基于条块拼接的快速纹理合成

针对离线纹理合成算法所生成纹理占用较多存储空间的问题,提出一种所生成纹理可紧凑保存的快速纹理合成算法.该算法相继沿垂直和水平方向以条块拼接的方式合成纹理,合成结果可表示为一系列切割路径的组合,仅需保存这些切割路径即可在渲染时实时重建出纹理图像.通过在预处理中计算得到一组误差小的平行切割路径,合成时无需进行匹配,使得合成速度大幅提高.该算法对于在水平和垂直方向具有自相似性的纹理具有较高的合成质量.     

医学图像3维重建模型的虚拟剖切算法

对医学图像体数据及重构几何模型进行虚拟剖切,可以方便地看到内部的组织,便于观察和诊断,可用于医疗放射治疗规划.针对医学图像重建的表面几何模型,提出了对模型进行平面剖切、立体开窗及任意交互切割的算法.平面剖切和开窗是用剖切面或剖切体对重建模型施以剖切,在剖切面上生成边序列及顶点序列;由此边序列和顶点序列生成封闭的边界轮廓,确定各轮廓的包含关系;对封闭轮廓包围的截面区域进行Delaunay三角剖分,得到完整的剖切后的表面模型.任意交互切割过程是交互生成切割路径,确定切割边界,并沿切割边界对表面模型进行切割.实验结果证明了本文算法的有效性.采用本文算法可得到良好的虚拟剖切效果.     

模型驱动的嵌入式系统测试脚本生成方法研究与实现

自动化测试通过机器运行事先准备好的测试脚本进行测试，提升了软件测试效率。然而，测试脚本存在着编写专业性强、调试工作量大、维护成本高、难以复用等问题，成为自动化测试技术难以广泛使用的主要技术瓶颈。以嵌入式系统为测试对象，提出了模型驱动的测试脚本生成方法。该方法根据BPMN2.0建模标准对测试业务流程进行可视化建模；采用路径深度覆盖算法生成测试路径，根据路径上的约束条件生成测试输入参数；通过自定义的测试动作原语将测试路径和输入参数转化为可在嵌入式系统测试平台ETest上自动执行的测试脚本。实现的原型系统支持嵌入式系统的配置项级和系统级的测试脚本生成，提高了测试工具的易用性和测试模型及脚本的可理解性、可复用性和可维护性。     

基于时间自动机的CTCS-3级列控等级转换场景测试用例生成方法研究

为了提高列控等级转换系统测试效率和自动化程度,以时间自动机为基本依据,研究设计了一种中国列车运行控制系统-2级转中国列车运行控制系统-3级列控等级转换系统进行模型信息提取,并自动生成测试路径,从而生成具体的测试用例。结果表明,列车转换时间主要集中在62 s～75 s。转换时间为80 s时,转换成功概率为99.7%以上。等级转换过程,结合获得的测试路径,最终得到测试用例153条。在测试路径基础上,依据逻辑覆盖准则,得到各谓词条件的变量取值范围,结合已有测试路径,最终生成了具体测试用例。该方法的测试用例有效提高了软件开发效率,缩短开发周期,降低了出错率,提高测试自动化程度。该方法提高了列控等级转换系统测试效率和自动化程度,对列控系统等级转换场景软件开发高效性研究具有重要意义。     

面向云测试的并行测试用例自动生成方法

为实现云计算环境下的高效软件测试,提出一种Web 应用系统功能测试的并行测试用例自动生成方法。该方法首先根据场景流图采用深度优先遍历算法生成并行测试路径,录制组合产生并行测试脚本,并进行参数化处理;然后,使用基于搜索的软件测试(SBST)方法自动生成可经过目标路径的有效测试数据集,脚本与数据耦合形成大量可并行部署的自动化测试用例。为验证方法的有效性设计了自动化云测试原型系统。实验结果表明,该并行测试用例自动生成方法可以高效地为云平台提供测试用例输入,提高测试效率。     

