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Saturated output feedback tracking control for robot manipulators via fuzzy self-tuning

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Journal of Zhejiang University-Science C(Computers and Electronics) 2010年第12期11卷 956-966页

作者： hua-shan liu Shi-qiang ZHU Zhang-wei CHE State Key Lab of Fluid Power Transmission and Control Zhejiang University Hangzhou 310027 China College of lnformation Science and Technology Donghua University Shanghai 201620 China

This paper concerns the problem of output feedback tracking (OFT) control with bounded torque inputs of robot manipulators, and proposes a novel saturated OFT controller based on fuzzy self-tuning proportional and derivative (PD) gains. First, aiming to accomplish the whole closed-loop control with only position measurements, a linear filter is involved to generate a pseudo velocity error signal. Second, different from previous strategies, the arctangent function with error-gain is applied to ensure the boundedness of the torque control input, and an explicit system stability proof is made by using the theory of singularly perturbed systems. Moreover, a fuzzy self-tuning PD regulator, which guarantees the continuous stability of the overall closed-loop system, is added to obtain an adaptive performance in tackling the disturbances during tracking control. Simulation showed that the proposed controller gains more satisfactory tracking results than the others, with a better dynamic response performance and stronger anti-disturbance capability.

关键词： Robot Tracking systems Bounded torque input Fuzzy control Output feedback

New Tripartite Nonlinear Entangled State Representation in Quantum Mechanics

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Communications in Theoretical Physics 2008年第10期50卷 867-872页

作者： KUANG Mai-hua MA shan-Jun liu Dong-Mei College of Physics ＆ Communication Electronics Jiangxi Normal University Nanchang 330022 China

Based on the technique of integral within an ordered product of nonlinear bosonic operators,we constructa new kind of tripartite nonlinear entangled state |α,γ〉_λ in 3-mode Fock space,which can make up a complete ... 详细信息

关键词： nonlinear 3-mode entangled state

柔性关节机器人有界自适应输出反馈控制（英文）

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2018年第7期19卷 557-578页

作者： hua-shan liu Yong huaNG College of Information Science and Technology Donghua University

目的:考虑关节驱动力矩受限、结构参数不确定以及缺少部分传感器测量等情况,本文研究力矩输入有界的一般柔性关节机器人自适应输出反馈控制方法,以提高轨迹跟踪性能。创新点:1.提出一种基于校正控制的强柔性关节机器人控制方法;2.设计... 详细信息

目的:考虑关节驱动力矩受限、结构参数不确定以及缺少部分传感器测量等情况,本文研究力矩输入有界的一般柔性关节机器人自适应输出反馈控制方法,以提高轨迹跟踪性能。创新点:1.提出一种基于校正控制的强柔性关节机器人控制方法;2.设计一类力矩控制输入有界的自适应输出反馈轨迹跟踪控制器。方法:1.引入校正控制,突破传统奇异摄动方法仅适用于弱柔性关节机器人的限制;2.通过一类光滑饱和函数和投影型自适应控制律,确保在参数不确定情况下力矩控制输入的有界性;3.利用近似微分滤波和高增益观测实现仅需电机侧和连杆侧位置测量的输出反馈控制。结论:1.提出的校正控制策略能够较好地适应不同程度的关节柔性;2.设计的有界自适应输出反馈控制方法可严格确保作业全程的控制输入值有界,且具有良好的轨迹跟踪性能。

关键词：机器人柔性关节输出反馈控制有界控制自适应控制

Evolution and Application of Sealing Ability of Gypsum Caprocks under Temperature-Pressure Coupling:An Example of the ZS5 Well in the Tazhong Area of the Tarim Basin

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Acta Geologica Sinica(English Edition) 2024年第1期98卷 168-184页

