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基于Delaunay三角网与核哈希表的空间co-location核模式挖掘
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作者 张琪 芦俊丽 +2 位作者 段鹏 罗浩瑜 唐明香 《云南民族大学学报(自然科学版)》 2026年第1期117-128,154,共13页
空间co-location模式挖掘用于揭示地理空间数据中实体间关联关系,广泛应用于城市规划和环境监测等领域.然而,传统方法在处理大规模或复杂空间数据时,通常依赖人为设定的距离阈值,存在计算效率与准确度局限.为此,提出了一种基于Delaunay... 空间co-location模式挖掘用于揭示地理空间数据中实体间关联关系,广泛应用于城市规划和环境监测等领域.然而,传统方法在处理大规模或复杂空间数据时,通常依赖人为设定的距离阈值,存在计算效率与准确度局限.为此,提出了一种基于Delaunay三角网和核哈希表的空间co-location核模式挖掘方法.该方法利用Delaunay三角剖分优化空间数据的邻近关系,避免人为设定阈值的问题,并构建Delaunay邻域物化模型(DNM)减少尖锐三角形,以提升空间数据的组织效率.同时,结合核哈希表实现高效存储和检索,提出HKP算法,提高核模式挖掘的计算效率.实验结果表明,与现有优秀算法CPM、DTC和Join-less相比,HKP算法在准确性和扩展性上均具有显著优势,适用于大规模空间数据挖掘应用. 展开更多
关键词 空间co-location核模式 DELAUNAY三角网 核哈希表 HKP DNM
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基于Context量化和空间co-location模式的熵编码在基因组压缩中的应用
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作者 陈慧 王丽珍 《中国科技信息》 2025年第13期135-137,共3页
1背景随着大数据和云计算等信息处理技术日趋应用广泛,熵编码日益普遍,它是以信息的概率分布特性作为编码的依据,是一种无失真的信源压缩和一种无损的压缩编码。然而在实际应用中,这些条件概率分布事先并不知道,需要通过估计得到。对条... 1背景随着大数据和云计算等信息处理技术日趋应用广泛,熵编码日益普遍,它是以信息的概率分布特性作为编码的依据,是一种无失真的信源压缩和一种无损的压缩编码。然而在实际应用中,这些条件概率分布事先并不知道,需要通过估计得到。对条件概率分布进行估计的过程称为Context建模。已有一些现成的基因组序列压缩工具可供使用,但这些工具并不针对特定基因组序列。因此,基于Context建模熵编码技术的生物基因组序列研究仍具有重要的理论意义。 展开更多
关键词 Context建模 空间co-location模式 熵编码 基因组压缩
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Seasonal emission patterns of airborne phytoncides in temperate forests from autumn to early spring:a case study of Xishui National Forest Park(Yichun,Northeast China)
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作者 Hongda Cai Yitong Wang +6 位作者 Xianwen Huang Sen Zhang Yankun Liu Jian Zhang Dongmei Zhao Peng Zhao Xiuhua Zhao 《Journal of Forestry Research》 2026年第1期256-271,共16页
Xishui National Forest Park in Heilongjiang Province hosts China's most pristine temperate forests and serves as a key site for ecotourism and forest therapy.However,the emission patterns of phytoncides(key bio ac... Xishui National Forest Park in Heilongjiang Province hosts China's most pristine temperate forests and serves as a key site for ecotourism and forest therapy.However,the emission patterns of phytoncides(key bio active compounds) remain poorly understood,limiting their therapeutic application.This study provides the first comprehensive characterization of spatiotemporal dynamics in airborne phytoncides and their synergistic interactions with environmental factors throughout the autumn-early spring seasonal transition in a temperate forest ecosystem.We analyzed the compositional dynamics of phytoncides and terpenoid content variations using thermal desorption-gas chromatography-mass spectrometry(TD-GC-MS) from September 2024 to March 2025.This period encompassed seasonal transitions from autumn to early spring,including diurnal variations in September and snowfall events in November.The method demonstrated detection limits(LODs) ranging from 1.35 to 5.33 ng m-3 and quantification limits(LOQs) from 4.09 to 16.15 ng m-3.Our results revealed pronounced seasonal fluctuations in phytoncide composition.In September,terpenoids,esters,alcohols,and alkanes displayed a diurnal "decrease-increase" trend,whereas aldehydes and ketones peaked at midday.Notably,esters and alcohols were undetectable in November and January.By January,terpenoids reached their lowest proportion(0.17±0.02%) at noon.Five terpenoids(α-pinene,myrcene,D-limonene,camphene,p-cymene) were detected in September,four(α-pinene,D-limonene,camphene,p-cymene) in November,two(D-limonene,p-cymene) in January,and only p-cymene in March.The total concentration and emission rate of the five terpenoids peaked in September afternoons at 