一种基于混合神经网络的浮选pH值预测模型

矿物浮选过程中,矿浆pH值作为影响浮选效果的一个重要因素,是实现浮选过程监视及优化控制的一个重要参量。目前的pH值测定仪存在交叉污染、测量滞后等问题,难以获得实时准确的pH值。为使浮选运行在最优状态,在泡沫图像特征提取的基础上,提出一种基于自适应遗传混合神经网络的预测模型,该模型首先利用主元分析(PCA)方法对提取的多个图像特征进行降维,然后采用自适应遗传混合神经网络(AGA-HNN)建立pH值预测模型。最后将该模型应用于浮选现场,预测结果能够实时跟踪实际值,根据预测值实时调整工况条件,改善了浮选效果,提高了浮选效率。     

基于图像特征的锑浮选矿浆pH值预测控制

适宜的矿浆pH值是泡沫浮选高效生产的关键。针对浮选矿浆pH值无法在线检测和控制滞后的问题,提取pH关联泡沫表面敏感特征,建立了基于仿射传播聚类(AP)的多模型最小二乘支持向量机(LSSVM)软测量模型;提出一种基于差分进化(DE)的在线支持向量回归(OSVR)pH值预测控制方法,离线建立和在线校正pH值预测模型,采用DE优化方法求解预测控制决策变量实现pH值实时控制。金锑浮选工业数据表明所提出的控制策略稳定了矿浆pH值,减少了药剂消耗。     

基于机器视觉的矿物浮选pH软测量方法

针对泡沫浮选过程中人工检测矿浆pH值严重滞后以及pH检测仪电极容易积垢导致测量不准等问题,提出基于机器视觉的浮选矿浆pH软测量方法。确定了与矿浆pH值最相关的图像特征泡沫颜色、尺寸和流速;采用减法聚类确定模糊系统的初始结构,并选择变尺度分级混沌方法优化隶属函数和输出权值,最终建立模糊神经网络pH软测量模型。工业实践证明应用该模型在线检测浮选矿浆pH值的可行性。     

基于SIFT特征配准的浮选泡沫移动速度提取与分析

利用尺度不变特征转换(SIFT)特征的优势,将其特征配准引入到泡沫速度特征提取中,解决了泡沫速度特征难以提取的问题.工业浮选现场泡沫速度特征提取结果表明:该方法对仿射变换、光照变化等不敏感;可以准确获取各种浮选状态下泡沫移动速度特征.在对某轻金属浮选厂泡沫视觉特征进行为期半年的观察之后,讨论了浮选泡沫速度特征与浮选指标间的关系,为建立基于机器视觉的浮选优化控制打下基础.     

基于泡沫大小动态分布的浮选生产过程加药量健康状态分析

针对矿物浮选过程泡沫大小分布随着药剂量的改变而动态变化的特点,提出一种基于泡沫大小动态分布特征的具有自学习功能的浮选生产过程加药量健康状态统计模式识别方法.首先,通过泡沫图像分割、气泡尺寸分布核密度估计获得浮选气泡大小的概率密度分布函数,采用无监督的最远邻聚类方法获得典型药剂量添加状态下的气泡尺寸统计分布特征集;然后,采用简单的贝叶斯推理方法获得测试时间段对应的药剂添加健康状态分析识别结果,并根据浮选生产工况状态的动态变化对各典型药剂状态下的气泡大小统计分布特征集进行在线学习修正.实验结果表明,所提出方法能实时获取泡沫尺寸分布的动态变化,实现浮选药剂操作健康状态的自动识别与评价,为进一步实现浮选生产过程的加药量优化控制奠定了基础.     

