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Climatological Characteristics of the Moisture Budget and Their Anomalies over the Joining Area of Asia and the Indian-Pacific Ocean 被引量:5
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作者 柳艳菊 丁一汇 +1 位作者 宋亚芳 张锦 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2009年第4期642-655,共14页
The climatological characteristics of the moisture budget over the joining area of Asia and the IndianPacific Ocean (AIPO) and its adjacent regions as well as their anomalies have been estimated in this study. The m... The climatological characteristics of the moisture budget over the joining area of Asia and the IndianPacific Ocean (AIPO) and its adjacent regions as well as their anomalies have been estimated in this study. The main results are as follows. In the winter, the northeasterly moisture transport covers the extensive areas at the lower latitudes of the AIPO. The westerly and northerly moisture transport is the major source and the South Indian Ocean (SIO) is the moisture sink. In the summer, influenced by the southwesterly monsoonal wind, the crossequatorial southwesterly moisture transport across Somali originating from the SIO is transported through the Arabian Sea (AS), the Bay of Bengal (BOB), and the South China Sea (SCS) to eastern China. The AIPO is controlled by the southwesterly moisture transport. The net moisture influx over the AIPO has obvious interannual and interdecadal variations. From the mid- or late 1970s, the influxes over the SIO, the AS, the northern part of the western North Pacific (NWNP), and North China (NC) as well as South China (SC) begin to decrease abruptly, while those over Northeast China (NEC) and the Yangtze River-Huaihe River basins (YHRB) have increased remarkably. As a whole, the net moisture influxes over the BOB and the southern part of the western North Pacific (SWNP) in the recent 50 years take on a linear increasing trend. However, the transition timing for these two regions is different with the former being at the mid- or late 1980s and the latter occurring earlier, approximately at the early stage of the 1970s. The anomalous moisture source associated with the precipitation anomalies is different from the normal conditions of the summer precipitation. For the drought or flood years or the years of E1 Nifio and its following years, the anomalous moisture transport originating from the western North Pacific (WNP) is the vital source of the anomalous precipitation over eastern China, which is greatly related with the variation of the subtropical Pacific high. 展开更多
关键词 the joining area of Asia and the Indian-Pacific Ocean moisture transport and budget climatological characteristics ANOMALIES
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Climatological Characteristics of Cyclone Activity in Summer in East Asia and Its Effects on Rainfall in China
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作者 王艳玲 郭品文 《Meteorological and Environmental Research》 CAS 2010年第9期48-52,共5页
The spatial and temporal variation of cyclone activity in summer in East Asia have been studied,as well as the relationship between cyclone activity frequency,atmospheric circulation background field at 500 hPa and ra... The spatial and temporal variation of cyclone activity in summer in East Asia have been studied,as well as the relationship between cyclone activity frequency,atmospheric circulation background field at 500 hPa and rainfall in China.The results showed that cyclone activity in summer was mainly distributed in three regions,and cyclone activity frequency in the north of 25° N before the middle of 1970s was continuously higher than that after the middle of 1970s.The decadal variation of cyclone activity frequency was closely related to the anomaly of atmospheric circulation at 500 hPa.There was obvious negative anomaly in middle and high latitudes of East Asia before the middle of 1970s,prevailing meridional circulation,with the increase of cyclone activity.However,the atmospheric circulation situation was reverse after the middle of 1970s.Summer rainfall in Shandong Peninsula had significant decadal variability,experiencing wet and dry season,and wet(or dry) season was fit to the period of higher(or lower) cyclone activity frequency in the north of 25° N. 展开更多
关键词 Summer cyclone Activity frequency climatological characteristic RAINFALL China
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Some Annual Variation Characteristics for the Northern Hemispheric Monthly Mean Precipitation Fields
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作者 汤懋苍 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 1989年第2期186-201,共16页
