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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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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 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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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 WTe2 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 WTe2-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 WTe2-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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Patterned Solutions of a Homogenous Diffusive Predator-Prey System of Holling Type-Ⅲ 被引量:1
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作者 A-ying WAN Zhi-qiang SONG Li-fei ZHENG 《Acta Mathematicae Applicatae Sinica》 SCIE CSCD 2016年第4期1073-1086,共14页
In this paper, a diffusive predator-prey system of Holling type functional III is considered. For one hand, we considered the possibility of the occurrence of Turing patterns of the system. Our results show that there... In this paper, a diffusive predator-prey system of Holling type functional III is considered. For one hand, we considered the possibility of the occurrence of Turing patterns of the system. Our results show that there is no Turing patterns found in the system. On the other hand, we performed detailed Hopf bifurcation analysis to the systems, and showed that the system have multiple oscillatory patterns. Moreover, we also derived the conditions to determine the Hopf bifurcation direction and the stability of the bifurcating periodic solutions. Computer simulations are included to support our theoretical analysis. 展开更多
关键词 diffusive predator-prey system Hholling type functional response Hopf bifurcation turing insta-bility.
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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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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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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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Stable Diffusion在设计类专业教学中的应用——以三维设计软件应用课程为例
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作者 刘凇麟 杨蕾颖 +2 位作者 危威 李健僖 张馨 《昆明冶金高等专科学校学报》 2025年第4期119-124,共6页
随着人工智能技术的快速发展,Stable Diffusion作为一种先进的图像生成和扩散模型,在设计领域中显现出巨大的应用潜力。通过Stable Diffusion在三维设计软件应用课程中的具体应用案例,结合课程目标和内容,分析其在提升教学质量、激发学... 随着人工智能技术的快速发展,Stable Diffusion作为一种先进的图像生成和扩散模型,在设计领域中显现出巨大的应用潜力。通过Stable Diffusion在三维设计软件应用课程中的具体应用案例,结合课程目标和内容,分析其在提升教学质量、激发学生创意和拓展设计思维方面的作用,符合当今教育和技术发展的趋势。通过实际教学,证明AI融入教学,能够有效提高学生学习兴趣和参与度、增强设计作品多样性和创新性;同时,对传统设计类教学也提出了挑战。提出了新的教学内容和应用建议,为艺术设计教育的发展提供了新的思路和方法。 展开更多
关键词 Stablediffusion模型 设计类专业 教学
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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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生成式AI在建筑设计中的应用难点及优化策略:以Stable Diffusion为例 被引量:2
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作者 胡旭明 季新亮 周振阳 《世界建筑》 2025年第6期83-89,共7页
随着人工智能在工程设计领域应用的逐渐深入,AI开始介入设计、优化、建造运维等工程全生命周期,尤其是生成式AI,其在设计中的应用场景逐步被挖掘,带来了设计范式的新变革,引发了设计行业的广泛讨论与应用探索。与此同时,生成式AI在工程... 随着人工智能在工程设计领域应用的逐渐深入,AI开始介入设计、优化、建造运维等工程全生命周期,尤其是生成式AI,其在设计中的应用场景逐步被挖掘,带来了设计范式的新变革,引发了设计行业的广泛讨论与应用探索。与此同时,生成式AI在工程设计中的应用难点也逐步显现:垂直领域模型训练量不足、缺乏对参数之间交互影响的认识、未构建精准提示词工程等问题制约了其在行业的深度应用和价值呈现。本研究以Stable Diffusion为例分析其在建筑设计中的应用难点及成因,针对性提出优化方法,并通过项目实践验证了其有效性,从而实现生成式AI在多种建筑设计场景下的高质量可控输出。 展开更多
关键词 AI 生成式AI Stable diffusion 建筑设计 优化策略
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A diffusive predator-prey system with additional food and intra-specific competition among predators 被引量:1
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作者 Ruizhi Yang Ming Liu Chunrui Zhangt 《International Journal of Biomathematics》 SCIE 2018年第4期301-328,共28页
In this paper, a diffusive predator-prey system with additional food and intra-specific competition among predators subject to Neumann boundary condition is investigated. For non-delay system, global stability, Turing... In this paper, a diffusive predator-prey system with additional food and intra-specific competition among predators subject to Neumann boundary condition is investigated. For non-delay system, global stability, Turing instability and Hopf bifurcation are studied. For delay system, instability and Hopf bifurcation induced by time delay and global stability of boundary equilibrium are discussed. By the theory of normal form and center manifold method, the conditions for determining the bifurcation direction and the stability of the bifurcating periodic solution are derived. 展开更多
关键词 predator-prey additional food DELAY Turing instability Hopf bifurcation.