1961.58±106.67 ng m^(-3) and653.86±35.56 ng m^(-3) h^(-1),respectively.Nocturnal emissions(32131.95±2522.21 ng m^(-3)) significantly surpassed daytime levels(14473.04±958.49 ng m^(-3)),with emission rates escalating from 1447.30±95.85 ng m^(-3) h^(-1)(day) to 5355.33±420.37 ng m^(-3) h^(-1)(night),marking a3.7-fold increase.Snowfall dramatically elevated terpenoid concentrations(pre-snowfall:158.58±14.12 ng m^(-3);post-snowfall:1080.57±57.76 ng m^(-3)) and emission rates(pre-snowfall:52.86±4.71 ng m^(-3) h^(-1);post-snowfall:360.19±19.25 ng m^(-3) h^(-1)),reflecting a 6.8-fold surge.This study underscores the profound influence of light intensity,seasonal shifts,and climatic conditions on airborne phytoncide levels,offering a scientific foundation for optimizing forest therapy and ecotourism strategies. 展开更多
关键词 Phytoncides Seasonal variation Diurnal-nocturnal patterns Snowfall impact Emission patterns
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Variation in vegetation characteristics and landscape patterns of urban forests:implications for ecosystem management under rapid urbanization
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作者 Jialin Zhong Jiamei Tu +5 位作者 Xin Li Yao Fu Wei Liu Foyi Zhang Shuyang Hu Qiong Wang 《Journal of Forestry Research》 2026年第2期224-238,共15页
Urban forests are essential components of green infrastructure,however,rapid urbanization-induced changes in landscape patterns may affect their ecosystem services through complex ecological processes.A total of 184 s... Urban forests are essential components of green infrastructure,however,rapid urbanization-induced changes in landscape patterns may affect their ecosystem services through complex ecological processes.A total of 184 sample plots in the built-up areas of Nanchang,China,were used as research sites.Urbanization intensities were categorized by the rate of impervious surface area,and forest types were classified into landscape and relaxation forest,attached forest(AF),road forest(RF),and ecological public welfare forest.This study aimed to explore the spatial variations in vegetation characteristics and landscape pattern indices of different forest types under rapid urbanization.The results indicated that the largest patch index(LPI),aggregation index(AI),and percentage of landscape(PLAND)in RF and AF were lower than those in the other forest types(p<0.05).With increasing urbanization intensity,the mean perimeter-area ratio increased by 130.84%,whereas the PLAND,LPI,and AI decreased by 22−86%(p<0.05).Redundancy analysis and variation partitioning suggested that the interpretation rate of landscape pattern indices for variations in vegetation characteristics increased from low to heavy urbanization areas.Especially,the landscape shape index,patch connection index,PLAND,and mean patch size were significantly correlated with vegetation characteristics(e.g.,tree richness,herb coverage,and tree height).In the future,appropriate landscape layout superiority cases should be considered in different urbanization areas and forest types;for instance,increasing the patch connection index will beneficially improve the diversity of trees and herbs in heavy urbanization areas and the RF.This study serves as a reference for maximizing the ecosystem services of urban forests. 展开更多
关键词 Forest type VEGETATION URBANIZATION Landscape pattern
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Improving Online Restore Performance of Backup Storage via Historical File Access Pattern
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作者 Ruidong Chen Guopeng Wang +5 位作者 Jingyuan Yang Ziyu Wang Fang Zou Jia Sun Xingpeng Tang Ting Chen 《Computers, Materials & Continua》 2026年第3期1536-1558,共23页
