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Trends in alpha diversity,community composition,and network complexity of rare,intermediate,and abundant bacterial taxa along a latitudinal gradient and their impact on ecosystem multifunctionality
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作者 Rong Tang Shuaifeng Li +3 位作者 Xiaobo Huang Rui Zhang Cong Li Jianrong Su 《Forest Ecosystems》 2025年第4期642-654,共13页
Soil microbial communities are key factors in maintaining ecosystem multifunctionality(EMF).However,the distribution patterns of bacterial diversity and how the different bacterial taxa and their diversity dimensions ... Soil microbial communities are key factors in maintaining ecosystem multifunctionality(EMF).However,the distribution patterns of bacterial diversity and how the different bacterial taxa and their diversity dimensions affect EMF remain largely unknown.Here,we investigated variation in three measures of diversity(alpha diversity,community composition and network complexity)among rare,intermediate,and abundant taxa across a latitudinal gradient spanning five forest plots in Yunnan Province,China and examined their contributions on EMF.We aimed to characterize the diversity distributions of bacterial groups across latitudes and to assess the differences in the mechanisms underlying their contributions to EMF.We found that multifaceted diversity(i.e.,diversity assessed by the three different metrics)of rare,intermediate,and abundant bacteria generally decreased with increasing latitude.More importantly,we found that rare bacterial taxa tended to be more diverse,but they contributed less to EMF than intermediate or abundant bacteria.Among the three dimensions of diversity we assessed,only community composition significantly affected EMF across all locations,while alpha diversity had a negative effect,and network complexity showed no significant impact.Our study further emphasizes the importance of intermediate and abundant bacterial taxa as well as community composition to EMF and provides a theoretical basis for investigating the mechanisms by which belowground microorganisms drive EMF along a latitudinal gradient. 展开更多
关键词 BACTERIA Ecosystem multifunctionality Alpha diversity Community composition Network complexity Latitudinal gradient
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Performance vs.Complexity Comparative Analysis of Multimodal Bilinear Pooling Fusion Approaches for Deep Learning-Based Visual Arabic-Question Answering Systems
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作者 Sarah M.Kamel Mai A.Fadel +1 位作者 Lamiaa Elrefaei Shimaa I.Hassan 《Computer Modeling in Engineering & Sciences》 2025年第4期373-411,共39页
Visual question answering(VQA)is a multimodal task,involving a deep understanding of the image scene and the question’s meaning and capturing the relevant correlations between both modalities to infer the appropriate... Visual question answering(VQA)is a multimodal task,involving a deep understanding of the image scene and the question’s meaning and capturing the relevant correlations between both modalities to infer the appropriate answer.In this paper,we propose a VQA system intended to answer yes/no questions about real-world images,in Arabic.To support a robust VQA system,we work in two directions:(1)Using deep neural networks to semantically represent the given image and question in a fine-grainedmanner,namely ResNet-152 and Gated Recurrent Units(GRU).(2)Studying the role of the utilizedmultimodal bilinear pooling fusion technique in the trade-o.between the model complexity and the overall model performance.Some fusion techniques could significantly increase the model complexity,which seriously limits their applicability for VQA models.So far,there is no evidence of how efficient these multimodal bilinear pooling fusion techniques are for VQA systems dedicated to yes/no questions.Hence,a comparative analysis is conducted between eight bilinear pooling fusion techniques,in terms of their ability to reduce themodel complexity and improve themodel performance in this case of VQA systems.Experiments indicate that these multimodal bilinear pooling fusion techniques have improved the VQA model’s performance,until reaching the best performance of 89.25%.Further,experiments have proven that the number of answers in the developed VQA system is a critical factor that a.ects the effectiveness of these multimodal bilinear pooling techniques in achieving their main objective of reducing the model complexity.The Multimodal Local Perception Bilinear Pooling(MLPB)technique has shown the best balance between the model complexity and its performance,for VQA systems designed to answer yes/no questions. 展开更多
关键词 Arabic-VQA deep learning-based VQA deep multimodal information fusion multimodal representation learning VQA of yes/no questions VQA model complexity VQA model performance performance-complexity trade-off
