A Multi-stage Heuristic Algorithm for Matching Problem in the Modified Miniload Automated Storage and Retrieval System of E-commerce

E-commerce, as an emerging marketing mode, has attracted more and more attention and gradually changed the way of our life. However, the existing layout of distribution centers can＇t fulfill the storage and picking demands of e-commerce sufficiently. In this paper, a modified miniload automated storage/retrieval system is designed to fit these new characteristics of e-commerce in logistics. Meanwhile, a matching problem, concerning with the improvement of picking efficiency in new system, is studied in this paper. The problem is how to reduce the travelling distance of totes between aisles and picking stations. A multi-stage heuristic algorithm is proposed based on statement and model of this problem. The main idea of this algorithm is, with some heuristic strategies based on similarity coefficients, minimizing the transportations of items which can not arrive in the destination picking stations just through direct conveyors. The experimental results based on the cases generated by computers show that the average reduced rate of indirect transport times can reach 14.36% with the application of multi-stage heuristic algorithm. For the cases from a real e-commerce distribution center, the order processing time can be reduced from 11.20 h to 10.06 h with the help of the modified system and the proposed algorithm. In summary, this research proposed a modified system and a multi-stage heuristic algorithm that can reduce the travelling distance of totes effectively and improve the whole performance of e-commerce distribution center.

Vehicle Ride Comfort Based on Matching Suspension System

The existing investigations of vehicle ride comfort mainly include motion characteristics analysis based on creating a multi-body dynamic simulation model,and the parameters analysis to improve the suspension control for the target.In the study of creating multi-body dynamics simulation models,there is usually without considering calibration and test verification,which make it difficult to ensure the production of engineering.In the study of improving the suspension control parameters for the target,there is a lack of systematic match about comfortable and human characteristics,so it is difficult to implement in the field of driving and leading the vehicle design.In this paper,based on the different characteristic of suspension system that effects on the vehicle ride comfort, according to the suspension system dynamic mechanism,the research methods of vehicle road test,bench test and CAE simulation is used,at the same time,several sensitivity analysis of vehicle ride comfort related to suspension stiffness and damping and speed is made. As a result,the key suspension systematic parameters are given that have important impact on vehicle ride comfort.Through matching parameters,a calibration analysis of suspension system based on human comfort is obtained.The analysis results show that the analysis methods for the design target of making the vehicle with best comfort are effective.On the basis of the theory study,five suspension parameter matching principles are explored to promise the vehicle with perfect ride comfort,which also provide theoretical basis and design methods for the passenger car best match of suspension system stiffness and damping.The research results have the promotional value of practicability and a wide range of engineering application.

Controller design for stochastic nonlinear systems with matched conditions

This paper is concerned with the global boundedness problem for a class of stochastic nonlinear systems with matched conditions. The uncertainties in the systems are due to parameter variations and external stochastic disturbance. Only the matched conditions and the possible bound of the uncertainties are demanded. Based on the stochastic Lyapunov stability theory, an explicit controller is constructed in the gradient direction, which renders responses of the closed-loop systems be globally bounded in probability. When the systems degrade to linear systems, the controller becomes linear. Illustrative examples are given to show the effectiveness of the proposed method.

燃料电池增程式动力系统能量管理策略研究

以某款纯电动客车为研究对象,以增加车辆续驶里程为目的,提出燃料电池增程式混合动力系统结构,根据性能指标对动力系统各部件进行匹配计算和选型.提出了开关/功率跟随式能量管理策略,基于Cruise和Simulink分别搭建了整车动力系统模型和燃料电池及能量管理策略模型并进行联合仿真.结果表明,采用文中提出的能量管理策略车辆经济性相对于开关式和能量跟随式两种控制策略分别提高62%和31%,续驶里程相对于该两种控制策略分别提高41%和18%.

