Recrystallization stands as an essential process that influences the microstructure and properties of magnesium(Mg)alloys,yet its mechanisms remain complex and multifaceted.This review explores the key factors affecti...Recrystallization stands as an essential process that influences the microstructure and properties of magnesium(Mg)alloys,yet its mechanisms remain complex and multifaceted.This review explores the key factors affecting the recrystallization behavior of Mg alloys,emphasizing how their unique structural characteristics impact the driving forces and dynamics of recrystallization.Unlike conventional alloys,Mg alloys exhibit distinctive recrystallization kinetics,which is significantly affected by deformation conditions,such as strain rate,temperature,and processing methods(e.g.,rolling,forging,and extrusion).The process is also influenced by material characteristics,including initial grain size,texture,dislocation density,solute clustering,and stacking fault energy.Additionally,uneven strain distribution,stress concentrations,and stored energy play crucial roles in shaping the formation of recrystallized grains,particularly near grain boundaries.Notably,recrystallization is driven by dislocation accumulation and the availability of slip systems,with new strain-free grains typically forming in regions of high dislocation density.This paper synthesizes the existing literature to provide a comprehensive understanding of the mechanisms and kinetics of recrystallization in Mg alloys,highlighting the influence of microstructural features such as second-phase particles and grain boundary characteristics.It also identifies key challenges and suggests promising directions for future research,including optimizing material compositions and the interaction between deformation conditions via machine learning.展开更多
This paper discusses the development characteristics of urban horticulture under the background of smart agriculture,as well as the application of artificial intelligence technology in it.It analyzes the importance of...This paper discusses the development characteristics of urban horticulture under the background of smart agriculture,as well as the application of artificial intelligence technology in it.It analyzes the importance of highly skilled talents in urban agriculture in the era of smart agriculture and their cultivation pathways and practices.It proposes measures such as building multi-level practical teaching platforms,implementing the“Enjoy Horticulture”series of high-quality activities,and establishing the“1234”applied talent training model to cultivate high-quality talents that meet the development needs of modern urban horticulture industry.Taking Beijing University of Agriculture and other universities as examples,the paper analyzes the practical cases and effects of the urban horticulture discipline’s industry-education-research collaborative talent training model,which has reference significance for further improving and perfecting the urban horticulture industry-education-research collaborative talent training plan.展开更多
Large models,exemplified by ChatGPT,have reached the pinnacle of contemporary artificial intelligence(AI).However,they are plagued by three inherent drawbacks:excessive training data and computing power consumption,su...Large models,exemplified by ChatGPT,have reached the pinnacle of contemporary artificial intelligence(AI).However,they are plagued by three inherent drawbacks:excessive training data and computing power consumption,susceptibility to catastrophic forgetting,and a deficiency in logical reasoning capabilities within black-box models.To address these challenges,we draw insights from human memory mechanisms to introduce“machine memory,”which we define as a storage structure formed by encoding external information into a machine-representable and computable format.Centered on machine memory,we propose the brand-new machine memory intelligence(M^(2)I)framework,which encompasses representation,learning,and reasoning modules and loops.We explore the key issues and recent advances in the four core aspects of M^(2)I,including neural mechanisms,associative representation,continual learning,and collaborative reasoning within machine memory.M^(2)I aims to liberate machine intelligence from the confines of data-centric neural networks and fundamentally break through the limitations of existing large models,driving a qualitative leap from weak to strong AI.展开更多
In recent years,with the rapid development of next-generation digital technologies,the vigorous growth of the digital economy,and the continuous deepening of the strategy to build a strong education nation,the digital...In recent years,with the rapid development of next-generation digital technologies,the vigorous growth of the digital economy,and the continuous deepening of the strategy to build a strong education nation,the digital transformation of vocational education has increasingly become a focal point.This trend has prompted researchers to delve into the background of digital transformation in vocational education,the current challenges and difficulties it faces,and actively seek effective pathways to enhance vocational education quality through digital transformation.It also explores how to better leverage the potential of digital technologies in educational services.Against this backdrop,this paper employs CiteSpace software to conduct a visual analysis of research literature related to digital transformation and vocational education,aiming to outline the research hotspots and evolutionary trends in this field.Based on the analysis results,the paper further proposes constructive suggestions and prospects for the future development direction of vocational education digital transformation.展开更多
