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Optimizing Spatial Pattern Analysis in Serial Remote Sensing Images through Empirical Mode Decomposition and Ant Colony Optimization
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作者 J Srinivasan S Uma +1 位作者 Saleem Raja Abdul Samad Jayabrabu Ramakrishnan 《Journal of Harbin Institute of Technology(New Series)》 CAS 2024年第4期52-60,共9页
Serial remote sensing images offer a valuable means of tracking the evolutionary changes and growth of a specific geographical area over time.Although the original images may provide limited insights,they harbor consi... Serial remote sensing images offer a valuable means of tracking the evolutionary changes and growth of a specific geographical area over time.Although the original images may provide limited insights,they harbor considerable potential for identifying clusters and patterns.The aggregation of these serial remote sensing images(SRSI)becomes increasingly viable as distinct patterns emerge in diverse scenarios,such as suburbanization,the expansion of native flora,and agricultural activities.In a novel approach,we propose an innovative method for extracting sequential patterns by combining Ant Colony Optimization(ACD)and Empirical Mode Decomposition(EMD).This integration of the newly developed EMD and ACO techniques proves remarkably effective in identifying the most significant characteristic features within serial remote sensing images,guided by specific criteria.Our findings highlight a substantial improvement in the efficiency of sequential pattern mining through the application of this unique hybrid method,seamlessly integrating EMD and ACO for feature selection.This study exposes the potential of our innovative methodology,particularly in the realms of urbanization,native vegetation expansion,and agricultural activities. 展开更多
关键词 spatial pattern analysis EMD ACO
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Spatial pattern analysis for quantification of landscape structure of Tadoba-Andhari Tiger Reserve,Central India 被引量:3
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作者 Ambica Paliwal Vinod Bihari 《Journal of Forestry Research》 SCIE CAS CSCD 2014年第1期185-192,共8页
Landscape structure is often regarded as an important factor that governs the distribution and abundance of species. Therefore it is critical to understand the landscapes and their dynamics. Patterns of landscape elem... Landscape structure is often regarded as an important factor that governs the distribution and abundance of species. Therefore it is critical to understand the landscapes and their dynamics. Patterns of landscape elements strongly influence the ecological characteristics. This study was designed to document and map the current status of the tropi-cal dry deciduous forest of the Tadoba-Andhari Tiger Reserve (TATR), Central India, (using IRS P6 LISS IV data) and to describe its landscape structure at three levels of organization viz. landscape, class, and patch. The study area was classified into 10 land cover classes that include 6 vegetation classes. The landscape structure was analyzed using FRAG-STATS using 12 set of indices. The TATR landscapes have a total of 2,307 patches with a mean patch size of 25.67 ha and patch density of 1.7 patches per km2. Amongst all land cover classes, mixed bamboo forest is dominant-it occupied maximum area (77.99%)-while riparian forest is least represented (0.32%). Mixed forest has maximum number of patches among all vegetation classes. Results have shown that despite being dominant in the area, mixed bamboo forest has low patch density (0.25/100 ha). Dominance of mixed bamboo forest is attributed to large patch sizes and not to the number of patches. This study has focussed on the approach of integrating satellite forest classification and forest inven-tory data for studying forest landscape patterns. 展开更多
关键词 Spatial pattern analysis landscape structure FRAGSTATS IRS P6 LISS IV.
