The undeformed chip thickness and grinding force are key parameters for revealing the material removal mechanism in the grinding process.However,they are difficult to be well expressed due to the ununiformed protrusio...The undeformed chip thickness and grinding force are key parameters for revealing the material removal mechanism in the grinding process.However,they are difficult to be well expressed due to the ununiformed protrusion height and random position distribution of abrasive grains on the abrasive wheel surface.This study investigated the distribution of undeformed chip thickness and grinding force considering the non-uniform characteristics of abrasive wheel in the grinding of K4002 nickel-based superalloy.First,a novel grinding force model was established through a kinematic-geometric analysis and a grain-workpiece contact analysis.Then,a series of grinding experiments were conducted for verifying the model.The results indicate that the distribution of undeformed chip thickness is highly consistent with the Gaussian distribution formula.The increase in the grinding depth mainly leads to an increase in the average value of Gaussian distribution.On the contrary,the increase in the workpiece infeed speed or the decrease in the grinding speed mainly increases the standard deviation of Gaussian distribution.The average and maximum errors of the grinding force model are 4.9%and 14.6%respectively,indicating that the model is of high predication accuracy.展开更多
Rail weld irregularities are one of the primary excitation sources for vehicle-track interaction dynamics in modern high-speed railways.They can cause significant wheel-rail dynamic interactions,leading to wheel-rail ...Rail weld irregularities are one of the primary excitation sources for vehicle-track interaction dynamics in modern high-speed railways.They can cause significant wheel-rail dynamic interactions,leading to wheel-rail noise,component damage,and deterioration.Few researchers have employed the vehicle-track interaction dynamic model to study the dynamic interactions between wheel and rail induced by rail weld geometry irregularities.However,the cosine wave model used to simulate rail weld irregularities mainly focuses on the maximum value and neglects the geometric shape.In this study,novel theoretical models were developed for three categories of rail weld irregularities,based on measurements of the high-speed railway from Beijing to Shanghai.The vertical dynamic forces in the time and frequency domains were compared under different running speeds.These forces generated by the rail weld irregularities that were measured and modeled,respectively,were compared to validate the accuracy of the proposed model.Finally,based on the numerical study,the impact force due to rail weld irrregularity is modeled using an Artificial Neural Network(ANN),and the optimum combination of parameters for this model is found.The results showed that the proposed model provided a more accurate wheel/rail dynamic evaluation caused by rail weld irregularities than that established in the literature.The ANN model used in this paper can effectively predict the impact force due to rail weld irrregularity while reducing the computation time.展开更多
The purpose of this article is to provide,from the perspective of deformable solid mechanics,a correct justification for the expressions of all forces acting on the surface of a ferromagnetic material in a magnetic fi...The purpose of this article is to provide,from the perspective of deformable solid mechanics,a correct justification for the expressions of all forces acting on the surface of a ferromagnetic material in a magnetic field,initiated only by this field.It is shown that the moment of force applied to any closed body surface S,corresponding to the asymmetric part TAof the stress tensor T(denoted as the force pA),balances the mass magnetic moment Lmagacting in the volume V bounded by the surface S.The emergence of the asymmetric part TAof the stress tensor arises as a consequence of a special case within the moment theory of elasticity,the use of which is necessary for accurately describing the behavior of a ferromagnetic material in a magnetic field.The force pa acts in a plane tangential to the surface S at any point,while,in addition to this force,the normal force pn also acts on the body surface.It is shown in the article that the latter force arises as a result of a jump in the normal component of the magnetic field strength appearing at the body surface,and its expression is defined by the mass' s(ponderomotive) magnetic forces Fmag.Usually,this force is introduced based on the Maxwell stress tensor,which is used in the classical electromagnetism to represent the interaction between electromagnetic forces and mechanical momentum.However,as we believe and justify this in the article,such an approach is unacceptable in deformable solid mechanics.展开更多
Driven by technological innovation and the innovative allocation of production factors,new quality productive forces(NQPFs)are a key breakthrough and core element propelling China’s transition from a major agricultur...Driven by technological innovation and the innovative allocation of production factors,new quality productive forces(NQPFs)are a key breakthrough and core element propelling China’s transition from a major agricultural country to an advanced agricultural nation.At its core,agricultural modernization represents a frontier shift in agricultural development-a dynamic evolution of productive forces across technological forms,farmer demographics,industrial structures,and urban-rural relations.NQPFs drive the high-quality,integrated development of agricultural modernization through agricultural technological innovation,green and low-carbon practices,and the enhancement of all production factors.As NQPFs evolve and agricultural modernization advances,we must address constraints stemming from gaps in technology,models,resources,and talent.Furthermore,we must foster deep integration among industry,research,and education to develop new pathways for industrial upgrading,promote green and efficient agricultural development,and bridge existing technological gaps.These collective efforts are crucial for accelerating the high-quality development of agricultural modernization.展开更多
Nature is really powerful!Big earthquakes can make tall buildings and even whole mountains fall down.At Niagara Falls,waterfalls like crazy,filling 50 Olympic-sized pools in a minute!We know about storms like hurrican...Nature is really powerful!Big earthquakes can make tall buildings and even whole mountains fall down.At Niagara Falls,waterfalls like crazy,filling 50 Olympic-sized pools in a minute!We know about storms like hurricanes and blizzards.But there are many other strange things nature can do that might surprise you!展开更多