The performance of data restore is one of the key indicators of user experience for backup storage systems.Compared to the traditional offline restore process,online restore reduces downtime during backup restoration,... The performance of data restore is one of the key indicators of user experience for backup storage systems.Compared to the traditional offline restore process,online restore reduces downtime during backup restoration,allowing users to operate on already restored files while other files are still being restored.This approach improves availability during restoration tasks but suffers from a critical limitation:inconsistencies between the access sequence and the restore sequence.In many cases,the file a user needs to access at a given moment may not yet be restored,resulting in significant delays and poor user experience.To this end,we present Histore,which builds on the user’s historical access sequence to schedule the restore sequence,in order to reduce users’access delayed time.Histore includes three restore approaches:(i)the frequency-based approach,which restores files based on historical file access frequencies and prioritizes ensuring the availability of frequently accessed files;(ii)the graph-based approach,which preferentially restores the frequently accessed files as well as their correlated files based on historical access patterns,and(iii)the trie-based approach,which restores particular files based on both users’real-time and historical access patterns to deduce and restore the files to be accessed in the near future.We implement a prototype of Histore and evaluate its performance from multiple perspectives.Trace-driven experiments on two datasets show that Histore significantly reduces users’delay time by 4-700×with only 1.0%-14.5%additional performance overhead. 展开更多
关键词 Online restore access pattern correlation graph TRIE
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Vascular plant diversity and distribution pattern in Tajikistan:A global hotspot of diversity
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作者 ZHOU Yixin MA Suliya +7 位作者 LI Wenjun Parvina KURBONOVA Mariyo BOBOEV LI Yufan Hikmat HISORIEV MA Keping YANG Weikang ZHANG Yuanming 《Regional Sustainability》 2026年第1期37-53,共17页
Tajikistan represents a core region of the biodiversity hotspot in Central Asian mountains and has exceptional vascular plant diversity.However,the species diversity of the country faces urgent conservation challenges... Tajikistan represents a core region of the biodiversity hotspot in Central Asian mountains and has exceptional vascular plant diversity.However,the species diversity of the country faces urgent conservation challenges.There has been a lack of a comprehensive and multidimensional assessment to inform strategic conservation planning.Therefore,this study integrated 4 key biodiversity indices including species richness(SR),phylogenetic diversity(PD),threatened species richness(TSR),and endemic species richness(ESR)to map species diversity distribution patterns,identify conservation gaps,and elucidate their effects of climatic factors.This study revealed that species diversity shows a clear trend of decreasing from the western region to the eastern region of Tajikistan.The central–western mountains(specifically the Gissar-Darvasian and Zeravshanian regions)emerge as irreplaceable biodiversity hotspots.However,we found a severe spatial mismatch between these priority areas and the existing protected areas(PAs).Protection coverage for all hotspots was alarmingly low,ranging from 31.00%to 38.00%.Consequently,a