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Population structure and spatial pattern analysis of Quercus aquifolioides on Sejila Mountain,Tibet,China 被引量:2
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作者 Zhiqiang Shen Jie Lu +4 位作者 Min Hua Xiaoqin Tang Xingle Qu Jingli Xue Jiangping Fang 《Journal of Forestry Research》 SCIE CAS CSCD 2018年第2期400-409,共10页
Understanding population structure provides basic ecological data related to species and ecosystems.Our objective was to understand the mechanisms involved in the maintenance of Quercus aquifolioides populations.Using... Understanding population structure provides basic ecological data related to species and ecosystems.Our objective was to understand the mechanisms involved in the maintenance of Quercus aquifolioides populations.Using a 1 ha permanent sample plot data for Q.aquifolioides on Sejila Mountain,Tibet Autonomous Region(Tibet),China,we analyzed the population structure of Q.aquifolioides by combining data for diameter class,static life table and survival curve.Simultaneously,the spatial distribution of Q.aquifolioides was studied using Ripley’s L Function in point pattern analysis.The results showed:(1) Individuals in Q.aquifolioides populations were mainly aggregated in the youngest age classes,that accounted for94.3% of the individuals; the older age classes had much smaller populations.Although the youngest age classes(ClassesⅠ and Ⅱ) had fewer individuals than Class Ⅲ,the total number of individuals in classes Ⅰ and Ⅱ was also greater than in classes Ⅳ to Ⅸ.In terms of tree height,fewsaplings,more medium-sized saplings and few large-sized trees were found.The diameter class structure of Q.aquifolioides populations formed an atypical ‘pyramid’type; the population was expanding,but growth was limited,tending toward a stable population.(2) Mortality of Q.aquifolioides increased continuously with age; life expectancy decreased over time,and the survivorship curve was close to a Deevey I curve.(3) The spatial distribution pattern of Q.aquifolioides varied widely across different developmental stages.Saplings and medium-sized tree showed aggregated distributions at the scales of 0–33 m and 0–29 m,respectively.The aggregation intensities of saplings and medium-sized trees at small scales were significantly stronger than that of large-sized trees.However,large-sized trees showed a random distribution at most scales.(4) No correlation was observed among saplings,medium-and large-sized trees at small scales,while a significant and negative association was observed as the scale increased.Strong competition was found among saplings,medium-and large-sized trees,while no significant association was observed between medium-and largesized trees at all scales.Biotic interactions and local ecological characteristics influenced the spatial distribution pattern of Q.aquifolioides populations most strongly. 展开更多
关键词 Point pattern analysis Population structure Quercus aquifolioides Sejila Mountain Spatial distribution pattern
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Pattern Analysis on DC Breakdown Phenomenon of Polyethylene Films 被引量:2
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作者 杜伯学 刘勇 刘弘景 《Transactions of Tianjin University》 EI CAS 2006年第5期325-329,共5页
Pattern analysis method was used to study DC breakdown characteristics of low-density polyethylene (LDPE) film and high-density polyethylene (HDPE) film, with particular attention paid to the breakdown phenomenon ... Pattern analysis method was used to study DC breakdown characteristics of low-density polyethylene (LDPE) film and high-density polyethylene (HDPE) film, with particular attention paid to the breakdown phenomenon identification. The breakdown pattern (BP) was recorded by a monocular-video-zoom microscope. The records showed that the effective area of BP was almost identical to the types of electrodes. The effective area od. The diameter was obtained by a mathematical was calculated by a mathematical integral methstatistic method. The study revealed that the DC breakdown voltage of LDPE was lower than that of HDPE. The diameter and effective area of LDPE were smaller than those of HDPE, but it is opposite for the condition of the needle-plane electrode with plane electrode grounded. As for the needle-plane electrode, the diameter and effective area with the films near the needle electrode were smaller than those near the plane electrode, and those in the middle of air gap were between them. As for the sphere-plane electrode, the diameter and effective area with the films near the plane electrode were smaller than those near the sphere electrode, and those in the middle of air gap were between them. 展开更多
关键词 POLYETHYLENE thin films insulation breakdown pattern analysis
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Pattern analysis of a linear dune field on the northern margin of Qarhan Salt Lake,northwestern China 被引量:6
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作者 LI Jiyan DONG Zhibao +4 位作者 QIAN Guangqiang ZHANG Zhengcai LUO Wanyin LU Junfeng WANG Meng 《Journal of Arid Land》 SCIE CSCD 2016年第5期670-680,共11页
