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Asymmetric construction of non-activated C-SCF_(3) stereocenter via copper-catalyzed hydroallylation of SCF_(3)-alkenes
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作者 Wei-Cheng Zhao Yan He +4 位作者 Chen-Hui Jiang Peng Liu Qian Gao Duo-Duo Hu Xi-Sheng Wang 《Chinese Chemical Letters》 2026年第2期424-429,共6页
Fluorinated motifs are prevalent in both pharmaceuticals and agrochemicals.The incorporation of fluorine-containing moieties to drug candidates has emerged as a potent strategy for lead optimization in pharmaceutical ... Fluorinated motifs are prevalent in both pharmaceuticals and agrochemicals.The incorporation of fluorine-containing moieties to drug candidates has emerged as a potent strategy for lead optimization in pharmaceutical research and development.While extensive research has been devoted to constructing molecules that incorporate a trifluoromethylthio(SCF_(3)−)group on a stereogenic carbon,the synthesis of trifluoromethylthiolated alkanes featuring a SCF_(3)-substituted stereogenic carbon at non-activated site remains understudied.Herein,we report a Cu-catalyzed regio-and enantioselective hydroallylation of 1-trifluoromethylthiolated alkenes.Important to the process is the regio-and enantioselective Cu-H insertion to SCF_(3)-substituted alkene to form chiralα-SCF_(3) alkyl copper intermediates,outcompeting unproductive insertion to the coupling partner,and eventually proceed to afford optically active homoallylic trifluoromethylthiolated products. 展开更多
关键词 Asymmetric construction Non-activated Hydroallylation Trifluoromethylthio group COPPER-CATALYZED
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The Construction of Ouyang Xiu's Posthumous Image in the Song Dynasty
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作者 Yang Xiangkui Wang Minhan 《Contemporary Social Sciences》 2026年第1期18-34,共17页
The historical image of Ouyang Xiu constructed during the Song Dynasty evolved from a multifaceted portrayal that balanced his political and literary achievements into a singular cultural symbol.In the Northern Song D... The historical image of Ouyang Xiu constructed during the Song Dynasty evolved from a multifaceted portrayal that balanced his political and literary achievements into a singular cultural symbol.In the Northern Song Dynasty,writings by Ouyang Xiu's family and epitaphs by his colleagues crafted a balanced narrative emphasizing both his official duties and literary merits,thus constructing a dual image of him as a principled remonstrator and a literary master.In the Southern Song Dynasty,official historiography gradually eroded his complex persona as a political reformer by selectively trimming political disputes and emphasizing his literary lineage,ultimately establishing him as a cultural exemplar beyond factional strife.Throughout this evolution of historical writing,Ouyang Xiu's sharpness as a remonstrator was gradually obscured in historical texts,while his image as a literary master,revered by all,became firmly established.The reshaping of Ouyang Xiu's image in historical writings across the Northern and Southern Song dynasties not only reflects the logic of selecting scholar-official role models under the influence of official ideology but also reveals the inherent pattern whereby individual distinctiveness fades into symbolic construction in historical writing. 展开更多
关键词 Ouyang Xiu image construction biographical writing canonization
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Exploration and Practical Research on the Construction Model of the Emergency Care System Based on the Concept of“Linkage”
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作者 Yan Li 《Journal of Clinical and Nursing Research》 2026年第1期138-144,共7页
Against the backdrop of continuous social development and growing public health demands,the efficiency and scientific nature of the emergency care system are of paramount importance.This paper focuses on researching t... Against the backdrop of continuous social development and growing public health demands,the efficiency and scientific nature of the emergency care system are of paramount importance.This paper focuses on researching the construction of an emergency care system based on the concept of“linkage”,delving into its theoretical foundations,exploring innovative construction models,and analyzing practical cases.The study indicates that an emergency care system under the“linkage”concept can effectively integrate resources and enhance efficiency,providing new insights for improving the construction of the emergency care system.It aims to promote the development of the emergency care system towards a more scientific,efficient,and collaborative direction. 展开更多
关键词 Linkage concept Emergency care system construction model Practical cases
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Assessing the feasibility and environmental benefits of electrifying construction machinery in Beijing,China
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作者 Huawei Yi Yangyang Cui +6 位作者 Han Li Guanghan Huang Kaiyun Liu Linzhen Qu Jing Yan Lei Nie Yifeng Xue 《Journal of Environmental Sciences》 2026年第1期374-382,共9页
