DSP在天线平台控制系统中的应用

合成孔径雷达要得到高分辨率的成像,必须保证天线波束指向恒定.本文以DSP为核心构造天线平台数字控制系统来对大气扰动造成的雷达载体的角运动进行补偿,当雷达载体在方位向、横滚向及俯仰向发生角运动时,天线平台数字控制系统控制平台向相反方向转动,从而保证天线指向恒定,得到高分辨率的雷达图像.     

DSP在天线平台控制系统中的应用

合成孔径雷达要得到高分辨率的成像,必须保证天线波束指向恒定。本文以DSP为核心构造天线平台数字控制系统来对大气扰动造成的雷达载体的角运动进行补偿,当雷达载体在方位向、横滚向及俯仰向发生角运动时,天线平台数字控制系统控制平台向相反方向转动,从而保证天线指向恒定,得到高分辨率的雷达图像。     

基于DSP平台高性能控制系统与方法研究

基于DSP平台的高性能控制系统由DSP主控板,电机驱动电路板和电源板三个主要部分组成.文中详细说明了系统结构图,叙述了数字输入数字输出电路的组成,给出了模拟输入电路设计原理以及模拟量输入通道控制电路图.在基于DSP的控制系统设计中考虑了故障处理电路.故障处理电路包括过流保护电路和三相不平衡保护电路.阐述了光电编码器接口电路设计思想和接口电路图.实现了对于给定转速的电机运行状态显示.解决了获取转速信息,通过A／D检测电压电流,实现控制算法等关键问题.     

TMS320C6713 DSP的高速EMIF数据接口设计与实现

为减少数字控制系统的延迟时间,针对基于TMS320C6713 DSP的数字控制平台,设计了一种结构简单、易于控制的高速数据接口卡,包含16位、40MHz采样率的A/D转换器以及16位、40MHz刷新率的D/A转换器,通过外部存储器接口EMIF实现DSP开发板与高速数据接口卡的控制信号传输与数据存取,并在CCS编泽平台上编程控制数据的存取以及外部存储器接口EMIF的读写时序;实验结果表明,数字控制系统的延迟时间可低至1.1 μs.     

机载SAR天线稳定平台的DSP数字控制器设计

机载SAR(airborne Synthetic Aperture Radar,合成孔径雷达)中,用三轴稳定平台隔离载机的姿态变化及机械振动来稳定天线波束指向是关键的运动补偿技术之一。本文提出用TMS320LF2407DSP芯片设计机载SAR三轴陀螺稳定平台的数字控制器,介绍了机载SAR对稳定平台的要求和TMS329LF2407DSP芯片用于运动控制器设计的优点,给出了控制系统的原理方框图、数学模型和DSP数字控制器结构图。     

基于DSP的无人机机载天线自动收放系统

根据无人机气动性能与任务设备天线增益的指标要求,文中给出了天线自动收放控制系统的设计与实现,介绍了基于DSP器件TMS320F2812DSP芯片为控制核心的收放系统的硬件组成与软件设计;详细论述了硬件组成中隔离驱动以及外部接口等关键电路设计与实现,提出了电机绕组电流换向、位置控制与速度控制方法,并给出了控制软件流程,解决了天线安装与飞机气动安全的匹配问题;通过无人机飞行搭载实验验证,该系统设计合理,性能稳定可靠,满足了系统指标要求,既保证了天线功率增益,又避免了对飞机的气动性能与飞行安全的影响。     

多天线软件无线电平台中多片AD9238与DSP接口设计

设计了一个应用于多天线软件无线电平台的阵列数据采集系统,重点设计了ADC转换和DSP之间通过EMIF总线进行数据传输的接口电路。提出了一种类似数字复用技术的共享总线,采用同步转换、分时读取的多路AD信号与FIFO存储接口机制,取得良好的数据传输效率。     

DSP与SED1335的接口设计及控制实现

DSP是一种高性能的数字信号处理器,具有快速的计算能力和强大的信息处理能力。针对液晶显示控制系统中遇到的大量实时数据的高速传输问题,文中介绍了一种基于高速DSP控制液晶显示的方法。首先介绍了TMS320F240DSP的主要特点及SED1335液晶显示控制器的原理与使用,然后在此基础上讨论了DSP与液晶显示屏之间采用数字I/O口模拟时序的硬件接口设计方案,给出了具体的软件实现方法,最终实现了DSP与液晶显示控制器SED1335的良好接口,并在实际系统应用中取得了成功。     

DSP与SED1335的接口设计及控制实现

DSP是一种高性能的数字信号处理器,具有快速的计算能力和强大的信息处理能力.针对液晶显示控制系统中遇到的大量实时数据的高速传输问题,文中介绍了一种基于高速DSP控制液晶显示的方法.首先介绍了TMS320F240 DSP的主要特点及SED1335液晶显示控制器的原理与使用,然后在此基础上讨论了DSP与液晶显示屏之间采用数字I/O口模拟时序的硬件接口设计方案,给出了具体的软件实现方法,最终实现了DSP与液晶显示控制器SED1335的良好接口,并在实际系统应用中取得了成功.     

基于CPLD的SJA1000与DSP的接口设计

描述了SJA1000的功能特点,分析了SJA1000的读写时序,讨论了与DSP之间的接口,给出了基于CPLD的软件模拟时序方法,实现TMS320F240对SJA1000的读写访问.该方法可以广泛应用于其他单片机外围器件与DSP的接口设计中.     

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.