Stability analysis and controller design of T-S fuzzy systems with time-delay under imperfect premise matching

The issue of the stability and controller design of Takagi-Sugeno（T-S） fuzzy control systems with time-delay is investigated under imperfect premise matching when the T-S fuzzy time-delay model and fuzzy controller do not share the same membership functions.A new stability criterion which contains the information of membership functions is derived.The new stability criterion is less conservative,and enhances the design flexibility.Two numerical examples are presented to illustrate the conservativeness and effectiveness of the proposed method.

基于FPGA的小目标识别分类系统的设计与实现

为了提高小目标识别和分类的实时性,同时降低识别系统的资源消耗,本文提出了一种简易、高效的现场可编程门阵列(Field Programmable Gate Array,FPGA)小目标识别分类系统。该系统首先通过图像预处理消除图像噪点,并采用并行计算提升系统实时性。然后将处理后的图像与模板进行匹配计算得到识别结果,设计的模板匹配电路具有较小的硬件复杂度和较快的处理速度。实验结果表明,本文所提出的识别系统在680×480图像分辨下,可达137.5帧/s的处理速度,实时性强,同时仅消耗了9个块随机存储器(Block Random Access Memory,BRAM)和2个数字信号处理器(Digital Signal Processor,DSP),硬件资源消耗较少,在处理小目标识别和分类问题上有较好的实用价值。

Resource Allocation in D2D-Aided High-Speed Railway Wireless Communication Systems： A Matching Theory Approach

With the rapid deployment of high speed railway(HSR) worldwide,both safety operation and comfort experience can be desired to evolve into a future era of intelligent transportation system.To eliminate boredom and provide entertainment for passengers,an intranet for internal communications among passengers named as onboard social network system(SNS) is needed.In this paper,the latest progress in HSR network architectures and technology building blocks are discussed to enable the implementation of the SNS.Meanwhile,based on the device-to-device(D2 D) communication technology for proximal information interaction,SNS can be efficiently facilitated.A dynamic resource allocation algorithm is proposed to maximize the total utility of the onboard SNS,which is solved with the matching theory method.Simulation results verify the convergence and efficiency of the proposed algorithm.

电动装载机转向系统电液流量匹配控制策略

针对电动装载机优先型流量放大转向系统单动工况下节流损耗严重的问题,提出了一种电液流量自适应匹配的节能型控制策略。首先,介绍了优先型流量放大转向系统工作原理;其次,建立转向系统能量损失模型;然后,提出转向系统电液流量匹配控制策略,实现液压泵输出流量与转向系统需求流量的匹配,并构建液压泵流量非线性映射补偿模型,提升流量控制精度;最后,利用AMESim软件搭建系统仿真模型,与原系统对比仿真分析。结果表明:改进后系统流量损耗降低62.68%,能量损耗减少65.26%,节能效果显著,为电动装载机的推广应用奠定基础。

双目立体视觉下破损黑陶三维重建方法仿真

在三维重建过程中,由于受环境光线变化、物体透明度、遮挡等因素影响,导致重建结果不准确或不完整,使得视觉效果较差。为了提高三维重建精度,提出一种基于双目立体视觉的破损黑陶三维重建方法。通过转换世界-相机-图像-像素坐标系,标定双目立体视觉相机内外参数,引入最小生成树方法立体匹配左右图像对,计算图像像素绝对强度、梯度、匹配截断值对黑陶重建曲面平滑度的影响,得到连续稠密的视差图,使用最小二乘曲线拟合法平滑处理黑陶三维点云数据,将游离在曲面外的点映射到曲面中,通过三角剖分实现破损黑陶三维表面重建。实验结果表明,所提方法能够有效提高重建后黑陶表面平滑度,且重建结果尺寸精准,拟合度高。

任务匹配系统中高效可撤销属性加密方案

针对传统任务匹配系统中数据处理存在的安全隐私和成本开销问题,提出了一种适用于资源有限系统的高效可撤销外包密文策略属性加密方案.通过将传统的加密分为用户离线和在线加密阶段两部分实现快速加密,并将密文外包给云服务器再与区块链建立联系以降低用户计算成本,最后利用变色龙哈希函数更新用户私钥进行属性撤销和用户撤销两类细粒度撤销.最后通过实验表明,该方案与现有可撤销属性加密方案相比,可以抵御密钥泄露和共谋攻击,且具有更低的时间开销.

