Climate models are essential for understanding past,present,and future changes in atmospheric circulation,with circulation modes providing key sources of seasonal predictability and prediction uncertainties for both g...Climate models are essential for understanding past,present,and future changes in atmospheric circulation,with circulation modes providing key sources of seasonal predictability and prediction uncertainties for both global and regional climates.This study assesses the performance of models participating in phase 6 of the Coupled Model Intercomparison Project in simulating interannual variability modes of Northern Hemisphere 500-hPa geopotential height during winter and summer,distinguishing predictable(potentially predictable on seasonal or longer timescales)and unpredictable(intraseasonal and essentially unpredictable at long range)components,using reanalysis data and a variance decomposition method.Although most models effectively capture unpredictable modes in reanalysis,their ability to reproduce dominant predictable modes-specifically the Pacific-North American pattern,Arctic Oscillation,and Western Pacific Oscillation in winter,and the East Atlantic and North Atlantic Oscillations in summer-varies notably.An optimal ensemble is identified to distinguish(a)predictable-external modes,dominated by external forcing,and(b)predictable-internal modes,associated with slow internal variability,during the historical period(1950-2014)and the SSP5-8.5 scenario(2036-2100).Under increased radiative forcing,the leading winter/summer predictable-external mode exhibits a more uniform spatial distribution,remarkably larger trend and annual variance,and enhanced height-sea surface temperature(SST)covariance under SSP5-8.5 compared to historical conditions.The dominant winter/summer predictable-internal modes also exhibit increased variance and height-SST covariance under SSP5-8.5,along with localized changes in spatial configuration.Minimal changes are observed in spatial distribution or variance for dominant winter/summer unpredictable modes under SSP5-8.5.This study,from a predictive perspective,deepens our understanding of model uncertainties and projected changes in circulations.展开更多
Objective expertise evaluation of individuals,as a prerequisite stage for team formation,has been a long-term desideratum in large software development companies.With the rapid advancements in machine learning methods...Objective expertise evaluation of individuals,as a prerequisite stage for team formation,has been a long-term desideratum in large software development companies.With the rapid advancements in machine learning methods,based on reliable existing data stored in project management tools’datasets,automating this evaluation process becomes a natural step forward.In this context,our approach focuses on quantifying software developer expertise by using metadata from the task-tracking systems.For this,we mathematically formalize two categories of expertise:technology-specific expertise,which denotes the skills required for a particular technology,and general expertise,which encapsulates overall knowledge in the software industry.Afterward,we automatically classify the zones of expertise associated with each task a developer has worked on using Bidirectional Encoder Representations from Transformers(BERT)-like transformers to handle the unique characteristics of project tool datasets effectively.Finally,our method evaluates the proficiency of each software specialist across already completed projects from both technology-specific and general perspectives.The method was experimentally validated,yielding promising results.展开更多
The global monsoon system,encompassing the Asian-Australian,African,and American monsoons,sustains two-thirds of the world’s population by regulating water resources and agriculture.Monsoon anomalies pose severe risk...The global monsoon system,encompassing the Asian-Australian,African,and American monsoons,sustains two-thirds of the world’s population by regulating water resources and agriculture.Monsoon anomalies pose severe risks,including floods and droughts.Recent research associated with the implementation of the Global Monsoons Model Intercomparison Project under the umbrella of CMIP6 has advanced our understanding of its historical variability and driving mechanisms.Observational data reveal a 20th-century shift:increased rainfall pre-1950s,followed by aridification and partial recovery post-1980s,driven by both internal variability(e.g.,Atlantic Multidecadal Oscillation)and external forcings(greenhouse gases,aerosols),while ENSO drives interannual variability through ocean-atmosphere interactions.Future projections under greenhouse forcing suggest long-term monsoon intensification,though regional disparities and model uncertainties persist.Models indicate robust trends but struggle to quantify extremes,where thermodynamic effects(warming-induced moisture rise)uniformly boost heavy rainfall,while dynamical shifts(circulation changes)create spatial heterogeneity.Volcanic eruptions and proposed solar radiation modification(SRM)further complicate predictions:tropical eruptions suppress monsoons,whereas high-latitude events alter cross-equatorial flows,highlighting unresolved feedbacks.The emergent constraint approach is booming in terms of correcting future projections and reducing uncertainty with respect to the global monsoons.Critical challenges remain.Model biases and sparse 20th-century observational data hinder accurate attribution.The interplay between natural variability and anthropogenic forcings,along with nonlinear extreme precipitation risks under warming,demands deeper mechanistic insights.Additionally,SRM’s regional impacts and hemispheric monsoon interactions require systematic evaluation.Addressing these gaps necessitates enhanced observational networks,refined climate models,and interdisciplinary efforts to disentangle multiscale drivers,ultimately improving resilience strategies for monsoon-dependent regions.展开更多
