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Global Stability of Traveling Wavefronts for a Belousov-Zhabotinsky Model with Mixed Nonlocal and Degenerate Diffusions 认领 引用
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作者 Yuting YANG Guobao ZHANG 《Journal of Mathematical Research with Applications》 CSCD 2026年第1期87-102,共16页
In this paper,we are concerned with the stability of traveling wavefronts of a Belousov-Zhabotinsky model with mixed nonlocal and degenerate diffusions.Such a system can be used to study the competition among nonlocal... In this paper,we are concerned with the stability of traveling wavefronts of a Belousov-Zhabotinsky model with mixed nonlocal and degenerate diffusions.Such a system can be used to study the competition among nonlocally diffusive species and degenerately diffusive species.We prove that the traveling wavefronts are exponentially stable,when the initial perturbation around the traveling waves decays exponentially as x→-∞,but in other locations,the initial data can be arbitrarily large.The adopted methods are the weighted energy with the comparison principle and squeezing technique. 展开更多
关键词 Belousov-Zhabotinsky model nonlocal diffusion stability comparison principle weighted energy
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A RISK-SENSITIVE STOCHASTIC MAXIMUM PRINCIPLE FOR OPTIMAL CONTROL OF JUMP DIFFUSIONS AND ITS APPLICATIONS 认领 引用 被引量：3
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作者 史敬涛 吴臻 《Acta Mathematica Scientia》 SCIE CSCD 2011年第2期419-433,共15页
A stochastic maximum principle for the risk-sensitive optimal control prob- lem of jump diffusion processes with an exponential-of-integral cost functional is derived assuming that the value function is smooth, where ... A stochastic maximum principle for the risk-sensitive optimal control prob- lem of jump diffusion processes with an exponential-of-integral cost functional is derived assuming that the value function is smooth, where the diffusion and jump term may both depend on the control. The form of the maximum principle is similar to its risk-neutral counterpart. But the adjoint equations and the maximum condition heavily depend on the risk-sensitive parameter. As applications, a linear-quadratic risk-sensitive control problem is solved by using the maximum principle derived and explicit optimal control is obtained. 展开更多
关键词 Risk-sensitive control jump diffusions maximum principle adioint equation
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Adsorptions and diffusions of carbon atoms on the surface and in the subsurface of Co(200): A first-principles density-functional study 认领 引用 被引量：1
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作者 乔靓 王淑敏 +3 位作者 张晓明 胡小颖 曾毅 郑伟涛 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第8期75-80,共6页
First-principles calculations based on density functional theory are used to investigate the adsorptions and diffusions of carbon atoms on the surface and in the subsurface of Co （200）. The preferred site for the ca... First-principles calculations based on density functional theory are used to investigate the adsorptions and diffusions of carbon atoms on the surface and in the subsurface of Co （200）. The preferred site for the carbon atom on the surface is the hollow site, and the preferred site in the subsurface is the octahedral site. There is charge transfer from the surface to the adsorbed carbon atom, and for the most favorable adsorbed structure the charge transfer is largest. Moreover, the energy barriers for the diffusions of carbon atoms on the surface and from the surface into the subsurface and then back to the surface are calculated in detail. The results indicate that the energy barrier for the diffusion of carbon atoms on the surface is comparable to that from the subsurface to the surface. The results imply that both the direct surface nucleation and the surface segregation from Co bulk can be observed in the chemical vapor deposition growth of graphene on Co （200） substrate, which can gain a new insight into the growth mechanism of graphene. 展开更多
关键词 adsorption diffusion carbon Co surface first-principles calculations
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Practical stability and instability of regime-switching diffusions 认领 引用
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作者 G. George YIN Bo ZHANG Chao ZHU 《控制理论与应用（英文版）》 2008年第2期105-114,共10页
This work is devoted to practical stability of a class of regime-switching diffusions. First, the notion of practical stability is introduced. Then, sufficient conditions for practical stability and practical instabil... This work is devoted to practical stability of a class of regime-switching diffusions. First, the notion of practical stability is introduced. Then, sufficient conditions for practical stability and practical instability in probability and in pth mean are provided using a Lyapunov function argument. In addition, easily verifiable conditions on drift and diffusion coefficients are also given. Moreover, examples are supplied for demonstration purposes. 展开更多
关键词 Regime-switching diffusion Practical stability Practical instability Sufficient condition
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A New Method to Estimate Nonlinear Diffusions Based on Discretely Observed Data 认领 引用
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作者 杜本峰 郭兴义 杨俊龙 《Chinese Quarterly Journal of Mathematics》 2002年第2期94-100,共7页
The paper proposes a new method to estimate nonlinear diffusions based on discretely observed data, and gives some properties of the corresponding parameters estimation.
