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Chinese Journal of Aeronautics 2021年第2期34卷 396-406页

作者： Yao lu Beijing Aerospace Automatic Control Institute Beijing 100854China National Key Laboratory of Science and Technology on Aerospace Intelligence Control Beijing 100854China

In this paper a nonlinear control method is proposed for the tracking control of hypersonic flight vehicles. The designed control laws do not utilize the measured flight path angle due to its inferior accuracy in practical engineering. For this, an estimated flight path angle is designed via the measurements of the altitude and velocity. A tracking differentiator is designed for constructing nonlinear disturbance observer which is used to estimate the model uncertainties including the parameter indeterminacies and external disturbances in the channels of velocity and pitch rate. A robust high-order differentiator is introduced to avoid the employment of the measured flight path angle and estimate the lumped disturbance in dynamics of flight path angle. Meanwhile, the possible saturation of the control inputs is considered and compensated by the auxiliary states. The boundness of closed-loop signals is proved through the Lyapunov theory. Comparative simulations are carried out and the results demonstrate the effectiveness of the proposed method.

关键词： Anti-saturation Backstepping Disturbance observer Flight control Hypersonic flight vehicle State estimation

山姜素调节cAMP/PKA/CREB信号通路促进骨质疏松性骨折大鼠骨折愈合

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中国组织工程研究 2025年第12期29卷 2438-2443页

作者：陆飞周静金涛连云港市第一人民医院康复医学科江苏省连云港市222000 南京医科大学康达学院康复医学部江苏省连云港市222000 中国人民解放军东部战区总医院健康医学科江苏省南京市210018

背景:山姜素具有抗炎、抗肿瘤、抗菌等作用,已被证实能够缓解骨质疏松症,但山姜素对骨质疏松性骨折的影响及机制仍不清楚。目的:探讨山姜素调节环磷酸腺苷/蛋白激酶A/环磷酸腺苷反应元件结合蛋白信号通路对骨质疏松性骨折大鼠的改善作... 详细信息

背景:山姜素具有抗炎、抗肿瘤、抗菌等作用,已被证实能够缓解骨质疏松症,但山姜素对骨质疏松性骨折的影响及机制仍不清楚。目的:探讨山姜素调节环磷酸腺苷/蛋白激酶A/环磷酸腺苷反应元件结合蛋白信号通路对骨质疏松性骨折大鼠的改善作用。方法:采用双侧卵巢切除手术构建骨质疏松症骨折大鼠模型,将成功造模大鼠依据随机数字表法分为山姜素低、中、高剂量组、抑制剂组和模型组,另选12只大鼠作为假手术组。骨折造模当天,山姜素低、中、高剂量组大鼠灌胃7.5,15,30 mg/kg的山姜素+腹腔注射等量的生理盐水,抑制剂组灌胃30 mg/kg的山姜素+腹腔注射5 mg/kg的H-89(通路抑制剂),模型组与假手术组给予(灌胃+腹腔注射)等量生理盐水,1次/d,连续8周。放射性检查评估大鼠骨折愈合情况并进行愈合评分;骨密度扫描仪测定骨折处骨密度;通过三点弯曲实验和压缩实验评估大鼠股骨生物力学状况;苏木精-伊红染色观察大鼠骨折处病理损伤;酶联免疫吸附(ELISA)法检测血清碱性磷酸酶、骨钙素和Ⅰ型胶原交联C-末端肽、环磷酸腺苷水平的变化;Western blot检测股骨组织中骨形态发生蛋白2和环磷酸腺苷/蛋白激酶A/环磷酸腺苷反应元件结合蛋白通路蛋白表达。结果与结论:①相较于假手术组,模型组大鼠骨折愈合评分、骨密度、最大负荷、最大应力、碱性磷酸酶、骨钙素、环磷酸腺苷水平、骨形态发生蛋白2、磷酸化蛋白激酶A/蛋白激酶A、磷酸化环磷酸腺苷反应元件结合蛋白/环磷酸腺苷反应元件结合蛋白表达下降,Ⅰ型胶原交联羧基末端肽水平增加(P<0.05);与模型组比较,山姜素各剂量组大鼠上述各项指标呈现相反的变化(P<0.05);与山姜素高剂量组比较,抑制剂组大鼠上述指标变化均被逆转(P<0.05)。②结论:山姜素可能通过激活环磷酸腺苷/蛋白激酶A/环磷酸腺苷反应元件结合蛋白信号通路加速骨质疏松症骨折大鼠的骨折愈合。

