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Adaptive RISE Control of Winding Tension with Active disturbance Rejection

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Chinese Journal of Mechanical Engineering 2024年第4期37卷 135-145页

作者： Junjie mi Jianyong Yao Wenxiang deng School of Mechanical Engineering Nanjing University of Science and TechnologyNanjing 210094China

A winding system is a time-varying system that considers complex nonlinear characteristics,and how to control the stability of the winding tension during the winding process is the primary problem that has hindered development in this field in recent *** nonlinear factors affect the tension in the winding process,such as friction,structured uncertainties,unstructured uncertainties,and external *** terms severely restrict the tension tracking *** tension control strategies are mainly based on the composite control of the tension and speed loops,and previous studies involve complex decoupling *** to the large number of calculations required for this method,it is inconvenient for practical engineering *** simplify the tension generation mechanism and the influence of the nonlinear characteristics of the winding system,a simpler nonlinear dynamic model of the winding tension was *** adaptive method was applied to update the feedback gain of the continuous robust integral of the sign of the error(RISE).Furthermore,an extended state observer was used to estimate modeling errors and external *** model disturbance term can be compensated for in the designed RISE *** asymptotic stability of the system was proven according to the Lyapunov stability ***,a comparative analysis of the proposed nonlinear controller and several other controllers was *** results indicated that the control of the winding tension was significantly enhanced.

关键词： Winding tension Continuous robust integral of the sign of the error(RISE)control Adaptive control disturbance compensation Extended state observer(ESO) Tension control

Multidimensional coupled structure-activity relationship models for replacement of SF_(6)

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High Voltage 2024年第2期9卷 484-494页

作者： mi Zhang Hua Hou Baoshan Wang College of Chemistry and Molecular Sciences Wuhan UniversityWuhanChina

Computational screening of single gases to replace SF_(6)for electrical insulation has been challenged by the difficulty in combining various mutually exclusive properties especially for dielectric performance with liquefaction and environmental *** reveal the inherent correlations between dielectric strength(Er),boiling point(Tb),and global warming potential(GWP)of dielectric materials,a coupled structure-activity relationship(CSAR)model has been proposed for the first *** means of the generic descriptors,as deduced from the electrostatic potentials,and the specific descriptors,as introduced from the respective microscopic mechanisms,the complex interdependence between Er,Tb,and GWP of the insulation gases is quantitatively characterised by the 3-d coupling *** coupling mechanism for the right balance of properties is uncovered in terms of the first-principle *** CSAR model outperforms the previous SAR models in predicting Er,Tb,and GWP simultaneously in a self-consistent *** importantly,the concept of CSAR could be extended readily to any multidimensional macroscopic *** replacement compounds have been identified tentatively to be the promising candidates to replace SF_(6)using the CSAR model.

关键词： properties. dielectric insulation

The carbon border adjustment mechanism is inefficient in addressing carbon leakage and results in unfair welfare losses

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Fundamental Research 2024年第3期4卷 660-670页

作者： Xinlu Sun Zhifu mi Lu Cheng d'Maris Coffman Yu Liu The Bartlett School of Sustainable Construction University College LondonLondon WC1E 7HBUnited Kingdom College of Urban and Environmental Sciences Peking UniversityBeijing 100871China

The European Commission has proposed a Carbon Border Adjustment Mechanism(CBAM)to reduce carbon leakage and create a level playing field for its domestic products and imported ***,the effectiveness of the proposal remains unclear,especially when it triggers threats of retaliation from trading partners of the European *** apply a Computable General Equilibrium model-Global Trade Analysis Project-to assess the economic and environmental impacts of different CBAM *** we show that the effectiveness of the CBAM to address carbon leakage risks is rather limited,and the CBAM raises concerns over global welfare costs,Correct to Gross domestic Product(GdP)losses,and violation of equality *** retaliation leads to multiplied welfare losses,which would mostly be borne by poor *** results question the carbon leakage reduction effect of a unilateral trade policy and suggest that climate change mitigation still needs to be performed within the framework of international cooperation.

