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Bifurcationing Analysis of Predator-Prey Diffusive System Based on Bazykin Functional Response
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作者 Mingyang Zhao Fuqin Sun 《Journal of Applied Mathematics and Physics》 2022年第12期3836-3842,共7页
A predator-prey diffusion system with a Bazykin functional response is studied. The existence of equilibrium points, the stability of normal number equilibrium points and the existence of Hopf bifurcationes are invest... A predator-prey diffusion system with a Bazykin functional response is studied. The existence of equilibrium points, the stability of normal number equilibrium points and the existence of Hopf bifurcationes are investigated for the proposed system, the existence of positive solutions in the system is discussed under Neumann boundary conditions, and the stability of constant equilibrium points is focused on under the condition of Hurwitz criterion. The results show that there exist positive equilibrium points in the system under Neumann boundary conditions, and the normal number equilibrium points are stable when specific conditions are satisfied, and the bifurcation points of Hopf bifurcationes and their orders are given. 展开更多
关键词 Bazykin Functional Response diffusion System EXISTENCE STABILITY Hopf Bifurcation
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Note on a diffusive ratio-dependent predator-prey model
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作者 陈滨 许志奋 《Journal of Southeast University(English Edition)》 EI CAS 2006年第2期294-296,共3页
Subject to the homogeneous Neumann boundary condition, a ratio-dependent predator-prey reaction diffusion model is discussed. An improved result for the model is derived, that is, the unique positive constant steady s... Subject to the homogeneous Neumann boundary condition, a ratio-dependent predator-prey reaction diffusion model is discussed. An improved result for the model is derived, that is, the unique positive constant steady state is the global stability. This is done using the comparison principle and establishing iteration schemes involving positive solutions supremum and infimum. The result indicates that the two species will ultimately distribute homogeneously in space. In fact, the comparison argument and iteration technique to be used in this paper can be applied to some other models. This method deals with the not-existence of a non-constant positive steady state for some reaction diffusion systems, which is rather simple but sufficiently effective. 展开更多
关键词 ratio-dependent predator-prey model global stability comparison principle ITERATION
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INVASION TRAVELING WAVES FOR A DISCRETE DIFFUSIVE RATIO-DEPENDENT PREDATOR-PREY MODEL 被引量:1
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作者 Tao SU Guobao ZHANG 《Acta Mathematica Scientia》 SCIE CSCD 2020年第5期1459-1476,共18页
This article is concerned with the existence of traveling wave solutions for a discrete diffusive ratio-dependent predator-prey model. By applying Schauder’s fixed point theorem with the help of suitable upper and lo... This article is concerned with the existence of traveling wave solutions for a discrete diffusive ratio-dependent predator-prey model. By applying Schauder’s fixed point theorem with the help of suitable upper and lower solutions, we prove that there exists a positive constant c* such that when c > c* , the discrete diffusive predator-prey system admits an invasion traveling wave. The existence of an invasion traveling wave with c = c* is also established by a limiting argument and a delicate analysis of the boundary conditions.Finally, by the asymptotic spreading theory and the comparison principle, the non-existence of invasion traveling waves with speed c < c* is also proved. 展开更多
关键词 predator-prey system ratio-dependent functional response discrete diffusion invasion traveling waves
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Periodic Solution for Diffusive Predator-Prey System with Functional Response 被引量:4
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作者 Li Bi\|wen 1,2 , Cheng Jian 1 1. Department of Mathematics, Hubei Normal University, Huangshi 435002, Hubei,China 2. School of Mathematics and Statistics, Wuhan University, Wuhan 430072, Hubei,China 《Wuhan University Journal of Natural Sciences》 CAS 2002年第3期267-273,共7页