关键词：山姜素环磷酸腺苷/蛋白激酶A/环磷酸腺苷反应元件结合蛋白骨质疏松骨折愈合大鼠

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农业“水-能源-粮食”系统协同的生态效应

生态经济 2025年第1期41卷 149-157页

作者：卢召艳黎红梅湖南农业大学经济学院湖南长沙410128

厘清农业“水—能源—粮食”系统协同的生态效应对于促进农业绿色低碳发展具有重要意义。为此,基于中国2000—2021年的省际面板数据,采用双向固定效应模型考察农业“水—能源—粮食”系统协同对农业生态环境的影响,而后构建中介效应模... 详细信息

厘清农业“水—能源—粮食”系统协同的生态效应对于促进农业绿色低碳发展具有重要意义。为此,基于中国2000—2021年的省际面板数据,采用双向固定效应模型考察农业“水—能源—粮食”系统协同对农业生态环境的影响,而后构建中介效应模型和调节效应模型进一步明晰二者间的作用机制。研究结果显示:(1)农业“水—能源—粮食”系统协同能够显著提高农业生态环境质量,且经过一系列稳健性检验后结论依然成立。(2)异质性分析表明,农业“水—能源—粮食”系统协同的生态效应在粮食主产区和中西部地区更加显著。(3)作用机制检验发现,农业“水—能源—粮食”系统协同主要通过规模化经营和种植结构调整提高农业生态环境质量,环境规制在农业“水—能源—粮食”系统协同的生态效应中产生正向调节作用。基于此,需建立以水资源节约集约利用为核心的粮食高质量发展机制;重视规模化经营及种植结构调整在提高农业生态环境质量中发挥的重要作用;积极探索差异化的区域农业“水—能源—粮食”协同政策;不断完善农业环保政策。

关键词：农业“水—能源—粮食”系统协同生态效应

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论苏轼的纪行组诗

海南大学学报（人文社会科学版） 2025年第1期43卷 8-15页

作者：路成文宋定坤华中科技大学人文学院湖北武汉430074

苏轼纪行组诗一百零六组,在文本形态、内容表现与风格特征三方面有显著的个人特色。这些组诗以记录行旅之间的单个事件为主,除纪行外,频繁叙及游览和社交。在宋诗重说理的风尚影响下,苏轼往往在纪行组诗中抒发一己之情感、阐发深刻的人... 详细信息

苏轼纪行组诗一百零六组,在文本形态、内容表现与风格特征三方面有显著的个人特色。这些组诗以记录行旅之间的单个事件为主,除纪行外,频繁叙及游览和社交。在宋诗重说理的风尚影响下,苏轼往往在纪行组诗中抒发一己之情感、阐发深刻的人生哲理。此外,他的纪行组诗不仅能突破传统纪行组诗对于诗人个体的关注,还能做到“情”“景”“事”“理”四者兼备,为唐宋纪行组诗的创作开辟新途。

关键词：苏轼纪行组诗文本形态内容表现风格特征

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Development of Novel Hybrid Hand Formed by a Parallel Wrist and Three Soft-flexible Fingers

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Journal of Bionic Engineering 2022年第5期19卷 1349-1358页

作者： Yi lu Zefeng Chang Yang lu College of Mechanical Engineering Yanshan UniversityQinhuangdao 066004China Harbin Electric Corporation(Qinhuangdao)Heavy Equipment Company Limited Qinhuangdao 066004China

A prototype of a novel hybrid hand is developed by combing a parallel wrist with three flexible *** dynamics model is established,its grabbed forces are measured,and its grabbing performances are ***,Jacobian and Hessian matrices of the moving platform in the parallel wrist are derived,the kinematics formulas for solving the general velocity and the general acceleration of the moving platform are *** its dynamics model is established for solving the dynamic actuation forces,the dynamic constrained forces of the developed hybrid ***,its simulation mechanism is constructed in Matlab,and the theoretical solutions of the kinematics and the dynamics of the developed hybrid hand are verified to be correct using its simulation ***,when objects with different mass are grabbed by prototype of hybrid hand in different poses,the grabbed forces are measured,and the grabbing performances are discovered and analyzed to verify its merits.

关键词： Hybrid hand Flexible finger mechanism Dynamics Parallel wrist Grabbing performance

Life:Ordinary World-Speech by lu Yao at Northwest University in December 1991

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Frontiers of Literary Studies in China-Selected Publications from Chinese Universities 2022年第2期16卷 186-198页

作者： lu Yao JIAO Haimin(record) 不详 Documentary Department Shaanxi Media ConvergenceXi'an 710061China

ⅠI have not done much preparation for today,since it is the end of the year and I have my hands *** the past years,I have had several opportunities to express my opinions,and I do not really have any new ***,I look forward to taking some specific questions from you to exchange our ideas,so I hope this lecture will be rewarding for you.

