比较两个线性模型的拟合优度的对比检验方法

为了比较两个线性模型的拟合优度哪一个高,本文提出了对两个模型的拟合优度进行假设检验的方法,对该方法的原理进行了论证。该方法克服了其他方法的局限性,具有较广的适用性,能对两个模型的拟合优度作出定量的比较。     

基于统计规律的爆破优化实用模型

以矿山生产一个经济独立核算单位作为研究系统，分析了矿山爆破优化实用模型的一般形式和优化方法；以两个矿山实例分别介绍了以现场统计资料建模和用煤破破碎度方程建模，以及这两种基于统计分析建模方法的具体作法。     

均热炉优化加热制度的计算和分析

本文根据控理论线性模型推出的均热炉优化加热方法,利用非线性模型对两段保温式的优化加热工艺进行了计算和分析,证明这是一种节能型的加热方法.这一优化节能工艺首次用于莱钢均热炉控制系统,显示了明显的节能效果.     

热连轧机板形板厚解耦控制的逆系统方法研究

提出一种解决热连轧机板形板厚解耦控制的逆系统方法；考虑热连轧机板形板厚的耦合性，在控制系统中加进一个“逆系统”，解耦线性化后，按照系统要求进行控制系统设计；在建立了热连轧机的非线性全量模型和线性增量模型基础上，分别构造了板形板厚解耦控制的非线性逆和线性逆解耦控制器，并用C语言编写了6机架仿真程序。通过仿真结果可以看出非线性逆的控制性能明显优于线性逆控制器。     

基于并行计算的过程控制系统的研究与实现

基于并行计算机体系结构和并行计算的思想，结合中厚钢板的生产过程和工艺特点，作者从系统结构和软件实现两方面着手设计了一个由多个子系统构成、子系统间通信速率高、整个系统实时性强的过程控制系统模型，在鞍钢的应用实践证明，该系统完全符合过程控制要求。     

热轧板卷Q235B性能预报模型对比与分析

马钢第四钢轧总厂生产的热轧板卷Q235B的力学性能采取线性回归模型进行性能预报,利用建立线性回归模型的数据建立神经网络预报模型,对两种模型进行对比与分析。     

连铸最佳拉速一频率线性控制模型

本文提出了最佳拉速一频率线性控制模型的概念，在振动参数工业试验的基础上给出了该模型的建立方法。     

攀钢1220mm冷连轧机数学模型的长期自适应分析

攀钢１２２０ｍｍ冷连轧机主轧机组控制系统为两级计算机系统：一级控制计算机完成基础自动化控制，实现轧线设备的控制与实测数据的采集等功能；二级控制计算机完成过程控制，进行模型计算、轧制数据管理等功能。冷连轧机的轧制规程设定计算模型一般分为两种：一种是以轧制理论为主的理论模型；另一种是以实际轧制数据为主的经验模型。在实际使用时，这两种模型相互联系，只是侧重面不同。攀钢１２２０ｍｍ冷连轧机的设定模型是以经验为主的模型。它将标准轧制参数以表格形式存储，在设定计算时，根据来料情况进行修正计算，以得出相应的轧…     

神经网络在奥氏体钢设计中的应用

采用人工神经网络分别对奥氏体钢的相变临界点Ｍｓ、Ｍｅｓ，力学性能和化学成分间的关系建立了非线性网络模型，并通过试验数据验证了这些模型的正确性。此方法不同于以线性回归为基础来推导得到经验公式。它具有容错性好，通用性强等优点，神经网络的应用为材料的设计与应用提供了一种较为可靠的新途径。     

镍闪速熔炼过程的模糊建模

针对冶金工业中镍闪速熔炼复杂工艺过程,提出了利用模糊理论建立镍闪模型的方法。一种方法是利用专家知识和操作经验（即ＩＦ－ＴＨＥＮ规则）建立闪速炉的先验模型;另一种方法是利用自适应模糊神经网络方法建立闪速炉的学习模型。综合考虑两种模型的建模结果,建立整个的模型。经过两个月的现场离线指导表明,这种建模方法能够较为准确地反映镍闪速炉的运行过程。     

Real-Time Substructure Tests Using Hydraulic Actuator

A new real-time substructure method for testing systems under dynamic loading is described. The method separates a complex system into a physical, possibly nonlinear, subsystem (to be tested experimentally at large scale) and a surrounding linear system, modeled numerically. The two subsystems interact in real time allowing realistic time-dependent nonlinear behavior to take place. This behavior may be impossible to model computationally, and the method overcomes problems associated with scaling and time-dependent effects associated with current shaking table and pseudodynamic test methods. Dynamic forces are applied to the numerical model, and the resulting displacements at the interface between the two subsystems are applied to the physical system using servohydraulic actuators. The restoring forces are then measured and fed back to the numerical model, so that the response for the next time step can be calculated. The technique can be applied to a wide range of complex, linear∕nonlinear systems such as structures with localized plastic deformation, soil-structure interaction, or vehicle-suspension interaction. The method is demonstrated for both single and multi-degree-of-freedom systems, using a single actuator to apply displacements to a physical specimen. Comparisons between experimental and theoretical results show excellent agreement.     

