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A restricted SIr Model with Vaccination Effect for the Epidemic Outbreaks Concerning COVID-19

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Computer Modeling in Engineering & Sciences 2023年第12期137卷 2409-2425页

作者： Ibtehal Alazman Kholoud Saad Albalawi Pranay Goswami Kuldeep Malik Department of Mathematics and Statistics College of ScienceImam Mohammad Ibn Saud Islamic UniversityRiyadh11566Saudi Arabia School of Liberal Studies Dr.B.R.Ambedkar University DelhiDelhi110006India

This paper presents a restricted SIrmathematicalmodel to analyze the evolution of a contagious infectious disease outbreak(COVID-19)using available *** new model focuses on two main concepts:first,it can present multiple waves of the disease,and second,it analyzes how far an infection can be eradicated with the help of *** stability analysis of the equilibrium points for the suggested model is initially investigated by identifying the matching equilibrium points and examining their *** basic reproduction number is calculated,and the positivity of the solutions is *** simulations are performed to determine if it is multipeak and evaluate vaccination’s *** addition,the proposed model is compared to the literature already published and the effectiveness of vaccination has been recorded.

关键词： restricted SIr model equilibrium points and stability numerical simulation

Enhancing Image Description Generation through Deep reinforcement Learning:Fusing Multiple Visual Features and reward Mechanisms

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Computers, Materials & Continua 2024年第2期78卷 2469-2489页

作者： Yan Li Qiyuan Wang Kaidi Jia School of Cyber Security Gansu University of Political Science and LawLanzhou730070China

Image description task is the intersection of computer vision and natural language processing,and it has important prospects,including helping computers understand images and obtaining information for the visually *** study presents an innovative approach employing deep reinforcement learning to enhance the accuracy of natural language descriptions of *** method focuses on refining the reward function in deep reinforcement learning,facilitating the generation of precise descriptions by aligning visual and textual features more *** approach comprises three key ***,it utilizes residual Network 101(resNet-101)and Faster region-based Convolutional Neural Network(Faster r-CNN)to extract average and local image features,respectively,followed by the implementation of a dual attention mechanism for intricate feature ***,the Transformer model is engaged to derive contextual semantic features from textual ***,the generation of descriptive text is executed through a two-layer long short-term memory network(LSTM),directed by the value and reward *** with the image description method that relies on deep learning,the score of bilingual Evaluation Understudy(bLEU-1)is 0.762,which is 1.6%higher,and the score of bLEU-4 is ***-based Image Description Evaluation(CIDEr)scored 0.998,recall-Oriented Understudy for Gisting Evaluation(rOUGE)scored 0.552,the latter improved by 0.36%.These results not only attest to the viability of our approach but also highlight its superiority in the realm of image *** research can explore the integration of our method with other artificial intelligence(AI)domains,such as emotional AI,to create more nuanced and context-aware systems.

关键词： Image description deep reinforcement learning attention mechanism

Stochastic programming based coordinated expansion planning of generation,transmission,demand side resources,and energy storage considering the DC transmission system

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Global Energy Interconnection 2024年第1期7卷 25-37页

作者： Liang Lu Mingkui Wei Yuxuan Tao Qing Wang Yuxiao Yang Chuan He Haonan Zhang Southwest branch of State Grid Corporation of China Chengdu 610065P.R.China college of Electrical Engineering Sichuan UniversityChengdu 610065P.R.China

With the increasing penetration of wind and solar energies,the accompanying uncertainty that propagates in the system places higher requirements on the expansion planning of power systems.A source-grid-load-storage coordinated expansion planning model based on stochastic programming was proposed to suppress the impact of wind and solar energy *** types of system components,including demand response service entities,converter stations,DC transmission systems,cascade hydropower stations,and other traditional components,have been extensively ***,energy storage systems are considered to improve the accommodation level of renewable energy and alleviate the influence of ***-response service entities from the load side are used to reduce and move the demand during peak load *** uncertainties in wind,solar energy,and loads were simulated using stochastic ***,the effectiveness of the proposed model is verified through numerical simulations.

关键词： Hydro-wind-solar complementary Expansion planning Demand response Energy storage system Source-network-demand-storage coordination

Control method based on drFNN sliding mode for multifunctional flexible multistate switch

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Global Energy Interconnection 2024年第2期7卷 190-205页

作者： Jianghua Liao Wei Gao Yan Yang Gengjie Yang college of Electrical Engineering and Automation Fuzhou UniversityFuzhou 350108P.R.China Faculty of Automation Huaiyin Institute of Technology Huai’an 223003P.R.China

To address the low accuracy and stability when applying classical control theory in distribution networks with distributed generation,a control method involving flexible multistate switches(FMSs)is proposed in this *** approach is based on an improved double-loop recursive fuzzy neural network(drFNN)sliding mode,which is intended to stably achieve multiterminal power interaction and adaptive arc suppression for single-phase ground ***,an improved drFNN sliding mode control(SMC)method is proposed to overcome the chattering and transient overshoot inherent in the classical SMC and reduce the reliance on a precise mathematical model of the control *** improve the robustness of the system,an adaptive parameter-adjustment strategy for the drFNN is designed,where its dynamic mapping capabilities are leveraged to improve the transient compensation ***,a quasi-continuous second-order sliding mode controller with a calculus-driven sliding mode surface is developed to improve the current monitoring accuracy and enhance the system *** stability of the proposed method and the convergence of the network parameters are verified using the Lyapunov theorem.A simulation model of the three-port FMS with its control system is constructed in MATLAb/*** simulation result confirms the feasibility and effectiveness of the proposed control strategy based on a comparative analysis.

