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Predictable and Unpredictable Modes of Northern Hemisphere Atmospheric Circulation in CMIP6:Evaluation and Projections
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作者 Kairan YING Dabang JIANG Linhao ZHONG 《Advances in Atmospheric Sciences》 2026年第1期135-156,共22页
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
关键词 interannual mode of atmospheric circulation CMIP6 predictable unpredictable EVALUATION projectION
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Individual Software Expertise Formalization and Assessment from Project Management Tool Databases
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作者 Traian-Radu Plosca Alexandru-Mihai Pescaru +1 位作者 Bianca-Valeria Rus Daniel-Ioan Curiac 《Computers, Materials & Continua》 2026年第1期389-411,共23页
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
关键词 Expertise formalization transformer-based models natural language processing augmented data project management tool skill classification
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The Observed and Projected Changes of Global Monsoons:Current Status and Future Perspectives
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作者 Tianjun ZHOU Xiaolong CHEN +11 位作者 Wenxia ZHANG Bo WU Ziming CHEN Jie JIANG Xin HUANG Shuai HU Meng ZUO Wenmin MAN Lixia ZHANG Zhun GUO Pengfei LIN Lu WANG 《Advances in Atmospheric Sciences》 2026年第1期30-58,共29页
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
关键词 global monsoons interannual variability decadal variability detection and attribution climate extreme events projection uncertainty
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A Nexus for East Africa--China-supported projects help East Africans to boost energy, water and food security
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作者 RICHARD WETAYA 《ChinAfrica》 2026年第1期44-45,共2页
Andrew Wangota,a 48-year-old Ugandan farmer,has been using agrivoltaics technology,a solar technology that uses agricultural land for both food production and solar power generation,on his farm in Bunashimolo Parish,B... Andrew Wangota,a 48-year-old Ugandan farmer,has been using agrivoltaics technology,a solar technology that uses agricultural land for both food production and solar power generation,on his farm in Bunashimolo Parish,Bukyiende Subcounty in Uganda where he has been cultivating plantain,coffee and Irish potatoes for the past 16 years. 展开更多
关键词 water security solar technology NEXUS irish potatoes East Africa energy security China supported projects agrivoltaics technologya
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Real-time computerized tomography(CT) test of failure process of jointed granite under unloading in three gorges project(TGP) 被引量:3
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作者 任建喜 《Journal of Coal Science & Engineering(China)》 2004年第2期11-14,共4页
This paper deals with the real-time computerized tomography(CT) test for moni- toring the complete damage failure process of a single-crack granite specimen that is subjected to the confining pressure unloading. For t... This paper deals with the real-time computerized tomography(CT) test for moni- toring the complete damage failure process of a single-crack granite specimen that is subjected to the confining pressure unloading. For this purpose, the State Key Laboratory of Frozen Soil of China has developed a special CT Triaxial Testing Equipment for Rocks and Soils that can give clear images of complete failure process of a rock specimen during removal of confining pressures, including various stages of development and penetration of cracks etc. The results have shown that it is easy for failure phenomenon to happen suddenly in the process of unloading condition of jointed rocks. 展开更多
关键词 jointed granite of tgp unloading confining pressure rock specimen
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Mechanisms of suspended sediment restoration and bed level compensation in downstream reaches of the Three Gorges Projects(TGP) 被引量:6
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作者 张为 杨云平 +5 位作者 张明进 李义天 朱玲玲 由星莹 王冬 徐俊锋 《Journal of Geographical Sciences》 SCIE CSCD 2017年第4期463-480,共18页
