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Defence Technology（防务技术） 2021年第3期17卷 874-883页

作者： rong-hua lei Li Chen School of Mechanical Engineering and Automation Fuzhou UniversityFuzhou350116China

The dynamic modeling, finite-time trajectory tracking control and vibration suppression of a flexible two-link space robot are studied. Firstly, the dynamic model of the system is established by combining Lagrange method with assumed mode method. In order to ensure that the base attitude and the joints of space robot can reach the desired positions within a limited time, a non-singular fast terminal sliding mode(NFTSM) controller is designed, which realizes the finite-time convergence of the trajectory tracking errors. Subsequently, for the sake of suppressing the vibrations of flexible links, a hybrid trajectory based on the concept of the virtual control force is developed, which can reflect the flexible modes and the trajectory tracking errors simultaneously. By modifying the original control scheme, a NFTSM hybrid controller is proposed. The hybrid control scheme can not only realized attitude stabilization and trajectory tracking of joints in finite time, but also provide a new method of vibration suppression. The simulation results verify the effectiveness of the designed hybrid control strategy.

关键词： Finite-time Terminal sliding mode Flexible links Vibration suppression Virtual control force

Adaptive fault-tolerant control based on boundary estimation for space robot under joint actuator faults and uncertain parameters

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Defence Technology（防务技术） 2019年第6期15卷 964-971页

作者： rong-hua lei Li Chen School of Mechanical Engineering and Automation Fuzhou University

Since the joint actuator of the space robot executes the control instructions frequently in the harsh space environment,it is prone to the partial loss of control effectiveness(PLCE)*** adaptive fault-tolerant control algorithm is designed for a space robot system with the uncertain parameters and the PLCE actuator *** mathematical model of the system is established based on the Lagrange method,and the PLCE actuator fault is described as an effectiveness *** lower bound of the effectiveness factors and the upper bound of the uncertain parameters are estimated by an adaptive strategy,and the estimated value is fed back to the control *** with the traditional fault-tolerant algorithms,the proposed algorithm does not need to predetermine the lower bound of the effectiveness factor,hence it is more in line with the actual engineering *** is proved that the algorithm can guarantee the stability of the closed-loop system based on the Lyapunov function *** numerical simulation results show that the proposed algorithm can not only compensate for the uncertain parameters,but also can tolerate the PLCE actuator faults effectively,which verifies the effectiveness and superiority of the control scheme.

关键词： Space robot Actuator faults Uncertain parameters Effectiveness factor Fault-tolerant control

Global trend of review articles focused on cardiopulmonary bypass:Perspectives from bibliometrics

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World Journal of Methodology 2025年第2期15卷 166-173页

作者： lei Deng Rui Zhou Xian-Jie Zhang Yan-hua Peng Department of Gastroenterology Deyang People’s HospitalDeyang 618000Sichuan ProvinceChina Department of Anesthesiology and Perioperative Medicine Shanghai Fourth People's HospitalSchool of MedicineTongji UniversityShanghai 200434China Department of Anesthesiology Deyang People’s HospitalDeyang 618000Sichuan ProvinceChina

BACKGROUND Cardiopulmonary bypass(CPB)is a life-support technology widely used in *** articles reflect research advances in a certain topic or field within a certain period of *** To perform a bibliometric analysis of the review articles that focused on CPB for cardiovascular *** This study was based on a bibliometric *** were acquired from the Web of Science and basic bibliometric parameters were analyzed and visualized using VOSviewer and *** We identified 141 review articles on ***,the number of publications increased,and most of them were published in the 2010s(n=57,40.4%)and the 2020s(n=45,31.9%).There were 113(80.1%)narrative review articles,21(14.9%)meta-analysis studies and 7(5.0%)systematic review *** United States(n=25,17.7%)and China(n=21,14.9%)were the leading countries in terms of publication *** articles were published in 98 different *** Journal of Cardiothoracic and Vascular Anesthesia(n=14,10.0%)and Perfusion-United Kingdom(n=11,7.8%)were preferred by the *** high-frequency keywords included inflammatory response,children,acute kidney injury,meta-analysis and off-pump,except for CPB and cardiac *** response had the closest relationship with CPB during cardiac *** complications of CPB,including inflammatory response,kidney injury and ischemia,caught lots of *** The rapid increase of review papers shows that the research on CPB in cardiac surgery is increasingly being emphasized by scholars and clinical staff ***-analysis has been widely conducted to analyze clinical controversies and further guide clinical *** to improving the outcomes of patients undergoing cardiac surgery with CPB are the hot spots in this field.