In terms of formation mechanisms of linear dunes,there are open arguments for their widespread distribution and multi-morphological diversities.In order to clarify the formation mechanism of linear dunes of Qarhan Sal... In terms of formation mechanisms of linear dunes,there are open arguments for their widespread distribution and multi-morphological diversities.In order to clarify the formation mechanism of linear dunes of Qarhan Salt Lake,we used pattern analysis method to analyze the statistical characteristics and spatial variation of their pattern parameters.Except at the west-northwest margin,the pattern parameters showed regular spatial variation from the up-middle part towards the downwind end of the dune field.Based on the cumulative probability plots for inter-crest spacing and crest length,we divided the linear dunes into three groups,which corresponding to the three evolution stages of these dunes.The first group comprises erosional relics,with shorter crests,smaller inter-crest spacing and more random dune orientation.The second group comprises dunes whose sand supply is just sufficient to maintain stability and these dunes are approaching the net erosion stage.The crest length and inter-crest spacing of these dunes are much larger than those of the first group,and dune orientation is closer to the resultant drift direction (RDD) .The last group comprises linear dunes that are still undergoing vertical accretion and longitudinal elongation,which follows the RDD of the modern wind regime.The presence of regular spatial variation of pattern parameters and a similar geometry with the vegetated linear dunes suggest that deposition and erosion coexist in the development and evolution of linear dunes of Qarhan Salt Lake,i.e.deposition predominates at the downwind end of linear dunes in the vertical accretion and longitudinal elongation stage,whereas erosion mainly occurs at the upwind end of linear dunes in the degradation stage.Therefore,the formation mechanism of linear dunes in Qarhan Salt Lake can be reasonably explained by the combination of depositional and erosional theories. 展开更多
关键词 pattern analysis self-organization linear dunes dune field Qarhan Salt Lake Qaidam Basin
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Spatial pattern analysis and associations of different growth stages of populations of Abies georgei var.smithii in Southeast Tibet,China 被引量:3
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作者 SHEN Zhi-qiang LU Jie +1 位作者 HUA Min FANG Jiang-ping 《Journal of Mountain Science》 SCIE CSCD 2016年第12期2170-2181,共12页
Abies georgei var.smithii is an important plant species in Southeast Tibet,China.It has high ecological value in terms of biodiversity protection,as well as soil and water conservation.We analyzed the spatial pattern ... Abies georgei var.smithii is an important plant species in Southeast Tibet,China.It has high ecological value in terms of biodiversity protection,as well as soil and water conservation.We analyzed the spatial pattern and associations of A.georgei var.smithii populations at different growth stages by using Ripley's L function for point pattern analysis.The diameter structure was a nearly reverse 'J' shape.The amount of saplings and medium-sized trees accounts for a large part of the entire population,suggesting a high regeneration rate and an expanding population.In the transition from saplings to medium trees or to large trees,saplings show a significant aggregation distribution at small scales,while medium trees and large trees show a random distribution.There are significant inverse associations between saplings and medium trees and large trees at small scales,while there are no obvious associations between medium trees and large trees.The natural regeneration was affected by interspecific competition,and it was also affected by intraspecific competition.The joint effects of biological characteristics and environmental factors contribute to the spatial distribution pattern and associations of this A.georgei var.sm ithii population. 展开更多
关键词 Southeastern Tibet Abies georgei var.smithii Point pattern analysis Distribution pattern Spatial association
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Predicate Oriented Pattern Analysis for Biomedical Knowledge Discovery 被引量:2
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作者 Feichen Shen Hongfang Liu +2 位作者 Sunghwan Sohn David W. Larson Yugyung Lee 《Intelligent Information Management》 2016年第3期66-85,共20页
In the current biomedical data movement, numerous efforts have been made to convert and normalize a large number of traditional structured and unstructured data (e.g., EHRs, reports) to semi-structured data (e.g., RDF... In the current biomedical data movement, numerous efforts have been made to convert and normalize a large number of traditional structured and unstructured data (e.g., EHRs, reports) to semi-structured data (e.g., RDF, OWL). With the increasing number of semi-structured data coming into the biomedical community, data integration and knowledge discovery from heterogeneous domains become important research problem. In the application level, detection of related concepts among medical ontologies is an important goal of life science research. It is more crucial to figure out how different concepts are related within a single ontology or across multiple ontologies by analysing predicates in different knowledge bases. However, the world today is one of information explosion, and it is extremely difficult for biomedical researchers to find existing or potential predicates to perform linking among cross domain concepts without any support from schema pattern analysis. Therefore, there is a need for a mechanism to do predicate oriented pattern analysis to partition heterogeneous ontologies into closer small topics and do query generation to discover cross domain knowledge from each topic. In this paper, we present such a model that predicates oriented pattern analysis based on their close relationship and generates a similarity matrix. Based on this similarity matrix, we apply an innovated unsupervised learning algorithm to partition large data sets into smaller and closer topics and generate meaningful queries to fully discover knowledge over a set of interlinked data sources. We have implemented a prototype system named BmQGen and evaluate the proposed model with colorectal surgical cohort from the Mayo Clinic. 展开更多
关键词 Biomedical Knowledge Discovery pattern analysis PREDICATE Query Generation
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A township-level assessment of forest fragmentation using morphological spatial pattern analysis in Qujing,Yunnan Province,China
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作者 HUANG Xiao-yuan YE Yuan-hui +4 位作者 ZHANG Zhuo-ya YE Jiang-xia GAO Jie Marc BOGONOVICH ZHANG Xing 《Journal of Mountain Science》 SCIE CSCD 2021年第12期3125-3137,共13页
