基于LuGre摩擦模型的轮胎自振系统数值分析

为用多边形磨损理论研究汽车轮胎磨损,针对最简化的单自由度胎面-路面非线性系统,单独分析胎面侧向自激振动特性与车速的关系. 将LuGre摩擦模型引入胎面-路面单自由度振动系统,模拟轮胎与路面的实际摩擦情况. 利用Matlab仿真胎面在不同车速条件下的振动情况. 结果表明在一定的系统参数设置下,胎面在轮胎宽度方向上能产生硬自激,且车速范围与已知情况基本吻合,从而证明该理论模型正确.     

基于有限元的轮胎自激振动时频分析

研究汽车轮胎减少磨损,延长使用寿命的问题,轮胎多边形磨损与胎面质量块的侧向自激振动密切相关.了解产生自激振动的速度区间以及胎面与地面的摩擦状态就显得十分重要.因此建立了轮胎一地面系统的理论模型,引入符合轮胎橡胶摩擦规律的摩擦曲线.运用有限元软件,建立子轮胎与地面有限元模型,导入上述摩擦曲线,分析了位移时间历程和位移速度相平面图,发现了容易产生自激振动的速度区间.选择三种特征车速进行仿真.结果证明通过研究可以减少轮胎的磨损量,延长寿命,为今后轮胎多边形磨损正确建模有参考价值.     

胎面纠偏控制系统中图像处理技术的应用

介绍了实时胎面纠偏系统的原理和结构.整个系统主要由控制器、控制对象、图像采集和图像处理单元组成,重点对图像处理单元进行研究.根据对胎面图像特点进行的分析,提出了图像处理单元的实现过程和算法分析,包括图像去噪,阈值分割,边缘检测和特征提取,计算偏移角.从提取出的胎面骨架实验结果来看,提取效果比较理想.     

基于图像处理的胎面纠偏控制系统

轮胎生产过程中广泛采用纠偏系统防止半成品胶带发生跑偏。纠偏系统是一个实时或准实时的系统,其性能的好坏主要取决于图像处理模块。本文为了更好地保留图像信息,减少噪声对图像的影响,首先利用小波包对图像的低频和高频部分进行分解;然后,采用Birge-Massart惩罚函数确定的阈值对胎面图像进行有效去噪;接着,利用Robert算子进行边缘检测,提取出胎面边缘和机架边缘;最后,经过算法计算出胎面的偏移角度。     

基于压力和位移传感器的汽车节胎系统

针对大吨位的运输车辆(特别是半挂车)轮胎磨损严重,空载时造成轮胎无谓磨损及耗油等问题,介绍了基于压力和位移双传感器汽车智能节胎系统,通过机电一体化智能节胎的新方法,可以自适应调节汽车在重载时挂车三桥12轮工作,而当空载时挂车均为单桥4轮工作。从而减少了约30%的轮胎磨损,实现节胎、节能、延长车辆的使用寿命和保证安全行车目的。     

基于机器视觉的铣刀磨损测量

针对铣刀磨损人工检测效率不高、稳定性差、检测成本高等缺点,本文提出了一种基于机器视觉技术的铣刀磨损量测量方法。使用工业COMS相机从铣刀端面自动化采集铣刀的图片,应用灰度化、中值滤波、自适应阈值分割等形态学处理方法预处理图像。根据铣刀特征提取其轮廓,使用基于霍夫变换的直线检测、圆检测方法筛选提取铣刀最大磨损区域,经分析,刀刃的最大磨损量为磨损区域最大内切圆直径长度。结果表明,该方法能实现对铣刀刃面磨损快速测量,测量误差较小,满足实际应用需求。     

汽车轮胎号识别中的图像采集

图像采集是汽车胎号识别中的一个首要和重要的环节,介绍了胎号图像采集过程,胎号图像采集中的辅助光源和摄像硬件装置,以及用于调焦、调亮的镜头控制器的设计,最后编程实现胎号图像采集,并将其进行灰度化处理。     

基于B样条曲线的轮胎胎面缠绕算法

为了提高胎面缠绕生产线设备的缠绕质量以及胶条分布的稳定性,降低研发成本和废品率。通过研究工程机械轮胎胎面缠绕机缠绕时胶条的具体缠绕过程,基于B样条曲线理论,提出了胶条缠绕轮胎截面变化情况的算法,对当前的轮胎胎面缠绕过程进行精确的数学描述,实现了对轮胎胎面缠绕过程中轮胎胎面与胶条形状位置的精确控制。实验结果表明:所提方法可以有效提高轮胎胎面缠绕精度,可见所提方法能够增强轮胎生产工艺修改适用性、精确性和稳定性。     

基于机器视觉的轮胎表面缺陷检测系统的研究与应用

在传统的轮胎表面缺陷依靠人工检测,存在劳动强度高、受人的主观影响大以及效率低下的问题。针对这一现象,研究了一种基于机器视觉的轮胎表面缺陷3D检测系统。该系统依靠机器视觉系统获取检测轮胎的表面图像,然后创建3D模型、判定缺陷类型,最终实现实时自动预警,为轮胎生产商提供一种自动化检测方案。系统集成了先进的技术、软件和工具,配套的信息管控系统可以对轮胎型号和生产数据进行采集、存储、分析,以便在生产过程中实现更高效、更可靠的质量控制,具有较高的实际应用推广价值。     

基于小波的人体图像边缘检测的研究及实现

针对人体图像边缘检测的问题,本文从工程应用的角度上分析小波变换的原理,利用Mallat方法对图像信息进行处理.通过C 编程,来实现人体图像的边缘检测.     

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.