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人工智能在绘画领域的应用——以Stable Diffusion搭配ControlNet为例 被引量:1
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作者 叶雨杭 雷雅琴 《科学与信息化》 2025年第2期60-63,共4页
文章分析了Stable Diffusion的技术原理与插件ControlNet的功能,以及两者结合之后出图的效果及优势和劣势。同时分析如何通过ComfyUI添加插件搭建工作流,以提升工作效率,减少工作时间。本文旨在通过应用人工智能技术将设计师从单一的重... 文章分析了Stable Diffusion的技术原理与插件ControlNet的功能,以及两者结合之后出图的效果及优势和劣势。同时分析如何通过ComfyUI添加插件搭建工作流,以提升工作效率,减少工作时间。本文旨在通过应用人工智能技术将设计师从单一的重复的工作中解放出来,专注于设计本身而不是设计绘画的过程,让数字绘画技术赋予绘画领域升级。 展开更多
关键词 AIGC 人工智能 数字绘画 平面设计 Stable diffusion CONTROLNET
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Mechanism of Thermally Radiative Prandtl Nanofluids and Double-Diffusive Convection in Tapered Channel on Peristaltic Flow with Viscous Dissipation and Induced Magnetic Field
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作者 Yasir Khan Safia Akram +3 位作者 Maria Athar Khalid Saeed Alia Razia A.Alameer 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第2期1501-1520,共20页
The application of mathematical modeling to biological fluids is of utmost importance, as it has diverse applicationsin medicine. The peristaltic mechanism plays a crucial role in understanding numerous biological flo... The application of mathematical modeling to biological fluids is of utmost importance, as it has diverse applicationsin medicine. The peristaltic mechanism plays a crucial role in understanding numerous biological flows. In thispaper, we present a theoretical investigation of the double diffusion convection in the peristaltic transport of aPrandtl nanofluid through an asymmetric tapered channel under the combined action of thermal radiation andan induced magnetic field. The equations for the current flow scenario are developed, incorporating relevantassumptions, and considering the effect of viscous dissipation. The impact of thermal radiation and doublediffusion on public health is of particular interest. For instance, infrared radiation techniques have been used totreat various skin-related diseases and can also be employed as a measure of thermotherapy for some bones toenhance blood circulation, with radiation increasing blood flow by approximately 80%. To solve the governingequations, we employ a numerical method with the aid of symbolic software such as Mathematica and MATLAB.The velocity, magnetic force function, pressure rise, temperature, solute (species) concentration, and nanoparticlevolume fraction profiles are analytically derived and graphically displayed. The results outcomes are compared withthe findings of limiting situations for verification. 展开更多
关键词 Double diffusion convection thermal radiation induced magnetic field peristaltic flow tapered asymmetric channel viscous dissipation Prandtl nanofluid
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Medical Image Encryption Based on Fisher-Yates Scrambling and Filter Diffusion 被引量:1
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作者 HUANG Jiacin GUO Yali +1 位作者 GAO Ruoyun LI Shanshan 《Journal of Shanghai Jiaotong university(Science)》 2025年第1期136-152,共17页