Forest fragmentation is an integral part of global change.Understanding forest fragmentation patterns and dynamics are of great significance for maintaining ecosystem stability.There are great differences in the inter... Forest fragmentation is an integral part of global change.Understanding forest fragmentation patterns and dynamics are of great significance for maintaining ecosystem stability.There are great differences in the interference of natural and human factors on forests in different towns of mountainous cities,and the characteristics of forest fragmentation are also obviously different.Forest fragmentation has been broadly studied,yet,it remains poorly understood at the township-scale within mountainous cities.In this study,the spatial form of forest landscape and forest fragmentation modes of towns were examined in Qujing City,Yunnan Province,China for the years of 2006 and 2016,relying heavily on the morphological spatial pattern analysis(MSPA)and K-means clustering algorithm.Results in 2016 showed that the forest landscape morphology of Qujing could be divided into seven classes:core,perforation,islet,bridge,edge,branch and ring;with landscape areas of 41.94%,1.22%,7.04%,11.12%,23.26%,11.74%and 3.68%respectively.Compared with 2006,the changes of landscape area were 1.71%,0.02%,0.30%,1.65%,0.20%,0.19%and 0.05%respectively.The townships in Qujing varied significantly in their landscape fragmentation patterns,and these patterns were spatially dependent.Different forest landscape forms have positive spatial correlations and differences.The forest fragmentation modes of towns can be divided into four types:Low anthropogenic towns,high anthropogenic towns,complex terrain towns and gentle terrain towns.Different ways of human activities play a decisive role in forest landscape fragmentation.The expansion of construction land and agricultural land intensifies forest fragmentation;however,man-made orderly and planned ecological restoration will greatly improve the forest coverage and improve the spatial form of urban forest landscape. 展开更多
关键词 Forest fragmentation Morphological spatial pattern analysis Morphological type China
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Machine Learning and Pattern Analysis Identify Distinctive Influences from Long-term Weekly Net Ecosystem Exchange at Four Deciduous Woodland Locations
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作者 David A.Wood 《Research in Ecology》 2022年第4期13-38,共26页
A methodology integrating correlation,regression(MLR),machine learning(ML),and pattern analysis of long-term weekly net ecosystem exchange(NEE)datasets are applied to four deciduous broadleaf forest(DBF)sites forming ... A methodology integrating correlation,regression(MLR),machine learning(ML),and pattern analysis of long-term weekly net ecosystem exchange(NEE)datasets are applied to four deciduous broadleaf forest(DBF)sites forming part of the AmeriFlux(FLUXNET2015)database.Such analysis effectively characterizes and distinguishes those DBF sites for which long-term NEE patterns can be accurately predicted using the recorded environmental variables,from those sites cannot be so delineated.Comparisons of twelve NEE prediction models(5 MLR;7 ML),using multi-fold cross-validation analysis,reveal that support vector regression generates the most accurate and reliable predictions for each site considered,based on fits involving between 16 and 24 available environmental variables.SVR can accurately predict NEE for datasets for DBF sites US-MMS and US-MOz,but fail to reliably do so for sites CA-Cbo and MX-Tes.For the latter two sites the predicted versus recorded NEE weekly data follow a Y≠X pattern and are characterized by rapid fluctuations between low and high NEE values across leaf-on seasonal periods.Variable influences on NEE,determined by their importance to MLR and ML model solutions,identify distinctive sets of the most and least influential variables for each site studied.Such information is valuable for monitoring and modelling the likely impacts of changing climate on the ability of these sites to serve as long-term carbon sinks.The periodically oscillating NEE weekly patterns distinguished for sites CA-Cbo and MX-Tes are not readily explained in terms of the currently recorded environmental variables.More detailed analysis of the biological processes at work in the forest understory and soil at these sites are recommended to determine additional suitable variables to measure that might better explain such fluctuations. 展开更多
关键词 EDDY-COVARIANCE CO_(2)-flux influences Multi-fold cross validation Weekly NEE pattern analysis Site specific NEE influences FLUXNET2015 protocols
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EI NIO PHENOMENON AND EXTENDED ASSOCIATE PATTERN ANALYSIS 被引量:7
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作者 CUIMao-chang MOJun QIAOFang-li 《Journal of Hydrodynamics》 SCIE EI CSCD 2004年第1期90-100,共11页
To study the causes of El Nino Phenomenon the Extended Associate PatternAnalysis (EAPA) is set up with monthly sea surface wind stress and precipitation besides Sea LevelPressure (SLP) and Sea Surface Temperature (SST... To study the causes of El Nino Phenomenon the Extended Associate PatternAnalysis (EAPA) is set up with monthly sea surface wind stress and precipitation besides Sea LevelPressure (SLP) and Sea Surface Temperature (SST) in or over the Pacific and related seas since 1979in present paper. The results show that El Nino Phenomenon means a SST redistribution, coveringalmost the whole Pacific that needs a huge amount of energy provided by air-sea interaction in themost Pacific regions; It is the wester burst and wind convergence, coming from meddle latitudesdirectly, instead of Kelvin waves that produce the strong SST warm signal in Nino regions; Twonegative SLP anomalies in middle of the North and South Pacific, most likely produced by the averageair pressure decreasing effect of explosive cyclones through precipitation, and the positive SLPanomaly o-ver the Asia-Australia land bridge, coming mainly from the south hemisphere with a littleinfluence from the Asian continent, are the three major causes for El Nino onset, they work togetherto produce anomalous wind convergence in Nino regions and wester burst in middle of the North andSouth Pacific that result in a warm tongue and cold pincers gearing together; Basically, during itsearly stage the ocean is forced by the atmosphere, while during its late stage the atmosphere isforced by the ocean. 展开更多
