基于强跟踪滤波器的多目标跟踪方法

在诸多的多目标跟踪算法中，相互作用多模型（IMM）算法是目前公认的最为有效的算法。但到目前为止，LMM估计方法都是建立在卡尔曼滤波器（KF）和扩展卡尔曼滤波器（EKF）基础上，因而其性能不仅依赖于所采用的模型集，而且在更大程度上依赖于所采用的滤波技术。强跟踪滤波器（STF）克服了卡尔曼和扩展卡尔曼的三大缺陷，因而设计一种基于STF的IMM目标跟踪算法显然能提高其性能。仿真实验表明，基于STF的IMM算法的跟踪性能要优于基于KF和EKF的IMM算法的跟踪性能。     

基于无极卡尔曼滤波算法的雅可比矩阵估计

在基于图像的机器人视觉伺服中,采用在线估计图像雅可比的方法,不需事先知道系统的精确模型,可以避免复杂的系统标定过程。为了有效改善图像雅可比矩阵的在线估计精度,进而提高机器人的跟踪精度,针对机器人跟踪运动目标的应用背景,提出了利用无极卡尔曼滤波算法在线估计总雅可比矩阵。在二自由度的机器人视觉伺服仿真平台上,分别用卡尔曼滤波器（KF）、粒子滤波器（PF）和无极卡尔曼滤波器（UKF）三种算法进行总雅可比矩阵的在线估计。实验结果证明,使用UKF算法的跟踪精度优于其他两种算法,时间耗费仅次于KF算法。     

用于弹道目标跟踪的新的非线性滤波算法

针对再入阶段弹道目标的跟踪问题,提出一种新的自适应滤波算法,即强跟踪有限差分扩展卡尔曼滤波（STFDEKF）算法,用于非线性系统的目标跟踪。该方法使用Sterling内插公式进行多项式的近似,从而实现对非线性函数的近似,避免了非线性函数的求导运算;并且算法中引入强跟踪的因子来修正先验的协方差矩阵。新算法改进了跟踪精度,扩大了应用范围,增强了滤波收敛性。仿真实验将新算法与扩展卡尔曼滤波器（EKF）、有限差分扩展卡尔曼滤波器（FDEKF）进行了比较,结果表明,STFDEKF在跟踪精度和滤波可靠性上均优于EKF和FDEKF,但其计算复杂性更大。得出结论,STFDEKF是个很有效的非线性滤波算法。     

一种稳健的移动机器人目标跟踪算法

为了有效地实现复杂环境下机器人运动目标跟踪,提出了一种结合卡尔曼滤波和均值漂移的目标跟踪算法.该算法首先通过帧间差法在复杂背景中获取目标模型,以机器人自身一个周期的运动作为卡尔曼滤波器的输入量,以卡尔曼滤波器的估计值作为均值漂移算法的启动点,再利用均值漂移算法得到最终目标位置,最后通过目标遮挡判定来解决遮挡问题.实验表...     

基于强跟踪平方根容积卡尔曼滤波的纯方位目标运动分析方法

针对纯方位目标跟踪系统中模型状态简化、系统噪声统计特性未知、目标初始距离信息不准确导致的滤波收敛时间长和滤波精度不高的问题,以自主水下机器人(Autonomous Underwater Vehicle, AUV)跟踪水下动态目标为例,提出了一种基于强跟踪平方根容积卡尔曼滤波器(Strong Tracking Square Root Cubature Kalman Filter, STFSRCKF)的纯方位目标运动分析算法。该算法在滤波过程中,利用平方根容积卡尔曼滤波器(Square Root Cubature Kalman Filter, SRCKF)完成预测更新,对于SRCKF中的每个容积点采用强跟踪滤波器(Strong Tracking Filter, STF)进行更新,设计滤波增益以抑制噪声对系统状态估计的影响,有效提高了滤波的数值稳定性,减小了状态估计误差。通过仿真分析,比较了扩展卡尔曼滤波器(Extended Kalman Filter, EKF)、无迹卡尔曼滤波器(Unscented Kalman Filter, UKF)、平方根容积卡尔曼滤波器(Square-Root Cubature Kalman Filter, SRCKF)、STFSRCKF的算法性能,实验表明所提算法具有跟踪速度快,精度高等优点。     

卡尔曼粒子滤波的视频车辆跟踪算法研究

近年来,视频车辆跟踪作为城市智能交通系统（ITS）的一个关键技术受到关注。本文针对传统粒子滤波的非线性、非高斯性可能导致跟踪过程的不稳健性,提出一种基于卡尔曼粒子滤波的视频车辆跟踪算法,该算法利用基于重要区域的目标颜色直方图统计模型对视频车辆目标进行建模,并将其应用于卡尔曼滤波更新中,通过采用Mean Shift算法将卡尔曼滤波器引用到粒子滤波器当中,对车辆的运行轨迹进行校正,实现了局部线性滤波,实现了在保持跟踪系统整体上的非线性、非高斯性的同时,兼顾其局部的线性高斯特性。实验结果表明,本文所提出的方法与传统粒子滤波方法相比,能够更准确地对车辆进行跟踪,同时保证了在复杂环境下性能的稳健性。     

海上运动目标跟踪系统的设计

为实现对海上运动目标的实时跟踪,克服跟踪效果易受到严重遮挡影响的缺点,建立了一套实时跟踪系统,并且结合目标的运动信息与新的模型更新策略,对均值漂移与卡尔曼滤波器相结合的跟踪算法做出了改进.当运动船只被遮挡的比例较大时,先用估计出的目标速度矢量更新卡尔曼滤波器,并用相应的模型更新策略更新目标模型以提高模型相似性度量的精确性,再单独利用滤波器进行跟踪,取得了较好的跟踪效果.实验结果表明,该系统可以较好地实现海上运动目标的跟踪,并且改进后的算法具有良好的实时性和鲁棒性.     