In this paper, a three species diffusive predator-prey model with functional response is studied, where all parameters are time dependent. By using the continuation theorem of coincidence degree theory, the existence ... In this paper, a three species diffusive predator-prey model with functional response is studied, where all parameters are time dependent. By using the continuation theorem of coincidence degree theory, the existence of a positive periodic solution for this system is established. 展开更多
关键词 diffusive model functional nesponse positive periodic solution continuation theorem of coincidence degree fopological degree
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POSITIVE STEADY STATES OF A DIFFUSIVE PREDATOR-PREY SYSTEM WITH PREDATOR CANNIBALISM 被引量:3
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作者 王彪 《Acta Mathematica Scientia》 SCIE CSCD 2017年第5期1385-1398,共14页
The purpose of this paper is to investigate positive steady states of a diffusive predator-prey system with predator cannibalism under homogeneous Neumann boundary conditions. With the help of implicit function theore... The purpose of this paper is to investigate positive steady states of a diffusive predator-prey system with predator cannibalism under homogeneous Neumann boundary conditions. With the help of implicit function theorem and energy integral method, nonexistence of non-constant positive steady states of the system is obtained, whereas coexistence of non-constant positive steady states is derived from topological degree theory. The results indicate that if dispersal rate of the predator or prey is sufficiently large, there is no nonconstant positive steady states. However, under some appropriate hypotheses, if the dispersal rate of the predator is larger than some positive constant, for certain ranges of dispersal rates of the prey, there exists at least one non-constant positive steady state. 展开更多
关键词 predator-prey existence and nonexistence pattern formation
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Global Asymptotic Stability and Hopf Bifurcation in a Homogeneous Diffusive Predator-Prey System with Holling Type II Functional Response 被引量:3
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作者 Shuangte Wang Hengguo Yu +1 位作者 Chuanjun Dai Min Zhao 《Applied Mathematics》 2020年第5期389-406,共18页
In this paper, we considered a homogeneous reaction-diffusion predator-prey system with Holling type II functional response subject to Neumann boundary conditions. Some new sufficient conditions were analytically esta... In this paper, we considered a homogeneous reaction-diffusion predator-prey system with Holling type II functional response subject to Neumann boundary conditions. Some new sufficient conditions were analytically established to ensure that this system has globally asymptotically stable equilibria and Hopf bifurcation surrounding interior equilibrium. In the analysis of Hopf bifurcation, based on the phenomenon of Turing instability and well-done conditions, the system undergoes a Hopf bifurcation and an example incorporating with numerical simulations to support the existence of Hopf bifurcation is presented. We also derived a useful algorithm for determining direction of Hopf bifurcation and stability of bifurcating periodic solutions correspond to j &#8800;0 and j = 0, respectively. Finally, all these theoretical results are expected to be useful in the future study of dynamical complexity of ecological environment. 展开更多
关键词 HOLLING Type II Functional Response REACTION-diffusION predator-prey System Global Stability TURING Instability Hopf Bifurcation
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POSITIVE STEADY STATES AND DYNAMICS FOR A DIFFUSIVE PREDATOR-PREY SYSTEM WITH A DEGENERACY 被引量:2
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作者 杨璐 张贻民 《Acta Mathematica Scientia》 SCIE CSCD 2016年第2期537-548,共12页
