一种新的Presence建模方法

在分析Presence信息特征的基础上,提出了Presence模型的建模需求和功能目标,并指出:信息共享、隐私保护以及信息融合要求对信息提供一致的管理方式,可通过建立Presence信息模型来解决这一问题,信息模型的建立应该直观和易用.根据建模需求对适用的建模方法进行了比较,建立了一种新的面向普通应用开发者的混合建模方法,结合图形化建模和本体建模的优点,在建模过程引入了模型驱动结构(MDA)方法和工程化思想,标准化的表达方式和规范的建模步骤保证了建模的质量.     

基于PDM框架的集成产品建模环境

ＰＤＭ是管理所有产品相关信息和过程的技术,为集成产品设计系统提供了支撑环境。本文描述了ＰＤＭ的概念和功能,介绍了集成产品模型和对集成产品建模环境的要求,提出了ＰＤＭ框架下的集成产品建模环境的框架。     

一种新型物流服务供应链建模方法

提出了一种多目标混合整数规划模型来优化物流服务供应链网络.对物流服务的参与实体以及服务属性,如服务质量、服务能力、服务成本、交付时间等进行了定义并给出了计算公式.目标函数和约束条件的设定兼顾了物流服务的串行与并行过程.用案例验证了该模型的可解性.     

一种基于特征建模的CAD系统的研制

本文介绍了一种基于特征建模的CAD系统,指出了在CAD/CAPP/CAM集成系统中,CAD系统应具有的功能。该系统以特征建模为基础,具有新颖的几何造型手段,完备的零件特征信息,功能完善的图形系统。系统既可以输出完整、规范、直接用于生产的零件图纸,又可以向CAPP系统提供所需要的全部信息,并已实现了与CAPP/CAM系统的集成。     

一种非结构环境下多机器人构建地图的方法

提出了一种多移动机器人在非结构环境下构建地图的新方法.该方法让各机器人独立探索环境并对不同的局部栅格地图予以融合.在地图融合过程中,无需考虑机器人相对位置的先验信息,而是以栅格地图相似度为度量标准,利用距离变换和改进的遗传算法高效、快速地搜索各局部地图之间的最大重叠部分,进而予以融合.实验结果表明,与常规方法相比,该方法能够较为精确地实现非结构环境下多机器人地图构建,且限制条件少,更适合于实际应用中的各种复杂情况.     

基于可视切线图的未知环境建模新方法研究

针对移动机器人路径规划的环境建模问题,提出了一种基于可视切线图的未知环境建模新方法。首先给出可视切线图的定义,其节点为障碍物边界上的可视切点,边为视点与可视切点间的切线段。其次为避免机器人与障碍物相碰,对可视切线图进行了扩展。最后在建立可视切线图的基础上,采用两种启发函数搜索全局目标指导下的局部最优路径。仿真分析证明,可视切线图的数据结构简单,所需存储空间小,具有较好的环境适应能力,是一种有效的路径规划工具。     

一种面向CAPP的机械结构零件信息建模方法

提出了一种基于Windows环境的机械结构零件信息建模方法——分层分类嵌套式建模(HCEM)法,详细阐述了HCEM的设计思想、具体结构及其数据表达形式,结合工厂的具体实例做了进一步的说明。     

一种面向CAPP的机械结构零件信息建模方法

提出了一种基于Ｗｉｎｄｏｗｓ环境的机械结构零件信息建模方法一分层分类嵌套式建模法，详细阐述了ＨＣＥＭ的设计思想，具体结构及其数据表达形式，结合工厂的具体实例做了进一步的说明。     

一种用于飞机识别的三维建模方法

提出了基于垂距逐步递推的自由曲面自适应数据采样的新算法,给出了应用该算法对复杂曲面物体外形重构和建模方法。自由曲面自适应数据采样时,首先运用逆向工程测量方法,获得曲面的截面数据点列,用非均匀三次B样条曲线拟合出截面轮廓曲线;然后利用基于垂距的数据采样算法,对拟合曲线上的数据点进行重新采样,达到优化数据点的分布及减少描述曲线数据量的目的。最后运用蒙面法完成物体外形轮廓曲面重构和建模。仿真结果表明算法简便、有效。     

参数化特征造型工具系统FMT

介绍了参数化特征造型工具系统ＦＭＴ，该系统具有特征造型、参数化设计、公差分析与综合、有限元建模等功能，初步实现了ＣＩＭＳ环境下的ＣＡＤ／ＣＡＭ集成。     

基于递归神经网络的传感器非线性动态建模

根据动态校准实验结果建立传感器的动态数学模型,以研究传感器的动态性能,是动态测试的一个重要内容。讨论了递归神经网络模型在传感器动态建模中的应用,给出了递归神经网络模型的结构及相应的训练算法。由于其反馈特征,使得递归神经网络模型能获取系统的动态响应。该方法特别适用于传感器非线性动态建模,而且避免了传感器模型阶次的选择的困难。试验结果表明,应用递归神经网络对传感器进行动态建模是一种行之有效的方法。     

基于MAS的船舶修理企业生产管理模型研究

针对当前船舶修理过程的特点和存在的问题,结合目前船舶修理企业的现状,提出了基于Multi Agent System(MAS)的船舶修理企业生产管理模型,建立了管理Agent (MA)、报价Agent(QA)、修理单Agent(OA)、生产Agent(PA)、检测Agent(IA)和安全Agent(SA),并论述了各Agent的功能.同时,基于MAS构建PA,PA包括资源Agent(RA),外包工人Agent(WA)和任务Agent(TA).各Agent之间信息共享和传递,实现数据流和业务流的集成.     

