箱装电子仪器安全跌落冲击数值模拟方法研究

为正确评估跌落冲击对箱装电子仪器可靠性的影响,确定了合理的包装参数和设计流程,科学指导运输与试验,分别采用理论分析和有限元计算方法对箱装电子仪器垂直跌落的情况进行了仿真,得到了垂直跌落条件下电子仪器最大加速度和最大位移随跌落高度与缓冲垫弹性模量变化的规律。结合产品脆值,确定了产品储运过程中的最大堆垛高度,并得到了合理的包装设计流程,从而为有效指导产品包装设计、实体试验和储运安全提供了理论依据。     

考虑库存信息的钢管批量计划优化算法

在考虑库存信息的基础上对钢管批量计划优化问题进行研究,建立了批量计划轧制位置与垛位钢坯多对多关系的批量计划模型,实现对倒垛次数的优化。结合问题特征,设计了一种基于钢坯连续倒垛的两阶段批量计划优化算法：第1阶段,确定当前最优钢坯,进而搜索同垛位上的下层钢坯,匹配最佳的连续轧制钢坯;第2阶段,针对每个轧制位置搜索垛位上的连续轧制钢坯,改进第1阶段的解。通过基于实际生产数据的实验验证,相对经典启发式算法,倒垛次数显著降低,算法和模型是可行且有效的。     

基于FlexSim 的军队自动化立体仓库货位优化研究

为提高军队自动化立体仓库出货速度和运行稳定性,提出了在堆垛机闲时对货位进行以分类存储L 形分区为导向的再分配优化设计。根据用户需求,程序自动生成分类存储的L 形分类存储货位分区信息,并调用堆垛机对在存货品逐一判断、搬运,让所有货品按照L 形区域排列,完成货位优化。利用FlexSim 软件对具体实例进行了仿真,结果表明,优化后的货位能较大程度地提高仓库的输出效率。     

求解集装箱堆场堆垛问题的约束满足算法

集装箱堆垛问题普遍存在于港口码头堆场作业管理中,是在集装箱数目已知的前提下,要求满足交货期限制、重量限制以及垛位高度限制等约束条件,目标是实现占用垛位数最少。通过问题分析,将其归结为一类带顺序约束的装箱问题,并建立了约束满足优化模型,设计了嵌入经典装箱启发式原则的约束满足求解算法。为了验证模型和算法的可行性和有效性,根据某集装箱码头堆场的实际生产情况构造测试算例,实验结果表明,该算法对于实现垛位数最小化、求解复杂约束下的大规模堆场问题较现有的装箱启发式有一定程度的改善。     

基于Cape Pack的军用物资单元包装优化研究

探讨了现代后勤对军用物资单元包装的要求,介绍了Cape Pack包装决策支持软件的主要功能,提出了基于该软件对军用物资单元包装优化的设计方案,最后通过案例演示了优化设计过程并对其结果进行分析,为军用物资单元包装优化提出了新的思路。     

立体仓库库位号与堆垛机运作效率关系的探讨

根据国内自动化立体仓库物料的主要存放模式，在分析堆垛机自动存取方式的基础上，说明库位号与堆垛机动作的关系，分析影响堆垛机动作效率的各种因素，提出库位优化的思想，并根据具体参数通过编程给出几种优化分布的库位号，最后对优化库位及传统库位进行仿真比较并分析存在的问题。     

综合性成品仓库设计优化方案

文章论述了高架仓库具有存储多、自动化程度高、便于管理、容易作业、高效率等巨大的优越性,是现代物流系统的发展趋势。从现有库存数据分析确定优化原设计方案,分析堆垛机作业能力及可行性论证,介绍货位自动化管理方法,以及设计方案比较,分析投资预算,评审确定拟新建成高架仓库和一般仓库混合的综合性成品仓库。     

箱装弹药堆码仿真设计与优化算法

为满足弹药仓库堆码的实际需求,通过对箱装弹药储存管理特点和堆码基本原理的分析,提出了数字化堆码管理方案,应用Maya软件对洞库环境、设备和包装箱进行了三维数字建模,设计了堆码方案的交互界面,给出了弹药堆码方案的算法设计。     

基于Flexsim的自动化立体仓库出入库仿真与优化

对某制造企业的自动化立体仓库出入库进行了仿真和优化。首先在对该仓库的实际作业进行测录的情况下,收集了各类仿真对象的数据并记录了该自动化立体仓库的出入库及存取作业程序;然后使用Flexsim软件进入仿真,并对仿真运行数据进行分析,写出相应的改善方案;最后再使用Flexsim仿真软件对优化后的仓库进行仿真建模,与优化前的仿真模型输出的数据进行对比分析。结果表明,各个操作台的利用率都比优化前的提高了10%~15%,巷道堆垛机的利用率提高了3%,高层货架货位库存量、货位利用率得到明显提高,各个缓存区的堆积现象明显减少,从而验证了优化方案的可行性。     