关键词： really since Northwest

The Historical Fate of lu Xun in Today＇s China

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Frontiers of Literary Studies in China-Selected Publications from Chinese Universities 2013年第4期7卷 529-540页

作者： lu Xun His Legacy Institute of Chinese Studies Delhi lndia 15-18 November 2012

＂The historical fate of lu Xun in today＇s China＂ is an enormous topic, and a discussion of this question can also encompass important questions of Chinese society, thought, and culture. I have not performed special...

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Controlled wrinkling analysis of thin films on gradient substrates

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Applied Mathematics and Mechanics(English Edition) 2017年第5期38卷 617-624页

作者： Jianzhong ZHAO Xingming GUO lu lu Shanghai Institute of Applied Mathematics and Mechanics Shanghai Key Laboratory of Mechanics in Energy EngineeringShanghai UniversityShanghai 200072China

The paper investigates continuously changing wrinkle patterns of thin films bonded to a gradient substrate. Three types of gradient substrates including exponential, power-law, and symmetry models are considered. The Galerkin method is used to dis- cretize the governing equation of film bonded to gradient substrates. The wavelength and the normalized amplitude of the wrinkles for substrates of various material gradients are obtained. The numerical simulation based on the finite element method （FEM） is used to evolve the wrinkle patterns. The result agrees well with that of the analytical model. It is concluded that localization of wrinkle patterns strongly depends on the material gradient. The critical membrane force depends on both the minimum value of wrinkle stiffness and the gradient of wrinkle stiffness when the wrinkle stiffness is at its minimum. This work provides a better understanding for local wrinkle formation caused by gradient substrates.

关键词： thin film gradient substrate wrinkle material gradient Galerkin method

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异构无人系统协同控制研究进展

工程科学学报 2025年第1期47卷 66-78页

作者：郭兴李擎姚其家鲁小雅北京科技大学自动化学院北京100083 工业过程知识自动化教育部重点实验室北京100083

面对复杂化、多样化和立体化的任务需求,异构无人系统将空、地、海跨域优势互补,最大化提升系统各方面能力,为未来协同作战和智慧民生提供有力的技术保障.首先,梳理了国内外在跨域协同领域出台的推动性文件,介绍了异构无人系统在军用、... 详细信息

面对复杂化、多样化和立体化的任务需求,异构无人系统将空、地、海跨域优势互补,最大化提升系统各方面能力,为未来协同作战和智慧民生提供有力的技术保障.首先,梳理了国内外在跨域协同领域出台的推动性文件,介绍了异构无人系统在军用、科研院所和民用等三方面的实际应用.其次,针对异构无人系统关键技术之一的协同控制,分别阐述了异构无人系统协同控制在一致性、轨迹跟踪和编队‒合围等三方面的最新进展.此外,还特别讨论了在不同通信条件下协同控制所面临的挑战和解决方案.其中,由于一致性和轨迹跟踪存在上层控制理论性和下层控制可行性的区别,进一步从滑模控制、自适应控制、反步控制和自适应动态规划等四方面对轨迹跟踪研究展开阐述.然后,为了更好地促进异构无人系统协同控制在实际中的应用,通过总结前人相关工作,讨论了其在多约束控制与实时性、多任务切换控制和跨域通信下稳定性等三方面亟需解决的技术瓶颈.最后,综合异构无人系统协同控制研究现状和实际需求来看,指出了其在深度强化学习与分布式博弈、人机交互以及反群体智能等三方面的发展趋势.

关键词：异构无人系统协同控制跨域协同任务需求技术瓶颈

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Study of damage to a high concrete dam subjected to underwater shock waves

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Earthquake Engineering and Engineering Vibration 2014年第2期13卷 337-346页

作者： lu lu Li Xin Zhou Jing Faculty of Architecture and Civil Engineering Huaiyin Institute of Technology The State Key Laboratory of Coastal and Offshore Engineering Dalian University of Technology

To study the effect of a strong underwater shock wave on a concrete dam, this research aims to improve hammer impact methods in model tests. Six 1:200 scale models were designed and tested under distributed impact loads. A device was deployed for a direct measurement of the impact force at the upstream face of the dams. The model dam bases were anchored to prevent displacement. The experimental results indicate that the top part of the concrete dam is a weak zone, and the impact failure initiates with a fracture on the top of the dam. The peak value of impact stress increases when the second crack appears in the concrete dam from the upstream face to the downstream face. And, the level of the second crack in the dam body is lower as the peak value of impact stress increases. In this study, dynamic analysis was conducted by calculating the results to verify the effectiveness of a device to directly measure the impact force. This method may be used to approximately forecast the damage of concrete dam and may also be useful in other engineering applications.

关键词： underwater shock wave hammer impact impact force high concrete gravity dam forecast damage