梅钢1420冷连轧机轧制力模型的开发及应用

梅钢1420轧制力模型在Hill方程基础上,分解提炼3个关键因子,建立了显函数的轧制力模型,并进行变形抗力参数和摩擦系数参数的自适应修正以提高轧制力模型精度．经生产实践数据检验,该模型自适应系数在0．9～1．1以内,满足模型在线控制要求．     

基于"当前"统计模型的一种改进机动目标跟踪算法

介绍了目前存在的机动目标运动模型.针对"当前"统计模型中加速度极限值的预先设定对于跟踪算法造成的不利影响,通过目标机动状况与相邻采样时刻间位置估计量变化之间的函数关系实现噪声方差自适应,进而提出了一种基于"当前"统计模型的改进机动目标跟踪算法.该算法避免了加速度极限值的预先设定问题,从而提高了对机动目标状态估计的精度.最后,仿真结果表明该算法具有一定的有效性.     

基于修正交叉视觉皮质模型的图像分割方法

提出了一种基于修正交叉视觉皮质模型(MICM)的图像自适应分割新方法. 根据待分割图像的自身特性,自适应地设定参数,并以互信息量为目标函数选取最佳分割结果. 该方法解决了针对不同的图像需要人工设定交叉皮质模型(ICM)参数和需要人工选取最佳分割结果的2个问题. 实验结果表明,与通过大量实验获得模型参数的脉冲耦合神经网络(PCNN)基本模型和ICM基本模型相比,MICM与其综合评价函数值相近;与模糊聚类分割算法和最大类间方差(OTSU)算法相比,MICM算法有较明显的视觉优势,并且其综合评价函数值也分别提高了约15%和13%.     

基于“当前”统计模型的一种改进机动目标跟踪算法

介绍了目前存在的机动目标运动模型，针对“当前”统计模型中加速度极限值的预先设定对于跟踪算法造成的不利影响，通过目标机动状况与相邻采样时刻间位置估计量变化之间的函数关系实现噪声方差自适应，进而提出了一种基于“当前”统计模型的改进机动目标跟踪算法，该算法避免了加速度极限值的预先设定问题，从而提高了对机动目标状态估计的精度，最后，仿真结果表明该算法具有一定的有效性。     

中厚板精轧机轧制力预报综合模型研究

为提高中厚板精轧机轧制力的预报精度,建立了Sims公式简化式与人工神经网络相结合的轧制力预报综合模型。以3 000 mm中厚板精轧机实测数据为基础,用Sims公式简化式计算轧制力主值,利用MAT-LAB人工神经网络工具箱,建立BP神经网络模型预报轧制力的偏差值,用提前结束的方法来训练网络。模型的综合采用加法和乘法两种方式。结果表明,与单独采用Sims公式简化式相比,综合模型的预报精度提高很多,而且加法网络算法的预报效果比乘法网络算法更好。     

机动目标跟踪中一种新的自适应滤波算法

通过分析基于“当前”统计模型的机动目标自适应跟踪算法,指出该算法对目标机动加速度极限值的依赖性,而实际中预先设定加速度的最大值是不可行的。为克服这一缺点,文中给出一种新的自适应滤波算法,该方法无需提前给定加速度最大值,可以直接利用位置估计值和加速度之间的函数关系进行加速度方差自适应调整。仿真结果表明,与标准的自适应滤波相比其跟踪精度有了较大提高。     

基于改进粒子群算法的连铸传热模型参数辨识

连铸传热模型是实现连铸二冷动态控制的关键,换热系数的准确性是模型成功应用的前提。本文以连铸传热模型为基础,根据四个冷却段设定的换热系数计算得到冷却段末温度,基于不同工况下的温度数据,采用改进粒子群算法对综合换热系数反向推算,以铸坯表面实际温度和计算温度差为适应度函数,优化确定二冷各段换热系数,并验证辨识参数的可靠性。仿真结果表明,该方法辨识的参数精度及重复性较好,计算温度与实际温度偏差小于3℃,满足工程应用。     