By the utilization of monthly precipitation data from all stations in the Northern Hemisphere annexed to the 'World Survey of climatology, Vol. 1-15', the distributions of the maximum precipitation months (MPM... By the utilization of monthly precipitation data from all stations in the Northern Hemisphere annexed to the 'World Survey of climatology, Vol. 1-15', the distributions of the maximum precipitation months (MPM), the annual relative precipitation (ARP) and the monthly relative precipitation (percent of annual) in January and July are respectively mapped. Moreover the distributions of intermonthly relative precipitation variabilities from January to December are plotted as well. From these figures, the precipitation in the Northern Hemisphere may be classified into three types(continental, oceanic and transitional types) and 17 regions. The precipitation regime may also be divided into two patterns, the global and regional patterns. The global pattern consists of planetary front system and ITCZ and its inter-monthly variation shows the north-and-south shift of the rain belt; the regional pattern consists of the sea-land monsoon and plateau monsoon regime, in which the inter-monthly variation of rain belt shows a east-and-wcst shift. 展开更多
关键词 MPM Some Annual Variation characteristics for the Northern Hemispheric Monthly mean Precipitation Fields ARP
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Climatological characteristics of monsoons and tropical cyclone activities over China seas and their influences on hydrological and seasonal structures over the South China Sea
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作者 Chen Shangji National Marine Data and Information Service, State Oceanic Administration, Tianjin 300171, China 《Acta Oceanologica Sinica》 SCIE CAS CSCD 1993年第3期359-377,共19页
The aim of this paper is to study whether the features of perennial summer over the South China Sea remain constant all the year round or not , and whether there are any seasonal differences throughout the year or not... The aim of this paper is to study whether the features of perennial summer over the South China Sea remain constant all the year round or not , and whether there are any seasonal differences throughout the year or not. According to the characteristics of remarkable monsoon and frequent typhoon, the influences of monsoon and tropical cyclone on the hydrological features and the seasonal structure over the South China Sea are analysed by using examples. It may be considered that in the perennial summer area over the South China Sea, it is summer all the year round, but it does not remain constant throughout the year. On the basis of index dates of developing stages for winter and summer monsoons as well as the seasonal characteristics of typhoon frequency,the perennial summer season over the South China Sea may be divided into four periods, namely, early summer, midsummer, sweltering summer and late summer. The concrete classification and the hydrological seasonal feature of each period are discussed. 展开更多
关键词 China seas South China Sea MONSOON tropical cyclone typhoon climatological characteristic hydrological seansonal feature
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Climatic characteristics of high temperature in East China during 1961-2005 被引量:5
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作者 SHI Jun TANG Xu CUI Linli 《Journal of Geographical Sciences》 SCIE CSCD 2008年第3期283-294,共12页
Based on the daily maximum temperature data covering the period 1961-2005, temporal and spatial characteristics and their changing in mean annual and monthly high temperature days(HTDs)and the mean daily maximum tem... Based on the daily maximum temperature data covering the period 1961-2005, temporal and spatial characteristics and their changing in mean annual and monthly high temperature days(HTDs)and the mean daily maximum temperature(MDMT)during annual and monthly HTDs in East China were studied.The results show that the mean annual HTDs were 15.1 and the MDMT during annual HTDs was 36.3℃in the past 45 years.Both the mean annual HTDs and the MDMT during annual HTDs were negative anomaly in the1980s and positive anomaly in the other periods of time,oscillating with a cycle of about 12-15 years.The mean annual HTDs were more in the southern part,but less in the northern part of East China.The MDMT during annual HTDs was higher in Zhejiang,Anhui and Jiangxi provinces in the central and western parts of East China.The high temperature process(HTP) was more in the southwestern part,but less in northeastern part of East China.Both the HTDs and the numbers of HTP were at most in July,and the MDMT during monthly HTDs was also the highest in July.In the first 5 years of the 21st century,the mean annual HTDs and the MDMT during annual HTDs increased at most of the stations,both the mean monthly HTDs and the MDMT during monthly HTDs were positive anomalies from April to October,the number of each type of HTP generally was at most and the MDMT in each type of HTP was also the highest. 展开更多