关键词： Carbon border adjustment mechanism Carbon leakage Climate change mitigation Floorcarbon price Trade retaliation

distributed Region Tracking and Perimeter Surveillance for Second-Order Multi-Agent Systems in Star-Shaped Sets

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Journal of Systems Science & Complexity 2024年第5期37卷 1995-2020页

作者： SHANG Juan MO Lipo mi Rongxin CAO Xianbing School of Mathematics and Statistics Beijing Technology and Business UniversityBeijing 100048China The department of Foundation Shijiazhuang Institute of Railway TechnologyShijiazhuang 050041China School of Computer and Artificial Intelligence Beijing Technology and Business UniversityBeijing 100048China Research Centre for Agri-Product Quality Traceability Beijing Technology and Business UniversityBeijing 100048China Coordination Center of China National Computer Network Emergency Response Technical TeamBeijing 100029China

This paper investigates region tracking and perimeter surveillance of second-order multiagent systems,where all agents move within a star-shaped ***,by coordination transformations,the region tracking problem is converted from the star-shaped sets to a circular *** authors employ communication and collaboration to complete region tracking and perimeter surveillance tasks,and then revert back to the star-shaped set by using inverse ***,the authors propose a distributed control strategy based on attractive and interaction potential functions,under which all agents can quickly track a given circular region and move around the ***,the authors validate the effectiveness and performance advantages of the proposed method through simulation experiments.

关键词： distributed control multi-agent systems star-shaped sets target tracking

Boundary points, minimal L^(2) integrals and concavity property Ⅱ: Weakly pseudoconvex Kähler manifolds

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Science China Mathematics 2024年第7期67卷 1665-1718页

作者： Qi’an Guan Zhitong mi Zheng Yuan School of Mathematical Sciences Peking UniversityBeijing100871China School of Mathematics and Statistics Beijing Jiaotong UniversityBeijing100044China Institute of Mathematics Academy of Mathematics and Systems ScienceChinese Academy of SciencesBeijing100190China

In this paper, we consider minimal L^(2) integrals on the sublevel sets of plurisubharmonic functions on weakly pseudoconvex K?hler manifolds with Lebesgue measurable gain related to modules at boundary points of the sublevel sets, and establish a concavity property of the minimal L^(2) integrals. As applications, we present a necessary condition for the concavity degenerating to linearity, a concavity property related to modules at inner points of the sublevel sets, an optimal support function related to modules, a strong openness property of modules and a twisted version, and an effectiveness result of the strong openness property of modules.

关键词： minimal L^(2)integrals plurisubharmonic functions boundary points weakly pseudoconvex K?hler manifold

Boundary Points,minimal L^(2)Integrals and Concavity PropertyⅢ—Linearity on Riemann Surfaces and Fibrations over Open Riemann Surfaces

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Acta Mathematica Sinica,English Series 2024年第9期40卷 2091-2152页

作者： Qi An GUAN Zhi Tong mi Zheng YUAN School of Mathematical Sciences Peking UniversityBeijing 100871P.R.China School of Mathematics and Statistics Beijing Jiaotong UniversityBeijing 100044P.R.China Institute of Mathematics Academy of Mathematics and Systems ScienceChinese Academy of SciencesBeijing 100190P.R.China

In this article,we consider a modified version of minimal L^(2) integrals on sublevel sets of plurisubharmonic functions related to modules at boundary points,and obtain a concavity property of the modified *** applications,we give characterizations for the concavity degenerating to linearity on open Riemann surfaces and on fibrations over open Riemann surfaces.

关键词： minimal L^(2)integrals plurisubharmonic functions boundary points weakly pseudoconvex Kähler manifold

distributed power conditioning unit of large-scale space solar power station

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Chinese Journal of Aeronautics 2024年第8期37卷 421-434页

作者： Xintong LI Jianwei mi Yiqun ZHANG Guanheng FAN Jie dU School of Mechano-electronic Engineering Xidian UniversityXi’an 710071China Shaanxi Key Laboratory of Space Solar Power Station System Xidian UniversityXi’an 710071China Academy of Advanced Interdisciplinary Research Xidian UniversityXi’an 710071China

In this paper,a multi-bus distributed Power Conditioning Unit(PCU)is proposed for the Space Solar Power Station with large scale photovoltaic(PV)array and power levels reaching MW *** this unit,there are multiple independent PV *** each PV array,there are multiple independent PV *** this paper,a V-P droop control method with adaptive droop coefficient is proposed,which modifies the droop intercept based on the bus voltage deviation and the power per unit value of the PV *** method ensures the accuracy of bus voltage and achieves proportional distribution of power between PV arrays based on the proposed topology structure in this *** the load changes or the output power of the PV array fluctuates,this method can ensure that power is distributed *** principle and control method of the proposed droop control method is analyzed in this *** effectiveness of the method is verified through MATLAB/Simulink simulation and *** and experimental results show that the proposed method can achieve power distributed proportionally when load changes and PV output power fluctuates,reduce bus voltage error caused by line impedance and differences in rated power of different PV arrays,and improve the performance of PV power generation system applied to space.