Investigating the ecological impact of land use change in the context of the construction of national water network project is crucial,as it is imperative for achieving the sustainable development goals of the nationa...Investigating the ecological impact of land use change in the context of the construction of national water network project is crucial,as it is imperative for achieving the sustainable development goals of the national water network and guaranteeing regional ecological stability.Using the Danjiangkou Reservoir Area(DRA),China as the study area,this paper first examined the spatiotemporal dynamics of natural landscape patterns and ecosystem service values(ESV)in the DRA from 2000 to 2018 and then investigated the spatial clustering characteristics of the ESV using spatial statistical analysis tools.Finally,the patch-generating land use simulation(PLUS)model was used to simulate the natural landscape and future changes in the ESV of the DRA from 2018 to 2028 under four different development scenarios:business as usual(BAU),economic development(ED),ecological protection(EP),and shoreline protection(SP).The results show that:during 2000-2018,the construction of water facilities had a significant impact on regional land use/land cover(LULC)change,with a 24830 ha increase in watershed area.ESV exhibited an increasing trend,with a significant and growing spatial clustering effect.The transformation of farmland to water bodies led to accelerated ESV growth,while the transformation of forest land to farmland led to a decrease in the ESV.Normalized difference vegetation index(NDVI)had the strongest effect on the ESV.ESV exhibited a continuous increase from 2018 to 2028 under all the simulation scenarios.The EP scenario had the greatest increase in ESV,while the ED scenario had the smallest increase.The findings suggest that projected land use patterns under different scenarios have varied impacts on ecosystem services(ESs)and that the management and planning of the DRA should balance social,economic,ecological,and security benefits.nomic,ecological,and security benefits.展开更多
The construction projects’ dynamic and interconnected nature requires a comprehensive understanding of complexity during pre-construction. Traditional tools such as Gantt charts, CPM, and PERT often overlook uncertai...The construction projects’ dynamic and interconnected nature requires a comprehensive understanding of complexity during pre-construction. Traditional tools such as Gantt charts, CPM, and PERT often overlook uncertainties. This study identifies 20 complexity factors through expert interviews and literature, categorising them into six groups. The Analytical Hierarchy Process evaluated the significance of different factors, establishing their corresponding weights to enhance adaptive project scheduling. A system dynamics (SD) model is developed and tested to evaluate the dynamic behaviour of identified complexity factors. The model simulates the impact of complexity on total project duration (TPD), revealing significant deviations from initial deterministic estimates. Data collection and analysis for reliability tests, including normality and Cronbach alpha, to validate the model’s components and expert feedback. Sensitivity analysis confirmed a positive relationship between complexity and project duration, with higher complexity levels resulting in increased TPD. This relationship highlights the inadequacy of static planning approaches and underscores the importance of addressing complexity dynamically. The study provides a framework for enhancing planning systems through system dynamics and recommends expanding the model to ensure broader applicability in diverse construction projects.展开更多
Projective synchronization problems of a drive system and a particular response network were investigated,where the drive system is an arbitrary system with n+1 dimensions;it may be a linear or nonlinear system,and ev...Projective synchronization problems of a drive system and a particular response network were investigated,where the drive system is an arbitrary system with n+1 dimensions;it may be a linear or nonlinear system,and even a chaotic or hyperchaotic system,the response network is complex system coupled by N nodes,and every node is showed by the approximately linear part of the drive system.Only controlling any one node of the response network by designed controller can achieve the projective synchronization.Some numerical examples were employed to verify the effectiveness and correctness of the designed controller.展开更多
[Objective]The channel straightening project of the Pinglu Canal has fragmented the river course,compromising the integrity of original river course and causing ecosystem patchiness.Understanding the current status of...[Objective]The channel straightening project of the Pinglu Canal has fragmented the river course,compromising the integrity of original river course and causing ecosystem patchiness.Understanding the current status of fish resources and the characteristics of their diversity is crucial for the ecological management of the Pinglu Canal.[Methods]During the spring and autumn in 2021 and 2022,a survey of fish resources and species diversity in the Pinglu Canal was conducted using multi-mesh gill nets.A total of 125 fish species were collected,belonging to 10 orders,34 families,and 89 genera.[Results]The result showed that the Pinglu Canal contained three nationally protected Class II species,two endemic species of the Qinjiang River,three anadromous/migratory species,and eight invasive species,accounting for 2.4%,1.6%,2.4%,and 6.4%of the total species,respectively.The fish community primarily consisted of mid-and bottom-dwelling,adhesive-egg-laying,and omnivorous species.The Shannon-Wiener,Simpson,Margalef,and Pielou indices of the fish community in the Pinglu Canal ranged from 2.347 to 2.757,0.081 to 0.151,3.493 to 4.382,and 0.812 to 0.892,respectively.These indices showed relatively uniform distribution across different river reaches.[Conclusion]The result indicate that the fish community structure in the Pinglu Canal is relatively uniform.The reach from the Yujiang River to the Shaping River shows higher stability,while other river reaches experience moderate or severe disturbances.This study provides supplementary baseline data on the fish community structure in the Pinglu Canal and explores the potential impact of inter-basin connectivity on fish resources,aiming to provide a scientific basis for habitat restoration assessments after the channel straightening project.展开更多
This paper focuses on the procurement of construction projects in universities,conducting research on the influencing factors of procurement risks in such projects.By combining questionnaire surveys with expert interv...This paper focuses on the procurement of construction projects in universities,conducting research on the influencing factors of procurement risks in such projects.By combining questionnaire surveys with expert interviews,numerous factors affecting procurement are analyzed.Subsequently,these factors are refined and summarized to construct a procurement risk evaluation index system for construction projects,which includes three first-level indicators,such as process management risk and ethical/legal risk,and is further subdivided into 13 second-level indicators.展开更多
