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L^q Interior Estimates of the Gradient for Weak Solutions of Quasilinear Elliptic Equations

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Acta Mathematica Sinica,English Series 2007年第12期23卷 2225-2234页

作者： Feng Ping yao yong yong CAI LMAM School of Mathematical Sciences Peking University Bering 100871 P. R. China

The authors present a new proof of L^q interior estimates of the gradient for weak solutions of a quasilinear elliptic equation of p-Laplacian type.

关键词： L^q interior estimates weak solutions quasilinear elliptic maximal function

Reinforcement learning based adaptive control for uncertain mechanical systems with asymptotic tracking

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Defence Technology（防务技术） 2024年第4期34卷 19-28页

作者： Xiang-long Liang Zhi-kai yao yao-wen Ge Jian-yong yao School of Mechanical Engineering Nanjing University of Science and TechnologyNanjing210094China College of Automation&College of Artificial Intelligence Nanjing University of Post and TelecommunicationNanjing210023China

This paper mainly focuses on the development of a learning-based controller for a class of uncertain mechanical systems modeled by the Euler-Lagrange *** considered system can depict the behavior of a large class of engineering systems,such as vehicular systems,robot manipulators and *** these systems are often characterized by highly nonlinear characteristics,heavy modeling uncertainties and unknown perturbations,therefore,accurate-model-based nonlinear control approaches become *** by the challenge,a reinforcement learning(RL)adaptive control methodology based on the actor-critic framework is investigated to compensate the uncertain mechanical *** approximation inaccuracies caused by RL and the exogenous unknown disturbances are circumvented via a continuous robust integral of the sign of the error(RISE)control *** from a classical RISE control law,a tanh(·)function is utilized instead of a sign(·)function to acquire a more smooth control *** developed controller requires very little prior knowledge of the dynamic model,is robust to unknown dynamics and exogenous disturbances,and can achieve asymptotic output ***,co-simulations through ADAMS and MATLAB/Simulink on a three degrees-of-freedom(3-DOF)manipulator and experiments on a real-time electromechanical servo system are performed to verify the performance of the proposed approach.

关键词： Adaptive control Reinforcement learning Uncertain mechanical systems Asymptotic tracking

Projectively flat Asanov Finsler metric

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第6期8卷 963-968页

作者： HAN Jing-wei YU yao-yong Department of Mathematics Zhejiang University Hangzhou 310027 China School of Science Hangzhou Dianzi University Hangzhou 310028 China

In this work, we study the Asanov Finsler metric F=α（β^2/α^2＋gβ/α＋1）^1/2exp{（G/2）arctan[β/（hα）＋G/2]}, where α=（αijy^iy^i）^1/2 is a Riemannian metric and β=by^i is a 1-fom, g∈（-2,2）, h=（1-g^2/4）^1/2, G=g/h. We give the necessary and sufficient condition for Asanov metric to be locally projectively flat, i.e., α is projectively flat and ,Sis parallel with respect to α. Moreover, we proved that the Douglas tensor of Asanov Finsler metric vanishes if and only if β is parallel with respect to α.

关键词： Exponential Finsler metric Projectively flat (α β)-metrics Douglas tensor

A dynamic signal coordination control method for urban arterial roads and its application

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Frontiers of Information Technology & Electronic Engineering 2016年第9期17卷 907-918页

作者： Guo-jiang SHEN yong-yao YANG College of Computer Science and Technology Zhejiang University of Technology Zhejiang Zheda Supcon Information Technique Co. Ltd.

We propose a novel dynamic traffic signal coordination method that takes account of the special traffic flow characteristics of urban arterial roads. The core of this method includes a control area division module and a signal coordination control module. Firstly, we analyze and model the influences of segment distance, traffic flow density, and signal cycle time on the correlation degree between two neighboring intersections. Then, we propose a fuzzy computing method to estimate the correlation degree based on a hierarchical structure and a method to divide the control area of urban arterial roads into subareas based on correlation degrees. Subarea coordination control arithmetic is used to calculate the public cycle time of the control subarea, up-run offset and down-run offset of the section, and the split of each intersection. An application of the method in Shaoxing City, Zhejiang Province, China shows that the method can reduce the average travel time and the average stop rate effectively.

关键词： Urban arterial Control subarea Coordination control Correlation degree Fuzzy logic Intelligent transportation

Projectively flat exponential Finsler metric

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第6期7卷 1068-1076页

作者： YU yao-yong YOU Ying Department of Mathematics Zhejiang University Hangzhou 310028 China

In this paper, we study a class of Finsler metric in the form F=αexp(β/α)+εβ, where α is a Riemannian metric and β is a 1-form, ε is a constant. We call F exponential Finsler metric. We proved that exponential Finsler metric F is locally projectively flat if and only if α is projectively flat and β is parallel with respect to α. Moreover, we proved that the Douglas tensor of expo-nential Finsler metric F vanishes if and only if β is parallel with respect to α. And from this fact, we get that if exponential Finsler metric F is the Douglas metric, then F is not only a Berwald metric, but also a Landsberg metric.

关键词： Exponential Finsler metric Projectively flat (α β)-metric Douglas tensor

The Transmission of Huizhou Culture to Foreign Students in China-- Under the Context of Soft Power

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学术界 2017年第5期 296-304页

作者： yao yong Department of Foreign Languages and Culture Anhui University Hefei Anhui 230601

Culture is an important aspect of soft *** Culture is one of the best representations of traditional Chinese culture and has been attached great importance by scholars both at home and ***'s vitally important to spread Huizhou Cultural values around the world to improve China's soft *** students in China are potential advocators of Chinese *** cultural information they get will be transmitted to their own *** should take some strategies to promote Huizhou Culture among foreign students so that the charm of Huizhou Culture can be noticed and recognized by many more people.