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Exploring the Effects of Background Image Complexity and Map Symbol Load on the Usability of Image-maps 被引量:1
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作者 PENG Qian XIA Yuxin QIU Zeren 《Journal of Geodesy and Geoinformation Science》 2025年第2期5-20,共16页
Image-maps,a hybrid design with satellite images as background and map symbols uploaded,aim to combine the advantages of maps’high interpretation efficiency and satellite images’realism.The usability of image-maps i... Image-maps,a hybrid design with satellite images as background and map symbols uploaded,aim to combine the advantages of maps’high interpretation efficiency and satellite images’realism.The usability of image-maps is influenced by the representations of background images and map symbols.Many researchers explored the optimizations for background images and symbolization techniques for symbols to reduce the complexity of image-maps and improve the usability.However,little literature was found for the optimum amount of symbol loading.This study focuses on the effects of background image complexity and map symbol load on the usability(i.e.,effectiveness and efficiency)of image-maps.Experiments were conducted by user studies via eye-tracking equipment and an online questionnaire survey.Experimental data sets included image-maps with ten levels of map symbol load in ten areas.Forty volunteers took part in the target searching experiments.It has been found that the usability,i.e.,average time viewed(efficiency)and average revisits(effectiveness)of targets recorded,is influenced by the complexity of background images,a peak exists for optimum symbol load for an image-map.The optimum levels for symbol load for different image-maps also have a peak when the complexity of the background image/image map increases.The complexity of background images serves as a guideline for optimum map symbol load in image-map design.This study enhanced user experience by optimizing visual clarity and managing cognitive load.Understanding how these factors interact can help create adaptive maps that maintain clarity and usability,guiding AI algorithms to adjust symbol density based on user context.This research establishes the practices for map design,making cartographic tools more innovative and more user-centric. 展开更多
关键词 remote sensing image map point label complexity
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Smart cities,smart systems:A comprehensive review of system dynamics model applications in urban studies in the big data era 被引量:1
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作者 Gift Fabolude Charles Knoble +1 位作者 Anvy Vu Danlin Yu 《Geography and Sustainability》 2025年第1期25-36,共12页
This paper addresses urban sustainability challenges amid global urbanization, emphasizing the need for innova tive approaches aligned with the Sustainable Development Goals. While traditional tools and linear models ... This paper addresses urban sustainability challenges amid global urbanization, emphasizing the need for innova tive approaches aligned with the Sustainable Development Goals. While traditional tools and linear models offer insights, they fall short in presenting a holistic view of complex urban challenges. System dynamics (SD) models that are often utilized to provide holistic, systematic understanding of a research subject, like the urban system, emerge as valuable tools, but data scarcity and theoretical inadequacy pose challenges. The research reviews relevant papers on recent SD model applications in urban sustainability since 2018, categorizing them based on nine key indicators. Among the reviewed papers, data limitations and model assumptions were identified as ma jor challenges in applying SD models to urban sustainability. This led to exploring the transformative potential of big data analytics, a rare approach in this field as identified by this study, to enhance SD models’ empirical foundation. Integrating big data could provide data-driven calibration, potentially improving predictive accuracy and reducing reliance on simplified assumptions. The paper concludes by advocating for new approaches that reduce assumptions and promote real-time applicable models, contributing to a comprehensive understanding of urban sustainability through the synergy of big data and SD models. 展开更多
关键词 Urban sustainability Smart cities system dynamics models Big data analytics Urban system complexity Data-driven urbanism
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Diversity,Complexity,and Challenges of Viral Infectious Disease Data in the Big Data Era:A Comprehensive Review 被引量:1
