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Research on the Principle Comparison and Comprehensive Application of High-Availability Clusters and Load-Balancing Clusters
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作者 Yue Yang 《Journal of Electronic Research and Application》 2025年第6期294-301,共8页
In modern distributed systems and cloud computing architectures,high availability and high scalability are core requirements to ensure the continuous and stable operation of services.As key technologies for achieving ... In modern distributed systems and cloud computing architectures,high availability and high scalability are core requirements to ensure the continuous and stable operation of services.As key technologies for achieving these two goals,high-availability clusters and load-balancing clusters have significant differences in their design concepts and application scenarios,while also maintaining close connections.This paper aims to conduct an in-depth analysis of the core objectives,working principles,technical advantages and disadvantages,and typical application cases of high-availability clusters and load-balancing clusters.By introducing an analogical model of a“restaurant kitchen,”the differences between the two are intuitively explained,and their technical characteristics are compared in detail.Additionally,a detailed practical case is included to specifically demonstrate the collaborative work of high-availability and load-balancing technologies through the construction process of Keepalived and HAProxy.Finally,taking the architecture of a typical e-commerce website as an example,this paper demonstrates the best practice of organically combining the two cluster technologies in a production environment to build a robust and high-performance distributed system.Research shows that understanding the differences between the two and implementing collaborative deployment is the cornerstone of designing modern IT infrastructure. 展开更多
关键词 High-availability cluster load-balancing cluster Failover Distributed system Architecture design Performance optimization
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Combined Fault Tree Analysis and Bayesian Network for Reliability Assessment of Marine Internal Combustion Engine
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作者 Ivana Jovanović Çağlar Karatuğ +1 位作者 Maja Perčić Nikola Vladimir 《哈尔滨工程大学学报(英文版)》 2026年第1期239-258,共20页
This paper investigates the reliability of internal marine combustion engines using an integrated approach that combines Fault Tree Analysis(FTA)and Bayesian Networks(BN).FTA provides a structured,top-down method for ... This paper investigates the reliability of internal marine combustion engines using an integrated approach that combines Fault Tree Analysis(FTA)and Bayesian Networks(BN).FTA provides a structured,top-down method for identifying critical failure modes and their root causes,while BN introduces flexibility in probabilistic reasoning,enabling dynamic updates based on new evidence.This dual methodology overcomes the limitations of static FTA models,offering a comprehensive framework for system reliability analysis.Critical failures,including External Leakage(ELU),Failure to Start(FTS),and Overheating(OHE),were identified as key risks.By incorporating redundancy into high-risk components such as pumps and batteries,the likelihood of these failures was significantly reduced.For instance,redundant pumps reduced the probability of ELU by 31.88%,while additional batteries decreased the occurrence of FTS by 36.45%.The results underscore the practical benefits of combining FTA and BN for enhancing system reliability,particularly in maritime applications where operational safety and efficiency are critical.This research provides valuable insights for maintenance planning and highlights the importance of redundancy in critical systems,especially as the industry transitions toward more autonomous vessels. 展开更多
关键词 Fault tree analysis Bayesian network RELIABILITY REDUNDANCY Internal combustion engine
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Load-balancing data distribution in publish/subscribe mode
