基于Zynq-7000的宽幅视频处理系统设计与实现

针对安防监控与智慧交通领域无盲区视频摄录的需求,基于Zynq-7000平台优势进行宽幅视频处理软硬件系统的设计。通过研究基于嵌入式系统的多路视频实时拼接技术,设计并实现了以XC7Z020芯片为核心的视频处理板卡,在双核ARM Cotex-A9硬核处理器端服务程序协同调度下,基于片内FPGA硬件加速能力实现多通道视频实时采集与预处理、投影变换、图像融合,进而形成完整宽幅视频画面,通过远程客户端实现定制化的视频摄录功能。测试结果表明,该系统是兼具稳定的性能和灵活区域部署能力的便携式解决方案。     

3G网家庭状况远程实时监控系统的研究

针对传统监控系统中无法联网以及查询取证比较困难等不足,提出一种基于3G网络的B/S方式的嵌入式家庭状况远程实时监控系统的实现方案。该方案通过构建嵌入式服务器,完成对视频的采集、处理、存储和传输。服务器端采用基于ARM11硬件平台以及嵌入式Windows CE软件平台,可借助Windows CE操作系统的友好人机界面查看历史监控记录。试验证明,系统具有实时性强、交互性好以及开发成本低等特点。     

基于ARM9处理器的网络视频监控系统设计

设计了一种以高性能DSP及ARM9处理器(ARM940T核)为主要部件的网络视频监控系统,重点分析了H.264算法特点及其处理方法,并对监控系统的视音频采集压缩卡进行了设计;通过嵌入式Linux操作系统融合整个系统,形成了一套完整的网络监控系统解决方案,最终可实现网络监控系统的小型化;通过对实际监控系统网络数据传输、数据存储及视频画面质量等各项指标测试、比对,达到了设计中的要求;采用DSP进行H.264算法处理图像质量好,压缩码流便于ARM处理器处理,提高了数据处理运行速度.     

基于嵌入式Web服务器家居视频监控的研究

针对智能家居的远程监控问题提出了一种基于ARM,Linux和计算机网络的视频监控系统。该系统以ARM9芯片S3C2440为硬件平台,以Linux操作系统为软件平台。首先将USB摄像头采集的视频信息进行处理,然后通过Web服务器网络进行传输,最后用户通过浏览器即可对远程视频进行实时的监控。     

基于ARM远程监控系统的设计与实现

选取了ARM9处理器S3C2410作为硬件平台,以嵌入式Linux操作系统作为核心,介绍了硬件平台的搭建,操作系统的选型,V4l2（Video For Linux 2）视频采集的设计;通过USB摄像头采集视频信息、嵌入式处理器对完成数据的压缩、传输以及控制,最终实现了视频监控系统的主要功能。通过测试,视频采集能够满足远程客户实时性要求,与以往的监控系统相比具有成本低、性能稳定、维护简单等优点,满足了对现有监控系统的要求。     

基于Linux的嵌入式网络视频监控系统研究与设计

网络视频监控已经在嵌入式领域得到了发展,但目前视频监控硬件设施比较昂贵,不能普遍使用。本文提出了一种以ARM9处理器为开发硬件平台和嵌入式Linux系统为软件开发环境的新方法,采用中星微zc301摄像头作为视频前端采集,利用TCP/IP协议技术实现网络通信。系统内部嵌入移植的Web服务器,用户可以通过浏览器进行远端访问。该系统实现了局域网的环境监控,开发成本低,使用方便而且性能高。     

嵌入式无线视频监控系统设计

本嵌入式无线视频监控系统采用高性能ARM9芯片作微处理器,通过嵌入式Linux采集USB摄像头视频数据,并将采集的视频数据帧经JPEG压缩;在ARM9芯片的控制下,通过2.4GHz无线发送/接收模块进行视频数据传输;无线接收端再将视频数据通过网络接口提交给视频应用服务端;最后由视频应用服务端将接收到的压缩数据帧重组、复合成视频图像,实现无线视频监控.     

