An intelligent integrated optimization system for the proportioning of iron ore in a sintering process

The proportioning of iron ore is the first step of the sintering process. It mixes different kinds of iron ores with coke, limestone, dolomite, and returned sinter to produce a raw mix for the production of qualified sinter. The chemical components and proportions of the raw materials determine the chemical and physical characteristics of the resulting sinter, and thus the quality of the sinter and the amount of SO₂ emissions. The prices of the raw materials and their proportions determine the price of the sinter. In this study, an intelligent integrated optimization system (IIOS) was developed for the proportioning step, which contains two phases: the first and second proportionings. First, the sintering process was analyzed, and the requirements of the proportioning step were specified. Next, an IIOS with two levels (intelligent integrated optimization, basic automation) was built. In the intelligent integrated optimization level, an intelligent integrated optimizer (IIO) produces an optimal dosing scheme. The IIO has three parts: a cascade integrated quality-prediction model, the optimization of the first proportioning, and the optimization of the second proportioning. Computational intelligence methods predict the quality of sinter. Then, the predicted quality indices are fed back to the optimizations of the first and second proportionings to find feasible optimal dosing schemes. The IIOS was implemented in an iron and steel plant. Actual runs show that the system reduced production costs by 43.014 CNY/t and SO₂ emissions by 0.001% on average.     

基于工况识别的辊式淬火过程板形预报方法

板形是衡量淬火后钢板质量的重要指标之一,板形的预报对高质量钢板的持续稳定生产具有重要的指导意义.本文提出一种基于工况识别的辊式淬火过程板形预报方法,为淬火生产控制决策提供参考依据.首先对淬火过程进行特性分析;然后采用模糊C均值聚类算法对淬火过程进行工况识别,使用支持向量机建立各工况的板形预报模型,并运用改进的粒子群优化...     

A hybrid just-in-time soft sensor for carbon efficiency of iron ore sintering process based on feature extraction of cross-sectional frames at discharge end

Iron ore sintering is the second-most energy-consuming process in steelmaking. The main source of energy for it is the combustion of carbon. In order to reduce energy consumptions and improve industrial competitiveness, it is important to improve carbon efficiency. Reliable online prediction of the carbon efficiency would be extremely beneficial for making timely adjustments to the process to improve it. In this study, the comprehensive carbon ratio (CCR) was taken to be a measure of the carbon efficiency; and a soft sensing system was built to make an online estimation of the CCR. First, the sintering process was analyzed, and the key characteristics of the process parameters were extracted. Then, the configuration of the soft sensing system was devised based on the characteristics of the process. The system consists of three parts: an image selection, an image segmentation, and a hybrid just-in-time learning soft sensor (HJITL-SS). First, an image selection method was devised to automatically select the key frames (KFs) from the video taken at the discharge end of the sintering machine. Then, a genetic-algorithm-based fuzzy c-means clustering method was devised to extract feature parameters from the KFs. Finally, an HJITL-SS, which consists of online and offline submodels, was devised to estimate the CCR using the extracted feature parameters as inputs. Actual run data were used to verify the validity of our system. Accuracy, overfitness, and error distribution of the HJITL-SS, offline, and JITL-based soft sensing methods were compared, which show the validity of the HJITL-SS. The actual run results also show the validity of the soft sensing system with 97% of the actual runs are in an acceptable range.     

Modeling and optimization method featuring multiple operating modes for improving carbon efficiency of iron ore sintering process

Iron ore sintering is one of the most energy-consuming processes in steelmaking. Since its main source of energy is the combustion of carbon, it is important to improve the carbon efficiency to save energy and to reduce undesired emissions. A modeling and optimization method based on the characteristics of the sintering process has been developed to do that. It features multiple operating modes and employs the comprehensive carbon ratio (CCR) as a measure of carbon efficiency. The method has two parts. The first part is the modeling of multiple operating modes of the sintering process. K-means clustering is used to identify the operating modes; and for each mode, a predictive model is built that contains two submodels, one for predicting the state parameters and one for predicting the CCR. The submodels are built using back-propagation neural networks (BPNNs). An analysis of material and energy flow, and correlation analyses of process data and the CCR, are used to determine the most appropriate inputs for the submodels. The second part of the method is optimization based on a determination of the optimal operating mode. The problem of how to reduce the CCR is formulated as a two-step optimization problem, and particle swarm optimization is used to solve it. Finally, verification of the modeling and optimization method based on actual process data shows that it improves the carbon efficiency of iron ore sintering.     

