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A Hybrid Approach to Neighbour Discovery in Wireless Sensor Networks
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作者 Sagar Mekala K.Shahu Chatrapati 《Intelligent Automation & Soft Computing》 SCIE 2023年第1期581-593,共13页
In the contemporary era of unprecedented innovations such as Internet of Things(IoT),modern applications cannot be imagined without the presence of Wireless Sensor Network(WSN).Nodes in WSN use neighbour discovery(ND)... In the contemporary era of unprecedented innovations such as Internet of Things(IoT),modern applications cannot be imagined without the presence of Wireless Sensor Network(WSN).Nodes in WSN use neighbour discovery(ND)protocols to have necessary communication among the nodes.Neighbour discovery process is crucial as it is to be done with energy efficiency and minimize discovery latency and maximize percentage of neighbours discovered.The current ND approaches that are indirect in nature are categorized into methods of removal of active slots from wake-up schedules and intelligent addition of new slots.The two methods are found to have certain drawbacks.Thefirst category disturbs original integrity of wake-up schedules leading to reduced chances of discovering new nodes in WSN as neighbours.When second category is followed,it may have inefficient slots in the wake-up schedules leading to performance degradation.Therefore,the motivation behind the work in this paper is that by combining the two categories,it is possible to reap benefits of both and get rid of the limitations of the both.Making a hybrid is achieved by introducing virtual nodes that help maximize performance by ensuring original integrity of wake-up schedules and adding of efficient active slots.Thus a Hybrid Approach to Neighbour Discovery(HAND)protocol is realized in WSN.The simulation study revealed that HAND outperforms the existing indirect ND models. 展开更多
关键词 Wireless sensor networks neighbour discovery hybrid method energy efficiency wake-up schedules
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Entanglement and quantum phase transition in alternating XY spin chain with next-nearest neighbouring interactions 被引量:1
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作者 单传家 程维文 +2 位作者 刘堂昆 黄燕霞 李宏 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第11期4002-4008,共7页
By using the method of density-matrix renormalization-group to solve the different spin spin correlation functions, the nearest-neighbouring entanglement (NNE) and the next-nearest-neighbouring entanglement (NNNE)... By using the method of density-matrix renormalization-group to solve the different spin spin correlation functions, the nearest-neighbouring entanglement (NNE) and the next-nearest-neighbouring entanglement (NNNE) of one-dimensional alternating Heisenberg XY spin chain are investigated in the presence of alternating the-nearestneighbouring interaction of exchange couplings, external magnetic fields and the next-nearest neighbouring interaction. For a dimerised ferromagnetic spin chain, the NNNE appears only above a critical dimerized interaction, meanwhile, the dimerized interaction a effects a quantum phase transition point and improves the NNNE to a large extent. We also study the effect of ferromagnetic or antiferromagnetic next-nearest neighbouring (NNN) interaction on the dynamics of NNE and NNNE. The ferromagnetic NNN interaction increases and shrinks the NNE below and above a critical frustrated interaction respectively, while the antiferromagnetic NNN interaction always reduces the NNE. The antiferromagnetic NNN interaction results in a large value of NNNE compared with the case where the NNN interaction is ferromagnetic. 展开更多