Higher vocational colleges are important institutions for cultivating skilled talents.With the development of new-quality productive forces,these colleges need to meet the requirements of digital transformation and im...Higher vocational colleges are important institutions for cultivating skilled talents.With the development of new-quality productive forces,these colleges need to meet the requirements of digital transformation and improve the effectiveness of talent cultivation.In the process of higher vocational education,it is essential to emphasize teaching innovation and enhance the level of digital teaching.From the perspective of new-quality productive forces,this paper analyzes the new requirements put forward for higher vocational education and proposes specific digital transformation strategies.The purpose is to improve the effectiveness of talent cultivation and accumulate experience for the subsequent digital transformation of higher vocational education.展开更多
The theory of new quality productive forces provides a foundational framework for cultivating pre-service English teachers.There is a high degree of consistency between the development of new quality productive forces...The theory of new quality productive forces provides a foundational framework for cultivating pre-service English teachers.There is a high degree of consistency between the development of new quality productive forces and the cultivation of pre-service English teachers.The development of new quality productive forces has put forward new requirements for the cultivation of pre-service English teachers,while the cultivation of pre-service English teachers will also promote the development of new quality productive forces and provide talent support for it.Currently,the cultivation of pre-service English teachers faces numerous challenges,which requires strengthening top-level program design,reconstructing the curriculum system,expanding cultivation fields for pre-service English teachers,improving the digital literacy of pre-service English teachers,deepening international exchanges and cooperation,and building an evidence-based evaluation system as a guarantee to achieve new breakthroughs in the cultivation of pre-service English teachers and promote the development of new quality productive forces.展开更多
In the realm of slope monitoring and reinforcement,traditional prestressing anchor cables are extensively used.However,these conventional methods often face limitations when applied to loess slopes,such as potential i...In the realm of slope monitoring and reinforcement,traditional prestressing anchor cables are extensively used.However,these conventional methods often face limitations when applied to loess slopes,such as potential issues with stress concentration and insufficient adaptability to the unique mechanical properties of loess,which may lead to challenges in ensuring long-term stability and effective reinforcement.Negative Poisson's ratio(NPR)anchor cables with constant resistance have emerged as a promising alternative,which can better match the engineering demands of loess slopes by providing more uniform stress distribution and adaptive deformation characteristics.The NPR cable's ability to maintain a constant resistance during deformation offers a distinct advantage over traditional methods as it can more effectively accommodate the complex and variable conditions of loess slopes.To investigate the anchoring performance of NPR cables in loess slope,the stress characteristics of NPR cable in loess medium were simulated and analysed by ABAQUS finite element software.First,static and general quasi-static analysis methods were used to simulate the NPR cable under static tensile conditions.The consistency of the simulated constant resistance deformation characteristics with experimental results found in the literature was verified.Second,the interaction model between the NPR cable coupled with the loess medium was established.Its constant resistance was calculated to be about 24.08%larger than that of NPR anchor cable while its plastic deformation was reduced by about 37.14%.The compressive stress on the contact surface between NPR cable and loess was concentrated near the free end of the sleeve,which indicated that the loess was prone to severe damage at the free end.The research results reveal the typical shear failure mechanism of NPR cable in loess medium,which provides an important theoretical basis for prevention of landslides and monitoring of loess slopes.展开更多
Currently,driven by the accelerated iteration of digital technologies such as big data,cloud computing,and artificial intelligence,the digital economy has become a crucial engine for generating new quality productive ...Currently,driven by the accelerated iteration of digital technologies such as big data,cloud computing,and artificial intelligence,the digital economy has become a crucial engine for generating new quality productive forces and promoting industrial upgrading.Building on a systematic review of the theoretical evolution and measurement methods of the digital economy and new quality productive forces,this paper outlines their enabling mechanisms,industrial synergy pathways,and policy practices,and summarizes regional disparities and spatial spillover effects.The main findings are as follows:First,the digital economy reshapes the traditional factor structure and significantly enhances total factor productivity through the permeation of data elements and technological innovation;Second,driven jointly by the consumer internet and the industrial internet,it optimizes supply–demand matching and service models while reducing operating costs and improving production efficiency;Third,policy environments and institutional coordination amplify the enabling effects,as evidenced notably in national big-data pilot zones and the“East Data West Computing”initiative.Looking ahead,empirical research should deepen the exploration of micro-level mechanisms and dynamic panel analyses,construct a measurement system of new quality productive forces that spans macro,meso,and micro scales,and investigate pathways for regional collaborative governance and green digital integration to address the complex challenges of the new era.展开更多