critical 64.80%of integrated priority areas fall outside of the current PAs,representing a major conservation gap.This study identified precipitation seasonality and isothermality as the principal drivers,collectively explaining over 50.00%of the diversity variation and suggesting high vulnerability to hydrological shifts.Furthermore,we detected significant geographic sampling bias in the public biodiversity databases,with the most critical hotspot being systematically under-sampled.This study provides a robust scientific basis for conservation action,highlighting the urgent need to strategically expand PAs in the under-protected southwestern region and to mitigate critical sampling gaps through targeted data digitization and field surveys.These measures are indispensable for securing Tajikistan’s unique biodiversity and achieving the Kunming-Montreal Global Biodiversity Framework Target 3(“30×30 Protection”). 展开更多
关键词 Vascular plant Species diversity Distribution pattern Conservation gaps TAJIKISTAN
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Patterned line-illumination mesoscopy with a moving slit for enhancing background suppression in cortex-wide mouse brain imaging
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作者 Chaowei Zhuang Yi Yang Hao Xie 《Chinese Physics B》 2026年第2期679-684,共6页
Wide-field mesoscopy provides the capabilities of cortex-wide field of view(FOV),cellular resolution and high frame rate for neuronal imaging in the mouse brain.However,inherent background fluorescence degrades the im... Wide-field mesoscopy provides the capabilities of cortex-wide field of view(FOV),cellular resolution and high frame rate for neuronal imaging in the mouse brain.However,inherent background fluorescence degrades the image quality and hinders neuronal signal extraction.To address this problem,we first introduce a cortex-wide,high-resolution lineillumination mesoscope with a moving slit designed for in vivo mouse brain imaging.This system achieves a 6.6×6.6 mm FOV,microscale cellular resolution,a high frame rate of 10 Hz,as well as the background rejection ability.Furthermore,we integrated patterned illumination into the system to enhance the background suppression.Experimental results show that the proposed system successfully captures neurodynamics in the living mouse brain.Compared with conventional wide-field mesoscopes,the cortex-wide patterned line-illumination mesoscope(PLIM)achieves a threefold increase in the signal-to-background ratio(SBR).With patterned illumination integrated,the SBR enhancement further reaches four-anda-half-fold. 展开更多
关键词 wide-field fluorescence imaging optical sectioning patterned illumination
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Patterns of utilization of antipsychotic drugs and direct medical costs among patients with schizophrenia in a tertiary care hospital
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作者 Aqeel Haider Lekha Saha Debashish Basu 《World Journal of Psychiatry》 2026年第1期125-135,共11页
BACKGROUND Drug utilization research has an important role in assisting the healthcare administration to know,compute,and refine the prescription whose principal objective is to enable the rational use of drugs.Resear... BACKGROUND Drug utilization research has an important role in assisting the healthcare administration to know,compute,and refine the prescription whose principal objective is to enable the rational use of drugs.Research in developing nations relating to the cost of treatment is scarce when compared with developed countries.Thus,the drug utilization research studies from developing nations are most needed,and their