关键词 diffusion GARCH PML limit theory
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A NOTE ON STOCHASTIC OPTIMAL CONTROL OF REFLECTED DIFFUSIONS WITH JUMPS 认领 引用
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作者 丁灯 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2000年第9期1079-1090,共12页
Stochastic optimal control problems for a class of reflected diffusion with Poisson jumps in a half-space are considered. The nonlinear Nisio' s semigroup for such optimal control problems was constructed. A Hamil... Stochastic optimal control problems for a class of reflected diffusion with Poisson jumps in a half-space are considered. The nonlinear Nisio' s semigroup for such optimal control problems was constructed. A Hamilton-Jacobi-Bellman equation with the Neumann boundary condition associated with this semigroup was obtained. Then, viscosity solutions of this equation were defined and discussed, and various uniqueness of this equation was also considered. Finally, the value function was such optimal control problems is shown to be a viscosity solution of this equation. 展开更多
关键词 stochastic optimal control reflected diffusion with jumps Hamilton-Jacobi-Bellman equation viscosity solution
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Necessary Conditions for Optimal Control of Diffusions with Hard Terminal State Restrictions 认领 引用
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作者 Atle Seierstad 《Open Journal of Optimization》 2018年第1期1-40,共40页
Necessary conditions are proved for certain problems of optimal control of diffusions where hard end constraints occur. The main results apply to several dimensional problems, where some of the state equations involve... Necessary conditions are proved for certain problems of optimal control of diffusions where hard end constraints occur. The main results apply to several dimensional problems, where some of the state equations involve Brownian motions, but not the equations corresponding to states being hard restricted at the terminal time. The necessary conditions are stated in terms of weak variations. Two versions of necessary conditions are given, one version involving solutions of variational equations, the other one involving first order adjoint equations. 展开更多
关键词 Optimal Control Diffusions Hard Terminal State Restrictions
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Technology Sub-diffusions:Consumptive Motivations for Mobile Phone Calls and Digital Services 认领 引用
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作者 Chih-Peng Chu Chen-Ju Lin Jin-Gu Pan 《China Communications》 SCIE 2008年第4期120-128,共9页
Digital services interfaced with mobile phone lines are gradually being regarded as a core product in this modern age due to the high transmission speed of mobile technology.The research in this paper is based on the ... Digital services interfaced with mobile phone lines are gradually being regarded as a core product in this modern age due to the high transmission speed of mobile technology.The research in this paper is based on the concept of product inter-dependence and actively explores the different consumptive motivations between the consumers'behavior of phone-call users and those who use digital services.This study also attempts to use a modifi ed diffusion model to estimate the consumers'collective behavior with a longitudinal approach.In this study,it can be inferred that psychological consumer motivations should dominate marketing policies.Thus,it was found that digital service users have more self-motivation and autonomy when adopting a new product because they have significantly higher innovative at-tributes than the segment of phone-call users.With these findings,we claim that we have discovered an unprec-edented concept for marketing managers who welcome the challenges of mobile digital services in the future. 展开更多
关键词 Inter-dependent products Technology diffusion Mobile telecommunication Digital services Consumptive motivations
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PERSISTENCE OF TWO-SPECIES AYALA COMPETITIVE MODEL WITH DIFFERENT DIFFUSIONS 认领 引用
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作者 原存德 裴永珍 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1999年第4期118-125,共8页