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作者 李凯 汪芸 +1 位作者 殷奕 袁飞飞 《Journal of Southeast University(English Edition)》 EI CAS 2014年第4期428-433,共6页
To improve data distribution efficiency a load-balancing data distribution LBDD method is proposed in publish/subscribe mode.In the LBDD method subscribers are involved in distribution tasks and data transfers while r... To improve data distribution efficiency a load-balancing data distribution LBDD method is proposed in publish/subscribe mode.In the LBDD method subscribers are involved in distribution tasks and data transfers while receiving data themselves.A dissemination tree is constructed among the subscribers based on MD5 where the publisher acts as the root. The proposed method provides bucket construction target selection and path updates furthermore the property of one-way dissemination is proven.That the average out-going degree of a node is 2 is guaranteed with the proposed LBDD.The experiments on data distribution delay data distribution rate and load distribution are conducted. Experimental results show that the LBDD method aids in shaping the task load between the publisher and subscribers and outperforms the point-to-point approach. 展开更多
关键词 data distribution publish/subscribe mode load balance dissemination tree
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AN ADVANCED DYNAMIC FEEDBACK AND RANDOM DISPATCHING LOAD-BALANCING ALGORITHM FOR GMLC IN 3G 被引量:1
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作者 Liao Jianxin Zhang Hao Zhu Xiaomin 《Journal of Electronics(China)》 2006年第5期641-644,共4页
Based on the system architecture and software structure of GMLC (Gateway Mobile Location Center) in 3G (third generation), a new dynamic load-balancing algorithm is proposed. It bases on dynamic feedback and imports t... Based on the system architecture and software structure of GMLC (Gateway Mobile Location Center) in 3G (third generation), a new dynamic load-balancing algorithm is proposed. It bases on dynamic feedback and imports the increment for admitting new request into the load forecast. It dynamically adjusts the dispatching probability according to the remainder process capability of each node. Experiments on the per- formance of algorithm have been carried out in GMLC and the algorithm is compared with Pick-KX algorithm and DFB (Dynamic FeedBack) algorithm in average throughput and average response time. Experiments re- sults show that the average throughput of the proposed algorithm is about five percents higher than that of the other two algorithms and the average response time is four percents higher under high system loading condi- tion. 展开更多
关键词 GMLC (Gateway Mobile Location Center) load-balancing algorithm Heterogeneous cluster
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A LIMITED RESOURCE VECTOR LOAD-BALANCING ALGORITHM FOR SOFTSWITCH-BASED HETEROGENEOUS CLUSTERED MEDIA SERVER
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作者 Wu Naixing Liao Jianxin Zhu Xiaomin 《Journal of Electronics(China)》 2006年第5期683-690,共8页
Based on the system feature of softswitch-based heterogeneous clustered media server, this paper proposed a limited resource vector load-balancing algorithm. The purpose of the algorithm was to balance the load of clu... Based on the system feature of softswitch-based heterogeneous clustered media server, this paper proposed a limited resource vector load-balancing algorithm. The purpose of the algorithm was to balance the load of clusters by utilizing all system resources effectively and to avoid violent shaking of the system per- formance. A lot of simulations on the Petri net model of load balance system are conducted and the algorithm is compared with some traditional algorithms on balancing ability for heterogeneity, system throughput, re- quest response time and performance stability. The results of simulations show that the algorithm achieves system higher performance and it has excellent ability to deal with the heterogeneity of clustered media server. 展开更多
关键词 load-balancing algorithm Heterogeneous cluster Media server SOFTSWITCH SPN (Stochastic Petri Net)
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基于SQL数据库和KD-Tree算法的船体型线匹配方法 被引量:1
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作者 余恺 马宁 +1 位作者 史琪琪 孙利 《舰船科学技术》 北大核心 2025年第11期8-14,共7页