Benefit evaluation of debris flow prevention and control projects was one of the essential contents of debris flow prevention and mitigation work.In order to scientifically and quantitatively evaluate the comprehensiv...Benefit evaluation of debris flow prevention and control projects was one of the essential contents of debris flow prevention and mitigation work.In order to scientifically and quantitatively evaluate the comprehensive benefit of debris flow prevention and control projects,this study identified nine factors as evaluation indicators from economic,social,and ecological aspects.The projection pursuit(PP) model based on the improved particle swarm optimization(IPSO) algorithm was used to construct a mathematical model to evaluate the benefit of debris flow prevention and control projects.The interpolation method was applied to divide the benefit grades.The debris flow prevention and control projects in Qipan,Taoguan,Chutou,Anjia,and Mozi gullies in Wenchuan County were chosen as typical cases for empirical analysis.The case study revealed that,among the criteria layer indicators,investment per unit of the protected area,investment per unit of the protected population,the amount of water and soil conservation,and reduction rate of accumulation fan had the most significant weights.The social and ecological benefits were found to be the more important in the target layer.The comprehensive benefit of Qipan,Taoguan,Chutou,Anjia,and Mozi gullies was found to be 4.44,4.83,1.95,3,and 2,respectively.The benefit ranking of the five gullies was consistent with their effectiveness in disaster prevention ranking in the flood season of 2019.Therefore,it could prove that the newly-built benefit evaluation model was practical and feasible,and the evaluation results of the sample could be reasonably interpreted,which verified the effectiveness of the methods.展开更多
Currently,the international economic situation is becoming increasingly complex,and there is significant downward pressure on the global economy.In recent years,China’s infrastructure sector has experienced rapid gro...Currently,the international economic situation is becoming increasingly complex,and there is significant downward pressure on the global economy.In recent years,China’s infrastructure sector has experienced rapid growth,with the structure of its power engineering business gradually shifting from traditional infrastructure construction to more diversified areas such as production and operation,as well as emergency repairs.As a result,the transformation of mechanized construction in power transmission and transformation projects has become increasingly urgent.This article proposes a post-evaluation model based on game theory to improve comprehensive weighting and fuzzy grey relational projection sorting,which can be used to evaluate the optimal mechanized construction scheme for power transmission and transformation projects.The model begins by considering the entire lifecycle of power transmission and transformation projects.It constructs a post-evaluation index system that covers the planning and design stage,on-site construction stage,operation and maintenance stage,and the decommissioning and disposal stage,with corresponding calculation methods for each index.The fuzzy grey correlation projection sorting method is then employed to evaluate and rank the construction schemes.To validate the model’s effectiveness,a case study of a power transmission and transformation project in a specific region of China is used.The comprehensive benefits of three proposed mechanized construction schemes are evaluated and compared.According to the evaluation results,Scheme 1 is ranked the highest,with a membership degree of 0.870945,excelling in sustainability.These results suggest that the proposed model can effectively evaluate and make decisions regarding the optimal mechanized construction plan for power transmission and transformation projects.展开更多
Let X be a real uniformly convex and uniformly smooth Banach space and C a nonempty closed and convex subset of X.Let Π_(C):X→C denote the generalized metric projection operator introduced by Alber in[1].In this pap...Let X be a real uniformly convex and uniformly smooth Banach space and C a nonempty closed and convex subset of X.Let Π_(C):X→C denote the generalized metric projection operator introduced by Alber in[1].In this paper,we define the Gâteaux directional differentiability of Π_(C).We investigate some properties of the Gâteaux directional differentiability of Π_(C).In particular,if C is a closed ball,or a closed and convex cone(including proper closed subspaces),or a closed and convex cylinder,then,we give the exact representations of the directional derivatives of Π_(C).By comparing the results in[12]and this paper,we see the significant difference between the directional derivatives of the generalized metric projection operator Π_(C) and the Gâteaux directional derivatives of the standard metric projection operator PC.展开更多
We show that the volume of the projection bodyΠ(Z)of an n-dimensional zonotope Z with n+1 generators and of volume 1 is always exactly 2^(n).Moroever,we point out that an upper bound on the volume ofΠ(K)of a central...We show that the volume of the projection bodyΠ(Z)of an n-dimensional zonotope Z with n+1 generators and of volume 1 is always exactly 2^(n).Moroever,we point out that an upper bound on the volume ofΠ(K)of a centrally symmetric n-dimensional convex body of volume 1 is at least 2^(n)(9/8)^([n/3]).展开更多
This paper reviews the latest advancements in artificial intelligence-assisted R&D project initiation,aiming to provide intelligent solutions for R&D management.It thoroughly examines the value of artificial i...This paper reviews the latest advancements in artificial intelligence-assisted R&D project initiation,aiming to provide intelligent solutions for R&D management.It thoroughly examines the value of artificial intelligence technologies in four core areas:intelligent requirement analysis,technical feasibility assessment,market prospect forecasting,and automated risk identification.Furthermore,it proposes three forward-looking trends—enhanced intelligence,the establishment of industry standards,and deeper human-machine collaboration.These insights are expected to improve project approval success rates and shorten initiation timelines,driving a paradigm shift in R&D management from experience-based to data-driven decision-making.The review highlights how artificial intelligence,through machine learning,natural language processing,and data mining,effectively addresses chronic challenges in traditional initiation processes such as inefficiency,delayed decisions,and resource misallocation.It also identifies critical hurdles,including data quality,model interpretability,and organizational transformation,offering a vital reference framework for the future of intelligent R&D development.展开更多