关键词 climatic characteristics high temperature days (HTDs) mean daily maximum temperature (MDMT) during HTDs high temperature process (HTP) East China
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STATISTICAL CHARACTERISTICS OF TROPICAL CYCLONES MAKING LANDFALLS AND PASSING THROUGH LAKES IN CHINA 被引量:2
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作者 王晓芳 《Journal of Tropical Meteorology》 SCIE 2009年第1期63-67,共5页
By using the data of 1949 – 2001 (53 years) of Tropical Cyclone (TC) Yearbooks, statistical analyses are performed to study the climatic features of TCs making landfall and then passing through lakes (hereafter refer... By using the data of 1949 – 2001 (53 years) of Tropical Cyclone (TC) Yearbooks, statistical analyses are performed to study the climatic features of TCs making landfall and then passing through lakes (hereafter referred to as "L-TCs") in China. Results show that L-TCs can sustain a long time over land and the intensity is very strong during the course of landfall. Lakes can noticeably slow down the reduction of TC intensity, with the minimum pressure mostly maintained or decreased and the maximum velocity increased. The middle reach of the Yangtze River has the biggest TC dissipating rate as compared with the other areas where the TC is active. 展开更多
关键词 climatology tropical cyclones statistic characteristics landfall lakes
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Analysis on the psychological characteristics of patients with acute iridocyclitis
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作者 Wei Sun Fan Wu +2 位作者 Jun Kong Yukiko Nakahara Xiao-Yan Li 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2015年第3期635-636,共2页
【正】Dear Sir,I am Dr.Wei Sun,from the Department of Ophthalmology,the Fourth Affiliated Hospital of China Medical University,Eye Hospital of China Medical University,shenyang,Liaoning Province,China.I write to prese... 【正】Dear Sir,I am Dr.Wei Sun,from the Department of Ophthalmology,the Fourth Affiliated Hospital of China Medical University,Eye Hospital of China Medical University,shenyang,Liaoning Province,China.I write to present our study on the psychological characteristics of patients with acute iridocyclitis.Studies showed stimulation from patient’s external environment could influence their psychological state,persisting neural endocrine disorders that might lead to a series of physiological and psychological changes in the human body[1-6].It was confirmed many ocular diseases were 展开更多
关键词 Analysis on the psychological characteristics of patients with acute iridocyclitis mean
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Near-surface structure and energy characteristics of the Antarctic Circumpolar Current 被引量:3
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作者 GAO Libao YU Weidong +1 位作者 WANG Haiyuan LIU Yanliang 《Advances in Polar Science》 2013年第4期265-272,共8页
Historical surface drifter observations collected from the Southern Ocean are used to study the near-surface structure, variability, and energy characteristics of the Antarctic Circumpolar Current (ACC). A strong, n... Historical surface drifter observations collected from the Southern Ocean are used to study the near-surface structure, variability, and energy characteristics of the Antarctic Circumpolar Current (ACC). A strong, nearly zonal ACC combined with complex fronts dominates the circulation system in the Southern Ocean. Standard variance ellipses indicate that both the Agulhas Return Current and the East Australian Warm Current are stable supplements of the near-surface ACC, and that the anticyclonic gyre formed by the Brazil warm current and the Malvinas cold current is stable throughout the year. During austral winter, the current velocity increases because of the enhanced westerly wind. Aroused by the meridional motion of the ACC, the meridional velocity shows greater instability characteristics than the zonal velocity does over the core current. Additionally, the ACC exhibits an eastward declining trend in the core current velocity from southern Africa. The characteristics of the ACC are also argued from the perspective of energy. The energy distribution suggests that the mean kinetic energy (MKE), eddy kinetic energy (EKE), and are strong over the core currents of the ACC. However, in contrast, EKE/MKE suggests there is much less (more) eddy dissipation in regions with strong (weak) energy distribution. Both meridional and zonal energy variations are studied to illustrate additional details of the ACC energy characteristics. Generally, all the energy forms except EKE/MKE present west-east reducing trends, which coincide with the velocity statistics. Eddy dissipation has a much greater effect on MKE in the northern part of the Southern Ocean. 展开更多