number has been growing.AIM To evaluate patterns of utilization of antipsychotic drugs and direct medical cost analysis in patients newly diagnosed with schizophrenia.METHODS The present study was observational in type and based on a retrospective cohort to evaluate patterns of utilization of antipsychotic drugs using World Health Organization(WHO)core prescribing indicators and anatomical therapeutic chemical/defined daily dose indicators.We also calculated direct medical costs for a period of 6 months.RESULTS This study has found that atypical antipsychotics are the mainstay of treatment for schizophrenia in every age group and subcategories of schizophrenia.The evaluation based on WHO prescribing indicators showed a low average number of drugs per prescription and low prescribing frequency of antipsychotics from the National List of Essential Medicines 2015 and the WHO Essential Medicines List 2019.The total mean drug cost of our study was 1396 Indian rupees.The total mean cost due to the investigation in our study was 1017.34 Indian rupees.Therefore,the total mean direct medical cost incurred on patients in our study was 4337.28 Indian rupees.CONCLUSION The information from the present study can be used for reviewing and updating treatment policy at the institutional level. 展开更多
关键词 patterns of utilization Antipsychotic drugs Direct medical cost SCHIZOPHRENIA DRUGS
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Unravelling tree diversity patterns and responses to environmental gradients in a tropical forest landscape of the Western Ghats
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作者 Naveen Babu Kanda Ashaq Ahmad Dar +2 位作者 Kurian Ayushi Ayyappan Narayanan Narayanaswamy Parthasarathy 《Plant Diversity》 2026年第1期92-106,共15页
Understanding spatial patterns of plant species diversity and the factors(e.g.,climate and human)that drive these patterns is essential for biodiversity conservation.We used data from 1700.1-ha forest plots in the She... Understanding spatial patterns of plant species diversity and the factors(e.g.,climate and human)that drive these patterns is essential for biodiversity conservation.We used data from 1700.1-ha forest plots in the Shettihalli tropical forest landscape of the Western Ghats biodiversity hotspot,India,to analyse tree community composition and the drivers ofα-diversity(Shannon)andβ-diversity(LCBD).Compositional patterns were visualized using Non-Metric Multidimensional Scaling(NMDS),and hybrid feature selection with structural equation modeling(SEM)was employed to evaluate the direct and indirect effects of environmental variables on diversity.NMDS identified four distinct forest types in the Shettihalli landscape:semi-evergreen,dry deciduous,moist deciduous,and plantation forests,each with distinct plant composition.Shannon diversity and ecological uniqueness was significantly higher in semi-evergreen forest than in deciduous forest plots.The SEMs explained about 79%and 39–45%of the variation inα-diversity andβ-diversity.Our analysis indicated that current diversity patterns result from multiple processes,with structure,disturbance,and edaphic parameters exerting the strongest direct and indirect effects onα-diversity.β-diversity,in contrast,was largely influenced by climate,topography,stand structure,and edaphic factors.Overall,our findings indicate that various factors(e.g.,climate,topography,and human disturbance)interact to shape tree diversity patterns in tropical forests.These findings will help develop unique conservation and management strategies for distinct forest types in tropical forest ecosystems. 展开更多
