Article
Mathematics, Applied
Soufiane Bentout, Salih Djilali, Abdon Atangana
Summary: In this study, an age-structured prey-predator model with infection was proposed to examine the effect of predator maturation age on the interaction between predator and prey, as well as the spread of infectious disease. It was found that the minimal maturation duration can impact the behavior of the solution, potentially leading to periodic solutions generated by Hopf bifurcation for three different equilibrium states. The mathematical results were numerically validated using graphical illustrations.
MATHEMATICAL METHODS IN THE APPLIED SCIENCES
(2022)
Article
Multidisciplinary Sciences
Fernando W. Rossine, Gabriel T. Vercelli, Corina E. Tarnita, Thomas Gregor
Summary: This study reveals the foraging strategy of amoebae, a common protozoan predator in soil, and identifies amoebae mobility as the key determinant of predation efficiency. The findings provide insights into the role of protozoan predators in microbial soil ecosystems.
PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
(2022)
Article
Mathematics, Interdisciplinary Applications
Jose J. Oliveira
Summary: This paper provides sufficient conditions for the global asymptotic stability of a general n-dimensional nonautonomous and nonlinear differential equation with infinite delay. The main stability criterion depends on the delay size on the linear part and the dominance of linear terms over nonlinear terms. The obtained theoretical stability results are applied to answer open problems and generalize a bidirectional associative memory neural network model with delays. A numerical example is given to illustrate the novelty of the results.
CHAOS SOLITONS & FRACTALS
(2022)
Article
Computer Science, Interdisciplinary Applications
Nirapada Santra, Sangeeta Saha, Guruprasad Samanta
Summary: This paper explores a stage-structured predator-prey model in a toxic environment, highlighting the impact of toxic substances and time delays on species growth. The study discusses the positivity and boundedness of solutions. Analytical and numerical simulations reveal that the coexistence equilibrium point is stable at low and moderate delay parameters associated with predator's maturity. However, a longer maturity duration may lead to predator species extinction. The paper also investigates the impact of toxicity on the system, finding that stability switches as the time delay and changes in toxicity vary.
MATHEMATICS AND COMPUTERS IN SIMULATION
(2023)
Article
Mathematics
Yang Sun, Gui-Lai Zhang, Zhi-Wei Wang, Tao Liu, M. Filomena Teodoro, Marina Alexandra Pedro Andrade, Youssef Raffoul
Summary: This paper focuses on a fixed stepsize Euler method for linear impulsive neutral delay differential equations. By selecting partition nodes and using linear interpolation, the method's convergence of order one is rigorously proven. Two examples are provided to illustrate its efficiency.
Article
Mathematics
Yuan Yuan, Xianlong Fu
Summary: This paper focuses on the asymptotic behavior of an age-structured prey-predator model with distributed delay. The existence of positive stationary solutions is discussed and the linearization process is applied. The stability/instability, asynchronous exponential growth, and Hopf bifurcations of the linearized system are investigated using operator semigroups theory and spectral analysis.
JOURNAL OF DIFFERENTIAL EQUATIONS
(2022)
Article
Mathematics, Applied
Changjin Xu, Wei Zhang, Chaouki Aouiti, Zixin Liu, Lingyun Yao
Summary: In this study, a fractional-order stage-structured predator-prey system with distributed and discrete time delays is investigated. By variable transformation, an isovalent version of the system is obtained, which includes both fractional-order and integer-order equations. A novel delay-independent bifurcation condition is established to ensure the appearance of Hopf bifurcation, and the impact of time delay on stability and bifurcation is revealed. Numerical simulations support the derived conclusions.
MATHEMATICAL METHODS IN THE APPLIED SCIENCES
(2023)
Article
Automation & Control Systems
Wenjie Li, Jinchen Ji, Lihong Huang
Summary: This paper investigates the global dynamics of a water hyacinth-fish ecological system under ratio-dependent state impulsive control. The study analyzes the positivity and boundedness of the controlled system's solution and explores the local stability of the equilibrium. Theoretical results are verified through examples, confirming their correctness and validity.