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
关键词 construction machinery ELECTRIFICATION Data envelopment analysis Analytic hierarchy process Air pollution
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Application and Practice of RPA Technology in FinTech Field-University-enterprise Cooperation Course Construction for Software Engineering Characteristic Talents Cultivation
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作者 Yixian Liu Jun Guo +2 位作者 Hongjuan Liu Dongming Chen Zhiliang Zhu 《计算机教育》 2026年第3期109-118,共10页
In response to the Ministry of Education’s requirements for building distinctive model software schools,Software College of Northeastern University and Shenzhen Kingdom Technology Co.,Ltd.jointly developed the specia... In response to the Ministry of Education’s requirements for building distinctive model software schools,Software College of Northeastern University and Shenzhen Kingdom Technology Co.,Ltd.jointly developed the specialized course“Application and Practice of RPA Technology in FinTech”.Addressing pain points in financial digital transformation,the course integrates robotic process automation(RPA)principles,financial domain knowledge,and RPA platform practice into a“technology-scenario-capability”trinity teaching system.Through 64 credit hours of integrated theory and practice,it covers RPA fundamentals,financial applications,RPA operations(including core skills like Web/desktop automation),and AI integration,cultivating students’ability to design and implement automated financial workflows.It innovatively features a RPA simulation platform,30+financial case studies,and modular task resources,creating a“teacher-machine-student”interactive model.Practice demonstrates the course effectively enhances students’integration of technical application and business acumen,providing a scalable paradigm for cultivating interdisciplinary FinTech talent. 展开更多
关键词 RPA technology FinTech field Characteristic talents cultivation University-enterprise cooperation Course construction
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Effects of the Xu-Argument-Based Continuation on L2 Syntactic Complexity:The Case of Verb-Argument Constructions
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作者 Xiaopeng Zhang Jianhua Chen 《Chinese Journal of Applied Linguistics》 2026年第1期38-56,159,160,共21页
This study investigated the impact of the xu-argument-based continuation on Chinese high school students’English syntactic complexity captured using verb-argument constructions(VACs)over an 8-week period.Participants... This study investigated the impact of the xu-argument-based continuation on Chinese high school students’English syntactic complexity captured using verb-argument constructions(VACs)over an 8-week period.Participants were two comparable groups of students:one group worked with English input texts(i.e.,E-E),while the other worked with Chinese input texts with the same content(i.e.,C-E).The results showed that over time,the E-E group exhibited a greater tendency to use a wider range of VACs,such as caused-motion constructions,attributives,passives,and phrasal verbs.At the same time,they reduced their use of simpler VACs like intransitive-motion and simple transitive constructions,especially when compared to the C-E group.This pattern was also evident in the topic-based writing during the posttest.These findings strongly support the effectiveness of xu-argument-based continuation tasks in promoting the development of L2 VAC knowledge.They suggest that tasks combining language input with output can significantly enhance learners’ability to use more sophisticated VACs. 展开更多
关键词 the xu-argument-based continuation task syntactic complexity verb-argument constructions Chinese high-school students
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Geostress Evolution and Construction Parameter Optimization in Shale Gas Infill Well Development
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作者 Yongjun Xiao Yuduo Sun +5 位作者 Jian Zheng Xiaojin Zhou Wang Liu Cheng Shen Qi Deng Hao Zhao 《Energy Engineering》 2026年第3期152-168,共17页
The shale gas development in China faces challenges such as complex reservoir conditions and high development costs.Based on the pore pressure and geostress coupling theory,this paper studies the geostress evolution l... The shale gas development in China faces challenges such as complex reservoir conditions and high development costs.Based on the pore pressure and geostress coupling theory,this paper studies the geostress evolution laws and fracture network characteristics of shale gas infill wells.A mechanism model of CN platform logging data and geomechanical parameters is established to simulate the influence of parent well’s production on the geostress in the infill well area.It is suggested that with the increase of production time,normal fault stress state and horizontal stress deflection will occur.The smaller the parent well spacing and the longer the production time,the earlier the normal fault stress state appears and the larger the range.Based on the model,the fracture network morphology and construction parameters of infill wells are optimized.parentparentparentparent The results indicate that:1:A well spacing of 500 m achieves a Pareto optimum between“full reserve coverage”and“stress barrier”;2:A parent well recovery degree of 30%corresponds to the critical point of stress reversal,where the lateral deflection rate of the infill fracture is less than 8%and the SRV loss is minimized;3:6-cluster intensive completion with twice the liquid intensity increases the fracture complexity index by 1.7 times,enhances well group EUR by 15.4%,and reduces single-well cost by 22%.This research fills the theoretical gap in the collaborative optimization of“multi-parameter,multi-objective and multi-constraint”and provide parameter optimization basis for shale gas infill well development in China and help to improve the development efficiency and economic benefits. 展开更多
