板坯热轧计划编制的优化模型与算法

针对热轧计划编制问题,考虑不兼容钢种因素,给出了主体材的热轧规程,并在优化目标中引入最小化出炉温度跳跃惩罚,建立了多目标数学模型。结合模型特征设计了单亲遗传算法,并对算法的基本参数和目标函数的惩罚值进行了深入探讨,以增强算法的适用性和求解效率;提出了热轧计划数和不可行热轧计划解的处理策略,以提高算法的求解性能。以钢种、规格和轧制工艺优化的订单和库存数据为初始数据,考虑有/无不兼容钢种两种情况进行仿真实验,实验结果表明,所提模型和算法能够有效解决不兼容钢种热轧计划问题,编制的热轧计划具有准确性。     

考虑工艺路线的热轧无缝钢管订单排程方法

为解决热轧无缝纲管在多工艺路线下的订单排程问题,将工艺路线因素引入热轧钢管订单排程中,建立了以合理的工艺路线切换、最小化机器设备调整和准时制生产为优化目标的约束满足模型,并设计了求解算法。该算法根据模型特征,提出基于降序最佳适应的约束满足算法和基于约束的聚类算法,对订单进行整理并形成初始轧制计划;设计了两种批次交换搜索算法,分别对单日内及日间的初始轧制批次进行排程优化。通过基于实际订单数据的实验讨论了上述算法两两组合的求解效果和各自的适用情况,验证了模型和算法的可行性和有效性。     

基于仿真优化的加热炉—热轧区间重调度

为实现钢铁企业的生产连续性、成本降低等优化目标,在考虑加热炉、连铸机生产的工艺要求、订单交货期和产能的基础上,建立了加热炉—热轧区间生产调度模型,并利用非支配排序遗传算法对其进行求解。当加热炉或热轧机出现故障时,利用局部重调度重排策略,实现了加热炉—热轧区间的重调度。为减少随机因素的影响,可对染色体进行多次独立仿真,取其平均值返回给优化器。基于实际生产数据验证了该模型和方法的适用性和可行性。     

基于HPCVRP的多目标热轧计划排程研究

针对目前钢铁热轧计划排程中未考虑板坯间电耗变化而造成能耗较高问题,建立基于混合奖金收集模式车辆路径问题(Hybrid Price Collect Vehicle Routing Problem,HPCVRP)的多目标优化模型。针对最小轧制计划数量、工艺规程、吨钢电耗等目标,采用过滤器方法处理热轧模型约束,通过改进的可行性优先粒子比较准则进行最优粒子选择,结合过滤器拥挤距离及拥挤向量机制控制外部档案数量并更新全局最优值,构建过滤器方法的多目标粒子群算法(Filter-MOPSO,FMOPSO),仿真结果表明可以获得良好的Pareto优化前端。最后与人工结果相比,所提算法和模型能够有效解决热轧计划排程问题,为热轧计划编制人员提供良好的决策支持。     

考虑多阶段多流向的冷轧生产计划模型及算法

针对冷轧生产流程多阶段库存和批次多流向的特点,在满足工艺约束的基础上建立了以合同超期和提前的总惩罚费用最小、中间库存量超出和不足的总惩罚费用最小并确保成品库成本最低为目标的多阶段多流向冷轧生产计划模型,采用改进的遗传算法进行求解。算法通过参数的合理设定,解决了交叉、变异概率在一定区间内取固定值、断点处函数值跳跃大和出现不合理值的问题,使两种概率可根据适应值进行自适应调整。以国内某冷轧企业为案例对模型和算法进行了验证,实验结果表明该冷轧生产计划模型能够保证合同交货期和降低库存成本。     

[供应链调度]分时电价和时变行程时间下的供应链调度

针对单机供应链调度问题,在生产计划和批次配送阶段分别考虑分时电价政策和时变行程时间。以总成本最小为目标建立混合整数规划模型,通过对模型的分析给出了最优解的性质,以此将模型分解为若干个批次的机器调度子问题。对于子问题优化,设计了子集划分启发式算法并证明了算法的最优性。对于主问题的优化,设计了自适应变邻域搜索算法。数值计算结果验证了模型和算法的有效性,证明了供应链集成调度能减少大量的能源消耗。     

