高分子材料配方均匀设计系统

结合实验均匀设计和逐步回归优化方法，设计了更为科学的高分子材料配方设计系统，可更准确地预测产品的性能，简化实验程序，提高实验效率。该系统特别适用于多因素多水平多指标实验，在配方变量的变化范围内，利用回归方程建立单一组分与性能间的关系，并可用于预测某一配方的性能指数，利用计算机程序在设定优化条件后可得到相应的优化配方及其性能指标。     

虚拟目标法在多指标橡胶配方试验中的应用

介绍在多响应问题中用于多目标同步优化的一种方法即虚拟目标法,并以SBR多指标配方试验为例,依据通过均匀设计法和回归分析法建立的回归方程,应用虚拟目标和网络法预测和优选出各项性能达到标的值的配方和综合性能最优的配方。     

基于多目标教学优化算法在二甲苯吸附分离过程优化中的应用

以C8芳烃混合物的吸附分离过程作为研究对象, 应用多目标教学优化算法(multi-objective teaching-learning-based optimization algorithm, MOTLBO)对模拟移动床多目标优化问题进行求解。采用TMB方法, 建立了模拟移动床模型, 并对两个典型的模拟移动床多目标操作优化问题进行了优化设计。通过与NSGA-Ⅱ算法的比较, 证明了多目标教学优化算法在求解模拟移动床多目标优化问题上的有效性和优势。此外, 还分析了抽出液流量、抽余液流量以及步进时间等对多目标优化非劣解的影响, 优化结果为模拟移动床分离过程的工艺设计和操作提供了依据。     

废轮胎热解动力学多胶体优化模型

在废轮胎热解动力学多步模型和多胶体模型基础上建立废轮胎热解动力学多胶体优化模型,并以废轮胎胶粒热解试验数据作为热解动力学模型的计算样本数据进行模拟计算.结果表明,轮胎配方多胶体优化模型计算相对误差在30%以下,与多胶体模型相比明显减小,证明多胶体优化模型是有效的.     

基于Kriging和NSGA-Ⅱ的辅以困气改善的熔接痕优化策略

从熔接痕的成型机理出发,考虑了困气状况和熔合温度对熔接痕熔合质量的影响,提出一种以困气改善辅助提升熔接痕熔合质量的方法,建立了以“气穴面积”和“熔接痕处流动前沿温度”为熔接痕熔合质量指标的多目标评价体系,并构建了一种基于Kriging模型和非支配排序遗传算法（NSGA-Ⅱ）的多目标寻优策略,以实现工艺参数的择优选择。以多孔板熔接痕优化为例,选用拉丁超立方抽样（LHS）设计实验,建立并检验反映工艺参数和优化目标之间影响规律的Kriging模型,采用NSGA-Ⅱ确定多目标优化问题的Pareto前沿及其最优解。仿真及生产实验结果表明所建立的多目标优化策略能有效实现熔接痕的多目标优化,同时以困气改善辅助提升熔接痕熔合质量的方法效果显著。     

配方的多目标优化及其在陶瓷材料中的应用

本文针对新材料开发中存在的寻求最优配方的问题,利用系统工程的观点和最优化方法,建立了成本最优和性能最优的多目标优化模型,并设计了网络算法的专用程序,可以方便地解决配方的非线性规划问题。将这一多目标优化模型应用到陶瓷材料中,取得了很好的效果。     

柴油调合工艺与短期调度集成优化方法研究

针对柴油调合短期调度过程中存在的柴油油品属性波动较大,难以预测和一次调合成功率要求高等实际应用难题,设计了1种适合实际工程应用的柴油调合工艺与短期调度计划集成优化方法,结合国内某炼油厂的柴油调合短期调度现状,建立柴油调合配方优化模型和柴油短期调度优化模型,选择线性规划算法并构建数据库及创建关联数据表,并将模型集成至基于...     

催化剂配方的神经网络建模与遗传算法优化

采用神经网络对催化剂配方实验数据建模,在网络模型仿真实验的基础上应用遗传算法对配方组成进行优化,得到的优化配方经实验验证,证实了该算法的实际应用意义.该算法对化工产品的配方及工艺优化也有实用意义.     

煤制气蒸汽动力系统多周期模拟与优化

蒸汽动力系统是煤化工的重要组成部分,为工艺提供蒸汽和动力.针对煤制气动力系统存在的能源浪费和经济亏损的问题,建立了锅炉、汽轮机、减温减压器和除氧器等关键设备的数学模型,以此集成得到蒸汽动力系统的数学模型.以系统运行成本为目标函数,采用某煤制气企业多周期的实际数据建立了混合整数非线性规划(MINLP)优化模型.优化后的系...     

