Cross-border e-commerce has emerged as a new growth point in foreign trade.While the Dalian comprehensive pilot zone has made some progress,its development is constrained by issues such as the global economic slowdown...Cross-border e-commerce has emerged as a new growth point in foreign trade.While the Dalian comprehensive pilot zone has made some progress,its development is constrained by issues such as the global economic slowdown,the relatively small scale of cross-border e-commerce,a high concentration of export commodities,imperfect information mechanisms,and high overall costs.To address these challenges,this paper explores the importance of the construction of the Dalian comprehensive pilot zone for cross-border e-commerce to the transformation and upgrading of exports.Based on my research project,“Research on Path Optimization of Financial Support for the Development of Advanced Manufacturing Clusters in Dalian,”this paper analyzes the current challenges and limiting factors and proposes corresponding countermeasures and suggestions.展开更多
Oil-fired construction machinery(OCM)is a major source of urban air pollutants and CO_(2) emissions,and elec-trification is a crucial pathway for improving air quality and achieving China’s dual carbon goals;however,...Oil-fired construction machinery(OCM)is a major source of urban air pollutants and CO_(2) emissions,and elec-trification is a crucial pathway for improving air quality and achieving China’s dual carbon goals;however,its feasibility has not been fully explored.This study uses data envelopment analysis and the analytic hierarchy process to establish a development potential index,covering technical efficiency,economic cost,application sce-narios,and charging time and range,with an empirical analysis conducted in Beijing.The findings indicated the high feasibility of replacing OCM with electric alternatives,especially within the low-power range.Based on 2023 registered coding dat1,it is projected that by 2030,electrification could reduce regional average con-centrations of CO,NO_(x),PM_(2.5) and VOCs by 12.2%to 56.4%and reduce CO_(2) by 11.7%to 56.9%.Owing to economic considerations,small-and medium-sized machinery are particularly feasible for electrification.Key recommendations include prioritizing the electrification of forklifts,lifting platforms,and small-sized machinery in high-emission areas,particularly in central urban districts.Policies such as carbon taxes,carbon markets,and performance grading systems are suggested to incentivize electrification,along with expanding high-emission restriction zones and improving energy infrastructure to support widespread electrification.展开更多
To advance intelligent construction,standards must come first.The Ministry of Housing and Urban-Rural Development has issued the List for Replicable Experience and Practices for Developing Intelligent Construction fou...To advance intelligent construction,standards must come first.The Ministry of Housing and Urban-Rural Development has issued the List for Replicable Experience and Practices for Developing Intelligent Construction four times successively and the Technical Guidelines for Intelligent Construction(Trial).展开更多
E-commerce systems for construction material procurement are becoming increasingly important in Hong Kong. These E-commerce systems are non-interoperable and create problems for the buyers who use these systems to pur...E-commerce systems for construction material procurement are becoming increasingly important in Hong Kong. These E-commerce systems are non-interoperable and create problems for the buyers who use these systems to purchase construction materials. This paper presents the mobile agent-based approach and Web services-based approach for enabling interoperation of these systems in the E-Union environment.展开更多
The function of E-commerce is becoming more and more widely applied to many fields,which bring about some new challenges and opportunities for the construction of marketing model.It is proved that the more E-com- merc...The function of E-commerce is becoming more and more widely applied to many fields,which bring about some new challenges and opportunities for the construction of marketing model.It is proved that the more E-com- merce applied to the construction of marketing,the more precision of forecast for the enterprises can acquire,which is very helpful for the production and marketing of enterprises.Therefore,the research on the E-commerce applied to the construction of marketing is popular today.This paper applie...展开更多
Based on the background of big data era, vocational college education should keep pace with the times, clarify the development prospects of the industry under the digital economy, optimize the teaching system dependin...Based on the background of big data era, vocational college education should keep pace with the times, clarify the development prospects of the industry under the digital economy, optimize the teaching system depending on the needs of enterprises, make education and teaching comprehensive and forward-looking, and cultivate practical talents depending on the development of the times. In the teaching and research work, teachers should comprehensively consider the characteristics of talents, teaching objectives and other factors, timely adjust the teaching plan and talent training mode, and export high-quality talents for the society.展开更多
Cross-border e-commerce has progressively evolved with the deepening of economic globalization,and it now holds a significant place in the field of e-commerce.However,due to China’s late entry into the international ...Cross-border e-commerce has progressively evolved with the deepening of economic globalization,and it now holds a significant place in the field of e-commerce.However,due to China’s late entry into the international logistics supply chain,there are issues such as complex environment,uneven information technology,and disagreements on standards,resulting in certain cross-border e-commerce disadvantages in China.Therefore,in this context,this study analyzes the construction of international logistics supply chain management model from the perspective of cross-border e-commerce,so as to provide some reference for the development of China’s international logistics supply chain.展开更多
