A novel method of shrimp blanching by CO2 heat pump: Quality,energy, and economy analysis

To reduce the energy consumption of the shrimp blanching process and improve the economic value of the blanched product, a transcritical CO₂ heat pump blanching system (THPB system) was designed in this paper. The trends of astaxanthin were investigated at atmospheric pressure near boiling temperature, combined with the color and structural properties of shrimp samples, and the optimal blanching times of 270 s and 240 s were obtained at 90°C and 95°C, respectively. In contrast to the fuel blanching system (FB system) at 100°C, the annual standard coal consumption of the THPB system with 90°C blanching is decreased by 79%, and the annual operating cost can be saved by CNY 63,800, with a payback period of about 3.13 years.Industrial relevanceBlanching is one of the effective ways to prolong the shelf life of shrimp. However, the research on the blanching time and temperature of shrimp is not comprehensive. In addition, the traditional fuel blanching process has high energy consumption and pollution, and can no longer meet the quality requirements of the modern food processing industry. Heat pump has been shown to have better performance in food drying, but it is less used in blanching. The information presented in this study may provide other insights into food processing.     

An energy-saving nonlinear position control strategy for electro-hydraulic servo systems

The electro-hydraulic servo system (EHSS) demonstrates numerous advantages in size and performance compared to other actuation methods. Oftentimes, its utilization in industrial and machinery settings is limited by its inferior efficiency. In this paper, a nonlinear backstepping control algorithm with an energy-saving approach is proposed for position control in the EHSS. To achieve improved efficiency, two control valves including a proportional directional valve (PDV) and a proportional relief valve (PRV) are used to achieve the control objectives. To design the control algorithm, the state space model equations of the system are transformed to their normal form and the control law through the PDV is designed using a backstepping approach for position tracking. Then, another nonlinear set of laws is derived to achieve energy-saving through the PRV input. This control design method, based on the normal form representation, imposes internal dynamics on the closed-loop system. The stability of the internal dynamics is analyzed in special cases of operation. Experimental results verify that both tracking and energy-saving objectives are satisfied for the closed-loop system.     

Non-singular antiplane fracture theory within nonlocal anisotropic elasticity

In the present paper, the distributed dislocation technique is applied for the analysis of anisotropic materials weakened by cracks. Eringen's theory of nonlocal elasticity of Helmholtz type is employed. The non-singular screw dislocation within anisotropic elasticity is distributed to model cracks of mode III. The corresponding dislocation density functions are evaluated using the proper crack-face boundary conditions. The nonlocal stress field within a plane weakened by cracks is determined. The crack opening displacement is also discussed within the framework of nonlocal elasticity. The stress singularity of the classical linear elasticity is removed by the introduction of the nonlocal theory of elasticity. The general anisotropic case and the special case of orthotropic material are studied. The effect of material orthotropy is presented for a crack which is not necessarily aligned with the principal orthotropy direction.     

Wheel hub customization with an interactive artificial immune algorithm

With the transformation from traditional manufacturing to intelligent manufacturing, customer-oriented personalized customization has gradually become the main mode of production. Interactive algorithms determine the pros and cons of the solution via customers which can make customers better participants in the customization process. However, if the population size is expanded and the number of evolutionary iterations is too high, frequent interactions are likely to cause customer fatigue. This paper proposes an adaptive interactive artificial immune algorithm based on improved hierarchical clustering. This algorithm uses the improved hierarchical clustering algorithm to optimize generation of the initial antibodies and applies the affinity calculation method based on customer intention, adaptive crossover and mutation operators, and a multisolution reservation method based on hybrid selection strategy to the artificial immune algorithm. Via empirical research on the customized operational data of wheel hubs, the proposed method effectively solves the problem of customer fatigue, significantly improves the convergence speed of the algorithm and reduces the time cost.