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作者 Yun Ma Lu-Yao Qin +1 位作者 Xiao Ding Ai-Ping Wu 《Chinese Medical Sciences Journal》 2025年第1期29-44,I0005,共17页
Viral infectious diseases,characterized by their intricate nature and wide-ranging diversity,pose substantial challenges in the domain of data management.The vast volume of data generated by these diseases,spanning fr... Viral infectious diseases,characterized by their intricate nature and wide-ranging diversity,pose substantial challenges in the domain of data management.The vast volume of data generated by these diseases,spanning from the molecular mechanisms within cells to large-scale epidemiological patterns,has surpassed the capabilities of traditional analytical methods.In the era of artificial intelligence(AI)and big data,there is an urgent necessity for the optimization of these analytical methods to more effectively handle and utilize the information.Despite the rapid accumulation of data associated with viral infections,the lack of a comprehensive framework for integrating,selecting,and analyzing these datasets has left numerous researchers uncertain about which data to select,how to access it,and how to utilize it most effectively in their research.This review endeavors to fill these gaps by exploring the multifaceted nature of viral infectious diseases and summarizing relevant data across multiple levels,from the molecular details of pathogens to broad epidemiological trends.The scope extends from the micro-scale to the macro-scale,encompassing pathogens,hosts,and vectors.In addition to data summarization,this review thoroughly investigates various dataset sources.It also traces the historical evolution of data collection in the field of viral infectious diseases,highlighting the progress achieved over time.Simultaneously,it evaluates the current limitations that impede data utilization.Furthermore,we propose strategies to surmount these challenges,focusing on the development and application of advanced computational techniques,AI-driven models,and enhanced data integration practices.By providing a comprehensive synthesis of existing knowledge,this review is designed to guide future research and contribute to more informed approaches in the surveillance,prevention,and control of viral infectious diseases,particularly within the context of the expanding big-data landscape. 展开更多
关键词 viral infectious diseases big data data diversity and complexity data standardization artificial intelligence data analysis
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Data-Driven Prediction in Complex Systems of Virus Evolution and Global Warming 被引量:1
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作者 LUO Liaofu LÜJun 《内蒙古大学学报(自然科学版)》 2025年第1期1-7,共7页
A complex system is inherently high-dimensional.Recent studies indicate that,even without complete knowledge of its evolutionary dynamics,the future behavior of such a system can be predicted using time-series data(da... A complex system is inherently high-dimensional.Recent studies indicate that,even without complete knowledge of its evolutionary dynamics,the future behavior of such a system can be predicted using time-series data(data-driven prediction).This suggests that the essential dynamics of a complex system can be captured through a low-dimensional representation.Virus evolution and climate change are two examples of complex,time-varying systems.In this article,we show that mutations in the spike protein provide valuable data for predicting SARS-CoV-2 variants,forecasting the possible emergence of the new macro-lineage Q in the near future.Our analysis also demonstrates that carbon dioxide concentration is a reliable indicator for predicting the evolution of the climate system,extending global surface air temperature(GSAT)forecasts through 2500. 展开更多
关键词 data-drivenprediction complex system virus evolution global warming
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CNKSR2 interactome analysis indicates its association with the centrosome/microtubule system
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作者 Lin Yin Yalan Xu +9 位作者 Jie Mu Yu Leng Lei Ma Yu Zheng Ruizhi Li Yin Wang Peifeng Li Hai Zhu Dong Wang Jing Li 《Neural Regeneration Research》 SCIE CAS 2025年第8期2420-2432,共13页