In this article, we consider positive steady state solutions and dynamics for a spatially heterogeneous predator-prey system with modified Leslie-Gower and Holling-Type II schemes. The heterogeneity here is created by... In this article, we consider positive steady state solutions and dynamics for a spatially heterogeneous predator-prey system with modified Leslie-Gower and Holling-Type II schemes. The heterogeneity here is created by the degeneracy of the intra-specific pressures for the prey. By the bifurcation method, the degree theory, and a priori estimates, we discuss the existence and multiplicity of positive steady states. Moreover, by the comparison argument, we also discuss the dynamical behavior for the diffusive predator-prey system. 展开更多
关键词 predator-prey system steady state solution dynamical behavior
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Diffusive Transfer between a Droplet and an Immiscible Oscillating Liquid in a Radial Hele-Shaw Cell
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作者 Ivan Karpunin Denis Polezhaev 《Fluid Dynamics & Materials Processing》 2025年第3期543-553,共11页
An experimental study of the diffusive mass transfer between a droplet and an oscillating immiscible liquid in a horizontal axisymmetricHele-Shaw cell is carried out.Theliquid oscillates radially in the cell.Thetransv... An experimental study of the diffusive mass transfer between a droplet and an oscillating immiscible liquid in a horizontal axisymmetricHele-Shaw cell is carried out.Theliquid oscillates radially in the cell.Thetransverse size of the droplet exceeds the cell thickness.The viscosities of the droplet and the surrounding liquid are comparable.Relevant effort is provided to design and test an experimental setup and validate a protocol for determining the mass transfer rate of a solute in a two-liquid system.In particular,fluorescent dye Rhodamine B is considered as the solute.A critical comparison of the situations with and without oscillation is implemented.A procedure is introduced and validated to determine the molecular and effective diffusion coefficients through evaluation of the growth of the diffusion zone width over time.It is shown that,in the presence of the liquid oscillations,there is a significant increase in the width of the zone in which Rhodamine B is present compared to the reference case with no oscillations.The oscillatory flow leads to an intensification of the solute diffusion due to intense time-averaged flows inside the droplet and the surrounding liquid and oscillations of the drop itself.Thestudy is of significant practical interest with particular relevance to typical processes for liquid-liquid extraction. 展开更多
关键词 OSCILLATIONS DROPLET VISCOSITY diffusion Rhodamine B fluorescence radial Hele-Shaw cell
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Emulation of short-term and long-term synaptic plasticity with high uniformity in chalcogenide-based diffusive memristor device for neuromorphic applications
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作者 Haider Abbas Jiayi Li +3 位作者 Asif Ali Sajjad Hussain Jongwan Jung Diing Shenp Ang 《Journal of Materials Science & Technology》 2025年第13期99-107,共9页
Emerging bio-inspired computing systems simulate the cognitive functions of the brain for the realiza-tion of future computing systems.For the development of such efficient neuromorphic electronics,the emulation of sh... Emerging bio-inspired computing systems simulate the cognitive functions of the brain for the realiza-tion of future computing systems.For the development of such efficient neuromorphic electronics,the emulation of short-term and long-term synaptic plasticity behaviors of the biological synapses is an es-sential step.However,the electronic synaptic devices suffer from higher variability issues which hinder the application of such devices to build neuromorphic systems.For practical applications,it is essen-tial to minimize the cycle-to-cycle and device-to-device variations in the synaptic functions of artifi-cial electronic synapses.This study involves the fabrication of diffusive memristor devices using WTe_(2) chalcogenide as the main switching material.The choice of the switching material provides a facile so-lution to the variability problem.The greater uniformity in the switching characteristics of the WTe_(2)-based memristor offers higher uniformity for the synaptic emulation.These devices exhibit both volatile and nonvolatile switching properties,allowing them to emulate both short-term and long-term synaptic functions.The WTe_(2)-based electronic synaptic devices present a high degree of uniformity for the emula-tion of various essential biological synaptic functions including short-term potentiation(STP),long-term potentiation(LTP),long-term depression(LTD),spike-rate-dependent plasticity(SRDP),and spike-timing-dependent plasticity(STDP).A higher recognition accuracy of∼92%is attained for pattern recognition using the modified National Institute of Standards and Technology(MNIST)handwritten digits,which is attributed to the enhanced linearity and higher uniformity of LTP/LTD characteristics. 展开更多