Digital technology is a pivotal factor in developing new quality productive forces in agriculture and building digital villages.Using digital technology as a foundation to explore viable methods for these forces is an...Digital technology is a pivotal factor in developing new quality productive forces in agriculture and building digital villages.Using digital technology as a foundation to explore viable methods for these forces is an imperative for realizing rural revitalization and fostering circular agricultural development.This paper outlines the theoretical logic of how new quality productive forces empower digital village construction,focusing on accelerating smart village initiatives,promoting rural digital production,and developing unique local resources.Based on the practical challenges currently facing digital village development,it formulates several countermeasures.These include stimulating rural industrial endogenous motivation through urban-rural industrial integration,implementing actions to enhance rural digital governance,building a contingent of rural digital talent,and improving rural digital infrastructure.The aim is to provide insights for better leveraging the dynamic role of new quality productive forces in promoting digital village construction.展开更多
From the perspective of new productive forces,the general technology curriculum in senior high schools should not only cultivate students’technical knowledge and practical abilities but also focus on the development ...From the perspective of new productive forces,the general technology curriculum in senior high schools should not only cultivate students’technical knowledge and practical abilities but also focus on the development of innovative thinking to meet the demand for interdisciplinary talents in the future society.Based on the chapter“Common Conception Methods”in the Jiangsu Education Edition of Technology and Design 1,this paper explores the implementation path of the general technology curriculum,focusing on the optimization strategies in four aspects:Project-based learning(PBL),strengthening technical practice,STEAM interdisciplinary integration,and a diversified.evaluation system It also analyzes the application of divergent thinking(brainstorming)and reverse thinking in the curriculum through cases.The research shows that optimizing teaching methods and enhancing practical links can effectively stimulate students’creativity and teamwork ability,improve the effectiveness of curriculum implementation,and provide strong support for the cultivation of future technical innovation talents.展开更多
Digital-intelligent technologies represent the advanced direction of new quality productive forces and are becoming a driving force for the digital transformation and high-quality development of the cultural industry....Digital-intelligent technologies represent the advanced direction of new quality productive forces and are becoming a driving force for the digital transformation and high-quality development of the cultural industry.Empowered by new quality productive forces,the digital cultural industry has demonstrated diverse characteristics,including the innovation of cultural production subjects,the intelligentization of production tools,the digitization of production objects,the systematization of production methods,and the diversification of production factors.Leveraging technologies such as AIGC,virtual-physical integration,and DAOs based on Web 3.0,the digital cultural industry has established an innovative paradigm,fostering a new method of AIGC production in the digital cultural industry,a new business format of virtual-physical integration,and a new collaborative ecosystem characterized by co-creation,co-building,and co-governance.Meanwhile,the innovative paradigm of the digital cultural industry also faces a series of new challenges,such as the adaptability issues with AIGC algorithm models,creative bottlenecks,and content quality control problems.Additionally,there are obstacles like the immaturity of international development channels for new business formats,the lack of cultural connotations in creative products,and the lag of the digital-intelligent governance of the industry ecosystem behind digital practices.In light of this,there is an urgent need to establish an optimization mechanism for the high-quality development of digital cultural industries driven by new quality productive forces.This includes optimizing the content production mechanism for AIGC-led high-quality innovation in the digital cultural industry;improving the leapfrog development mechanism for new digital cultural business formats through global-regional collaboration;and enhancing the accurate,high-quality governance mechanism for the digital cultural industry that is aligned with the goals of Chinese modernization.展开更多
Sustainable development,underpinned by robust systemic driving forces,is central to the growth of high-quality tourism.Therefore,identifying these forces at the regional level is crucial for advancing China’s goal of...Sustainable development,underpinned by robust systemic driving forces,is central to the growth of high-quality tourism.Therefore,identifying these forces at the regional level is crucial for advancing China’s goal of becoming a leading nation for tourism.This study accordingly constructs a new evaluation system that covers tourism market demand,industry supply,and structural transformation,and analyzes data from 31 Chinese provincial regions(2010–2019).The entropy method and spatial autocorrelation analysis were applied to examine the driving forces for sustainable regional tourism development.The results revealed that:First,at the national level,the driving forces for sustainable regional tourism development exhibited a clear upward trend from 2010 to 2019,with an acceleration in growth after 2015.However,there was significant regional heterogeneity:The eastern region displayed the highest levels of driving forces,followed by the central and western regions.Second,high-value clusters of these driving forces expanded from the eastern to the western regions,while the central provinces remained relatively balanced.Specifically,provincial regions such as Guangdong,Beijing,and Zhejiang were able to successively enter the high-value clusters,whereas the Xinjiang Uygur autonomous region,Gansu,and Qinghai consistently remained in the low-value clusters.Third,the driving forces exhibited a significant spatial agglomeration effect.The degree of clustering followed an inverted“U”trend over the study period,while the spatial patterns of the provincial regions remained relatively stable.展开更多
