CAN总线在石油仪器组合导航系统中的应用

基于DSP + FPGA结构的石油仪器组合导航系统中CAN总线系统设计,为了使数据能够在整个CAN总线网络协调、有效、快速、稳定的传输,提出了一种使用FPGA作为CAN总线节点结构中的核心处理器的设计方法;CAN控制器采用具有SPI接口的MCP2515,利用FPGA实现MCP2515的初始化、数据的发送和接收,实现了DSP处理器的CAN总线扩展应用;该方法由于把CAN节点控制的大量的工作交给FPGA实现,DSP只需要对FPGA中CAN数据接收FIFO和CAN数据发送FIFO进行读写操作,即可完成CAN总线的数据读写操作,大大减轻了DSP的数据处理压力;试验测试及产品应用表明,该设计有效、稳定可靠、可扩展性好,易于修改和移植,具有较强的工程实用价值。     

基于FPGA的RapidIO总线接口设计与实现技术

为了适应新的数字信号处理技术的发展,采用FPGA实现技术设计了串行RapidIO高速串行传输接口,实现了DSP与FPGA之间、FPGA与FPGA之间的高速数据传输,详细介绍了本地端点设备访问和远端设备访问的时序设计过程。对RapidIO总线的性能指标进行了测试,试验表明,在1lane、全双工模式下,数据传输速率可达243MB/S,突破了以前DSP的外部接口总线的传输速度瓶颈。     

高速串行接口在基带系统中的应用研究

现有的LTE-A系统基带部分多采用DSP+FPGA的平台构架。DSP作为主控制器,完成物理层算法及流程控制;FPGA则作为协处理器,负责数据处理和定时。如何快速实现DSP与FPGA间的命令交互以及数据传输成为亟待解决的问题。对类似平台及DSP与FPGA的各种接口进行了研究,提出了采用EMIFA接口负责DSP与FPGA间的命令交互,利用高速串行接口SRIO实现DSP与FPGA间的数据传输的新方案。对该方案进行板级联合调试以及Modelsim SE环境下的仿真。调试与仿真结果表明,该方案具有较高的可行性和通用性。     

基于FPGA的AXI4总线时序设计与实现

针对AXI4总线设备之间的高速数据传输需求,根据AXI4总线协议,设计实现了一种基于FPGA的AXI4总线读写时序控制方法.以FPGA为核心,采用VHDL语言,完成了满足AXI4总线协议的读猝发方式数据传输和写猝发方式数据传输时序控制模块的设计.利用FPGA内部嵌入式系统提供的高性能数据传输接口完成AXI4时序控制模块的功能验证.实际应用表明,依据提出的设计方法实现的读写时序控制模块能够满足AXI4总线协议规定的时序关系,实现数据的高速正确传输,总线数据传输速率能够达到1.09 GB/s.     

CAN总线在核热工测量仪表中的应用

通过CAN总线传输数据及控制命令,其数据传输高速可靠、抗干扰能力强、传输距离远,可低代价的实现探测节点的扩充,并可非常方便地与其它设备或系统共享数据。本文采用CAN总线建立现场众多核仪表之间的联系,并着重介绍了CAN总线热工仪表的总体架构以及主要元器件的选择、电路设计、软件编写等内容。     

基于FPGA FIFO处理的多路CAN总线高速通信设计

船舱监控系统配置多种信号监测设备,需要对各种信号监控设备的交互数据进行实时采集和处理,提出一种基于FPGA FIFO处理单元的多路CAN总线的高速通信设计;采用多路隔离CAN总线通道的设计方法,利用FPGA实现CAN总线数据、地址及控制信号的统一管理,并在FPGA中引入FIFO处理单元,有效扩展CAN总线接收数据的存储深度,规避大量信息的频繁处理对计算机处理系统造成的负担,实现实时操作系统上的高速报文交互;试验测试证明,该设计有效提高多路CAN总线通信的极限速率,合理优化计算机系统中断资源分配方式,降低CAN总线通信的中断频率。     

基于DSP的CAN总线通用的监控系统

以TMS320LF2407控制器的CAN模块为核心,设计了CAN总线节点模块,实现一台PC对多禽謦辅器的监控。给出了实现PC与DSP控制器通信协议转换的软硬件。调试出一台PC对多个DSP控制器的监控,实现了基于DSP的CAN总线监控网络的信息传输。     