梯形不锈钢筛条堆拉系数数学模型的优化

为提高连轧过程堆拉状态的控制精度,提出填充系数对堆拉系数的影响关系,得到改进后的堆拉系数模型。借助ANSYSLS-DYNA有限元软件,建立4道次梯形不锈钢筛条的轧制三维有限元模型并进行仿真,获得轧制过程轧件填充系数、前滑系数、堆拉系数等参数。与传统堆拉系数数学模型计算结果相比,改进后的堆拉系数数学模型更能真实反映连轧过程堆拉状态。     

基于交互多模型的改进无迹粒子滤波算法

为了提高机动目标的跟踪精度,提出了适用于非线性非高斯系统的基于预测残差的交互多模型自适应无迹粒子滤波算法.该算法将无迹粒子滤波与交互式多模型的优点相结合,通过UT变化构造粒子滤波的建议分布函数,利用预测残差在线对测量协方差和状态协方差进行自适应调节,以改进执行和计算的有效性从而降低计算误差.仿真结果表明,与交互式多模型粒子滤波、交互式式无迹粒子滤波算法相比,该算法具有更好的跟踪精度.     

五机架冷连轧带钢的计算机模拟

本文论述了五机架冷连轧带钢计算机模拟的意义、基本原理和方法,列出了轧制压力、轧制力矩和前滑的数学模型,列出了基本方程组,给出了在68000微型机上运行的模拟程序和计算结果,最后,对影响系数作了较详尽的讨论。     

Preset model of bending force for 6-high reversing cold rolling mill based on genetic algorithm

The hydraulic roll-bending device was studied, which was widely used in modern cold rolling mills to regulate the strip flatness. The loaded roll gap crown mathematic model and the strip crown mathematic model of the reversing cold rolling process were established, and the deformation model of roll stack system of the 6-high 1 250 mm high crown (HC) reversing cold rolling mill was built by slit beam method. The simulation results show that, the quadratic component of strip crown decreases nearly linearly with the increase of the work roll bending force, when the shifting value of intermediate roll is determined by the rolling process. From the first pass to the fifth pass of reversing rolling process, the crown controllability of bending force is gradually weakened. Base on analyzing the relationship among the main factors associated with roll-bending force in reversing multi-pass rolling, such as strip width and rolling force, a preset mathematic model of bending force is developed by genetic algorithm. The simulation data demonstrate that the relative deviation of flatness criterions in each rolling pass is improved significantly and the mean relative deviation of all five passes is decreased from 25.1% to 1.7%. The model can keep good shape in multi-pass reversing cold rolling process with the high prediction accuracy and can be used to guide the production process.     

基于惩罚项的热连轧轧制规程多目标函数优化

为了解决传统热连轧负荷分配优化普遍采用约束方法进行求解时求解步骤繁琐、不容易获得最优解的问题,提出了一种惩罚函数算法.通过引入函数惩罚项,将多目标函数约束求解问题转化为无约束求解问题.建立了带有惩罚项的轧制力、板形、功率和温度的单目标函数,进而采用线性加权求和法建立了综合多目标函数.利用Nelder和Mead单纯形解法则进行求解,简化了求解的步骤,最终得到了兼顾轧制力平衡、板形最优及温度合理的负荷分配方案.实际应用效果表明,与传统负荷分配方式相比,基于多目标优化得到的轧制规程更符合实际生产要求,具有良好的应用前景.     

板带钢头部翘曲的有限元分析

为了减轻轧件头部翘曲给轧制过程带来的影响,根据现场轧制工艺,采用弹塑性有限元法建立了三维非对称轧制有限元模型。利用该模型分析热轧板带钢生产过程中轧件头部翘曲的产生机理,并研究了不同轧制工艺下的辊速比、上下表面温差、不同摩擦系数对轧件头部翘曲的影响规律。结果表明,随着压下量的增大,轧件头部翘曲量的增大趋势减缓,采用不同的配辊方案（异径比）可控制其头部翘曲的现象。     

Analysis of bending on the front end of sheet during hot rolling

The analysis of bending in finishing rolling was performed. An asymmetrical rolling force model was established, and the upper and lower neutral points were determined. Thc bending which resulted from the asymmetrical rolling force at the roll gap was studied and related flexibility equations were proposed according to elastic mechanics. Moreover, material mechanics was used to analyze the effects of temperature difference and self-weight on the bending out of the roll gap, and the flexibility equations were constructed. The main factors on bending were summed up, and the bending rule in the rolling could be obtained. In addition practical calculation was made with the production data of ribbon steel from Laiwu Iron ＆ Steel Group Co. Ltd.     