In this paper, the stabilities of boundary equilibrium and positive equilibrium of two_species Ayala competitive systems with two different diffusions are discussed, and dynamic behaviors of species are obtained. At t... In this paper, the stabilities of boundary equilibrium and positive equilibrium of two_species Ayala competitive systems with two different diffusions are discussed, and dynamic behaviors of species are obtained. At the same time, the dynamic behaviors between systems with diffusion and those without diffusion are compared. This shows the influence of diffusions on the persistence of species. 展开更多
关键词 nonlinear competitive system diffusion equilibrium persistence
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On the Dynamics of Controlled Diffusions 认领 引用
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作者 杨明炎 梅凤翔 《Journal of Beijing Institute of Technology》 EI CAS 1997年第1期30-36,共7页
Treats of dynamical systems with finite number of degrees of freedom such that the time evolution of the configuration variables for given initial conditions can well be described by controlled diffusions.Two suitable... Treats of dynamical systems with finite number of degrees of freedom such that the time evolution of the configuration variables for given initial conditions can well be described by controlled diffusions.Two suitable forms of stochastic action associated with the controlled diffusions are introduced in the general framework of stochastic control theory.By discretizing the stochastic action,the dynamical equations for the controlled diffusions of the given systems are derived in terms of generalized coordinates.These equations,together with the continuity equation,describe exactly the probability approach of the diffusion motion. 展开更多
关键词 diffusion stochastic mechanics action variation
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The genetic history around the southeastern Mongolian Plateau traces Neolithic cultural diffusions in northern East Asia 认领 引用 被引量：1
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作者 Tianxiang Liu Zhanhu Zhao +15 位作者 Mingjian Guo EAndrew Bennett Peng Cao Lina Zhuang Qingyan Dai Wenrui Zhang Feng Liu Han Shi Meiling Song Tianyi Wang Fan Bai Jingkun Ran Wanjing Ping Ganyu Zhang Xiaotian Feng Qiaomei Fu 《The Innovation》 EI 2026年第1期75-86,共12页
Cultural and material exchange between groups across the mountainous region separating the East Asian Steppe and the plains and river valleys of northern East Asia has been documented since the Paleolithic,yet the ext... Cultural and material exchange between groups across the mountainous region separating the East Asian Steppe and the plains and river valleys of northern East Asia has been documented since the Paleolithic,yet the extent to which these interactions reflect prehistoric population dynamics is unknown.By sequencing and analyzing 35 ancient genomes from the southeastern Mongolian Plateau,spanning from 8,800 to 5,000 years ago,we found that Early Holocene populations from the southeastern Mongolian Plateau shared a common ancestry.We show this ancestry,which was predominant in steppe populations before the Holocene and may have been associated with the post-Last Glacial Maximum(LGM)microblade dispersal,to have lasted on the southeastern Mongolian Plateau until between 7,500 and 5,700 years ago,during which time it contributed to the West Liao River basin populations associated with the Hongshan culture.The continuity of the Early Holocene southeastern Mongolian Plateau ancestry was later disrupted by genetic influxes from both the northeastern Mongolian Plateau and West Liao River Hongshan populations,coinciding with cultural diffusion between 5,700 and 5,000 years ago.These revealed complex genetic and cultural interactions along the Eastern Steppe in the period between the LGM and the Middle Holocene. 展开更多
关键词 cultural material exchange genetic history neolithic cultural diffusions prehistoric population dynamics southeastern mongolian plateau paleolithic east asian steppe sequencing analyzing ancient genomes
The Voice of Physics in Finance:A Glance on the Theoretical Application of Heat Equation to Stock Price Diffusions 认领 引用
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作者 Leonard Mushunje 《Journal of Economic Science Research》 2021年第1期1-4,共4页