To fully leverage the advantages of mechanization and informatization in tunnel boring machine(TBM)operations,the authors aim to promote the advancement of tunnel construction technology toward intelligent development...To fully leverage the advantages of mechanization and informatization in tunnel boring machine(TBM)operations,the authors aim to promote the advancement of tunnel construction technology toward intelligent development.This involved exploring the deep integration of next-generation artificial intelligence technologies,such as sensing technology,automatic control technology,big data technology,deep learning,and machine vision,with key operational processes,including TBM excavation,direction adjustment,step changes,inverted arch block assembly,material transportation,and operation status assurance.The results of this integration are summarized as follows.(1)TBM key excavation parameter prediction algorithm was developed with an accuracy rate exceeding 90%.The TBM intelligent step-change control algorithm,based on machine vision,achieved an image segmentation accuracy rate of 95%and gripper shoe positioning error of±5 mm.(2)An automatic positioning system for inverted arch blocks was developed,enabling real-time perception of the spatial position and deviation during the assembly process.The system maintains an elevation positioning deviation within±3 mm and a horizontal positioning deviation within±10 mm,reducing the number of surveyors in each work team.(3)A TBM intelligent rail transportation system that achieves real-time human-machine positioning,automatic switch opening and closing,automatic obstacle avoidance,intelligent transportation planning,and integrated scheduling and command was designed.Each locomotive formation reduces one shunter and improves comprehensive transportation efficiency by more than 20%.(4)Intelligent analysis and prediction algorithms were developed to monitor and predict the trends of the hydraulic and gear oil parameters in real time,enhancing the proactive maintenance and system reliability.展开更多
The integration of the digital economy with the traditional sales industry has prompted the robust growth of e-commerce.Live-streaming e-commerce,as a novel business model,has gained immense popularity.However,is⁃sues...The integration of the digital economy with the traditional sales industry has prompted the robust growth of e-commerce.Live-streaming e-commerce,as a novel business model,has gained immense popularity.However,is⁃sues of regulatory loopholes and inefficacy continue to surface.In live-streaming e-commerce,the head anchor,as host of the live-streaming rooms,wields significant influence in determining the goods to be showcased and marketed.Such influence expands risks such as infringement of intellectual property rights.Yet the uncertainty in law concerning the identity of head anchors results in a lack of accountability.Current norms are inadequate in constraining the group of head anchors.Drawing on the principles of risk control,the alignment between benefit and risk,and the theory of so⁃cial cost control,this paper argues that it is both justifiable and feasible to impose a duty to exercise reasonable care on head anchors.To effectively enshrine this duty in law,it is of great importance to redefine the mechanism of identifying the duty of care of head anchors in live-streaming e-commerce.In particular,the contents of the duty of care under⁃taken by head anchors and the consequences of breaching such a duty of care should be clarified.展开更多
Cross-border e-commerce,as a new form of international trade,has shown great development potential in the context of the“Belt and Road”initiative.Based on the cross-border e-commerce export data from 2015 to 2024,th...Cross-border e-commerce,as a new form of international trade,has shown great development potential in the context of the“Belt and Road”initiative.Based on the cross-border e-commerce export data from 2015 to 2024,this paper analyzes the influencing factors of China's cross-border e-commerce exports to countries along the“Belt and Road”by constructing an econometric model.The study found that factors such as the perfection of digital infrastructure,the efficiency of logistics and transportation,the convenience of payment and settlement,and the penetration rate of consumers online shopping significantly affect the export scale of cross-border e-commerce.Institutional factors such as the development level of e-commerce platforms in countries along the route,market access thresholds,and tariff policies also play an important role.Based on the research results,suggestions are put forward to strengthen the construction of cross-border payment system,optimize the logistics distribution network,promote customs clearance facilitation,and deepen cooperation in the field of e-commerce,to provide references for promoting the development of China's crossborder e-commerce exports to countries along the“Belt and Road.”展开更多
Zeolite-loaded noble metal catalysts have demonstrated excellent performance in addressing cold-start automotive exhaust NOx emissions and catalytic oxidation of VOCs applications.Pd and Pt are the most commonly used ...Zeolite-loaded noble metal catalysts have demonstrated excellent performance in addressing cold-start automotive exhaust NOx emissions and catalytic oxidation of VOCs applications.Pd and Pt are the most commonly used active metals in PNA and VOC catalysts,respectively.However,despite the same metal/zeolite composition,the efficient active sites for PNA and VOC catalysts have been viewed as mainly Pd^(2+) and Pt^(0),respectively,both of which are different from each other.As a result,various methods need to be applied to dope Pd and Pt in zeolitic support respectively for different usages.No matter which type of metal species is needed,the common requirement for both PNA and VOC catalysts is that the metal species should be highly dispersed in zeolite support and stay stable.The purpose of this paper is to review the progress of synthetic means of zeolite-coated noble metals(Pd,Pt,etc.)as effective PNA or VOC catalysts.To give a better understanding of the relationship between efficient metal species and the introduced methods,the species that contributed to the NOx adsorption(PNA)and VOCs deep catalytic oxidation were first summarized and compared.Then,based on the above discussion,the detailed construction strategies for different active sites in PNA and VOC catalysts,respectively,were elaborated in terms of synthetic routes,precursor selection,and zeolite carrier requirements.It is hoped that this will contribute to a better understanding of noble metal adsorption/catalysis in zeolites and provide promising strategies for the design of adsorption/catalysts with high activity,selectivity and stability.展开更多