基于ARM的机器人远程网络视频监控系统

介绍了一种基于嵌入式Linux和ARM微处理器的六足仿生救援减灾机器人嵌入式远程网络视频监控系统。系统以嵌入式Linux和嵌入式微控制器S3C2440为核心平台,利用USB摄像头采集视频信号,采用TCP/IP协议技术进行网络通信,传输采集到的图像画面。使用Web浏览器或其他客户端程序通过PC机接收摄像头传输的画面,实现机器人远程画面的实时监控。     

基于B/S模式的嵌入式视频监控系统的设计

以ARM9处理器S3C2440为核心芯片搭建硬件平台,采用嵌入式Linux操作系统为软件开发平台,设计了一种基于B/S模式的嵌入式视频监控系统的设计方案.通过构建流媒体服务器,完成视频数据的采集、压缩、传输和保存.采用TCP/IP网络协议,移植了Web服务器,开发了Java Applet程序,用户通过浏览器即可对远程视频进行实时监控.系统具有实时性强、体积小、成本低廉、性能稳定、交互性好等特点,具有广泛的应用价值.     

基于嵌入式Linux的视频采集系统设计

针对无线监测系统应用的广泛性,本文提出的视频采集系统是在基于ARM1176JZF-S微处理核心的嵌入式开发平台上实现的,并将视频采集技术与3G无线传输技术相结合,实现基于远程无线视频监控系统。通过实验证明,该方案能够实时流畅地传输640＊480大小的视频图像。     

European Community policy and the market

Abstract This paper starts with some reflections on the policy considerations and priorities which are shaping European Commission (EC) research programmes. Then it attempts to position the current projects which seek to capitalise on information and communications technologies for learning in relation to these priorities and the apparent realities of the marketplace. It concludes that while there are grounds to be optimistic about the contribution EC programmes can make to the efficiency and standard of education and training, they are still too technology driven.     

一种自适应子融合集成多分类器方法

融合集成方法已经广泛应用在模式识别领域,然而一些基分类器实时性能稳定性较差,导致多分类器融合性能差,针对上述问题本文提出了一种新的基于多分类器的子融合集成分类器系统。该方法考虑在度量层融合层次之上通过对各类基多分类器进行动态选择,票数最多的类别作为融合系统中对特征向量识别的类别,构成一种新的自适应子融合集成分类器方法。实验表明,该方法比传统的分类器以及分类融合方法识别准确率明显更高,具有更好的鲁棒性。     

Explanation and prediction: an architecture for default and abductive reasoning

Although there are many arguments that logic is an appropriate tool for artificial intelligence, there has been a perceived problem with the monotonicity of classical logic. This paper elaborates on the idea that reasoning should be viewed as theory formation where logic tells us the consequences of our assumptions. The two activities of predicting what is expected to be true and explaining observations are considered in a simple theory formation framework. Properties of each activity are discussed, along with a number of proposals as to what should be predicted or accepted as reasonable explanations. An architecture is proposed to combine explanation and prediction into one coherent framework. Algorithms used to implement the system as well as examples from a running implementation are given.     

Three Process Perspectives: Organizations, Teams, and People

This paper provides the author's personal views and perspectives on software process improvement. Starting with his first work on technology assessment in IBM over 20 years ago, Watts Humphrey describes the process improvement work he has been directly involved in. This includes the development of the early process assessment methods, the original design of the CMM, and the introduction of the Personal Software Process (PSP)^SM and Team Software Process (TSP){^SM}. In addition to describing the original motivation for this work, the author also reviews many of the problems he and his associates encountered and why they solved them the way they did. He also comments on the outstanding issues and likely directions for future work. Finally, this work has built on the experiences and contributions of many people. Mr. Humphrey only describes work that he was personally involved in and he names many of the key contributors. However, so many people have been involved in this work that a full list of the important participants would be impractical.     

基于复小波噪声方差显著修正的SAR图像去噪

提出了一种基于复小波域统计建模与噪声方差估计显著性修正相结合的合成孔径雷达(Synthetic Aperture Radar,SAR)图像斑点噪声滤波方法。该方法首先通过对数变换将乘性噪声模型转化为加性噪声模型,然后对变换后的图像进行双树复小波变换(Dualtree Complex Wavelet Transform,DCWT),并对复数小波系数的统计分布进行建模。在此先验分布的基础上,通过运用贝叶斯估计方法从含噪系数中恢复原始系数,达到滤除噪声的目的。实验结果表明该方法在去除噪声的同时保留了图像的细节信息,取得了很好的降噪效果。     

How do children do mathematics with LOGO?