关键词 diffusive memristor Chalcogenide switching layer WTe_(2) UNIFORMITY Neuromorphic computing
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Quantification of the Kinetics of Soil Selenium Diffusive Gradients in Thin-Films Process under Long-Term Moisture Changes
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作者 Yu Zhang Xinghan Wang +4 位作者 Yanan Liu Yankui Chen Luxuan Zhang Yuxin Zhang Yu Zhang 《Journal of Environmental & Earth Sciences》 2025年第4期266-279,共14页
The effects of long-term moisture changes on the migration,release,and bioavailability of selenium in soil are complex.Due to the lack of effective monitoring methods for precise quantification,its dynamic behavior is... The effects of long-term moisture changes on the migration,release,and bioavailability of selenium in soil are complex.Due to the lack of effective monitoring methods for precise quantification,its dynamic behavior is still unclear.Based on the DGT(Diffusive Gradients in Thin-films)technology,this study sets up three moisture control scenarios:continuous wet,wet-dry alternating,and continuous dry,and carries out a 6-month soil moisture control experiment.In the experiment,the DGT device collected the diffusion gradient data of soil selenium under different scenarios,and analyzed the migration characteristics of selenium in combination with the adsorption isotherm.Meanwhile,the release rate,migration coefficient,and bioavailability parameters of selenium are calculated by fitting the first-order kinetic model,further verifying the reliability and applicability of the DGT data.The experimental results demonstrate that under continuous wet conditions,the release rate of soil selenium reaches 1.85µg·cm^(-2)·h^(-1),with a migration coefficient of 0.012 cm^(2)·h^(-1)and a bioavailability parameter of 0.74;under wet-dry alternating conditions,they are 1.42µg·cm^(-2)·h^(-1),0.01 cm^(2)·h^(-1),and 0.68,respectively;under continuous dry conditions,the release rate of soil selenium is the smallest,at 0.88µg·cm^(-2)·h^(-1),with a migration coefficient of 0.004 cm^(-2)·h^(-1)and a bioavailability parameter of 0.5.The results of this experiment reveal the dynamic behavior of soil selenium under different moisture conditions and reflect the high efficiency of DGT technology in dynamic monitoring and quantitative analysis of soil selenium behavior,providing a scientific basis for the optimal management of rhizosphere soil selenium. 展开更多
关键词 Soil Selenium Dynamics Moisture Regulation Effects diffusive Gradients in Thin-Films Selenium Bioavail-ability Analysis Kinetic Analysis
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Motion In-Betweening via Frequency-Domain Diffusion Model
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作者 Qiang Zhang Shuo Feng +2 位作者 Shanxiong Chen Teng Wan Ying Qi 《Computers, Materials & Continua》 2026年第1期275-296,共22页
Human motion modeling is a core technology in computer animation,game development,and humancomputer interaction.In particular,generating natural and coherent in-between motion using only the initial and terminal frame... Human motion modeling is a core technology in computer animation,game development,and humancomputer interaction.In particular,generating natural and coherent in-between motion using only the initial and terminal frames remains a fundamental yet unresolved challenge.Existing methods typically rely on dense keyframe inputs or complex prior structures,making it difficult to balance motion quality and plausibility under conditions such as sparse constraints,long-term dependencies,and diverse motion styles.To address this,we propose a motion generation framework based on a frequency-domain diffusion model,which aims to better model complex motion distributions and enhance generation stability under sparse conditions.Our method maps motion sequences to the frequency domain via the Discrete Cosine Transform(DCT),enabling