基于余弦速度场的厚板轧制力能参数建模

为建立一个预测精度可靠的轧制力模型,根据轧件变形时金属流动的特点提出了一个余弦速度场,并基于该速度场进行了相应的能量解析。该速度场能够严格满足体积不变条件、出入口速度边界条件以及几何方程,较好地满足了运动许可条件。建模过程中,基于分矢量内积加和法导出了轧制内部变形功率,解决了非线性Mises比塑性功率带来的积分问题。同时,基于该速度场也导出了摩擦功率、剪切功率的数学表达式。在此基础之上,依据刚塑性变分原理获得了轧制力能参数的解析模型。利用国内某厂现场轧制数据对建立的轧制力模型进行了验证。结果显示,各道次轧制力预测值与实测值的误差均在7.55%以内,具有较高的精度。将所建模型与经典的Sims模型和Tselikov模型进行了对比,也显示了较好的优越性。此外,为了研究厚板轧制过程中的参数变化规律,本文也先后分析了压下率、形状因子、摩擦因子、径厚比、轧辊半径对应力状态系数和中性点位置的影响。     

冷轧带钢缺陷表面形状恢复新算法

为改善冷轧带钢表面缺陷分类识别性能,提出基于从阴影恢复形状原理的表面缺陷三维重构算法． 针对表面缺陷检测系统的光路设计,提出一种改进的Oren-Nayar漫反射模型,结合透视投影模型推导出相应 的反射图方程,利用基于高阶Lax-Friedrichs汉密尔顿函数和牛顿迭代相结合的快速扫描算法完成了该方程 的求解,实现表面缺陷三维信息的提取．利用合成图像和表面缺陷图像进行三维重构实验,结果表明该算法 重构精度高,验证了改进光照模型的正确性．该三维重构算法能够有效地提取冷轧带钢表面缺陷三维信息, 有助于提高表面缺陷分类识别性能     

Backup roll contour of a SmartCrown tandem cold rolling mill

SmartCrown was a new system developed by VAI for improving the strip profile and flatness control first applied in 1700mm tandem cold rolling mills at Wuhan Iron & Steel (Group) Corporation (WISCO). After tracing and testing, the application of the conventional crown backup roll matching the SmartCrown work roll of the production mill led to heavy and nonuniform wear, and the edge spalling of the backup roll often occurred. A 3-dimension finite element model of roll stacks was established, which was used to analyze the above-mentioned problems, and it was found that the main reason was the highly nonuniform contact pressure distribution between the work roll and the backup roll. A new FSR (flexible shape backup roll) was developed and applied in 1700mm tandem cold rolling mills. A lot of good actual effects of FSR, such as evident improvement in profile and flatness of strips,non-occurring edge spalling, wear uniform, and remarkable decrease in roll consumption were validated by long-term industrial applications.     

Industrial shape detecting system of cold rolling strip

A high-precision shape detecting system of cold rolling strip is developed to meet industrial application, which mainly consists of the shape detecting roller, the collecting ring, the digital signal processing (DSP) shape signal processing board and the shape control model. Based on the shape detecting principle, the shape detecting roller is designed with a new integral structure for improving the precision of shape detecting and avoiding scratching strip surface. Based on the DSP technology, the DSP shape signal processing circuit board is designed and embedded in the shape detecting system for the reliability and stability of shape signal processing. The shape detecting system was successfully used in Angang 1 250 mm HC 6-high reversible cold rolling mill. The precision of shape detecting is 0.2 I and the shape deviation is controlled within 6 I after the close loop shape control is input.