A medical image encryption is proposed based on the Fisher-Yates scrambling,filter diffusion and S-box substitution.First,chaotic sequence associated with the plaintext is generated by logistic-sine-cosine system,whic... A medical image encryption is proposed based on the Fisher-Yates scrambling,filter diffusion and S-box substitution.First,chaotic sequence associated with the plaintext is generated by logistic-sine-cosine system,which is used for the scrambling,substitution and diffusion processes.The three-dimensional Fisher-Yates scrambling,S-box substitution and diffusion are employed for the first round of encryption.The chaotic sequence is adopted for secondary encryption to scramble the ciphertext obtained in the first round.Then,three-dimensional filter is applied to diffusion for further useful information hiding.The key to the algorithm is generated by the combination of hash value of plaintext image and the input parameters.It improves resisting ability of plaintext attacks.The security analysis shows that the algorithm is effective and efficient.It can resist common attacks.In addition,the good diffusion effect shows that the scheme can solve the differential attacks encountered in the transmission of medical images and has positive implications for future research. 展开更多
关键词 medical image encryption Fisher-Yates scrambling three-dimensional filter diffusion bidirectional diffusion S-box substitution
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基于频域注意力Diffusion Transformer的SAR舰船图像生成技术
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作者 黄文宇 熊刚 +1 位作者 舒汀 郁文贤 《现代雷达》 北大核心 2025年第11期52-57,共6页
目前,基于生成对抗网络的合成孔径雷达(SAR)图像生成方法受限于训练过程中的固有不稳定性,而基于扩散模型的方法仍主要依赖于传统的U-Net骨干网络。文中提出了一种新颖的扩散模型架构——SpectDiT,旨在实现高质量的SAR图像生成。该模型... 目前,基于生成对抗网络的合成孔径雷达(SAR)图像生成方法受限于训练过程中的固有不稳定性,而基于扩散模型的方法仍主要依赖于传统的U-Net骨干网络。文中提出了一种新颖的扩散模型架构——SpectDiT,旨在实现高质量的SAR图像生成。该模型将频谱层与Transformer注意力层相结合,在扩散过程中引入频域特征建模,从而进一步提升SAR图像的质量与真实性。与传统的去噪扩散概率模型及基于全注意力Transformer的扩散Transformer相比,SpectDiT在SAR图像生成任务中表现更为优越,尤其在峰值信噪比、结构相似度和感知图像块相似度等指标上取得了新的最优性能。值得注意的是,SpectDiT具备灵活的架构设计,可通过调整频谱层与注意力层的比例来适应不同的生成任务。作为一种新的扩散模型骨干网络,SpectDiT为SAR图像合成开辟了新的方向,具备拓展至其他领域图像生成任务的潜力。 展开更多
关键词 去噪扩散概率模型 扩散Transformer 合成孔径雷达图像生成 频域学习
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Influence of Al,Cu and Mn additions on diffusion behaviors in CoCrFeNi high-entropy alloys 被引量:1
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作者 Juan CHEN Zhen-zhong ZHANG +1 位作者 Jin-kun XIAO Li-jun ZHANG 《Transactions of Nonferrous Metals Society of China》 2025年第1期184-193,共10页
The interdiffusion coefficients in Al_(0.2)CoCrFeNi,CoCrCu_(0.2)FeNi,and CoCrFeMn_(0.2)Ni high-entropy alloys were efficiently determined by combining diffusion couple experiments and high-throughput determination of ... The interdiffusion coefficients in Al_(0.2)CoCrFeNi,CoCrCu_(0.2)FeNi,and CoCrFeMn_(0.2)Ni high-entropy alloys were efficiently determined by combining diffusion couple experiments and high-throughput determination of interdiffusion coefficients(HitDIC)software at 1273−1373 K.The results show that the addition of Al,Cu,and Mn to CoCrFeNi high-entropy alloys promotes the diffusion of Co,Cr,and Fe atoms.The comparison of tracer diffusion coefficients indicates that there is no sluggish diffusion in tracer diffusion on the thermodynamic temperature scale for the present Al_(0.2)CoCrFeNi,CoCrCu_(0.2)FeNi,and CoCrFeMn_(0.2)Ni high-entropy alloys.The linear relationship between diffusion entropy and activation energy reveals that the diffusion process of atoms is unaffected by an increase in the number of components as long as the crystal structure remains unchanged. 展开更多
关键词 Co−Cr−Fe−Ni high-entropy alloy diffusION interdiffusivity diffusion couple
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