Construction engineering and management(CEM)has become increasingly complicated with the increasing size of engineering projects under different construction environments,motivating the digital transformation of CEM.T...Construction engineering and management(CEM)has become increasingly complicated with the increasing size of engineering projects under different construction environments,motivating the digital transformation of CEM.To contribute to a better understanding of the state of the art of smart techniques for engineering projects,this paper provides a comprehensive review of multi-criteria decision-making(MCDM)techniques,intelligent techniques,and their applications in CEM.First,a comprehensive framework detailing smart technologies for construction projects is developed.Next,the characteristics of CEM are summarized.A bibliometric review is then conducted to investigate the keywords,journals,and clusters related to the application of smart techniques in CEM during 2000-2022.Recent advancements in intelligent techniques are also discussed under the following six topics:①big data technology;②computer vision;③speech recognition;④natural language processing;⑤machine learning;and⑥knowledge representation,understanding,and reasoning.The applications of smart techniques are then illustrated via underground space exploitation.Finally,future research directions for the sustainable development of smart construction are highlighted.展开更多
The advent of parametric design has resulted in a marked increase in the complexity of building.Unfortunately,traditional construction methods make it difficult to meet the needs.Therefore,construction robots have bec...The advent of parametric design has resulted in a marked increase in the complexity of building.Unfortunately,traditional construction methods make it difficult to meet the needs.Therefore,construction robots have become a pivotal production tool in this context.Since the arm span of a single robot usually does not exceed 3 meters,it is not competent for producing large-scale building components.Accordingly,the extension of the robot,s working range is often achieved by external axes.Nevertheless,the coupling control of external axes and robots and their kinematic solution have become key challenges.The primary technical difficulties include customized construction robots,automatic solutions for external axes,fixed axis joints,and specific motion mode control.This paper proposes solutions to these difficulties,introduces the relevant basic concepts and algorithms in detail,and encapsulates these robotics principles and algorithm processes into the Grasshopper plug-in commonly used by architects to form the FURobot software platform.This platform effectively solves the above problems,lowers the threshold for architects,and improves production efficiency.The effectiveness of the algorithm and software in this paper is verified through simulation experiments.展开更多
Scientific and technological advancements are rapidly transforming underground engineering,shifting from labor-intensive,time-consuming methods to automated,real-time systems.This timely and comprehensive review cover...Scientific and technological advancements are rapidly transforming underground engineering,shifting from labor-intensive,time-consuming methods to automated,real-time systems.This timely and comprehensive review covers in-situ testing,intelligent monitoring,and geophysical testing methods,highlighting fundamental principles,testing apparatuses,data processing techniques,and engineering applications.The state-of-the-art summary emphasizes not only cutting-edge innovations for complex and harsh environments but also the transformative role of artificial intelligence and machine learning in data interpretations.The integration of big data and advanced algorithms is particularly impactful,enabling the identification,prediction,and mitigation of potential risks in underground projects.Key aspects of the discussion include detection capabilities,method integration,and data convergence of intelligent technologies to drive enhanced safety,operational efficiency,and predictive reliability.The review also examines future trends in intelligent technologies,emphasizing unified platforms that combine multiple methods,real-time data,and predictive analytics.These advancements are shaping the evolution of underground construction and maintenance,aiming for risk-free,high-efficiency underground engineering.展开更多
To understand the smoke level and NO_(x)emission characteristics of in-use construction machinery in Beijing,we selected 905 construction machines in Beijing from August 2022 to April 2023 to monitor the emission leve...To understand the smoke level and NO_(x)emission characteristics of in-use construction machinery in Beijing,we selected 905 construction machines in Beijing from August 2022 to April 2023 to monitor the emission level of smoke and NO_(x).The exhaust smoke level and excessive emission situation of different machinery types were identified,and their NO_(x)emission levels were monitored according to the free acceleration method.We investigated the correlation of NO_(x)and smoke emission,and proposed suggestions for controlling pollution discharge from construction machinery in the future.The results show that the exhaust smoke level was 0–2.62 m^(−1),followed a log-normal distribution(μ=-1.73,δ=1.09,R^(2)=0.99),with a 5.64%exceedance rate.Differenceswere observed amongmachinery types,with low-power engine forklifts showing higher smoke levels.The NO_(x)emission range was 71–1516 ppm,followed a normal distribution(μ=565.54,δ=309.51,R^(2)=0.83).Differences among machinery types were relatively small.Engine rated net power had the most significant impact on NO_(x)emissions.Thus,NO_(x)emissions from construction machinery need further attention.Furthermore,we found a weak negative correlation(p<0.05)between the emission level of smoke and NO_(x),that is the synergic emission reduction effect is poor,emphasizing the need for NO_(x)emission limits.In the future,the oversight in Beijing should prioritize phasing out ChinaⅠand ChinaⅡmachinery,and monitor emissions from highpower engine ChinaⅢmachinery.展开更多
