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Periodic Solutions of Singular Second Order Equations at Resonance

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Acta Mathematica Sinica,English Series 2015年第10期31卷 1599-1610页

作者： yin yin WU Ding Bian QIAN School of Mathematical Sciences Soochow University Department of Fondamental Courses Wuxi Institute of Technology

In this paper, we study the existence of positive periodic solutions for singular second order equations x＂＋ n2/4＋h（x） = p（t）, where h has a singularity at the origin and n is a positive integer. We give an explicit condition to ensure the existence of positive periodic solutions when h is an unbounded perturbation at infinity by using qualitative analysis and topological dezree theory.

关键词： Second order equations singularity periodic solutions resonance unbounded perturba-tions

Cerium oxide nanoparticles-mediated cascade catalytic chemo-photo tumor combination therapy

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Nano Research 2022年第1期15卷 333-345页

作者： Zitao Hu yin Ding State Key Laboratory of Analytical Chemistry for Life Science School of Chemistry and Chemical EngineeringNanjing UniversityNanjing 210093China

ROS-based tumor therapy based on nanocatalytic medicine has recently been proposed for its ***,a safe and highly efficient strategy towards getting high enough ROS to kill the hypoxic cancer cells is still a great ***,we report a simple pH/H_()20_(2)-activatable,O_(2)-evolving,and ROS regulating doxorubicin(DOX)and indocyanine green(ICG)co-loading PEGylated polyaniline(PANI)coated CeOx@polyacrylic acid(PAA)nanoclusters for highly selective and optimized cancer combination *** can selectively and greatly enhance intracellular O_(2) and ROS levels in tumor region,which depends on two-step catalytic properties of nanoceria(Ce^(4+)/Ce^(3+)=3.46,neutral surface charge,mostly localize into the cytoplasm,pH 7.4-6.5,catalase-like catalytic agents convert to Ce^(4+)/Ce^(3+)=0.58,negative surface charge,mostly localize into the lysosomes,pH 5-4,oxidase-like catalytic agents,triggered by near infrared(NIA)laser irradiation).Furthermore,the protective effect of polyethylene glycol(PEG),PANI,and PAA ensure that the nanoceria can only play the role of catalase under the irradiation of NIR light arrived at the tumor ***,loading of nanoceria and ICG onto PANI greatly enhanced photo thermal effect of nanoparticles.(NPs),which is useful for killing cancer cells by relieving hypoxia and promoting cross-membrane drug *** further enhance photodynamic therapy and chemotherapy *** chemo-photo combination therapies fantastically inhibited tumor growth and prevented tumor recurrence in vivo,suggesting a smart nanotheranostic system to achieve more precise and effective therapies in O_(2)-deprived tumor tissue.

关键词： nanocatalytic medicine photodynamic therapy hypoxia cerium oxide@polyaniline combination therapy

Hydrogen and nitrogen absorption properties of Ce-added Zr_(2)(Fe_(1-x)Ni_(x)) alloys

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Journal of Rare Earths 2024年第6期42卷 1136-1141,I0005页

作者： Kai yin Xiaopeng Liu State Key Laboratory of Advanced Materials for Smart Sensing GRINM Group Co.Ltd.Beijing10088China GRIMAT Engineering Institute Co. Ltd.Beijing101407China General Research Institute of Nonferrous Metals Beijing100088China

To improve the nitriding resistance of Zr_(2)Fe alloy,the Ce-added Zr_(2)(Fe_(1-x)Ni_(x))(x=0,0.15,0.3,0.5)alloys were prepared by magnetic levitation melting *** effects of Ni substitution for Fe on the phase structure,hydrogen and nitrogen absorption properties of the alloys were investigated by X-ray diffraction,scanning electron microscopy and p-c isotherm *** experimental results show that Ni substitution can effectively inhibit the formation of both α-Zr and ZrFe_(2) phases and promote the formation of C16 structure Zr_(2)(Fe,Ni)phase,causing Ni-substituted alloys to exhibit low nitrogen absorption rate and *** 623 K under 0.5 MPa nitrogen pressure,the nitrogen absorption capacity of Ce-added Zr_(2)(Fe_(0.5)Ni_(0.5))alloy reaches to 0.8 mL/g,much lower than that of Zr_(2)Fe alloy(1.5 mL/g).Ni substitution decreases the crystal cell volume of the C_(16)Zr_(2)(Fe,Ni)phase,resulting in an increase in the hydrogen absorption equilibrium *** 623 K under 0.05 MPa hydrogen pressure,the hydrogen absorption capacity decreases from 1.46 wt%of Zr_(2)Fe alloy to 1.41 wt%of Ce-added Zr_(2)(Fe_(0.5)Ni_(0.5))alloy.