River basin reservoir construction affects water and sediment transport processes in downstream reaches. The downstream impact of the Three Gorges Projects (TGP) has started to become apparent: (1) reduction in f... River basin reservoir construction affects water and sediment transport processes in downstream reaches. The downstream impact of the Three Gorges Projects (TGP) has started to become apparent: (1) reduction in flood duration and discharge, and significant reduction in sediment load. Although there was some restoration in downstream sediment load, the total amount did not exceed the pre-impoundment annual average; (2) in 2003-2014 the d 〉 0.125 mm (coarse sand) load was restored to some degree, and to a maximum at Jianli Station, which was mainly at the pre-impoundment average. After restoration, erosion and deposition characteristics of the sediment was identical to that before impoundment. The degree of restoration during 2008-2014 was less than during 2003-2007; (3) after TGP im- poundment, there was some restoration in d 〈 0.125 mm (fine sand) sediment load, however, it was {ower than the pre-impoundment average; (4) due to riverbed compensation, the d 〉 0.125 mm sediment load recovered to a certain degree after impoundment, however, the total did not exceed 4400x104 t/y. This was mainly limited by flood duration and the average flow rate, and was less affected by upstream main stream, tributaries, or lakes. Restoration of d 〈 0.125 mm suspended sediment was largely controlled by upstream main stream, tributaries, and lakes, as well as by riverbed compensation. Due to bed armoring, riverbed fine suspended sediment compensation capability was weakened; (5) during 2003-2007 and 2008-2014, Yichang to Zhicheng and upper Jingjiang experienced coarse and fine erosion,lower Jingjiang experienced coarse deposition and fine erosion, Hankou to Datong had coarse deposition and fine erosion, and Chenglingji and Hankou was characterized by coarse deposition and fine sand erosion in 2003-2007, and coarse and fine erosion in 2008-2014. This difference was controlled by flood duration and number at Luoshan Station. 展开更多
关键词 sediment restoration riverbed compensation tgp middle and lower reaches of the Yangtze River
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从《Project 2025》看特朗普第二任期遏制“一带一路”倡议动向
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作者 毛新雅 《海外投资与出口信贷》 2025年第3期13-15,共3页
《Project 2025》由美国保守派公共政策智库传统基金会(Heritage Foundation)编写,着重为应对美国最深层次的挑战提出政策建议。《Project 2025》对中国“一带一路”倡议持竞争和对抗态度,其提出采取强化美国在拉美地区影响力、继续实... 《Project 2025》由美国保守派公共政策智库传统基金会(Heritage Foundation)编写,着重为应对美国最深层次的挑战提出政策建议。《Project 2025》对中国“一带一路”倡议持竞争和对抗态度,其提出采取强化美国在拉美地区影响力、继续实施“印太战略”、变革能源产业政策和针对性恢复国际发展援助等方式,遏制中国“一带一路”倡议,可能对特朗普第二任期相关政策产生影响。 展开更多
关键词 中美关系 “一带一路” 传统基金会 project 2025》
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“任务支持型”与“基于任务型”语言教学在PEP小学英语教材Project板块中的应用
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作者 周瓦 《英语学习(中英文)》 2025年第9期33-41,共9页
人教版小学《英语》(PEP)(2024年版)教材新增的Project板块为任务型语言教学实践提供了新的载体。然而,目前部分教师在授课时习惯将该板块的内容拆分融入单元其他板块,或简单沿用教材既定的“语言准备—任务实践—分享”三步骤,缺乏对... 人教版小学《英语》(PEP)(2024年版)教材新增的Project板块为任务型语言教学实践提供了新的载体。然而,目前部分教师在授课时习惯将该板块的内容拆分融入单元其他板块,或简单沿用教材既定的“语言准备—任务实践—分享”三步骤,缺乏对其内涵的深度挖掘与创新设计。本研究深入探讨教材Project板块的任务要素、类型特征及其教学理念,尝试在教学中应用“任务支持型”和“基于任务型”两种语言教学模式,探索任务设计的多元化与差异化路径,旨在提升小学低年级学生的综合语言应用能力,也为适合高年级学生的项目化教学深入实施提供新思路。 展开更多
关键词 PEP小学英语教材 project板块 “任务支持型”语言教学 教学设计创新
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Developing Projects with Low-code Combined with ChatGPT
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作者 Wei Xiong Bing Li +1 位作者 Zhao Wu Bo Hang 《计算机教育》 2023年第12期204-213,共10页
This paper aims to explore a simpler and more user-friendly way of generating software based on model-driven development.Previous studies have attempted to generate code from domain models,hoping to reduce coding time... This paper aims to explore a simpler and more user-friendly way of generating software based on model-driven development.Previous studies have attempted to generate code from domain models,hoping to reduce coding time by increasing modeling time.However,as code tools become more advanced,it is challenging to improve efficiency because models are abstract while implementations are concrete.This paper proposes a novel approach that integrates ChatGPT as a plug-in into the whole R&D process and combines it with our code generation tool to enhance R&D efficiency.We have developed some demos to demonstrate the effectiveness of our approach.According to our evaluation,our approach can save more than 90%of the work in implementing the code generation tool,leaving only about 10%of the work for code review,code improvement,and unit testing. 展开更多
关键词 ChatgpT Low-code Code generation Software engineering project development