基于GMM的多模态过程模态识别与过程监测

多模态复杂过程的多变量、多工序、变量时变性以及模态转换时间不确定等多种原因, 导致面向多模态生产过程的监测问题十分复杂. 对此, 基于高斯混合模型的监测方法, 结合定性知识和定量知识, 解决了多模态过程监测中离线数据模态划分、稳定模态和过渡模态的监测模型建立以及在线数据的模态识别等关键问题, 最终实现了对多模态过程的监测.     

Hybrid multistep modeling for calculation of carbon efficiency of iron ore sintering process based on yield prediction

Iron ore sintering is the second most energy-consuming process in steelmaking. The main source of energy for it is the combustion of carbon. To find ways of reducing the energy consumption, it is necessary to predict the carbon efficiency. In this study, the comprehensive carbon ratio (CCR) was taken to be a measure of carbon efficiency, and a hybrid multistep model (HMSM) was built to calculate it. First, the sintering process was analyzed, and the key characteristics of the process parameters were extracted. Next, an HMSM that combines mechanism modeling, data-driven modeling, and integrated modeling was constructed based on the characteristics of the process parameters. The model has three levels: the prediction of key state parameters, yield prediction, and mechanism modeling. First, an integrated fuzzy predictive model predicts the key state parameters based on the evaluation of current operating conditions. Next, predicted values of the state parameters along with key material parameters are used as inputs for a particle swarm optimization-based backpropagation neural network predictive model that predicts the yield. Finally, the predicted yield is fed into the mechanism model, which calculates the CCR. Mechanism and data correlation analyses were used to determine the most appropriate inputs for the three levels. Model verification using actual process data showed that the HMSM accurately predicted the CCR. More specifically, the relative error was in the range (0 %, 2 %] for 91 % of the test samples, and the maximum error was only 5 %. This model lays the groundwork for increasing the carbon efficiency of iron ore sintering.

     

An intelligent modeling and analysis method of manufacturing process using the first-order predicate logic

Manufacturing process refers to machining sequence from raw materials to final products. Process plan has important effects on manufacturing process. In general, process designer relies on his experience and knowledge to arrange the process plan. For a complex part, it takes long time and effort to determine process plan. In this paper, an intelligent modeling and analysis method using the first-order predicate logic is proposed to evaluate the manufacturing performance. First, the logic predicates used to represent the process plan are defined according to the machining methods, and the predicate variables are discussed in detail. Consequently, the process plan can be represented in the form of the first-order predicate logic. Second, a type of element model composed of four nodes and four links is put forward in order to construct the process model. All components in this element model are respectively explained, and the mapping relationship between element model and predicate logic is described in detail. According to engineering practices, logic inference rules are suggested and the inference process is illustrated. Hence, the manufacturing process model can be constructed. Third, the process simulation is carried out to evaluate the performance of manufacturing system by using measures such as efficiency, the machine utilization, etc. Finally, a case study is given to explain this intelligent modeling method using the first-order predicate logic.     