关键词： Distribution networks Flexible multistate switch Grounding fault arc suppression Double-loop recursive fuzzy neural network Quasi-continuous second-order sliding mode

Structural evolution and zero-field SMM behaviour in ferromagnetically-coupled disk-type Co_(7)clusters bearing exclusively end-on azido bridges

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Chinese Chemical Letters 2024年第8期35卷 567-571页

作者： Yijia Jiao Yuzhu Li Yuting Zhou Peipei Cen Yi Ding Yan Guo Xiangyu Liu State Key Laboratory of High-efficiency Utilization of Coal and Green Chemical Engineering College of Chemistry and Chemical EngineeringNingxia UniversityYinchuan 750021China b college of Public Health College of Basic Medical ScienceNingxia Medical UniversityYinchuan 750021China

Concise chemistry leads to a family of heptanuclear Co^(Ⅱ)-clusters,[Co_(7)(N_(3))_(12)(CH_(3)CN)_(12)][Y_(2)(NO_(3))_(4)(piv)_(4)]·2CH_(3)CN(DC1)(pivH=pivalic acid),[Co_(7)(N_(3))_(12)(CH_(3)CN)_(10)(NO_(3))_(0.4)(Cl)_(1.6)]·4CH_(3)CN(DC2)and[Co_(7)(N_(3))_(12)(CH_(3)CN)_(10)(NO_(3))_(2)]·4CH_(3)CN(DC3),in which the metal ions are exclusively bridged by end-on azido ligands to stabilize a beautiful disk-like *** resulting clusters exhibit interesting structural transformations and thermodynamically-distinct steady states verified by theoretical *** studies reveal the first observation of zero-field SMM behaviour in disk-like heptanuclear Co^(Ⅱ)complexes.

关键词： Multinuclear Co^(Ⅱ)-clusters Disk-like motif Structural modulation Ferromagnetic coupling Zero-field SMM

bifurcation analysis of a diffusive predator-prey model with hyperbolic mortality and prey-taxis

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International Journal of biomathematics 2024年第1期17卷 251-264页

作者： Yan Li Zhiyi Lv Fengrong Zhang Hui Hao college of Science China University of Petroleum(East China)Qingdao 266580P.R.China

In this paper,we study a diffusive predator-prey model with hyperbolic mortality and prey-taxis under homogeneous Neumann boundary *** first analyze the influence of prey-taxis on the local stability of constant *** turns out that prey-taxis has influence on the stability of the unique positive constant equilibrium,but has no influence on the stability of the trivial equilibrium and the semi-trivial *** then derive Hopf bifurcation and steady state bifurcation related to prey-taxis,which imply that the prey-taxis plays an important role in the dynamics.

关键词： Predator-prey model prey-taxis Hopf bifurcation steady state bifurcation

Global dynamics of a tumor-immune model with an immune checkpoint inhibitor

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International Journal of biomathematics 2024年第5期17卷 205-228页

作者： Fangfang He Huiyan Zhu Jinzhang Lin Yingchen Ou college of Mathematics and Physics University of South China Hengyang Hunan 421001P.R.China

In this paper,a mathematical ordinary differential tumor-immune model is proposed based on an immune checkpoint inhibitor,which is an innovative method for tumor *** important factors in tumor-immune response are the programmed cell death protein 1(PD-1)and its ligand *** model consists of three populations:tumor cells,activated T cells and *** analyzing the dynamics of the model,it is found that there is always a unique tumor-free equilibrium and at most two tumor interior *** nonexistence of nontrivial positive periodic orbits is established by using the new Dulac function,and then a global dynamics of the model is *** conclusions of our analysis show that increasing the possibility of T cells killing tumor cells(p),early detection of tumor cells,or the use of PD-1 inhibitors to activate T cells are effective in eliminating tumor cells.

关键词： Tumor-immune model immune checkpoint inhibitor PD-1 PD-L1 anti-PD-1

The dynamics of traveling wavefronts for a model describing host tissue degradation by bacteria

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International Journal of biomathematics 2024年第3期17卷 265-287页

作者： Xing-Xing Yang Guo-bao Zhang Ge Tian college of Mathematics and Statistics Northwest Normal University Lanzhou Gansu 730070P.R.China

In this paper,we mainly investigate the dynamics of traveling wavefronts for a model describing host tissue degradation by *** first establish the existence of spreading speed,and show that the spreading speed coincides with the minimal wave speed of traveling ***,a lower bound estimate of the spreading speed is ***,we prove that the traveling wavefronts with large speeds are globally exponentially stable,when the initial perturbation around the traveling wavefronts decays exponentially asχ→-∞,but the initial perturbation can be arbitrarily large in other *** adopted methods are the weighted energy and the squeezing technique.

关键词： Host tissue degradation bacterial infection traveling wavefronts minimal wave speed stability

Oscillatory solutions in a 3D predation system with time delay and age structure

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International Journal of biomathematics 2024年第5期17卷 133-175页

作者： Peng Yang college of Mathematics and Statistics Northwest Normal University Lanzhou Gansu 730070P.R.China

This paper is concerned with the sustained periodic oscillation phenomenon in a threespecies delayed predation system with Holling type II functional response and age structure in top *** top predator fertility function is regarded as a piecewise continuous smooth function with regard to their maturation period *** complicated dynamic behavior is proved by integrated semigroup theory and Hopf bifurcation theorem for semilinear equations with non-dense *** qualitative analysis and bifurcation study of the system,we yield that this system has a nontrivial periodic solution that bifurcates from the positive equilibrium age distribution when bifurcation parameter T passes through some critical *** simulations are also provided to illustrate theoretically analytical results.

关键词： Periodic oscillations 3D predation system time delay age structure integrated semigroup