Interface chemical modulation strategies are considered as promising method to prepare electrocatalysts for the urea oxidation reaction(UOR).However,conventional interface catalysts are generally limited by the inhere...Interface chemical modulation strategies are considered as promising method to prepare electrocatalysts for the urea oxidation reaction(UOR).However,conventional interface catalysts are generally limited by the inherent activity and incompatibility of the individual components themselves,and the irregular charge distribution and slow charge transfer ability between interfaces severely limit the activity of UOR.Therefore,we optimized and designed a Ni_(2)P/CoP interface with modulated surface charge distribution and directed charge transfer to promote UOR activity.Density functional theorycalculations first predict a regular charge transfer from CoP to Ni_(2)P,which creates a built-in electric field between Ni_(2)P and CoP interface.Optimization of the adsorption/desorption process of UOR/HER reaction intermediates leads to the improvement of catalytic activity.Electrochemical impedance spectroscopy and ex situ X-ray photoelectron spectroscopy characterization confirm the unique mechanism of facilitated reaction at the Ni_(2)P/CoP interface.Electrochemical tests further validated the prediction with excellent UOR/HER activities of 1.28 V and 19.7 mV vs.RHE,at 10 mA cm^(-2),respectively.Furthermore,Ni_(2)P/CoP achieves industrial-grade current densities(500 mA cm^(−2))at 1.75 V and 1.87 V in the overall urea electrolyzer(UOR||HER)and overall human urine electrolyzer(HUOR||HER),respectively,and demonstrates considerable durability.展开更多
Scientifically understanding the evolution of urbanization and analysing the coupling mechanism of human-land systems are important foundations for solving spatial conflicts and promoting regional sustainable developm...Scientifically understanding the evolution of urbanization and analysing the coupling mechanism of human-land systems are important foundations for solving spatial conflicts and promoting regional sustainable development.This study analyzed the spatiotemporal evolution and landscape pattern change of construction land in the Yangtze River Delta(YRD)region from 1990 to 2018 by integrating Geographical Information System(GIS)spatial analysis and landscape pattern indices,and revealed its driving mechanism by XGBoost and SHapley Additive ex Planations(SHAP).Moreover,we compared the disparities in the core driving factors for construction land evolution in cities with diverse development orientations within the YRD region.Results show that:1)development intensity of construction land continued to increase from 7.54%in 1990 to 13.44%in 2018,primarily by occupying farmland.The landscape fragmentation of construction land in the YRD region decreased,and landscape dominance increased.Spatially,the eastern part of the YRD exhibits a high degree of spatial agglomeration of construction land,whereas the western part shows a high degree of fragmentation,revealing distinct spatial gradient differentiation characteristics.The landscape dominance of the construction land in the eastern region of the YRD is higher than that in the western and northern regions.2)Transportation and infrastructure exert the highest contribution rate on development intensity changes of construction land in the YRD.The industrial structure significantly influences the conversion of farmland to construction land.Additionally,infrastructure plays a crucial role in shaping the spatial agglomeration patterns of construction land.Population distribution is the dominant factor determining the regularity of the landscape shape of construction land.3)The core driving factors for the development intensity of construction land in central cities primarily lies in transportation,whereas for non-central cities,besides transportation,the year-end balance of per capita savings deposits of urban and rural residents also play a significant role.The area change of construction land occupying farmland in central and non-central cities is mainly driven by industrial structure and economic level,respectively.This study informs refined spatial optimization and regional high-quality integrated development.展开更多
With the rapid development of globalization and information technology,intellectual property has been one of the key drivers of economic growth,and the construction of intellectual property system has become an import...With the rapid development of globalization and information technology,intellectual property has been one of the key drivers of economic growth,and the construction of intellectual property system has become an important criterion for measuring the quality of business environment.This article is intended to explore the current status of intellectual property system construction in China,the challenges,and its relationship with the business environment,to propose the corresponding countermeasures and suggestions.The study finds that the legal system of intellectual property in China is gradually improving,and judicial and administrative protection are continuously strengthened.However,the challenges still remain such as frequent infringements,rights hard to protect and insufficient international cooperation.These issues not only affect the legitimate rights and interests of innovation entities,but also for the market fairness and the level of the business environment.Therefore,this article proposes that strengthening the perfection of the intellectual property legal system,enhancing intellectual property services and support capabilities,strengthening international cooperation and exchanges,and accelerating the cultivation of composite talents.It aims to provide theoretical references for the construction of intellectual property system and the optimization of the business environment,promote the high-quality development of economy and enhance the global competitiveness of the country.展开更多
The purpose of this study is to analyze factors affecting the purchasing behavior of low-income Vietnamese on e-commerce platforms.700 questionnaires were dispersed among universities,coffee shops,and Facebook communi...The purpose of this study is to analyze factors affecting the purchasing behavior of low-income Vietnamese on e-commerce platforms.700 questionnaires were dispersed among universities,coffee shops,and Facebook community groups in Vietnam.Respondents to the questionnaires were consumers of those places in Vietnam,which were randomly selected.Finally,SEM analysis was used on the data to test the hypotheses of the study.The study identified that“Subjective norms”and“Consumer attitudes”have no effect on shopping behavior on e-commerce platforms,while“Perceived behavioral control”is most affected and“Perceived risks”are least affected on shopping behavior.展开更多