关键词 extended associate pattern analysis (EAPA) El nino phenomenon
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Spatial Structure and Development of Tourism Resources based on Point Pattern Analysis: A Case Study in Hainan Island, China 被引量:2
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作者 ZHANG Tongyan WANG Yingjie +2 位作者 WANG Yingying ZHANG Shengrui YU Hu 《Journal of Resources and Ecology》 CSCD 2022年第6期1058-1073,共16页
Tourism resources are the basic materials of tourism development, and they also provide the support for regional tourism spatial competition. The development of tourism depends on the degree to which tourism resources... Tourism resources are the basic materials of tourism development, and they also provide the support for regional tourism spatial competition. The development of tourism depends on the degree to which tourism resources are utilized, and it is of great guiding significance for their development and utilization to study their spatial structure. Based on a large sample of data on tourism resources, and starting from the characteristics of multi-type,multi-level and multi-combination, this paper puts forward a framework and method for analyzing the spatial structure of tourism resources. Taking Hainan Island as an example, this paper describes the spatial structure of tourism resources in Hainan Island by using the method of point pattern analysis, identifies the tourism resource development zones, and puts forward some suggestions for the development of tourism resources. The results are as follows:(1) The characteristic scale of the spatial structure of tourism resources in Hainan Island is 30.5 km, and there are significant differences in the distributions of all kinds of tourism resources.(2) Through the spatial structure map of tourism resources, the tourism resource development zones are identified, including three tourist central city levels, “one horizontal and three vertical” tourist belts and four tourist combination areas.(3) By combing the distribution of tourism resources and the development zones in Hainan Island, the cross-border characteristics of the tourism resources and development zones are obvious. In order to give full play to the spatial combination and superposition effect of tourism resources, a change from a single isolated development mode to the overall combined development between regions is suggested. On the provincial scale, it is relatively accurate to describe the spatial structure of tourism resources for point data with a large sample size. However, the method of point pattern analysis can not only accurately describe the spatial structure of tourism resources, but it can also provide reference for other types of regional spatial analyses. The research results provide a scientific basis for the spatial planning of regional tourism resources and have practical significance for the development of regional tourism. 展开更多
关键词 tourism resources spatial structure development area point pattern analysis method Hainan Island China
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Point pattern analysis of different age-classes of Larix principis-rupprechtii in Luya Mountain Reserve,Shanxi Province,China 被引量:1
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作者 ZHANG Jintun MENG Dongping 《Frontiers in Biology》 CSCD 2007年第1期69-74,共6页
Larix principis-rupprechtii forest is an important vegetation formation and has a large distribution area in Luya Mountain Reserve,China.Spatial pattern analysis on individual trees in different age-classes of Larix p... Larix principis-rupprechtii forest is an important vegetation formation and has a large distribution area in Luya Mountain Reserve,China.Spatial pattern analysis on individual trees in different age-classes of Larix principis-rupprechtii was made in this paper.Here,we employed the technique of point pattern analysis,which could analyze pat-terns under all scales along a gradient.It was based on spatial mapped points of individual distribution.The results of this study showed that the densities of the five age-classes varied in the order:age-class 3>age-class 4>age-class 5>age-class 2>age-class 1.Although age-classes 1 and 2 have much fewer individuals than other three age-classes do,the popula-tion was stable at present.However,it would be necessary to take some measures for improving population regeneration for a long-time view.The individuals of all age-classes focused on clumping distribution in space;however,their distribution pattern varied with the change of scale.This mainly depended on biological features of Larix principis-rupprechtii and forest environments,but it also meant that the scale was an important factor in controlling spatial distribution pattern of tree individuals.The feature of clumping distribution became more significant with the increase of age.The relationships between individuals in different age-classes were almost all significantly correlated with each other.These associations became more significant within the older age-classes.This suggested that the individuals of different age-classes were interdistributed,by which the population could get benefits in resource utilization.The technique of point pattern analysis is effective and easy to be used in species pattern study.Its results are more closer to the reality,especially for community structure. 展开更多
关键词 population pattern Larix principis-rupprechtii forest point pattern analysis age-class historical factors