基于声全息法和单目视觉技术的柴油机噪声可视化实现

柴油机属于多噪声耦合动力装置,其噪声的识别和控制是内燃机研究领域的难点。为实现柴油机噪声的可视化,本研究结合了近场声全息法与单目视觉技术,开发了基于Labview的声像匹配模块,测试系统人机界面友好,并通过已知声源试验验证了声像匹配模块的正确性。将验证后的测试系统应用于高压共轨柴油机对主/次推力侧声源进行识别,结果表明:在大气压力为80kPa、转速为1800r/min的最大扭矩工况下,主推力侧出现较大辐射噪声的位置为中冷器进气管、曲轴定时齿形带轮、排气管、脚架和涡轮增压器等;次推力侧辐射噪声峰值出现在起动机位置。

双驱动射频负氢离子源匹配网络设计与实验研究

随着磁约束聚变实验装置对中性束注入器的输出束流强度与脉冲时间的要求越来越高,开展高功率大面积射频离子源的研究迫在眉睫。为了实现大面积、高密度均匀等离子体放电,基于多驱动射频离子源的设计是当前的发展趋势,而阻抗匹配网络是射频功率源将最大功率输送至线圈并耦合至等离子体的关键,故对其结构设计和调谐特性的研究是不可或缺的。基于前期在单驱动射频离子源的研究基础上,结合双驱动射频离子源的放电需求,开展了双驱动阻抗匹配网络优化结构的设计与分析,通过实验中对匹配网络的调谐,成功实现了140 kW高功率和25 kW/1 000 s长脉冲的稳定运行。随后在等离子体稳定放电的基础上研究了两个驱动器之间的功率分配均匀性问题,实验结果表明了该匹配网络的优化设计合理可行,上下驱动器的射频功率分配基本均匀。

公共文化服务融入学前教育的可及性研究——基于广州市的样本

公共文化服务已经成为我国文化建设的重要内容和战略工程,而可及性是评价公共文化服务体系与其服务对象“适合度”的概念。本研究基于737名广州市幼儿园教师和行政人员的调研数据,建构了包含可获得性、可接近性、可接受性和可适合性四个维度的可及性评价框架,分析和评价公共文化服务体系与幼儿园师生需求及文化服务利用行为间的适合性。研究发现:公共文化服务机构与幼儿园供需双方均认可公共文化服务的教育价值,但公共文化服务职能未得到充分发挥,公共文化服务融入学前教育的可及性总体有待提升。其中,可获得性和可接近性是现阶段影响公共文化服务融入学前教育的基础条件;检索公共文化服务资源能力弱、缺乏实践运用能力成为制约幼儿园运用公共文化服务的重要原因。公共文化服机构扩能提质增效且提供精准供给,推动幼儿园常态化关注与运用公共文化服务,是提升公共文化服务与幼儿园师生需求间适合性的可选路径。

改进ORB-SLAM在嵌入式系统中实现

针对飞行载体的实时ORB-SLAM实现问题,提出一种在嵌入式系统实现的改进ORB(oriented FAST and rotated BRIEF)单目视觉里程计算法。算法首先对输入图像进行灰度化、高斯滤波预处理实现简化运算和图像去噪,考虑到算法移植及在嵌入式系统实现,将图像预处理和ORB图像特征提取与匹配等功能封装为IP(intellectual property)核,布置到硬件系统中,提高特征提取与匹配的速度和正确率,保证位姿估计实时性。搭建ZYNQ嵌入式系统,开展对比实验,实验结果表明:改进后的算法特征点匹配率提高了3.78倍,特征提取与匹配的耗时缩短为原来的1/8,处理图像的帧率可以达到19 fps,满足实时性要求。