This paper systematically reviews the development trajectory of rural e-commerce in China from the late 1990s to the present,categorizing it into three distinct phases:the embryonic stage,the growth stage,and the boom...This paper systematically reviews the development trajectory of rural e-commerce in China from the late 1990s to the present,categorizing it into three distinct phases:the embryonic stage,the growth stage,and the boom stage.It elaborates on the evolutionary process through which rural e-commerce,propelled by strong policy support,driven by market demand,and facilitated by infrastructure improvements,has progressed from providing information services to becoming a pivotal force in advancing rural revitalization.The paper summarizes governmental support measures encompassing policies,training,and logistics,while also conducting an in-depth analysis of the current challenges and opportunities,including infrastructure limitations,market competition,the digital divide,and the application of AI technologies.展开更多
文摘Cross-border e-commerce has emerged as a new growth point in foreign trade.While the Dalian comprehensive pilot zone has made some progress,its development is constrained by issues such as the global economic slowdown,the relatively small scale of cross-border e-commerce,a high concentration of export commodities,imperfect information mechanisms,and high overall costs.To address these challenges,this paper explores the importance of the construction of the Dalian comprehensive pilot zone for cross-border e-commerce to the transformation and upgrading of exports.Based on my research project,“Research on Path Optimization of Financial Support for the Development of Advanced Manufacturing Clusters in Dalian,”this paper analyzes the current challenges and limiting factors and proposes corresponding countermeasures and suggestions.
基金supported by the National Science and Technology Major Project of the Ministry of Science and Technology of China(No.2024ZD1200200).
文摘Oil-fired construction machinery(OCM)is a major source of urban air pollutants and CO_(2) emissions,and elec-trification is a crucial pathway for improving air quality and achieving China’s dual carbon goals;however,its feasibility has not been fully explored.This study uses data envelopment analysis and the analytic hierarchy process to establish a development potential index,covering technical efficiency,economic cost,application sce-narios,and charging time and range,with an empirical analysis conducted in Beijing.The findings indicated the high feasibility of replacing OCM with electric alternatives,especially within the low-power range.Based on 2023 registered coding dat1,it is projected that by 2030,electrification could reduce regional average con-centrations of CO,NO_(x),PM_(2.5) and VOCs by 12.2%to 56.4%and reduce CO_(2) by 11.7%to 56.9%.Owing to economic considerations,small-and medium-sized machinery are particularly feasible for electrification.Key recommendations include prioritizing the electrification of forklifts,lifting platforms,and small-sized machinery in high-emission areas,particularly in central urban districts.Policies such as carbon taxes,carbon markets,and performance grading systems are suggested to incentivize electrification,along with expanding high-emission restriction zones and improving energy infrastructure to support widespread electrification.
文摘To advance intelligent construction,standards must come first.The Ministry of Housing and Urban-Rural Development has issued the List for Replicable Experience and Practices for Developing Intelligent Construction four times successively and the Technical Guidelines for Intelligent Construction(Trial).
文摘E-commerce systems for construction material procurement are becoming increasingly important in Hong Kong. These E-commerce systems are non-interoperable and create problems for the buyers who use these systems to purchase construction materials. This paper presents the mobile agent-based approach and Web services-based approach for enabling interoperation of these systems in the E-Union environment.
基金This research was supported by the National Social Sci-ence Foundation of China under Grant 06CJL019.
文摘The function of E-commerce is becoming more and more widely applied to many fields,which bring about some new challenges and opportunities for the construction of marketing model.It is proved that the more E-com- merce applied to the construction of marketing,the more precision of forecast for the enterprises can acquire,which is very helpful for the production and marketing of enterprises.Therefore,the research on the E-commerce applied to the construction of marketing is popular today.This paper applie...
文摘Based on the background of big data era, vocational college education should keep pace with the times, clarify the development prospects of the industry under the digital economy, optimize the teaching system depending on the needs of enterprises, make education and teaching comprehensive and forward-looking, and cultivate practical talents depending on the development of the times. In the teaching and research work, teachers should comprehensively consider the characteristics of talents, teaching objectives and other factors, timely adjust the teaching plan and talent training mode, and export high-quality talents for the society.
文摘Cross-border e-commerce has progressively evolved with the deepening of economic globalization,and it now holds a significant place in the field of e-commerce.However,due to China’s late entry into the international logistics supply chain,there are issues such as complex environment,uneven information technology,and disagreements on standards,resulting in certain cross-border e-commerce disadvantages in China.Therefore,in this context,this study analyzes the construction of international logistics supply chain management model from the perspective of cross-border e-commerce,so as to provide some reference for the development of China’s international logistics supply chain.