JOURNAL OF THE FRANKLIN INSTITUTE-ENGINEERING AND APPLIED MATHEMATICS
(2022)
Article
Mathematics
Maria A. Skvortsova
Summary: This study focuses on a system of differential equations with two delays that describes the interaction between plankton and fish. The research analyzes the asymptotic stability of the equilibrium point corresponding to the presence of only phytoplankton, and establishes estimates characterizing the stabilization rate at infinity to this equilibrium point. The results are obtained using Lyapunov-Krasovskii functionals.
Article
Engineering, Multidisciplinary
Osama Moaaz, Ali Muhib, Mohammed Zakarya, Abdel-Haleem Abdel-Aty
Summary: This work provides sufficient conditions for the oscillation of all solutions of fourth-order delay differential equations with non-canonical operator by establishing conditions for nonexistence of positive solutions. The results significantly extend and complement existing ones in the field. Production and hosting by Elsevier B.V. on behalf of Faculty of Engineering, Alexandria University.
ALEXANDRIA ENGINEERING JOURNAL
(2022)
Article
Engineering, Multidisciplinary
Xiangming Zhang, Zhihua Liu
Summary: In this study, a predator-prey model with predator-age structure and predator-prey reaction time delay was investigated. By employing theoretical analysis and numerical simulations, the research identified the emergence of periodic oscillations under certain parameter values and examined the influence of different parameter values on the dynamic behavior of the system.
APPLIED MATHEMATICAL MODELLING
(2021)
Article
Mathematics
Ruizhi Yang, Xiao Zhao, Yong An
Summary: In this study, a delayed predator-prey model with diffusion and anti-predator behavior is investigated. The stability of the positive equilibrium is analyzed, and the existence of Hopf bifurcation is discussed based on the Hopf bifurcation theory. The properties of Hopf bifurcation are derived using the theory of center manifold and normal form method. Finally, the impact of time delay on the model is examined through numerical simulations.
Article
Engineering, Mechanical
Ruizhi Yang, Chenxuan Nie, Dan Jin
Summary: This paper investigates a delayed diffusive predator-prey model with nonlocal competition and habitat complexity. The local stability of coexisting equilibrium is studied by analyzing the eigenvalue spectrum. Time delay inducing Hopf bifurcation is explored using time delay as a bifurcation parameter. Conditions for determining the bifurcation direction and stability of the bifurcating periodic solution are derived using the normal form method and center manifold theorem. The results suggest that only the combination of nonlocal competition and diffusion can induce stably spatial inhomogeneous bifurcating periodic solutions.
NONLINEAR DYNAMICS
(2022)
Article
Mathematics
Qi Quan, Xiangjun Dai, Jianjun Jiao
Summary: This paper proposes a predator-prey model with impulsive diffusion and transient/nontransient impulsive harvesting. The stability and persistence of the model under simultaneous harvesting of predators and prey are investigated.
Article
Mathematics
Yining Xie, Jing Zhao, Ruizhi Yang
Summary: This paper proposes a diffusive predator-prey model with a strong Allee effect and nonlocal competition in the prey and a fear effect and gestation delay in the predator. The study mainly focuses on the local stability of the coexisting equilibrium and the existence and properties of Hopf bifurcation. Bifurcation diagrams with the fear effect parameter (s) and the Allee effect parameter (a) are provided, showing that the stable region of the coexisting equilibrium increases (or decreases) with an increase in the fear effect parameter (s) (or the Allee effect parameter (a)). The results demonstrate that the fear effect parameter (s), the Allee effect parameter (a), and gestation delay (t) can be utilized to control the growth of prey and predator populations.
Article
Engineering, Industrial
Jianxin Chen, Tonghua Zhang, Yong-wu Zhou, Rui Hou
Summary: This study investigates the ordering strategy of a risk-averse retailer under buyback guarantee financing (BGF) and stochastic demand using single-period and multi-period models in the newsvendor framework. It is found that the optimal ordering quantity is influenced by various parameters, and the multi-period model exhibits more complex dynamic behavior compared to the single-period model.
