自动导引车多Agent系统研究

多AGV系统的研究是移动机器人研究的一个重要方向，随着工厂自动化的不断发展及实际需求的推动，对多AGV系统的研究日益广泛和深入。多Agent理论是本文的核心指导理论，它来源于分布式人工智能（DAI）。分布式人工智能分为分布式问题求解（DPS）和多Agent系统（MAS）两个方向。由于MAS比DPS更能体现人类社会智能，具有更大的灵活性和适应性，更适合开放、动态的世界环境，因而越来越受到人们的重视。本文对Agent理论、Agent的基本结构、Agent的应用思想、多Agent系统的协调与协作等进行了详细地介绍。在总结了大量前人研究成果的基础上，本文认为有序是社会性的重要内涵，自主和有序是一个问题的两个方面，不能偏执一端，自主性体现了系统的灵活性，有序则体现了系统的效率。因此，我们提出了集中与分布相结合的控制机制，并成功地应用于多AGV系统的运行控制。其中涉及到了任务调度、路径规划、车辆的最优数量、通信机制、与生产系统的集成等AGES研究中的基本问题。

基于Multi-Agent的生产过程建模与仿真技术研究

某些流程行业由于采用按配方进行分组加工的模式组织生产,在排产时存在多条路径调度优化的问题,应用一般的优化算法对于现场在线调度难以给出满意结果,而基于Agent的过程仿真在解决离散、非线性系统模拟方面有显著的优势,本文采用Agent的方法对生产过程建模,然后对方案组内的备选方案进行仿真,通过对比各方案的仿真结果找到最优的方案作为执行方案,为现场的优化排产提供决策支持。

基于多Agent制造过程的建模方法

分析了制造系统与制造过程之间的关系;论证了从过程的角度对制造进行建模更恰当;结合Agent和π演算的特点,给出Agent制造系统描述模型及基于π演算的单个Agent的BDI模型,并指出Agent和π演算结合的制造过程模型有利于进行优化目标在不同制造过程层次的分解,不论从方法的角度还是实现的角度,都适合复杂系统建模。Agent和π演算相结合可以有效分析并解决离散事件的建模与仿真中的问题。

Epoxidation of propylene on NaCl-modified silver catalysts with air as the oxidant

Propylene epoxidation by air was carried out on NaCl-modified silver (NaCl/Ag) catalysts, and the catalysts were characterized by X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). The effects of NaCl loadings, propylene to oxygen ratio, and the reaction time on the catalytic performance were investigated. It was found that the addition of NaCl to silver significantly increases the propylene oxide (PO) selectivity. The PO yield has a maximum when the NaCl loading is about 10 wt.%. Also 12.4% conversion of propylene and 31.6% selectivity to PO are obtained on the NaCl/Ag (10 wt.%) catalyst at 350 degreesC, space velocity 1.8 x 10(4) h(-1) and C3H6:O-2 = 1:2. XPS and XRD characterizations show that AgCl formed on the silver catalyst was favorable to propylene epoxidation. A compound with highly oxidized Ag ion was also found, which may be effective for the reaction. (C) 2002 Elsevier Science B.V. All rights reserved.

Methane aromatization in the absence of an added oxidant and the bench scale reaction test

A bench scale reaction test for methane aromatization in the absence of an added oxidant was performed and its reaction result evaluated based on the carbon balance of the system. The result was compared with those obtained from the micro-reaction test to ensure the accuracy of the internal standard analyzing method employed in this paper. The catalytic performances of modified Mo/HZSM-5 catalysts were examined. It was found that pre-treatment by steam on HZSM-5 weakened the serious deposition of coke, and pre-impregnation of n-ethyl silicate on HZSM-5 could improve the conversion of CH4, but had little effect on coke formation. A low temperature activation procedure including pre-reduction of the catalyst with methane prevents the zeolite lattice from being seriously destroyed by high valence state Mo species when the Mo loading is high. It was suggested that Mo2C species detected by XRD spectra was the active phase for CH4 aromatization.