While Role-Based Access Control Model (RBAC) is being analyzed, the concept of Role of Time-domain Based Access Control Model (T-RBAC) is put forward. With time-domain added, both time-domain and authority control rol...While Role-Based Access Control Model (RBAC) is being analyzed, the concept of Role of Time-domain Based Access Control Model (T-RBAC) is put forward. With time-domain added, both time-domain and authority control roles. The basic idea of T-RBAC is introduced and described formally, and the safely of this model is analyzed. The research shows that T-RBAC fulfills both rules of information security, which are principle of least privilege and separation of duties. With practical application of T-RBCA, it can handle most of the time-related or authority-related problems. What’s more, it also increases the security level, flexibility and dynamic adaptation of the system and has lower complexity than system only handled by authority. This model also can solve conflicts caused by authority.展开更多
High-entropy alloys(HEAs)are an emerging and rapidly developing family of alloys with appealing properties such as lightweight HEAs with excellent mechanical properties.In this study,to obtain lightweight HEAs with ex...High-entropy alloys(HEAs)are an emerging and rapidly developing family of alloys with appealing properties such as lightweight HEAs with excellent mechanical properties.In this study,to obtain lightweight HEAs with exceptional hardness,we prepared AlCrTiV_(0.5)Cu_(x)(x=0,0.2,0.4,0.6,0.8 and 1.0,denoted as Cu_(0),Cu_(0.2),Cu_(0.4),Cu_(0.6),Cu_(0.8) and Cu_(1.0) alloys,respectively)HEAs and analyzed their microstructure and hardness.展开更多
Twinning is widely recognized as an effective and cost-efficient method for controlling the microstructure and properties of wrought magnesium(Mg)alloys.Specifically,twins play a crucial role in initiating dynamic rec...Twinning is widely recognized as an effective and cost-efficient method for controlling the microstructure and properties of wrought magnesium(Mg)alloys.Specifically,twins play a crucial role in initiating dynamic recrystallization(DRX),while twin regions experience rapid recrystallization during static recrystallization(SRX).The activation of twinning can lead to changes in lattice orientation,significantly impacting the final texture in Mg alloys.The active roles of twinning are influenced by various factors during the activation process,and the mobility of twin boundaries(TB)can be amplified by stress effects,dislocation interactions,and thermal effects.Conversely,annealing treatments that involve proper segregation or precipitation on TBs serve to stabilize them,restraining their motion.Events such as segregation may also alter the twinning propensity in Magnesium-rare earth(Mg-RE)alloys.While{10–11}contraction twins(CT)and{10–11}-{10–12}double twins(DT)can promote dynamic recrystallization(DRX),they also pose a risk as potential sources of voids and cracks.Additionally,understanding the nucleation and growth mechanisms of twinning is crucial,and these aspects are briefly reviewed in this article.Considering the factors mentioned above,this article summarizes the recent research progress in this field,shedding light on advancements in recent eras.展开更多
基金funding by the National Natural Science Foundation of China(Grant number U22A20187)(Grant No.52271147,No.52471175)China Postdoctoral Science Foundation(grant number 2024M751172)。
文摘Recrystallization stands as an essential process that influences the microstructure and properties of magnesium(Mg)alloys,yet its mechanisms remain complex and multifaceted.This review explores the key factors affecting the recrystallization behavior of Mg alloys,emphasizing how their unique structural characteristics impact the driving forces and dynamics of recrystallization.Unlike conventional alloys,Mg alloys exhibit distinctive recrystallization kinetics,which is significantly affected by deformation conditions,such as strain rate,temperature,and processing methods(e.g.,rolling,forging,and extrusion).The process is also influenced by material characteristics,including initial grain size,texture,dislocation density,solute clustering,and stacking fault energy.Additionally,uneven strain distribution,stress concentrations,and stored energy play crucial roles in shaping the formation of recrystallized grains,particularly near grain boundaries.Notably,recrystallization is driven by dislocation accumulation and the availability of slip systems,with new strain-free grains typically forming in regions of high dislocation density.This paper synthesizes the existing literature to provide a comprehensive understanding of the mechanisms and kinetics of recrystallization in Mg alloys,highlighting the influence of microstructural features such as second-phase particles and grain boundary characteristics.It also identifies key challenges and suggests promising directions for future research,including optimizing material compositions and the interaction between deformation conditions via machine learning.
基金The Enhancement Project of Young Teachers Research Innovation Ability(JKC2022006)Beijing Municipal Higher Education Institutions’Teacher Team Construction Support Plan-High-Level Teaching Innovation Team(BPHR20220211)+1 种基金Beijing Higher Education Undergraduate Teaching Reform and Innovation Project(2023003)2024 Beijing University of Agriculture Student Party Members“Vanguard Force Action”Project。
文摘This paper discusses the development characteristics of urban horticulture under the background of smart agriculture,as well as the application of artificial intelligence technology in it.It analyzes the importance of highly skilled talents in urban agriculture in the era of smart agriculture and their cultivation pathways and practices.It proposes measures such as building multi-level practical teaching platforms,implementing the“Enjoy Horticulture”series of high-quality activities,and establishing the“1234”applied talent training model to cultivate high-quality talents that meet the development needs of modern urban horticulture industry.Taking Beijing University of Agriculture and other universities as examples,the paper analyzes the practical cases and effects of the urban horticulture discipline’s industry-education-research collaborative talent training model,which has reference significance for further improving and perfecting the urban horticulture industry-education-research collaborative talent training plan.
基金supported by the National Natural Science Foun-dation of China(62137002,62250009,62202367,82025020,and 82230072).