关键词： Zr_(2)Fe alloy Ce Pressure-composition isotherm Hydrogen absorption Nitrogen absorption Rare earths

Standard model of knowledge representation

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Frontiers of Mechanical Engineering 2016年第3期11卷 275-288页

作者： Wensheng yin School of Mechanical Science and Engineering Huazhong University of Science and Technology Wuhan 430074 China

Knowledge representation is the core of artificial intelligence research. Knowledge representation methods include predicate logic, semantic network, computer programming language, database, mathematical model, graphics language, natural language, etc. To establish the intrinsic link between various knowledge representation methods, a unified knowledge representa- tion model is necessary. According to ontology, system theory, and control theory, a standard model of knowledge representation that reflects the change of the objective world is proposed. The model is composed of input, processing, and output. This knowledge representation method is not a contradiction to the traditional knowledge representation method. It can express knowledge in terms of multivariate and multidimensional. It can also express process knowledge, and at the same time, it has a strong ability to solve problems. In addition, the standard model of knowledge representation provides a way to solve problems of non-precision and inconsistent knowledge.

关键词： knowledge representation standard model ontology system theory control theory multidimensional representation

Video-Driven 2D Character Animation

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Chinese Journal of Electronics 2021年第6期30卷 1038-1048页

作者： yin Qinran CAO Weiqun School of Information Science and Technology Beijing Forestry University Engineering Research Center for Forestry-oriented Intelligent Information Processing of National Forestry and Grassland Administration

Video-driven animation has always been a hot and challenging topic in the field of computer animation. We propose a method of mapping a sequence of human skeletal keypoints in a video onto a two-dimensional character to generate 2 D character animation. For a given two-dimensional character picture, we extract the motion of real human in video data, driving the character deformation. We analyze common two-dimensional human body movements, classify the basic posture of the human body, realize the recognition of skeleton posture based on back propagation network, capture human body motion by automatically tracking the position of the human skeleton keypoints coordinates in the video and redirect the motion data to a 2 D character. Compared with the traditional method, our work is less affected by video data illumination and background complexity. We calibrate human body motion in videos to a 2 D character according to the skeleton topology to avoid motion distortion caused by the difference in skeleton size and ratio. The experimental results show that the proposed algorithm can generate the motion of two-dimensional characters based on the motion of human characters in video data. The animation is natural and smooth, and the algorithm has strong robustness.

关键词： two-dimensional character picture motion distortion skeleton size video data illumination human characters video signal processing computer animation character deformation basic posture two-dimensional human body movements background complexity hot topic motion data video-driven animation computational geometry human skeleton keypoints skeleton topology skeleton posture human skeletal keypoints video-driven 2D character animation capture human body motion

Energy Efficient Predictive Control for Vapor Compression Refrigeration Cycle Systems

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IEEE/CAA Journal of Automatica Sinica 2018年第5期5卷 953-960页

作者： Xiaohong yin Shaoyuan Li the School of Automation and Electronic Engineering Qingdao University of Science and TechnologyQingdao 266042China the Department of Automation Shanghai Jiao Tong Universityand the Key Laboratory of System Control and Information ProcessingMinistry of Education of ChinaShanghai 200240China

Abstract--Vapor compression refrigeration cycle （VCC） system is a high dimensional coupling thermodynamic system for which the controller design is a great challenge. In this paper, a model predictive control based energy efficient control strategy which aims at maximizing the system efficiency is proposed. Firstly, according to the mass and energy conservation law, an analysis on the nonlinear relationship between superheat and cooling load is carried out, which can produce the maximal effect on the system performance. Then a model predictive control （MPC） based controller is developed for tracking the calculated setting curve of superheat degree and pressure difference based on model identified from data which can be obtained from an experimental rig. The proposed control strategy maximizes the coefficient of performance （COP） which depends on operating conditions, in the meantime, it meets the changing demands of cooling capacity. The effectiveness of the control performance is validated on the experimental rig. Index Terms--Cooling load, model predictive control （MPC）, superheat, vapor compression refrigeration cycle （VCC）.