The graduation project(thesis)in vocational undergraduate education aims to demonstrate students’comprehensive application of acquired knowledge and professional skills,with an emphasis on industry-oriented practical...The graduation project(thesis)in vocational undergraduate education aims to demonstrate students’comprehensive application of acquired knowledge and professional skills,with an emphasis on industry-oriented practical implementation.This paper first identifies key issues in vocational undergraduate graduation projects,then proposes solutions using the“Four Truths”principle adopted by electronic information majors at Xi’an Vocational University of Automobile.This approach requires students to solve real-world enterprise problems,deliver tangible outcomes,and gain practical competencies.Improvement measures include:optimizing topic selection to integrate theory with practice;enhancing school-enterprise collaboration to boost corporate involvement;implementing a“dualtutor”system with jointly built training bases;and refining evaluation mechanisms to increase student engagement.These strategies collectively elevate the quality of vocational undergraduate graduation projects.展开更多
This paper examines the challenges in the technical briefing process for construction projects,including a three-level system and issues related to formalization.An optimization approaches was introduced based on the ...This paper examines the challenges in the technical briefing process for construction projects,including a three-level system and issues related to formalization.An optimization approaches was introduced based on the PDCA cycle,alongside the application of BIM and AR technologies.The key preparatory measures were outlined in this study and the functions of the management system was mentioned.Through case comparisons,this paper demonstrated that these optimizations can significantly improve efficiency and quality,support the development of an evaluation system to verify results,and highlight the critical role of organizational support.展开更多
Construction project construction stage requires effective change visa management and dynamic cost control.This paper defines both,presents related theories,and details challenges in traditional methods.It then propos...Construction project construction stage requires effective change visa management and dynamic cost control.This paper defines both,presents related theories,and details challenges in traditional methods.It then proposes an integrated model with system architecture,functional modules,and practical strategies like BIM integrated workflows.A case study validates the effectiveness,and future research on AI enhanced change prediction and blockchain based audit trails is suggested.展开更多
This paper expounds the characteristics of BIM technology,including visualization,parameterization,and collaboration.It analyzes the quality control requirements of real estate projects and the problems of the traditi...This paper expounds the characteristics of BIM technology,including visualization,parameterization,and collaboration.It analyzes the quality control requirements of real estate projects and the problems of the traditional control system.It introduces the quality control strategies based on BIM,such as constructing the framework,combining with technologies to control deviations,etc.It also mentions the PDCA mechanism,application terminals,etc.,and points out the application obstacles and future development directions.展开更多
With the growth of the construction industry,risk management in construction projects has garnered significant attention from the academic community.Effective risk management during the decision-making stage can great...With the growth of the construction industry,risk management in construction projects has garnered significant attention from the academic community.Effective risk management during the decision-making stage can greatly enhance project management efficiency.This paper integrates the AHP-entropy value method and constructs a risk management model based on the DPSIR framework for construction projects.The model is applied to evaluate and analyze the risk level of the decision-making stage in a navigation and electricity hub project in Chongqing Municipality.The results demonstrate the scientific validity and effectiveness of the proposed model.展开更多
This paper explains the goal conflict between schedule and quality in construction projects,including how schedule compression can lead to quality risks,and how quality control may cause delays.It analyzes the interna...This paper explains the goal conflict between schedule and quality in construction projects,including how schedule compression can lead to quality risks,and how quality control may cause delays.It analyzes the internal logic of collaborative management and influencing factors such as construction plans.The paper also introduces collaborative management methods,such as establishing a responsibility traceability system based on Work Breakdown Structure(WBS),and emphasizes the role of intelligent construction technologies and their future development directions.展开更多
In the project procurement management process of telecommunication enterprises,due to the complexity of technology,the professional procurement project manager is responsible for the whole process of professional proc...In the project procurement management process of telecommunication enterprises,due to the complexity of technology,the professional procurement project manager is responsible for the whole process of professional procurement in a one-stop way.The integration of this management process superficially improves labor productivity,but in essence lacks effective checks and balances and supervision.In order to supervise the project procurement management process and ensure the legal compliance of procurement management,this paper studies the project procurement management process of telecommunication enterprises,proposes the optimization process of project procurement management in the segmentation of purchasing manager-business manager,and constructs a matrix project procurement management model,which will contribute to the overall improvement of the telecommunication enterprises’procurement performance.展开更多
