在整体式车辆稳定性轨迹跟踪控制架构的基础之上,设计了一种引入预瞄曲率信息的自适应预测时域非线性模型预测控制(NMPC).基于预瞄的参考路径曲率点列指导控制维度变化,提升控制器对于路径曲率的动态响应能力;进一步地,引入状态协调优...在整体式车辆稳定性轨迹跟踪控制架构的基础之上,设计了一种引入预瞄曲率信息的自适应预测时域非线性模型预测控制(NMPC).基于预瞄的参考路径曲率点列指导控制维度变化,提升控制器对于路径曲率的动态响应能力;进一步地,引入状态协调优化机制,使控制器显示耦合至上一控制周期的车辆状态空间,有效避免预测时域变化造成的多步优化问题解耦效应,抑制因控制输入突变对轨迹跟踪控制任务的影响.结合两种优化方法,有效改善固定预测时域策略在高曲率轨迹跟踪中因累计误差造成的跟踪精度下降问题.最后,基于MATLAB/Simulink-CarSim联合仿真平台对算法进行了验证.经计算,高速单移线工况下,该方法在侧向偏差均值/峰值、纵向偏差均值/峰值、航向偏差均值/峰值指标中,相较于固定预测时域NMPC同比降低36.17%/15.25%、11.55%/38.58%、6.13%/25.27%;高速双移线工况下,同比降低30.28%/29.77%、25.07%/3.85%、11.02%/2.68%.此外,在高速低附着工况中,该方法仍能保证良好的控制精度及侧向稳定性,其峰值侧向偏差为0.2017 m、峰值纵向偏差为0.9744 km h^(-1)、峰值航向偏差为1.1936°、峰值质心侧偏角为1.9074°.展开更多
目前已有一些针对路径跟踪控制中信号时滞问题的研究工作,但这些工作大多针对某种特定的控制方法,而在路径跟踪控制方法中,非线性模型预测控制(Nonlinear model predictive control,NMPC)具有能够显式处理系统约束、便于实现多目标优化...目前已有一些针对路径跟踪控制中信号时滞问题的研究工作,但这些工作大多针对某种特定的控制方法,而在路径跟踪控制方法中,非线性模型预测控制(Nonlinear model predictive control,NMPC)具有能够显式处理系统约束、便于实现多目标优化、能够有效利用被控对象前方参考路径信息等优势,但是针对NMPC路径跟踪控制系统中时滞问题的研究较不成熟,制约了这种控制方法的实际应用.为解决上述问题,开展了以下研究工作.首先构建了能够较好地孤立出时滞影响的类车机器人路径跟踪控制系统.接着分析了信号时滞对NMPC路径跟踪控制系统的影响机理,即时滞会导致控制器产生的控制信号不能适应类车机器人在执行控制信号时所处的位置.然后提出了基于增长NMPC预测时域的时滞影响消减方法,即在迭代周期不变的情况下,在无时滞系统较优预测步数的基础上增加二倍时滞周期比以上的整数.最后通过计算机仿真和实验验证了提出方法的有效性.仿真和实验结果表明,信号时滞对NMPC路径跟踪控制系统存在影响,未考虑时滞的NMPC控制算法能够在无时滞系统中实现高精确性路径跟踪,而在有时滞系统中控制失效.通过增长预测时域可以有效消减信号时滞的影响,在信号时滞约为0.2 s的仿真与实验系统中,基于该方法的NMPC控制器可以保证路径跟踪控制的位移误差幅值不超过0.1258 m,航向误差幅值不超过0.0583 rad.展开更多
Despite the synergy of immune checkpoint blockade(ICB) therapy and photodynamic therapy(PDT) holds great promise as countermeasures against breast cancer, exploring long-term or flexible short-time therapeutic strateg...Despite the synergy of immune checkpoint blockade(ICB) therapy and photodynamic therapy(PDT) holds great promise as countermeasures against breast cancer, exploring long-term or flexible short-time therapeutic strategies in “cold” tumors remains a great challenge. Here, we present a polyunsaturated fatty acid-doped liposomal hydrogel Lp(DHA)@CP Gel loaded with photosensitizer chlorin e6(Ce6) and programmed death-ligand 1 antibody(αPD-L1) for flexible local photoimmunotherapy with merely singledosed administration. The presence of polyunsaturated fatty acid(docosahexaenoic acid, DHA) doped in particle membrane endows liposomes with flexibly reactive oxygen species(ROS)-responsive release capability, which was attributed to the presence of abundant unsaturated groups. The αPD-L1 was repeatedly induced to in situ release in response to the PDT under photo-exposure. The immunogenic cell death(ICD) effect of PDT evoked “cold” breast tumor to “hot” one, and then assisted the cascade releasedαPD-L1 to synergistically boost the immunotherapy. After a single dose of peritumoral administration of Lp(DHA)@CP Gel, the on-demand treatment can maximize patient compliance and safety by adjusting therapeutic behaviors via a photo on-off switch. This work presents a flexible medication platform,showing promise in improving the objective response rate of ICB therapy and minimizing its systemic toxicity.展开更多
