Backstepping-based distributed coordinated tracking formultiple uncertain Euler-Lagrange systems

Based on the idea of backstepping design, distributedcoordinated tracking problems under directed topology are discussedfor multiple Euler-Lagrange （EL） systems. The dynamicleader case is considered. First, with the parameter-linearity property,a distributed coordinated adaptive control scheme is proposedfor EL systems in the presence of parametric uncertainties.Then, subject to nonlinear uncertainties and external disturbances,an improved adaptive control algorithm is developed by usingneural-network （NN） approximation of nonlinear functions. Bothproposed algorithms can make tracking errors for each followerultimately bounded. The closed-loop systems are investigated byusing the combination of graph theory, Lyapunov theory, and BarbalatLemma. Numerical examples and comparisons with othermethods are provided to show the effectiveness of the proposedcontrol strategies.

基于3D有限元分析方法的连铸坯传热及矫直的研究

弯板的矫直处理会产生较大的矫直应变。在多点矫直时,在每个矫直点都会出现矫直应变率峰值,如果应变率过大,则会出现矫直裂纹。本文分析了板坯的凝固过程和热传递,并通过三维有限元分析法(FEM)计算了坯壳的形成及其三维温度场。基于对弯板五点矫直的有限元分析,得到了每个矫直点的应变与应变率,为矫直裂纹的分析奠定了基础。

医护一体化临床路径在老年腹股沟疝患者围手术期应用

目的总结医护一体化临床路径在老年腹股沟疝患者围手术期的应用效果。方法对2021年6月至2022年6月,北京市垂杨柳医院普通外科96例老年腹股沟疝手术患者资料进行回顾性分析。依手术方式分为腹腔镜组与开放组,围手术期行医护一体化临床路径诊疗护理,观察并总结术后并发症、疼痛评分、排气时间、住院时间及患者满意度、知晓率、复查率情况。结果全部患者均顺利完成手术,痊愈出院。2组患者性别、术后并发症发生率差异无统计学意义。腹腔镜组年龄、术后疼痛评分低于开放组,术后肛门排气时间及住院日,高于开放组。2组满意度均达到100%,知晓率、复发率无统计学差异。结论患者对医护一体化临床路径认可度高、满意度高,能够节约医疗资源、促进康复进程、保障护理质量。