基金supported by the National Natural Science Foundation of China(Grant Nos.U2342210 and 42275043)the National Institute of Natural Hazards,Ministry of Emergency Management of China(Grant Nos.J2223806,ZDJ2024-25 and ZDJ2025-34)。
文摘Climate models are essential for understanding past,present,and future changes in atmospheric circulation,with circulation modes providing key sources of seasonal predictability and prediction uncertainties for both global and regional climates.This study assesses the performance of models participating in phase 6 of the Coupled Model Intercomparison Project in simulating interannual variability modes of Northern Hemisphere 500-hPa geopotential height during winter and summer,distinguishing predictable(potentially predictable on seasonal or longer timescales)and unpredictable(intraseasonal and essentially unpredictable at long range)components,using reanalysis data and a variance decomposition method.Although most models effectively capture unpredictable modes in reanalysis,their ability to reproduce dominant predictable modes-specifically the Pacific-North American pattern,Arctic Oscillation,and Western Pacific Oscillation in winter,and the East Atlantic and North Atlantic Oscillations in summer-varies notably.An optimal ensemble is identified to distinguish(a)predictable-external modes,dominated by external forcing,and(b)predictable-internal modes,associated with slow internal variability,during the historical period(1950-2014)and the SSP5-8.5 scenario(2036-2100).Under increased radiative forcing,the leading winter/summer predictable-external mode exhibits a more uniform spatial distribution,remarkably larger trend and annual variance,and enhanced height-sea surface temperature(SST)covariance under SSP5-8.5 compared to historical conditions.The dominant winter/summer predictable-internal modes also exhibit increased variance and height-SST covariance under SSP5-8.5,along with localized changes in spatial configuration.Minimal changes are observed in spatial distribution or variance for dominant winter/summer unpredictable modes under SSP5-8.5.This study,from a predictive perspective,deepens our understanding of model uncertainties and projected changes in circulations.
基金supported by the project“Romanian Hub for Artificial Intelligence-HRIA”,Smart Growth,Digitization and Financial Instruments Program,2021–2027,MySMIS No.334906.
文摘Objective expertise evaluation of individuals,as a prerequisite stage for team formation,has been a long-term desideratum in large software development companies.With the rapid advancements in machine learning methods,based on reliable existing data stored in project management tools’datasets,automating this evaluation process becomes a natural step forward.In this context,our approach focuses on quantifying software developer expertise by using metadata from the task-tracking systems.For this,we mathematically formalize two categories of expertise:technology-specific expertise,which denotes the skills required for a particular technology,and general expertise,which encapsulates overall knowledge in the software industry.Afterward,we automatically classify the zones of expertise associated with each task a developer has worked on using Bidirectional Encoder Representations from Transformers(BERT)-like transformers to handle the unique characteristics of project tool datasets effectively.Finally,our method evaluates the proficiency of each software specialist across already completed projects from both technology-specific and general perspectives.The method was experimentally validated,yielding promising results.
基金supported by the National Key Research and Development Program of China(Grant No.2020YFA0608904)the International Partnership Program of the Chinese Academy of Sciences(Grant Nos.060GJHZ2023079GC and 134111KYSB20160031)+1 种基金supported by the Office of Science,U.S.Department of Energy(DOE)Biological and Environmental Research as part of the Regional and Global Model Analysis program area through the Water Cycle and Climate Extremes Modeling(WACCEM)scientific focus areaoperated for DOE by Battelle Memorial Institute under contract DE-AC05-76RL01830。
文摘The global monsoon system,encompassing the Asian-Australian,African,and American monsoons,sustains two-thirds of the world’s population by regulating water resources and agriculture.Monsoon anomalies pose severe risks,including floods and droughts.Recent research associated with the implementation of the Global Monsoons Model Intercomparison Project under the umbrella of CMIP6 has advanced our understanding of its historical variability and driving mechanisms.Observational data reveal a 20th-century shift:increased rainfall pre-1950s,followed by aridification and partial recovery post-1980s,driven by both internal variability(e.g.,Atlantic Multidecadal Oscillation)and external forcings(greenhouse gases,aerosols),while ENSO drives interannual variability through ocean-atmosphere interactions.Future projections under greenhouse forcing suggest long-term monsoon intensification,though regional disparities and model uncertainties persist.Models indicate robust trends but struggle to quantify extremes,where thermodynamic effects(warming-induced moisture rise)uniformly boost heavy rainfall,while dynamical shifts(circulation changes)create spatial heterogeneity.Volcanic eruptions and proposed solar radiation modification(SRM)further complicate predictions:tropical eruptions suppress monsoons,whereas high-latitude events alter cross-equatorial flows,highlighting unresolved feedbacks.The emergent constraint approach is booming in terms of correcting future projections and reducing uncertainty with respect to the global monsoons.Critical challenges remain.Model biases and sparse 20th-century observational data hinder accurate attribution.The interplay between natural variability and anthropogenic forcings,along with nonlinear extreme precipitation risks under warming,demands deeper mechanistic insights.Additionally,SRM’s regional impacts and hemispheric monsoon interactions require systematic evaluation.Addressing these gaps necessitates enhanced observational networks,refined climate models,and interdisciplinary efforts to disentangle multiscale drivers,ultimately improving resilience strategies for monsoon-dependent regions.