more effective modeling of low-frequency motion structures while suppressing high-frequency noise.A denoising network based on self-attention is introduced to capture long-range temporal dependencies and improve global structural awareness.Additionally,a multi-objective loss function is employed to jointly optimize motion smoothness,pose diversity,and anatomical consistency,enhancing the realism and physical plausibility of the generated sequences.Comparative experiments on the Human3.6M and LaFAN1 datasets demonstrate that our method outperforms state-of-the-art approaches across multiple performance metrics,showing stronger capabilities in generating intermediate motion frames.This research offers a new perspective and methodology for human motion generation and holds promise for applications in character animation,game development,and virtual interaction. 展开更多
关键词 Motion generation diffusion model frequency domain human motion synthesis self-attention network 3D motion interpolation
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Visual prognosis and survival outcomes in patients with ocular adnexal diffuse large B-cell lymphoma
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作者 Sirawit Wainipitapong Orapan Aryasit +1 位作者 Panarat Noiperm Mansing Ratanasukon 《International Journal of Ophthalmology(English edition)》 2026年第2期354-361,共8页
AIM:To investigate the clinical characteristics and treatment outcomes,including visual function and overall survival(OS)of patients with ocular adnexal diffuse large B-cell lymphoma(OA-DLBCL).METHODS:This retrospecti... AIM:To investigate the clinical characteristics and treatment outcomes,including visual function and overall survival(OS)of patients with ocular adnexal diffuse large B-cell lymphoma(OA-DLBCL).METHODS:This retrospective cohort study enrolled 29 patients diagnosed with OA-DLBCL based on histopathological biopsy between 2006 and 2023.Patients were stratified into two subgroups:primary OA-DLBCL(no prior history of lymphoma)and secondary OA-DLBCL(history of DLBCL at non-ocular adnexal sites).OS was defined as the time interval from OA-DLBCL diagnosis to death from any cause.Survival analysis was performed using the Kaplan–Meier method,and prognostic factors affecting OS were identified using multivariate Cox proportional hazards regression with a stepwise selection approach.RESULTS:The cohort included 24 patients with primary OA-DLBCL(13 males,11 females;mean age:61.36±18.29y)and 5 patients with secondary OA-DLBCL(2 males,3 females;mean age:50.94±18.17y).Among the primary OA-DLBCL subgroup,12 patients(50%)presented with advanced disease(Ann Arbor stage IIIE–IV),and 16 patients(66%)were classified as T4 disease according to the tumor-node-metastasis(TNM)staging system.The mean final visual acuity was 1.72±1.10 in the primary group and 0.90±1.18 in the secondary group.The 5-year OS rate for the entire cohort was 27.7%.Multivariate analysis identified five factors significantly associated with poor survival outcomes:epiphora[adjusted hazard ratio(aHR),36.95],atherosclerotic cardiovascular disease(aHR,10.08),human immunodeficiency virus(HIV)infection(aHR,12.47),M1 stage(aHR,6.99),and secondary OA-DLBCL(aHR,6.03;all P<0.05).The median OS was 1.68y for primary OA-DLBCL and 1.12y for secondary OA-DLBCL.CONCLUSION:A substantial proportion of patients with primary OA-DLBCL present with advanced-stage disease at diagnosis.Epiphora,atherosclerotic cardiovascular disease,HIV infection,M1 stage,and secondary OA-DLBCL are independent prognostic factors for poor survival outcomes.These findings emphasize the urgent need for optimized therapeutic strategies and early screening protocols to improve the management of OA-DLBCL,particularly in developing countries. 展开更多
关键词 ocular adnexal diffuse large B-cell lymphoma visual prognosis overall survival prognostic factors Ann Arbor staging tumor-node-metastasis staging
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Some factors controlling diffusive transportof potassium ion through clayey soils 被引量:3
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作者 杜延军 刘松玉 林重德 《Journal of Southeast University(English Edition)》 EI CAS 2006年第1期106-111,共6页