关键词 the entanglement alternating XY spin chain the next-nearest neighbouring interactions
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The Background of Regional Lead Isotopic Compositions and Its Application in the Lower and Middle Reaches of the Yangtze River and Neighbouring Areas 被引量:1
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作者 Ma Zhendong and Shan Guangxiang Geochemistry Institute, China University of Geosciences, Wuhan, Hubei 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 1997年第2期158-170,共13页
The paper systematically deals with the background of regional isotopic compo-sitions in the lower and middle reaches of the Yangtze River and neighbouring areas. It isshown that the lead isotopic compositions of diff... The paper systematically deals with the background of regional isotopic compo-sitions in the lower and middle reaches of the Yangtze River and neighbouring areas. It isshown that the lead isotopic compositions of different geological formations and units are con-trolled by the primary mantle heterogeneity, dynamic process of crust-mantle interchange,abundances of uraninm, thorium and lead of various layers of the earth and timing. Studies onthe background of regional isotopic compositions may offer significant information forgeochemical regionalization, tracing of sources of ore-forming materials, and regionalprognosis of ore deposits. 展开更多
关键词 background of regional lead isotopic compositions tracing action lower and middle reaches of the Yangtze River and neighbouring areas
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Effects of local neighbourhood diversity on crown structure and productivity of individual trees in mature mixed-species forests 被引量:1
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作者 Louis Georgi Matthias Kunz +4 位作者 Andreas Fichtner Karl Friedrich Reich Anne Bienert Hans-Gerd Maas Goddert von Oheimb 《Forest Ecosystems》 SCIE CSCD 2021年第2期345-356,共12页
Background:Species-specific genotypic features,local neighbourhood interactions and resource supply strongly influence the tree stature and growth rate.In mixed-species forests,diversity-mediated biomass allocation ha... Background:Species-specific genotypic features,local neighbourhood interactions and resource supply strongly influence the tree stature and growth rate.In mixed-species forests,diversity-mediated biomass allocation has been suggested to be a fundamental mechanism underlying the positive biodiversity-productivity relationships.Empirical evidence,however,is rare about the impact of local neighbourhood diversity on tree characteristics analysed at a very high level of detail.To address this issue we analysed these effects on the individual-tree crown architecture and tree productivity in a mature mixed forest in northern Germany.Methods:Our analysis considers multiple target tree species across a local neighbourhood species richness gradient ranging from 1 to 4.We applied terrestrial laser scanning to quantify a large number of individual mature trees(N=920)at very high accuracy.We evaluated two different neighbour inclusion approaches by analysing both a fixed radius selection procedure and a selection based on overlapping crowns.Results and conclusions:We show that local neighbourhood species diversity significantly increases crown dimension and wood volume of target trees.Moreover,we found a size-dependency of diversity effects on tree productivity(basal area and wood volume increment)with positive