为提高船舶初步设计效率,提出一种基于SQL数据库和KD-Tree算法的船舶型线快速匹配方法。针对船舶数据繁多复杂的问题,利用SQL语言保存、分类和提取船舶设计过程中的型线数据和特征线数据,提高了数据的存储和利用效率。针对船体复杂曲面... 为提高船舶初步设计效率,提出一种基于SQL数据库和KD-Tree算法的船舶型线快速匹配方法。针对船舶数据繁多复杂的问题,利用SQL语言保存、分类和提取船舶设计过程中的型线数据和特征线数据,提高了数据的存储和利用效率。针对船体复杂曲面的匹配问题,采取基于特征线描述船体特征,并求解特征线B样条控制点的方法保存船体的曲面特征数据。针对高维度变量的匹配问题,在不同大小的测试集中采用KD-Tree结构保存数据并采用最邻近搜索算法,能将船体型线的搜索匹配速度提高34.31%~84.16%。该方法对提高船舶初步设计效率提供有益的借鉴和帮助。 展开更多
关键词 船体设计 SQL数据库 KD-tree算法 船舶特征线
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Urban tree species classification based on multispectral airborne LiDAR 被引量:1
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作者 HU Pei-Lun CHEN Yu-Wei +3 位作者 Mohammad Imangholiloo Markus Holopainen WANG Yi-Cheng Juha Hyyppä 《红外与毫米波学报》 北大核心 2025年第2期211-216,共6页
Urban tree species provide various essential ecosystem services in cities,such as regulating urban temperatures,reducing noise,capturing carbon,and mitigating the urban heat island effect.The quality of these services... Urban tree species provide various essential ecosystem services in cities,such as regulating urban temperatures,reducing noise,capturing carbon,and mitigating the urban heat island effect.The quality of these services is influenced by species diversity,tree health,and the distribution and the composition of trees.Traditionally,data on urban trees has been collected through field surveys and manual interpretation of remote sensing images.In this study,we evaluated the effectiveness of multispectral airborne laser scanning(ALS)data in classifying 24 common urban roadside tree species in Espoo,Finland.Tree crown structure information,intensity features,and spectral data were used for classification.Eight different machine learning algorithms were tested,with the extra trees(ET)algorithm performing the best,achieving an overall accuracy of 71.7%using multispectral LiDAR data.This result highlights that integrating structural and spectral information within a single framework can improve the classification accuracy.Future research will focus on identifying the most important features for species classification and developing algorithms with greater efficiency and accuracy. 展开更多
关键词 multispectral airborne LiDAR machine learning tree species classification
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基于Extra Trees模型的咪唑类离子液体植物毒性预测及SHAP值分析
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作者 茹雨璇 曹雨希西 +2 位作者 胡肖肖 邵云海 马琳 《宝鸡文理学院学报(自然科学版)》 2025年第3期17-22,44,共7页
目的构建一种高效可行的机器学习模型用于咪唑类离子液体对植物的毒性预测,为绿色、低毒性离子液体的开发提供理论支持和新思路。方法收集200余个咪唑类离子液体对植物的毒性实验数据集,基于SMILES字符串提取分子描述符,构建了一个Extra... 目的构建一种高效可行的机器学习模型用于咪唑类离子液体对植物的毒性预测,为绿色、低毒性离子液体的开发提供理论支持和新思路。方法收集200余个咪唑类离子液体对植物的毒性实验数据集,基于SMILES字符串提取分子描述符,构建了一个Extra Trees预测模型。模型的性能通过决定系数(R^(2))、均方根误差(RMSE)等指标进行评估,并采用SHapley Additive exPlanations(SHAP)值分析预测结果,以量化特征值对毒性预测的贡献程度。结果Extra Trees模型在测试集上显示出良好的预测性能(R^(2)=0.944,RMSE=0.351)。SHAP分析揭示了分子中非极性基团、支链/环状结构、分子量等物理化学性质及分子结构对植物毒性的影响。结论构建的Extra Trees模型能够快速准确地预测咪唑离子液体的植物毒性,具有较好的泛化能力和鲁棒性,可为环境风险评估及绿色离子液体的设计开发提供科学依据。 展开更多
关键词 咪唑离子液体 机器学习 Extra trees模型 植物毒性
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Systematic Cloud-Based Optimization: Twin-Fold Moth Flame Algorithm for VM Deployment and Load-Balancing
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作者 Umer Nauman Yuhong Zhang +1 位作者 Zhihui Li Tong Zhen 《Intelligent Automation & Soft Computing》 2024年第3期477-510,共34页
Cloud computing has gained significant recognition due to its ability to provide a broad range of online services and applications.Nevertheless,existing commercial cloud computing models demonstrate an appropriate des... Cloud computing has gained significant recognition due to its ability to provide a broad range of online services and applications.Nevertheless,existing commercial cloud computing models demonstrate an appropriate design by concentrating computational assets,such as preservation and server infrastructure,in a limited number of large-scale worldwide data facilities.Optimizing the deployment of virtual machines(VMs)is crucial in this scenario to ensure system dependability,performance,and minimal latency.A significant barrier in the present scenario is the load distribution,particularly when striving for improved energy