Stock price volatility is considered the main matter of concern within the investment grounds.However,the diffusivity of these prices should as well be considered.As such,proper modelling should be done for investors ... Stock price volatility is considered the main matter of concern within the investment grounds.However,the diffusivity of these prices should as well be considered.As such,proper modelling should be done for investors to stay healthy-informed.This paper suggest to model stock price diffusions using the heat equation from physics.We hypothetically state that,our model captures and model the diffusion bubbles of stock prices with a better precision of reality.We compared our model with the standard geometric Brownian motion model which is the wide commonly used stochastic differential equation in asset valuation.Interestingly,the models proved to agree as evidenced by a bijective relation between the volatility coefficients of the Brownian motion model and the diffusion coefficients of our heat diffusion model as well as the corresponding drift components.Consequently,a short proof for the martingale of our model is done which happen to hold. 展开更多
关键词 Stock prices Volatility Diffusion Heat equation Brownian motion model Physics
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Estimation in Interacting Diffusions: Continuous and Discrete Sampling 认领 引用
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作者 Jaya Prakash Narayan Bishwal 《Applied Mathematics》 2011年第9期1154-1158,共5页
Consistency and asymptotic normality of the sieve estimator and an approximate maximum likelihood estimator of the drift coefficient of an interacting particles of diffusions are studied. For the sieve estimator, obse... Consistency and asymptotic normality of the sieve estimator and an approximate maximum likelihood estimator of the drift coefficient of an interacting particles of diffusions are studied. For the sieve estimator, observations are taken on a fixed time interval [0,T] and asymptotics are studied as the number of interacting particles increases with the dimension of the sieve. For the approximate maximum likelihood estimator, discrete observations are taken in a time interval [0,T] and asymptotics are studied as the number of interacting particles increases with the number of observation time points. 展开更多
关键词 Stochastic Differential Equations Mean-Field Model Large Interacting Systems Diffusion Process Discrete Observations Approximate Maximum Likelihood Estimation Sieve Estimation
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Inverse local time of one-dimensional diffusions and its comparison theorem 认领 引用
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作者 Zhen-Qing Chen Lidan Wang 《Science China Mathematics》 SCIE CSCD 2025年第5期1201-1218,共18页
In this paper,we study the inverse local times at 0 of one-dimensional reflected diffusions on[0,∞)and establish a comparison principle for these inverse local times.We also provide applications to Green function est... In this paper,we study the inverse local times at 0 of one-dimensional reflected diffusions on[0,∞)and establish a comparison principle for these inverse local times.We also provide applications to Green function estimates for non-local operators. 展开更多
关键词 diffusion local time inverse local time subordinator Lévy measure Girsanov transform comparison theorem Green function estimate
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Generative Semantic Communication:Architectures,Technologies,and Applications 认领 引用 被引量：4
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作者 Jinke Ren Yaping Sun +7 位作者 Hongyang Du Weiwen Yuan Chongjie Wang Xianda Wang Yingbin Zhou Ziwei Zhu Fangxin Wang Shuguang Cui 《Engineering》 SCIE EI CSCD 2026年第1期45-61,共17页
Semantic communication(SemCom)has emerged as a transformative paradigm for future wireless networks,aiming to improve communication efficiency by transmitting only the semantic meaning(or its encoded version)of the so... Semantic communication(SemCom)has emerged as a transformative paradigm for future wireless networks,aiming to improve communication efficiency by transmitting only the semantic meaning(or its encoded version)of the source data rather than the complete set of bits(symbols).However,traditional deep-learning-based SemCom systems present challenges such as limited generalization,low robustness,and inadequate reasoning capabilities,primarily due to the inherently discriminative nature of deep neural networks.To address these limitations,generative artificial intelligence(GAI)is seen as a promising solution,offering notable advantages in learning complex data distributions,transforming data between high-and low-dimensional spaces,and generating high-quality content.This paper explores the applications of GAI in SemCom and presents a comprehensive study.It begins by introducing three widely used SemCom systems enabled by classical GAI models:variational autoencoders,generative adversarial