一种改进的多机器人协作实时FastSLAM算法

针对FastSLAM1.0中机器人缺乏自身定位测量修正引起的累积误差和FastSLAM2.0引入测量修正引起算法复杂度增加的问题,提出一种改进的基于辅助测量的多机器人协作实时FastSLAM算法,使用双机器人协同工作,领头机器人负责完成同时定位与地图构建任务,辅助机器人通过静态相对位置测量为领头机器人提供实时定位测量修正.该辅助测量方法不仅为SLAM任务执行机器人提供较准确的定位测量值,同时也避免了FastSLAM2.0算法中额外的算法复杂度问题.实验结果表明算法既可以获得较高的精度,而且方便可行,具有较高实用价值.     

基于RFID的蛛网模型定位算法设计

针对当前室内定位算法所遇到的精度问题,在LANDMARC系统的基础上提出了一种基于有源RFID的蛛网定位算法。文中介绍了蛛网模型的建立,详细阐述了蛛网定位系统的定位原理以及算法的实现,并通过仿真实验对蛛网定位算法的误差进行了分析,论证了该算法的可行性和精确性。     

基于虚拟标签与循环校验的RFID定位算法

目前在室内定位中,RFID是一种被广泛使用的技术。本文详细研究了使用主动标签进行室内定位的相关技术与算法,同时在LANDMARC算法的基础上,提出了一种改进的定位算法,并引入了一种称为循环校验的校正机制来提高定位的精确率。最后,通过实验数据可以看出,该算法大大提高了定位的精确度。     

移动机器人在未知环境下的同步定位与地图重建方法

在标准FastSLAM中,随着重采样次数的增加会出现十分严重的粒子退化现象,从而导致机器人位姿估计的一致性很差.针对FastSLAM算法的这一缺陷,提出一种改进的FastSLAM算法.此算法在标准FastSLAM的重采样条件判断中,额外考虑了粒子权重协方差和每个粒子的测量残余一致性,并且使用指数等级选择算法进行新粒子的生成.通过仿真实验可以看出,改进的FastSLAM算法不但可以明显地提高机器人位姿估计的一致性,而且能够很好地保持粒子多样性.     

基于LANDMARC定位算法复杂度的分区算法改进

本文重点讨论研究了基于RFID的LANDMARC室内定位系统,然后在此基础上总结了原LANDMARC系统的不足,并针对LANDMARC系统中的算法复杂度进行分析,提出了一种分区算法来减小系统算法的复杂度.实验结果表明,相比原系统算法,改进后的算法在提高系统定位精度和定位性能的前提下,减小了算法总体的复杂度.     

非视距环境下室内RFID标签定位算法研究

在室内无线定位中,由于受到非视距NLOS的影响,信号的传播变得复杂起来。复杂的传播环境使得传统的定位算法例如最小二乘算法(LS)或者CHAN算法无法达到我们需要的精度。在使用无源超高频无线射频识别(Passive UHF RFID)技术的基础上,分析和建立了UHF RFID信道模型,并由此对定位误差进行了分析。基于运用相位法POA进行测距而得到的距离信息,提出了一种两步式标签定位算法:首先使用凸优化中的内点法将非视距误差消除,再使用加权残差方法进行精确定位。通过仿真结果的比较,表明本文提出的算法优于传统算法。     

基于WiFi的电子标签定位算法

设计了一套以WiFi技术和RFID定位技术为基础的定位系统,简单介绍无线WiFi网络的优势及系统的硬件部分。在算法方面详细描述了LANDMARC算法和三边定位算法,对两种算法的优缺点进行分析,并结合两种算法提出一种新的算法。并在某公司楼道中进行实验,结果表明该定位算法取得了在2m范围内的准确定位。     

射频识别技术及其在室内定位中的应用

在分析射频识别(RFID)基本原理和特点基础上,重点讨论了基于RFID的LARNDMARC室内定位系统,然后在此基础上提出了一种最近邻居改进算法和基于误差多级处理的数据融合定位方法。仿真结果表明,改进后的最近邻居算法比已有的最近邻居算法的定位精度更好。     

基于RFID有源标签的内河船舶定位系统

船舶定位在内河港口与航道管理及船舶运营管理中具有非常重要的作用,对于船公司、租家可监控船舶实时动态,便于管理,应对突发事件,对于港口机关,实现港区全部监控,安排作业计划提高工作效率,保证港区安全。文中利用主动式RFID技术结合相关RFID定位算法实现了内河船舶定位,并提出了一种基于RFID有源标签的内河船舶定位系统标签部署模型,分别讨论和分析了在考虑定位标签正常和具有一定容错能力情况下的标签部署方案和约束要求。结合标签部署模型和定位算法可满足内河船舶定位的基本要求并实现内河船舶的定位。     

FastSLAM算法的仿生优化改进研究

针对机器人导航标准的快速同步定位与地图构建算法(FastSLAM)在重采样过程中存在采样粒子集的贫化以及粒子多样性的缺失导致机器人的定位与建图的精度下降的问题,提出一种基于改进的蝴蝶算法来优化FastSLAM中的粒子滤波部分。改进的算法将机器人的最新时刻的观测和状态信息融入到蝴蝶算法的香味公式中,并在蝴蝶位置更新的过程加入自适应香味半径和自适应蝴蝶飞行调整步长因子,来减少算法的运算时间以及提高预测精度,同时引入偏差修正指数加权算法对粒子的权值进行优化组合,对组合后部分不稳定的粒子进行分布重采样,保证粒子的多样性。通过仿真验证了该算法在估计精度与稳定性方面优于FastSLAM,因此在移动机器人运动模型的定位与建图中具有较高的定位精度与稳定性。     

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.