Gaussian process assisted coevolutionary estimation of distribution algorithm for computationally expensive problems

In order to reduce the computation of complex problems, a new surrogate-assisted estimation of distribution algorithm with Gaussian process was proposed. Coevolution was used in dual populations which evolved in parallel. The search space was projected into multiple subspaces and searched by sub-populations. Also, the whole space was exploited by the other population which exchanges information with the sub-populations. In order to make the evolutionary course efficient, multivariate Gaussian model and Gaussian mixture model were used in both populations separately to estimate the distribution of individuals and reproduce new generations. For the surrogate model, Gaussian process was combined with the algorithm which predicted variance of the predictions. The results on six benchmark functions show that the new algorithm performs better than other surrogate-model based algorithms and the computation complexity is only 10% of the original estimation of distribution algorithm.     

PX氧化反应尾气冷凝系统的模拟与优化

精对苯二甲酸(PTA)是我国最重要的化工原料,本文以某大型PTA装置的对二甲苯(PX)氧化反应尾气冷凝系统为对象,基于工艺机理,建立了该系统的模型,实现了流程模拟,获得了工艺操作条件下各流股的组分信息。并在PX氧化反应热计算的基础上,利用模型,对PX氧化反应尾气冷凝系统进行了用能评估与优化,工业装置应用实施后,调整了两级副产蒸汽,有效提高了氧化反应热的利用率,改善了PX氧化反应过程的运行性能。     

化工过程运行优化研究进展

首先介绍了化工过程运行优化的历史发展,阐述了工业过程运行优化的系统结构,对常规控制层、先进控制层、实时优化层、调度层和计划层分别作了说明,重点讨论了实时优化的研究热点;接着分析了实时优化和调度计划层的三类典型优化问题,即多目标优化、混合整数非线性规划以及动态优化;最后探讨了运行优化研究与应用在大规模化工过程建模和协同优化控制等方面所面临的挑战。     

深圳:创新管理理念 破解城市发展“水”难题

深圳作为全国加快实施最严格水资源管理制度试点城市,围绕最严格水资源管理"三条红线",把生态文明建设放在突出地位,创新管理理念,突出用水总量"控"、水资源配置"优"、节水管理"全"、非常规水资源利用"新"、水生态保护"实"、河道排水设施监管"严"的理念,取得了一定成效,较好提升了城市生态品质,保障了深圳"有质量的稳定增长,可持续的全面发展"。     

深圳市东部供水水源工程供水调度自动控制系统

深圳市东部供水水源工程全长160km，由东部引水工程，网络干线工程、宝安分部工程和位于市中心的调度中心组成，供水调度自动控制供水水源工程现代化管理的基础，是深圳市政府“三防”指挥决策支持系统的水源调度子系统，任务是对城市供水水源工程提供监测控制、数据采休处理、运行控制、优化调度及信息管理，介绍了深圳市东部供水水源工程概况，以有工程供水调度自动控制系统规划设计、功能要求、系统组成、系统优化调度和扩充的前景。     

前言

<正>冶金、化工、炼油、电力、造纸、建材等大批量连续生产的过程工业(process industry,也称流程工业)是我国国民经济建设的重要支柱.工业自动化作为过程工业不可缺少的组成部分,一直是实现生产安全、平稳、优质、高效的基本条件和重要保证.近年来,随着人工智能技术的飞速发展,以机器学习、工业大数据、工业互联网、数字孪生等为代表的新兴信息技术正深刻改变传统过程工业自动化的感知、分析、决策和执行过程,并正在向工业智能化迈进.在可预见的未来,在人工智能技术的驱动下,工业自动化的信息系统将能够认知和理解过程工业的物理系统,并实现建模、监测、控制、优化、决策的知识型工作自动化;而物理系统的执行单元将逐渐与人共融,最终实现人、机、物的有机融合,也即实现工业智能.     

一种改进的混合遗传算法及在化工过程动态优化中的应用(英文)

The solutions of dynamic optimization problems are usually very difficult due to their highly nonlinear and multidimensional nature. Genetic algorithm (GA) has been proved to be a feasible method when the gradient is difficult to calculate. Its advantage is that the control profiles at all time stages are optimized simultaneously, but its convergence is very slow in the later period of evolution and it is easily trapped in the local optimum. In this study, a hybrid improved genetic algorithm (HIGA) for solving dynamic optimization problems is proposed to overcome these defects. Simplex method (SM) is used to perform the local search in the neighborhood of the optimal solution. By using SM, the ideal searching direction of global optimal solution could be found as soon as possible and the convergence speed of the algorithm is improved. The hybrid algorithm presents some improvements, such as protecting the best individual, accepting immigrations, as well as employing adaptive crossover and Gaussian mutation operators. The efficiency of the proposed algorithm is demonstrated by solving several dynamic optimization problems. At last, HIGA is applied to the optimal production of secreted protein in a fed batch reactor and the optimal feed-rate found by HIGA is effective and relatively stable.     

基于Aspen Plus的气流床煤气化炉三段平衡模型(英文)

A three stage equilibrium model is developed for coal gasification in the Texaco type coal gasifiers based on Aspen Plus to calculate the composition of product gas, carbon conversion, and gasification temperature. The model is divided into three stages including pyrolysis and combustion stage, char gas reaction stage, and gas phase reaction stage. Part of the water produced in the pyrolysis and combustion stage is assumed to be involved in the second stage to react with the unburned carbon. Carbon conversion is then estimated in the second stage by steam participation ratio expressed as a function of temperature. And the gas product compositions are calculated from gas phase reactions in the third stage. The simulation results are consistent with published experimental data.     

改进鲸鱼优化算法及其在渣油加氢参数优化的应用

针对智能优化算法在处理非线性优化问题中存在的容易陷入局部最优和收敛精度差等问题,提出了一种基于结合差分进化和精英反向学习的改进鲸鱼算法（DEOBWOA）。该算法引入对立搜索初始化、精英反向学习,并结合差分进化进行变异修正,显著有效地提高WOA算法的收敛精度和收敛速度,提高其跳出局部最优的能力。之后采用8个标准测试函数进行仿真实验,结果表明：DEOBWOA算法与标准WOA、HCLPSO、DE算法相比,全局搜索能力和收敛速度都有较大提升。最后建立了渣油加氢动力学模型,考虑到渣油加氢过程中存在诸多典型的非线性约束问题,以某炼化厂渣油加氢装置为例,应用DEOBWOA对渣油加氢反应动力学模型参数进行优化,结果表明该算法能较好地处理实际工程优化问题。     

企业环境监测站在突发性环境污染事件中的应急监测

简述了在应对突发性环境污染事件中,与其他环境监测站相比,企业环境监测站在熟悉本企业危险源和主要污染物的情况、能迅速启动应急监测程序、可以为事故的处置和决策提供强有力的技术支持等方面具有无可替代的优势。