This study proposes a framework for the concept of“new quality productive forces”in the ice and snow economy(ISE)as a strategic response to global climate change and the demands of technological and industrial trans...This study proposes a framework for the concept of“new quality productive forces”in the ice and snow economy(ISE)as a strategic response to global climate change and the demands of technological and industrial transformation for high-quality development.These new quality productive forces in the ISE have developed alongside the zonal distribution of natural resources,strictly adhere to ecological principles,and integrate value transformation mechanisms specific to ice and snow resources.Their development is projected to generate multiple benefits across ecological,economic,and social dimensions.The new quality productive forces in the ISE are characterized by technology-driven resource development,synergistic integration across the entire ice and snow industry value chain,and a focus on high-quality,green growth.Grounded in geography and economics,the new quality productive forces in the ISE link scientific innovation,the reallocation of productive factors,and industrial upgrading within the context of resource constraints.Furthermore,they expand the growth potential of the ISE by fostering new production relations through digital,intelligent,and green integration,while advancing low-carbon,sustainable development under the guiding principle that“ice and snow landscapes are also mountains of gold and silver.”For China's ISE,these new quality productive forces emphasize rigorous resource protection,balanced human-environment relationships,a resilient integrated supply chain framework,and an efficient“dual circulation”economic model.Practical strategies include integrating production factors,optimizing spatial resource allocation,fostering industrial synergy,and adapting production relations,all aimed at advancing the sustainable and high-quality development of China's ISE.展开更多
Head injuries from vehicle collisions,falls,and sports are often the result of complex mechanisms involving both linear and angular forces.This study aims to quantitatively assess the effects of linear and angular for...Head injuries from vehicle collisions,falls,and sports are often the result of complex mechanisms involving both linear and angular forces.This study aims to quantitatively assess the effects of linear and angular force on the severity of traumatic brain injury in rats during collisions.An orthogonal experimental design was employed,facilitating the manipulation of linear velocity,rotational acceleration,and angle(light,medium,and heavy)across 54 rats.24 hours post-injury,magnetic resonance imaging T2-weighted imaging,and diffusion tensor imaging were utilized to detect abnormal brain signals,with the fractional anisotropy value of the corpus callosum serv-ing as the primary injury indicator.Anatomical analyses and immunohistological staining were conducted to measure the amyloid precursor protein(β-APP)accumulation,using integrated optical density as a secondary indicator.Entropy weighting was applied to derive index weights for the injury scoring system.Through analysis guided by analysis of variance and linear regression,it was determined that both linear and angular loadings significantly impacted brain injury severity.Increased rotational acceleration at constant linear velocities correlated with more severe injuries,whereas the rotation angle exhibited minimal effect.Linear velocity emerged as the primary determinant of injury severity,accounting for 91.5%of the variance,while rotational acceleration and rotation angle contributed 6.5%and 0.9%,respectively.These findings offer critical insights for developing protective measures against brain injuries in traffic accidents.展开更多
Bentonite is a necessary binder in producing pellets.Its excessive use reduces the iron grade of pellets and increases production costs.Minimizing bentonite dosage is essential for producing high-quality iron ore pell...Bentonite is a necessary binder in producing pellets.Its excessive use reduces the iron grade of pellets and increases production costs.Minimizing bentonite dosage is essential for producing high-quality iron ore pellets.Addressing the gap in the application of organically-intercalated modified bentonite in the pelletizing field,this study introduces an innovative modification process for bentonite that employs the synergistic effect of mechanical force and dimethyl sulfoxide to enhance the intercalation of organic compounds within bentonite,thus significantly enhancing its binding performance.The colloid value and swell capacity of modified bentonite(98.5 m L/3g and 55.0 m L/g)were much higher than the original bentonite(90.5 m L/3g and 17.5 m L/g).With the decrease of bentonite dosage from1.5wt%to 1.0wt%,the drop number of green pellets from a height of 0.5 m and the compressive strengths of roasted pellets using the modified bentonite(6.0 times and 2916 N per pellet)were significantly higher than those of the original bentonite(4.0 times and 2739 N per pellet).This study provides a comprehensive analysis of the intercalation modification mechanism of bentonite,offering crucial technical insights for the development of high-performance modified bentonite as iron ore pellet binders.展开更多
Current studies on carbon nanotube (CNT) size effects predominantly employ Eringen’s differential nonlocal model, which is widely recognized as ill-suited for bounded domains. This paper investigates the free vibrati...Current studies on carbon nanotube (CNT) size effects predominantly employ Eringen’s differential nonlocal model, which is widely recognized as ill-suited for bounded domains. This paper investigates the free vibration of multi-walled CNTs (MWCNTs) with mathematically well-posed two-phase strain-driven and stress-driven nonlocal integral models incorporating the bi-Helmholtz kernel. The van der Waals (vdW) forces coupling MWCNT layers are similarly modeled as size-dependent via the bi-Helmholtz two-phase nonlocal integral framework. Critically, conventional pure strain-driven or stress-driven formulations become over-constrained when nonlocal vdW interactions are considered. The two-phase strategy resolves this limitation by enabling consistent coupling. Each bi-Helmholtz integral constitutive equation is equivalently transformed into a differential form requiring four additional constitutive boundary conditions (CBCs). The numerical solutions are obtained with the generalized differential quadrature method (GDQM) for these coupled higher-order equations. The parametric studies on double-walled CNTs (DWCNTs) and triple-walled CNTs (TWCNTs) elucidate the nonlocal effects predicted by both formulations. Additionally, the influence of nonlocal parameters within vdW forces is systematically evaluated to comprehensively characterize the size effects in MWCNTs.展开更多
基金financially supported by the National Natural Science Foundation of China(Nos.92160301,92060203,52175415 and 52205475)the Science Center for Gas Turbine Project(Nos.P2022-AB-Ⅳ-002-001 and P2023-B-Ⅳ-003-001)+3 种基金the Jiangsu Key Laboratory of Precision and Micro-Manufacturing Technology(No.JSKL2223K01)the Natural Science Foundation of Jiangsu Province(No.BK20210295)the Superior Postdoctoral Project of Jiangsu Province(No.2022ZB215)the Henan Science and Technology Public Relations Project(No.212102210445).
