A family of lower- and higher-order transversal linearization techniques in non-linear stochastic engineering dynamics

Sample pathwise numerical integration of noise-driven engineering dynamical systems cannot generally be performed beyond a limited level of accuracy, especially when the noise processes are modelled using (filtered) white noises. Recently, a locally transversal linearization (LTL) strategy has been proposed by the author (Proc Roy Soc London A 2001; 457 :539–566) for direct integration of deterministic and stochastic non-linear dynamical systems. The present effort is focussed on a host of extensions along with detailed theoretical error analyses of the linearization approach, especially as applied to problems in non-linear stochastic engineering dynamics. Thus, to begin with, estimates of local and global error orders in the basic LTL scheme are obtained separately for the displacement and velocity vectors when the system is driven either by a set of additive noises or by an arbitrary combination of (independently evolving) additive and multiplicative noises. Following this, a new family of higher-order LTL schemes is proposed in order to improve upon the basic LTL method and the associated error orders are established. A stepwise implementation of the lower- and higher-order versions of the LTL method, along with certain computational aspects, is also outlined. The proposed schemes are numerically illustrated, to a limited extent, for a single degree-of-freedom (SDOF) and a two degree-of-freedom (TDOF) non-linear engineering systems under additive and/or multiplicative white noise excitations. Copyright © 2004 John Wiley & Sons, Ltd.     

硫酸锆、碳酸锆的性质、应用及生产技术综述

综述了硫酸锆，碳酸锆产品的性质，生产技术及应用，收集整理了国内外部分厂家和公司该产品的化学指标与生产技术；介绍了“分步液相沉淀法”生产工艺，与“一步法”生产工艺相比，其具有流程短，投入少，操作简单，制造成本低等优点。     

环境友好水基润滑添加剂的研究

在脂肪酸分子中引入硼和氮，合成了一种环境友好水基润滑添加剂BNR，并利用红外光谱对其主要官能团进行了表征。通过四球试验机考察了BNR添加剂在水中的抗磨性能与极压性能，用X射线光电子能谱仪对磨痕表面元素进行了分析，探讨了该类添加剂的极压抗磨作用机理。结果表明：硼氮化水基润滑添加剂BNR在水中具有优良的抗磨和减摩性能；其润滑作用机理是由于长链脂肪酸分子的载体作用、硼的缺电子性、氮的高反应活性以及三者的协同作用与摩擦金属表面形成了一层高强度的吸附膜和／或摩擦化学反应膜。     

制造业跟踪系统解决方案剖析

NetLinx技术的发展，使得跟踪系统发生了划时代的飞跃，在制造业上的应用更加广泛。本文以一间显像管厂为例，详细介绍了跟踪系统在制造业上的应用。     

激光武器对抗效能指标体系研究

武器系统的效能是规划、研制、配置和部署武器系统的基本依据,是评价武器系统优劣最重要的综合性指标,建立正确的效能指标体系是进行效能分析与评价的前提。在详细研究了激光武器对抗机理、效能指标选用原则的基础上,构建了相对完整的激光武器对抗效能指标体系结构,并提出了在不同作战任务下量度激光武器对抗能力的效能定义。     

Effect of Y2O3, CeO2 on Sintering Properties of Si3N4 Ceramics

The effect of rare earth oxides Y203 or Ce02 on sintering properties of Si3N4 ceramics was studied and the mechanism of assisting action during sintering was analyzed. The results in dicate that the best sintering properties appear in Si3N4 ceramics with 5% Y203 or 8% CeO2. Secondary crystallites are formed at grain boundaries after heat treatment,which decreases the amount of glass phase and contributes to the improvement of high-temperature mechanical properties of silicon nitride.     

Modelling and analysis of 3-D arrangements of particles by point processes with examples of application to biological data obtained by confocal scanning light microscopy

Within the concept of point processes, a review is presented of quantities which can be used in studies of three-dimensional (3-D) aggregates of particles. Suitable characteristics and estimators are given for both unmarked and marked point processes. To demonstrate the feasibility of such quantitative approaches, an application in histology, dealing with 3-D arrangements of cell nuclei in rat liver, is described. Using a confocal scanning light microscope, 3-D images are recorded and image analysis used to obtain the coordinates of the centroid, together with the volume and DNA content, of each cell nucleus. Examples of results are given, using both unmarked and marked point processes. In the latter case, cell type, nuclear volume and ploidy group are suitable marks.     

激光平网雕刻机设计

研制了用于制作平面网版的激光雕刻机，设计了雕刻机用CO2激光器、光路系统及单片机控制系统，探讨了将图像文件转化为控制命令文件的方法。     

采用模数转换技术提高脉冲激光测距的测时精度

针对脉冲激光测距中计数量化误差影响测时精度的问题,本文提出了采用模数转换技术提高测时精度的方法,并进行了可行性与精度分析,理论与实践结果均表明,该方法易于实现,能够容易地将计数量化误差减少若干个数量级。     

A new FMS architecture based upon networked DSP servo technology

This paper presents a critical evaluation of existing FMS architectures and the academic and industrial design and development strategies used during their formulation. The paper seeks to address the need for, and value of, existing architectures within the industrial arena. More importantly however, this paper puts forward a new two-tier distributed control architecture for FMS based upon new (real-time) networkable DSP servo control methodologies developed by one of the authors for Softronics in Australia. The ramifications of these methodologies are substantial, not only in terms of FMS control, but in the overall simplification of such systems and the development of flexible fixturing devices over the coming decade. This paper also postulates on how new FMS architectures can be developed from such technologies and details why such architectures could be more appropriate to industry needs than those that are currently in existence.