多对多板坯倒垛问题的一种邻域搜索算法

为解决热轧生产计划中出现的板坯倒垛问题,建立了基于轧制位置与库内板坯多对多对应关系的问题模型,提出了一种新的邻域搜索算法。该算法考虑到轧制计划中的板坯规格组在库内垛位中连续堆放的特点,引入了Sequence邻域概念,使算法能够更好地利用问题的特征,并通过两阶段的寻优替换对问题进行求解。实验结果表明了所提模型和算法的可行性和有效性。     

分时电价和时变行程时间下的供应链调度

针对单机供应链调度问题,在生产计划和批次配送阶段分别考虑分时电价政策和时变行程时间。以总成本最小为目标建立混合整数规划模型,通过对模型的分析给出了最优解的性质,以此将模型分解为若干个批次的机器调度子问题。对于子问题优化,设计了子集划分启发式算法并证明了算法的最优性。对于主问题的优化,设计了自适应变邻域搜索算法。数值计算结果验证了模型和算法的有效性,证明了供应链集成调度能减少大量的能源消耗。     

面向多种生产工艺的冶铸轧一体化批量计划优化

考虑面向冷装、温装、热装和直轧等多种生产工艺的炼钢、连铸和热轧三阶段一体化批量计划优化问题,针对问题特点提出了一体化编制策略,并在此基础上建立了问题的约束满足模型.针对模型无优化目标和具有复杂工艺约束,及其求解过程具有NP难性质的特点,提出了将约束传播技术嵌入到聚类分析中的求解算法.通过源于钢铁企业实际生产数据的仿真实验结果表明了模型和算法的有效性.     

炼钢-连铸-热轧批量计划的约束满足算法

为解决轧制计划编制问题,研究了炼钢-连铸-热轧一体化生产批量计划,提出了基于约束满足的启发式算法.根据炼钢-连铸阶段批量计划约束条件,从轧制计划中提炼出炉次计划和浇次计划,同时提出启发式算法求解.在两个启发式算法的基础上,运用基于参数控制的策略,编制出前后工序协调一致的一体化批量计划.数据实验结果表明了该方法及算法的有效性.     

Minimal Realization of Linear Graph Models for Multi-physics Systems

An engineering system may consist of several different types of components,belonging to such physical"domains"as mechanical,electrical,fluid,and thermal.It is t...     

INTEGRAL EQUATION METHOD＇S APPLICATION IN HOLE-EDGE STRESS OF COMPOSITE MATERIAL PLATE WITH DIFFERENT SHAPED HOLES

The strength of composite plate with different hole-shapes is always one of the most important but complicated issues in the application of the composite material. The holes will lead to mutations and discontinuity to the structure. So the hole-edge stress concentration is always a serious phenomenon. And the phenomenon makes the structure strength decrease very quickly to form dangerous weak points. Most partial damage begins from these weak points. According to the complex variable functions theory, the accurate boundary condition of composite plate with different hole-shapes is founded by conformal mapping method to settle the boundary condition problem of complex hole-shapes. Composite plate with commonly hole-shapes in engineering is studied by several complex variable stress fimction. The boundary integral equations are founded based on exact boundary conditions. Then the exact hole-edge stress analytic solution of composite plate with rectangle holes and wing manholes is resolved. Both of offset axis loadings and its influences on the stress concentration coefficient of the hole-edge are discussed. And comparisons of different loads along various offset axis on the hole-edge stress distribution of orthotropic plate with rectangle hole or wing manhole are made. It can be concluded that hole-edge with continuous variable curvatures might help to decrease the stress concentration coefficient; and smaller angle of outer load and fiber can decrease the stress peak value.     

Non-monotonic material contrast in scanning ion and scanning electron images

30 keV Ga⁺ focused ion beam induced secondary electron (iSE) imaging was used to determine the relative contrast between several materials. The iSE signal compared from C, Si, Al, Ti, Cr, Ni, Cu, Mo, Ag, and W metal layers does not decrease with an increase in target atomic number Z₂, and shows a non-monotonic relationship between contrast and Z₂. The non-monotonic relationship is attributed to periodic fluctuations of the stopping power and sputter yield inherent to the ion–solid interactions. In addition, material contrast from electron-induced secondary electron (eSE) and backscattered electron (BSE) images using scanning electron microscopy (SEM) also shows non-monotonic contrast as a function of Z₂, following the periodic behavior of the stopping power for electron–solid interactions. A comparison of the iSE and eSE results shows similar relative contrast between the metal layers, and not complementary contrast as conventionally understood. These similarities in the contrast behavior can be attributed to similarities in the periodic and non-monotonic function defined by incident particle–solid interaction theory.     