基于人工神经网络的BaTiO3陶瓷配方研究

人工神经网络具有巨量并行、结构可变、变度非线性等特点，其建立数学模型并不需要预先知道太多有关问题背景的知识，这尤其适用于陶瓷配方研究中某些机理尚未完全清楚、传统数学方法无法分析的情况，本工作将人工神经网络技术用于介电陶瓷的配方性能分析，以BaTiO3为研究对象选取了几种掺杂剂，在均匀实验设计的基础上，用BP人工神经网络对所得实验结果进行了分析，并且用图形化方式直观地表达了出来，根据实验结果，并与多重非线性回归模型相比发现，人工神经网络模型比多重非线性回归模型更加准确且能给出配方组成与性能更丰富的信息，这对于研究各组分作用规律并获得介电陶瓷多性能指标的优化配方具有重要的指导作用。     

基于遗传算法求解以最大利润为目标的间歇生产过程调度问题

The optimal scheduling of multi-product batch process is studied and a new mathematics model targeting the maximum profit is proposed, which can be solved by the modified genetic algorithm (MGA) with mixed coding (sequence coding and decimal coding) developed by us. In which, the partially matched cross over (PMX) and reverse mutation are used for the sequence coding, whereas the arithmetic crossover and heteropic mutation are used for the decimal coding. In axidition, the relationship between production scale and production cost is analyzed and the maximum profit is always a trade-off of the production scale and production cost. Two examples are solved to demonstrate the effectiveness of the method.     

抗生素发酵过程优化调度模型的研究

对抗生素多罐并行发酵过程进行了分析,将任务、设备和事件之间的分配关系表达为两类0-1变量,建立了一个基于连续时间的抗生素多罐并行发酵过程优化调度的M ILP(混合整数线性规划)模型。该模型整数变量少,求解速度快,并给出了最短生产时间和罐批最优生产序列。最后以头孢菌素发酵过程为例证明了此调度模型的可行性和有效性。     

An MILP Model for Optimal Scheduling of the Lubricant Production Plant

In this article we are developing a model that can be used for determining the optimal production schedule in a lubricant production plant. The model includes all the main stages in the lubricant production process, contains both continuous and binary variables, and results in the formulation of a mixed integer linear programming (MILP) problem that is solved using standard optimization techniques. The model can be easily adapted to any lube production facility, thus providing a valuable tool to refineries in their effort to automate the production scheduling process. The proposed tool can save valuable time and resources by eliminating the time-consuming search for a feasible production plan that production engineers go through in order to meet production demands.     

Optimal operation of multicomponent batch distillation—multiperiod formulation and solution

A method is proposed to determine optimal multiperiod operation policies for binary and general multicomponent batch distillation of a given feed mixture, with several main products and intermediate off-specification cuts. A two-level optimal control formulation is presented so as to maximize a general profit function for the multiperiod operation, subject to general constraints. The solution of this problem determines the optimal amount of each main and off cut, the optimal duration of each distillation step and the optimal reflux ratio profiles during each production period. The outer level optimization maximizes the profit function by manipulating carefully selected decision variables. These are chosen in such a manner that the need of specifying the mole fractions of all the components in the products, as required by previous methods is avoided. For values of the decision variables fixed by the outer loop, the multiperiod operation is decomposed into a sequence of independent optimal control problems, one for each production step. In the inner loop, a minimum time problem is then solved for each step to generate the optimal reflux ratio values, reflux switching times and duration of the step. The procedure permits the use of very general distillation models described by differential and algebraic equations, including rigorous thermodynamics if desired. The model equations are integrated by using an efficient Gear's type method, the inner loop optimal control problems are solved using a variational method, and all optimisations are solved using a robust and efficient successive quadratic programming code (Chen, Ph.D. Thesis, Imperial College, 1988).

Several example problems (involving binary and multicomponent mixtures) are used to demonstrate the idea and to show the effect of the cost functions used (in particular the value of the main products) on the optimal solutions.     