AR预测模型的IMM跟踪算法

针对LOS/NLOS混合条件下对机动目标的鲁棒跟踪问题,提出一种基于AR预测模型的交互式多模型（Interacting Multiple Model,IMM）跟踪算法（ARIMM）。该算法利用AR预测模型对运动状态建模,针对LOS与NLOS条件下观测噪声的分布不同分别使用无迹卡尔曼滤波器（Unscented Kalman Filter,UKF）和改进的无迹卡尔曼滤波器（Robust Unscented Kalman Filter,RUKF）,通过IMM方法估计出移动台的位置,利用该位置更新AR模型的参数,使AR模型与真实运动状态更加匹配,实现精确跟踪。仿真结果表明,在LOS/NLOS混合条件下,与传统的UKF和RUKF算法相比,该算法对机动目标跟踪的鲁棒性更好。     

基于IMM-UKF的纯方位机动目标跟踪算法

针对在非线性机动目标跟踪中存在的滤波器易发散、跟踪误差大等问题,本文在多站纯方位跟踪的基础上,把Unscented卡尔曼滤波(Unscented Kalman filter,UKF)引进到交互多模型算法(Interacting multiple model,IMM)中,设计了交互多模型UKF滤波算法,克服了EKF中引入的较大线性化误差对机动目标跟踪算法性能的影响.最后将该算法与扩展卡尔曼滤波(EKF)、IMM-EKF算法进行了比较,仿真结果表明:IMM-UKF 算法增强了EKF滤波器的稳定性,提高了滤波收敛速度和跟踪精度.     

基于PF和UKF的水下目标运动估计方法研究

针对无人水下航行器（UUV）目标跟踪控制需求,分别提出了水下目标的粒子滤波（PF）和无迹卡尔曼滤波（UKF）运动估计方法,建立了目标运动参考坐标系,给出了坐标系之间转换基本方法;设计了建立了目标的典型运动模型和非线性随机运动模型,利用前视声呐实测实验数据,完成水下目标运动估计。通过与扩展卡尔曼滤波器（EKF）的目标运动估计对比仿真实验,验证了PF和UKF两种目标运动估计方法的有效性。     

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。     

煤矿井下安全监控分站的设计及其仿真实现

为了设计一种具有低成本、低功耗、易操作、功能强且可靠性高的煤矿井下安全分站,针对煤矿安全生产实际,文章提出了采用MCS-51系列单片机为核心、具有CAN总线通信接口的煤矿井下安全监控分站的设计方案;首先给出煤矿井下安全监控分站的整体构架设计,然后着重阐述模拟量输入信号处理系统的设计过程,最后说明单片机最小系统及其键盘、显示、报警、通信等各个组成部分的设计;为验证设计方案的可行性与有效性,使用Proteus软件对设计内容进行仿真验证,设计的煤矿井下安全监控分站具有瓦斯、温度等模拟量参数超标报警功能和电机开停、风门开闭等开关量指示功能;仿真结果表明:设计的煤矿井下安全监控分站具有一定的实际应用价值.     

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.     

View-based model-driven architecture for enhancing maintainability of data access services

In modern service-oriented architectures, database access is done by a special type of services, the so-called data access services (DAS). Though, particularly in data-intensive applications, using and developing DAS are very common today, the link between the DAS and their implementation, e.g. a layer of data access objects (DAOs) encapsulating the database queries, still is not sufficiently elaborated, yet. As a result, as the number of DAS grows, finding the desired DAS for reuse and/or associated documentation can become an impossible task. In this paper we focus on bridging this gap between the DAS and their implementation by presenting a view-based, model-driven data access architecture (VMDA) managing models of the DAS, DAOs and database queries in a queryable manner. Our models support tailored views of different stakeholders and are scalable with all types of DAS implementations. In this paper we show that our view-based and model driven architecture approach can enhance software development productivity and maintainability by improving DAS documentation. Moreover, our VMDA opens a wide range of applications such as evaluating DAS usage for DAS performance optimization. Furthermore, we provide tool support and illustrate the applicability of our VMDA in a large-scale case study. Finally, we quantitatively prove that our approach performs with acceptable response times.     

A pragmatic multi-method investigation of discrepant technological events: Coping,attributions, and ‘accidental’ learning

Discrepant technological events or situations that entail a problem, a misunderstanding or a difficulty with the Information Technology (IT) being employed, are common in the workplace, and can lead to frustration and avoidance behaviors. Little is known, however, about how individuals cope with these events. This paper examines these events by using a multi-method pragmatic approach informed by coping theory. The results of two studies – a critical incident study and an experiment – serve to build and test, respectively, a theoretical model that posits that individuals use a variety of strategies when dealing with these events: they experience negative emotions, make external attributions, and adopt engagement coping strategies directed at solving the event, eventually switching to a disengagement coping strategy when they feel they have no control over the situation. Furthermore, users’ efforts may result in ‘accidental’ learning as they try to overcome the discrepant IT events through engagement coping. The paper ends with a discussion of the results in light of existing literature, future opportunities for research, and implications for practice.