The protein connector enhancer of kinase suppressor of Ras 2(CNKSR2),present in both the postsynaptic density and cytoplasm of neurons,is a scaffolding protein with several protein-binding domains.Variants of the CNKS... The protein connector enhancer of kinase suppressor of Ras 2(CNKSR2),present in both the postsynaptic density and cytoplasm of neurons,is a scaffolding protein with several protein-binding domains.Variants of the CNKSR2 gene have been implicated in neurodevelopmental disorders,particularly intellectual disability,although the precise mechanism involved has not yet been fully understood.Research has demonstrated that CNKSR2 plays a role in facilitating the localization of postsynaptic density protein complexes to the membrane,thereby influencing synaptic signaling and the morphogenesis of dendritic spines.However,the function of CNKSR2 in the cytoplasm remains to be elucidated.In this study,we used immunoprecipitation and high-resolution liquid chromatography-mass spectrometry to identify the interactors of CNKSR2.Through a combination of bioinformatic analysis and cytological experiments,we found that the CNKSR2 interactors were significantly enriched in the proteome of the centrosome.We also showed that CNKSR2 interacted with the microtubule protein DYNC1H1 and with the centrosome marker CEP290.Subsequent colocalization analysis confirmed the centrosomal localization of CNKSR2.When we downregulated CNKSR2 expression in mouse neuroblastoma cells(Neuro 2A),we observed significant changes in the expression of numerous centrosomal genes.This manipulation also affected centrosome-related functions,including cell size and shape,cell proliferation,and motility.Furthermore,we found that CNKSR2 interactors were highly enriched in de novo variants associated with intellectual disability and autism spectrum disorder.Our findings establish a connection between CNKSR2 and the centrosome,and offer new insights into the underlying mechanisms of neurodevelopmental disorders. 展开更多
关键词 autism spectrum disorder CENTROSOME CNKSR2 intellectual disability INTERACTOME mass spectrometry MICROTUBULE neurodevelopmental disease protein complexes protein-protein interactions
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Functions of nuclear factor Y in nervous system development,function and health
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作者 Pedro Moreira Roger Pocock 《Neural Regeneration Research》 SCIE CAS 2025年第10期2887-2894,共8页
Nuclear factor Y is a ubiquitous heterotrimeric transcription factor complex conserved across eukaryotes that binds to CCAAT boxes,one of the most common motifs found in gene promoters and enhancers.Over the last 30 y... Nuclear factor Y is a ubiquitous heterotrimeric transcription factor complex conserved across eukaryotes that binds to CCAAT boxes,one of the most common motifs found in gene promoters and enhancers.Over the last 30 years,research has revealed that the nuclear factor Y complex controls many aspects of brain development,including differentiation,axon guidance,homeostasis,disease,and most recently regeneration.However,a complete understanding of transcriptional regulatory networks,including how the nuclear factor Y complex binds to specific CCAAT boxes to perform its function remains elusive.In this review,we explore the nuclear factor Y complex’s role and mode of action during brain development,as well as how genomic technologies may expand understanding of this key regulator of gene expression. 展开更多
关键词 axon guidance CCAAT boxes neuronal degeneration neuronal differentiation neuronal regeneration nuclear factor Y complex transcription factor transcriptional regulation
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Multiscale structural complexity analysis of neuronal activity in suprachiasmatic nucleus:Insights from tetrodotoxin-induced disruptions
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作者 Ping Wang Changgui Gu Huijie Yang 《Chinese Physics B》 2025年第4期605-613,共9页
The suprachiasmatic nucleus in the hypothalamus is the master circadian clock in mammals,coordinating physiological processes with the 24-hour day–night cycle.Comprising various cell types,the suprachiasmatic nucleus... The suprachiasmatic nucleus in the hypothalamus is the master circadian clock in mammals,coordinating physiological processes with the 24-hour day–night cycle.Comprising various cell types,the suprachiasmatic nucleus(SCN)integrates environmental signals to maintain complex and robust circadian rhythms.Understanding the complexity and synchrony within SCN neurons is essential for effective circadian clock function.Synchrony involves coordinated neuronal firing for robust rhythms,while complexity reflects diverse activity patterns and interactions,indicating adaptability.Interestingly,the SCN retains circadian rhythms in vitro,demonstrating intrinsic rhythmicity.This study introduces the multiscale structural complexity method to analyze changes in SCN neuronal activity and complexity at macro and micro levels,based on Bagrov et al.’s approach.By examining structural complexity and local complexities across scales,we aim to understand how tetrodotoxin,a neurotoxin that inhibits action potentials,affects SCN neurons.Our method captures critical scales in neuronal interactions that traditional methods may overlook.Validation with the Goodwin model confirms the reliability of our observations.By integrating experimental data with theoretical models,this study provides new insights into the effects of tetrodotoxin(TTX)on neuronal complexities,contributing to the understanding of circadian rhythms. 展开更多