基于“大数据”理念的智能化服务管理新模式

为加快北京地区国际一流配电网建设进程,实现电力企业营配业务末端融合,提升公司精益化管理水平,本文基于“大数据”理念,分别从电网规划、安全生产、基础管理和优质服务四个领域建立信息化管理模式;以“大数据”平台为基础数据支撑和决策支撑,以供电服务指挥中心“接派发工单业务”和“故障抢修处置指挥业务”两项业务为切入点,应用“大数据”理念实现配网报修工单的可视化实时监视、频繁停电时间的统计和综合分析以及配抢业务可视化指挥沙盘等功能,创新构建智能化服务管理新模式。实践证明基于“大数据”理念的智能化服务管理新模式为国网北京城区供电公司的政治供电保障、营配业务贯通提供了强有力的数据信息支撑,具有良好的推广及应用前景。     

基于集成模型与遍历搜索算法的铅锌烧结透气性优化

以铅锌烧结过程为研究对象,针对烧结过程透气性的控制问题,提出了基于集成预测模型与遍历优化搜索算法的铅锌烧结透气性优化控制方法.首先采用优化组合集成技术将神经网络预测模型和灰色系统预测模型有机结合,建立烧结综合透气性集成预测模型,然后结合14# 风箱温度和烧穿点温度建立透气性状况综合评判模型,最后通过遍历优化搜索算法,获得二配配比和混合料水分设定值,并进行跟踪控制,从而实现烧结过程透气性的优化控制.仿真结果表明:该方法能有效改善烧结过程的透气性.稳定烧结过程.     

基于系统动力学的自然灾害应急物流逆向回收决策研究

为了辅助突发性自然灾害下应急物流的逆向回收决策, 在总救援满意度优先的原则下, 从系统动力学角度出发对多受灾点下可重复利用物资的逆向回收过程进行系统建模, 综合分析了受灾点对物资的需求及逆向回收占用资源等其他因素, 建立了回收频率与救援满意度之间的函数关系, 并利用系统动力学软件Vensim对系统模型进行仿真。最后, 通过算例证明了该模型的有效性和实用性, 在此基础上分析了运输资源变化对救援满意度的影响。基于上述研究结论, 为我国应急逆向物流提供了决策支持和对策建议。     

基于简化 Takagi- Sugeno 模糊模型的系统镇定策略

针对Takagi—Sugeno型模糊控制器设计方法计算复杂且难以求解的问意，在分析原因的基础上，利用模糊规划将系统的输入输出空间划分为一个完备的模糊模式集，通过寻找与实时输入对应的模糊模式，对整个系统进行了筒化。将该模型筒化算法应用于一类非线性系统镇定问题的求解，利用Lyapunov穗定性分析理论和线性矩阵不等武等工具推导了闭环系统的可镇定条件，进而设计了相应的简化Takagi—Sugeno型模糊状态反馈控制器。仿真结果表明了这种模型简化方法的有效性。     

Operation optimization of hydrocracking process based on Kriging surrogate model

Hydrocracking is one of the key technologies in oil refining. It has become a critical secondary processing unit in the refinery for improving the quality of product oil and increasing the light oil volume of production. As such, operation optimization for this process is significant. The basis of operation optimization is the model, and several mechanisms for hydrocracking models have been proposed and studied. However, these models usually require time consuming and exhibit low efficiency especially when applied to optimize operating conditions. In this study, a Kriging surrogate model of hydrocracking is developed based on the mechanism and industrial data. An optimization algorithm is then proposed to optimize operating conditions. The proposed algorithm integrates adaptive step-size global and local search strategy (GLSS) for minimizing the predictor. Simulation results indicate that this optimization strategy integrating GLSS and Kriging surrogate model obtains better revenue of the process production than conventional algorithms such as EGO, DDS, and CAND.     

基于PNN和IGS的铅锌烧结块成分智能集成预测模型

针对复杂的烧结块成分预测问题, 提出一种基于过程神经网络和改进灰色系统的铅锌烧结块成分智能集成预测模型. 首先利用过程神经网络可充分表达时间序列中时间累积效应、灰色系统可弱化数据序列波动性的特点, 分别对烧结块成分进行预测, 然后从信息论的观点出发, 提出一种确定各预测模型加权系数的熵值递推算法, 通过对两个预测模型的预测结果进行加权集成, 获得更加准确的铅锌烧结块成分预测结果. 结果表明, 智能集成模型 的预测精度高于单一预测模型, 能有效地对烧结块成分进行预测, 满足了配料计算对预测精度和数据完备性的     