文摘The undeformed chip thickness and grinding force are key parameters for revealing the material removal mechanism in the grinding process.However,they are difficult to be well expressed due to the ununiformed protrusion height and random position distribution of abrasive grains on the abrasive wheel surface.This study investigated the distribution of undeformed chip thickness and grinding force considering the non-uniform characteristics of abrasive wheel in the grinding of K4002 nickel-based superalloy.First,a novel grinding force model was established through a kinematic-geometric analysis and a grain-workpiece contact analysis.Then,a series of grinding experiments were conducted for verifying the model.The results indicate that the distribution of undeformed chip thickness is highly consistent with the Gaussian distribution formula.The increase in the grinding depth mainly leads to an increase in the average value of Gaussian distribution.On the contrary,the increase in the workpiece infeed speed or the decrease in the grinding speed mainly increases the standard deviation of Gaussian distribution.The average and maximum errors of the grinding force model are 4.9%and 14.6%respectively,indicating that the model is of high predication accuracy.
基金supported by Natural Science Foundation of China(52178441)the Scientific Research Projects of the China Academy of Railway Sciences Co.,Ltd.(Grant No.2022YJ043).
文摘Rail weld irregularities are one of the primary excitation sources for vehicle-track interaction dynamics in modern high-speed railways.They can cause significant wheel-rail dynamic interactions,leading to wheel-rail noise,component damage,and deterioration.Few researchers have employed the vehicle-track interaction dynamic model to study the dynamic interactions between wheel and rail induced by rail weld geometry irregularities.However,the cosine wave model used to simulate rail weld irregularities mainly focuses on the maximum value and neglects the geometric shape.In this study,novel theoretical models were developed for three categories of rail weld irregularities,based on measurements of the high-speed railway from Beijing to Shanghai.The vertical dynamic forces in the time and frequency domains were compared under different running speeds.These forces generated by the rail weld irregularities that were measured and modeled,respectively,were compared to validate the accuracy of the proposed model.Finally,based on the numerical study,the impact force due to rail weld irrregularity is modeled using an Artificial Neural Network(ANN),and the optimum combination of parameters for this model is found.The results showed that the proposed model provided a more accurate wheel/rail dynamic evaluation caused by rail weld irregularities than that established in the literature.The ANN model used in this paper can effectively predict the impact force due to rail weld irrregularity while reducing the computation time.
基金supported by the Ministry of Science and Higher Education of the Russian Federation(No.075-15-2024-535)。
文摘The purpose of this article is to provide,from the perspective of deformable solid mechanics,a correct justification for the expressions of all forces acting on the surface of a ferromagnetic material in a magnetic field,initiated only by this field.It is shown that the moment of force applied to any closed body surface S,corresponding to the asymmetric part TAof the stress tensor T(denoted as the force pA),balances the mass magnetic moment Lmagacting in the volume V bounded by the surface S.The emergence of the asymmetric part TAof the stress tensor arises as a consequence of a special case within the moment theory of elasticity,the use of which is necessary for accurately describing the behavior of a ferromagnetic material in a magnetic field.The force pa acts in a plane tangential to the surface S at any point,while,in addition to this force,the normal force pn also acts on the body surface.It is shown in the article that the latter force arises as a result of a jump in the normal component of the magnetic field strength appearing at the body surface,and its expression is defined by the mass' s(ponderomotive) magnetic forces Fmag.Usually,this force is introduced based on the Maxwell stress tensor,which is used in the classical electromagnetism to represent the interaction between electromagnetic forces and mechanical momentum.However,as we believe and justify this in the article,such an approach is unacceptable in deformable solid mechanics.
基金funded by grants from the General Project of the National Social Science Fund:“Research on the Interactive Mechanism of Migrant Workers Returning to Their Hometowns for Entrepreneurship and Rural Revitalization in the Major Labor Export Provinces”(20BJY136)General Project of Sichuan Provincial Philosophy and Social Science Fund:“The Era Significance,Growth Constraints,and Path Optimization of the New Agricultural Laborers from the Perspective of the New Quality Productive Forces”(SCJJ24ND065)Key Project of the Sichuan Academy of Social Sciences:“The Era Significance,Current Concerns,and Action Prospects of the New Agricultural Laborers from the Perspective of the New Quality Productive Forces”(24XD02).
文摘Driven by technological innovation and the innovative allocation of production factors,new quality productive forces(NQPFs)are a key breakthrough and core element propelling China’s transition from a major agricultural country to an advanced agricultural nation.At its core,agricultural modernization represents a frontier shift in agricultural development-a dynamic evolution of productive forces across technological forms,farmer demographics,industrial structures,and urban-rural relations.NQPFs drive the high-quality,integrated development of agricultural modernization through agricultural technological innovation,green and low-carbon practices,and the enhancement of all production factors.As NQPFs evolve and agricultural modernization advances,we must address constraints stemming from gaps in technology,models,resources,and talent.Furthermore,we must foster deep integration among industry,research,and education to develop new pathways for industrial upgrading,promote green and efficient agricultural development,and bridge existing technological gaps.These collective efforts are crucial for accelerating the high-quality development of agricultural modernization.