关键词 suprachiasmatic nucleus circadian rhythm complexity synchrony multiscale structural complexity
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Quantum Dynamics of Complex Systems
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作者 Xiang Sun 《Chinese Journal of Chemical Physics》 2025年第4期373-374,共2页
The ability to accurately simulate the time evolu-tion of quantum systems stands as a cornerstone of modern molecular science.It provides the essential mechanistic bridge between a system’s microscopic structure and ... The ability to accurately simulate the time evolu-tion of quantum systems stands as a cornerstone of modern molecular science.It provides the essential mechanistic bridge between a system’s microscopic structure and its macroscopic function,a challenge first envisioned by Feynman.The central difficulty,and the unifying theme of this Special Topic,is the problem of“complexity”:a multifaceted challenge arising from the interplay of strongly coupled electronic and vibrational degrees of freedom,quantum statistics,and the non-trivial,often non-Markovian,memory effects exerted by a surrounding environment. 展开更多
关键词 electronic vibrational degrees freedomquantum statistic quantum dynamics complex systems FEYNMAN electronic degrees freedom complexity molecular science mechanistic bridge
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Navigating anatomical complexity in laparoscopic sigmoid cancer surgery:A three-dimension reconstruction protocol for intraoperative safety and efficiency
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作者 Zong-Xian Zhao Run-Dong Yao +3 位作者 Zong-Ju Hu Chao-Qian Chen Shu Zhu Yuan Yao 《World Journal of Gastrointestinal Surgery》 2025年第8期350-361,共12页
BACKGROUND Sigmoid colon cancer faces challenges due to anatomical diversity,including variable inferior mesenteric artery(IMA)branching and tumor localization complexities,which increase intraoperative risks.AIM To c... BACKGROUND Sigmoid colon cancer faces challenges due to anatomical diversity,including variable inferior mesenteric artery(IMA)branching and tumor localization complexities,which increase intraoperative risks.AIM To comprehensively evaluate the impact of three-dimensional(3D)visualization technology on enhancing surgical precision and safety,as well as optimizing perioperative outcomes in laparoscopic sigmoid cancer resection.METHODS A prospective cohort of 106 patients(January 2023 to December 2024)undergoing laparoscopic sigmoid cancer resection was divided into the 3D(n=55)group and the control(n=51)group.The 3D group underwent preoperative enhanced computed tomography reconstruction(3D Slicer 5.2.2&Mimics 19.0).3D reconstruction visualization navigation intraoperatively guided the following key steps:Tumor location,Toldt’s space dissection,IMA ligation level selection,regional lymph node dissection,and marginal artery preservation.Outcomes included operative parameters,lymph node yield,and recovery metrics.RESULTS The 3D group demonstrated a significantly shorter operative time(172.91±20.69 minutes vs 190.29±32.29 minutes;P=0.002),reduced blood loss(31.5±11.8 mL vs 44.1±23.4 mL,P=0.001),earlier postoperative flatus(2.23±0.54 days vs 2.53±0.61 days;P=0.013),shorter hospital length of stay(13.47±1.74 days vs 16.20±7.71 days;P=0.013),shorter postoperative length of stay(8.6±2.6 days vs 10.5±4.9 days;P=0.014),and earlier postoperative exhaust time(2.23±0.54 days vs 2.53±0.61 days;P=0.013).Furthermore,the 3D group exhibited a higher mean number of lymph nodes harvested(16.91±5.74 vs 14.45±5.66;P=0.030).CONCLUSION The 3D visualization technology effectively addresses sigmoid colon anatomical complexity through surgical navigation,improving procedural safety and efficiency. 展开更多
关键词 Three-dimension reconstruction Sigmoid colon cancer Visualization Inferior mesenteric artery Anatomical complexity Intraoperative safety
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The role of psychological meaningfulness in the relationship between job complexity and work-family conflict among secondary school teachers in Nigeria
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作者 Gabriel C.Kanu Noah Adeji +3 位作者 Tobias C.Obi Elom S.Omena Raphael U.Anike Alexander U.Amaechi 《Journal of Psychology in Africa》 2025年第1期1-5,共5页