关键词： Cooling load model predictive control(MPC) superheat vapor compression refrigeration cycle(VCC)

Hydrothermal preparation of Nb-doped NaTaO_(3) with enhanced photocatalytic activity for removal of organic dye

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Chinese Journal of Chemical Engineering 2022年第6期35卷 142-149页

作者： Hao Zhou Qi yin State Key Laboratory of Clean Energy Utilization Zhejiang UniversityHangzhou 310027China

The construction of efficient photocatalysts has received much attention in wastewater *** this study,Nb-doped NaTaO_(3) was prepared with different doping ratio by a facile hydrothermal *** prepared catalysts were analyzed by X-ray diffraction,scanning electron microscopy,Brunauer-EmmettTeller(BET)theory,ultraviolet–visible diffuse reflectance *** the synthesized catalysts were employed to degrade a model pollutant,methylene blue(MB),under a 250 W mercury *** characterization tests confirm that Nb was successfully doped into the crystal structure of NaTaO_(3) and the modified NaNb_(x)Ta_(1)·xO_(3)(x is the doping ratio;x=0.25,0.5,0.75)samples were formed,which were in regular cubic shapes just like pure NaTaO_(3).The synthesized NaNb_(x)Ta_(1)·xO_(3)(x=0.25,0.5,0.75)had improved specific surface area and narrowed band gaps compared with pure NaTaO_(3).In photocatalytic degradation experiments,NaNb0.75Ta0.25O_(3) presented the best photocatalytic activity ascribed to the narrow band gap and the high surface area,degradating 95.7%of MB after 180 min of reaction,which was even twice the ability of pure NaTaO_(3).Besides,the effects of possible inorganic anions and cations in wastewater on photocatalytic degradation were *** spin resonance(ESR)tests and capture experiments were also conducted and a possible photocatalytic mechanism was *** work provides a direction for constructing superior NaTaO_(3)-based photocatalysts to be widely utilized in environmental protection.

关键词： Photocatalytic degradation Methylene blue NaTaO_(3)

Crime Prediction Methods Based on Machine Learning:A Survey

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Computers, Materials & Continua 2023年第2期74卷 4601-4629页

作者： Junxiang yin School of Social Science University of ManchesterM139PL Oxford RoadManchesterUK

The objective of crime prediction,one of the most important technologies in social computing,is to extract useful information from many existing criminal records to predict the next process-related *** can aid the police in obtaining criminal information and warn the public to be vigilant in certain *** the rapid growth of big data,the Internet of Things,and other technologies,as well as the increasing use of artificial intelligence in forecasting models,crime prediction models based on deep learning techniques are ***,it is necessary to classify the existing crime prediction algorithms and compare in depth the attributes and conditions that play an essential role in the analysis of crime prediction *** crime prediction methods can be roughly divided into two categories:those based on conventional machine learning and those based on contemporary deep *** survey analyses the fundamental theories and *** most frequently used data sets are then enumerated,and the fundamental procedures of various algorithms are also analyzed in this *** light of the insufficient scale of existing data in this field,the ambiguity of data types used to predict crimes,and the absence of public data sets that have a significant impact on the research of algorithm models,this survey proposes the construction of a machine learning-based big data research model to address these *** researchers who will enter this field are provided with a guide to the direction of future research development.

关键词： Crime prediction machine learning artificial intelligence deep learning

Comparison theorems on Finsler manifolds with weighted Ricci curvature bounded below

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Frontiers of Mathematics in China 2018年第2期13卷 435-448页

作者： Songting yin Department of Mathematics and Computer Science Tongling University Tongling 244000China

We obtain the Laplacian comparison theorem and the Bishop- Gromov comparison theorem on a Finsler manifold with the weighted Ricci curvature Ric∞ bounded below. As applications, we prove that if the weighted Ricci curvature Ri∞ is bounded below by a positive number, then the manifold must have finite fundamental group, and must be compact if the distortion is also bounded. Moreover, we give the Calabi-Yau linear volume growth theorem on a Finsler manifold with nonnegative weighted Ricci curvature.

关键词： Finsler manifold distortion S-curvature weighted Ricci curvature,comparison theorem