of policy conclusions reached by Tichy, which I believe are in sharp contrast with the current consensus on the economic analysis of potentially problematic mergers. In particular, I explain why I believe that a number of changes to merger control activity suggested in the paper (such as a general ban on particular types of mergers including mergers reducing the number of firms below five, vertical mergers in network industries, and acquisition of firms producing substitutes in the field of the former public utilities) would actually be detrimental to economic efficiency by generating a system that would not have the necessary flexibility to precisely assess on a case-by-case basis whether particular mergers might have an anti-competitive effect.     

基于内部标签的综合接入系统输入输出调度方案

本文在介绍了综合业务接入系统的基本结构基础上 ,介绍了自治系统内部标签 (ILP)信令格式 ,提出了一种新的基于优先级的参数自适应轮循调度 (Priority -basedParameterAuto -adaptiveRound -robinScheduling)方案 ,以及该方案在基于ILP的综合接入系统I/O调度中的实现方法 ,并对几种调度方案的性能进行了实验比较     

基于PROFIBUS-DP的环境参数采集系统设计与应用

针对易燃易爆介质生产和存放安全性要求,提出了基于PROFIBUS-DP的环境参数采集 系统解决方案,完成了系统结构和控制过程设计。结合PROFIBUS-DP开放式现场总线描述了 系统网络通信协议,下位机采用S7-200系列CPU模块和I/O模块构成,上位机采用与设备无关 的MCGS作为监控系统,实现了对采集的数据进行集中管理和实时监控。实际运行证明,系统 性能稳定,可靠性及过程自动化控制效率得到了显著提高,达到了设计目标。     

外商直接投资、经济集聚与绿色经济效率——理论分析与中国经验

现有关于FDI如何影响绿色发展的文献往往忽略经济集聚的作用,文章构建"FDI-经济集聚-绿色经济效率"的逻辑框架,并基于2004~2018年城市面板数据进行验证。研究发现:(1)FDI对绿色经济效率扮演着双重角色,其既通过产业结构产生负面效应,又通过经济集聚与节能减排技术发挥正面效应;(2)FDI总体上有利于提升绿色经济效率,这得益于经济集聚在削弱FDI产业结构效应的同时,强化其节能减排技术效应;(3)无论是全国还是东部地区,当经济集聚适度时,FDI与经济集聚能形成协同效应,从而促进绿色经济效率;当经济集聚超过临界值,全国与东部地区呈现拥挤效应,而中西部地区呈现集聚效应,由此致使FDI对绿色经济效率的影响效果存在显著的区域差异。