This study examined how psychological meaningfulness moderates job complexity and work-family conflict in Nigerian secondary school teachers.This study included 1694 teachers from 17 Nigerian secondary schools(female=6... This study examined how psychological meaningfulness moderates job complexity and work-family conflict in Nigerian secondary school teachers.This study included 1694 teachers from 17 Nigerian secondary schools(female=69.54%,mean age=33.19,SD=6.44 years).The participants completed the Work-family Conflict Scale,Job Complexity Scale,and Psychological Meaningfulness Scale.Study design was cross-sectional.Hayes PROCESS macro analysis results indicate a higher work-family conflict with job complexity among the secondary school teachers.While psychological meaningfulness was not associated with work-family conflict,it moderated the link between job complexity and work-family conflict in secondary school teachers such that a meaningful work endorsement is associated with lower employee’s work-life conflict.Thesefindings point to the importance of job functions to quality of family life.The studyfindings also suggest a need for supporting psychological meaningfulness for healthy work related quality of family life based on balancing work and family role demands. 展开更多
关键词 psychological meaningfulness job complexity work-family conflict secondary school TEACHERS
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Corrigendum to"Topographic complexity drives trait composition as well as functional and phylogenetic diversity of understory plant communities in microrefugia:New insights for conservation"[Forest Ecosyst.12(2025)100278]
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作者 Kata Frei Anna E-Vojtkó +6 位作者 Csaba Tölgyesi András Vojtkó Tünde Farkas LászlóErdős Gábor Li Ádám Lőrincz Zoltán Bátori 《Forest Ecosystems》 2025年第3期536-538,共3页
The authors regret that an error occurred during the preparation of their article:One of the official databases,which was used for functional trait collections,contained an incorrect term–'chametophytes'–for... The authors regret that an error occurred during the preparation of their article:One of the official databases,which was used for functional trait collections,contained an incorrect term–'chametophytes'–for the life form category'chamaephytes'.Unfortunately,this incorrect term was used throughout the article following the nomenclature of this official database:in one instance in the main text,in Fig.3 and its caption,in Fig.5,and in two instances in the supplementary material. 展开更多
关键词 functional diversity functional trait collectionscontained understory plant communities supplementary material phylogenetic diversity CORRIGENDUM topographic complexity official database
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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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The 2-adic complexity of sum sequences of Legendre sequences
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作者 JING Xiaoyan XU Zhefeng FENG Keqin 《纯粹数学与应用数学》 2025年第2期191-199,共9页
Binary sequences constructed by Legendre symbols are widely used in communication and cryptography since they have many good pseudo-random properties.In this paper,we determine the 2-adic complexity of the sum sequenc... Binary sequences constructed by Legendre symbols are widely used in communication and cryptography since they have many good pseudo-random properties.In this paper,we determine the 2-adic complexity of the sum sequence of any k many Legendre sequences and show that the 2-adic complexity of the sum sequences of any k many Legendre sequences reaches the maximum by proving the case of k=2 and 3,which implies that the sum sequences can resist the attack of rational approximation algorithm. 展开更多
关键词 2-adic complexity binary sequences Legendre symbol Legendre sequences
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Direct identification of energy transfer mechanism in Ce^(Ⅲ)-Mn^(Ⅱ)system by constructing molecular heteronuclear complexes
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作者 Huanyu Liu Gang Yu +6 位作者 Ruoyao Guo Hao Qi Jiayin Zheng Tong Jin Zifeng Zhao Zuqiang Bian Zhiwei Liu 《Chinese Chemical Letters》 2025年第2期156-160,共5页
Sensitization of metal-centered forbidden transitions is of great significance.Solid MnII-based phosphors with d-d forbidden transition sensitized by CeIIIwith d-f allowed transition are promising light conversion mat... Sensitization of metal-centered forbidden transitions is of great significance.Solid MnII-based phosphors with d-d forbidden transition sensitized by CeIIIwith d-f allowed transition are promising light conversion materials,but the energy transfer mechanism in CeIII-MnIIis still in dispute for the uncertainty of distances between metal centers.Herein,for the first time,we explored the energy transfer mechanism in two well-designed luminescent heteronuclear complexes with clear crystal structures,i.e.,Ce-N8-Mn and Ce-N2O6-Mn(N8=1,4,7,10,13,16,21,24-octaazabicyclo[8.8.8]hexacosane;N2O6=4,7,13,16,21,24-hexaoxa-1,10-diazabicyclo[8.8.8]hexacosane).Short distances between metal centers facilitate efficient energy transfer from CeIIIto MnIIin both complexes,resulting in high photoluminescence quantum yield up to unity.After systematic study of the two heteronuclear complexes as well as two reference complexes Ce(N8)Br3and Ce(N2O6)Br3,we concluded that dipole-quadrupole interaction is the dominant energy transfer mechanism in the heteronuclear complexes. 展开更多