关键词 Alpha diversity Beta diversity Machine learning Structural equation modeling Vegetation patterns Western Ghats
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模糊对象的空间Co-location模式挖掘研究 被引量:27
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作者 欧阳志平 王丽珍 陈红梅 《计算机学报》 EI CSCD 北大核心 2011年第10期1947-1955,共9页
空间co-location模式表示的是空间对象的实例在一个相同的区域内频繁地空间并置.过去人们已经对确定及不确定数据的co-location模式挖掘问题进行了一些研究,但是针对模糊对象上进行的研究还没有.模糊对象在许多领域里都有着非常重要的应... 空间co-location模式表示的是空间对象的实例在一个相同的区域内频繁地空间并置.过去人们已经对确定及不确定数据的co-location模式挖掘问题进行了一些研究,但是针对模糊对象上进行的研究还没有.模糊对象在许多领域里都有着非常重要的应用,比如生物医学图像数据库和GIS.该文研究模糊对象的空间co-location模式挖掘问题.首先,定义模糊对象上空间co-location模式挖掘的相关概念,包括模糊参与率、模糊参与度等.其次,提出FB算法挖掘模糊对象的co-location模式.接着,提出了3种改进算法,包括剪枝对象、减少实例间连接、改进剪枝步,以提高挖掘性能、加快co-location规则的产生.最后通过大量的实验说明FB算法及其改进算法的效果和效率. 展开更多
关键词 模糊对象 co-location模式 空间数据挖掘 模糊参与率 减少连接
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一种带稀有特征的空间co-location模式挖掘新方法 被引量:13
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作者 冯岭 王丽珍 高世健 《南京大学学报(自然科学版)》 CSCD 北大核心 2012年第1期99-107,共9页
Co-location模式挖掘是找出频繁出现在一起的一组空间特征的集合.在传统的方法中,一般假定每个空间特征在模式中具有平等的地位,然而,当模式中存在稀有特征时,有些模式便无法被获取.若使用现有针对含有稀有特征的挖掘方法,一些不频繁的... Co-location模式挖掘是找出频繁出现在一起的一组空间特征的集合.在传统的方法中,一般假定每个空间特征在模式中具有平等的地位,然而,当模式中存在稀有特征时,有些模式便无法被获取.若使用现有针对含有稀有特征的挖掘方法,一些不频繁的模式也会被挖掘出来.针对以上问题,本文提出了最小加权参与率的概念,在此新概念下,不但可以挖掘出带稀有特征的频繁co-location模式,而且可以排除不频繁的模式.此外,针对算法时间复杂度高的问题,根据加权参与率排序后的部分向下闭合性提出了一种有效的剪枝方法,大大地提高了算法的执行效率.实验表明我们的方法对带稀有特征的co-location模式挖掘问题是有效的. 展开更多
关键词 co-location模式 稀有特征 加权参与率
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含关键特征的显著Co-location模式挖掘研究 被引量:6
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作者 方圆 王丽珍 周丽华 《数据采集与处理》 CSCD 北大核心 2018年第4期692-703,共12页
空间Co-location模式是一组在空间中频繁并置的空间特征的子集。空间Co-location模式挖掘通常假设空间实例之间相互独立,然而,在实际应用中,不同空间特征、不同实例之间往往相互作用或依赖。空间Co-location关键特征是指对模式具有主导... 空间Co-location模式是一组在空间中频繁并置的空间特征的子集。空间Co-location模式挖掘通常假设空间实例之间相互独立,然而,在实际应用中,不同空间特征、不同实例之间往往相互作用或依赖。空间Co-location关键特征是指对模式具有主导作用的特征。在频繁模式中,识别含关键特征的Co-location模式并摘取模式中的关键特征,为用户提供更精简的挖掘结果,提高Co-location模式的可用性,对Co-location模式挖掘具有重要意义。本文首先定义了含有关键特征的显著频繁Co-location模式新概念,以及一系列度量指标以识别显著频繁Co-location模式中的关键特征;其次,给出了一个挖掘显著频繁Co-location模式和关键特征的算法;最后,在模拟和真实数据集上进行了大量的实验,验证了所提出算法的效果及性能。 展开更多
关键词 空间数据挖掘 空间并置(co-location)模式 关键特征 模式显著性
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基于凝聚层次聚类的co-location模式挖掘 被引量:4
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作者 高世健 王丽珍 +1 位作者 冯岭 陈红梅 《广西师范大学学报(自然科学版)》 CAS 北大核心 2011年第2期167-173,共7页
空间的co-location模式代表一组空间对象的子集,它们的实例在空间中频繁地关联,它是空间数据挖掘的重要研究方向。本文首先介绍co-location模式挖掘的基本算法,然后提出一种新的挖掘算法,算法先对空间数据进行凝聚层次聚类,在聚类结果... 空间的co-location模式代表一组空间对象的子集,它们的实例在空间中频繁地关联,它是空间数据挖掘的重要研究方向。本文首先介绍co-location模式挖掘的基本算法,然后提出一种新的挖掘算法,算法先对空间数据进行凝聚层次聚类,在聚类结果上挖掘co-location模式,最后对这种新的算法作实验评估。 展开更多
关键词 空间数据挖掘 co-location模式 凝聚层次聚类 参与度
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一种基于U-AHC的不确定空间co-location模式挖掘算法 被引量:7
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作者 高世健 王丽珍 肖清 《计算机研究与发展》 EI CSCD 北大核心 2011年第S3期60-66,共7页
不确定数据在一些重要应用领域中是固有存在的,如传感器网络和移动物体追踪等.如何快速、方便、有效地从不确定数据库中发现潜在的、有价值的和人们感兴趣的信息变得越来越重要.首先,把传统的凝聚层次聚类算法(AHC)扩展到不确定的凝聚... 不确定数据在一些重要应用领域中是固有存在的,如传感器网络和移动物体追踪等.如何快速、方便、有效地从不确定数据库中发现潜在的、有价值的和人们感兴趣的信息变得越来越重要.首先,把传统的凝聚层次聚类算法(AHC)扩展到不确定的凝聚层次聚类算法(U-AHC),然后在聚类结果的基础上计算候选co-location模式的粗表实例,并对参与度小于最小参与度阈值的候选模式进行剪枝.接着展开其粗表实例并动态地实施剪枝,最后生成频繁的co-location模式.实验证明这个算法是正确的,而且效率较高. 展开更多
关键词 空间数据挖掘 不确定数据 空间co-location模式 凝聚层次聚类算法 参与度
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基于加权欧氏距离的空间Co-location模式挖掘算法研究 被引量:4
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作者 周剑云 王丽珍 杨增芳 《计算机科学》 CSCD 北大核心 2014年第S1期425-428,共4页