作者： liu hua ZHAO shan YANG Xianzhang ZHU Yongfeng WANG Shen ZHANG Ke National Key Laboratory of Deep Oil and Gas China University of Petroleum(East China)QingdaoShandong 266580China School of Geosciences China University of Petroleum(East China)QingdaoShandong 266580China Laboratory for Marine Mineral Resources National Laboratory for Marine Science and TechnologyQingdaoShandong 266071China PetroChina Tarim Oil Field Company KorlaXinjiang 841001China

Gypsum caprocks'sealing ability is affected by temperature-pressure *** to the limitations of experimental conditions,there is still a lack of triaxial stress-strain experiments that simultaneously consider changes in temperature and pressure conditions,which limits the accuracy of the comprehensive evaluation of the brittle plastic evolution and sealing ability of gypsum rocks using temperature pressure *** stress-strain tests were utilized to investigate the differences in the evolution of the confinement capacity of gypsum rocks under coupled temperaturepressure action and isothermal-variable pressure action on the basis of sample feasibility *** to research,the gypsum rock's peak and residual strengths decrease under simultaneous increases in temperature and pressure over isothermal pressurization experimental conditions,and it becomes more *** reduces the amount of time it takes for the rock to transition from brittle to *** temperature is taken into account,both the brittle–plastic transformation's depth limit and the lithological transformation of gypsum rocks become shallower,and the evolution of gypsum rocks under variable temperature and pressure conditions is more complicated than that under isothermal *** sealing ability under the temperature-pressure coupling is more in line with the actual geological context when the application results of the Well#ZS5 are *** provides a theoretical basis for precisely determining the process of hydrocarbon accumulation and explains why the early hydrocarbon were not well preserved.

关键词： temperature-pressure coupling gypsum caprocks brittle-plastic evolution sealing capacity Tarim Basin

Hourly land surface temperature retrieval over the Tibetan Plateau using Geo-LightGBM framework: Fusion of Himawari-8 satellite, ERA5 and site observations

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Advances in Climate Change Research 2024年第4期15卷 623-635页

作者： Zhao-hua liu shan-shan WENG Zhao-Liang ZENG Ming-Hu DING Ya-Qiang WANG Zhehao LIANG Civil and Surveying&Mapping Engineering Jiangxi University of Science and TechnologyGanzhou 341000China State Key Laboratory of Severe Weather Chinese Academy of Meteoroogical Sciences Beijing 100081China Space Geodesy and Geoinformation Technical Unviersity of BerlinBerlin 10623Germany

The Tibetan Plateau(TP)is highly sensitive to even minor fluctuations in land surface temperature(LST),which can result in permafrost melting and degradation of alpine grasslands,leading to serious ecological ***,it is crucial to have high-temporal-resolution and seamless hourly estimating and monitoring of LST for a better understanding of climate change on the ***,we employed Himawari-8 satellite,Digital Elevation Model(DEM),ERA5 reanalysis and meteorological station observations data to develop a new LightGBM framework(called Geo-LightGBM)for estimating LST on the TP,and then analyzed the spatiotemporal variations of those ***-LightGBM demonstrated excellent LST estimation accuracy,with an R2(coefficient of determination)of 0.971,RMSE(root-mean-square error)of 2.479℃,and MAE(mean absolute error)of 1.510℃.The estimated LST values for the year 2020 agreed well with observed values,with remarkable differences in hourly LST ***,the estimated LST was more accurate than that from ***,there were two high LST centers,located in the Yarlung Zangbo River Basin and the Qaidam Basin,and a low LST center located in the central *** SHAP(SHapley Additive exPlanations)and correlation analyses revealed DSCS(the mean ground downward shortwave radiation under clear-sky conditions)to be the most importantly input variable for estimating *** dummy variables(e.g.,longitude,latitude,DEM)were also found to be crucial for model accuracy *** findings indicate the potential for constructing a high-precision and seamless 24-h LST real-time retrieval and monitoring platform for the TP by combining satellite and China's independently developed CLDAS(China Land Data Assimilation System)data in future.