基金Under the auspices of National Natural Science Foundation of China(No.42371315,41901213)Natural Science Foundation of Hubei Province(No.2020CFB856)Project of Changjiang Survey,Planning,Design and Research Co.,Ltd(No.CX2022Z23)。
文摘Investigating the ecological impact of land use change in the context of the construction of national water network project is crucial,as it is imperative for achieving the sustainable development goals of the national water network and guaranteeing regional ecological stability.Using the Danjiangkou Reservoir Area(DRA),China as the study area,this paper first examined the spatiotemporal dynamics of natural landscape patterns and ecosystem service values(ESV)in the DRA from 2000 to 2018 and then investigated the spatial clustering characteristics of the ESV using spatial statistical analysis tools.Finally,the patch-generating land use simulation(PLUS)model was used to simulate the natural landscape and future changes in the ESV of the DRA from 2018 to 2028 under four different development scenarios:business as usual(BAU),economic development(ED),ecological protection(EP),and shoreline protection(SP).The results show that:during 2000-2018,the construction of water facilities had a significant impact on regional land use/land cover(LULC)change,with a 24830 ha increase in watershed area.ESV exhibited an increasing trend,with a significant and growing spatial clustering effect.The transformation of farmland to water bodies led to accelerated ESV growth,while the transformation of forest land to farmland led to a decrease in the ESV.Normalized difference vegetation index(NDVI)had the strongest effect on the ESV.ESV exhibited a continuous increase from 2018 to 2028 under all the simulation scenarios.The EP scenario had the greatest increase in ESV,while the ED scenario had the smallest increase.The findings suggest that projected land use patterns under different scenarios have varied impacts on ecosystem services(ESs)and that the management and planning of the DRA should balance social,economic,ecological,and security benefits.nomic,ecological,and security benefits.
文摘The construction projects’ dynamic and interconnected nature requires a comprehensive understanding of complexity during pre-construction. Traditional tools such as Gantt charts, CPM, and PERT often overlook uncertainties. This study identifies 20 complexity factors through expert interviews and literature, categorising them into six groups. The Analytical Hierarchy Process evaluated the significance of different factors, establishing their corresponding weights to enhance adaptive project scheduling. A system dynamics (SD) model is developed and tested to evaluate the dynamic behaviour of identified complexity factors. The model simulates the impact of complexity on total project duration (TPD), revealing significant deviations from initial deterministic estimates. Data collection and analysis for reliability tests, including normality and Cronbach alpha, to validate the model’s components and expert feedback. Sensitivity analysis confirmed a positive relationship between complexity and project duration, with higher complexity levels resulting in increased TPD. This relationship highlights the inadequacy of static planning approaches and underscores the importance of addressing complexity dynamically. The study provides a framework for enhancing planning systems through system dynamics and recommends expanding the model to ensure broader applicability in diverse construction projects.
基金Supported by the National Natural Science Foundation of China (11161027)。
文摘Projective synchronization problems of a drive system and a particular response network were investigated,where the drive system is an arbitrary system with n+1 dimensions;it may be a linear or nonlinear system,and even a chaotic or hyperchaotic system,the response network is complex system coupled by N nodes,and every node is showed by the approximately linear part of the drive system.Only controlling any one node of the response network by designed controller can achieve the projective synchronization.Some numerical examples were employed to verify the effectiveness and correctness of the designed controller.