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Global burden of cervical cancer:current estimates,temporal trend and future projections based on the GLOBOCAN 2022 被引量:4
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作者 Jie Wu Qianyun Jin +10 位作者 Yunmeng Zhang Yuting Ji Jingjing Li Xiaomin Liu Hongyuan Duan Zhuowei Feng Ya Liu Yacong Zhang Zhangyan Lyu Lei Yang Yubei Huang 《Journal of the National Cancer Center》 2025年第3期322-329,共8页
Background Cervical cancer is the only cancer that can be eliminated worldwide.Tracking the latest burden of cervical cancer is critical toward the targets set by World Health Organization(WHO)to eliminate cervical ca... Background Cervical cancer is the only cancer that can be eliminated worldwide.Tracking the latest burden of cervical cancer is critical toward the targets set by World Health Organization(WHO)to eliminate cervical cancer as a major public health problem.Methods All data were extracted from the Global Cancer Observatory(GLOBOCAN)2022.Age-standardized incidence rate(ASIR)and mortality rates(ASMR)of cervical cancer were compared and linked to Human Development Index(HDI)between populations.The estimated annual percentage changes(EAPCs)were used to characterize the temporal trend in ASIR/ASMR,and demographic estimates were projected up to 2050.Results Globally,an estimated 662,044 cases(ASIR:14.12/100,000)and 348,709 deaths(ASMR:7.08/100,000)from cervical cancer occurred in 2022,corresponding to the fourth cause of cancer morbidity and mortality in women worldwide.Specifically,42%of cases and 39%of deaths occurred in China(23%and 16%)and India(19%and 23%).Both ASIR and ASMR of cervical cancer decreased with HDI,and similar decreasing links were observed for both early-onset(0–39 years)and late-onset(≥40 years)cervical cancer.Both ASIR and ASMR of overall cervical cancer showed decreasing trends during 2003–2012(EAPC:0.04%and-1.03%);however,upward trends were observed for early-onset cervical cancer(EAPC:1.16%and 0.57%).If national rates in 2022 remain stable,the estimated cases and deaths from cervical cancer are projected to increase by 56.8%and 80.7%up to 2050.Moreover,the projected increase of early-onset cervical cancer is mainly observed in transitioning countries,while decreased burden is expected in transitioned countries.Conclusions Cervical cancer remains a common cause of cancer death in many countries,especially in transitioning countries.Unless scaling-up preventive interventions,human papillomavirus(HPV)vaccination and cervical cancer screening,as well as systematic cooperation within government,civil societies,and private enterprises,the global burden of cervical cancer would be expected to increase in the future. 展开更多
关键词 Cervical cancer INCIDENCE MORTALITY Temporal trend Future projection
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Decision-making & Practice on the Three Gorges Project(TGP)
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作者 Lu Youmei (China Three Gorges Project Development Corporation, Yichang, Hubei 443002) 《工程科学(英文版)》 2003年第1期1-7,79,共8页
China Yangtze TGP is a particularly giant hydro development project in the world, with an enormous scale and complex technology. Seventy years project planning, verification and decision making and ten years const... China Yangtze TGP is a particularly giant hydro development project in the world, with an enormous scale and complex technology. Seventy years project planning, verification and decision making and ten years construction work demonstrate that not only great progress has been made within the projects implementation stage, but most of the conclusions from the verifications and decisions are correct as well. Some problems like sedimentation, environment and resettlement are still waiting to be proven in the actual operation of the project. This paper provides a brief introduction to the decision making and practice on TGP. 展开更多
关键词 YANGTZE River THREE Gorges project DECISION making PRACTICE
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Macro-decision-making on Phase I Construction of the Three Gorges Project (TGP)
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作者 Peng Qiyou (China Yangtze TGP Development Corporation, Yichang, Hubei\ 443002) 《工程科学(英文版)》 2003年第1期94-99,共6页