基于模型预测控制的飞机蒙皮铣削方法研究

针对飞机蒙皮铣削精度低的问题,提出一种考虑铣削力的模型预测控制铣削方法。首先,构建以机械臂为工具的自动化铣削系统,利用矢量法推导机械臂正反解运动学模型。其次,提取飞机蒙皮三维轮廓,采用离散法进行曲线偏移,规划铣削加工路径;在此基础上,利用五阶B样条曲线拟合路径得到加工轨迹。然后,建立铣刀与工件接触数学模型,以铣削力与速度比、轨迹误差与控制输入为目标函数,采用预测模型反馈校正控制跟踪轨迹。最后,利用激光跟踪仪测量蒙皮修切精度。修切的重复定位精度与绝对定位精度分别在±0.1 mm和±0.3 mm以内。相较于传统基于激光跟踪仪测量的铣削方法,采用本方法可获得到较高的铣削加工精度。该方法可用于机器人铣削加工以及其他自动化加工任务。     

OCR切割性能自动评测

针对OCR(Optical Character Recognition光学字符识别)切割性能的评测问题,提出了一种基于切割图的评测方法,设计并实现了一个用于性能评测的自动化系统.该系统采用南开大学机器智能研究所自行研发的OCR图像切割处理核心RTK( Recognition Tool Kits识别工具包),根据切割样张集Cut-Set,计算切割错误统计数据、输出切割效果图像并对RTK进行修改.实验结果表明该评测方法显著提高了评测效率.     

基于W型网络的乳腺动态对比度增强磁共振图像合成

动态对比增强核磁共振成像已被广泛应用于乳腺癌等恶性肿瘤的临床诊断,但是对造影剂过敏患者将无法进行该项检查,提出一种融合边界及区域信息的增强图像生成网络用于生成乳腺虚拟动态增强MRI图像。该网络由一条下采样路径和两条对称的上采样路径组成,使用跳跃连接将下采样路径的低维特征图直接传递到上采样路径上,同时在两条上采样路径间也实现边界与区域特征图的传递。实验结果表明,该方法能够安全、高效及低费用地实现乳腺虚拟动态增强MRI图像合成。     

婴幼儿视网膜广域成像系统

为实现婴幼儿眼底疾病的及时诊断与治疗,开发的婴幼儿视网膜广域成像系统可以解决成像时大视场要求.系统包括照明部分、成像部分和图像采集装置.设计了角膜接触眼底镜,采用像差小、折射率大的非球面设计,满足大视场的要求;设计了图像采集装置,使用C++编写图像采集处理软件,进行图像采集、相机标定和几何畸变校正.实验结果表明：采用多环光纤光线照明的婴幼儿视网膜广域成像系统可以实现85°视场的较清晰广域成像;采用基于相机标定的图像几何畸变校正方法,可有效补偿视网膜成像光路的畸变.该婴幼儿视网膜广域成像系统可以为眼科疾病的诊断、筛查提供客观、清晰的依据.     

基于点云的补漆机器人系统

汽车补漆机器人需要面对各种不同大小的车型,适配各种造型曲面和颜色,这种高度自适应要求使得补漆机器人在目标跟踪、路径规划、运动空间等方面的设计难度远超汽车厂的喷漆机器人.因此需要重新规划喷漆路径,首先对汽车的点云数据进行分部位切割,然后以八邻域法计算封闭曲面轮廓,最后以切片法在曲面上生成光栅轨迹,形成了每一个补漆面的关键路径.设计了八轴桁架机器人系统,用蚁群算法计算生成八轴联动时的路径规划,再通过倍福的ADS协议将路径数据和梯形曲线的加速度下发到PLC运动控制程序,完成各关节轴的联动协同补漆运动.实测表明,该系统能针对不同汽车,自动控制机器人工具轴心以法向量对准任意曲面,并以联动方式驱动八轴平稳跟踪曲面运动.该系统可广泛应用于各种曲面的机器人加工.     

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.