基于层次分析法的模糊分类优选模型

不同的模糊分类算法在同一个数据集合上常会产生不同的模糊分类．究竟哪种方法最能揭示数据的真实结构，对此，以模糊分类有效性指标为评价指标，应用层次分析法对各模糊分类进行综合评价，建立了一个模糊分类优选模型．大量实验表明，该优选模型所选出的最优模糊分类，其模式识别率高，能揭示数据的真实结构．     

基于证据距离的改进DS/AHP 多属性群决策方法

证据推理/层次分析(DS/AHP)方法采用了AHP法的层次结构模型和证据理论的分析过程,为不确定多属性决策问题的解决提供了新思路,但其在构造知识矩阵中用0代表残缺信息是不合理的.鉴于此,对DS/AHP方法进行了改进,并将改进后的方法拓展到群决策中,研究了专家群体权向量的确定方法.具体地,引入证据距离的概念,通过计算专家证据的综合距离来对专家赋权,体现了群决策中的多数人规则.     

化工过程故障原因诊断的变量异常顺序法

为对化工过程故障进行实时诊断,建立设了备的主元分析(Principal component analysis,PCA)模型,根据实时数据和PCA模型计算综合指标以在线检测其故障的发生,并提出了PCA模型的在线更新策略,以适应实际过程中工况缓变特性。为在线监测到故障发生时,能确定故障根原因,根据各变量的DCS报警上下限判断其异常状态,并记录各变量出现异常的时间顺序,以供操作人员参考,从而准确地诊断所发生故障的根源。基于过程安全生产指导平台,将所提出的方法实际应用于某炼油厂延迟焦化装置的分馏塔单元,长期在线应用结果表明所提出的在线更新PCA模型能准确地连续检测出故障的发生并适应工况的缓变,而变量异常顺序可帮助操作人员正确地确定故障原因。     

Fuzzy multiple attributes group decision-making based on the ranking values and the arithmetic operations of interval type-2 fuzzy sets

In this paper, we present a new method to handle fuzzy multiple attributes group decision-making problems based on the ranking values and the arithmetic operations of interval type-2 fuzzy sets. First, we present the arithmetic operations between interval type-2 fuzzy sets. Then, we present a fuzzy ranking method to calculate the ranking values of interval type-2 fuzzy sets. We also make a comparison of the ranking values of the proposed method with the existing methods. Based on the proposed fuzzy ranking method and the proposed arithmetic operations between interval type-2 fuzzy sets, we present a new method to handle fuzzy multiple attributes group decision-making problems. The proposed method provides us with a useful way to handle fuzzy multiple attributes group decision-making problems in a more flexible and more intelligent manner due to the fact that it uses interval type-2 fuzzy sets rather than traditional type-1 fuzzy sets to represent the evaluating values and the weights of attributes.     

基于多特征的PSO-MSVM动态过程质量异常模式识别

为了提高动态过程质量异常模式识别效率,将动态过程质量模式的均值特征与小波包分解特征作为分类特征,并构建两层多支持向量机识别模型进行分类.利用均值特征,在第一层MSVM中把动态过程变化趋势划分为正常与周期、上升与向上阶跃、下降与向下阶跃三大类别;采用小波包分解特征,在第二层MSVM中对这三大类别进行再分类.仿真结果表明提出的识别模型的识别精度相比采用单一特征的识别模型有明显提高.     

基于IGS和SVM的烧结返矿量智能集成预测模型

针对烧结返矿量难以进行有效预测的问题,提出一种智能集成预测模型.首先利用改进灰色系统和支持向量机两个单一模型分别对返矿量进行预测;然后基于预测精度的数学期望和标准差,通过求取最优加权系数,建立烧结返矿量智能集成预测模型进行返矿量集成预测.运行结果表明,该集成模型的预测精度高于单一模型,能有效地对返矿量进行预测.