consumption in a hypothetical grid computing framework.This design employs load-balancing techniques to allocate different user workloads across several virtual machines.To address this challenge,we propose using the twin-fold moth flame technique,which serves as a very effective optimization technique.Developers intentionally designed the twin-fold moth flame method to consider various restrictions,including energy efficiency,lifespan analysis,and resource expenditures.It provides a thorough approach to evaluating total costs in the cloud computing environment.When assessing the efficacy of our suggested strategy,the study will analyze significant metrics such as energy efficiency,lifespan analysis,and resource expenditures.This investigation aims to enhance cloud computing techniques by developing a new optimization algorithm that considers multiple factors for effective virtual machine placement and load balancing.The proposed work demonstrates notable improvements of 12.15%,10.68%,8.70%,13.29%,18.46%,and 33.39%for 40 count data of nodes using the artificial bee colony-bat algorithm,ant colony optimization,crow search algorithm,krill herd,whale optimization genetic algorithm,and improved Lévy-based whale optimization algorithm,respectively. 展开更多
关键词 Optimizing cloud computing deployment of virtual machines load-balancing twin-fold moth flame algorithm grid computing computational resource distribution data virtualization
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Establishment of an efficient Agrobacterium rhizogenes-mediated hairy root transformation method for subtropical fruit trees 被引量:1
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作者 Mao Yin Yonghua Jiang +4 位作者 Yingjie Wen Fachao Shi Hua Huang Qian Yan Hailun Liu 《Horticultural Plant Journal》 2025年第4期1699-1702,共4页
Agrobacterium tumefaciens-mediated transformation has been widely adopted for plant genetic engineering and the study of gene function(Krenek et al.,2015).This method is prevalent in the genetic transformation of herb... Agrobacterium tumefaciens-mediated transformation has been widely adopted for plant genetic engineering and the study of gene function(Krenek et al.,2015).This method is prevalent in the genetic transformation of herbaceous plants,with notable applications in species such as Arabidopsis(Yin et al.,2024),soybean(Zhang et al.,2024),rice(Zhang et al.,2020),and Chinese cabbage(Li et al.,2021).However,its application in fruit trees is limited.This is primarily due to their long growth cycles and lack of rapid,efficient,and stable transgenic systems,which severely hinders foundational research involving plant genetic transformation(Mei et al.,2024).Furthermore,for subtropical fruit trees,the presence of recalcitrant seeds adds an extra layer of difficulty to genetic transformation(Umarani et al.,2015),as most methods rely on seed germination as a basis for transformation. 展开更多
关键词 study gene function krenek plant genetic engineering hairy root transformation fruit trees agrobacterium rhizogenes subtropical fruit trees genetic transformation chinese cabbage li
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Possibilities of native endophytic fungi as entomopathogenic biocontrol agents at a local scale:the case of deciduous and non-deciduous Mediterranean forest trees 被引量:1
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作者 Álvaro Benito-Delgado Sergio Diez-Hermano Julio Javier Diez 《Journal of Forestry Research》 2025年第3期224-236,共13页
Tree endophytic fungi play an important role in reducing insect herbivory,either by repelling them or kill-ing them directly.Identifying which fungi show such activ-ity could lead to new environmentally friendly pesti... Tree endophytic fungi play an important role in reducing insect herbivory,either by repelling them or kill-ing them directly.Identifying which fungi show such activ-ity could lead to new environmentally friendly pesticides.In this study,the Mediterranean basin climate conditions are projected to harshen in the next decades,will increase vulnerability of tree species to pest invasions.Endophytic fungi were isolated from wood and leaves of Quercus pyr-enaica,Q.ilex and Q.suber and tested for virulence against