A Control Lyapunov Function Approach to Stabilization of Affine Nonlinear Systems with Bounded Uncertain Parameters

This paper considers the robust stabilization problem of a class of affine nonlinear systems with bounded uncertain time-invariant parameters. A robust control Lyapunov function (RCLF) is introduced for the considered system. Based on the RCLF, a globally asymptotically stabilizing controller is then designed. The proposed controller is robust under the variant of system parameters. As the applications of the proposed scheme, the stabilization of uncertain feedback linearizable systems and the unified chaotic system are investigated, respectively. A numerical example on the unified chaotic system is also provided to illustrate the effectiveness of the presented method.     

木质素基高吸水性树脂的制备与溶胀行为

以木质素磺酸钠(LS-Na)、2-丙烯酰胺基-2-甲基丙磺酸(AMPS)、丙烯酸(AA)为原料,N,N-亚甲基双丙烯酰胺为交联剂,过硫酸钾为引发剂,采用微波辐射法,通过接枝共聚合成了具有生物降解性能的LS-g-PAMPS/AA高吸水性树脂。探讨了单体配比、LS-Na用量和单体总用量对LS-g-PAMPS/AA树脂吸水倍率的影响,研究了该树脂在各种盐溶液中的溶胀行为,并利用FTIR和TG等方法分析了该树脂的结构。实验结果表明,当m(AA)∶m(AMPS)=3、LS-Na用量(基于体系总质量,下同)为6%(w)和单体总用量为35%(w)时,LS-g-PAMPS/AA树脂在去离子水和生理盐水中的吸水倍率分别为1 217g/g和125 g/g。LS-g-PAMPS/AA树脂具有较强的热稳定性、耐盐性和盐响应性能,在不同的盐溶液里有良好的可逆行为和多次反复利用性能。     

百瓦级全光纤线偏振激光振荡器

报道了一种全光纤结构的高消光比(PER)线偏振激光振荡器。该光纤激光振荡器的谐振腔由一段双包层掺镱保偏光纤和一对与增益光纤匹配的光栅组成。弯曲损耗使快轴方向上的偏振模和高阶模受到抑制,实现了消光比优于15 d B的线偏振激光输出。最高输出功率为93.2 W,中心波长为1080 nm,光谱半峰全宽(FWHM)约为1.2 nm。增加抽运功率有望进一步提升功率。     

企业文化建设的探索与实践——以荆门石化为例

荆门石化重视企业文化建设,注重文化建设与企业经营管理深度融合,采取积极措施促进文化建设在职工群众中落地,取得了较好的效果。