关键词： Cardiopulmonary bypass Review article Bibliometric analysis Cardiac surgery Hot spots

Optimal investment based on relative performance and weighted utility

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Applied Mathematics(A Journal of Chinese Universities) 2024年第2期39卷 328-342页

作者： WANG lei DONG Ying-hui hua Chun-rong Department of Mathematics Suzhou University of Science and TechnologySuzhou 215009China Changshu Institute of Technology Changshu 215500China

This paper studies the optimal portfolio allocation of a fund manager when he bases decisions on both the absolute level of terminal relative performance and the change value of terminal relative performance comparison to a predefined reference point. We find the optimal investment strategy by maximizing a weighted average utility of a concave utility and an Sshaped utility via a concavification technique and the martingale method. Numerical results are carried out to show the impact of the extent to which the manager pays attention to the change of relative performance related to the reference point on the optimal terminal relative performance.

关键词： relative performance weighted utility S-shaped utility concavification

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全双工网络的友好干扰协作机制和功率分配

金陵科技学院学报 2018年第2期34卷 15-18页

作者：罗荣华雷俊胡国兵金陵科技学院网络与通信工程学院江苏南京211169 南京熊猫汉达科技有限公司江苏南京210094 金陵科技学院电子与信息工程学院江苏南京211169

在无线全双工中继网络中,假设中继节点是不可信任的,为了改善合法用户的物理层安全性能,利用友好干扰节点向中继节点发射干扰信号进行协作,且为了获得帮助,合法用户需向干扰节点支付一定的费用。基于此协作干扰机制,讨论了如何对友好干... 详细信息

在无线全双工中继网络中,假设中继节点是不可信任的,为了改善合法用户的物理层安全性能,利用友好干扰节点向中继节点发射干扰信号进行协作,且为了获得帮助,合法用户需向干扰节点支付一定的费用。基于此协作干扰机制,讨论了如何对友好干扰节点进行有效的功率分配,从而使得合法用户获得的效用达到最优。理论分析和仿真结果表明,由于中继节点采用了全双工技术,且利用友好干扰节点进行协作,并在此基础上进行最优功率分配,合法用户的物理层安全性能可得到有效提高。

关键词：全双工物理层安全友好干扰节点协作干扰机制功率分配

An Algorithmic Approach to the q-Summability Problem of Bivariate Rational Functions

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Journal of Systems Science & Complexity 2021年第1期34卷 107-121页

作者： WANG rong-hua School of Mathematical Sciences Tiangong UniversityTianjin 300387China

In 2014, Chen and Singer solved the summability problem of bivariate rational *** an algorithmic proof was presented by Hou and the author. In this paper, the algorithm will be simplified and adapted to the q-case.

关键词： Gosper's algorithm polynomial residues q-summability

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水稻不育系谷丰A的遗传提纯与原种繁殖技术

福建稻麦科技 2017年第3期35卷 9-12页

作者：蔡巨广李昭明胡荣华雷上平张以华福建省农业科学院水稻研究所福建福州350018 福建省将乐县农业科学研究所福建将乐353300

谷丰A是福建省农业科学院水稻研究所用"龙特浦B/宙伊B"杂交选育的保持系,再与地谷A测交、回交育成的籼型三系不育系,于2001年通过福建省科技成果鉴定。阐述了三系不育系谷丰A的主要特征特性,对谷丰A进行遗传提纯的关键技术及原种繁殖技术。

关键词：杂交水稻不育系谷丰A 遗传提纯原种繁殖

The impact of the digital economy on the servitization of industrial structures: the moderating effect of human capital