networks,and diffusion models.For each system,the fundamental concept of the GAI model,the corresponding SemCom architecture,and a literature review of recent developments are provided.Subsequently,a novel generative SemCom system is proposed,incorporating cutting-edge GAI technology—large language models(LLMs).This system features LLM-based artificial intelligence(AI)agents at both the transmitter and receiver,which act as“brains”to enable advanced information understanding and content regeneration capabilities,respectively.Unlike traditional systems that focus on bitstream recovery,this design allows the receiver to directly generate the desired content from the coded semantic information sent by the transmitter.As a result,the communication paradigm shifts from“information recovery”to“information regeneration,”marking a new era in generative SemCom.A case study on point-to-point video retrieval is presented to demonstrate the effectiveness of the proposed system,showing a 99.98%reduction in communication overhead and a 53%improvement in average retrieval accuracy compared to traditional communication systems.Furthermore,four typical application scenarios for generative SemCom are described,followed by a discussion of three open issues for future research.In summary,this paper provides a comprehensive set of guidelines for applying GAI in SemCom,laying the groundwork for the efficient deployment of generative SemCom in future wireless networks. 展开更多
关键词 Semantic communication Generative artificial intelligence Large language model Variational autoencoder Generative adversarial network Diffusion model
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Revealing the Hydrogen Permeation Mechanism in Polyetheretherketone and Polytetrafluoroethylene:From Experimental Validation to Molecular-level Interpretation 认领 引用 被引量：1
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作者 Hong-Lin Zhang Wen-Tao Hu +2 位作者 Jie Xiao Tian-Lei Li Yuan-Hua Lin 《Chinese Journal of Polymer Science》 SCIE EI CAS CSCD 2026年第1期278-298,I0019,共21页
This study integrates experimental investigation with molecular dynamics simulations to elucidate the hydrogen transport mechanisms in polyetheretherketone(PEEK)and polytetrafluoroethylene(PTFE),offering fundamental i... This study integrates experimental investigation with molecular dynamics simulations to elucidate the hydrogen transport mechanisms in polyetheretherketone(PEEK)and polytetrafluoroethylene(PTFE),offering fundamental insights into the barrier properties of high-performance polymeric materials.Experimental results demonstrate that PEEK exhibits superior hydrogen barrier performance compared to PTFE at both ambient and elevated temperatures.However,detailed molecular dynamics simulations uncover a distinctive,enthalpy-driven"high solubility-low diffusivity"transport mechanism:although PEEK displays higher hydrogen solubility due to its stronger thermodynamic affinity,its diffusion coefficient is markedly lower than that of PTFE.This mechanism remains operative across a broad operational temperature range(233 K to358 K),yet its influence on overall permeability is strongly temperature-dependent.At room and high temperatures,the exceptionally low diffusivity of PEEK governs the entire permeation process,establishing its effectiveness as a high-performance hydrogen barrier material.In contrast,under low-temperature conditions(e.g.,233 K),the general suppression of diffusion allows the high solubility of PEEK to dominate,resulting in greater overall permeability than PTFE and giving rise to a performance“reversal”phenomenon.This distinct transport behavior originates from the strong non-covalent interactions between hydrogen molecules and the aromatic rings as well as polar functional groups present in the amorphous regions of PEEK,which simultaneously enhance solubility and impose significant kinetic energy barriers.The"structure-mechanism"correlation framework established in this work provides a robust theoretical foundation for the rational design of next-generation hydrogen barrier materials tailored to specific operational temperature requirements. 展开更多
关键词 Hydrogen permeation Polytetrafluoroethylene/polyetheretherketone Molecular dynamics simulation High solubility-low diffusivity
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Molecular dynamics simulation on surface hydration of different cationic montmorillonite 认领 引用 被引量：1