关键词 Shale gas horizontal well geostress evolution infill well development numerical simulation construction parameter optimization
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Training Program Reform and Curriculum Construction of Characteristic Software Innovation Talents Based on the Integration of Industry and Education
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作者 Yixian Liu Jun Guo +2 位作者 Bin Zhang Dongming Chen Zhiliang Zhu 《计算机教育》 2026年第3期190-198,共9页
Aiming at the problem of innovative talent training in the industry field in characteristic software colleges,combined with the actual situation of Software College of Northeastern University,this paper analyzes the c... Aiming at the problem of innovative talent training in the industry field in characteristic software colleges,combined with the actual situation of Software College of Northeastern University,this paper analyzes the construction requirements of characteristic talent training mode and training scheme,puts forward the reform of characteristic software innovative talent training scheme integrating production and education,and takes the characteristic direction of financial technology as an example to introduce the curriculum construction based on industry-education integration and school-enterprise cooperation. 展开更多
关键词 Integration of industry and education Characteristic talents cultivation Program reform Curriculum construction
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Identification of Key Parameters for Temporary Guy Ropes in Sloping Central Tower Column and Brace Construction
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作者 Renfei Chang Liqiang Jin +2 位作者 Haihui Xie Kai Zhang Musheng Ye 《Structural Durability & Health Monitoring》 2026年第1期161-177,共17页
To investigate the impact of temporary structures on the mechanical behavior of shaped bridge towers during the construction process,the Dianbu River Special Bridge was selected as the engineering background.A finite ... To investigate the impact of temporary structures on the mechanical behavior of shaped bridge towers during the construction process,the Dianbu River Special Bridge was selected as the engineering background.A finite element model of the middle tower column during the construction stage was established using ABAQUS to analyze the effects of key parameters,including the angle and pretension of temporary cables,as well as the wall thickness and diameter of temporary diagonal braces.The study examines how these parameters influence the stresses at the towergirder consolidation.The results indicate that the angle of temporary cables significantly affects the tensile stresses at the tower-girder consolidation,while its impact on compressive stresses is minimal.Among all parameters,the pretension of temporary cables has the most pronounced effect on the stresses at the tower-girder consolidation.In contrast,the wall thickness of temporary diagonal braces has only a minor influence,whereas the diameter of temporary diagonal braces has an almost negligible impact.These findings provide valuable insights for optimizing the design and arrangement of temporary support structures in similar bridge construction projects. 展开更多
关键词 Anisotropic single tower cable-stayed bridge influence degree identification temporary cables temporary diagonal braces construction control
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Standards lead the high-quality development of intelligent construction in China
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作者 Cheng Zhijun 《China Standardization》 2026年第1期49-49,共1页
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
关键词 STANDARDS technical guidelines high quality development Ministry Housing Urban Rural Development intelligent constructionstandards replicable experience intelligent construction
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In vitro reconstruction and characterization of tissue-engineered human corneal epithelium with seeder cells from an untransfected human corneal epithelial cell line 被引量:3
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作者 Bin Xu, Xiu-Zhong Hu 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2012年第3期281-285,共5页