effects for large-sized trees(diameter at breast height(DBH)>40 cm)and negative effects for small-sized(DBH<40 cm)trees.In our analysis,the neighbour inclusion approach has a significant impact on the outcome.For scientific studies and the validation of growth models we recommend a neighbour selection by overlapping crowns,because this seems to be the relevant scale at which local neighbourhood interactions occur.Because local neighbourhood diversity promotes individual-tree productivity in mature European mixed-species forests,we conclude that a small-scale species mixture should be considered in management plans. 展开更多
关键词 BIODIVERSITY Tree growth Crown architecture Quantitative structure models Terrestrial laser scanning neighbour classification
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A research on the geothermal structure in Yanqing-Huailai Basin and its neighbouring region
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作者 祖金华 吴乾蕃 廉雨方 《Acta Seismologica Sinica(English Edition)》 CSCD 1997年第4期115-118,共4页
AresearchonthegeothermalstructureinYanqing┐HuailaiBasinanditsneighbouringregionJIN-HUAZU(祖金华)QIAN-FANWU(吴乾蕃)... AresearchonthegeothermalstructureinYanqing┐HuailaiBasinanditsneighbouringregionJIN-HUAZU(祖金华)QIAN-FANWU(吴乾蕃)YU-FANGLIAN(廉雨方)... 展开更多
关键词 terrestrial heat flow two dimensional temperature structure Yanqing Huailai Basin and its neighbouring regions
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A natural neighbour method based on Fraeijs de Veubeke variational principle for materially non-linear problems
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作者 Xiang Li Serge Cescotto Barbara Rossi 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2009年第1期83-93,共11页
The natural neighbour method can be considered as one of many variants of the meshless methods. In the present paper, a new approach based on the Fraeijs de Veubeke (FdV) functional, which is initially developed for... The natural neighbour method can be considered as one of many variants of the meshless methods. In the present paper, a new approach based on the Fraeijs de Veubeke (FdV) functional, which is initially developed for linear elasticity, is extended to the case of geometrically linear but materially non-linear solids. The new approach provides an original treatment to two classical problems: the numerical evaluation of the integrals over the domain A and the enforcement of boundary conditions of the type ui = hi on Su. In the absence of body forces (Fi = 0), it will be shown that the calculation of integrals of the type fA .dA can be avoided and that boundary conditions of the type ui = hi on Su can be imposed in the average sense in general and exactly if hi is linear between two contour nodes, which is obviously the case for tTi = O. 展开更多
关键词 Natural neighbour method Meshless methodFraeijs de Veubeke variational principle DISCRETIZATION Voronoi cell
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ID-TIMS U-Pb Geochronology of the Tayatea Dyke Swarm of Australia: Identifying Tasmania's Nearest Neighbours in the Proterozoic
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作者 Charmaine MCGREGOR Steven DENYSZYN +3 位作者 Galen HALVERSON John EVERARD Grace CUMMING Clive CALVER 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2016年第S1期38-,共1页
The Tayatea Dyke Swarm(also known as the Tayatea Dolerite)comprises well-exposed northeast-trending tholeiitic dykes that intrude the Rocky Cape Group(RCG)of northwest Tasmania,Australia.The dykes commonly
关键词 TIMS PB Identifying Tasmania’s Nearest neighbours in the Proterozoic ID-TIMS U-Pb Geochronology of the Tayatea Dyke Swarm of Australia