In this paper,the dominance of the national enterprise and current situation of project management are analyzed on the basis of sum of Phase Ⅰ Construction management of the Three Gorges Project.From the start point ... In this paper,the dominance of the national enterprise and current situation of project management are analyzed on the basis of sum of Phase Ⅰ Construction management of the Three Gorges Project.From the start point of idea modification and inner reformation of enterprise,some of concrete suggestions enhancing the project management, are offered in the paper. 展开更多
关键词 Phase CONSTRUCTION project management MACROSCOPIC decison\|making
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From Pilot to Planet: Scaling United Nations’ Blockchain Projects for a Sustainable Future 被引量:1
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作者 Roberta Pisani 《Chinese Business Review》 2025年第3期87-98,共12页
Within the framework of the 2030 Agenda and to achieve the Sustainable Development Goals(SDGs),science,technology and innovation play an even more central role.Building on this foundation,the primary objective of this... Within the framework of the 2030 Agenda and to achieve the Sustainable Development Goals(SDGs),science,technology and innovation play an even more central role.Building on this foundation,the primary objective of this paper is to explore the potential applications of blockchain in supporting the achievement of these sustainability goals.Starting from a review of the relevant literature on this topic,the main fields in which blockchain can contribute to sustainable development will be identified.The main blockchain applications will then be analyzed and categorized according to these SDGs.This research will then critically present the main blockchain-based projects that emerged in the first stage of the study and were implemented by the United Nations.The main objectives and benefits of each project will be analyzed.This is where the originality of this paper lies.To the best of the author’s knowledge,this is one of the first attempts to present a comprehensive overview of the United Nations’projects related to SDGs 1,2,5,7,9,13,and 16.This paper,which bridges the gap between innovation management and the sustainability field,will contribute to the increasingly current debate on sustainability issues and be beneficial to scholars,practitioners,and policymakers alike. 展开更多
关键词 blockchain SDGs SUSTAINABILITY sustainable development innovation management case studies blockchain-based projects
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以Project为成果导向进行单元整体教学--以新版PEP《英语》三年级上册Unit 3 Amazing animals为例 被引量:1
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作者 何玲丽 《教学月刊(小学版)(综合)》 2025年第1期46-49,共4页
新版PEP《英语》增设了Project板块,旨在引导学生通过同伴合作、作品制作、成果交流、活动评价等方式综合运用所学语言知识和技能完成学习任务,展现学习成果,从而培养学生的综合语言运用能力、开放性思维能力和创新意识。为了有效落实... 新版PEP《英语》增设了Project板块,旨在引导学生通过同伴合作、作品制作、成果交流、活动评价等方式综合运用所学语言知识和技能完成学习任务,展现学习成果,从而培养学生的综合语言运用能力、开放性思维能力和创新意识。为了有效落实教学目标,保证教学效果,教师可以Project为成果导向,在分析教材与学情的基础上制定单元教学目标,完成教学设计,实施教学过程,落实教学评价,初步培养学生的英语学科核心素养。 展开更多
关键词 成果导向 小学英语 新教材 project板块 单元整体
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Color projector light intensity adaptive high dynamic range 3D measurement method
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作者 HUANG Hao-zhen NIU Bin +2 位作者 CHENG Shen QU Xing-hua ZHANG Fu-min 《中国光学(中英文)》 北大核心 2025年第5期1219-1229,共11页
The Fringe Projection Profilometry(FPP)system with a single exposure time or a single projection intensity is limited by the dynamic range of the camera,which can lead to overexposure and underexposure of the image,re... The Fringe Projection Profilometry(FPP)system with a single exposure time or a single projection intensity is limited by the dynamic range of the camera,which can lead to overexposure and underexposure of the image,resulting in point cloud loss or reduced accuracy.To address this issue,unlike the pixel modulation method of projectors,we utilize the characteristics of color projectors where the intensity of the three-channel LED can be controlled independently.We propose a method for separating the projector's three-channel light intensity,combined with a color camera,to achieve single exposure and multi-intensity image acquisition.Further,the crosstalk coefficient is applied to predict the three-channel reflectance of the measured object.By integrating clustering and channel mapping,we establish a pixel-level mapping model between the projector's three-channel current and the camera's three-channel image intensity,which realizes the optimal projection current prediction and the high dynamic range(HDR)image acquisition.The proposed method allows for high-precision three-dimensional(3D)data acquisition of HDR scenes with a single exposure.The effectiveness of this method has been validated through experiments with standard planes and standard steps,showing a significant reduction in mean absolute error(44.6%)compared to existing singleexposure HDR methods.Additionally,the number of images required for acquisition is significantly reduced(by 70.8%)compared to multi-exposure fusion methods.This proposed method has great potential in various FPP-related fields. 展开更多