有柄石韦(Pyrrosia petiolosa)是水龙骨科石韦属植物,也是一种常用的中药材,被广泛用于治疗肾盂肾炎、慢性支气管炎、尿路结石等病症。通过检索中国知网、PubMed、Web of Science等数据库,查找国内外已经发表的有柄石韦相关文献,对有柄...有柄石韦(Pyrrosia petiolosa)是水龙骨科石韦属植物,也是一种常用的中药材,被广泛用于治疗肾盂肾炎、慢性支气管炎、尿路结石等病症。通过检索中国知网、PubMed、Web of Science等数据库,查找国内外已经发表的有柄石韦相关文献,对有柄石韦近四十年的化学成分和生物活性研究进行系统地梳理、归纳,发现目前已从有柄石韦中分离出超过100种化合物,包括黄酮类、三萜类、木脂素类、酚类和其他类等。有柄石韦提取物具有显著的生物活性,包括抗氧化、抗菌、抗炎、利尿、促进伤口愈合、抗肾结石、抗糖尿病等。可为有柄石韦药用资源后续深入系统地研究和临床开发提供科学依据和理论参考。展开更多
文摘在整体式车辆稳定性轨迹跟踪控制架构的基础之上,设计了一种引入预瞄曲率信息的自适应预测时域非线性模型预测控制(NMPC).基于预瞄的参考路径曲率点列指导控制维度变化,提升控制器对于路径曲率的动态响应能力;进一步地,引入状态协调优化机制,使控制器显示耦合至上一控制周期的车辆状态空间,有效避免预测时域变化造成的多步优化问题解耦效应,抑制因控制输入突变对轨迹跟踪控制任务的影响.结合两种优化方法,有效改善固定预测时域策略在高曲率轨迹跟踪中因累计误差造成的跟踪精度下降问题.最后,基于MATLAB/Simulink-CarSim联合仿真平台对算法进行了验证.经计算,高速单移线工况下,该方法在侧向偏差均值/峰值、纵向偏差均值/峰值、航向偏差均值/峰值指标中,相较于固定预测时域NMPC同比降低36.17%/15.25%、11.55%/38.58%、6.13%/25.27%;高速双移线工况下,同比降低30.28%/29.77%、25.07%/3.85%、11.02%/2.68%.此外,在高速低附着工况中,该方法仍能保证良好的控制精度及侧向稳定性,其峰值侧向偏差为0.2017 m、峰值纵向偏差为0.9744 km h^(-1)、峰值航向偏差为1.1936°、峰值质心侧偏角为1.9074°.
基金supported by the Natural Science Foundation of Guangdong Province (No.2023A1515030291)Science and Technology Program of Guangzhou (No.202201011130280065)+1 种基金National Natural Science Foundation of China (No.82172079)Special Fund of Foshan Climbing Peak Plan (No.2020B018)。
文摘Despite the synergy of immune checkpoint blockade(ICB) therapy and photodynamic therapy(PDT) holds great promise as countermeasures against breast cancer, exploring long-term or flexible short-time therapeutic strategies in “cold” tumors remains a great challenge. Here, we present a polyunsaturated fatty acid-doped liposomal hydrogel Lp(DHA)@CP Gel loaded with photosensitizer chlorin e6(Ce6) and programmed death-ligand 1 antibody(αPD-L1) for flexible local photoimmunotherapy with merely singledosed administration. The presence of polyunsaturated fatty acid(docosahexaenoic acid, DHA) doped in particle membrane endows liposomes with flexibly reactive oxygen species(ROS)-responsive release capability, which was attributed to the presence of abundant unsaturated groups. The αPD-L1 was repeatedly induced to in situ release in response to the PDT under photo-exposure. The immunogenic cell death(ICD) effect of PDT evoked “cold” breast tumor to “hot” one, and then assisted the cascade releasedαPD-L1 to synergistically boost the immunotherapy. After a single dose of peritumoral administration of Lp(DHA)@CP Gel, the on-demand treatment can maximize patient compliance and safety by adjusting therapeutic behaviors via a photo on-off switch. This work presents a flexible medication platform,showing promise in improving the objective response rate of ICB therapy and minimizing its systemic toxicity.
文摘有柄石韦(Pyrrosia petiolosa)是水龙骨科石韦属植物,也是一种常用的中药材,被广泛用于治疗肾盂肾炎、慢性支气管炎、尿路结石等病症。通过检索中国知网、PubMed、Web of Science等数据库,查找国内外已经发表的有柄石韦相关文献,对有柄石韦近四十年的化学成分和生物活性研究进行系统地梳理、归纳,发现目前已从有柄石韦中分离出超过100种化合物,包括黄酮类、三萜类、木脂素类、酚类和其他类等。有柄石韦提取物具有显著的生物活性,包括抗氧化、抗菌、抗炎、利尿、促进伤口愈合、抗肾结石、抗糖尿病等。可为有柄石韦药用资源后续深入系统地研究和临床开发提供科学依据和理论参考。
