敏捷开发研究

敏捷开发是以用户的需求进化为核心,迭代式的,循序渐进的开发模型。敏捷开发通过快速的开发迭代,更快的完成产品开发,更快的响应客户需求的变化。本文着重介绍Scrum开发框架,以及敏捷开发的优势。     

嵌入式应用程序开发教学改革探讨

着重分析探讨当前嵌入式应用程序开发教学的教学内容及组织形式,针对学生学习嵌入式应用程序开发的学习现状,提出面向技术发展的嵌入式应用程序开发教学内容,包括嵌入式应用程序开发的程序开发模式的更新、开发语言的更新及驱动型项目的教学内容改革措施。     

ISD系列语音芯片开发平台的设计

针对当前语音开发中ISD系列录放芯片开发中的不便，提出了一种设计ISD智能开发平台的思想，并介绍了开发平台的设计思路、功能以及开发完成的软件运行环境。     

广州南沙企业废水回用率低于六成将被取缔

日本揖斐电为了进一步增强企业竞争力,着手进行组织调整,强化面向新产品开发人研究开发体制,努力改善和提高收益能力,以封装基板和印制电路板所组成的电子相关部门,选定以下四项作为新产品开发计划：下一代倒装芯片封装基板的开发;积层多层板技术的开发;刚挠结合电路板的开发;埋置元件印制电路板的开发。为了增强研究开发能力,准备增加研究开发费用的投入。     

浅谈敏捷开发与其他传统开发方式的区别

敏捷开发是目前较流行的一种软件开发方法,它汲取了多种传统软件开发方法的优点,但也区别于传统的软件开发方法。本文就敏捷开发和最常用的迭代式开发、瀑布式开发、螺旋开发作了一定的比较,重点阐述了敏捷开发的优点和特点。     

电视机的虚拟开发与设计（一）--电子元器件的虚拟开发设计

本文主要应用虚拟技术对电视机进行开发,在设计和开发过程中,主要对电视机的基本结构如电视机外壳、电子元器件、连接导线和PCB等结构要素进行交互操作、场景开发和动画控制,给出了详细的开发过程和开发效果图,对于电视机的开发具有一定的借鉴作用。     

嵌入式系统比较

简单介绍了嵌人式开发系统的基本概念,详细比较了市场上的主要商用嵌入式开发系统的主要特点和收费方式,阐述了在选择商用嵌入式开发系统时需要着重考虑的因素,为用户初步了解嵌入式开发系统,进而选择嵌入式开发系统进行开发,提供了一定的参考依据。     

单片机开发系统综述

简单介绍了单片机开发系统的概念、功能及分类 ;然后具体介绍单片机开发系统的构成 ,包括开发工具和开发过程以及单片机开发系统的选择。     

单片机开发系统综述

简单介绍了单片机开发系统的概念、功能及分类；然后具体介绍单片机开发系统的构成，包括开发工具和开发过程以及单片机开发系统的选择。     

嵌入式开发成熟度模型与持续性改进

适用于嵌入式开发团队的嵌入式开发成熟度模型和用于工程实施的持续改进措施,能保证嵌入式系统开发工程的质量。逐级递进设计过程不规范、缺乏设计流程持续性改进、开发模式混乱、需求分析随动性差等是嵌入式系统开发过程中必须解决的问题。为了增强工程实践应用,基于嵌入式系统开发过程的ESD-CMMI五级模型,总结了嵌入式系统本身开发特征,探讨了ESD-CMMI模型所对应的持续性改进方向,给出了嵌入式系统开发持续改进的行动步骤。     

Design of wideband circularly polarized aperture-coupled microstripantennas

Two variations of a novel feeding technique for a wideband circularly polarized aperture-coupled microstrip antenna are described. Prototype designs for wideband linearly polarized elements are first presented, and then used for circularly polarized designs. Techniques used for design of the feed network are detailed, for both series feed and parallel feed versions. Experimental results are shown for each antenna, and results for the two designs are compared. The impedance and axial ratio bandwidths for these antennas are among the best yet achieved for microstrip antenna elements. Several design variations are also discussed     

A linear, time-varying system framework for noniterativediscrete-time band-limited signal extrapolation

A technique for the analysis and design of noniterative algorithms for discrete-time, band-limited signal extrapolation is described. The approach involves modeling the extrapolation process as a linear, time-varying (LTV) system, or filter. Together with a previously developed Fourier theory for LTV systems, this model provides a frequency-domain transfer function representation for the extrapolation system. This representation serves as a powerful tool for characterizing and comparing the reconstruction properties of several well-known least squares optimal algorithms for band-limited extrapolation. Moreover, the frequency-domain setting provides a conceptually attractive means for understanding the process of extrapolation itself. Additionally, a least squares approximation methodology for designing LTV filters for band-limited extrapolation is developed. The design technique is shown to unify a broad class of algorithms for extrapolating discrete-time data and, further, to provide a means for designing new and improved extrapolation algorithms     

一种基于CCD的非接触尺寸测量系统

设计了一种基于CCD的非接触尺寸测量系统.运用亚像素边缘检测法对圆环进行边缘检测,完成对圆环的非接触尺寸测量.利用数据库实现对测量数据的存储管理及网络传输.通过实验证明:对圆环测量精度外径误差0.005 mm,内径误差0.001 mm,壁厚误差0.015 mm,整体绝对误差小于0.02 mm,相对误差小于0.07％,满足了工程高精度测量要求.本系统适合有危害性的工业现场环境,数据的存储管理功能也给实际应用带来很大便利.     