adults of the mealworm beetle,Tenebrio molitor L.using a direct contact method.Only 3 of 111 sporulating isolates had entomopathogenic activity,all identified as Lecanicillium lecanii.The pathogenicity of L.lecanii on T.molitor resulted in a median lethal time(TL50)of 14-16 d.Compared with commercial products,L.lecanii caused faster insect death than the nematode Steinernema carpocapsae and nuclear polyhedrosis virus(no effect on T.molitor survival),and slower than Beauveria bassiana(TL50=5),Beauveria pseu-dobassiana(TL50=8d)and Bacillus thuriengensis(80%mortality first day after inoculation).Mortality was also accelerated under water stress,reducing TL50 by an addi-tional 33%.Remarkably,water stress alone had a comparable effect on mortality to that of L.lecanii isolates.This study confirms T.molitor as a good model insect for pathogenicity testing and agrees with management policies proposed in the EU Green Deal. 展开更多
关键词 BIOCONTROL PESTICIDE tree pest Native fungi Climate change
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Rapid springtime leaf osmotic adjustment,but low late-seasonal and interannual variation in leaf turgor loss points in three temperate tree species 被引量:1
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作者 Norbert Kunert 《Journal of Forestry Research》 2025年第4期31-40,共10页
Leaf turgor loss point has been recognized as an important plant physiological trait explaining a species’drought tolerance( π_(tlp)).Less is known about the variation of π_(tlp) in time and how seasonal or interan... Leaf turgor loss point has been recognized as an important plant physiological trait explaining a species’drought tolerance( π_(tlp)).Less is known about the variation of π_(tlp) in time and how seasonal or interannual differences in water availability are affecting π_(tlp) as a static trait.I monitored the seasonal variation of π_(tlp) during a drought year starting in early spring with juvenile leaves and assessed the interannual variation in π_(tlp) of fully matured leaves among years with diverting water availability for three temperate broad-leaved tree species.The largest seasonal changes in π_(tlp) occurred during leaf unfolding until leaves were fully developed and matured.After leaves matured,no significant changes occurred for the rest of the vegetation period.Interannual variation that could be related to water availability was only present in one of the three tree species.The results suggest that the investigated species have a rapid period of osmotic adjustment early in the growing season followed by a period of relative stability,when π_(tlp) can be considered as a static trait. 展开更多
关键词 Drought Leaf drought tolerance traits tree mortality Turgor loss point
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基于i-Tree模型的北京10条绿道木本植物的生态效益评估 被引量:1
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作者 王希 徐敏 王美仙 《园林》 2025年第5期106-113,共8页
植物是发挥绿道生态功能的重要载体,量化植物的生态效益不仅能更直观地表现绿道的生态价值,而且可以为未来建设或更新绿道植物景观时选择高生态效益植物提供数据支撑,进而做出更加科学的决策。调查北京10条绿道木本植物的应用情况,运用i... 植物是发挥绿道生态功能的重要载体,量化植物的生态效益不仅能更直观地表现绿道的生态价值,而且可以为未来建设或更新绿道植物景观时选择高生态效益植物提供数据支撑,进而做出更加科学的决策。调查北京10条绿道木本植物的应用情况,运用i-Tree模型量化绿道以及单种本本植物在吸收CO_(2)、净化空气、截留雨水、节能4方面的生态效益,并探索绿道和植物特征与生态效益之间的关系。研究结果表明:北京10条绿道植物群落的稳定性较高,且种数分布比较均匀,生长状态稳定,有利于生态结构稳定性的维持以及生态效益的发挥;10条绿道共产生节能效益(672.82万元)>净化空气效益(135.73万元)>截留雨水效益(124.57万元)>吸收CO_(2)效益(16.68万元);乔木的单株生态效益高于灌木,高生态效益乔木有桑、胡桃、悬铃木、毛白杨、美国皂荚、刺槐、鹅掌楸、黑杨、臭椿、黑松;灌木有野茉莉、胡枝子、贴梗海棠、黄栌、平枝栒子、迎春、金银忍冬、欧洲荚蒾、暴马丁香、锦带花;株高高于6 m、胸径(地径)大于20 cm、冠幅大于4 m的木本植物生态效益较高;适当延长绿道长度、增加木本植物数量、丰富植物群落配置层次,可以提高绿道的生态效益。 展开更多
关键词 北京市绿道 木本植物 生态效益 i-tree模型 生态系统服务价值评估
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Intelligent sequential multi-impulse collision avoidance method for non-cooperative spacecraft based on an improved search tree algorithm 被引量:1
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作者 Xuyang CAO Xin NING +4 位作者 Zheng WANG Suyi LIU Fei CHENG Wenlong LI Xiaobin LIAN 《Chinese Journal of Aeronautics》 2025年第4期378-393,共16页