To investigate the potential use of two Japanese regional clayey soils, named Ariake clay and Akaboku soil, as soil barrier materials, a series of laboratory diffusion tests are presented. Using an available computer ... To investigate the potential use of two Japanese regional clayey soils, named Ariake clay and Akaboku soil, as soil barrier materials, a series of laboratory diffusion tests are presented. Using an available computer program Pollute V6.3, the effective diffusion coefficients of K^+ of the soils were back-calculated from the diffusion tests. It is found that the Ariake clay has a larger effective diffusion coefficient than the Akaboku soil, indicating that the Ariake clay may provide a better diffusion barrier. A comparison of the effective diffusion coefficients between the single-salt solution condition and the multi-salt solution condition indicates that soils have higher effective diffusion coefficients under the former condition. It is suggested to use miscible solution close to landfill leachates for determining effective diffusion coefficients of specified chemical species for a practical design. 展开更多
关键词 adsorption Ariake clay BARRIER batch-type test CONTAMINANT diffusion LANDFILL
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AI绘图助力三维设计发展——以Stable Diffusion为例 被引量:2
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作者 刘凇麟 杨蕾颖 《昆明冶金高等专科学校学报》 2025年第1期61-69,共9页
AI绘图工具是利用人工智能技术,通过本地部署训练辅助或完全自动生成绘画作品的软件工具。目前常用的AI绘图工具有DALL-E 2、Midjourney、Stable Diffusion等,其中以Stable Diffusion使用最为广泛。通过不断更新图像的噪声分布,软件在... AI绘图工具是利用人工智能技术,通过本地部署训练辅助或完全自动生成绘画作品的软件工具。目前常用的AI绘图工具有DALL-E 2、Midjourney、Stable Diffusion等,其中以Stable Diffusion使用最为广泛。通过不断更新图像的噪声分布,软件在本地计算机上生成高质量图像。以实际设计项目为例,应用Stable Diffusion在三维设计中帮助设计师快速生成草图和效果图,得到多种设计风格和创作方式,大大提高了设计的效率和乐趣,实践证明AI绘图工具在环境艺术设计、建筑设计等多个领域具有巨大的应用潜力。 展开更多
关键词 AI绘图 Stable diffusion 三维设计
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LogDiffusion:一种基于扩散概率模型的岩性识别方法 被引量:1
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作者 赵逢达 韩滋民 +2 位作者 付晓飞 章蓬伟 李贤善 《地球物理学进展》 北大核心 2025年第1期106-120,共15页
岩性识别是油气资源勘查开发过程中的关键步骤之一.目前,利用深度学习技术进行测井岩性识别能够显著提高识别速度和准确率,然而,由于测井数据集经常存在数据量不足和岩性类别分布不均衡等问题,神经网络在训练过程中容易出现过拟合现象,... 岩性识别是油气资源勘查开发过程中的关键步骤之一.目前,利用深度学习技术进行测井岩性识别能够显著提高识别速度和准确率,然而,由于测井数据集经常存在数据量不足和岩性类别分布不均衡等问题,神经网络在训练过程中容易出现过拟合现象,导致模型的准确率降低.为了解决这些问题,本文提出一种基于扩散概率模型的岩性识别模型LogDiffusion,该模型能够生成高质量的测井数据并用于训练,从而提升岩性识别的分类准确率.在传统的扩散概率模型的基础上,考虑到测井数据的一维结构,本文设计了一种用于估计梯度的分数网络FT-Unet,并提出了一种辅助分类器FT-Transformer以获取准确的岩性标签.此外,还提出了一种基于阈值的动态标签机制以提高采样算法的准确性.在两个小样本盲井测井数据集上的实验结果表明,该方法能够一定程度上解决测井数据集数据量不足和岩性类别分布不均衡的问题,从而提升岩性识别的准确率和精度. 展开更多
关键词 岩性识别 数据增强 深度学习 扩散概率模型
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ON A MULTI-DELAY LOTKA-VOLTERRA PREDATOR-PREY MODEL WITH FEEDBACK CONTROLS AND PREY DIFFUSION 被引量:3
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作者 Changyou WANG Nan LI +2 位作者 Yuqian ZHOU Xingcheng PU Rui LI 《Acta Mathematica Scientia》 SCIE CSCD 2019年第2期429-448,共20页
This article is focusing on a class of multi-delay predator-prey model with feedback controls and prey diffusion. By developing some new analysis methods and using the theory of differential inequalities as well as co... This article is focusing on a class of multi-delay predator-prey model with feedback controls and prey diffusion. By developing some new analysis methods and using the theory of differential inequalities as well as constructing a suitable Lyapunov function, we establish a set of easily verifiable sufficient conditions which guarantee the permanence of the system and the globally attractivity of positive solution for the predator-prey system.Furthermore, some conditions for the existence, uniqueness and stability of positive periodic solution for the corresponding periodic system are obtained by using the fixed point theory and some new analysis techniques. In additional, some numerical solutions of the equations describing the system are given to verify the obtained criteria are new, general, and easily verifiable. Finally, we still solve numerically the corresponding stochastic predator-prey models with multiplicative noise sources, and obtain some new interesting dynamical behaviors of the system. 展开更多
关键词 predator-prey model: delay diffusion: PERMANENCE ATTRACTIVITY periodic solution
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Nonlinear predator-prey singularly perturbed Robin Problems for reaction diffusion systems 被引量:4
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作者 莫嘉琪 韩祥临 《Journal of Zhejiang University Science》 CSCD 2003年第5期511-513,共3页