关键词 mean structure energy characteristic ACC
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The hydrochemical characteristics and its significance of geothermal water in both sides of large fault: Taking northern section of the Liaokao fault in north China as an example 被引量:5
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作者 Bao-jian Zhang Tian Zhao +6 位作者 Yan-yan Li Yi-fei Xing Gui-ling Wang Jun Gao Xian-chun Tang Wen-zhen Yuan Dai-lei Zhang 《China Geology》 2019年第4期512-521,共10页
Based on comparative analysis on hydrochemical characteristics of geothermal water in the north part of Liaokao fault,this research focuses on studying the indicative significance of hydrochemical characteristics for ... Based on comparative analysis on hydrochemical characteristics of geothermal water in the north part of Liaokao fault,this research focuses on studying the indicative significance of hydrochemical characteristics for the formation of geothermal water.The result shows that:(1)There is no obvious hydraulic connection between the karst geothermal water(occurred in the east part of the Liaokao fault)and the sandstone geothermal water(occurred in the west part of Liaokao fault).(2)In a close hydrological environment,caused by tectonic activities,geothermal water remains longer time in reservoir,hence the water-rock interaction is more complete,with high degree of concentrations,whereas the renewable capacity of the water is weaker.(3)There is no high temperature mantle source fluid mixed in the geothermal water.Karst geothermal water occurred deep circulatory convection along Liaokao fault and its secondary fault,therefore there is deep crust source fluid added into the geothermal water,closer to the Liaokao fault,the greater affected by the deep crust fluid.However,sandstone geothermal water has weak deep circulatory convection. 展开更多
关键词 GEOTHERMAL survey engineering Large-scale FAULT HYDROCHEMISTRY GEOTHERMAL water ZONAL characteristics Indicative meanING Liaokao FAULT North China
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The New Detection and the Basic Characteristics of the Structural System of Taiwan Region of China—Using the Earth Satellite's Remote-sensing Images to Explain the Structural System of Taiwan Region of China
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作者 Hu Dongsheng Zhang Huajing 《工程科学(英文版)》 2006年第3期29-36,共8页
This text uses the regional geological investigation data and the remote sensing image data of earth-satellite remote sensing to synthetically analyze the structural system of Taiwan region of China. Authors detection... This text uses the regional geological investigation data and the remote sensing image data of earth-satellite remote sensing to synthetically analyze the structural system of Taiwan region of China. Authors detection-marked and assurance-marked and divided 5 kinds of structural system of the Taiwan region: (1) the wreath-shaped structural system, (2) the N-N-E oriented structural system, (3) the S-N oriented structural system, (4) the N-E oriented structural system, (5) the arc-shaped structural system. Combination of the texture faces and associated method were adopted to recover and reconstruct the structural evolution sequences and the formation periods. In this paper, problems such as the development process in geology etc. are also discussed, contributing new information to research the structural field of the East Asia and its tectonic plate movements and structural actions inside the land plate . 展开更多
关键词 中国 台湾省 区域地质特征 基本格局 构造演化 构造系统 遥感图象 地球卫星
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A MARKOVIAN APPROACH TO DETERMINING PROCESS MEANS WITH DUAL QUALITY CHARACTERISTICS
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作者 Mohammad T.KHASAWNEH Shannon R.BOWLING Byung Rae CHO 《Journal of Systems Science and Systems Engineering》 SCIE EI CSCD 2008年第1期66-85,共20页