The problem of collision avoidance for non-cooperative targets has received significant attention from researchers in recent years.Non-cooperative targets exhibit uncertain states and unpredictable behaviors,making co... The problem of collision avoidance for non-cooperative targets has received significant attention from researchers in recent years.Non-cooperative targets exhibit uncertain states and unpredictable behaviors,making collision avoidance significantly more challenging than that for space debris.Much existing research focuses on the continuous thrust model,whereas the impulsive maneuver model is more appropriate for long-duration and long-distance avoidance missions.Additionally,it is important to minimize the impact on the original mission while avoiding noncooperative targets.On the other hand,the existing avoidance algorithms are computationally complex and time-consuming especially with the limited computing capability of the on-board computer,posing challenges for practical engineering applications.To conquer these difficulties,this paper makes the following key contributions:(A)a turn-based(sequential decision-making)limited-area impulsive collision avoidance model considering the time delay of precision orbit determination is established for the first time;(B)a novel Selection Probability Learning Adaptive Search-depth Search Tree(SPL-ASST)algorithm is proposed for non-cooperative target avoidance,which improves the decision-making efficiency by introducing an adaptive-search-depth mechanism and a neural network into the traditional Monte Carlo Tree Search(MCTS).Numerical simulations confirm the effectiveness and efficiency of the proposed method. 展开更多
关键词 Non-cooperative target Collision avoidance Limited motion area Impulsive maneuver model Search tree algorithm Neural networks
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Unveiling urbanization effects on trees outside forests along the urban-rural gradient in megacity Bengaluru
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作者 Tao Jiang Maximilian Freudenberg +3 位作者 Christoph Kleinn V.P.Tewari B.N.Diwakara Nils Nolke 《Forest Ecosystems》 2025年第1期56-65,共10页
Rapid urbanization has caused significant changes along the urban-rural gradient,leading to a variety of landscapes that are mainly shaped by human activities.This dynamic interplay also influences the distribution an... Rapid urbanization has caused significant changes along the urban-rural gradient,leading to a variety of landscapes that are mainly shaped by human activities.This dynamic interplay also influences the distribution and characteristics of trees outside forests(TOF).Understanding the pattern of these trees will support informed decision-making in urban planning,in conservation strategies,and altogether in sustainable land management practices in the urban context.In this study,we employed a deep learning-based object detection model and high resolution satellite imagery to identify 1.3 million trees with bounding boxes within a 250 km^(2)research transect spanning the urban-rural gradient of Bengaluru,a megacity in Southern India.Additionally,we developed an allometric equation to estimate diameter at breast height(DBH)from the tree crown diameter(CD)derived from the detected bounding boxes.Our study focused on analyzing variations in tree density and tree size along this gradient.The findings revealed distinct patterns:the urban domain displayed larger tree crown diameters(mean:8.87 m)and DBH(mean:43.78 cm)but having relatively low tree density(32 trees per hectare).Furthermore,with increasing distance from the city center,tree density increased,while the mean tree crown diameter and mean tree basal area decreased,showing clear differences of tree density and size between the urban and rural domains in Bengaluru.This study offers an efficient methodology that helps generating instructive insights into the dynamics of TOF along the urban-rural gradient.This may inform urban planning and management strategies for enhancing green infrastructure and biodiversity conservation in rapidly urbanizing cities like Bengaluru. 展开更多
关键词 Individual tree detection URBANIZATION tree density tree crown diameter
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Countability of Infinite Paths in the Infinity Tree: Proof of the Continuum Hypothesis in a Non-Cantorian Infinity Theory
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作者 Philip C. Jackson 《Advances in Pure Mathematics》 2025年第1期73-90,共18页