文摘Nature is really powerful!Big earthquakes can make tall buildings and even whole mountains fall down.At Niagara Falls,waterfalls like crazy,filling 50 Olympic-sized pools in a minute!We know about storms like hurricanes and blizzards.But there are many other strange things nature can do that might surprise you!
基金Research on High-Quality Development Pathways for Vocational Human Resource Management Programs in Higher Vocational Education under the Perspective of Modernization(Project No.:SGYJG2024B02)。
文摘Higher vocational colleges are important institutions for cultivating skilled talents.With the development of new-quality productive forces,these colleges need to meet the requirements of digital transformation and improve the effectiveness of talent cultivation.In the process of higher vocational education,it is essential to emphasize teaching innovation and enhance the level of digital teaching.From the perspective of new-quality productive forces,this paper analyzes the new requirements put forward for higher vocational education and proposes specific digital transformation strategies.The purpose is to improve the effectiveness of talent cultivation and accumulate experience for the subsequent digital transformation of higher vocational education.
基金supported by the National Education Sciences Planning Program of China through the National Office for Education Sciences Planning(Grant No.DIA220376).
文摘The theory of new quality productive forces provides a foundational framework for cultivating pre-service English teachers.There is a high degree of consistency between the development of new quality productive forces and the cultivation of pre-service English teachers.The development of new quality productive forces has put forward new requirements for the cultivation of pre-service English teachers,while the cultivation of pre-service English teachers will also promote the development of new quality productive forces and provide talent support for it.Currently,the cultivation of pre-service English teachers faces numerous challenges,which requires strengthening top-level program design,reconstructing the curriculum system,expanding cultivation fields for pre-service English teachers,improving the digital literacy of pre-service English teachers,deepening international exchanges and cooperation,and building an evidence-based evaluation system as a guarantee to achieve new breakthroughs in the cultivation of pre-service English teachers and promote the development of new quality productive forces.
基金the State Key Laboratory of Deep Geotechnical Mechanics and Underground Engineering(SKLGDUEK2124)of China University of Mining and Technology(Beijing)for its support for this research。
文摘In the realm of slope monitoring and reinforcement,traditional prestressing anchor cables are extensively used.However,these conventional methods often face limitations when applied to loess slopes,such as potential issues with stress concentration and insufficient adaptability to the unique mechanical properties of loess,which may lead to challenges in ensuring long-term stability and effective reinforcement.Negative Poisson's ratio(NPR)anchor cables with constant resistance have emerged as a promising alternative,which can better match the engineering demands of loess slopes by providing more uniform stress distribution and adaptive deformation characteristics.The NPR cable's ability to maintain a constant resistance during deformation offers a distinct advantage over traditional methods as it can more effectively accommodate the complex and variable conditions of loess slopes.To investigate the anchoring performance of NPR cables in loess slope,the stress characteristics of NPR cable in loess medium were simulated and analysed by ABAQUS finite element software.First,static and general quasi-static analysis methods were used to simulate the NPR cable under static tensile conditions.The consistency of the simulated constant resistance deformation characteristics with experimental results found in the literature was verified.Second,the interaction model between the NPR cable coupled with the loess medium was established.Its constant resistance was calculated to be about 24.08%larger than that of NPR anchor cable while its plastic deformation was reduced by about 37.14%.The compressive stress on the contact surface between NPR cable and loess was concentrated near the free end of the sleeve,which indicated that the loess was prone to severe damage at the free end.The research results reveal the typical shear failure mechanism of NPR cable in loess medium,which provides an important theoretical basis for prevention of landslides and monitoring of loess slopes.
文摘Currently,driven by the accelerated iteration of digital technologies such as big data,cloud computing,and artificial intelligence,the digital economy has become a crucial engine for generating new quality productive forces and promoting industrial upgrading.Building on a systematic review of the theoretical evolution and measurement methods of the digital economy and new quality productive forces,this paper outlines their enabling mechanisms,industrial synergy pathways,and policy practices,and summarizes regional disparities and spatial spillover effects.The main findings are as follows:First,the digital economy reshapes the traditional factor structure and significantly enhances total factor productivity through the permeation of data elements and technological innovation;Second,driven jointly by the consumer internet and the industrial internet,it optimizes supply–demand matching and service models while reducing operating costs and improving production efficiency;Third,policy environments and institutional coordination amplify the enabling effects,as evidenced notably in national big-data pilot zones and the“East Data West Computing”initiative.Looking ahead,empirical research should deepen the exploration of micro-level mechanisms and dynamic panel analyses,construct a measurement system of new quality productive forces that spans macro,meso,and micro scales,and investigate pathways for regional collaborative governance and green digital integration to address the complex challenges of the new era.
基金Supported by the National Social Science Foundation Project"Research on the Theoretical Logic and Practical Path of the Cultural Mission of Ideological and Political Education in the New Era"(20XKS022).