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Data Science and Management 2023年第3期6卷 174-182页

作者： rong Ran Xinyuan Wang Ting Wang lei hua School of Public Policy and Administration Chongqing UniversityChongqing400044China

The digital economy,which was born during the late third technological revolution,has caused significant economic and societal *** sluggish global economic growth,China’s economy is facing upgrades and *** sample selection for this study was conducted from 2013 to *** related to the digital economy and servitization of the industrial structure of 30 Chinese provinces,municipalities,and autonomous regions were *** study presents the human capital variable,based on which an econometric analysis was conducted,and examines its moderating *** findings indicate that even after the replacement variable indicator’s robustness test,the relationship between the digital economy and the servitization of industrial structures remains *** study demonstrats that the quality of human capital plays a positive role in this ***,a heterogeneity test demonstrated that there are different pathways for the impact of the digital economy on the servitization of industrial structures in the eastern,central,and western *** study provides evidence to help researchers understand the moderating utility of human capital.

关键词： Digital economy Human capital Industrial structure servitization Moderating effect model

Synthesis and formation mechanism of nanocrystalline ZrB_(2)-Al_(2)O_(3)composite powders via an amorphous precursor

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Rare Metals 2021年第7期40卷 1801-1807页

作者： Shao-lei Song Yong-Li Fan rong Li Yue-hua Lin Qiang Zhen School of Materials Science and Engineering Shanghai UniversityShanghai 200072China Nano-Science and Technology Research Center Shanghai UniversityShanghai 200444China

ZrB_(2)-Al_(2)O_(3)composite powders were synthesized at 1100℃using a novel ZrB_(2)precursor and Al powders as raw *** final ZrB_(2)-Al_(2)O_(3)composite powders consisted of submicron Al_(2)O_(3)and nanosize ZrB_(2)(50-100 nm)particles,which were homogeneously mixed in *** with thermodynamic calculation and experiment results,the formation mechanism of ZrB_(2)-Al_(2)O_(3)composite powders was proposed as follows:ZrB_(2)precursor first decomposed into ZrO_(2)and *** reduction of ZrO_(2) and B_(2)O_(3) generated Zr and B atoms and the coproducts Al_(2)O_(3),and then,a series of reactions between Zr atoms,B atoms and Al took place to form ZrB_(2)and Al_(3)***,ZrB_(2),Al_(2)O_(3)and Al were obtained through a liquid-solid reaction between Al_(3)Zr andB2O3,which is the limiting step in the conversion *** the Al_(3)Zr was exhausted,the reaction between Al,ZrO_(2)and B became the main reaction to obtain ZrB_(2)and Al_(2)O_(3).

关键词： ZrB_(2)-Al_(2)O_(3)composite powders Sol-gel Formation mechanism Intermediate product Al_(3)Zr

基于弹丸膛内运动参数和压力测试的火炮膛内燃气温度估算方法

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火工品 2025年第1期 51-54页

作者：赵煜华闫光虎肖霞严文荣梁磊西安近代化学研究所陕西西安710065

为了解决火炮膛内测试环境恶劣而导致发射药燃气温度测试难度大的问题,基于微波干涉仪、压力测试系统,结合发射药配方性能计算理论、装药内弹道性能计算模型等理论,建立了一种基于实测参数的火炮膛内燃气温度估算方法,并开展了试验研究... 详细信息

为了解决火炮膛内测试环境恶劣而导致发射药燃气温度测试难度大的问题,基于微波干涉仪、压力测试系统,结合发射药配方性能计算理论、装药内弹道性能计算模型等理论,建立了一种基于实测参数的火炮膛内燃气温度估算方法,并开展了试验研究。结果表明:火炮膛内燃气温度的最高值约为2631.8 K,随着弹丸运动迅速降低,弹丸出炮口时膛内燃气温度降低到约1858.4 K;建立的火炮膛内发射药燃气温度估算方法可以有效地获得火炮整个内弹道过程中火药燃气温度随时间的变化规律,为低烧蚀发射药及装药的研制提供了一种新的研究手段。

关键词：发射药膛内燃气温度估算方法微波干涉仪

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