Final call: CPR's fall meeting in Boston on Oct. 25‐26

It's last call for three CPR doings: for the Fall Meeting in Boston later this month, for three trainings, and for nominations for the 2007 CPR Awards. Also, CPR member options for signing up for free electronic copies of Alternatives     

Information Model for Resource of ASON Control Plane

1　Introduction　Opticalnetworkshavebecomemorecomplicatedthanbefore ,andneednetworkmanagement.InASON ,theControlPlane (CP)isanewnetworkcomponent[1～ 3] ,inordertomanagethenewemergedresources ,anin formationmodelforCPisrequired .　TheReferenceModelofOpenDistributedProcessing(RM ODP) providesanobjectorientedframeworkfordistributedmanagementsystemsthatallowsuser sdif ferentrequirementsformanagementapplications[4 ] .RM ODPhasprovideduswithanetworkmanagementviewpoint,anditprovidesfiveview…     

Rain attenuation measurements over New Delhi with a microwave radiometer at 11 GHz

Rain attenuation measurements over New Delhi carried out with a microwave radiometer installed at the National Physical Laboratory (NPL), New Delhi and operating on 11 GHz for a period of more than three years are presented. For 0.01 percent of time for the period June 1977-April 1978, the attenuation exceeded for the monsoon period is 14.0 dB whereas for the whole year, it exceeds 10.4 dB. During the winter for the same percentage of time, the attenuation exceeded 1.5 dB, whereas for March-April it exceeds 0.5 dB. For the period May 1978-June 1980, it is observed that for 0.01 percent of time the attenuation for the whole year exceeds 9.0 dB. During the winter for the same percentage of time, the attenuation exceeds 1.4 dB whereas for March-April it exceeds 0.4 dB. A comparison of attenuation over New Delhi and those reported elsewhere are discussed. Yearly and worst month time ratio over New Delhi are given also as the values reported for the European region. Comparison of the attenuation distribution and the rate of surface rainfall measured with a rapid-response rain gauge are also given. The comparison shows that for the monsoon period and for 0.01 percent of time, the attenuation value exceeded for 14 dB corresponds to the surface rainfall rate of 140 mm/h. For the monsoon of 1978, 1979, comparison shows that for 0.1 percent of time, the attenuation value exceeded for 9.0 dB corresponds to the surface rainfall rate of 90 mm/h. Variation of attenuation and effective path length for various rainfall rates and elevation angles are also given.     

Characterization and performance evaluation of differentialshielded cables for multi-Gb/s data-rates

This paper compares several differential cable characteristics that were evaluated for multi-Gb/s data-rates for both data and clock paths for 1-10 m lengths. Time-domain measurements are shown for the unassembled and connectorized cables and for representative card-plus-cable signal paths and the performance limiting factors are highlighted. Techniques are shown for developing coupled-line models for odd and even excitations for all the components in a full chip-to-chip path in order to make realistic data-rate predictions     

Detection of Modulated Gaussian Signals in Noise

A method using Hermite polynomials is utilized for analyzing the outputs of νth-law devices for inputs of modulated Gaussian signals and zero-mean Gaussian noise. New results are developed for the output correlation functions, and techniques for obtaining closed-form expressions are pointed out. Output signal-to-noise ratios for various input carrier-to-noise-power ratios are calculated, and plots are shown for a single sinusoidal modulating signal. Results are derived to show the existence of a theoretical maximum for the output signal-to-noise ratio. The method can be directly applied for the case of general Fourier expandable signals modulating a Gaussian carrier.     

Crosstalk between microstrip transmission lines

Methods for prediction of crosstalk between microstrip transmission lines are reviewed and simplified for the weak-coupling case. Classical coupled transmission line theory is used for uniform lines, and potential and induced EMF methods are used for crosstalk between nonuniform lines. It is shown that the potential method is equivalent to classical coupled transmission line theory for the case of uniform lines. An experiment was performed for uniform coupled microstrip lines for frequencies from 50 MHz to 5 GHz, and good agreement between theory and measurement was obtained for both near- and far-end crosstalk     

General coupling matrix synthesis methods for Chebyshev filteringfunctions

Methods are presented for the generation of the transfer polynomials, and then the direct synthesis of the corresponding canonical network coupling matrices for Chebyshev (i.e., prescribed-equiripple) filtering functions of the most general kind. A simple recursion technique is described for the generation of the polynomials for even- or odd-degree Chebyshev filtering functions with symmetrically or asymmetrically prescribed transmission zeros and/or group delay equalization zero pairs. The method for the synthesis of the coupling matrix for the corresponding single- or double-terminated network is then given. Finally, a novel direct technique, not involving optimization, for reconfiguring the matrix into a practical form suitable for realization with microwave resonator technology is introduced. These universal methods will be useful for the design of efficient high-performance microwave filters in a wide variety of technologies for application in space and terrestrial communication systems