关键词： Tibetan Plateau Himawari-8 ERA5 Land surface temperature Geo-LightGBM

The RNA-binding domain of DCL3 is required for long-distance RNAi signaling

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aBIOTECH 2024年第1期5卷 17-28页

作者： Jie Li Bo-Sen Zhang hua-Wei Wu Cheng-Lan liu Hui-shan Guo Jian-hua Zhao State Key Laboratory of Plant Genomics Institute of MicrobiologyChinese Academy of SciencesBeijing 100101China CAS Center for Excellence in Biotic Interactions University of the Chinese Academy of SciencesBeijing 100049China Qilu Zhongke Academy of Modern Microbiology Technology Jinan 250022China

Small RNA(sRNA)-mediated RNA silencing(also known as RNA interference,or RNAi)is a conserved mechanism in eukaryotes that includes RNA degradation,DNA methylation,heterochromatin formation and protein translation *** plants,sRNAs can move either cell-to-cell or systemically,thereby acting as mobile silencing signals to trigger noncell autonomous ***,whether and what proteins are also involved in noncell autonomous silencing have not been *** this study,we utilized a previously reported inducible RNAi plant,PDSi,which can induce systemic silencing of the endogenous PDS gene,and we demonstrated that DCL3 is involved in systemic PDS silencing through its RNA binding *** confirmed that the C-terminus of DCL3,including the predicted RNA-binding domain,is capable of binding short *** affecting RNA binding,but not processing activity,reduced systemic PDS silencing,indicating that DCL3 binding to RNAs is required for the induction of systemic *** mosaic virus infection assays showed that the RNA-binding activity of DCL3 is required for antiviral RNAi in systemically noninoculated *** findings demonstrate that DCL3 acts as a signaling agent involved in noncell autonomous silencing and an antiviral effect in addition to its previously known function in the generation of 24-nucleotide sRNAs.

关键词： RNAi signaling DCL3 RBD RNAs Cucumber mosaic virus

Regioselective C-C bond cleavage/aminocarbonylation cascade under copper catalysis

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Science China Chemistry 2024年第11期67卷 3798-3806页

作者： Qi-Chao shan Yan Zhao Yong Wu Hong-Fei liu Xin-hua Duan Li-Na Guo Department of Chemistry School of Chemistry Energy Research Center of Energy Storage Materials and Devices Ministry of EducationXi'an Jiaotong University State Key Laboratory of Applied Organic Chemistry Lanzhou University

A regioselective C-C bond cleavage/aminocarbonylation cascade is presented. In recent years, tremendous progress has been made in the alkoxyl radical-mediated C-C bond cleavage of unstrained monocarbocycles. In contrast, the deconstruction and functionalization of bicyclic skeletons has been less developed and has mainly focused on the ring expansion process. Inspired by the aromatization-driven C-C bond cleavage, here we demonstrate a ring-opening/aminocarbonylation cascade under copper catalysis, in which the formation of a stable γ-lactam or succinimide skeleton reverses the selectivity of C-C cleavage. Remarkably, the photo and thermal assistance is not required when the succinimide skeleton is formed during the ring opening process. DFT calculations revealed that this unexpected ring-opening process is thermodynamically and kinetically favourable.

关键词： C-C bond cleavage controllable regioselectivity aminocarbonylation bicyclic alkoxy radical

Elevated preoperative CA125 is associated with poor survival in patients with metastatic colorectal cancer undergoing primary tumor resection:a retrospective cohort study

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Gastroenterology Report 2022年第1期10卷 386-394页

作者： Jun-hua huang hua-shan liu Tuo Hu Zong-Jin Zhang Xiao-Wen He Tai-Wei Mo Xiao-Feng Wen Ping Lan Lei Lian Xian-Rui Wu Department of Colorectal Surgery The Sixth Affiliated Hospital of Sun Yat-sen UniversityGuangzhouGuangdongP.R.China Guangdong Provincial Key Laboratory of Colorectal and Pelvic Floor Diseases The Sixth Affiliated Hospital of Sun Yat-sen UniversityGuangzhouGuangdongP.R.China Department of Gastric Surgery The Sixth Affiliated Hospital of Sun Yat-sen UniversityGuangzhouGuangdongP.R.China

