基于区间特性和变量软约束的模型预测控制算法

针对传统的区间模型预测控制算法的性能指标函数设计复杂, 以及被控变量进入区间后稳态轨迹变化幅度大的缺点, 提出一种区间特性和变量软约束的模型预测控制算法. 该算法仅利用期望输出区间的上下限, 通过预测输出与区间的等式关系构造区间跟踪偏差项, 同时利用预测输出和操作变量的增量二次型构造变量软约束项, 减小区间内的稳态轨迹的变化幅度, 上述两项合称为软约束区间跟踪性能指标项. 以回转窑模型为被控对象进行仿真, 表明了算法的有效性.

     

基于区间放松的冲突化解策略

针对基于约束网络的参数设计冲突提出一种化解策略．首先量化各约束的满足程度；然后构造出反映约束网络冲突严重程度的指标，并采用遗传算法以该指标为优化目标寻找制约产品设计的“瓶颈”变量；最后利用设计参数区间的可扩展性，以最小的设计区间损失争取最佳的产品指标．该方法已应用于某型铁路货车转向架弹性元件的设计过程。     

基于Ising计算树的均值场区间传播算法

基于不完全泛函迭代,设计一个均值场区间传播算法,可给出变量期望界.首先,定义Ising均值场计算树模型来表示Ising均值场迭代计算过程.然后,基于Ising计算树设计均值场区间传播算法,通过在计算树上进行消息区间传播,计算出根变量簇变量期望区间.同时证明在2层计算树上区间传播算法给出的变量期望区间包含期望精确值,即给出变量期望界.最后,通过对比实验验证该算法的有效性和期望界的紧致性.     

约束满足混合算法求解并行机Job-Shop调度问题

分析并行机Job-Shop调度问题的特点并建立其约束满足优化模型,结合约束满足与变邻域搜索技术设计了一个求解该问题的混合优化算法。该算法采用变量排序方法和值排序方法选择变量并赋值,利用回溯和约束传播消解资源冲突,生成初始可行调度,然后应用局部搜索技术增强收敛性,并通过结合问题特点设计的邻域结构的多样性提高求解质量。数据实验表明,提出的算法与其他两种算法相比,具有一定的可行性和有效性。     

参考轨迹在线优化的区间预测控制

实际生产过程控制中,特别是多变量耦合的复杂过程中,对某些被控变量其实并没有苛刻的给定值要求,只是满足在给定区间内即可,从而保证整个生产过程控制的平稳.针对这一问题,提出一种基于模型预测控制理论的区间控制算法.该算法对预测控制的优化性能指标进行改进,将性能优化指标中的参考轨迹作为约束变量进行在线优化处理;参考轨迹自动跟踪被控变量输出,使预测控制针对输出在不同的区域范围采取不同的控制强度,从而在实现区间控制的前提下满足平稳控制要求.最后以Shell公司的典型重油分馏塔控制问题为例进行仿真,验证算法的有效性和可行性.     

参考轨迹在线优化的区间预测控制

实际生产过程控制中,特别是多变量耦合的复杂过程中,对某些被控变量其实并没有苛刻的给定值要求,只是满足在给定区间内即可,从而保证整个生产过程控制的平稳.针对这一问题,提出一种基于模型预测控制理论的区间控制算法.该算法对预测控制的优化性能指标进行改进,将性能优化指标中的参考轨迹作为约束变量进行在线优化处理;参考轨迹自动跟踪被控变量输出,使预测控制针对输出在不同的区域范围采取不同的控制强度,从而在实现区间控制的前提下满足平稳控制要求.最后以Shell公司的典型重油分馏塔控制问题为例进行仿真,验证算法的有效性和可行性.     

机床产品分布式协同约束模型研究

研究了机床产品协同开发中约束的种类和特点以及约束模型的建立方法,描述了约束网络的一致性、有效性、完备性和全面性等特性,并列举了一个具体的约束网络实例。建立了协同产品开发中的动态约束模型,将约束分为耦合约束和独立约束两种类型,通过设定耦合约束的变量的取值范围,将耦合约束转换为独立约束,并综合利用约束传播算法和区间求解算法对该约束模型进行求解。最后给出了协同产品开发中约束模型的网络实现流程并开发了相应的原型系统,为冲突的检测方法提供了量化手段,可以提前发现潜在的冲突。     

区间不确定性需求下的D-LFLP模型及算法

考虑物流网络需求的不确定性,运用区间分析理念以区间数度量不确定性变量与参数,建立区间需求模式下的物流网络设计的混合整数规划模型,定义风险系数与最大约束偏差,对模型进行目标函数与约束条件的确定性转化,设计问题求解的区间递阶优化遗传算法,对不同情景状态下目标函数的区间最优解与节点决策方案进行运算。算例测试表明该算法可操作性更强,求解结果具有区间最优解与情景决策的优越性。     

基于约束规划的岸桥与集卡集成调度

针对进口集装箱卸船的岸桥与集卡集成调度问题,分别提出混合整数规划(MIP)模型和约束规划(CP)模型,目标是使得卸船完工时间最短,该问题是NP难题。通过OPL语言设计约束规划模型,利用其为调度问题提供的特殊构造,如区间变量、序列变量等进行建模,并采用"扩展操作任务"的概念来定义区间变量以提升求解效率。为评价解的质量,设计一个新的下界求解方法。使用不同规模的实例对约束规划模型和MIP模型进行测试,结果表明,在小规模实例中,CP模型求解性能略差于MIP模型,但对于中大规模实例,MIP模型无法在设定时限内找到解,而CP模型则能以较快的收敛速度得到高质量的解,目标距离下界的差距控制在2.19%~8.28%。     

基于优化算法的冲突仲裁策略

该文提出了一种基于优化算法的冲突仲裁策略。在约束网络支持的并行设计过程中，建立了冲突仲裁的数学模型，设计了反映冲突严重程度的指标，并针对该指标利用基因算法进行优化求解。与以往的冲突解决方法不同，该方法利用设计参数区间的可扩展性，找到了制约设计问题的瓶颈，以最小的设计区间损失争取到最佳设计指标，从而达到有效解决冲突的目的。与约束网络相配合，该方法能够在并行设计的初期就监控设计过程，提早解决冲突以避免后期出现大返工。文中最后利用了转向架的设计实例说明了该方法的有效性。     

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。     

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.