基于深度学习语义匹配的通用智能问答系统的设计与实现

FAQ问答系统有着广泛的实际应用场景,但传统问答系统的搭建通常需要将相关领域的知识转化为一系列的规则和知识图谱,且构建过程重度依赖人力,换个场景或用户都需要大量的重复劳动。针对上述问题并结合Bert模型和向量搜索引擎Faiss,本文设计了一种基于深度学习语义匹配的FAQ问答系统的解决方案,介绍了系统的工作原理和设计流程,可以方便快速地搭建面向特定领域的问答系统,有效地减少了文本预处理的过程,实现了秒级的查询响应。系统测试发现,可以很好地对用户的查询进行语义匹配,并返回正确的答案,为构建各种问答系统提供了一种通用的解决思路。

燃料电池氢气流量控制系统变负载匹配设计与仿真

针对车载质子交换膜燃料电池供氢系统负载工况多变时的氢气流量控制问题,提出一种基于比例减压阀与流量控制阀的氢气流量负载匹配控制系统架构与方法。建立了从高压储氢瓶至燃料电池堆的供氢系统整体模型,基于该模型设计了比例减压阀、流量控制阀与氢气循环泵的控制策略,并就某一型号电堆的变负载工况对系统模型与控制策略进行仿真验证。结果表明:电堆阳极压力可快速跟踪给定压力,响应时间约2~3s;氢气流量可适应负载变化需求,其瞬时超调量与压力响应速度成正相关;稳态时氢气利用率维持在95%以上,供氢过量比维持在1.27以上,供气氮含量维持在5%以下,满足电堆性能需求。

透平风机与纸机真空系统的匹配设计方法

本课题主要在湿纸幅流阻特性分析的基础上,探讨了透平风机与湿纸幅的气动匹配特性,并以实际生产线技改为例,介绍了应用透平风机改进真空系统的相关设计准则。

面向农机产品服务供应链采购模式匹配评价

随着制造业数字化转型和农机产品服务供应链的应用,突显出农机制造企业产品零部件采购模式,在选择匹配过程中存在主观性与模糊性的问题,提出一种基于物元可拓优度结合可拓层次分析法和CRITIC综合赋权法的采购模式匹配评价方法。从农机制造企业产品自身特征和产品服务供应链影响因素为切入点,构建产品服务供应链视角下的农机制造装备采购模式匹配评价体系,并通过关联函数计算,得到采购模式综合优度排序和单项指标的关联度对比,输出最优采购匹配模式和模式识别度。结果表明,最优采购模式匹配度为0.118,所对应的模式可以作为产供销阶段的核心采购模式。实例计算表明,建立的评价模型与企业匹配度很高,该方法将定性预测和定量决策结合起来,可以为农机制造企业的产品采购模式提供系统科学的匹配工具。

考虑机组弹性的双层隔振系统刚度匹配方法

为解决柴油发电机组对不同类型和功率发电机的连接套与隔振系统刚度匹配问题,提出以广义弹性力做功为基础的能量解耦法来量化刚度匹配对双层隔振系统固有特性的影响.基于某内燃动力总成双层隔振系统建立3自由度和18自由度动力学模型进行分析.结果表明:3自由度模型能够反映系统耦合的主要特点,机组弹性模态频率与低阶刚体振动模态频率比大于2.96时可以降低刚体振动对弹性模态的影响;考虑惯性耦合和弹性耦合后,18自由度模型对应的频率比应大于4.10才可以显著降低该振动耦合.同一柴油机匹配不同惯性参数的发电机,均可参考小惯性参数发电机隔振设计时对应的频率比和刚度比进行双层隔振系统刚度匹配.