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Pairwise Classifier Ensemble with Adaptive Sub-Classifiers for fMRI Pattern Analysis
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作者 Eunwoo Kim HyunWook Park 《Neuroscience Bulletin》 SCIE CAS CSCD 2017年第1期41-52,共12页
The multi-voxel pattern analysis technique is applied to fMRI data for classification of high-level brain functions using pattern information distributed over multiple voxels. In this paper, we propose a classifier en... The multi-voxel pattern analysis technique is applied to fMRI data for classification of high-level brain functions using pattern information distributed over multiple voxels. In this paper, we propose a classifier ensemble for multiclass classification in fMRI analysis, exploiting the fact that specific neighboring voxels can contain spatial pattern information. The proposed method converts the multiclass classification to a pairwise classifier ensemble, and each pairwise classifier consists of multiple sub-clas- sifiers using an adaptive feature set for each class-pair. Simulated and real fMRI data were used to verify the proposed method. Intra- and inter-subject analyses were performed to compare the proposed method with several well-known classitiers, including single and ensemble classifiers. The comparison results showed that the proposed method can be generally applied to multiclass classification in both simulations and real fMRI analyses. 展开更多
关键词 Ensemble learning Functional MRI Multi-voxel pattern analysis Pairwise classifier
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Regeneration pattern analysis of Quercus liaotungensis in a temperate forest using two-dimensional wavelet analysis
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作者 Xiangcheng MI Jihua HOU 《Frontiers in Biology》 CSCD 2009年第4期491-502,共12页
This paper introduces the two-dimensional(2D)wavelet analysis as a general interrogative technique for the detection of spatial structure in lattice data.The 2D wavelet analysis detects components of hierarchical stru... This paper introduces the two-dimensional(2D)wavelet analysis as a general interrogative technique for the detection of spatial structure in lattice data.The 2D wavelet analysis detects components of hierarchical structure and displays the locational information of the components.Patches and gaps of different spatial scales in graphical presentation of wavelet coefficients can be linked to the local ecological processes that determine patterns at stand or landscape scales.Derived from the 2D wavelet transform function,the calculation of wavelet variance can reduce the four-dimensional data of wavelet coefficients to a two-dimensional wavelet variance function and quantify the contribution of the given scale to the overall pattern.We illustrate the use of the 2D wavelet analysis by analyzing two simulated patterns and identifying the regeneration pattern of the Quercus liaotungensis in a warm temperate forest in north China.Our results indicate that the recruitment of Q.liaotungensis occurs in an overlapping area between the patch of adult and canopy gap at scales of 45m×45m–70m×70m and 20m×20m–30m×30m.The regeneration pattern of Q.liaotungensis can be mainly ascribed to a trade-off between two ecological processes:recruitment around parent trees and the physiological light requirements of seedlings and saplings.Our results provide a general portrayal of the regeneration pattern for the dispersal-limited and shade-intolerant Quercus species.We find that the two-dimensional wavelet analysis efficiently characterizes the scale-specific pattern of Q.liaotungensis at different life-history stages. 展开更多
关键词 Halo wavelet pattern analysis Quercus liaotungensis REGENERATION scale two-dimensional Mex-ican Hat wavelet two-dimensional wavelet analysis wavelet variance
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Two-dimensional pattern analysis on dominant species and community in subalpine meadow of Luya Mountain,Shanxi Province,China
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作者 ZHANG Jintun 《Frontiers in Biology》 CSCD 2007年第2期205-209,共5页
The spatial pattern analysis of population and community is important to understand community structure and has become one key topic in modern plant ecology.There are many techniques for analyzing one-dimensional patt... The spatial pattern analysis of population and community is important to understand community structure and has become one key topic in modern plant ecology.There are many techniques for analyzing one-dimensional pattern in ecological literature.Two-dimensional pattern analysis is better than one-dimensional analysis in the study on commu-nity spatial characteristics and structure.However,it is hard to analyze these two-dimensional patterns due to poor effective methodology.The two-dimensional sampling using two transects that meet at right angles was applied to get quadrat data in this work.And then the data from the two transects were analyzed separately by one-dimensional pattern analysis method,two-term local quadrat variance.The length,width,and area of patches at different scales of pattern for populations were obtained from the analysis.For community pattern,detrended correspondence analysis(DCA)was employed to summarize the species information firstly,and then the first DCA axis scores were analyzed to check its pattern.The application of this method to the pattern analysis on dominant populations and community for subalpine meadow(Comm.Polygonum viviparum+Carex rigescens+Kobresia bellardii)in the Luya mountains showed that it could release the characteristics of spatial pattern clearly and was a very effective technique.The method is easy to use and saves time with obvious advantages,compared with the two-dimensional pattern analysis methods presented in the litera-tures.In the study meadow,the patterns of the main dominant species,Polygonum viviparum,Carex rigescens,and Kobresia bellardii,were apparent and comparatively regular in shape with large areas of patches at the same scale compared with other species such as Festuca sp.and Thalictrum petaloideum.There were two or three scales of patterns for each plant population studied.This was related to population features,the interaction with environmental factors,and their dominant position in the community.The two scales of patterns for the meadow community were clear.The pattern of community was closely correlated with that of the main dominant species.The patches of dominant species were inter-distributed and overlapped,and formed the community pattern together.This is beneficial for utilization of resources,and keeping the community stable. 展开更多