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Enhancement of next-nearest-neighbouring entanglement in quantum Ising spin chain
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作者 单传家 刘继兵 +3 位作者 程维文 刘堂昆 黄燕霞 李宏 《Chinese Physics B》 SCIE EI CAS CSCD 2009年第9期3687-3692,共6页
Using the method of the Jordan-Wigner transformation for solving different spin-spin correlation functions, we have investigated the generation of next-nearest-neighbouring entanglement in a one-dimensional quantum Is... Using the method of the Jordan-Wigner transformation for solving different spin-spin correlation functions, we have investigated the generation of next-nearest-neighbouring entanglement in a one-dimensional quantum Ising spin chain with the Gaussian distribution impurities of exchange couplings and external magnetic fields taken into account. The maximal value of entanglement between the next-nearest-neighbouring qubits in the transverse Ising model was analysed in detail by varying the effectively controlled parameters such as interchange coupling, magnetic field and the system impurity. For such systems, where both exchange couplings and external magnetic field disorder appear, we show that it is possible to achieve next-nearest-neighbouring entanglement better than the previously discussed pure Ising spin chain case. We also show that the Gaussian distribution impurity can induce next-nearest-neighbouring entanglement, which can be used as a means to characterize quantum phase transition. 展开更多
关键词 next-nearest-neighbouring entanglement lsing spin chain Jordan Wigner transformation
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neighbourly nightmares
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《海外英语》 2011年第6期10-10,共1页
关键词 neighbourly nightmares》 英语学习 学习方法 阅读
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UNESCO Chair in Copyright and Neighbouring Rights Set Up in China
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作者 Xiao Hai 《中国专利与商标》 2001年第4期95-95,共1页
The ceremony marking the establishment ofUNESCO chair in copyright and neighbouringrights was held in the Renmin University ofChina(PUC).Mr.Koichiro Matsuura,DirectorGeneral of the United Nations Educational,Scientifi... The ceremony marking the establishment ofUNESCO chair in copyright and neighbouringrights was held in the Renmin University ofChina(PUC).Mr.Koichiro Matsuura,DirectorGeneral of the United Nations Educational,Scientific and Cultural Organisation(UNESCO)attended the ceremony.At which,Mr. 展开更多
关键词 UNESCO Chair in Copyright and neighbouring Rights Set Up in China
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Good Neighbours
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作者 周莲芳 《中学英语园地(八年级)》 2005年第2期4-5,共2页
关键词 Good neighbours
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Neighbour effects on plant biomass and its allocation for forbs growing in heterogeneous soils
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作者 Yongjie Liu Chunyan Ma +8 位作者 Shiting Liu Mingrui Liu Hui Li Mingxia Wang Guoe Li Hans J.De Boeck Fujiang Hou Zhanhui Tang Zhenxin Li 《Journal of Plant Ecology》 SCIE CSCD 2024年第4期90-99,共10页