基于图像处理的浮选过程药剂量控制模型

浮选过程有严重的非线性、强耦合性等问题,目前仍没有精确的数学模型描述浮选状态;通过研究赤铁矿阳离子反浮选控制工艺过程,提出利用图像处理技术提取泡沫图像纹理特征参数,采用粗糙集和LVQ神经网络理论建立控制药剂加入量的数学模型;经过现场应用与仿真对比,基于图像处理的控制模型可以满足浮选控制的要求,较好地解决了浮选过程的自动控制问题,为最终建立可以应用于企业生产的控制系统奠定了基础;采用粗糙集并基于LVQ神经网络理论建立药剂添加量控制模型,基于图像处理的控制模型识别准确度在正常状态下能达到83.3%的准确率,可以满足企业生产的要求。     

浮选浆位仪的设计与应用

针对目前许多液位检测仪器都不能正确测量浮选机内浆体的液位这一问题,研制了浮选浆位仪,它采用导电率法,根据煤浆、矿化泡沫层和空气的导电率不同,得到了三种介质的相界面,从而求得浮选煤浆的液面和泡沫层的厚度。基于浮选浆位仪设计的浮选测控系统,实现了浮选过程的优化控制,通过在淮北选煤厂的现场使用表明,浮选浆位仪能适应浮选生产环境,并能有效地测量浮选机内的浆位;同时浮选控制系统根据其测量结果,对浮选过程进行反馈控制;使浮选生产获得了较高的精煤产率,并降低了浮选药剂用量。     

泡沫图像特征驱动的锑粗选加药控制策略

锑粗选工序的加药控制直接影响精选与扫选的性能.通常由人工观察泡沫手动调节药剂.这种方式,存在控制滞后、主观随意性大、易导致浮选性能不稳定甚至恶化的问题.对此,我们提出一种泡沫图像特征驱动的锑粗选加药控制策略.利用概率支持向量回归方法建立基于锑粗选关键泡沫图像特征与加药量的入矿品位估计模型;在此基础上,采用操作模式匹配方法实现加药量的预设定,快速满足入矿品位类型变化后新的控制要求;并采用基于区间II型模糊系统的加药反馈控制器减小泡沫状态与期望的偏差.工业验证结果表明,该方法能有效代替人工加药并改善了锑浮选性能.     

基于半监督聚类的煤泥浮选泡沫图像分类方法

针对选煤厂煤泥浮选过程加药量依靠人工干预存在主观性、滞后性和粗放性的问题,提出了一种基于半监督聚类的煤泥浮选泡沫图像分类方法。首先,采集已知加药比例与未知加药比例下的煤泥浮选泡沫图像样本,并对泡沫图像进行预处理,提取泡沫的气泡个数、气泡面积、气泡周长等形态特征;然后,对已知加药比例下泡沫图像形态特征样本进行标志,对未知加药比例下泡沫图像形态特征样本不做标志,并将已标志泡沫图像形态特征样本与未标志泡沫图像形态特征样本进行混合;最后,利用基于高斯混合模型的半监督聚类方法对混合样本进行聚类后得到各类簇,将各类簇内已标志泡沫图像形态特征样本的信息映射到未标志泡沫图像形态特征样本。应用结果表明,该方法可为煤泥浮选生产过程加药量调整提供指导,降低了药剂消耗量,提高了选煤厂浮选自动化水平和经济效益。     

锑浮选过程加药量自适应迭代学习控制

针对现有的加药量控制方法需要浮选过程动态模型或是鲁棒性不足的问题, 提出一种基于自适应动态规划 (ADP) 的浮选过程加药量自适应迭代学习控制方法. 首先, 将药剂量控制问题转化为两级优化问题 (问题 1 和问题 2). 其中, 基于前馈控制原理求解问题 1 得出前馈补偿分量以抑制外界扰动. 然后, 采用基于值迭代的 ADP 算法, 求解问题 2 以得到最优反馈增益, 从而设计一个数据驱动的最优加药量控制策略使最终的生产指标 (精矿品位和尾矿品位) 跟踪给定值, 且药剂量消耗最少. 最后, 通过工业生产数据进行仿真验证, 证明所提方法的收敛性和稳定性.     

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.