文摘Digital technology is a pivotal factor in developing new quality productive forces in agriculture and building digital villages.Using digital technology as a foundation to explore viable methods for these forces is an imperative for realizing rural revitalization and fostering circular agricultural development.This paper outlines the theoretical logic of how new quality productive forces empower digital village construction,focusing on accelerating smart village initiatives,promoting rural digital production,and developing unique local resources.Based on the practical challenges currently facing digital village development,it formulates several countermeasures.These include stimulating rural industrial endogenous motivation through urban-rural industrial integration,implementing actions to enhance rural digital governance,building a contingent of rural digital talent,and improving rural digital infrastructure.The aim is to provide insights for better leveraging the dynamic role of new quality productive forces in promoting digital village construction.
文摘From the perspective of new productive forces,the general technology curriculum in senior high schools should not only cultivate students’technical knowledge and practical abilities but also focus on the development of innovative thinking to meet the demand for interdisciplinary talents in the future society.Based on the chapter“Common Conception Methods”in the Jiangsu Education Edition of Technology and Design 1,this paper explores the implementation path of the general technology curriculum,focusing on the optimization strategies in four aspects:Project-based learning(PBL),strengthening technical practice,STEAM interdisciplinary integration,and a diversified.evaluation system It also analyzes the application of divergent thinking(brainstorming)and reverse thinking in the curriculum through cases.The research shows that optimizing teaching methods and enhancing practical links can effectively stimulate students’creativity and teamwork ability,improve the effectiveness of curriculum implementation,and provide strong support for the cultivation of future technical innovation talents.
基金funded by Research on Policy Design and Implementation Path for High-Quality Development of Digital Cultural Industry(23&ZD087),a major project of the National Social Science Foundation of China.
文摘Digital-intelligent technologies represent the advanced direction of new quality productive forces and are becoming a driving force for the digital transformation and high-quality development of the cultural industry.Empowered by new quality productive forces,the digital cultural industry has demonstrated diverse characteristics,including the innovation of cultural production subjects,the intelligentization of production tools,the digitization of production objects,the systematization of production methods,and the diversification of production factors.Leveraging technologies such as AIGC,virtual-physical integration,and DAOs based on Web 3.0,the digital cultural industry has established an innovative paradigm,fostering a new method of AIGC production in the digital cultural industry,a new business format of virtual-physical integration,and a new collaborative ecosystem characterized by co-creation,co-building,and co-governance.Meanwhile,the innovative paradigm of the digital cultural industry also faces a series of new challenges,such as the adaptability issues with AIGC algorithm models,creative bottlenecks,and content quality control problems.Additionally,there are obstacles like the immaturity of international development channels for new business formats,the lack of cultural connotations in creative products,and the lag of the digital-intelligent governance of the industry ecosystem behind digital practices.In light of this,there is an urgent need to establish an optimization mechanism for the high-quality development of digital cultural industries driven by new quality productive forces.This includes optimizing the content production mechanism for AIGC-led high-quality innovation in the digital cultural industry;improving the leapfrog development mechanism for new digital cultural business formats through global-regional collaboration;and enhancing the accurate,high-quality governance mechanism for the digital cultural industry that is aligned with the goals of Chinese modernization.
基金funded by the Ministry of Education’s Humanities and Social Sciences Research Planning Project(23YJA790070).
文摘Sustainable development,underpinned by robust systemic driving forces,is central to the growth of high-quality tourism.Therefore,identifying these forces at the regional level is crucial for advancing China’s goal of becoming a leading nation for tourism.This study accordingly constructs a new evaluation system that covers tourism market demand,industry supply,and structural transformation,and analyzes data from 31 Chinese provincial regions(2010–2019).The entropy method and spatial autocorrelation analysis were applied to examine the driving forces for sustainable regional tourism development.The results revealed that:First,at the national level,the driving forces for sustainable regional tourism development exhibited a clear upward trend from 2010 to 2019,with an acceleration in growth after 2015.However,there was significant regional heterogeneity:The eastern region displayed the highest levels of driving forces,followed by the central and western regions.Second,high-value clusters of these driving forces expanded from the eastern to the western regions,while the central provinces remained relatively balanced.Specifically,provincial regions such as Guangdong,Beijing,and Zhejiang were able to successively enter the high-value clusters,whereas the Xinjiang Uygur autonomous region,Gansu,and Qinghai consistently remained in the low-value clusters.Third,the driving forces exhibited a significant spatial agglomeration effect.The degree of clustering followed an inverted“U”trend over the study period,while the spatial patterns of the provincial regions remained relatively stable.
基金The Third Scientific Expedition Project in Xinjiang,No.2022xjkk0905Project Commissioned by the General Administration of Sport of ChinaProject Commissioned by the Ministry of Culture and Tourism of the People’s Republic of China。
文摘This study proposes a framework for the concept of“new quality productive forces”in the ice and snow economy(ISE)as a strategic response to global climate change and the demands of technological and industrial transformation for high-quality development.These new quality productive forces in the ISE have developed alongside the zonal distribution of natural resources,strictly adhere to ecological principles,and integrate value transformation mechanisms specific to ice and snow resources.Their development is projected to generate multiple benefits across ecological,economic,and social dimensions.The new quality productive forces in the ISE are characterized by technology-driven resource development,synergistic integration across the entire ice and snow industry value chain,and a focus on high-quality,green growth.Grounded in geography and economics,the new quality productive forces in the ISE link scientific innovation,the reallocation of productive factors,and industrial upgrading within the context of resource constraints.Furthermore,they expand the growth potential of the ISE by fostering new production relations through digital,intelligent,and green integration,while advancing low-carbon,sustainable development under the guiding principle that“ice and snow landscapes are also mountains of gold and silver.”For China's ISE,these new quality productive forces emphasize rigorous resource protection,balanced human-environment relationships,a resilient integrated supply chain framework,and an efficient“dual circulation”economic model.Practical strategies include integrating production factors,optimizing spatial resource allocation,fostering industrial synergy,and adapting production relations,all aimed at advancing the sustainable and high-quality development of China's ISE.