文摘To fully leverage the advantages of mechanization and informatization in tunnel boring machine(TBM)operations,the authors aim to promote the advancement of tunnel construction technology toward intelligent development.This involved exploring the deep integration of next-generation artificial intelligence technologies,such as sensing technology,automatic control technology,big data technology,deep learning,and machine vision,with key operational processes,including TBM excavation,direction adjustment,step changes,inverted arch block assembly,material transportation,and operation status assurance.The results of this integration are summarized as follows.(1)TBM key excavation parameter prediction algorithm was developed with an accuracy rate exceeding 90%.The TBM intelligent step-change control algorithm,based on machine vision,achieved an image segmentation accuracy rate of 95%and gripper shoe positioning error of±5 mm.(2)An automatic positioning system for inverted arch blocks was developed,enabling real-time perception of the spatial position and deviation during the assembly process.The system maintains an elevation positioning deviation within±3 mm and a horizontal positioning deviation within±10 mm,reducing the number of surveyors in each work team.(3)A TBM intelligent rail transportation system that achieves real-time human-machine positioning,automatic switch opening and closing,automatic obstacle avoidance,intelligent transportation planning,and integrated scheduling and command was designed.Each locomotive formation reduces one shunter and improves comprehensive transportation efficiency by more than 20%.(4)Intelligent analysis and prediction algorithms were developed to monitor and predict the trends of the hydraulic and gear oil parameters in real time,enhancing the proactive maintenance and system reliability.
文摘The integration of the digital economy with the traditional sales industry has prompted the robust growth of e-commerce.Live-streaming e-commerce,as a novel business model,has gained immense popularity.However,is⁃sues of regulatory loopholes and inefficacy continue to surface.In live-streaming e-commerce,the head anchor,as host of the live-streaming rooms,wields significant influence in determining the goods to be showcased and marketed.Such influence expands risks such as infringement of intellectual property rights.Yet the uncertainty in law concerning the identity of head anchors results in a lack of accountability.Current norms are inadequate in constraining the group of head anchors.Drawing on the principles of risk control,the alignment between benefit and risk,and the theory of so⁃cial cost control,this paper argues that it is both justifiable and feasible to impose a duty to exercise reasonable care on head anchors.To effectively enshrine this duty in law,it is of great importance to redefine the mechanism of identifying the duty of care of head anchors in live-streaming e-commerce.In particular,the contents of the duty of care under⁃taken by head anchors and the consequences of breaching such a duty of care should be clarified.
文摘Cross-border e-commerce,as a new form of international trade,has shown great development potential in the context of the“Belt and Road”initiative.Based on the cross-border e-commerce export data from 2015 to 2024,this paper analyzes the influencing factors of China's cross-border e-commerce exports to countries along the“Belt and Road”by constructing an econometric model.The study found that factors such as the perfection of digital infrastructure,the efficiency of logistics and transportation,the convenience of payment and settlement,and the penetration rate of consumers online shopping significantly affect the export scale of cross-border e-commerce.Institutional factors such as the development level of e-commerce platforms in countries along the route,market access thresholds,and tariff policies also play an important role.Based on the research results,suggestions are put forward to strengthen the construction of cross-border payment system,optimize the logistics distribution network,promote customs clearance facilitation,and deepen cooperation in the field of e-commerce,to provide references for promoting the development of China's crossborder e-commerce exports to countries along the“Belt and Road.”
基金supported by Zhongtian Iron and Steel-University of Science and Technology Beijing Youth Science and Technology Innovation Fund(No.FZTNTC2024050005)National Engineering Laboratory for Mobile Source Emission Control Technology,China(No.NELMS2020A07)The Fundamental Research Funds for the Central Universities,China(No.FRF-AT-20-12)。
文摘Zeolite-loaded noble metal catalysts have demonstrated excellent performance in addressing cold-start automotive exhaust NOx emissions and catalytic oxidation of VOCs applications.Pd and Pt are the most commonly used active metals in PNA and VOC catalysts,respectively.However,despite the same metal/zeolite composition,the efficient active sites for PNA and VOC catalysts have been viewed as mainly Pd^(2+) and Pt^(0),respectively,both of which are different from each other.As a result,various methods need to be applied to dope Pd and Pt in zeolitic support respectively for different usages.No matter which type of metal species is needed,the common requirement for both PNA and VOC catalysts is that the metal species should be highly dispersed in zeolite support and stay stable.The purpose of this paper is to review the progress of synthetic means of zeolite-coated noble metals(Pd,Pt,etc.)as effective PNA or VOC catalysts.To give a better understanding of the relationship between efficient metal species and the introduced methods,the species that contributed to the NOx adsorption(PNA)and VOCs deep catalytic oxidation were first summarized and compared.Then,based on the above discussion,the detailed construction strategies for different active sites in PNA and VOC catalysts,respectively,were elaborated in terms of synthetic routes,precursor selection,and zeolite carrier requirements.It is hoped that this will contribute to a better understanding of noble metal adsorption/catalysis in zeolites and provide promising strategies for the design of adsorption/catalysts with high activity,selectivity and stability.
基金funded by the project of Guangdong Provincial Basic and Applied Basic Research Fund Committee(2022A1515240073)the Pearl River Talent Recruitment Program(2019CX01G338),Guangdong Province.