Abstract  This paper considers some results of a study designed to investigate the kinds of mathematical activity undertaken by children (aged between 8 and 11) as they learned to program in LOGO. A model of learning modes is proposed, which attempts to describe the ways in which children used and acquired understanding of the programming/mathematical concepts involved. The remainder of the paper is concerned with discussing the validity and limitations of the model, and its implications for further research and curriculum development.     

Editorial: Special issue on recent advances in hybrid control theory and applications

正The demands of a rapidly advancing technology for faster and more accurate controllers have always had a strong influence on the progress of automatic control theory.In recent years control problems have been arising with increasing frequency in widely different areas,which cannot be addressed using conventional control techniques.The principal reason for this is the fact that a highly competitive economy is forcing systems to operate in regimes where     

Information for Authors

正Aim The Journals of Zhejiang University-SCIENCE(A/B/C)areedited by the international board of distinguished Chinese andforeign scientists,and are aimed to present the latest devel-opments and achievements in scientific research in China andoverseas to the world’s scientific circles,especially to stimulateand promote academic exchange between Chinese and for-eign scientists everywhere.     

Enhancing a leaf radiative transfer model to estimate concentrations and in vivo specific absorption coefficients of total carotenoids and chlorophylls a and b from single-needle reflectance and transmittance

The relative concentrations of different pigments within a leaf have significant physiological and spectral consequences. Photosynthesis, light use efficiency, mass and energy exchange, and stress response are dependent on relationships among an ensemble of pigments. This ensemble also determines the visible characteristics of a leaf, which can be measured remotely and used to quantify leaf biochemistry and structure. But current remote sensing approaches are limited in their ability to resolve individual pigments. This paper focuses on the incorporation of three pigments—chlorophyll a, chlorophyll b, and total carotenoids—into the LIBERTY leaf radiative transfer model to better understand relationships between leaf biochemical, biophysical, and spectral properties.Pinus ponderosa and Pinus jeffreyi needles were collected from three sites in the California Sierra Nevada. Hemispheric single-leaf visible reflectance and transmittance and concentrations of chlorophylls a and b and total carotenoids of fresh needles were measured. These data were input to the enhanced LIBERTY model to estimate optical and biochemical properties of pine needles. The enhanced model successfully estimated reflectance (RMSE = 0.0255, BIAS = 0.00477, RMS%E = 16.7%), had variable success estimating transmittance (RMSE = 0.0442, BIAS = 0.0294, RMS%E = 181%), and generated very good estimates of carotenoid concentrations (RMSE = 2.48 µg/cm², BIAS = 0.143 µg/cm², RMS%E = 20.4%), good estimates of chlorophyll a concentrations (RMSE = 10.7 µg/cm², BIAS = − 0.992 µg/cm², RMS%E = 21.1%), and fair estimates of chlorophyll b concentrations (RMSE = 7.49 µg/cm², BIAS = − 2.12 µg/cm², RMS%E = 43.7%). Overall root mean squared errors of reflectance, transmittance, and pigment concentration estimates were lower for the three-pigment model than for the single-pigment model. The algorithm to estimate three in vivo specific absorption coefficients is robust, although estimated values are distorted by inconsistencies in model biophysics. The capacity to invert the model from single-leaf reflectance and transmittance was added to the model so it could be coupled with vegetation canopy models to estimate canopy biochemistry from remotely sensed data.     

Mr. Twinn’s bombes

This article discusses the history and design of the special versions of the bombe key-finding machines used by Britain’s Government Code & Cypher School (GC&CS) during World War II to attack the Enigma traffic of the Abwehr (the German military intelligence service). These special bombes were based on the design of their more numerous counterparts used against the traffic of the German armed services, but differed from them in important ways that highlight the adaptability of the British bombe design, and the power and flexibility of the diagonal board. Also discussed are the changes in the Abwehr indicating system that drove the development of these machines, the ingenious ways in which they were used, and some related developments involving the bombes used by the U.S. Navy’s cryptanalytic unit (OP-20-G).