非线性拟合法测定电化学合成二茂铁的电极过程动力学参数

用非线性拟合法计算得到电化学合成二茂铁中铁阳极的电极过程动力学参数 ,并与传统的三点法 ,线性极化法得到的结果进行了比较 ,讨论了各种方法的相对误差。     

Matlab在乙醇胺反应动力学方程回归和预测中的运用

乙醇胺反应包括生成一乙醇胺(MEA)、二乙醇胺(DEA)和三乙醇胺(TEA)三种反应,其动力学方程参数回归涉及多个变量.本文采用Matlab编程,用线性拟合求解MEA生成反应活化能和指前因子,用非线性最小二乘拟合求解DEA和TEA反应的动力学常数,从而得到整个乙醇胺反应的动力学方程,并通过积分动力学方程,得反应物浓度与时间的关系,与试验数据符合较好,说明采用Matlab处理复杂实验数具有优越性.     

基于粒子群-信赖域的金属极化曲线拟合算法

根据大气环境下腐蚀金属的极化行为特征,选择与之相适应的极化曲线方程,方程中包含7个电化学腐蚀动力学参数,如何求得高精度的参数至关重要。极化曲线拟合属于非线性最小二乘问题,而传统的非线性拟合方法来解决曲线拟合问题时有相当明显的缺陷,例如过分依赖参数初始值、拟合精度不高和结果陷入局部最优问题。对此提出基于粒子群-信赖域的极化曲线拟合算法来求得动力学参数,并通过实验证明该方法的有效性和鲁棒性。     

用MATLAB工具箱拟合生化非线性动力学模型

非线性动力学模型参数回归难度大,常转化为线性模型间接估算,这样违反了统计分析的某些规则,所得参数偏差大。文中结合实例,对比传统方法和MATLAB回归分析工具箱nlintool函数。结果表明,用MATLAB回归分析工具箱计算准确、方法简单,并能显示直观的拟合曲线图。     

基于改进非线性单纯形的群体药代动力学数据拟合研究与实现

指出了NONMEM所用算法的不足之处,介绍了单纯形法原理及通过改进的方法来解决该问题.通过应用改进的非线性单纯形法对群体药代动力学核心拟合算法进行了研究与改进,使用Matlab编写其核心拟合程序.结果表明,使用改进单纯形法来拟合实测数据可大大提高计算群体药代动力学参数的速度及精度,以便于更好地构造群体药代动力学群体模型.     

几种土壤氟吸附动力学研究

采用平衡法对我国几种土壤氟吸附的动力学过程进行了研究。结果表明,不同土壤氟吸附的动力学参数差异很大,黄壤的最大吸附量最高,棕壤最低,棕壤的平衡时间最短,石灰土的平衡时间最长。不同土壤的氟吸附动力学参数与土壤理化性质有很大相关性。供试土壤的氟吸附动力学过程用双常数方程和E lovich方程描述获得了良好的拟合效果。而一级动力学方程和二级动力学方程都不适合土壤氟吸附动力学过程的描述。不同土壤的k值和β值证明黄壤较其他土壤吸附速率大,对加入土壤中氟的缓冲性大。     

如何用OpenLu解方程

解方程(组)是工程计算、数值计算中很普遍的现象。人们用计算机求解,大大提高了工作效率。解方程(组)有符号求解和数值求解两种。工程中遇到的方程大多没有符号解,而只有数值解,故数值求解是更广泛应用的方法。下文仅讨论方程(组)的数值求解。目前,Matlab、Mathematica、Maple等数学软件都具有强大的解方程能力,但普遍存在的问题是:(1)需要初值,这是令人十分头痛是问题。(2)在需要获得方程(组)全部解时,需要复杂的编程实现。推荐使用OpenLu求解方程(组)。OpenLu是国产软件,绿色免安装,体积小巧而又不失功能强大,在解方程方面尤     

微生物发酵动力学模型及其参数拟合的软件实现

发酵动力学主要研究发酵过程中菌体生长、产物合成和底物消耗之间的关系,对发酵过程的调控及发酵规模的放大都有着重要的指导意义.目前微生物发酵动力学一般由菌体生长动力学、产物生成动力学和底物消耗动力学三部分组成,但是其模型绝大多数都是非线性,参数拟合难度大.目前常用的估算方法有线性转化拟合、非线性拟合和遗传算法拟合法.本文首先总结目前国内外分批发酵中常用的数学模型及其表达式,然后通过实例并结合软件编程详细的介绍了这3种方法的软件实现方法,并且比较3种方法拟合效果.结果表明线性转化法拟合误差较大,非线性和遗传算法拟合效果较好,但遗传算法能以较大概率逼近全局最优,而非线性拟合法则容易陷入局部最优.     

用粒子群优化算法重构超二次曲面三维模型

针对在三维重构过程中用L—M（Levenberg—Marquardt）方法求解超二次曲面参数拟合问题的不足，提出了用粒子群优化算法来进行超二次曲面参数拟合的新方法．本文详细阐述了超二次曲面的三维表示特性，L—M算法拟合超二次曲面参数模型的分析，以及用粒子群优化算法拟合超二次曲面参数模型的原理、实现方法和实验结果．用粒子群优化算法对超二次曲面进行参数拟合，克服了L—M方法的缺陷，取了满意的效果．     

乙苯脱氢反应器的动态建模与分析

建立了乙苯脱氢反应器的一维拟均相动态模型来模拟实际反应器。以实际工厂数据为基础,用差分进化算法拟合出了反应动力学模型参数和催化剂失活模型参数。模拟结果表明建立的反应器模型精度较高适合于工业应用。同时考虑到实际的开车过程耗时较长,文中设计了一种反应器开车方案,并通过计算机模拟验证了该方案的可行性。     

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.