关于高维矩阵运算及Fuzzy控制算法的探讨

本文讨论了高维(≥3维)矩阵的表示方法,定义了高维矩阵之间的某种运算,并通过几何的直观方法较系统的讨论了Fuzzy控制算法.     

分子动力学模拟不同入射能量的SiF2与SiC的相互作用

采用分子动力学模拟方法研究了入射能量对SiF2与SiC样品表面相互作用的影响。本次模拟选择的入射初始能量分别为0.3,1,5,10和25 eV。模拟结果显示SiF2分解率与Si和F原子的沉积率有密切的关系。沉积的Si和F原子在SiC表面形成一层SixFy薄膜。随入射能量的增加,薄膜厚度先增加后减小,薄膜中Si-Si键密度增大。构成薄膜的主要成分SiFx(x=1~4)中主要是SiF和SiF2,随入射能量的增加,薄膜成分由SiF2向SiF转变。     

Study of Welding Distortion and Residual Stress Considering Nonlinear Yield Stress Curves and Multi-constraint Equations

Journal of Materials Engineering and Performance - Inherent strain analysis has been successfully applied to predict welding deformations of large-scale structural components, while...     

Review on finite element analysis of welding deformation and residual stress

Welding deformation and residual stress have negative influence on assembly accuracy and service performance. Thermal elastic plastic (TEP) and inherent strain finite element analysis (FEA) methods were used to study this challenge. Basic principle of these two methods was first introduced. The influence of welding process, constraints, solid phase transformation and multi-pass welding on deformation and residual stress was discussed, and computation accuracy and efficiency were summarised. Loading method of inherent strain in inherent strain FEA was analysed, interface element was introduced to simulate effects of the gap on deformation in assembly welding especially for large structures. The future work, including accurately multiscale TEP model, efficiently transient prediction method of large structures, and flexible evaluation software, was planned.     

超精导辊成套轴承快速拆装拉马的设计

为了解决超精机导辊装卸时易出现轴承档变形和中心孔被破坏的问题,通过实践分析,设计成套轴承快速拆装拉马,详细介绍其结构和工作原理。指出:成套轴承快速拆装拉马在传统拉马的基础上增加铜哈弗、尼龙平顶尖和轴承装配隔套,并将拉马爪改制成拉马臂;不仅实现了超精导辊轴承的快速拆装,避免轴承在装卸过程中受到损伤,亦提高超精导辊装配精度和轴承使用寿命,省时降本。     

考虑谐振回路损耗的辅助谐振换流极开关损耗分析

为了精确分析辅助谐振换流极(ARCP)软开关技术对变流设备开关损耗的影响,本文在考虑了谐振回路杂散参数的基础上,对ARCP软开关技术换流过程进行详尽的分析,通过数学推导建立了更为准确的ARCP换流方程和开关损耗模型。最后通过实验验证了换流方程以及ARCP损耗模型的正确性。研究表明,尽管ARCP软开关技术能够基本消除功率器件的开关损耗,但是谐振回路带来了额外的损耗。因此ARCP软开关技术的理想模型不再适用,必须考虑各部分杂散参数对ARCP的影响,并在设计中尽量减小杂散参数,否则很难达到提高效率的目的。     

基于ARM单片机的无线行驶记录仪设计

随着车辆的普及,行驶记录仪在车辆中有广泛应用,介绍了一种基于无线通信的行驶记录仪,解决大型场站车辆读取行车数据的难题。首先介绍了无线行驶记录仪系统的组成,其次重点论述了无线行驶记录仪硬件接口和设计实现形式,并对记录仪软件架构以及控制流程、记录仪管理软件使用方法等内容做了介绍,最后对行驶记录仪使用情况和达到的效果进行了总结。用户反馈表明无线行驶记录仪状态稳定,读取数据方便,管理软件运行可靠,特别适用于大型场站车辆管理使用。     

蓄电池剩余容量预测技术现状及发展

阀控式密封铅酸(VRLA)蓄电池被广泛应用于邮电、电力、交通、军事等诸多领域,在整个系统中发挥着举足轻重的作用。因此,对蓄电池的运行状态,特别是剩余容量(荷电状态)进行在线准确监测(预测)以及有效的管理变得尤为重要。本文以VRLA蓄电池为对象,对国内外蓄电池剩余容量预测技术研究进行了详细的介绍和总结。     

Fault-tolerant shortest connection topology design for formation control

This paper studies the fault tolerant formation keeping problem of multi-agent systems with consideration of shortest connection topology. This is motivated by the requirement of low communication cost which largely depends on the communication length. Given a formation shape, a connection topology design method and its reconfiguration strategy are proposed in the sense that the whole connection path is shortest despite of communication faults. A control framework that combines the individual formation controller of each agent and connection topology is further presented. The stability of the whole system process is analyzed by switched system theories. Simulation results of unmanned aerial vehicles (UAVs) show the effectiveness of the proposed strategy.