Focal plants are considerably affected by their neighbouring plants,especially when growing in heterogeneous soils.A previous study on grasses demonstrated that soil heterogeneity and species composition affected plan... Focal plants are considerably affected by their neighbouring plants,especially when growing in heterogeneous soils.A previous study on grasses demonstrated that soil heterogeneity and species composition affected plant biomass and above-and belowground allocation patterns.We now tested whether these findings were similar for forbs.Three forb species(i.e.Spartina anglica,Limonium bicolor and Suaeda glauca)were grown in pots with three levels of soil heterogeneity,created by alternatively filling resource-rich and resource-poor substrates using small,medium or large patch sizes.Species compositions were created by growing these forbs either in monocultures or in mixtures.Results showed that patch size×species composition significantly impacted shoot biomass,root biomass and total biomass of forbs at different scales.Specifically,at the pot scale,shoot biomass,root biomass and total biomass increased with increasing patch size.At the substrate scale,shoot biomass and total biomass were higher at the large patch size than at the medium patch size,both in resource-rich and resource-poor substrates.Finally,at the community scale,monocultures had more shoot biomass,root biomass and total biomass than those in the two-or three-species mixtures.These results differ from earlier findings on the responses of grasses,where shoot biomass and total biomass decreased with patch size,and more shoot biomass and total biomass were found in resource-rich than resource-poor substrates.To further elucidate the effects of soil heterogeneity on the interactions between neighbour plants,we advise to conduct longer-term experiments featuring a variety of functional groups. 展开更多
关键词 biomass allocation neighbour effect patch size soil heterogeneity shoot biomass
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POI数据挖掘在市场调查与分析大赛中的应用——以东北三省养猪企业数据挖掘为例
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作者 于淼 于海玲 宋贽 《养猪》 2024年第4期4-7,共4页
随着大数据技术的快速发展,海量数据的采集、挖掘和分析广泛应用于商业、农业、医疗等各个领域。本文基于POI数据挖掘构建市场调查方法,通过核密度和最邻近距离分析,利用POI数据分析东北三省养猪企业的分布特征,从而了解地区优势产业,... 随着大数据技术的快速发展,海量数据的采集、挖掘和分析广泛应用于商业、农业、医疗等各个领域。本文基于POI数据挖掘构建市场调查方法,通过核密度和最邻近距离分析,利用POI数据分析东北三省养猪企业的分布特征,从而了解地区优势产业,并结合人口分布、企业分布等数据进行校核与验证。研究结果表明,POI数据挖掘为市场调查与分析大赛提供了有效的数据收集和市场分析方法。 展开更多
关键词 POI数据挖掘 市场调查 养猪企业 核密度分析
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A Novel Insertion Solution for the Travelling Salesman Problem
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作者 Emmanuel Oluwatobi Asani Aderemi Elisha Okeyinka +5 位作者 Sunday Adeola Ajagbe Ayodele Ariyo Adebiyi Roseline Oluwaseun Ogundokun Temitope Samson Adekunle Pragasen Mudali Matthew Olusegun Adigun 《Computers, Materials & Continua》 SCIE EI 2024年第4期1581-1597,共17页
The studypresents theHalfMax InsertionHeuristic (HMIH) as a novel approach to solving theTravelling SalesmanProblem (TSP). The goal is to outperform existing techniques such as the Farthest Insertion Heuristic (FIH) a... The studypresents theHalfMax InsertionHeuristic (HMIH) as a novel approach to solving theTravelling SalesmanProblem (TSP). The goal is to outperform existing techniques such as the Farthest Insertion Heuristic (FIH) andNearest Neighbour Heuristic (NNH). The paper discusses the limitations of current construction tour heuristics,focusing particularly on the significant margin of error in FIH. It then proposes HMIH as an alternative thatminimizes the increase in tour distance and includes more nodes. HMIH improves tour quality by starting withan initial tour consisting of a ‘minimum’ polygon and iteratively adding nodes using our novel Half Max routine.The paper thoroughly examines and compares HMIH with FIH and NNH via rigorous testing on standard TSPbenchmarks. The results indicate that HMIH consistently delivers superior performance, particularly with respectto tour cost