MODELING AND OPTIMIZATION OF LACTIC ACID SYNTHESIS BY THE ALKALINE DEGRADATION OF FRUCTOSE IN A BATCH REACTOR

The present work deals with the determination of the optimal operating conditions of lactic acid synthesis by the alkaline degradation of fructose. It is a complex transformation for which detailed knowledge is not available. It is carried out in a batch or semi-batch reactor. The “Tendency Modeling” approach, which consists of the development of an approximate stoichiometric and kinetic model, has been used. An experimental planning method has been utilized as the database for model development. The application of the experimental planning methodology allows comparison between the experimental and model response. The model is then used in an optimization procedure to compute the optimal process. The optimal control problem is converted into a nonlinear programming problem solved using the sequencial quadratic programming procedure coupled with the golden search method. The strategy developed allows simultaneously optimizing the different variables, which may be constrained. The validity of the methodology is illustrated by the determination of the optimal operating conditions of lactic acid production.     

MODELING AND OPTIMIZATION OF LACTIC ACID SYNTHESIS BY THE ALKALINE DEGRADATION OF FRUCTOSE IN A BATCH REACTOR

The present work deals with the determination of the optimal operating conditions of lactic acid synthesis by the alkaline degradation of fructose. It is a complex transformation for which detailed knowledge is not available. It is carried out in a batch or semi-batch reactor. The “Tendency Modeling” approach, which consists of the development of an approximate stoichiometric and kinetic model, has been used. An experimental planning method has been utilized as the database for model development. The application of the experimental planning methodology allows comparison between the experimental and model response. The model is then used in an optimization procedure to compute the optimal process. The optimal control problem is converted into a nonlinear programming problem solved using the sequencial quadratic programming procedure coupled with the golden search method. The strategy developed allows simultaneously optimizing the different variables, which may be constrained. The validity of the methodology is illustrated by the determination of the optimal operating conditions of lactic acid production.     

气相流化床聚乙烯颗粒粒径分布的定制

基于气相法聚乙烯流化床反应器颗粒粒径分布的预测[1],提出了颗粒粒径分布定制模型.通过模型的优化计算,可得到催化剂粒径及其分布、操作气速、反应温度、乙烯浓度和丁烯浓度等生产操作参数,由此进行生产可获得具有良好流态化特性的聚乙烯颗粒粒径分布,能为生产具有特定粒径分布的聚乙烯颗粒提供理论指导.模型由工业装置的生产数据分析了计算结果的合理性.最后,以三种粒径分布的聚乙烯颗粒为例讨论了模型的可行性.同时,运用粒子群优化算法求解模型的非线性规划问题,算法具有调整参数少、收敛速度快和全局优化等优点.     

克隆转换开关的变形和微缩痕的处理技术

转换开关是工业生产自动流水线上机械手中的运动转换装置,克隆该产品需要解决多方面的技术问题才能实现.转换开关孔的精度和几何精度要求,甚至超过了金属机械加工件.如何控制克隆转换开关的变形、微缩痕和银纹等缺陷,就成为了克隆转换开关首先要面对课题.先后采用物理、化学和光谱分析方法,确定了进口转换开关的主要成份后.又通过不断试用...     

Optimal processing pathway for the production of biodiesel from microalgal biomass: A superstructure based approach

In this study, we propose a mixed integer nonlinear programming (MINLP) model for superstructure based optimization of biodiesel production from microalgal biomass. The proposed superstructure includes a number of major processing steps for the production of biodiesel from microalgal biomass, such as the harvesting of microalgal biomass, pretreatments including drying and cell disruption of harvested biomass, lipid extraction, transesterification, and post-transesterfication purification. The proposed model is used to find the optimal processing pathway among the large number of potential pathways that exist for the production of biodiesel from microalgae. The proposed methodology is tested by implementing on a specific case with different choices of objective functions. The MINLP model is implemented and solved in GAMS using a database built in Excel. The results from the optimization are analyzed and their significances are discussed.     

基于(火用)分析的氧化铝多效蒸发过程液位优化设定方法

在拜耳法生产氧化铝多效蒸发过程中,各蒸发器液位是影响流程各个参数的重要变量,对整个蒸发过程的优化操作十分重要。但实际生产中各效蒸发器液位的设定值通常是一个较大的范围,难以优化运用。针对此问题提出了一种基于(火用)分析的多效蒸发流程液位优化设定方法。在对液位作用机理分析的基础上,基于整个流程的实际生产数据,拟合得到了每效包含液位随其他参数变化的关系模型。结合蒸发流程物料平衡关系以及(火用)分析方法,建立了综合(火用)效率评价指标的能耗优化模型。最后,采用两种不同约束处理技术和状态转移算法,计算了不同酸洗周期下的各效蒸发器最优液位,得到了优化目标随各个效液位高度变化的关系曲线。