A Method for Modelling the Nonlinear Viscoelastic Response of Polymers

An explicit mechanical model with multiple units which each comprise an activated viscous element and an elastic element is applied to model the nonlinear response of polymers below and up to the glass transition temperature. Considerations of molecular mechanisms in the context of the energy landscape lead to extensions to the properties of the elements, which produce a stress related slowing and a yield peak, a stress dependent reduction in tangent modulus, and a stress related increase in the recovery rate. The response of the model to strain and stress input deformations is visualised by approximate analytical techniques, which show it to be more appropriate than a stress-time shift. They further provide the basis for the construction of models which quantitatively reproduce the response of polymers, under a range of stresses, deformation histories and temperatures. Successful comparisons of model response and experimental data are made for 22 sets of data on six materials, drawn from the reports of 13 investigations available in the literature.     

Modelling control of epidemics spreading by long-range interactions

We have studied the spread of epidemics characterized by a mixture of local and non-local interactions. The infection spreads on a two-dimensional lattice with the fixed nearest neighbour connections. In addition, long-range dynamical links are formed by moving agents (vectors). Vectors perform random walks, with step length distributed according to a thick-tail distribution. Two distributions are considered in this paper, an α-stable distribution describing self-similar vector movement, yet characterized by an infinite variance and an exponential power characterized by a large but finite variance. Such long-range interactions are hard to track and make control of epidemics very difficult. We also allowed for cryptic infection, whereby an infected individual on the lattice can be infectious prior to showing any symptoms of infection or disease. To account for such cryptic spread, we considered a control strategy in which not only detected, i.e. symptomatic, individuals but also all individuals within a certain control neighbourhood are treated upon the detection of disease. We show that it is possible to eradicate the disease by using such purely local control measures, even in the presence of long-range jumps. In particular, we show that the success of local control and the choice of the optimal strategy depend in a non-trivial way on the dispersal patterns of the vectors. By characterizing these patterns using the stability index of the α-stable distribution to change the power-law behaviour or the exponent characterizing the decay of an exponential power distribution, we show that infection can be successfully contained using relatively small control neighbourhoods for two limiting cases for long-distance dispersal and for vectors that are much more limited in their dispersal range.     

基于Internet／Intranet的质量信息系统重构技术研究

研究了基于ｗｅｂ浏览器的质量信息系统运行方式和质量信息系统的重构分类方法，在此基础上，提出了基于Ｉｎｔｅｒｎｅｔ／Ｉｎｔｒａｎｅｔ质量信息系统的结构框架和重构流程，以此来映射和完成基于Ｉｎｔｅｒｎｅｔ／Ｉｎｔｒａｎｅｔ的质量信息系统的功能，以适应敏捷制造中动态联盟的结构变化性和快速响应的要求。     

Split Hopkinson pressure bar testing of 3D woven composites

Results from a series of split Hopkinson pressure bar (SHPB) tests on 3D woven tetxile composites (3DWC) are presented. These tests were done to determine the rate dependent compression response of 3DWC. Three different configurations of the 3DWC, corresponding to compression response in the plane of the material and through-the-thickness direction (out-of-plane) were studied. The rate dependent responses were compared against quasi-static test results and it was found that 3DWC showed an increase in strength in all three directions studied, however, accompanied by a transition in the failure mechanism. The in-plane orientations showed the largest increase in (about 100%) strength at the elevated rates of loading. A follow-on paper provides finite element based results that correspond to the experimental results presented here.     

A generic tool for cost estimating in aircraft design

A methodology to estimate the cost implications of design decisions by integrating cost as a design parameter at an early design stage is presented. The model is developed on a hierarchical basis, the manufacturing cost of aircraft fuselage panels being analysed in this paper. The manufacturing cost modelling is original and relies on a genetic-causal method where the drivers of each element of cost are identified relative to the process capability. The cost model is then extended to life cycle costing by computing the Direct Operating Cost as a function of acquisition cost and fuel burn, and coupled with a semi-empirical numerical analysis using Engineering Sciences Data Unit reference data to model the structural integrity of the fuselage shell with regard to material failure and various modes of buckling. The main finding of the paper is that the traditional minimum weight condition is a dated and sub-optimal approach to airframe structural design.     

Modelling of Elastic and Strength Properties of Structural Plastics Based on Composites of Polymers with Fiber and Other Fillers

Modelling is considered for the elastic and strength properties of filled polymer composites taking account of the increase in the elasticity modulus of polymer absorbed at the surface of the filler as a result of polarization.__________Translated from Izmeritel’naya Tekhnika, No. 6, pp. 63–66, June, 2005.     

Modelling of plate finned tube evaporators and condensers working with R134A

A model to predict the behaviour of finned tube evaporators and condensers working with R134a has been developed. For modelling of the refrigerant phase change, evaporation or condensation, the heat transfer and the pressure drop for the two-phase flow have to be calculated. Therefore, a number of correlations, the most recommended ones in the reviewed literature, have been analysed and compared. The results of this comparison are presented for the evaporation and condensation heat transfer coefficients and for the evaporator frictional pressure drop. Once the correlations have been implemented in the model and compared with the experimental results, the ones that work best for the studied heat exchangers have been ultimately selected.The experimental study to validate the model has been carried out in a small airconditioning unit with cross-flow air-refrigerant type heat exchangers. The results are compared with model predictions for thermal capacity, refrigerant superheat or subcooling, and tube-side pressure drop.