关键词 fringe projection profilometry crosstalk coefficient optimal projection currents high dynamic range
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Understanding Complexity at the Pre-Construction Stage of Project Planning for Construction Projects
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作者 Mehran Barani Shikhrobat Roger Flanagan Shabnam Kabiri 《American Journal of Operations Research》 2025年第1期1-27,共27页
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
关键词 project Planning project Complexity Measurement Uncertainty Management project Risk Management Strategic project Scheduling
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Projective synchronization control and simulation of drive system and response network
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作者 LI De-kui 《兰州大学学报(自然科学版)》 北大核心 2025年第2期208-214,共7页
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
关键词 pinning control projective synchronization drive system response network
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Current status and diversity of fish resources in the Pinglu Canal Century Project
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作者 LU Jia TANG Wei +3 位作者 WANG Li XU Shengxian ZHANG Peng YANG Shengfa 《水利水电技术(中英文)》 北大核心 2025年第4期131-144,共14页
[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
关键词 Pinglu Canal project inter-basin connectivity fish resources community structure BIODIVERSITY influencing factors
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Lightweight deep network and projection loss for eye semantic segmentation
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作者 Qinjie Wang Tengfei Wang +1 位作者 Lizhuang Yang Hai Li 《中国科学技术大学学报》 北大核心 2025年第7期59-68,58,I0002,共12页
Semantic segmentation of eye images is a complex task with important applications in human–computer interaction,cognitive science,and neuroscience.Achieving real-time,accurate,and robust segmentation algorithms is cr... Semantic segmentation of eye images is a complex task with important applications in human–computer interaction,cognitive science,and neuroscience.Achieving real-time,accurate,and robust segmentation algorithms is crucial for computationally limited portable devices such as augmented reality and virtual reality.With the rapid advancements in deep learning,many network models have been developed specifically for eye image segmentation.Some methods divide the segmentation process into multiple stages to achieve model parameter miniaturization while enhancing output through post processing techniques to improve segmentation accuracy.These approaches significantly increase the inference time.Other networks adopt more complex encoding and decoding modules to achieve end-to-end output,which requires substantial computation.Therefore,balancing the model’s size,accuracy,and computational complexity is essential.To address these challenges,we propose a lightweight asymmetric UNet architecture and a projection loss function.We utilize ResNet-3 layer blocks to enhance feature extraction efficiency in the encoding stage.In the decoding stage,we employ regular convolutions and skip connections to upscale the feature maps from the latent space to the original image size,balancing the model size and segmentation accuracy.In addition,we leverage the geometric features of the eye region and design a projection loss function to further improve the segmentation accuracy without adding any additional inference computational cost.We validate our approach on the OpenEDS2019 dataset for virtual reality and achieve state-of-the-art performance with 95.33%mean intersection over union(mIoU).Our model has only 0.63M parameters and 350 FPS,which are 68%and 200%of the state-of-the-art model RITNet,respectively. 展开更多
关键词 lightweight deep network projection loss real-time semantic segmentation convolutional neural networks END-TO-END
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