AIM: To demonstrate the morphology and structure of in vitro reconstructed tissue-engineered human corneal epithelium (TE-HCEP) with seeder cells from an untransfected HCEP cell line. METHODS: The TE-HCEPs were recons... AIM: To demonstrate the morphology and structure of in vitro reconstructed tissue-engineered human corneal epithelium (TE-HCEP) with seeder cells from an untransfected HCEP cell line. METHODS: The TE-HCEPs were reconstructed in vitro with seeder cells from an untransfected HCEP cell line, and scaffold carriers of denuded amniotic membrane (dAM) in air-liquid interface culture for 3, 5, 7 and 9 days, respectively. The specimens were examined with hematoxylin-eosin (HE) staining of paraffin-section, immunocytochemical staining, scanning and transmission electron microscopy. RESULTS: During in vitro reconstruction of TE-HCEP, HCEP cells formed a 3-4, 6-7 and 8-10 layers of an HCEP-like structure on dAMs in air-liquid interface culture for 3, 5 and 7 days, respectively. But the cells deceased to 5-6 layers and the structure of straified epithelium became loose at day 9. And the cells maintained positive expression of marker proteins (keratin 3 and keratin 12), cell-junction proteins (zonula occludens-1, E-cadherin, connexin 43 and integrin beta 1) and membrane transport protein of Na+-K+ ATPase. The HCEP cells in TE-HCEP were rich in microvilli on apical surface and established numerous cell-cell and cell-dAM junctions at day 5. CONCLUSION: The morphology and structure of the reconstructed TE-HCEP were similar to those of HCEP in vivo. The HCEP cells in the reconstructed TE-HCEP maintained the properties of HCEP cells, including abilities of forming intercellular and cell-extracellular matrix junctions and abilities of performing membrane transportation. The untransfected HCEP cells and dAMs could promisingly be used in reconstruction HCEP equivalent for clinical corneal epithelium transplantation. 展开更多
关键词 tissue-engineered human corneal epithelium in vitro reconstruction untransfected human corneal epithelial cell denuded amniotic membrane
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Open TBM Tunnel Intelligent Construction Technology 被引量:2
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作者 LIU Yongsheng CHEN Qiao +4 位作者 ZHANG Hepei LI Shu′ao LIN Chungang YIN Long LI Mengyu 《隧道建设(中英文)》 北大核心 2025年第4期816-833,I0025-I0042,共36页
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
关键词 TUNNEL open TBM intelligent construction deep learning machine vision
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A review of intelligent technologies for underground construction and infrastructure maintenance 被引量:2
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作者 Weiqiang Xie Wenzhao Meng Wei Wu 《Intelligent Geoengineering》 2025年第1期22-34,共13页
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
关键词 Underground construction Infrastructure maintenance In-situ testing Intelligent monitoring Geophysical investigation
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Progress in the construction strategy of noble metal active sites for zeolite-based PNA and VOCs catalysts 被引量:1
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作者 Yuan Yao Haodan Cheng +5 位作者 Guocai Zhong Xiaolong Tang Honghong Yi Shunzheng Zhao Fengyu Gao Qingjun Yu 《Green Energy & Environment》 2025年第4期709-732,共24页
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
关键词 Noble metal Zeolites constructing strategy PNA VOCS
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Smart Techniques Promoting Sustainability in Construction Engineering and Management 被引量:2
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作者 Song-Shun Lin Shui-Long Shen +1 位作者 Annan Zhou Xiang-Sheng Chen 《Engineering》 2025年第2期262-282,共21页
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
关键词 construction engineering and management Multi-criteria decision-making techniques Intelligent techniques Digital transformation SUSTAINABILITY
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FURobot:A software control platform for construction robots for large-scale construction
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作者 LU Ming Philip F.YUAN 《土木与环境工程学报(中英文)》 北大核心 2025年第5期1-11,共11页
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
关键词 construction robots CUSTOMIZATION construction ROBOTICS KINEMATICS SOFTWARE
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Smoke and NO_(x)emission characteristics of in-use construction machinery base on substantial field measurement:A case study in Beijing,China 被引量:1
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作者 Huawei Yi Yangyang Cui +7 位作者 Lijun Zhu Yan Shen Han Li Guanghan Huang Linzhen Qu Dongdong Guo Lei Nie Yifeng Xue 《Journal of Environmental Sciences》 2025年第3期386-393,共8页
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
关键词 Fuel-oil construction machinery SMOKE NO_(x) Emission level Regulatory suggestion
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Bridging sciatic nerve gap using tissue-engineered nerves constructed with neural tissue-committed stem cells derived from bone marrow 被引量:1
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作者 Zhiying Zhang Congli Ren Chuansen Zhang Fang Liu Liang Li 《Neural Regeneration Research》 SCIE CAS CSCD 2009年第5期344-349,共6页