文摘[Objective]The channel straightening project of the Pinglu Canal has fragmented the river course,compromising the integrity of original river course and causing ecosystem patchiness.Understanding the current status of fish resources and the characteristics of their diversity is crucial for the ecological management of the Pinglu Canal.[Methods]During the spring and autumn in 2021 and 2022,a survey of fish resources and species diversity in the Pinglu Canal was conducted using multi-mesh gill nets.A total of 125 fish species were collected,belonging to 10 orders,34 families,and 89 genera.[Results]The result showed that the Pinglu Canal contained three nationally protected Class II species,two endemic species of the Qinjiang River,three anadromous/migratory species,and eight invasive species,accounting for 2.4%,1.6%,2.4%,and 6.4%of the total species,respectively.The fish community primarily consisted of mid-and bottom-dwelling,adhesive-egg-laying,and omnivorous species.The Shannon-Wiener,Simpson,Margalef,and Pielou indices of the fish community in the Pinglu Canal ranged from 2.347 to 2.757,0.081 to 0.151,3.493 to 4.382,and 0.812 to 0.892,respectively.These indices showed relatively uniform distribution across different river reaches.[Conclusion]The result indicate that the fish community structure in the Pinglu Canal is relatively uniform.The reach from the Yujiang River to the Shaping River shows higher stability,while other river reaches experience moderate or severe disturbances.This study provides supplementary baseline data on the fish community structure in the Pinglu Canal and explores the potential impact of inter-basin connectivity on fish resources,aiming to provide a scientific basis for habitat restoration assessments after the channel straightening project.
文摘This paper focuses on the procurement of construction projects in universities,conducting research on the influencing factors of procurement risks in such projects.By combining questionnaire surveys with expert interviews,numerous factors affecting procurement are analyzed.Subsequently,these factors are refined and summarized to construct a procurement risk evaluation index system for construction projects,which includes three first-level indicators,such as process management risk and ethical/legal risk,and is further subdivided into 13 second-level indicators.
基金financially supported by the National Key Research and Development Program(No.2018YFC1505402)the National Natural Science Foundation of China(No.41871174)+1 种基金the Science and Technology Department of Sichuan Province(No.2020YFSY0013)the Fundamental Research Funds for the Central Universities Project(No.2682019CX19)。
文摘Benefit evaluation of debris flow prevention and control projects was one of the essential contents of debris flow prevention and mitigation work.In order to scientifically and quantitatively evaluate the comprehensive benefit of debris flow prevention and control projects,this study identified nine factors as evaluation indicators from economic,social,and ecological aspects.The projection pursuit(PP) model based on the improved particle swarm optimization(IPSO) algorithm was used to construct a mathematical model to evaluate the benefit of debris flow prevention and control projects.The interpolation method was applied to divide the benefit grades.The debris flow prevention and control projects in Qipan,Taoguan,Chutou,Anjia,and Mozi gullies in Wenchuan County were chosen as typical cases for empirical analysis.The case study revealed that,among the criteria layer indicators,investment per unit of the protected area,investment per unit of the protected population,the amount of water and soil conservation,and reduction rate of accumulation fan had the most significant weights.The social and ecological benefits were found to be the more important in the target layer.The comprehensive benefit of Qipan,Taoguan,Chutou,Anjia,and Mozi gullies was found to be 4.44,4.83,1.95,3,and 2,respectively.The benefit ranking of the five gullies was consistent with their effectiveness in disaster prevention ranking in the flood season of 2019.Therefore,it could prove that the newly-built benefit evaluation model was practical and feasible,and the evaluation results of the sample could be reasonably interpreted,which verified the effectiveness of the methods.
文摘Currently,the international economic situation is becoming increasingly complex,and there is significant downward pressure on the global economy.In recent years,China’s infrastructure sector has experienced rapid growth,with the structure of its power engineering business gradually shifting from traditional infrastructure construction to more diversified areas such as production and operation,as well as emergency repairs.As a result,the transformation of mechanized construction in power transmission and transformation projects has become increasingly urgent.This article proposes a post-evaluation model based on game theory to improve comprehensive weighting and fuzzy grey relational projection sorting,which can be used to evaluate the optimal mechanized construction scheme for power transmission and transformation projects.The model begins by considering the entire lifecycle of power transmission and transformation projects.It constructs a post-evaluation index system that covers the planning and design stage,on-site construction stage,operation and maintenance stage,and the decommissioning and disposal stage,with corresponding calculation methods for each index.The fuzzy grey correlation projection sorting method is then employed to evaluate and rank the construction schemes.To validate the model’s effectiveness,a case study of a power transmission and transformation project in a specific region of China is used.The comprehensive benefits of three proposed mechanized construction schemes are evaluated and compared.According to the evaluation results,Scheme 1 is ranked the highest,with a membership degree of 0.870945,excelling in sustainability.These results suggest that the proposed model can effectively evaluate and make decisions regarding the optimal mechanized construction plan for power transmission and transformation projects.
文摘Let X be a real uniformly convex and uniformly smooth Banach space and C a nonempty closed and convex subset of X.Let Π_(C):X→C denote the generalized metric projection operator introduced by Alber in[1].In this paper,we define the Gâteaux directional differentiability of Π_(C).We investigate some properties of the Gâteaux directional differentiability of Π_(C).In particular,if C is a closed ball,or a closed and convex cone(including proper closed subspaces),or a closed and convex cylinder,then,we give the exact representations of the directional derivatives of Π_(C).By comparing the results in[12]and this paper,we see the significant difference between the directional derivatives of the generalized metric projection operator Π_(C) and the Gâteaux directional derivatives of the standard metric projection operator PC.