空间Co_location模式挖掘关注空间对象实例在一定区域内同时出现的关系。目前大多数研究都是把空间对象的各个实例按同等权重对待,但现实中容易发现同一类对象的不同实例其大小规模、重要程度或是影响力覆盖范围都是不一样的。因此考虑... 空间Co_location模式挖掘关注空间对象实例在一定区域内同时出现的关系。目前大多数研究都是把空间对象的各个实例按同等权重对待,但现实中容易发现同一类对象的不同实例其大小规模、重要程度或是影响力覆盖范围都是不一样的。因此考虑空间对象实例的影响力因素,引入加权欧氏距离阈值参与计算,能发现更具实际价值的Co_location模式。 展开更多
关键词 空间数据挖掘 co-location模式挖掘 加权欧氏距离
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空间极大co-location模式挖掘研究 被引量:4
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作者 胡新 王丽珍 +1 位作者 周丽华 温佛生 《计算机科学与探索》 CSCD 2014年第2期150-160,共11页
空间co-location模式代表了一组空间特征的子集,它们的实例在空间中频繁地关联。挖掘空间co-location模式的研究已经有很多,但是针对极大co-location模式挖掘的研究非常少。提出了一种新颖的空间极大co-location模式挖掘算法。首先扫描... 空间co-location模式代表了一组空间特征的子集,它们的实例在空间中频繁地关联。挖掘空间co-location模式的研究已经有很多,但是针对极大co-location模式挖掘的研究非常少。提出了一种新颖的空间极大co-location模式挖掘算法。首先扫描数据集得到二阶频繁模式,然后将二阶频繁模式转换为图,再通过极大团算法求解得到空间特征极大团,最后使用二阶频繁模式的表实例验证极大团得到空间极大co-location频繁模式。实验表明,该算法能够很好地挖掘空间极大co-location频繁模式。 展开更多
关键词 空间数据挖掘 空间极大co-location模式挖掘 极大团
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不均匀模糊空间对象的分层次co-location模式挖掘方法 被引量:1
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作者 俞庆英 罗永龙 +1 位作者 吴倩 陈传明 《计算机应用》 CSCD 北大核心 2016年第11期3113-3117,3151,共6页
针对现有的co-location模式挖掘算法无法有效处理不均匀分布空间对象的问题,提出一种不均匀模糊空间对象的分层次co-location模式挖掘方法。首先提出一种不均匀数据集的生成方法;然后对不均匀分布的数据集进行层次划分,使每个区域具有... 针对现有的co-location模式挖掘算法无法有效处理不均匀分布空间对象的问题,提出一种不均匀模糊空间对象的分层次co-location模式挖掘方法。首先提出一种不均匀数据集的生成方法;然后对不均匀分布的数据集进行层次划分,使每个区域具有均匀的空间分布;再基于改进的PO_RI_PC算法对划分后的模糊对象进行空间数据挖掘。该方法基于距离变化系数构建每个子区域的邻域关系图,进而完成区域融合,实现co-location模式挖掘。实验结果表明,与传统方法相比,所提方法的执行效率更高,随实例个数和不均匀度的变化获得的co-location集个数更多,同比情况下平均提高约25%,获得了更精确的挖掘结果。 展开更多
关键词 模糊对象 co-location模式挖掘 隶属度 不均匀度 距离变化系数
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Mineral resources of Asia continent:Resource endowment,mining industry pattern,and contributions to the world economy
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作者 Xi-feng Chen Gang Wang +2 位作者 Yan-xiong Mei Hai-jie Zhao Yan-yun Ma 《China Geology》 2026年第1期1-24,共24页
Mineral resources in Asia continent and its mining industry play a significant role in the economic growth and industrialization of both Asia and the world.Asia continent boasts the most comprehensive kinds of mineral... Mineral resources in Asia continent and its mining industry play a significant role in the economic growth and industrialization of both Asia and the world.Asia continent boasts the most comprehensive kinds of minerals,with reserves of at least 38 of over 80 widely used minerals worldwide accounting for more than30%of the global total reserves.Asia continent experienced three main tectonic evolution and mineralization stages:The Precambrian,the Paleozoic,and the Mesozoic to Cenozoic.The abundant mineral resources in this continent can be divided into seven first-order metallogenic belts(metallogenic domains),18 second-order metallogenic belts(metallogenic provinces),61 third-order metallogenic belts(metallogenic zones),and nine main minerogenetic series.Asia continent exhibits the most significant metallogenic specialization among all continents.Specifically,granite belts of Asia continent manifest pronounced metallogenic specialization of tin,rare metals,and porphyry Cu-Au-Mo deposits.Its maficultramafic rock belts and ophiolite belts display notable metallogenic specialization of lateritic nickel deposits and magmatic type chromite deposits,while its Mesozoic to Cenozoic basalt belts show remarkable metallogenic specialization of lateritic bauxite deposits.Consequently,many giant metallogenic belts were formed,including the Southeast Asian tin belt,the Qinghai-Xizang Plateau rare metal metallogenic belt,the Tethyan porphyry Cu-Au-Mo metallogenic belt,the circum-Pacific porphyry Cu-Au-Mo metallogenic belt,the Southeast Asian lateritic bauxite metallogenic belt,the Deccan Plateau lateritic bauxite