Background The impact of the preoperative carbohydrate antigen 125(CA125)level on the survival of metastatic colorectal cancer(CRC)patients undergoing primary tumor resection(PTR)remains *** aim of this study was to assess the prognostic value in overall survival(OS)and cancer-specific survival(CSS)between patients with and without an elevated preoperative CA125 *** All metastatic CRC patients receiving PTR between 2007 and 2017 at the Sixth Affiliated Hospital of Sun Yat-sen University(Guangzhou,China)were retrospectively *** and CSS rates were compared between patients with and without elevated preoperative CA125 *** Among 326 patients examined,46(14.1%)exhibited elevated preoperative CA125 levels and the remaining 280(85.9%)had normal preoperative CA125 *** with elevated preoperative CA125 levels had lower body mass index,lower preoperative albumin level,lower proportion of preoperative chemotherapy,higher carcinoembryonic antigen and carbohydrate antigen 19–9(CA19–9)levels,poorer differentiation,and more malignant histopathological type than patients with normal preoperative CA125 *** addition,patients with elevated preoperative CA125 levels exhibited more advanced pathological T and N stages,more peritoneal metastasis,and more vessel invasion than patients with normal preoperative CA125 ***,the primary tumor was more likely to be located at the colon rather than at the rectum in patients with elevated CA125 *** OS and CSS rates in patients with elevated preoperative CA125 levels were significantly lower than those in patients with normal preoperative CA125 *** Cox regression analysis revealed that an elevated preoperative CA125 level was significantly associated with poor prognosis in metastatic CRC patients undergoing *** hazard ratio(HR)in OS was 2.36(95%confidence interval[CI],1.67–3.33,P<0.001)and the HR in CSS was 2.50(95%CI,1.77–3.55,P<0.001).The survival anal

关键词： metastatic colorectal cancer primary tumor resection CA125 prognosis survival

Field survey and analysis on near-fault severely damaged high-speed railway bridge in 2022 M6.9 Menyuan earthquake

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Earthquake Engineering and Engineering Vibration 2024年第4期23卷 1043-1055页

作者： Lin Xuchuan liu Fuxiang shan Wenchen Key Laboratory of Earthquake Engineering and Engineering Vibration Institute of Engineering MechanicsChina Earthquake AdministrationHarbin 150080China Key Laboratory of Earthquake Disaster Mitigation Ministry of Emergency ManagementHarbin 150080China Institute of Smart City and Intelligent Transportation Southwest Jiaotong UniversityChengdu610000China

The 2022 M6.9 Menyuan earthquake caused severe damage to a high-speed railway bridge,which was designed for high-speed trains running at speeds of above 250 km/h and is located right next to the *** of this type have been widely used for rapidly constructing the high-speed railway network,but few bridges have been tested by near-fault devastating *** potential severe impact of the earthquake on the high-speed railway is not only the safety of the infrastructure,trains and passengers,but also economic loss due to interrupted railway ***,a field survey was carried out immediately after the earthquake to collect time-sensitive *** damage to the bridge was carefully investigated,and quantitative analyses were conducted to better understand the mechanism of the bridge *** was found that seismic action perpendicular to the bridge’s longitudinal direction caused severe damage to the girders and rails,while none of the piers showed obvious deformation or *** maximum values of transverse displacement,out-of-plane rotation and twisting angle of girders reached 212.6 cm,3.1 degrees and 19.9 degrees,respectively,causing severe damage to the bearing supports and anti-seismic retaining *** observations provide a basis for improving the seismic design of high-speed railway bridges located in near-fault areas.

关键词： Menyuan earthquake field survey high-speed railway bridge near fault seismic damage