BACKGROUND: Schwann cells are the most commonly used cells for tissue-engineered nerves. However, autologous Schwann cells are of limited use in a clinical context, and allogeneic Schwann cells induce immunological r... BACKGROUND: Schwann cells are the most commonly used cells for tissue-engineered nerves. However, autologous Schwann cells are of limited use in a clinical context, and allogeneic Schwann cells induce immunological rejections. Cells that do not induce immunological rejections and that are relatively easy to acquire are urgently needed for transplantation. OBJECTIVE: To bridge sciatic nerve defects using tissue engineered nerves constructed with neural tissue-committed stem cells (NTCSCs) derived from bone marrow; to observe morphology and function of rat nerves following bridging; to determine the effect of autologous nerve transplantation, which serves as the gold standard for evaluating efficacy of tissue-engineered nerves. DESIGN, TIME AND SETTING: This randomized, controlled, animal experiment was performed in the Anatomical Laboratory and Biomedical Institute of the Second Military Medical University of Chinese PLA between September 2004 and April 2006. MATERIALS: Five Sprague Dawley rats, aged 1 month and weighing 100-150 g, were used for cell culture. Sixty Sprague Dawley rats aged 3 months and weighing 220-250 g, were used to establish neurological defect models. Nestin, neuron-specific enolase (NSE), glial fibrillary acidic protein (GFAP), and S-100 antibodies were provided by Santa Cruz Biotechnology, Inc., USA. Acellular nerve grafts were derived from dogs. METHODS: All rats, each with 1-cm gap created in the right sciatic nerve, were randomly assigned to three groups. Each group comprised 20 rats. Autograft nerve transplantation group: the severed 1-cm length nerve segment was reverted, but with the two ends exchanged; the proximal segment was sutured to the distal sciatic nerve stump and the distal segment to the proximal stump. Blank nerve scaffold transplantation group: a 1-cm length acellular nerve graft was used to bridge the sciatic nerve gap. NTCSC engineered nerve transplantation group: a 1-cm length acellular nerve graft, in which NTCSCs were inoculated, was used to bridge the sciatic nerve gap. MAIN OUTCOME MEASURES: Following surgery, sciatic nerve functional index and electrophysiology functions were evaluated for nerve conduction function, including conduction latency, conduction velocity, and action potential peak. Horseradish peroxidase (HRP, 20%) was injected into the gastrocnemius muscle to retrogradely label the 1-4 and L5 nerve ganglions, as well as neurons in the anterior horn of the spinal cord, in the three groups. Positive expression of nestin, NSE, GFAP, and S-100 were determined using an immunofluorescence double-labeling method. RESULTS: NTCSCs differentiated into neuronal-like cells and glial-like cells within 12 weeks after NTCSC engineered nerve transplantation. HRP retrograde tracing displayed a large amount of HRP-labeled neurons in I-45 nerve ganglions, as well as the anterior horn of the spinal cord, in both the autograft nerve transplantation and the NTCSC engineered nerve transplantation groups. However, few HRP-labeled neurons were detected in the blank nerve scaffold transplantation group. Nerve bridges in the autograft nerve transplantation and NTCSC engineered nerve transplantation groups exhibited similar morphology to normal nerves. Neither fractures or broken nerve bridges nor neuromas were found after bridging the sciatic nerve gap with NTCSCs-inoculated acellular nerve graft, indicating repair. Conduction latency, action potential, and conduction velocity in the NTCSC engineered nerve transplantation group were identical to the autograft nerve transplantation group (P 〉 0.05), but significantly different from the blank nerve scaffold transplantation group (P 〈 0.05). CONCLUSION" NTCSC tissue-engineered nerves were able to repair injured nerves and facilitated restoration of nerve conduction function, similar to autograft nerve transplantation. " 展开更多
关键词 tissue-engineered nerve nerve damage sciatic nerve neural tissue-committed stem cells d
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Construction of Ni_(2)P/CoP interface for highly efficient electrolysis of urea-assisted hydrogen production at industrial current densities 被引量:1
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作者 Borong Lu Chunmei Lv +3 位作者 Ying Xie Kai Zhu Ke Ye Xiaojin Li 《Chinese Journal of Catalysis》 2025年第2期163-175,共13页
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
关键词 Interface chemical strategy Theoretical predictions Advanced interface construction Directed charge transfer Urea oxidation reaction
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Spatiotemporal Evolution of Construction Land and Its Driving Mechanism in the Yangtze River Delta Region:A Perspective of Diverse Development Orientation 被引量:1
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作者 CHENG Qianwen LI Manchun +2 位作者 LI Feixue LIN Yukun LI Weiyue 《Chinese Geographical Science》 2025年第2期343-357,I0004-I0011,共23页
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
关键词 construction land spatial pattern spatial heterogeneity driving factors XGBoost Yangtze River Delta(YRD) China
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