文摘Construction engineering and management(CEM)has become increasingly complicated with the increasing size of engineering projects under different construction environments,motivating the digital transformation of CEM.To contribute to a better understanding of the state of the art of smart techniques for engineering projects,this paper provides a comprehensive review of multi-criteria decision-making(MCDM)techniques,intelligent techniques,and their applications in CEM.First,a comprehensive framework detailing smart technologies for construction projects is developed.Next,the characteristics of CEM are summarized.A bibliometric review is then conducted to investigate the keywords,journals,and clusters related to the application of smart techniques in CEM during 2000-2022.Recent advancements in intelligent techniques are also discussed under the following six topics:①big data technology;②computer vision;③speech recognition;④natural language processing;⑤machine learning;and⑥knowledge representation,understanding,and reasoning.The applications of smart techniques are then illustrated via underground space exploitation.Finally,future research directions for the sustainable development of smart construction are highlighted.
基金National Key R&D Program of China(Nos.2023YFC3806900,2022YFE0141400)。
文摘The advent of parametric design has resulted in a marked increase in the complexity of building.Unfortunately,traditional construction methods make it difficult to meet the needs.Therefore,construction robots have become a pivotal production tool in this context.Since the arm span of a single robot usually does not exceed 3 meters,it is not competent for producing large-scale building components.Accordingly,the extension of the robot,s working range is often achieved by external axes.Nevertheless,the coupling control of external axes and robots and their kinematic solution have become key challenges.The primary technical difficulties include customized construction robots,automatic solutions for external axes,fixed axis joints,and specific motion mode control.This paper proposes solutions to these difficulties,introduces the relevant basic concepts and algorithms in detail,and encapsulates these robotics principles and algorithm processes into the Grasshopper plug-in commonly used by architects to form the FURobot software platform.This platform effectively solves the above problems,lowers the threshold for architects,and improves production efficiency.The effectiveness of the algorithm and software in this paper is verified through simulation experiments.
基金supported by Ministry of Education of Singapore,under Academic Research Fund Tier 1(Grant Number RG143/23).
文摘Scientific and technological advancements are rapidly transforming underground engineering,shifting from labor-intensive,time-consuming methods to automated,real-time systems.This timely and comprehensive review covers in-situ testing,intelligent monitoring,and geophysical testing methods,highlighting fundamental principles,testing apparatuses,data processing techniques,and engineering applications.The state-of-the-art summary emphasizes not only cutting-edge innovations for complex and harsh environments but also the transformative role of artificial intelligence and machine learning in data interpretations.The integration of big data and advanced algorithms is particularly impactful,enabling the identification,prediction,and mitigation of potential risks in underground projects.Key aspects of the discussion include detection capabilities,method integration,and data convergence of intelligent technologies to drive enhanced safety,operational efficiency,and predictive reliability.The review also examines future trends in intelligent technologies,emphasizing unified platforms that combine multiple methods,real-time data,and predictive analytics.These advancements are shaping the evolution of underground construction and maintenance,aiming for risk-free,high-efficiency underground engineering.
基金supported by the Energy Foundation(No.G-2203-33693).
文摘To understand the smoke level and NO_(x)emission characteristics of in-use construction machinery in Beijing,we selected 905 construction machines in Beijing from August 2022 to April 2023 to monitor the emission level of smoke and NO_(x).The exhaust smoke level and excessive emission situation of different machinery types were identified,and their NO_(x)emission levels were monitored according to the free acceleration method.We investigated the correlation of NO_(x)and smoke emission,and proposed suggestions for controlling pollution discharge from construction machinery in the future.The results show that the exhaust smoke level was 0–2.62 m^(−1),followed a log-normal distribution(μ=-1.73,δ=1.09,R^(2)=0.99),with a 5.64%exceedance rate.Differenceswere observed amongmachinery types,with low-power engine forklifts showing higher smoke levels.The NO_(x)emission range was 71–1516 ppm,followed a normal distribution(μ=565.54,δ=309.51,R^(2)=0.83).Differences among machinery types were relatively small.Engine rated net power had the most significant impact on NO_(x)emissions.Thus,NO_(x)emissions from construction machinery need further attention.Furthermore,we found a weak negative correlation(p<0.05)between the emission level of smoke and NO_(x),that is the synergic emission reduction effect is poor,emphasizing the need for NO_(x)emission limits.In the future,the oversight in Beijing should prioritize phasing out ChinaⅠand ChinaⅡmachinery,and monitor emissions from highpower engine ChinaⅢmachinery.
文摘Interface chemical modulation strategies are considered as promising method to prepare electrocatalysts for the urea oxidation reaction(UOR).However,conventional interface catalysts are generally limited by the inherent activity and incompatibility of the individual components themselves,and the irregular charge distribution and slow charge transfer ability between interfaces severely limit the activity of UOR.Therefore,we optimized and designed a Ni_(2)P/CoP interface with modulated surface charge distribution and directed charge transfer to promote UOR activity.Density functional theorycalculations first predict a regular charge transfer from CoP to Ni_(2)P,which creates a built-in electric field between Ni_(2)P and CoP interface.Optimization of the adsorption/desorption process of UOR/HER reaction intermediates leads to the improvement of catalytic activity.Electrochemical impedance spectroscopy and ex situ X-ray photoelectron spectroscopy characterization confirm the unique mechanism of facilitated reaction at the Ni_(2)P/CoP interface.Electrochemical tests further validated the prediction with excellent UOR/HER activities of 1.28 V and 19.7 mV vs.RHE,at 10 mA cm^(-2),respectively.Furthermore,Ni_(2)P/CoP achieves industrial-grade current densities(500 mA cm^(−2))at 1.75 V and 1.87 V in the overall urea electrolyzer(UOR||HER)and overall human urine electrolyzer(HUOR||HER),respectively,and demonstrates considerable durability.