INTERNATIONAL JOURNAL OF PRODUCTION RESEARCH
(2022)
Article
Mathematics, Applied
Haokun Qi, Xinzhu Meng, Tasawar Hayat, Aatef Hobiny
Summary: This paper proposes a stochastic predator-prey model with hunting cooperation and nonlinear perturbation of white noise. Sufficient criteria for the existence of a unique ergodic stationary distribution are established by constructing suitable Lyapunov functions. It is revealed that the white noise significantly impacts the dynamical behavior of the model.
APPLIED MATHEMATICS LETTERS
(2022)
Article
Surgery
Yun-Liang Xie, Zhou Yang, Xiao Feng, Qing Yang, Lin-Sen Ye, Xiao-Bin Li, Hui Tang, Ying-Cai Zhang, Wei Liu, Tong Zhang, Bin-Sheng Fu, Shu-Hong Yi, Yang Yang, Gui-Hua Chen
Summary: This study analyzed CTCs in 56 patients using the CanPatrolTM platform combined with RNA-ISH, revealing the significance of interstitial CTCs in predicting post-transplant tumor recurrence among HCC patients.
ASIAN JOURNAL OF SURGERY
(2022)
Article
Biology
Guohao Shen, Kani Chen, Jian Huang, Yuanyuan Lin
Summary: In this paper, a linearized maximum rank correlation estimator is proposed for the single-index model. The estimator has a closed-form expression and is robust to outliers in the response. It does not require knowledge of the unknown link function or the error distribution. Extensive simulation studies and an application example demonstrate the effectiveness of the proposed method.
Article
Crystallography
Tong Zhang, Tong Li, Jinlin Lu, Qi Guo, Jian Xu
Summary: The clogging behavior of micro-orifices under a flow accelerated condition was studied after 500 h of immersion in high-temperature water. The results showed that the residual area of the micro-orifice decreased to one-third of its original size due to the deposition of corrosion products. The clogging process can be divided into three stages: stable deposition, quick recovery, and dynamic equilibrium. The corrosion products were porous and composed of multiple deposited particles.
Article
Chemistry, Physical
Lu Ren, Shicheng Wang, Jian Xu, Tong Zhang, Qi Guo, Dongyang Zhang, Jiajia Si, Xiaohui Zhang, Hongying Yu, Tetsuo Shoji, Dongbai Sun
Summary: The fouling in the steam generator has a significant impact on the internal integrity, heat transfer efficiency, and water chemistry control. The growth direction of fouling particles is influenced by the oxide layer. The nucleation, aggregation, adsorption, and growth of oxides are significantly affected by fouling deposition, which may have opposing impacts on the reliability of steam generator tubes.
APPLIED SURFACE SCIENCE
(2022)
Article
Engineering, Electrical & Electronic
Tong Zhang, Gaojie Chen, Rui Wang
Summary: This paper investigates the sum-secure degrees-of-freedom of a three-user MIMO broadcast channel with delayed CSIT and confidential messages. Non-trivial upper and lower bounds for the sum-secure degrees-of-freedom are derived using statistical equivalence property, security constraints, and permutations. Two transmission schemes with holistic and sequential higher-order symbol generation are proposed, along with a redundancy reduction approach for security analysis. The proposed bounds are tighter than existing ones and the lower bound showcases a three-user coding gain.
IEEE TRANSACTIONS ON VEHICULAR TECHNOLOGY
(2023)
Article
Chemistry, Multidisciplinary
Tongpo Zhang, Yunze Song, Zejian Kong, Tiantian Guo, Miguel Lopez-Benitez, Enggee Lim, Fei Ma, Limin Yu
Summary: This paper discusses the challenges of robot tracking under partial occlusion and compares the system performance of three recent DL models. A series of experiments are conducted to analyze the performance metrics under different scenarios and settings. Based on the metrics, a comparative metric P is devised to further compare the overall performance of the three DL models. The SSD model achieved the highest P score, outperforming the Faster RCNN and YOLOv5 models in both testing data sets.