A previous paper showed that the real numbers between 0 and 1 could be represented by an infinite tree structure, called the ‘infinity tree’, which contains only a countably infinite number of nodes and arcs. This p... A previous paper showed that the real numbers between 0 and 1 could be represented by an infinite tree structure, called the ‘infinity tree’, which contains only a countably infinite number of nodes and arcs. This paper discusses how a finite-state Turing machine could, in a countably infinite number of state transitions, write all the infinite paths in the infinity tree to a countably infinite tape. Hence it is argued that the real numbers in the interval [0, 1] are countably infinite in a non-Cantorian theory of infinity based on Turing machines using countably infinite space and time. In this theory, Cantor’s Continuum Hypothesis can also be proved. And in this theory, it follows that the power set of the natural numbers P(ℕ) is countably infinite, which contradicts the claim of Cantor’s Theorem for the natural numbers. However, this paper does not claim there is an error in Cantor’s arguments that [0, 1] is uncountably infinite. Rather, this paper considers the situation as a paradox, resulting from different choices about how to represent and count the continuum of real numbers. 展开更多
关键词 INFINITY Countable UNCOUNTABLE Diagonalization Real Numbers Infinity tree Continuum Hypothesis Turing Machine Infinite Time Turing Machine Non-Cantorian
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Iceberg Draft Prediction Using Several Tree-Based Machine Learning Models
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作者 AZIMI Hamed SHIRI Hodjat 《Journal of Ocean University of China》 2025年第5期1269-1288,共20页
The Arctic region is experiencing accelerated sea ice melt and increased iceberg detachment from glaciers due to climate change.These drifting icebergs present a risk and engineering challenge for subsea installations... The Arctic region is experiencing accelerated sea ice melt and increased iceberg detachment from glaciers due to climate change.These drifting icebergs present a risk and engineering challenge for subsea installations traversing shallow waters,where ice-berg keels may reach the seabed,potentially damaging subsea structures.Consequently,costly and time-intensive iceberg manage-ment operations,such as towing and rerouting,are undertaken to safeguard subsea and offshore infrastructure.This study,therefore,explores the application of extra tree regression(ETR)as a robust solution for estimating iceberg draft,particularly in the preliminary phases of decision-making for iceberg management projects.Nine ETR models were developed using parameters influencing iceberg draft.Subsequent analyses identified the most effective models and significant input variables.Uncertainty analysis revealed that the superior ETR model tended to overestimate iceberg drafts;however,it achieved the highest precision,correlation,and simplicity in estimation.Comparison with decision tree regression,random forest regression,and empirical methods confirmed the superior perfor-mance of ETR in predicting iceberg drafts. 展开更多
关键词 sea-bottom founded structures iceberg draft extra tree regression decision tree regression random forest regression
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The Climate Change Influences on the Trees and a Life of Men in the Mekong River Delta-Remedial Actions
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作者 An Nguyen Thi Ngoc Trang Huynh Nguyen Thuy 《Journal of Environmental Science and Engineering(A)》 2025年第4期192-196,共5页