关键词 population distribution spatial pattern community structure quantitative methodology two-dimensional pattern analysis
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Big-data-accelerated aperiodic Si/Ge superlattice prediction for quenching thermal conduction via pattern analysis
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作者 Yida Liu Run Hu +3 位作者 Yan Wang Jinglong Ma Zhangcan Yang Xiaobing Luo 《Energy and AI》 2021年第1期83-90,共8页
Thermal conductivity of material is one of the basic physical properties and plays an important role in manipu-lating thermal energy.In order to accelerate the prediction of material structure with desired thermal pro... Thermal conductivity of material is one of the basic physical properties and plays an important role in manipu-lating thermal energy.In order to accelerate the prediction of material structure with desired thermal property,machine learning algorithm has been widely adopted.However,in the optimization of multivariable material structure such as different lengths or proportions,the machine learning algorithm may be required to be recon-ducted again and again for each variable,which will consume a lot of computing resources.Recently,it has been found that the thermal conductivity of aperiodic superlattices is closely related to the degree of the structural ran-domness,which can also be reflected in their local pattern structures.Inspired by these,we propose a new pattern analysis method,in which machine learning only needs to be carried out for one time,and through which the optimal structure of different variables with low thermal conductivity can be obtained.To verify the method,we compare the thermal conductivities of the structure obtained by pattern analysis,conventional machine learning,and previous literature,respectively.The pattern analysis method is validated to greatly reduce the prediction time of multivariable structure with high enough accuracy and may promote further development of material informatics. 展开更多
关键词 Aperiodic superlattice pattern analysis Thermal conductivity Machine learning Atomic Green’s function
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Experimental Analyses of Flow Pattern and Heat Transfer in a Horizontally Oriented Polymer Pulsating Heat Pipe withMerged Liquid Slugs
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作者 Zhengyuan Pei Yasushi Koito 《Frontiers in Heat and Mass Transfer》 EI 2024年第5期1381-1397,共17页
Extended experiments were conducted on the oscillation characteristics of merged liquid slugs in a horizontally oriented polymer pulsating heat pipe(PHP).The PHP’s serpentine channel comprised 14 parallel channels wi... Extended experiments were conducted on the oscillation characteristics of merged liquid slugs in a horizontally oriented polymer pulsating heat pipe(PHP).The PHP’s serpentine channel comprised 14 parallel channels with a width of 1.3 mm and a height of 1.1 mm.The evaporator and condenser sections were 25 and 50 mm long,respectively,and the adiabatic section in between was 75mmlong.Using a plastic 3D printer and semi-transparent filament made from acrylonitrile butadiene styrene,the serpentine channel was printed directly onto a thin polycarbonate sheet to form the PHP.The PHP was charged with hydrofluoroether-7100.In the experiments,the evaporator section was heated,and the condenser section was cooled using high-temperature and low-temperature thermostatic baths,respectively.Flow patterns of the working fluid were obtained with temperature distributions of the PHP.A mathematical model was developed to analyze the flow patterns.Themerged liquid slugs were observed in every two channels,and their oscillation characteristics were found to be approximately the same in time and space.It was also found that the oscillations of the merged liquid slugs became slower,but the heat transfer rate of the PHP increased with a decrease in the filling ratio of the working fluid.This is because vapor condensation was enhanced in vapor plugs as the filling ratio decreased.However,the filling ratio had a lower limit,and the heat transfer rate was maximum when the filling ratio was 40.6%in the present experimental range. 展开更多
关键词 Pulsating heat pipe polymer heat pipe visualization experiment flow pattern analysis heat transfer enhancement
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Analysis of Landscape Patterns in the Urban-Rural Integrated Area Based on Moving Window: A Case Study of Sanshui District in Foshan City 被引量:1
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作者 CAO Xiaoshu LIU Yongwei LI Tao 《Journal of Landscape Research》 2018年第2期24-30,41,共8页
The urban-rural integrated area in Sanshui District of Foshan City was selected for research, and the impact of landscape pattern around the No.269 provincial highway was analyzed based on the land-use data in 2014 us... The urban-rural integrated area in Sanshui District of Foshan City was selected for research, and the impact of landscape pattern around the No.269 provincial highway was analyzed based on the land-use data in 2014 using the spatial analysis in GIS and the moving window method. The results showed that:(1) within the scope of a 2 km-range buffer zone, with a low degree of heterogeneity, land for construction use and water area were the dominant land-use types, while with a high degree of fragmentation, cultivated land, wooded land, grassland, garden land, land for other farm uses, and land unused were scattered;(2) the 250-m square moving window could well detect the change characteristics of landscape pattern on both sides of the road;(3) the gradient analysis of landscape pattern in urban-rural integrated area, which was conducted with the aid of a 750-m transect on both sides of the road, indicated that there were significant differences between landscape indexes both in the urban-rural integrated area and on both sides of the road;(4) the road that had an obvious cutting and fragmentation impact on the landscape was an important factor leading to the increasing fragmentation and heterogeneity to regional landscapes. 展开更多