and computational efficiency. HMIH’s tours were sometimes 16% shorter than those generated by FIHand NNH, showcasing its potential and value as a novel benchmark for TSP solutions. The study used statisticalmethods, including Friedman’s Non-parametric Test, to validate the performance of HMIH over FIH and NNH.This guarantees that the identified advantages are statistically significant and consistent in various situations. Thiscomprehensive analysis emphasizes the reliability and efficiency of the heuristic, making a compelling case for itsuse in solving TSP issues. The research shows that, in general, HMIH fared better than FIH in all cases studied,except for a few instances (pr439, eil51, and eil101) where FIH either performed equally or slightly better thanHMIH. HMIH’s efficiency is shown by its improvements in error percentage (δ) and goodness values (g) comparedto FIH and NNH. In the att48 instance, HMIH had an error rate of 6.3%, whereas FIH had 14.6% and NNH had20.9%, indicating that HMIH was closer to the optimal solution. HMIH consistently showed superior performanceacross many benchmarks, with lower percentage error and higher goodness values, suggesting a closer match tothe optimal tour costs. This study substantially contributes to combinatorial optimization by enhancing currentinsertion algorithms and presenting a more efficient solution for the Travelling Salesman Problem. It also createsnew possibilities for progress in heuristic design and optimization methodologies. 展开更多
关键词 Nearest neighbour heuristic farthest insertion heuristic half max insertion heuristic tour construction travelling salesman problem
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蚂蚁筑巢对纳帕海面山土壤碳积累及分配的影响 被引量:1
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作者 刘攀 陆梅 +7 位作者 吕晶花 杨志东 赵定蓉 孙官发 闪昇阳 李聪 赵旭燕 陈志明 《北京林业大学学报》 CAS CSCD 北大核心 2024年第5期114-125,共12页
【目的】揭示纳帕海面山森林蚁巢与非蚁巢土壤总有机碳储量及活性有机碳组分的分配特征,为阐明蚂蚁活动对森林土壤有机碳沉积影响的过程及机制提供关键数据支撑。【方法】以纳帕海面山云杉−冷杉森林群落为研究对象,比较蚁巢和非蚁巢2种... 【目的】揭示纳帕海面山森林蚁巢与非蚁巢土壤总有机碳储量及活性有机碳组分的分配特征,为阐明蚂蚁活动对森林土壤有机碳沉积影响的过程及机制提供关键数据支撑。【方法】以纳帕海面山云杉−冷杉森林群落为研究对象,比较蚁巢和非蚁巢2种处理土壤总有机碳储量、活性碳组分(微生物生物量碳、易氧化有机碳、颗粒有机碳、可溶性有机碳)及其碳分配(微生物生物量碳/总有机碳、易氧化有机碳/总有机碳、颗粒有机碳/总有机碳、可溶性有机碳/总有机碳)的差异,并分析蚂蚁筑巢活动引起土壤理化环境改变对总有机碳储量及活性有机碳组分分配的影响。【结果】蚂蚁筑巢显著影响土壤有机碳积累及活性碳组分分配(P<0.05)。其中,蚁巢土壤有机碳储量是非蚁巢的5.7倍;蚁巢土壤总有机碳、微生物生物量碳、易氧化有机碳、颗粒有机碳含量分别提高了3.8、2.7、4.0、3.5倍;蚁巢土壤易氧化有机碳/总有机碳均值大小比蚁巢高出1.50%,而非蚁巢土壤微生物生物量碳/总有机碳、颗粒有机碳/总有机碳、可溶性有机碳/总有机碳均值分别比蚁巢高0.43%、3.30%、3.21%;不同处理和土层仅对土壤总有机碳、微生物生物量碳、颗粒有机碳和可溶性有机碳含量存在明显的交互作用(P<0.05);回归分析结果表明土壤微生物生物量碳、颗粒有机碳、可溶性有机碳和易氧化有机碳分别解释了96.45%、96.35%、95.13%、94.27%的总有机碳变化;主成分分析表明土壤密度、全氮和速效磷是总有机碳储量的主控因子,而速效氮、速效磷、土壤密度等是活性碳组分积累的主要驱动因子;全钾、含水量分别是颗粒性有机碳与可溶性有机碳分配的主要影响因子。【结论】蚂蚁筑巢主要通过改变土壤紧实度、氮磷养分条件等环境因子,进而调控纳帕海面山森林土壤总有机碳储量与活性有机碳组分的分配,研究结果有助于理解高原湿地面山土壤碳积累过程的土壤动物学调控机制。 展开更多
关键词 蚂蚁筑巢 土壤有机碳储量 土壤有机碳组分及分配 纳帕海面山森林
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利益衡量视域下人工智能生成内容的邻接权保护 被引量:1
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作者 费安玲 喻钊 《河北大学学报(哲学社会科学版)》 CSSCI 2024年第4期116-127,共12页
对人工智能生成内容保护与否、如何保护的争论,本质上是对既有利益如何协调的讨论。化解人工智能生成内容带来的利益冲突,需从人工智能运行的底层逻辑出发,以利益分析为主线,审视著作权法保护的条件。人工智能生成内容符合广义邻接权的... 对人工智能生成内容保护与否、如何保护的争论,本质上是对既有利益如何协调的讨论。化解人工智能生成内容带来的利益冲突,需从人工智能运行的底层逻辑出发,以利益分析为主线,审视著作权法保护的条件。人工智能生成内容符合广义邻接权的保护要求。但现有邻接权制度无法对人工智能生成内容提供保护,邻接权制度需进行一定的扩张,结合人工智能生成内容的特性和关联的利益,宜新设“生成式信息使用者权”,并对权利主体、具体保护条件、权利行使限制等方面进行明确。 展开更多
关键词 利益衡量 人工智能 邻接权 著作权
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蚂蚁筑巢对森林土壤氮库组分含量和分配的影响
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作者 闪昇阳 陆梅 +4 位作者 李聪 赵定蓉 孙官发 陈志明 冯峻 《西部林业科学》 CAS 北大核心 2024年第3期144-153,160,共11页