Mekong River Delta has many home-gardens,here,everybody organizes the tourisms.We observed the real situations and substances,evaluation,a choice at some households in the Mekong River Delta in order to have a purpose... Mekong River Delta has many home-gardens,here,everybody organizes the tourisms.We observed the real situations and substances,evaluation,a choice at some households in the Mekong River Delta in order to have a purpose of search,here,they have the home-gardens;the farmers plant fruit trees at the villages of provinces,that is a place which is influenced by the climate change.We went to the villages such as:Hiep Thanh village,Chau Thanh district,Long An province;Tan Phu village,Tan Phu Dong district,Tien Giang province;Tieu Can village,Tieu Can district,Tra Vinh province to observe the landscape(here 10 households for 1 village),and we took the sample to analyze.We knew the factors such as:drought,deficiency of water,salt water intrusion,flood.These factors influence the trees,assets,diseases,lives of the persons who stay here,and cause many damages.We compare many home-gardens having a climate change with the normal home-gardens.Thus,we propose the reasonable methods in order to fix the consequence and prevent the salt intrusion,flood,important damages…And we present some illustrations. 展开更多
关键词 Climate change trees MEN home-gardens
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Anatomical mapping of GFAP-immunoreactive astrocytes in the tree shrew brain
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作者 Ya-Tao Wang Qi-Qi Xu +10 位作者 Shuo-Wen Wang Jin-Kun Guo Shuai-Deng Wang Xin-Ya Qin Qing-Hong Shan Yu Wang Rong-Yu Liu Yue-Xiong Yang Chen-Wei Wang Peng Chen Jiang-Ning Zhou 《Zoological Research》 2025年第4期877-892,共16页
Astrocytes are associated with varying brain size between rodents and primates.As a close evolutionary relative of primates,the tree shrew(Tupaia belangeri)provides a valuable comparative model for investigating glial... Astrocytes are associated with varying brain size between rodents and primates.As a close evolutionary relative of primates,the tree shrew(Tupaia belangeri)provides a valuable comparative model for investigating glial architecture.However,the anatomical distribution and morphological characteristics of astrocytes in the tree shrew brain remain poorly characterized.In this study,glial fibrillary acidic protein(GFAP)immunofluorescence was employed to systematically examine the spatial distribution and morphology of astrocytes in the whole brain of tree shrews.Notably,GFAP-immunoreactive(ir)astrocytes were detected throughout the telencephalon,diencephalon,mesencephalon,metencephalon,and myelencephalon.Distinct laminar distribution was evident in regions such as the main olfactory bulb and hippocampus.Semi-quantitative comparisons revealed significant regional differences in astrocyte density between tree shrews and mice,encompassing the main olfactory bulb,accessory olfactory bulb,olfactory tubercle,cortex,hippocampus,cortical amygdaloid nucleus,hypothalamus,thalamus,superior colliculus,interpeduncular nucleus,median raphe nucleus,and parabrachial nucleus.Compared to mice,tree shrews exhibited higher astrocyte density with increased morphological complexity in the posterior hypothalamic nucleus,dorsomedial hypothalamic nucleus,ventromedial hypothalamic nucleus,and periaqueductal gray,but lower density with greater morphological complexity in the hippocampus and substantia nigra.In the paraventricular hypothalamic nucleus and lateral hypothalamic area,GFAP-ir astrocytes displayed comparable densities between tree shrews and mice but exhibited region-specific differences in morphological complexity.This study provides the first brain-wide mapping of GFAP-ir astrocytes in tree shrews,revealing marked interspecies differences in their distribution and morphology,and establishing a neuroanatomical framework for understanding astrocyte involvement in diverse physiological and behavioral functions. 展开更多
关键词 tree shrews ASTROCYTES Morphology HIPPOCAMPUS HYPOTHALAMUS
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The winter magic of trees: Dormancy
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作者 郝篆香 《疯狂英语(新悦读)》 2025年第3期44-46,77,共4页
1 Trees don't create their own heat like mammals do,and they don't have warm shelters or fur coats.So how do they survive the deep freeze of winter?In a way they do hibernate(冬眠)like bears—but in trees this... 1 Trees don't create their own heat like mammals do,and they don't have warm shelters or fur coats.So how do they survive the deep freeze of winter?In a way they do hibernate(冬眠)like bears—but in trees this is called dormancy and it's pretty amazing. 展开更多
关键词 DORMANCY trees winter survival
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