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Locally and globally uniform approximations for ruin probabilities of a nonstandard bidimensional risk model with subexponential claims

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Applied Mathematics(A Journal of Chinese Universities) 2024年第1期39卷 98-113页

作者： LIU zai-ming GENG Bing-zhen WANG Shi-jie School of Mathematics and Statistics Central South UniversityChangsha 410083China School of Big Data and Statistics Anhui UniversityHefei 230601China

Consider a nonstandard continuous-time bidimensional risk model with constant force of interest,in which the two classes of claims with subexponential distributions satisfy a general dependence structure and each pair of the claim-inter-arrival times is arbitrarily *** some mild conditions,we achieve a locally uniform approximation of the finite-time ruin probability for all time horizon within a finite *** we further assume that each pair of the claim-inter-arrival times is negative quadrant dependent and the two classes of claims are consistently-varying-tailed,it shows that the above obtained approximation is also globally uniform for all time horizon within an infinite interval.

关键词： bidimensional risk model asymptotic formula subexponential distribution consistently varying tail ruin probability

Hydrothermal synthesis and photoluminescence behavior of CeO_2 nanowires with the aid of surfactant PVP

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International Journal of Minerals,Metallurgy and Materials 2010年第4期17卷 470-474页

作者： ming-zai wu Yan-mei Liu Peng Dai Zhao-qi Sun Xian-song Liu Key Laboratory of Opto-electronic Information Acquisition and Manipulation Anhui University Hefei 230039 China Engineering Technology Research Center of Magnetic Materials Anhui University Hefei 230039 China

Well-crystalline CeO_2 nanowires were prepared via a surfactant-assisted hydrothermal *** temperature and reaction time were changed for the determination of optimal synthesis *** as-obtained products were characterized by X-ray diffraction （XRD）,high-resolution transmission electron microscopy（HRTEM）,and field emission scanning electron microscopy（FESEM）.The results show that single crystal CeO_2 nanowires with high yield and good uniformity can be obtained hydrothermally at 180℃for 12 h with the aid of 2.0 g surfactant（polyvinyl pyrrolidone,PVP）.The role of PVP was then discussed and a possible growth mechanism was proposed. Moreover,room temperature photoluminescence（PL） spectra were obtained for these CeO2 nanowires,which are believed to be related to the abundant defects in these nanostructures.

关键词： cerium oxide polyvinyl pyrrolidone hydrothermal photoluminescence

New low-rank optimization model and algorithms for spectral compressed sensing

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Science China Mathematics 2024年

作者： zai Yang Xunmeng wu Zongben Xu School of Mathematics and Statistics Xi'an Jiaotong University

In this paper,we investigate the recovery of an undamped spectrally sparse signal and its spectral components from a set of regularly spaced samples within the framework of spectral compressed sensing and *** show that the existing Hankel-based optimization methods suffer from the fundamental limitation that the prior of undampedness cannot be *** propose a new low-rank optimization model partially inspired by forward-backward processing for line spectral estimation and show its capability to restrict the spectral poles to the unit *** present convex relaxation approaches with the model and show their provable accuracy and robustness to bounded and sparse *** our results are generalized from one-dimensional to arbitrary-dimensional spectral compressed *** simulations are provided to corroborate our analysis and show the efficiency of our model and the advantageous performance of our approach in terms of accuracy and resolution compared with the state-of-the-art Hankel and atomic norm methods.

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Brain Cognition Mechanism-Inspired Hierarchical Navigation Method for Mobile Robots

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Journal of Bionic Engineering 2024年第2期21卷 852-865页

作者： Qiang Zou Chengdong wu ming Cong Dong Liu Faculty of Robot Science and Engineering Northeastern UniversityShenyang110819China School of Mechanical Engineering Dalian University of TechnologyDalian116024China

Autonomous navigation is a fundamental problem in *** methods generally build point cloud map or dense feature map in perceptual space;due to lack of cognition and memory formation mechanism,traditional methods exist poor robustness and low cognitive *** a new navigation technology that draws inspiration from mammal’s navigation,bionic navigation method can map perceptual information into cognitive space,and have strong autonomy and environment *** improve the robot’s autonomous navigation ability,this paper proposes a cognitive map-based hierarchical navigation ***,the mammals’navigation-related grid cells and head direction cells are modeled to provide the robots with location *** then a global path planning strategy based on cognitive map is proposed,which can anticipate one preferred global path to the target with high efficiency and short ***,a hierarchical motion controlling method is proposed,with which the target navigation can be divided into several sub-target navigation,and the mobile robot can reach to these sub-targets with high confidence ***,some experiments are implemented,the results show that the proposed path planning method can avoid passing through obstacles and obtain one preferred global path to the target with high efficiency,and the time cost does not increase extremely with the increase of experience nodes *** motion controlling results show that the mobile robot can arrive at the target successfully only depending on its self-motion information,which is an effective attempt and reflects strong bionic properties.

关键词： Bionic navigation Spatial localization cells Global path planning Hierarchical motion controlling

Tighter sum uncertainty relations via(α,β,γ)weighted Wigner–Yanase–Dyson skew information

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Communications in Theoretical Physics 2024年第3期76卷 91-99页

作者： Cong Xu Zhaoqi wu Shao-ming Fei School of Mathematical Sciences Capital Normal UniversityBeijing 100048China Department of Mathematics Nanchang UniversityNanchang 330031China Max-Planck-Institute for Mathematics in the Sciences 04103 LeipzigGermany

We establish tighter uncertainty relations for arbitrary finite observables via(α,β,γ)weighted Wigner–Yanase–Dyson((α,β,γ)WWYD)skew *** results are also applicable to the(α,γ)weighted Wigner–Yanase–Dyson((α,γ)WWYD)skew information and the weighted Wigner–Yanase–Dyson(WWYD)skew *** also present tighter lower bounds for quantum channels and unitary channels via(α,β,γ)modified weighted Wigner–Yanase–Dyson((α,β,γ)MWWYD)skew *** examples are provided to illustrate the tightness of our uncertainty relations.