The nonlinear predator-prey reaction diffusion systems for singularly perturbed Robin Problems are considered. Under suitable conditions, the theory of differential inequalities can be used to study the asymptotic beh... The nonlinear predator-prey reaction diffusion systems for singularly perturbed Robin Problems are considered. Under suitable conditions, the theory of differential inequalities can be used to study the asymptotic behavior of the solution for initial boundary value problems. 展开更多
关键词 NONLINEAR predator-prey Reaction diffusion Singular perturbation
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NONLINEAR SINGULARLY PERTURBED PREDATOR-PREY REACTION DIFFUSION SYSTEMS 被引量:5
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作者 MoJiaqi TangRongrong 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2004年第1期57-66,共10页
A class of nonlinear predator prey reaction diffusion systems for singularly pe rturbed problems are considered.Under suitable conditions, by using theory of di fferential inequalities the existence and asymptotic be... A class of nonlinear predator prey reaction diffusion systems for singularly pe rturbed problems are considered.Under suitable conditions, by using theory of di fferential inequalities the existence and asymptotic behavior of solution for in itial boundary value problems are studied. 展开更多
关键词 NONLINEAR predator PREY reaction diffusion singular perturbation.
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Effect of Diffusively Shaped Holes on the Turbulent Flow Field of a Film Cooling Plate 被引量:3
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作者 施红辉 桐山贤司 伊藤基之 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2002年第1期6-11,共6页
The gas turbine blades with diffusion film cooling holes are newlydeveloped blade struc- tures in the hydrogen combustion gas turbine,which has an extremely high inlet gas temperature (1700 deg. C). TheFluid Machinery... The gas turbine blades with diffusion film cooling holes are newlydeveloped blade struc- tures in the hydrogen combustion gas turbine,which has an extremely high inlet gas temperature (1700 deg. C). TheFluid Machinery Laboratory of Nagoya Institute o Technology conductedfirstly a new research o the turbulent flow field over the gasturbine blade with diffusion film cooling holes in Japan. Normal-typeand X-ray hot wires were applied in the measurement of the flowfield. 展开更多
关键词 turbulent boundary layer film cooling diffusion hole hot wireanemometry
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Observational analysis of the double-diffusive convection in the deep Canada Basin 被引量:2
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作者 XIE Lingling LI Mingming LI Min 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2015年第11期71-79,共9页
The Canada Basin (CB) is the largest sub-basin in the Arctic, with the deepest abyssal plain of 3 850 m. The double-diffusive process is the possible passage through which the geothermal energy affects the above iso... The Canada Basin (CB) is the largest sub-basin in the Arctic, with the deepest abyssal plain of 3 850 m. The double-diffusive process is the possible passage through which the geothermal energy affects the above isolated deep waters. With the temperature-salinity-pressure observations in 2003, 500-m-thick transition layers and lower 1 000-m-thick bottom homogenous layers were found below 2 400 m in the central deep CB. Staircases with downward-increasing temperature and salinity are prominent in the transition layers, suggesting the double- diffusive convection in deep CB. The interface of the stairs is about 10 m thick with 0.001-0.002℃ temperature difference, while the thicknesses of the homogenous layers in the steps decrease upward from about 60 to 20 m. The density ratio in the deep central CB is generally smaller than 2, indicating stronger double-diffusive convection than that in the upper ocean of 200-400 m. The heat flux through the deepest staircases in the deep CB varies between 0.014 and 0.031 W/m2, which is one-two orders smaller than the upper double-diffusive heat flux, but comparable to the estimates of geothermal heat flux. 展开更多
关键词 double diffusion Canada Basin STAIRCASE heat flux water mass
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