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作者 WANG Yue-peng LIU Xin +1 位作者 LIU Xiang-jun TANG Shi-bin 《Journal of Central South University》 SCIE EI CAS CSCD 2026年第2期944-967,共24页
In order to reveal the mechanism of surface hydration differences for different types of montmorillonite crystals,the hydration processes of sodium,potassium,and calcium montmorillonite were simulated by molecular dyn... In order to reveal the mechanism of surface hydration differences for different types of montmorillonite crystals,the hydration processes of sodium,potassium,and calcium montmorillonite were simulated by molecular dynamics.These simulation results show that with the increase of the number of water molecules,the interlayer spacing of montmorillonite expands in a step-by-step manner,accompanied by volume expansion,decrease in density,and increase in self-diffusion coefficients of water molecules and cations.In addition,as the water molecular layer accumulates,the peak values of the radial distribution function between Na+/K+/Ca2+ions and Ow/Hw(oxygen or hydrogen atoms in water molecules)gradually decrease.The degree of polymerization of water intensifies before decreasing,while the elastic modulus and acoustic velocity are gradually decreasing.It is worth noting that Na+ion shows the highest tendency to hydrate,followed by Ca2+,and then K+.Among the cations studied,Ca2+ion has the highest hydration coordination number,hydration number and hydration radius.As a result,calcium montmorillonite exhibits the widest intensity range and the largest acoustic velocity.These findings can provide references for engineering practices such as oil and gas exploration,tunnel excavation,slope stabilization,and deep geological disposal. 展开更多
关键词 montmorillonite surface hydration molecular dynamics simulation radial distribution function self diffusion coefficient elasticity modulus
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Magnetic resonance imaging tracing of superparamagnetic iron oxide nanoparticle-labeled mesenchymal stromal cells for repairing spinal cord injury 认领 引用 被引量：1
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作者 Xiaoli Mai Yuanyuan Xie +12 位作者 Zhichong Wu Junting Zou Jiacheng Du Yunpeng Shen Hao Liu Bo Chen Mengxia Zhu Jiong Shi Yang Chen Bing Zhang Zezhang Zhu Bin Wang Ning Gu 《Neural Regeneration Research》 SCIE CAS CSCD 2026年第5期2031-2039,共9页
Mesenchymal stromal cell transplantation is an effective and promising approach for treating various systemic and diffuse diseases.However,the biological characteristics of transplanted mesenchymal stromal cells in hu... Mesenchymal stromal cell transplantation is an effective and promising approach for treating various systemic and diffuse diseases.However,the biological characteristics of transplanted mesenchymal stromal cells in humans remain unclear,including cell viability,distribution,migration,and fate.Conventional cell tracing methods cannot be used in the clinic.The use of superparamagnetic iron oxide nanoparticles as contrast agents allows for the observation of transplanted cells using magnetic resonance imaging.In 2016,the National Medical Products Administration of China approved a new superparamagnetic iron oxide nanoparticle,Ruicun,for use as a contrast agent in clinical trials.In the present study,an acute hemi-transection spinal cord injury model was established in beagle dogs.The injury was then treated by transplantation of Ruicun-labeled mesenchymal stromal cells.The results indicated that Ruicunlabeled mesenchymal stromal cells repaired damaged spinal cord fibers and partially restored neurological function in animals with acute spinal cord injury.T2*-weighted imaging revealed low signal areas on both sides of the injured spinal cord.The results of quantitative susceptibility mapping with ultrashort echo time sequences indicated that Ruicun-labeled mesenchymal stromal cells persisted stably within the injured spinal cord for over 4 weeks.These findings suggest that magnetic resonance imaging has the potential to effectively track the migration of Ruicun-labeled mesenchymal stromal cells and assess their ability to repair spinal cord injury. 展开更多
关键词 acute spinal cord injury diffusion tensor imaging dynamic migration mesenchymal stromal cells neural function neuronal regeneration quantitative susceptibility mapping repairability ruicun superparamagnetic iron oxide nanoparticle
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Application research of a hybrid data-and knowledge-driven artificial intelligence scientific computing model in neutron diffusion calculation for nuclear reactors 认领 引用 被引量：1