为阐明蚂蚁筑巢对纳帕海面山森林土壤氮循环的影响过程及机制,以该区云杉-冷杉森林群落为研究对象,比较蚁巢和非蚁巢2种野外实验处理土壤氮组分(全氮、碱解氮、硝态氮、铵态氮、微生物生物量氮)含量及其分配(碱解氮/全氮、硝态氮/全氮... 为阐明蚂蚁筑巢对纳帕海面山森林土壤氮循环的影响过程及机制,以该区云杉-冷杉森林群落为研究对象,比较蚁巢和非蚁巢2种野外实验处理土壤氮组分(全氮、碱解氮、硝态氮、铵态氮、微生物生物量氮)含量及其分配(碱解氮/全氮、硝态氮/全氮、铵态氮/全氮、微生物生物量氮/全氮)的差异特征,分析蚂蚁筑巢活动引起土壤理化环境变化对氮库组分积累与分配的影响。结果显示:(1)蚂蚁筑巢显著影响土壤氮组分含量积累及分配(P<0.05)。其中,蚁巢土壤的全氮、硝态氮、铵态氮、碱解氮和微生物生物量氮含量是非蚁巢的2.2、3.5、1.4、4.2、1.8倍;蚁巢土壤的氮组分(碱解氮、硝态氮、铵态氮、微生物生物量氮)占全氮比例是非蚁巢的1.88、1.47、1.38、1.58倍;土壤氮库组分及其分配受不同处理、土层及交互作用的影响显著(P<0.05)。(2)回归分析显示,土壤铵态氮和硝态氮分别解释全氮变化的87.29%、80.84%。(3)曼特尔分析表明,氮库组分积累的主要驱动因子是土壤孔隙度、全磷和pH,土壤氮库组成分配的主要驱动因子是有机质、速效钾和速效磷。可得结论:蚂蚁筑巢显著改变土壤孔隙度、酸碱性、碳磷钾养分等环境因子,进而调控纳帕海面山森林土壤氮库组分含量的积累与分配。研究结果有助于理解高原湿地面山土壤氮积累过程的土壤动物学调控机制。 展开更多
关键词 蚂蚁筑巢 氮组分 氮积累 氮分配 面山森林 纳帕海
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基于PCA+KNN和kernal-PCA+KNN算法的废旧纺织物鉴别
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作者 李宁宁 刘正东 +2 位作者 王海滨 韩熹 李文霞 《分析测试学报》 CAS CSCD 北大核心 2024年第7期1039-1045,共7页
该研究采集了15类废旧纺织物的4 998张近红外谱图,以7∶3的比例分为训练集和验证集,并分别采用主成分分析(PCA)与核主成分分析(kernal-PCA)两种不同降维方法对数据进行降维,并选用余弦相似度(cosine)核作为kernal-PCA的最佳核函数,最后... 该研究采集了15类废旧纺织物的4 998张近红外谱图,以7∶3的比例分为训练集和验证集,并分别采用主成分分析(PCA)与核主成分分析(kernal-PCA)两种不同降维方法对数据进行降维,并选用余弦相似度(cosine)核作为kernal-PCA的最佳核函数,最后分别将PCA和kernal-PCA降维处理后的数据进行k-近邻算法(KNN)训练。结果表明,kernal-PCA+KNN的模型准确率(95.17%)优于PCA+KNN模型的准确率(92.34%)。研究表明,kernal-PCA+KNN算法可以实现15类废旧纺织物识别准确率的提升,为废旧纺织物在线近红外自动分拣提供有力的技术支撑。 展开更多
关键词 废旧纺织物 主成分分析(PCA) 核主成分分析(kernel-PCA) k-近邻算法(KNN) 分类识别
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Cluster-Based Nearest-Neighbour Classifier and Its Application on the Lightning Classification 被引量:2
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作者 Loris Nanni Alessandra Lumini 《Journal of Computer Science & Technology》 SCIE EI CSCD 2008年第4期573-581,共9页
The problem addressed in this paper concerns the prototype generation for a cluster-based nearest-neighbour classifier. It considers, to classify a test pattern, the lines that link the patterns of the training set an... The problem addressed in this paper concerns the prototype generation for a cluster-based nearest-neighbour classifier. It considers, to classify a test pattern, the lines that link the patterns of the training set and a set of prototypes. An efficient method based on clustering is here used for finding subgroups of similar patterns with centroid being used as prototype. A learning method is used for iteratively adjusting both position and local-metric of the prototypes. Finally, we show that a simple adaptive distance measure improves the performance of our nearest-neighbour-based classifier. The performance improvement with respect to other nearest-neighbour-based classifiers is validated by testing our method on a lightning classification task using data acquired from the Fast On-orbit Recording of Transient Events (FORTE) satellite, moreover the performance improvement is validated through experiments with several benchmark datasets. The performance of the proposed methods are also validated using the Wilcoxon Signed-Rank test. 展开更多
关键词 nearest-neighbour classifier CLUSTERING adaptive distance
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一种面向工业应用的机器人回位方法
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作者 侯龙潇 《机械制造与自动化》 2024年第4期235-240,286,共7页
针对工业机器人作业过程中非正常停机引起位姿处于未知状态而导致机器人无法从停机位置自动返回初始位置的问题,提出一种工业机器人的回位方法。设计机器人回位路径,结合k-近邻算法、构造回位空间以及空间分类阈值对机器人的位姿信息进... 针对工业机器人作业过程中非正常停机引起位姿处于未知状态而导致机器人无法从停机位置自动返回初始位置的问题,提出一种工业机器人的回位方法。设计机器人回位路径,结合k-近邻算法、构造回位空间以及空间分类阈值对机器人的位姿信息进行分类化处理;重构机器人特征数据进行决策树模型的训练;使用训练完成的模型决策回位路径后执行机器人回位程序,实现工业机器人自动返回初始位。回位试验实验结果表明:在随机位姿和携带多样工具的状态下机器人回位成功率为93.3%。 展开更多
关键词 工业机器人 回位方法 空间构造 路径设计 决策树算法 K-近邻算法
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