基金Under the auspices of the National Natural Science Foundation of China(No.42301470,42171389)。
文摘Scientifically understanding the evolution of urbanization and analysing the coupling mechanism of human-land systems are important foundations for solving spatial conflicts and promoting regional sustainable development.This study analyzed the spatiotemporal evolution and landscape pattern change of construction land in the Yangtze River Delta(YRD)region from 1990 to 2018 by integrating Geographical Information System(GIS)spatial analysis and landscape pattern indices,and revealed its driving mechanism by XGBoost and SHapley Additive ex Planations(SHAP).Moreover,we compared the disparities in the core driving factors for construction land evolution in cities with diverse development orientations within the YRD region.Results show that:1)development intensity of construction land continued to increase from 7.54%in 1990 to 13.44%in 2018,primarily by occupying farmland.The landscape fragmentation of construction land in the YRD region decreased,and landscape dominance increased.Spatially,the eastern part of the YRD exhibits a high degree of spatial agglomeration of construction land,whereas the western part shows a high degree of fragmentation,revealing distinct spatial gradient differentiation characteristics.The landscape dominance of the construction land in the eastern region of the YRD is higher than that in the western and northern regions.2)Transportation and infrastructure exert the highest contribution rate on development intensity changes of construction land in the YRD.The industrial structure significantly influences the conversion of farmland to construction land.Additionally,infrastructure plays a crucial role in shaping the spatial agglomeration patterns of construction land.Population distribution is the dominant factor determining the regularity of the landscape shape of construction land.3)The core driving factors for the development intensity of construction land in central cities primarily lies in transportation,whereas for non-central cities,besides transportation,the year-end balance of per capita savings deposits of urban and rural residents also play a significant role.The area change of construction land occupying farmland in central and non-central cities is mainly driven by industrial structure and economic level,respectively.This study informs refined spatial optimization and regional high-quality integrated development.
基金Guizhou Provincial University Humanities and Social Sciences Research Project in 2024"Enhancing the Development of New Productive Forces through University Technological Innovation and Intellectual Property Management"(2024RW256)Guizhou University of Commerce Research Project in 2022"Study on the Ideas and Pathways to Drive Agricultural Powerhouse through Digital Economy"(2022XJZX315)。
文摘With the rapid development of globalization and information technology,intellectual property has been one of the key drivers of economic growth,and the construction of intellectual property system has become an important criterion for measuring the quality of business environment.This article is intended to explore the current status of intellectual property system construction in China,the challenges,and its relationship with the business environment,to propose the corresponding countermeasures and suggestions.The study finds that the legal system of intellectual property in China is gradually improving,and judicial and administrative protection are continuously strengthened.However,the challenges still remain such as frequent infringements,rights hard to protect and insufficient international cooperation.These issues not only affect the legitimate rights and interests of innovation entities,but also for the market fairness and the level of the business environment.Therefore,this article proposes that strengthening the perfection of the intellectual property legal system,enhancing intellectual property services and support capabilities,strengthening international cooperation and exchanges,and accelerating the cultivation of composite talents.It aims to provide theoretical references for the construction of intellectual property system and the optimization of the business environment,promote the high-quality development of economy and enhance the global competitiveness of the country.
文摘The purpose of this study is to analyze factors affecting the purchasing behavior of low-income Vietnamese on e-commerce platforms.700 questionnaires were dispersed among universities,coffee shops,and Facebook community groups in Vietnam.Respondents to the questionnaires were consumers of those places in Vietnam,which were randomly selected.Finally,SEM analysis was used on the data to test the hypotheses of the study.The study identified that“Subjective norms”and“Consumer attitudes”have no effect on shopping behavior on e-commerce platforms,while“Perceived behavioral control”is most affected and“Perceived risks”are least affected on shopping behavior.
基金Supported by 2023 Key Discipline Construction Project of Zhejiang Open University:E-commerce Major(ZDZY202301).
文摘This paper systematically reviews the development trajectory of rural e-commerce in China from the late 1990s to the present,categorizing it into three distinct phases:the embryonic stage,the growth stage,and the boom stage.It elaborates on the evolutionary process through which rural e-commerce,propelled by strong policy support,driven by market demand,and facilitated by infrastructure improvements,has progressed from providing information services to becoming a pivotal force in advancing rural revitalization.The paper summarizes governmental support measures encompassing policies,training,and logistics,while also conducting an in-depth analysis of the current challenges and opportunities,including infrastructure limitations,market competition,the digital divide,and the application of AI technologies.