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作者 Fu-Lin Zeng Xiao-Long Zhang +1 位作者 Peng-Cheng Zhao Zi-Jing Liu 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2026年第2期223-244,共22页
Amidst the growing global emphasis on nuclear safety,the integrity of nuclear reactor systems has garnered attention in the aftermath of consequential events.Moreover,the rapid development of artificial intelligence t... Amidst the growing global emphasis on nuclear safety,the integrity of nuclear reactor systems has garnered attention in the aftermath of consequential events.Moreover,the rapid development of artificial intelligence technology has provided immense opportunities to enhance the safety and economy of nuclear energy.However,data-driven deep learning techniques often lack interpretability,which hinders their applicability in the nuclear energy sector.To address this problem,this study proposes a hybrid data-driven and knowledge-driven artificial intelligence model based on physics-informed neural networks to accurately compute the neutron flux distribution inside a nuclear reactor core.Innovative techniques,such as regional decomposition,intelligent keff(effective multiplication factor)search,and keffinversion,have been introduced for the calculation.Furthermore,hyperparameters of the model are automatically optimized using a whale optimization algorithm.A series of computational examples are used to validate the proposed model,demonstrating its applicability,generality,and high accuracy in calculating the neutron flux within the nuclear reactor.The model offers a dependable strategy for computing the neutron flux distribution in nuclear reactors for advanced simulation techniques in the future,including reactor digital twinning.This approach is data-light,requires little to no training data,and still delivers remarkably precise output data. 展开更多
关键词 Neutron diffusion equation Physics informed neural network Effective multiplication factor Whale optimization algorithm
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Inverse Design of Composite Materials Based on Latent Space and Bayesian Optimization 认领 引用 被引量：1
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作者 Xianrui Lyu Xiaodan Ren 《Computer Modeling in Engineering & Sciences》 SCIE EI 2026年第1期1-25,共25页
Inverse design of advanced materials represents a pivotal challenge in materials science.Leveraging the latent space of Variational Autoencoders(VAEs)for material optimization has emerged as a significant advancement ... Inverse design of advanced materials represents a pivotal challenge in materials science.Leveraging the latent space of Variational Autoencoders(VAEs)for material optimization has emerged as a significant advancement in the field of material inverse design.However,VAEs are inherently prone to generating blurred images,posing challenges for precise inverse design and microstructure manufacturing.While increasing the dimensionality of the VAE latent space can mitigate reconstruction blurriness to some extent,it simultaneously imposes a substantial burden on target optimization due to an excessively high search space.To address these limitations,this study adopts a Variational Autoencoder guided Conditional Diffusion Generative Model(VAE-CDGM)framework integrated with Bayesian optimization to achieve the inverse design of composite materials with targeted mechanical properties.The VAE-CDGM model synergizes the strengths of VAEs and Denoising Diffusion Probabilistic Models(DDPM),enabling the generation of high-quality,sharp images while preserving a manipulable latent space.To accommodate varying dimensional requirements of the latent space,two optimization strategies are proposed.When the latent space dimensionality is excessively high,SHapley Additive exPlanations(SHAP)sensitivity analysis is employed to identify critical latent features for optimization within a reduced subspace.Conversely,direct optimization is performed in the low-dimensional latent space of VAE-CDGM when dimensionality is modest.The results demonstrate that both strategies accurately achieve the targeted design of composite materials while circumventing the blurred reconstruction flaws of VAEs,which offers a novel pathway for the precise design of advanced materials. 展开更多
关键词 Variational autoencoder denoising diffusion generation model composite materials Bayesian opti-mization SHapley Additive exPlanations
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