20kg铝锭连续铸造机堆垛机改进

20kg铝锭铸造机组为一普通铝锭连续铸造的自动化生产线。主要由铸造机、冷运机、堆垛机、成品运输机5个部分组成，整个机组的特点是连续运行。20kg重的成品锭按规定的排列形状自动地堆成垛，铸锭、冷却及堆垛等工序均为自动化操作，堆垛后采用气动打捆机对铝锭进行打捆，然后入库。     

Designing a block stacked warehouse for dynamic and stochastic product flow: a scenario-based robust approach

The problem considered in this paper is motivated from a real life case. Conventional models in designing block stacked warehouse assume uniform and deterministic inflow and outflow of products in specific quantities and time intervals. These assumptions would lead to underestimation of space requirement for the case. Also, the possibility of leasing additional warehouse space during seasonal spikes was found to be unexplored in block stacking design literature. In this study, we develop a scenario-based model to address the decisions of warehouse size, lane depth and hiring of temporary additional warehouse capacity when flow of products is stochastic and dynamic in nature. A sequential decision model is presented with future operating scenarios assumed to branch out in the form of a tree. On comparison with conventional block stacking design methods, the model is found to provide robust solution in stochastic and dynamic environments in terms of risk reduction and infeasibility avoidance. Further, the model gives additional flexibility to the designer to trade-off model and solution robustness with predicted cost.     

基于PLC的自动包装码垛生产线的研究与设计

目的 为了提高固体颗粒物料的包装及包装袋码垛效率,降低企业工人的劳动强度。方法 以西门子PLC S7-1200为控制核心,结合数字输入SM321、数字输出SM322等模块,设计一套自动包装码垛生产线,用于粮食、化肥等物料的自动包装和码垛。通过设计伺服电机驱动、传感器输入模块、触摸屏人机交互界面等来实现对生产线的自动控制。结果 在完成生产线固体物混料装置、包装袋称量装置以及码垛机器人的基础上,进行化肥的包装实验,记录了包装袋称量误差以及码垛的中心误差,分析发现中心抓取误差小于0.2 mm。结论 该生产线系统可靠性强、包装码垛精度高,能够大大提高包装和码垛效率,具有很大的市场应用前景。     

Optimising space utilisation in block stacking warehouses

Block stacking storage is an inexpensive storage system widely used in manufacturing systems where pallets of stock keeping units (SKUs) are stored in a warehouse at the finite production rates. However, determining the optimal lane depth that maximises space utilisation under a finite production rate constraint has not been adequately addressed in the literature and is an open problem. In this research, we propose mathematical models to obtain the optimal lane depth for single and multiple SKUs where the pallet production rates are finite. A simulation model is used to evaluate performance of the proposed models under stochastic uncertainty in the major production parameters and the demand.     

Geometry and Stacking Sequence Effect on Composite Spinnaker Pole's Stiffness: Experimental and Numerical Analysis

Composite materials are widely employed in sailing sports, a possible application is for the mast pole or other sail poles. In the paper the attention is focused on the spinnaker poles mechanical performances; in particular the focus is on axial and ring compressive properties of three different carbon fibre/epoxy resin spinnaker poles, to investigate both the diameter and stacking sequence effect on the mechanical performance of the structure. Starting from the stacking sequence used in the production of a particular spinnaker pole, the effect of a lamina at 0° in the middle of wall thickness is investigated with the purpose to obtain a more stiff structure. Moreover to test the proposed stacking sequence on different size products, a prototype with lower diameter is realized. To properly evaluate axial and ring stiffness, axial compression test and ring stiffness one are performed. Then a numerical model is developed to support the design of the finished product: A simple and versatile numerical analysis (FEA with software ANSYS), by simulating ring stiffness and pull-direction compression tests, is carried out in elastic regime. Such model should be suitable for designing and/or verifying the mechanical performance of pole structures, even though differing from those above described, for materials, geometry and stacking sequence.     