文摘Large models,exemplified by ChatGPT,have reached the pinnacle of contemporary artificial intelligence(AI).However,they are plagued by three inherent drawbacks:excessive training data and computing power consumption,susceptibility to catastrophic forgetting,and a deficiency in logical reasoning capabilities within black-box models.To address these challenges,we draw insights from human memory mechanisms to introduce“machine memory,”which we define as a storage structure formed by encoding external information into a machine-representable and computable format.Centered on machine memory,we propose the brand-new machine memory intelligence(M^(2)I)framework,which encompasses representation,learning,and reasoning modules and loops.We explore the key issues and recent advances in the four core aspects of M^(2)I,including neural mechanisms,associative representation,continual learning,and collaborative reasoning within machine memory.M^(2)I aims to liberate machine intelligence from the confines of data-centric neural networks and fundamentally break through the limitations of existing large models,driving a qualitative leap from weak to strong AI.
基金a phased achievement of the Modern Animal Husbandry Professional Group of Guangxi Agricultural Vocational University of Technology-a high-level professional group under the second round of the“Double High-Level Plan”in the Guangxi Zhuang Autonomous Region2025 university-level teaching research and reform project titled“Study on the Content,Carriers and Cultivation Mechanism of College Counselors’Artificial Intelligence Literacy from the Perspective of New-Quality Ideological and Political Competence”(XJG2552)2022 University-level Project of Humanities,Philosophy and Social Sciences Research,Guangxi Agricultural Vocational and Technical University:Exploration and Practice on the Construction of Counselor Performance Appraisal System in Vocational Undergraduate Colleges(YZS2213).
文摘In recent years,with the rapid development of next-generation digital technologies,the vigorous growth of the digital economy,and the continuous deepening of the strategy to build a strong education nation,the digital transformation of vocational education has increasingly become a focal point.This trend has prompted researchers to delve into the background of digital transformation in vocational education,the current challenges and difficulties it faces,and actively seek effective pathways to enhance vocational education quality through digital transformation.It also explores how to better leverage the potential of digital technologies in educational services.Against this backdrop,this paper employs CiteSpace software to conduct a visual analysis of research literature related to digital transformation and vocational education,aiming to outline the research hotspots and evolutionary trends in this field.Based on the analysis results,the paper further proposes constructive suggestions and prospects for the future development direction of vocational education digital transformation.
文摘While Role-Based Access Control Model (RBAC) is being analyzed, the concept of Role of Time-domain Based Access Control Model (T-RBAC) is put forward. With time-domain added, both time-domain and authority control roles. The basic idea of T-RBAC is introduced and described formally, and the safely of this model is analyzed. The research shows that T-RBAC fulfills both rules of information security, which are principle of least privilege and separation of duties. With practical application of T-RBCA, it can handle most of the time-related or authority-related problems. What’s more, it also increases the security level, flexibility and dynamic adaptation of the system and has lower complexity than system only handled by authority. This model also can solve conflicts caused by authority.
基金financially supported by the National Natural Science Foundation of China (No.51871129)the Open Funding of State Key Laboratory for Advanced Metals and Materials (No.2020-Z10)
文摘High-entropy alloys(HEAs)are an emerging and rapidly developing family of alloys with appealing properties such as lightweight HEAs with excellent mechanical properties.In this study,to obtain lightweight HEAs with exceptional hardness,we prepared AlCrTiV_(0.5)Cu_(x)(x=0,0.2,0.4,0.6,0.8 and 1.0,denoted as Cu_(0),Cu_(0.2),Cu_(0.4),Cu_(0.6),Cu_(0.8) and Cu_(1.0) alloys,respectively)HEAs and analyzed their microstructure and hardness.
基金supported by the National Natural Science Foundation of China(No.U22A20187,No.52271147,No.12261160364).
文摘Twinning is widely recognized as an effective and cost-efficient method for controlling the microstructure and properties of wrought magnesium(Mg)alloys.Specifically,twins play a crucial role in initiating dynamic recrystallization(DRX),while twin regions experience rapid recrystallization during static recrystallization(SRX).The activation of twinning can lead to changes in lattice orientation,significantly impacting the final texture in Mg alloys.The active roles of twinning are influenced by various factors during the activation process,and the mobility of twin boundaries(TB)can be amplified by stress effects,dislocation interactions,and thermal effects.Conversely,annealing treatments that involve proper segregation or precipitation on TBs serve to stabilize them,restraining their motion.Events such as segregation may also alter the twinning propensity in Magnesium-rare earth(Mg-RE)alloys.While{10–11}contraction twins(CT)and{10–11}-{10–12}double twins(DT)can promote dynamic recrystallization(DRX),they also pose a risk as potential sources of voids and cracks.Additionally,understanding the nucleation and growth mechanisms of twinning is crucial,and these aspects are briefly reviewed in this article.Considering the factors mentioned above,this article summarizes the recent research progress in this field,shedding light on advancements in recent eras.