metallogenic belt in India,the Southeast Asian lateritic nickel metallogenic belt,and the Tethyan magmatic type chromite metallogenic belt—all of which are significant metallogenic belts in Asia continent.Future mineral exploration in Asia should focus primarily on the Precambrian mineralization of ancient cratons,the Paleozoic mineralization of the Central Asian-Mongolian orogenic belt,and the Mesozoic to Cenozoic mineralization of the Tethyan and circum-Pacific mobile belts.Asia's mining industry not only underpins its own economic growth but also propels global economic development and industrialization,contributing significantly to the world economy.Asia boasts the highest production value of minerals,the largest annual production of minerals,and the greatest trade value of mineral products among all the continents,having emerged as the trade center of global mineral products and the center of the mining industry economy.China is identified as one of the few countries that possess the most comprehensive kinds of minerals,and its mining industry has supported and driven the economic development and industrialization of Asia and even the world.Standing as the largest mineral producer worldwide,China ranked first in the production of 28 mineral commodities in the world in 2022.Besides,China exhibits the highest annual production value of minerals and the largest trade value of mineral products among all countries.Therefore,China's demand for global mineral products influences the global supply and demand patterns of minerals and the world economic situation. 展开更多
关键词 Mineral resource endowment Minerogenetic series Metallogenic specialization Carbonate-type REE deposits Weathering-type REE deposits Hard rock-type lithium deposits Laterite nickel deposits Crystalline graphite deposits Magmatic nickel deposits Significant metallogenic belt Mining industry development pattern Mineral exploration and exploitation World economy Contribution Asia continent
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空间亚频繁co-location模式的主导特征挖掘 被引量:12
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作者 马董 陈红梅 +1 位作者 王丽珍 肖清 《计算机应用》 CSCD 北大核心 2020年第2期465-472,共8页
空间co-location模式是一组空间特征的子集,它们的实例在邻域内频繁并置出现。通常,空间co-location模式挖掘方法假设空间实例相互独立,并采用空间实例参与到模式实例的频繁性(参与率)来度量空间特征在模式中的重要性,采用空间特征的最... 空间co-location模式是一组空间特征的子集,它们的实例在邻域内频繁并置出现。通常,空间co-location模式挖掘方法假设空间实例相互独立,并采用空间实例参与到模式实例的频繁性(参与率)来度量空间特征在模式中的重要性,采用空间特征的最小参与率(参与度)来度量模式的有趣程度,忽略了空间特征间的某些重要关系。因此为了揭示空间特征间的主导关系而提出主导特征co-location模式。现有主导特征模式挖掘方法是基于传统频繁模式及其团实例模型进行挖掘,然而,团实例模型可能会忽略非团的空间特征间的主导关系。因此,基于星型实例模型,研究空间亚频繁co-location模式的主导特征挖掘,以更好地揭示空间特征间的主导关系,挖掘更有价值的主导特征模式。首先,定义了两个度量特征主导性的指标;其次,设计了有效的主导特征co-location模式挖掘算法;最后,在合成数据集和真实数据集上通过大量实验验证了所提算法的有效性以及主导特征模式的实用性。 展开更多
关键词 空间数据挖掘 空间co-location模式 亚频繁co-location模式 主导特征 主导特征co-location模式
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领域驱动的高效用co-location模式挖掘方法 被引量:7
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作者 江万国 王丽珍 +1 位作者 方圆 陈红梅 《计算机应用》 CSCD 北大核心 2017年第2期322-328,共7页
空间并置(co-location)模式是指其实例在空间邻域内频繁共现的空间特征集的子集。现有的空间colocation模式挖掘的有趣性度量指标,没有充分地考虑特征之间以及同一特征的不同实例之间的差异;另外,传统的基于数据驱动的空间co-location... 空间并置(co-location)模式是指其实例在空间邻域内频繁共现的空间特征集的子集。现有的空间colocation模式挖掘的有趣性度量指标,没有充分地考虑特征之间以及同一特征的不同实例之间的差异;另外,传统的基于数据驱动的空间co-location模式挖掘方法的结果常常包含大量无用或是用户不感兴趣的知识。针对上述问题,提出一种更为一般的研究对象——带效用值的空间实例,并定义了新的效用参与度(UPI)作为高效用co-location模式的有趣性度量指标;将领域知识形式化为三种语义规则并应用于挖掘过程中,提出一种领域驱动的多次迭代挖掘框架;最后通过大量实验对比分析不同有趣性度量指标下的挖掘结果在效用占比和频繁性两方面的差异,以及引入基于领域知识的语义规则前后挖掘结果的变化情况。实验结果表明所提出的UPI度量是一种兼顾频繁和效用的更为合理的度量指标;同时,领域驱动的挖掘方法能有效地挖掘到用户真正感兴趣的模式。 展开更多
关键词 空间模式挖掘 co-location模式 高效用co-location模式 有趣性度量指标 领域驱动 语义规则
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