Reliable Piezoelectricity in Bilayer WSe2 for Piezoelectric Nanogenerators

Recently, piezoelectricity has been observed in 2D atomically thin materials, such as hexagonal‐boron nitride, graphene, and transition metal dichalcogenides (TMDs). Specifically, exfoliated monolayer MoS₂ exhibits a high piezoelectricity that is comparable to that of traditional piezoelectric materials. However, monolayer TMD materials are not regarded as suitable for actual piezoelectric devices due to their insufficient mechanical durability for sustained operation while Bernal‐stacked bilayer TMD materials lose noncentrosymmetry and consequently piezoelectricity. Here, it is shown that WSe₂ bilayers fabricated via turbostratic stacking have reliable piezoelectric properties that cannot be obtained from a mechanically exfoliated WSe₂ bilayer with Bernal stacking. Turbostratic stacking refers to the transfer of each chemical vapor deposition (CVD)‐grown WSe₂ monolayer to allow for an increase in degrees of freedom in the bilayer symmetry, leading to noncentrosymmetry in the bilayers. In contrast, CVD‐grown WSe₂ bilayers exhibit very weak piezoelectricity because of the energetics and crystallographic orientation. The flexible piezoelectric WSe₂ bilayers exhibit a prominent mechanical durability of up to 0.95% of strain as well as reliable energy harvesting performance, which is adequate to drive a small liquid crystal display without external energy sources, in contrast to monolayer WSe₂ for which the device performance becomes degraded above a strain of 0.63%.     

Modulating the Interlayer Stacking of Covalent Organic Frameworks for Efficient Acetylene Separation

Controllable modulation of the stacking modes of 2D (two-dimensional) materials can significantly influence their properties and functionalities but remains a formidable synthetic challenge. Here, an effective strategy is proposed to control the layer stacking of imide-linked 2D covalent organic frameworks (COFs) by altering the synthetic methods. Specifically, a modulator-assisted method can afford a COF with rare ABC stacking without the need for any additives, while solvothermal synthesis leads to AA stacking. The variation of interlayer stacking significantly influences their chemical and physical properties, including morphology, porosity, and gas adsorption performance. The resultant COF with ABC stacking shows much higher C₂H₂ capacity and selectivity over CO₂ and C₂H₄ than the COF with AA stacking, which is not demonstrated in the COF field yet. Furthermore, the outstanding practical separation ability of ABC stacking COF is confirmed by breakthrough experiments of C₂H₂/CO₂ (50/50, v/v) and C₂H₂/C₂H₄ (1/99, v/v), which can selectively remove C₂H₂ with good recyclability. This work provides a new direction to produce COFs with controllable interlayer stacking modes.     

基于多智能体强化学习的自动化电力仓库货位优化

自动化仓库的货位优化是提高仓库效率的重要途经之一。本文针对电力仓库货位优化问题,采用基于多智能体强化学习的方法,提升优化效果。首先分析DDPG算法和MADDPG等算法的不足;然后在此基础上提出改进算法ECS-MADDPG及其模型。在该算法中,同时考虑当前时间点的即时奖励和未来奖励因素;最后利用电力物资的历史出入库数据,应用强化学习算法训练货位优化模型。研究表明,与MADDPG、DDPG等算法相比,ECS-MADDPG拥有较高的稳定性和回报值。     

提高大型木包装箱堆码强度的侧立柱改进设计方法

结合材料力学的受力分析方法,以不同的底座形式及其对应的不同的包装箱尺寸为例,对包装箱分别承受均布载荷和集中载荷条件下的堆码强度进行受力分析,校核侧立柱的堆码强度,改进堆码强度的设计方法,为堆码强度的设计、分析研究提供参考依据.     

High‐Stacking‐Density,Superior‐Roughness LDH Bridged with Vertically Aligned Graphene for High‐Performance Asymmetric Supercapacitors

The high‐performance electrode materials with tuned surface and interface structure and functionalities are highly demanded for advanced supercapacitors. A novel strategy is presented to conFigure high‐stacking‐density, superior‐roughness nickel manganese layered double hydroxide (LDH) bridged by vertically aligned graphene (VG) with nickel foam (NF) as the conductive collector, yielding the LDH‐NF@VG hybrids for asymmetric supercapacitors. The VG nanosheets provide numerous electron transfer channels for quick redox reactions, and well‐developed open structure for fast mass transport. Moreover, the high‐stacking‐density LDH grown and assembled on VG nanosheets result in a superior hydrophilicity derived from the tuned nano/microstructures, especially microroughness. Such a high stacking density with abundant active sites and superior wettability can be easily accessed by aqueous electrolytes. Benefitting from the above features, the LDH‐NF@VG can deliver a high capacitance of 2920 F g^?1 at a current density of 2 A g^?1, and the asymmetric supercapacitor with the LDH‐NF@VG as positive electrode and activated carbon as negative electrode can deliver a high energy density of 56.8 Wh kg^?1 at a power density of 260 W kg^?1, with a high specific capacitance retention rate of 87% even after 10 000 cycles.