文摘We show that the volume of the projection bodyΠ(Z)of an n-dimensional zonotope Z with n+1 generators and of volume 1 is always exactly 2^(n).Moroever,we point out that an upper bound on the volume ofΠ(K)of a centrally symmetric n-dimensional convex body of volume 1 is at least 2^(n)(9/8)^([n/3]).
文摘This paper reviews the latest advancements in artificial intelligence-assisted R&D project initiation,aiming to provide intelligent solutions for R&D management.It thoroughly examines the value of artificial intelligence technologies in four core areas:intelligent requirement analysis,technical feasibility assessment,market prospect forecasting,and automated risk identification.Furthermore,it proposes three forward-looking trends—enhanced intelligence,the establishment of industry standards,and deeper human-machine collaboration.These insights are expected to improve project approval success rates and shorten initiation timelines,driving a paradigm shift in R&D management from experience-based to data-driven decision-making.The review highlights how artificial intelligence,through machine learning,natural language processing,and data mining,effectively addresses chronic challenges in traditional initiation processes such as inefficiency,delayed decisions,and resource misallocation.It also identifies critical hurdles,including data quality,model interpretability,and organizational transformation,offering a vital reference framework for the future of intelligent R&D development.
基金2024 General Project of Shaanxi Province’s Education Science“14th Five-Year Plan”(SGH24Y3100)2025 Research Project on Vocational Education Teaching Reform of Shaanxi Vocational and Technical Education Association(2025SZX674)。
文摘The graduation project(thesis)in vocational undergraduate education aims to demonstrate students’comprehensive application of acquired knowledge and professional skills,with an emphasis on industry-oriented practical implementation.This paper first identifies key issues in vocational undergraduate graduation projects,then proposes solutions using the“Four Truths”principle adopted by electronic information majors at Xi’an Vocational University of Automobile.This approach requires students to solve real-world enterprise problems,deliver tangible outcomes,and gain practical competencies.Improvement measures include:optimizing topic selection to integrate theory with practice;enhancing school-enterprise collaboration to boost corporate involvement;implementing a“dualtutor”system with jointly built training bases;and refining evaluation mechanisms to increase student engagement.These strategies collectively elevate the quality of vocational undergraduate graduation projects.
文摘This paper examines the challenges in the technical briefing process for construction projects,including a three-level system and issues related to formalization.An optimization approaches was introduced based on the PDCA cycle,alongside the application of BIM and AR technologies.The key preparatory measures were outlined in this study and the functions of the management system was mentioned.Through case comparisons,this paper demonstrated that these optimizations can significantly improve efficiency and quality,support the development of an evaluation system to verify results,and highlight the critical role of organizational support.
文摘Construction project construction stage requires effective change visa management and dynamic cost control.This paper defines both,presents related theories,and details challenges in traditional methods.It then proposes an integrated model with system architecture,functional modules,and practical strategies like BIM integrated workflows.A case study validates the effectiveness,and future research on AI enhanced change prediction and blockchain based audit trails is suggested.
文摘This paper expounds the characteristics of BIM technology,including visualization,parameterization,and collaboration.It analyzes the quality control requirements of real estate projects and the problems of the traditional control system.It introduces the quality control strategies based on BIM,such as constructing the framework,combining with technologies to control deviations,etc.It also mentions the PDCA mechanism,application terminals,etc.,and points out the application obstacles and future development directions.
文摘With the growth of the construction industry,risk management in construction projects has garnered significant attention from the academic community.Effective risk management during the decision-making stage can greatly enhance project management efficiency.This paper integrates the AHP-entropy value method and constructs a risk management model based on the DPSIR framework for construction projects.The model is applied to evaluate and analyze the risk level of the decision-making stage in a navigation and electricity hub project in Chongqing Municipality.The results demonstrate the scientific validity and effectiveness of the proposed model.
文摘This paper explains the goal conflict between schedule and quality in construction projects,including how schedule compression can lead to quality risks,and how quality control may cause delays.It analyzes the internal logic of collaborative management and influencing factors such as construction plans.The paper also introduces collaborative management methods,such as establishing a responsibility traceability system based on Work Breakdown Structure(WBS),and emphasizes the role of intelligent construction technologies and their future development directions.
文摘In the project procurement management process of telecommunication enterprises,due to the complexity of technology,the professional procurement project manager is responsible for the whole process of professional procurement in a one-stop way.The integration of this management process superficially improves labor productivity,but in essence lacks effective checks and balances and supervision.In order to supervise the project procurement management process and ensure the legal compliance of procurement management,this paper studies the project procurement management process of telecommunication enterprises,proposes the optimization process of project procurement management in the segmentation of purchasing manager-business manager,and constructs a matrix project procurement management model,which will contribute to the overall improvement of the telecommunication enterprises’procurement performance.