APPLIED SCIENCES-BASEL
(2023)
Article
Oncology
Gang Deng, Jun-kai Ren, Hai-tao Wang, Liang Deng, Zu-bing Chen, You-wen Fan, Ya-jun Tang, Tong Zhang, Di Tang
Summary: This study found that the tumor burden score (TBS) has prognostic value in patients with combined hepatocellular-cholangiocarcinoma (cHCC-CCA). TBS is associated with long-term outcomes, with high TBS being related to poorer disease-free survival (DFS) and overall survival (OS), and it is identified as an independent prognostic indicator.
FRONTIERS IN ONCOLOGY
(2023)
Article
Mathematics, Applied
Yu Yang, Tonghua Zhang, Jinling Zhou
Summary: This paper investigates the global stability of disease-free steady state for a degenerate reaction-diffusion host-pathogen model with spatial heterogeneity when R0 = 1. The study is a continuation of the work by Wang and Dai (2022).
APPLIED MATHEMATICS LETTERS
(2023)
Article
Mathematics, Interdisciplinary Applications
Jianxin Chen, Rui Hou, Lu Xiao, Tonghua Zhang, Yongwu Zhou
Summary: Considering corporate social responsibility, this paper examines the equilibrium strategies of a closed-loop supply chain consisting of a manufacturer, a fairness-concerned retailer, and a capital-constrained recycler in both static and dynamic frameworks. The study incorporates supply chain financing and fairness concerns and explores the complex dynamics and impacts of parameters on decision-making and system stability.
CHAOS SOLITONS & FRACTALS
(2023)
Article
Mathematics, Interdisciplinary Applications
Tongqian Zhang, Xinna Xu, Xinzeng Wang
Summary: In this paper, a cytokine-enhanced viral infection model with time delays and CTL immune response is proposed and analyzed. The stability of equilibria of the model is investigated by constructing suitable Lyapunov functionals and using LaSalle's invariance principle. The system produces periodic oscillation under certain conditions.
CHAOS SOLITONS & FRACTALS
(2023)
Proceedings Paper
Computer Science, Artificial Intelligence
Han Zhong, Wei Xiong, Jiyuan Tan, Liwei Wang, Tong Zhang, Zhaoran Wang, Zhuoran Yang
Summary: This paper studies offline two-player zero-sum Markov games (MGs) and proposes a pessimism-based algorithm called pessimistic minimax value iteration (PMVI) to overcome the challenges in finding an approximate Nash equilibrium. The paper also establishes a data-dependent upper bound and proves an information-theoretical lower bound, showing that the proposed algorithm is nearly minimax optimal. The results highlight the importance of relative uncertainty in achieving sample efficiency in offline MGs.
INTERNATIONAL CONFERENCE ON MACHINE LEARNING, VOL 162
(2022)
Proceedings Paper
Computer Science, Artificial Intelligence
Xiao Zhou, Yong Lin, Weizhong Zhang, Tong Zhang
Summary: Invariant Risk Minimization (IRM) is an emerging technique for addressing generalization issues caused by distributional shift. However, there is a contradiction between model trainability and generalization ability in IRM, as overfitting caused by overparameterization can harm its generalization ability. To tackle this problem, this paper proposes Sparse Invariant Risk Minimization (SparseIRM) which employs a global sparsity constraint to select invariant features and prevent spurious features from leaking in. Theoretical analysis and empirical results demonstrate the effectiveness of SparseIRM.
INTERNATIONAL CONFERENCE ON MACHINE LEARNING, VOL 162
(2022)
Article
Biochemical Research Methods
Chengxian Li, Haihong Liu, Tonghua Zhang, Yuan Zhang
Summary: This paper investigates a model of miR-9/Hes1 interaction network with time delay and diffusion effect. The stability of the positive equilibrium and the existence of local Hopf bifurcation and Turing-Hopf bifurcation are analyzed. An algorithm for determining the direction, stability, and period of the corresponding bifurcating periodic solutions is presented. The results show that time delay can induce oscillation in quiescent progenitors but has little effect on the differentiated state. The integrated effect of delay and diffusion can lead to spatially inhomogeneous patterns. Moreover, spatially homogeneous/inhomogeneous periodic solutions can coexist when the diffusion coefficients are appropriately small.
IEEE-ACM TRANSACTIONS ON COMPUTATIONAL BIOLOGY AND BIOINFORMATICS
(2022)