Power Series Approach to Holistic Sewer System Modeling

Fast and stable mathematical models for the computation of sewer system outflow are essential for real-time control of urban storm drainage systems. This paper presents a general method to design such models based on the reservoir approach. The unknown inflow-outflow function is developed into a power series. The a priori assumptions made for this are much weaker than the ones for the well-known linear models. The resulting models are nonlinear, but they subsume some of the linear models, depending on the selection of model parameters. Thus, a more general approach to validate the frequently made linearity postulation of the outflow process is provided. The new model is tested with some subcatchments of a larger urban storm drainage network.     

Optimization of the ironmaking-steelmaking sequence in an integrated steel plant having non-linear and distributed elements

A mathematical technique is proposed for the optimization of large scale metallurgical operations whose mathematical models contain linear, nonlinear, and possibly distributed elements. The computational procedure consists of optimization of the nonlinear or distributed subsystems using special purpose techniques. These results are then incorporated into a linear program representing the system as a whole. The overall scheme involves an iterative procedure, through which the discrepancies are reconciled between the subsystem and total system optimization. It is thought that the technique is a practical means for optimizing actual large scale metallurgical operations. To illustrate this fact an example is given dealing with the optimization of the primary end of an integrated steelplant.     

On measures of explained variance in nonrecursive structural equation models.

Whereas measures of explained variance in a regression and an equation of a recursive structural equation model can be simply summarized by a standard R2 measure, this is not possible in nonrecursive models in which there are reciprocal interdependencies among variables. This article provides a general approach to defining variance explained in latent dependent variables of nonrecursive linear structural equation models. A new method of its estimation, easily implemented in EQS or LISREL and available in EQS 6, is described and illustrated. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

全连铸生产物流管制的数学模型及应用

通过对全连铸生产物流管制的子系统数学描述和系统的整体，协调及匹配性的描述，构造了系统实现的总体框架，提出了系统的研究内容及其多种研究方法，给出了系统的计算机实现的具体方法和目标，可供实际生产参考。     

Linear equality restrictions in regression and loglinear models.

Describes a simple method for implementing general linear equality restrictions on the parameters of linear models. These techniques, unlike those involving Lagrangian multipliers, can be easily implemented on common computer programs such as SPSS, BMDP, and SAS. For multiple regression, both homogenous and nonhomogenous constraints can be made, whereas for loglinear models only homogenous constraints can be made. (16 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The importance of shared environmental influences in explaining the overlap between mother's parenting and sibling relationships: Reply to Neale (1999).

This article addresses concerns raised by M. C. Neale (see record 1999-15302-008) in his commentary on the D. A. Bussell et al. (see record 1999-15302-007) Nonshared Environment in Adolescent Development (NEAD) study. These concerns fall into two categories: (a) model assumptions and sample design and (b) testing of alternative models. The validity of the assumptions of quantitative genetic models is a concern for all researchers in this area. Discussion of those assumptions in this reply is brief and focuses on those most relevant to the NEAD sample. The two alternative models proposed by Neale were designed to provide alternatives to the large shared environmental effect found in the original report of Bussell et al. Because these alternative models did not provide a better fit, the appropriateness of Bussell et al.'s basic model and the importance of shared environmental influences for explaining the association among family subsystems are supported. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Numerical Study of Reinforced Soil Segmental Walls Using Three Different Constitutive Soil Models

A numerical finite-difference method (FLAC) model was used to investigate the influence of constitutive soil model on predicted response of two full-scale reinforced soil walls during construction and surcharge loading. One wall was reinforced with a relatively extensible polymeric geogrid and the other with a relatively stiff welded wire mesh. The backfill sand was modeled using three different constitutive soil models varying as follows with respect to increasing complexity: linear elastic-plastic Mohr-Coulomb, modified Duncan-Chang hyperbolic model, and Lade’s single hardening model. Calculated results were compared against toe footing loads, foundation pressures, facing displacements, connection loads, and reinforcement strains. In general, predictions were within measurement accuracy for the end-of-construction and surcharge load levels corresponding to working stress conditions. However, the modified Duncan-Chang model which explicitly considers plane strain boundary conditions is a good compromise between prediction accuracy and availability of parameters from conventional triaxial compression testing. The results of this investigation give confidence that numerical FLAC models using this simple soil constitutive model are adequate to predict the performance of reinforced soil walls under typical operational conditions provided that the soil reinforcement, interfaces, boundaries, construction sequence, and soil compaction are modeled correctly. Further improvement of predictions using more sophisticated soil models is not guaranteed.     

Robust Stationkeeping Control for Libration Point Quasi-Periodic Orbits

Libration orbit stationkeeping controls are designed based on selected reference quasi-periodic orbit trajectories. The baseline trajectory is designed to meet science requirements and in the same time achieve minimum fuel consumptions. The success of finding libration point reference orbits is based on accurate numerical computation, dynamics, and space environment modeling. The linear quadratic regulator controller has been developed widely for maintaining a spacecraft in such libration orbit reference trajectories as close as possible. However, any dynamics models, including the circular restricted three-body dynamics, space environment, sensor, and actuator, are only approximations of real physical systems. Any noise and uncertainties can cause spacecraft’ motion to diverge due to the high instability region around libration points. This study investigates the modeling and designing of a passive robust μ controller and an active adaptive linear quadratic regulator in libration point stationkeeping controls around L1. The adaptive law in the linear quadratic regulator is used to estimate unknown gains of spacecraft’ subsystems. The results are compared for a family of libration orbits with reasonable ΔV yearly budgets under the influence of perturbations, noise, and unmodeled dynamics. The comparison with a publicly accessible work indicates that the controller developed in this work can provide comparable annual cost by nearly even including the worst case of perturbations.