Short-Term Relay Quality Prediction Algorithm Based on Long and Short-Term Memory

The fraction defective of semi-finished products is predicted to optimize the process of relay production lines, by which production quality and productivity ar...     

End-to-End Multiview Gesture Recognition for Autonomous Car Parking System

The use of hand gestures can be the most intuitive human-machine interaction medium.The early approaches for hand gesture recognition used device-based methods....     

Application of Feature Extraction through Convolution Neural Networks and SVM Classifier for Robust Grading of Apples

This paper proposes a novel grading method of apples,in an automated grading device that uses convolutional neural networks to extract the size,color,texture,an...     

分布动态载荷识别的抗噪处理

针对正交多项式频域法在用多种响应对矩形薄板进行载荷识别中抗噪性较差的问题,综合运用平均法、矩阵预处理和奇异值截断法等方法对之进行改善,并引入空间映射的思想,将该方法的应用范围拓展为复杂的模型.利用仿真算例,证实了该方法具有较好的抗噪性.     

基于MELTAC-N平台的核电厂安全级DCS环网研究与测试

针对工程实践中环网通讯相关问题的处理缺乏理论基础及国产化安全级DCS平台的开发缺乏成熟经验借鉴问题,对基于MELTAC-N平台核电厂安全级DCS环网的软硬件实现进行了研究。提出了安全级DCS环网双环网冗余设计、光切换开关设计等硬件设计方法,以及以RPR协议为基础,采用全数据收发策略的软件设计方法。在CPR1000安全级DCS平台上对安全级DCS环网的可靠性及实时性进行了评价,并进行了容错能力、响应时间及响应时间稳定性测试验证实验。结果表明,基于MELTAC-N平台安全级DCS环网软硬件设计具有较好的容错能力及响应时间稳定性。     

The laboratory simulation of abrasive wear

Abrasive wear has long been recognised as one of the most potentially serious tribological problems facing the operators of many types of plant and machinery; several industrial surveys have indicated that wear by abrasion can be responsible for more than 50% of unscheduled machine and plant stoppages. Locating the operating point of a tribological contact in an appropriate operational ‚map’︁ can provide a useful guide to the likely nature and origins of the surface degradation experienced in use, though care must be exercised in choosing the most suitable parameters for the axes of the plot. Laboratory testing of materials and simulations of machine contacts are carried out for a number of purposes; at one level for the very practical aims of ranking candidate materials or surface hardening treatments in order of their wear resistance, or in an attempt to predict wear lives under field conditions. More fundamentally, tests may be aimed at elucidating the essential physical mechanisms of surface damage and loss, with the longer term aim of building an analytical and predictive model of the wear process itself. In many cases, component surface damage is brought about by the ingress of hard, particulate matter into machine bearing or sealing clearances. These may be running dry although, more usually, a lubricant or service fluid is present at the interface. A number of standardised wear test geometries and procedures have been established for both two- and three-body wear situations, and these are briefly described. Although abrasive wear is often modelled as following an ‚Archard’︁ equation (i.e. a linear increase in material loss with both load and time, and an inverse dependence on specimen hardness) both industrial experience and laboratory tests of particularly lubricated contacts show that this is not always the case: increasing the hardness differential in an abrasively contaminated lubricated pair may not always reduce the rate of damage to the harder surface.     

ANGULAR DISTORTION ALLOWABLE VALUE AND ASSESS METHOD OF WELD ON COKE TOWER

A graph as the new engineering method for estimate the safety of bulging deformation of coke tower is proposed. Through stresses analysis of circumferential weld of coke tower and comparing the stresses produced by pressure with heat stress of steady state, residual stress, bending stress produced by both itself weight and wind loads, it showed that the stresses produced by pressure on the angle distortion are the main factor of equivalent stress of the combined stress. After comparing four kinds of stress controlling conditions, the relation to stress with depth of angular distortion, grade of curvature of angular distortion and half of region of angular distortion has been inferred. Graph of deformation allowable value of coke tower for different condition by angular distortion and half of region of angular distortion has been plotted. The five steps for its engineering use have been explained. The lighter the grade of curvature is, the larger of bulge allowance, may be, and the bigger of depth of angular distortion may pose too. For the coke tower with a popular structure of Dg 5 400 mm×28 mm, the result by graph is nearly more than the result of two formulas formed by other research, the error is less than 7.0%. But, the graph can be easily applied to different size of angular distortion.