关键词 Urban-rural integration Urban-rural gradient analysis Landscape pattern Moving window
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An Analysis Pattern for Equipment Management
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作者 WANG Zhou-jing, HU Hui-rong (Department of Automation, Xiamen University, Xiamen 361005, China) 《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 2002年第S1期282-283,共2页
In this paper, we account for this subject: how to de sign a pattern, it can track the state of the equipment of some organizations su ch as enterprise, organ, laboratory, school etc. We present an analysis pattern, w... In this paper, we account for this subject: how to de sign a pattern, it can track the state of the equipment of some organizations su ch as enterprise, organ, laboratory, school etc. We present an analysis pattern, which describes the whole procedure of managing the equipment and record the us ing of the equipment. It not only can track the quantity and location of the equ ipment of the whole organization, the more important is it can update the state of the equipment at real-time automatically. First,we design the static diagram(i.e. using UML class diagram to describe the basic state of the equipment). Then we consider its dynamic aspect, i.e., how th e state of the equipment to get changed according to the time. We use UML sequen ce diagram and state diagram to respectively describe the procedure of after pur chasing, transferring and discarding as useless of the equipment. Obviously, the manager can update the quantity and location of the equipment automatic ally. We character this pattern from the following five aspects: Problem: How the enterprise, organ, laboratory and school to track the quantity and location of the equipment. Circumstance: In some organizations, especially, in the manufactory or laborator y, when the number of the quantity and type is large or the distribution of the equipment is dispersed, they want to be able to track the quantity and location of the equipment. Forces: First, it is possible to the equipment be transferred or be discarded, n o matter when and where, the organization must be able to track the factual quan tity and location.Second, the solution must describe a basic semantic unit, that is, the solution must simple enough to apply it to various of circumstance, whi ch is the base of reusing. Third, the solution must include the interpret of the factual document. Solution: This part, we start with the basic demands, first using UML class diag ram to describe the basic pattern, which is an atomic pattern. Then using UML se quence diagram and state diagram to respectively describe the procedure of after purchasing, transferring and discarding as useless of the equipment and the rel evant change of the equipment in quantity and location. Consequence: Describing the effect of the pattern and how it supports the object . The pattern falls in the class which we call it semantic analysis patterns (SA P), it is a general model, which is abstract from the practical application. The case in fact is the minimum application which we can apply it to a certain fiel d, furthermore, we can implement the more particular demands or the similar appl ication by extending. 展开更多
关键词 analysis pattern SAP UML class diagram sequen ce diagram state diagram
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Comprehensive Analysis of Caching Performance under Probabilistic Traffic Patterns for Content Centric Networking
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作者 Dabin Kim Young-Bae Ko Sung-Hwa Lim 《China Communications》 SCIE CSCD 2016年第3期127-136,共10页
The phenomenon of data explosion represents a severe challenge for the upcoming big data era.However,the current Internet architecture is insufficient for dealing with a huge amount of traffic owing to an increase in ... The phenomenon of data explosion represents a severe challenge for the upcoming big data era.However,the current Internet architecture is insufficient for dealing with a huge amount of traffic owing to an increase in redundant content transmission and the end-point-based communication model.Information-centric networking(ICN)is a paradigm for the future Internet that can be utilized to resolve the data explosion problem.In this paper,we focus on content-centric networking(CCN),one of the key candidate ICN architectures.CCN has been studied in various network environments with the aim of relieving network and server burden,especially in name-based forwarding and in-network caching functionalities.This paper studies the effect of several caching strategies in the CCN domain from the perspective of network and server overhead.Thus,we comprehensively analyze the in-network caching performance of CCN under several popular cache replication methods(i.e.,cache placement).We evaluate the performance with respect to wellknown Internet traffic patterns that follow certain probabilistic distributions,such as the Zipf/Mandelbrot–Zipf distributions,and flashcrowds.For the experiments,we developed an OPNET-based CCN simulator with a realistic Internet-like topology. 展开更多
关键词 content-centric networking probabilistic Internet traffic patterns caching performance analysis OPNET
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