关键词： Space Solar Power Station Photovoltaics droop control dC confluence Power conditioning unit

Parameterization, sensitivity, and uncertainty of 1-d thermodynamic thin-ice thickness retrieval

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Acta Oceanologica Sinica 2024年第7期43卷 93-111页

作者： Tianyu Zhang Mohammed Shokr Zhida Zhang Fengming Hui Xiao Cheng Zhilun Zhang Jiechen Zhao Chunlei mi School of Geospatial Engineering and Science Sun Yat-Sen University/Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai)Zhuhai 519082China Key Laboratory of Comprehensive Observation of Polar Environment(Sun Yat-Sen University) Ministry of EducationZhuhai 519082China State Key Laboratory of Remote Sensing Science College of Global Change and Earth System ScienceBeijing Normal UniversityBeijing 100875China Science and Technology Branch Environment and Climate Change CanadaToronto M3H5T4Canada Qingdao Innovation and development Base(Centre) Harbin Engineering UniversityQingdao 266500China State Key Laboratory of Resources and Environmental Information System Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China

Retrieval of Thin-Ice Thickness(TIT)using thermodynamic modeling is sensitive to the parameterization of the independent variables(coded in the model)and the uncertainty of the measured input *** article examines the deviation of the classical model’s TIT output when using different parameterization schemes and the sensitivity of the output to the ice ***,it estimates the uncertainty of the output in response to the uncertainties of the input *** parameterized independent variables include atmospheric longwave emissivity,air density,specific heat of air,latent heat of ice,conductivity of ice,snow depth,and snow *** input parameters include air temperature,ice surface temperature,and wind *** the independent variables,the results show that the highest deviation is caused by adjusting the parameterization of snow conductivity and depth,followed ice *** sensitivity of the output TIT to ice thickness is highest when using parameterization of ice conductivity,atmospheric emissivity,and snow conductivity and *** retrieved TIT obtained using each parameterization scheme is validated using in situ measurements and satellite-retrieved *** in situ measurements,the uncertainties of the measured air temperature and surface temperature are found to be *** resulting uncertainties of TIT are evaluated using perturbations of the input data selected based on the probability distribution of the measurement *** results show that the overall uncertainty of TIT to air temperature,surface temperature,and wind speed uncertainty is around 0.09 m,0.049 m,and−0.005 m,respectively.

关键词： Arctic sea ice 1-d thermodynamic ice model thin-ice thickness sea ice parameterization

An integrated portable bio-monitoring system based on tough hydrogels for comprehensive detection of physiological activities

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Nano Research 2024年第1期17卷 321-332页

作者： Congcong Yang Chenchen Ji Fengjiao Guo Chunjiang Jin Hongyu mi Zhongchang Wang State Key Laboratory of Chemistry and Utilization of Carbon Based Energy Resources School of Chemical Engineering and TechnologyXinjiang UniversityUrumqi 830017China International Iberian Nanotechnology Laboratory(INL) Avenide Mestre Jose VeigaBraga 4715-330Portugal

Advanced soft ion-conducting hydrogels have been developed rapidly in the integrated portable health monitoring equipment due to their higher sensitivity,sensory traits,tunable conductivity,and stretchability for physiological activities and personal healthcare ***,traditional hydrogel conductors are normally susceptible to large deformation and strong mechanical stress,which leads to inferior electro-mechanical stability for real application ***,a strong ionically conductive hydrogel(poly(vinyl alcohol)-boric acid-glycerol/sodium alginate-calcium chloride/electrolyte ions(PBG/SC/EI))was designed by engineering the covalently and ionically crosslinked networks followed by the salting-out effect to further enhance the mechanical strength and ionic conductivity of the *** to the collective effects of the energy-dissipation mechanism and salting-out effect,the designed PBG/SC/EI with excellent structural integrity and robustness exhibits exceptional mechanical properties(elongation at break for 559.1%and tensile strength of 869.4 kPa)and high ionic conductivity(1.618 S·m^(-1)).As such,the PBG/SC/EI strain sensor features high sensitivity(gauge factor=2.29),which can effectively monitor various kinds of human motions(joint motions,facial micro-expression,faint respiration,and voice recognition).Meanwhile,the hydrogel-based Zn||MnO_(2)battery delivers a high capacity of 267.2 mAh·g^(-1)and a maximal energy density of 356.8 Wh·kg^(-1)associated with good cycle performance of 71.8%capacity retention after 8000 ***,an integrated bio-monitoring system with the sensor and Zn||MnO_(2)battery can accurately identify diverse physiological activities in a real-time and non-invasive *** work presents a feasible strategy for designing high-performance conductive hydrogels for highly-reliable integrated bio-monitoring systems with excellent practicability.

关键词： Ionically conductive hydrogel strain sensor Zn-based battery integrated bio-monitoring system human motion monitoring