关键词 Dipole-quadrupole interaction Förster resonance energy transfer Manganese complex Cerium complex PHOTOLUMINESCENCE
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Outbreaks of Ulva prolifera green tides reduce the network complexity and stability of cooccurring planktonic microbial communities
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作者 Honglei Zhang Hui He +8 位作者 Feilong Liu Can Wang Kaiyue Lian Chuyu Zhang Yi Li Bo Wang Andrew McMinn Hualong Wang Min Wang 《Journal of Environmental Sciences》 2025年第8期15-30,共16页
Ulva prolifera green tides are becoming aworldwide environmental problem,especially in the Yellow Sea,China.However,the effects of the occurrence of U.prolifera green tides on the community organization and stability ... Ulva prolifera green tides are becoming aworldwide environmental problem,especially in the Yellow Sea,China.However,the effects of the occurrence of U.prolifera green tides on the community organization and stability of surrounding microbiomes have still not been de-termined.Here,the prokaryotic microbial community network stability and assembly char-acteristics were systematically analyzed and compared between the green tide and non-green tide periods.U.prolifera blooms weaken the community complexity and robustness of surrounding microbiomes,increasing fragmentation and decreasing diversity.Bacteria and archaea exhibited distinct community distributions and assembly patterns under the influ-ence of green tides,and bacterial communities were more sensitive to outbreaks of green tides.The bacterial communities exhibited a greater niche breadth and a lower phyloge-netic distance during the occurrence of U.prolifera green tides compared to those during the non-green tide period while archaeal communities remained unchanged,suggesting that the bacterial communities underwent stronger homogeneous selection and more sensitive to green tide blooms than the archaeal communities.Piecewise structural equation model analysis revealed that the different responses of major prokaryotic microbial groups,such as Cyanobacteria,to environmental variables during green tides,were influenced by the variations in pH and nitrate during green tides and correlated with the salinity gradient during the non-green tide period.This study elucidates the response of the adaptability,associations,and stability of surrounding microbiomes to outbreaks of U.prolifera green tides. 展开更多
关键词 Ulva prolifera green tide Prokaryotic microbial communities Assembly process Community complexity Cooccurrence stability
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Low-complexity multi-target localization via multi-BS sensing
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作者 Yinxiao Zhuo Zhaocheng Wang 《Digital Communications and Networks》 2025年第4期1140-1148,共9页
Integrated Sensing and Communication(ISAC)is envisioned as a promising technology for Sixth-Generation(6G)wireless communications,which enables simultaneous high-rate communication and high-precision target localizati... Integrated Sensing and Communication(ISAC)is envisioned as a promising technology for Sixth-Generation(6G)wireless communications,which enables simultaneous high-rate communication and high-precision target localization.Compared to independent sensing and communication modules,dual-function ISAC could leverage the strengths of both communication and sensing in order to achieve cooperative gains.When considering the communication core network,ISAC system facilitates multiple communication devices to collaborate for networked sensing.This paper investigates such kind of cooperative ISAC systems with distributed transmitters and receivers to support non-connected and multi-target localization.Specifically,we introduce a Time of Arrival(TOA)based multi-target localization scheme,which leverages the bi-static range measurements between the transmitter,target,and receiver channels in order to achieve elliptical localization.To obtain the low-complexity localization,a two-stage search-refine localization methodology is proposed.In the first stage,we propose a Successive Greedy Grid-Search(SGGS)algorithm and a Successive-Cancellation-List Grid-Search(SCLGS)algorithm to address the Measurement-to-Target Association(MTA)problem with relatively low computational complexity.In the second stage,a linear approximation refinement algorithm is derived to facilitate high-precision localization.Simulation results are presented to validate the effectiveness and superiority of our proposed multi-target localization method. 展开更多