关键词：软实力惠州培养在中国的外国学生学产

Negative effects of transthyretin in high myopic vitreous on diabetic retinopathy

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International Journal of Ophthalmology(English edition) 2017年第12期10卷 1864-1869页

作者： Jun Shao yong yao Departm ent of Ophthalmology W uxi People’s Hospital Aflicted to Nanjing Medical UniversityWuxi 214023Jiangsu ProvinceChina

AIM：To analyze the relationship between vitreous transthyretin（TTR） levels,high myopia and diabetic retinopathy（DR）.METHODS：We selected 6722 individuals from the southern Jiangsu Province for diabetes and ophthalmic *** TTR concentration in the vitreous of 50 patients with high myopia and diabetes,50 patients with only DR,and 20 healthy controls were determined by *** factors in Tie2 pathway in DR development including vascular endothecial growth factor（VEGF）,Tie2,Angpt1,Angpt2,vascular endothelial growth factor receptor（VEGFR） 1 and VEGFR2 were also detected by ***：The prevalence of DR in patients with diabetes and myopia [〈6.00 diopter（D）],diabetes and high myopia（〉6.00 D）,and diabetes without myopia were 11.1%,2.5%,and 60.0%,*** vitreous TTR concentration of patients with diabetes and high myopia was approximately 6.5-and 4.2-times higher than those of patients with DR and healthy controls,respectively（P〈0.05）.Following the vitreous TTR concentration,the levels of VEGF,Tie2,Angpt1,Angpt2,VEGFR1 and VEGFR2 in vitreous of diabetes and high myopia patients,DR patients and healthy controls were detected as dramatically ***：The results suggest that TTR can affect the vitreous contents of key factors in Tie2 pathway for neovascularization,and there should be a protective association between abundant TTR levels in the vitreous of highly myopic patients and a decreased risk of DR.

关键词： transthyretin diabetic retinopathy highmyopia protective

Repression of retinal microvascular endothelial cells by transthyretin under simulated diabetic retinopathy conditions

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International Journal of Ophthalmology(English edition) 2016年第6期9卷 809-815页

作者： Jun Shao yong yao Department of Ophthalmology Wuxi People's Hospital Affiliated to Nanjing Medical University

AIM： To investigate biological effects of transthyretin （TTR） on the development of neovascularization under simulated diabetic retinopathy （DR） condition associated with high glucose and hypoxia. METHODS： Human retinal microvascular endothelial cells （hRECs） were cultured in normal and simulated DR environments with high glucose and hypoxia. The normal serum glucose concentration is approximately 5.5 mmol/L; thus, hyperglycemia was simulated with 25 mmol/L glucose, while hypoxia was induced using 200 μmol/L CoCI. The influence of TTR on hRECs and human retinal pigment epithelial cells （hRPECs） was determined by incubating the cells with 4μmol/L TTR in normal and abnormal media. A co -culture system was then employed to evaluate the effects of hRPECs on hRECs. RESULTS： Decreased hRECs and hRPECs were observed under abnormal conditions, including high- glucose and hypoxic media. In addition, hRECs were significantly inhibited by 4 pmol/L exogenous TTR during hyperglycemic culture. During co-culture, hRPECs inhibited hRECs in both the normal and abnormal environments. CONCLUSION： hREC growth is inhibited by exogenous TTR under simulated DR environments with highglucose and hypoxic, particularly in the medium containing 25 mmol/L glucose, hRPECs, which manufacture TTR in the eye, also represses hRECs in the same environment. TTR is predicted to inhibit the proliferation of hRECs and neovascularization.

关键词： transthyretin diabetic retinal human retinalmicrovascular endothelial cells human retinal pigmentepithelial cells hyperglycemia hypoxia

Observer-Based Control for a Cable-Driven Aerial Manipulator under Lumped Disturbances

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Computer Modeling in Engineering & Sciences 2023年第5期135卷 1539-1558页

作者： Li Ding yong yao Rui Ma College of Mechanical Engineering Jiangsu University of TechnologyChangzhou213000China

With the increasing demand for interactive aerial operations,the application of aerial manipulators is becoming more ***,there are a few critical problems on how to improve the energetic efficiency and pose control of the aerialmanipulator forpractical *** this paper,a novel cable-drivenaerialmanipulatorused for remote water sampling is proposed and then its rigid-flexible coupling dynamics model is constructed which takes joint flexibility into *** achieve high precision joint position tracking under lumped disturbances,a newly controller,which consists of three parts:linear extended state observer,adaptive super-twisting strategy,and fractional-order nonsingular terminal sliding mode control,is *** linear extended state observer is adopted to approximate unmeasured states and unknown lumped disturbances and achieve model-free control *** adaptive super-twisting strategy and fractional-order nonsingular terminal sliding mode control are combined together to achieve good control performance and counteract chattering *** Lyapunovmethod is utilized to prove the overall stability and convergence of the ***,various visualization simulations and ground experiments are conducted,verifying the effectiveness of our strategy,and all outcomes demonstrate its superiorities over the existing control strategies.

关键词： Aerial manipulator cable-driven adaptive super-twisting linear extend state observer fractional-order nonsingular terminal sliding mode