     

单片机在木板自动剪切机中的应用

由于某厂生产各种规格木板的十多台设备专机,全靠人工手动操作的问题。这些设备与现在日益发展的工业自动化设备相比存在着很大的缺陷。本文利用AT89C51单片机进行控制,并在原设备工作台上加装一台三相异步电动机和一条木板送料传送带,使得工人不用在车间工作就可以控制整个生产过程。显著提高了企业生产效率,达到降低生产成本的效果。     

Multi-Scale Dilated Convolutional Neural Network for Hyperspectral Image Classification

基于多尺度空洞卷积神经网络的高光谱图像分类

郑姗姗¹,刘文¹,单锐¹,赵静一²,江国乾³,张智⁴

（1. 燕山大学理学院,河北 秦皇岛 066004;2. 燕山大学机械工程学院,河北 秦皇岛 066004;3. 燕山大学电气工程学院,河北 秦皇岛 066004;4. 北京航天研究所,北京 100094）

创新点说明：

1）将图像分割方法——空洞卷积用于卷积神经网络进行高光谱图像分类,提取更加广泛、抽象的图像特征。

2）构建基于多尺度空洞卷积神经网络的高光谱图像分类方法。搭建多尺度聚合结构,在每个通道中使用快捷连接和空洞卷积结构,有效提取图像特征,避免信息丢失。

研究目的：

针对图像信息丢失问题,得到高精度的高光谱图像分类方法。

研究方法：

在Indian Pines和Pavia University数据集上,与4个已有的高光谱图像分类方法进行对比实验,比较OA, AA和Kappa值。

研究结果：

多尺度空洞卷积神经网络在Indian Pines和Pavia University数据集上OA值分别达到了99.58%,99.92%。AA值分别达到了99.57%,99.90%。Kappa分别达到了99.52%,99.89%。

结论：

1）在卷积神经网络中引入空洞卷积,可以有效避免图像信息丢失。

2）多尺度空洞卷积神经网络能提取更佳的判别性特征,实现高分类性能。

关键词：多尺度聚合;空洞卷积;高光谱图像分类;快捷连接

     

棒线材无头轧制系统工艺过程分析及控制系统研究

简要介绍了无头轧制的概念和无头轧制系统的研发概况,分析了棒线材无头轧制系统及其核心设备(移动式闪光焊机)的组成及功能特点,研究了棒线材无头轧制系统的工艺过程,列出了达涅利产品各组成装置的驱动方式、控制形式及作业特点.在此基础上,提出了基于PROFIBUS 总线和PLC控制器的系统控制方案,重点介绍了钢坯对接伺服控制策略以及焊机移动和钢坯位置随动传动系统的控制策略,并对两对接油缸、焊机与轧制钢坯、两焊机驱动电机的同步问题进行了分析.     

Jeffcott转子系统分岔点预测

首先简述了一种用于转子轴承系统的稳定性量化分析方法,即首先利用数值积分对高维非线性转子系统进行解耦,将Rn轨线映射为一系列R1映像轨线,然后在R1观察空间中定义轨线的稳定裕度,根据轨线稳定裕度利用灵敏度技术预测动力系统的分岔点。最后,对一个单跨转子模型试验台建立了动力学方程,并利用上述方法通过2个算例预测了系统发生分岔的参数值和分岔特性。预测结果与直接数值积分法在庞加莱截面得到的分岔参数值基本一致,但由于该方法利用了灵敏度技术,所以其分岔点的搜索过程比直接数值积分法中的试探法要快得多。     

基于分层建模技术的CAD/CAPP/CAM集成系统研究

在DM特征建模的基础上,建立了CAD、CAPP、CAM各个阶段的分层模型.分别从特征层和零件层两个层次建立该集成系统全局统一的数据表达.在工艺设计阶段通过引入特征子工艺设计概念与技术,完成子工艺的生成、拓扑排序、组合及编辑,从而完成整个零件的工艺规划.使得系统数据顺利地引入制造模块.该方法在所开发的回转类零件CAD/CAPP/CAM系统中得到了验证.     

基于粒子滤波算法的足底压力预测

针对人体下肢运动状态识别精度低的问题,提出了一种基于足底压力的下肢运动状态识别预测方法。以EMED足底压力平板采集的不同步速下各40组足底压力数据为试验样本,通过分析足底压力特征参数,构建步态相位,建立足底步态周期关系,以及步态位移模型。下肢运动是非线性运动,采用步态周期模型结合粒子滤波算法实现足底压力预测。先对粒子群初始化获取先验概率密度函数,对预测压力进行估计,其次对状态向量检验,使用多元线性回归推导出预测足底压力。实验结果表明,在不同步态速度下,粒子滤波算法性能好,精确度达到97%以上,从而证明了足底压力预测方法的有效性。补充不同年龄、性别、体重的实验者的足底压力数据进行分析,预测精度均在97.5%以上,验证了预测算法的稳定性和精准性。