关键词 Integrated sensing and communication Multi-target localization Measurement-to-target association problem Bi-static range measurement Low complexity
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Decoupling of diversity and network complexity of bacterial communities during water quality deterioration
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作者 Qiuyue Feng Yuyan Liu +6 位作者 Kaiming Hu Guanghui Wang Zhiquan Liu Yu Han Wenbing Li Hangjun Zhang Binhao Wang 《Journal of Environmental Sciences》 2025年第9期86-95,共10页
Numerous studies have examined the impact ofwater quality degradation on bacterial community structure,yet insights into its effects on the bacterial ecological networks remain scarce.In this study,we investigated the... Numerous studies have examined the impact ofwater quality degradation on bacterial community structure,yet insights into its effects on the bacterial ecological networks remain scarce.In this study,we investigated the diversity,composition,assembly patterns,ecological networks,and environmental determinants of bacterial communities across 20 ponds to understand the impact of water quality degradation.Our findings revealed that water quality degradation significantly reduces the α-diversity of bacterial communities in water samples,while sediment samples remain unaffected.Additionally,water quality deterioration increases the complexity of bacterial networks in water samples but reduces it in sediment samples.These shifts in bacterial communities were primarily governed by deterministic processes,with heterogeneous selection being particularly influential.Through redundancy analysis(RDA),multiple regression on matrices(MRM),and Mantel tests,we identified dissolved oxygen(DO),ammonium nitrogen(NH_(4)^(+)-N),and C/N ratio as key factors affecting the composition and network complexity of bacterial communities in both water and sediment.Overall,this study contributes a novel perspective on the effect ofwater quality deterioration on microbial ecosystems and provides valuable insights for improving ecological evaluations and biomonitoring practices related to water quality management. 展开更多
关键词 Water quality degradation Bacterial communities Network complexity Driving factors
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Diversity and Complexity of Soil Organic Carbon in Typical Wetlands of Louisiana,USA
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作者 YU Lu JIANG Qijun +2 位作者 ZHAO Wenwen ZHANG Zhongsheng WANG Jim Jian 《Chinese Geographical Science》 2025年第2期415-422,共8页
Coastal wetlands store large amounts of soil organic carbon(SOC),and have assumed key roles in mitigating increasing CO_(2)in the atmosphere.The ongoing debate about SOC stabilization mechanisms stems partly from our ... Coastal wetlands store large amounts of soil organic carbon(SOC),and have assumed key roles in mitigating increasing CO_(2)in the atmosphere.The ongoing debate about SOC stabilization mechanisms stems partly from our incomplete understanding of its complex chemical architecture at the molecular scale.Deciphering the molecular composition of soil organic matter is crucial for revealing mechanisms that govern SOC persistence.This study utilized the field sampling data from 2016 and aimed to characterize molecular composition of SOC in typical salt marsh(SM)and freshwater marsh(FM)in Louisiana coastal regions,USA by extending the application of graph networks with pyrolysis-gas chromatography-mass spectrometry,and then to quantify potential links between SOC persistence and molecular diversity and network complexity.The results revealed that SOC predominantly consisted of alkyl compounds(Alkyl),phenol(Ph),lignin(Lg),and aliphatic compounds,constituting 23.21%and 27.85%,17.84%and 21.55%,16.94%and 15.49%,17.20%and 15.93%of total ion chromatogram(TIC)in SM and FM wetlands,respectively.Molecular diversity in SM was higher than that in FM,while the network graph exhibited greater complexity in FM,featuring 167 and 123 nodes,and 1935 and 1982 edges in the network graphs of SOC from SM and FM,respectively.Correlation analysis confirmed positive relations between molecular diversity indices,network complexity,and abundance of stable carbon isotopes(δ^(13)C).The variance partitioning analysis(VPA)supplied that soil nutrients exerted the most significant control on SOC persistence.Molecular diversity and network complexity,when combined with soil nutrients,could explain 34%of the variances in SOC persistence. 展开更多
关键词 soil organic matter pyrolysis-gas chromatography/mass spectrometry(Py-GC/MS) molecular diversity network complexity coastal wetlands Louisiana USA
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