基于FPGA的CAN总线通信系统

为了克服单片机固有的缺陷,满足航天控制的需求,文章提出了如何利用FPGA采用查询的方式控制CAN控制器SJA1000,从而实现CAN总线数据通信的方法;介绍了该系统的硬件构成、芯片选择和组成原理,对FPGA的控制程序进行了分析和设计;实验结果表明,系统完全满足CAN总线通信要求,与以往基于单片机的CAN总线通信系统相比较,降低了体积、重量和功耗,具有优越性;该设计已成功应用于星载电场仪的地面检测设备中。     

一种高速PCI数据采集处理系统的设计与实现

针对图像处理中数据采集与处理的现状,介绍了基于DSP和PCI控制器的高速数据的实时采集、存储和处理的方法,并分别对电路原理图的硬件设计和PCI接口的软件设计做了阐述.该系统主要采用了DSP芯片来实现各种数字信号处理的算法程序,PCI总线控制器来实现PCI总线接口,以及CPLD作为控制DSP与PCI之间能够正常进行数据传输的枢纽,从而实现了数据的高速、高精度处理,为图像采集与处理提供了新的方法.     

基于DSP和FPGA的信息化发射平台多协议网关设计

为实现信息化发射平台控制系统不同网段之间互联互通,实现了一种能够对以太网、CAN等不同协议数据进行解析、过滤及转发的多协议网关。该网关采用DSP+FPGA的控制器架构,在FPGA内部通过CAN IP核的方式实现了六路CAN控制器;FPGA内部还实现了一路Microblaze软核,软核上运行lwIP以太网协议栈,实现一路以太网控制器功能。DSP作为控制核心,调用FPGA实现的驱动函数实现以太网和CAN数据收发,并根据特定的转发策略对接收数据进行解析、过滤和转发。试验结果表明,该多协议网关单元具有通信接口种类多、数量多,数据转发实时性强、可靠性高,数据解析、转发规则可编程设定、灵活性高等特点,能够适应不同系统的应用需求。     

Only connect: teaching, technology and telesis

Abstract This paper describes an approach to the design of interactive multimedia materials being developed in a European Community project. The developmental process is seen as a dialogue between technologists and teachers. This dialogue is often problematic because of the differences in training, experience and culture between them. Conditions needed for fruitful dialogue are described and the generic model for learning design used in the project is explained.     

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。     

Avoiding semantic and temporal gaps in developing software intensive systems

Development of software intensive systems (systems) in practice involves a series of self-contained phases for the lifecycle of a system. Semantic and temporal gaps, which occur among phases and among developer disciplines within and across phases, hinder the ongoing development of a system because of the interdependencies among phases and among disciplines. Such gaps are magnified among systems that are developed at different times by different development teams, which may limit reuse of artifacts of systems development and interoperability among the systems. This article discusses such gaps and a systems development process for avoiding them.     

Designing economic np control charts: A programmed simulation approach

This paper presents control charts models and the necessary simulation software for the location of economic values of the control parameters. The simulation program is written in FORTRAN, requires only 10K of main storage, and can run on most mini and micro computers. Two models are presented - one describes the process when it is operating at full capacity and the other when the process is operating under capacity. The models allow the product quality to deteriorate to a further level before an existing out-of-control state is detected, and they can also be used in situations where no prior knowledge exists of the out-of-control causes and the resulting proportion defectives.     

The development of robot art

Going through a few examples of robot artists who are recognized worldwide, we try to analyze the deepest meaning of what is called “robot art” and the related art field definition. We also try to highlight its well-marked borders, such as kinetic sculptures, kinetic art, cyber art, and cyberpunk. A brief excursion into the importance of the context, the message, and its semiotics is also provided, case by case, together with a few hints on the history of this discipline in the light of an artistic perspective. Therefore, the aim of this article is to try to summarize the main characteristics that might classify robot art as a unique and innovative discipline, and to track down some of the principles by which a robotic artifact can or cannot be considered an art piece in terms of social, cultural, and strictly artistic interest. This work was presented in part at the 13th International Symposium on Artificial Life and Robotics, Oita, Japan, January 31–February 2, 2008     

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.