关键词： quantum channels (α,β,γ)WWYD skew information (α,β,γ)MWWYD skew information uncertainty relations

Hybrid Network Model Based on Data Enhancement for Short-term Power Prediction of New PV Plants

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Journal of Modern Power Systems and Clean Energy 2024年第1期12卷 77-88页

作者： Shangpeng Zhong Xiaoming Wang Bin Xu Hongbin wu ming Ding the Anhui Province Key Laboratory of Renewable Energy Utilization and Energy Saving Hefei University of TechnologyHefei 230009China the State Grid Anhui Electric Power Research Institute Hefei 230061China

This study proposes a hybrid network model based on data enhancement to address the problem of low accuracy in photovoltaic(PV)power prediction that arises due to insuffi cient data samples for new PV ***,a time-series gener ative adversarial network(TimeGAN)is used to learn the distri bution law of the original PV data samples and the temporal correlations between their features,and these are then used to generate new samples to enhance the training ***,a hybrid network model that fuses bi-directional long-short term memory(BiLSTM)network with attention mechanism(AM)in the framework of deep&cross network(DCN)is con structed to effectively extract deep information from the origi nal features while enhancing the impact of important informa tion on the prediction ***,the hyperparameters in the hybrid network model are optimized using the whale optimi zation algorithm(WOA),which prevents the network model from falling into a local optimum and gives the best prediction *** simulation results show that after data enhance ment by TimeGAN,the hybrid prediction model proposed in this paper can effectively improve the accuracy of short-term PV power prediction and has wide applicability.

关键词： New photovoltaic(PV)plant short-term predic tion time-series generative adversarial network(TimeGAN) hy brid network hyperparameter

Skin Microbiota and the Skin Barrier

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International Journal of Dermatology and Venereology 2024年第1期7卷 18-26页

作者： ming-Yang wu Xu Yao Department of Allergy and Rheumatology Jiangsu Key Laboratory of Molecular Biology for Skin Diseases and STIsHospital for Skin Diseases(Institute of Dermatology)Chinese Academy of Medical Sciences and Peking Union Medical CollegeNanjingJiangsu 210042China Jiangsu Key Laboratory of Molecular Biology for Skin Diseases and STIs NanjingJiangsu 210042China

The skin constitutes the primary barrier between the human body and the external *** skin microbiome plays an important role in the microecosystem on the skin surface and mediates multiple facets of the skin barrier function,including physical,chemical,microbial,and immune *** this review,we discuss the host-microbiota interactions in barrier maintenance and disruption,implications for skin disorders such as atopic dermatitis,psoriasis,and rosacea,and the latest strategies for targeting the skin microbiota to improve the skin barrier.

关键词： skin barrier microbiota immune atopic dermatitis

Thermodynamic geometry of the RN-Ad S black hole and non-local observables

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Communications in Theoretical Physics 2024年第2期76卷 137-144页

作者： Chao Wang Bin wu Zhen-ming Xu Wen-Li Yang Institute of Physics Shaanxi University of TechnologyHanzhong 723000China School of Physics Northwest UniversityXi'an 710127China Institute of Modern Physics Northwest UniversityXi'an 710127China Shaanxi Key Laboratory for Theoretical Physics Frontiers Xi'an 710127China Peng Huanwu Center for Fundamental Theory Xi'an 710127China

This paper studies the thermodynamic geometry of the Reissner–Nordstr?m-anti-de Sitter(RN-AdS)black hole via detection of the non-local observables in the dual field theory,including the entanglement entropy and equal-time two-point correlation *** the dimensional analysis,we construct the principle of corresponding states of black hole *** a result,our findings can be applied to black holes with different Ad S *** this sense,the probe of the thermodynamic geometry of the RN-Ad S black hole though the non-local observables in dual field theory has been confirmed numerically.

关键词： black hole thermodynamic thermodynamic geometry phase transition non-local observables

Geometric error measuring,modeling,and compensation for CNC machine tools:A review

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Chinese Journal of Aeronautics 2024年第2期37卷 163-198页

作者： Zhao ZHANG Feng JIANG ming LUO Baohai wu Dinghua ZHANG Kai TANG Engineering Research Center of Advanced Manufacturing Technology for Aero Engine(Northwestern Polytechnical University) Ministry of EducationXi’an 710072China Key Laboratory of High Performance Manufacturing for Aero Engine(Northwestern Polytechnical University) Ministry of Industry and Information TechnologyXi’an 710072China Department of Mechanical and Aerospace Engineering Hong Kong University of Science and TechnologyHong KongChina

Geometric error,mainly due to imperfect geometry and dimensions of machine components,is one of the major error sources of machine *** that geometric error has significant effects on the machining quality of manufactured parts,it has been a popular topic for academic and industrial research for many years.A great deal of research work has been carried out since the 1970s for solving the problem and improving the machining *** have studied how to measure,detect,model,identify,reduce,and compensate the geometric *** paper presents a thorough review of the latest research activities and gives an overview of the state of the art in understanding changes in machine tool performance due to geometric *** advances in measuring the geometrical errors of machine tools are summarized,and different kinds of error identification methods of translational axes and rotation axes are illustrated ***,volumetric geometric error modeling,tracing,and compensation techniques for five-axis machine tools are emphatically ***,research challenges in order to improve the volumetric accuracy of machine tools are also highlighted.

关键词： Error compensation Error identification Error measurement Error modeling Geometric error Machine tools