基金supported by the National Nature Science Foundation of China(Grant No.32171305)Chongqing Technology Innova-tion and Application Development Project(Grant No.CSTB2023YSZX-JSX0003)Chongqing Municipal“Doctoral Express”Research Project(Grant No.CSTB2022BSXM-JCX0013).
文摘Head injuries from vehicle collisions,falls,and sports are often the result of complex mechanisms involving both linear and angular forces.This study aims to quantitatively assess the effects of linear and angular force on the severity of traumatic brain injury in rats during collisions.An orthogonal experimental design was employed,facilitating the manipulation of linear velocity,rotational acceleration,and angle(light,medium,and heavy)across 54 rats.24 hours post-injury,magnetic resonance imaging T2-weighted imaging,and diffusion tensor imaging were utilized to detect abnormal brain signals,with the fractional anisotropy value of the corpus callosum serv-ing as the primary injury indicator.Anatomical analyses and immunohistological staining were conducted to measure the amyloid precursor protein(β-APP)accumulation,using integrated optical density as a secondary indicator.Entropy weighting was applied to derive index weights for the injury scoring system.Through analysis guided by analysis of variance and linear regression,it was determined that both linear and angular loadings significantly impacted brain injury severity.Increased rotational acceleration at constant linear velocities correlated with more severe injuries,whereas the rotation angle exhibited minimal effect.Linear velocity emerged as the primary determinant of injury severity,accounting for 91.5%of the variance,while rotational acceleration and rotation angle contributed 6.5%and 0.9%,respectively.These findings offer critical insights for developing protective measures against brain injuries in traffic accidents.
基金financial support by the National Key Research and Development Program of China(No.2023YFC2907801)the Hunan Provincial Natural Science Foundation of China(No.2023JJ40760)the Scientific and Technological Project of Yunnan Precious Metals Laboratory,China(No.YPML-2023050276)。
文摘Bentonite is a necessary binder in producing pellets.Its excessive use reduces the iron grade of pellets and increases production costs.Minimizing bentonite dosage is essential for producing high-quality iron ore pellets.Addressing the gap in the application of organically-intercalated modified bentonite in the pelletizing field,this study introduces an innovative modification process for bentonite that employs the synergistic effect of mechanical force and dimethyl sulfoxide to enhance the intercalation of organic compounds within bentonite,thus significantly enhancing its binding performance.The colloid value and swell capacity of modified bentonite(98.5 m L/3g and 55.0 m L/g)were much higher than the original bentonite(90.5 m L/3g and 17.5 m L/g).With the decrease of bentonite dosage from1.5wt%to 1.0wt%,the drop number of green pellets from a height of 0.5 m and the compressive strengths of roasted pellets using the modified bentonite(6.0 times and 2916 N per pellet)were significantly higher than those of the original bentonite(4.0 times and 2739 N per pellet).This study provides a comprehensive analysis of the intercalation modification mechanism of bentonite,offering crucial technical insights for the development of high-performance modified bentonite as iron ore pellet binders.
基金Project supported by the National Natural Science Foundation of China(Nos.12172169 and 12272064)the Natural Science Foundation of Jiangsu Province of China(No.BK20241773)the Priority Academic Program Development of Jiangsu Higher Education Institutions of China。
文摘Current studies on carbon nanotube (CNT) size effects predominantly employ Eringen’s differential nonlocal model, which is widely recognized as ill-suited for bounded domains. This paper investigates the free vibration of multi-walled CNTs (MWCNTs) with mathematically well-posed two-phase strain-driven and stress-driven nonlocal integral models incorporating the bi-Helmholtz kernel. The van der Waals (vdW) forces coupling MWCNT layers are similarly modeled as size-dependent via the bi-Helmholtz two-phase nonlocal integral framework. Critically, conventional pure strain-driven or stress-driven formulations become over-constrained when nonlocal vdW interactions are considered. The two-phase strategy resolves this limitation by enabling consistent coupling. Each bi-Helmholtz integral constitutive equation is equivalently transformed into a differential form requiring four additional constitutive boundary conditions (CBCs). The numerical solutions are obtained with the generalized differential quadrature method (GDQM) for these coupled higher-order equations. The parametric studies on double-walled CNTs (DWCNTs) and triple-walled CNTs (TWCNTs) elucidate the nonlocal effects predicted by both formulations. Additionally, the influence of nonlocal parameters within vdW forces is systematically evaluated to comprehensively characterize the size effects in MWCNTs.