This paper studies a production system where products are produced continuously and whose specification limits are specified for screening inspection. In this paper, we consider dual quality characteristics and differ... This paper studies a production system where products are produced continuously and whose specification limits are specified for screening inspection. In this paper, we consider dual quality characteristics and different costs associated with each quality characteristic that falls below a lower specification limit or above an upper specification limit. Due to these different costs, the expected total profit will greatly depend on the process parameters, especially a process mean. This paper develops a Markovian-based model for determining the optimum process means with the consideration of dual quality characteristics in a single-stage system. The proposed model is then illustrated through a numerical example and sensitivity analysis is performed to validate the model. The results showed that the optimum process mean for both quality characteristics have a significant effect on the performance of the system. Since the literature survey shows that dealing with multi-quality characteristics is extremely limited, the proposed model, coupled with the Markovian approach, provides a unique contribution to this field. 展开更多
关键词 Single-stage production optimum process mean Markov chains dual quality characteristics
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ROLE IN MOISTURE TRANSPORTATION OF SEASONAL MEAN AND INTRASEASONAL OSCILLATIONS IN ASIAN SUMMER MONSOON AREA——LONG-TERM AVERAGE CHARACTERISTICS
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作者 徐建军 何金海 朱刚 《Acta meteorologica Sinica》 SCIE 1993年第3期347-354,共8页
By use of the May—September 1980—1986 ECMWF daily data of u,v,r and T at 850 hPa,a comparative analysis is performed of basic features of moisture transportation at seasonal mean,quasi-40-day,-biweekly,and-weekly os... By use of the May—September 1980—1986 ECMWF daily data of u,v,r and T at 850 hPa,a comparative analysis is performed of basic features of moisture transportation at seasonal mean,quasi-40-day,-biweekly,and-weekly oscillations,indicating that the seasonal mean transfer plays a decisive role in the moisture flux over the Asian monsoon region,displaying the integer of the monsoon systems there in character;that the transport related to these tropical intraseasonal oscillations are of equal importance in the monsoon period except the difference in their behaviors,i.e.,the transfer shows considerable relative independence in the South-and East-Asian systems;and that the transport at all these intraseasonal oscillations is found to be feeble at equatorial latitudes with little or no influence on each other for both hemispheres. 展开更多
关键词 ASIA LONG-TERM AVERAGE characteristics ROLE IN MOISTURE TRANSPORTATION OF SEASONAL mean AND INTRASEASONAL OSCILLATIONS IN ASIAN SUMMER MONSOON AREA
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THE OSCILLATION OF CERTAIN ZONAL MEAN CHARACTERISTICS OF MOTION ON A SPHERIC EARTH'S ATMOSPHERE——PART 2:ANISOTROPIC QUASI-EDDY MOTION
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作者 谢义炳 《Acta meteorologica Sinica》 SCIE 1989年第1期17-24,共8页
This paper is an extension of the author's paper (Xie,1982) to the spherical earth.It is found that the simi- lar results are obtained under the assumption of isotropic distribution of horizontal kinetic energy al... This paper is an extension of the author's paper (Xie,1982) to the spherical earth.It is found that the simi- lar results are obtained under the assumption of isotropic distribution of horizontal kinetic energy along the zonal and meridional directions.It points out the limitation of the results already obtained and paves the path for the approach of anisotropie semi-eddy or quasi-eddy motion of the atmosphere. 展开更多
关键词 PART 2 THE OSCILLATION OF CERTAIN ZONAL mean characteristics OF MOTION ON A SPHERIC EARTH’S ATMOSPHERE
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基于改进K-means聚类的轨道交通基础设施分布式光伏发电典型场景生成及出力特性分析 被引量:1
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作者 陈凯 雷琪 李豆萌 《电气工程学报》 CSCD 北大核心 2024年第2期364-372,共9页
受限于自然条件,光伏出力具有很强的随机性。为准确评估轨道交通基础设施分布式光伏发电的光伏出力特性,提出一种基于改进K-means聚类算法的轨道交通基础设施分布式光伏发电典型场景生成方法,并基于此进行光伏出力特性分析。首先,基于... 受限于自然条件,光伏出力具有很强的随机性。为准确评估轨道交通基础设施分布式光伏发电的光伏出力特性,提出一种基于改进K-means聚类算法的轨道交通基础设施分布式光伏发电典型场景生成方法,并基于此进行光伏出力特性分析。首先,基于分布式光伏发电设施以及气象数据,利用PVsyst软件模拟光伏发电出力数据。然后,针对基本K-means聚类算法聚类参数和初始聚类中心盲目性高的问题,结合聚类有效性指标(Density based index,DBI)和层次聚类对其进行改进并利用改进K-means聚类算法生成光伏典型日出力场景。最后,基于华中地区某地轨道交通基础设施分布式光伏系统对所提方法的有效性和优越性进行验证,并通过定性和定量分析各典型场景的出力特性揭示轨道交通基础设施分布式光伏出力的规律和特点。 展开更多
关键词 分布式光伏出力 改进K-means聚类算法 典型出力场景 出力特性分析
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基于空间约束K⁃means模型的长三角地区生态系统服务时空格局及功能分区研究 被引量:1
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作者 汪勇政 余浩然 陆林 《生态学报》 CAS CSCD 北大核心 2024年第16期7087-7104,共18页
科学认知生态服务功能的时空演变规律以及合理划分生态系统服务簇的空间分类对于生态系统管理和政策制定至关重要。旨在揭示长三角城市群2000—2020年间生物多样性维护、产水量、碳储存、土壤保持、植被净初级生产力、粮食产量的时空演... 科学认知生态服务功能的时空演变规律以及合理划分生态系统服务簇的空间分类对于生态系统管理和政策制定至关重要。旨在揭示长三角城市群2000—2020年间生物多样性维护、产水量、碳储存、土壤保持、植被净初级生产力、粮食产量的时空演变特征、权衡关系,并利用空间约束K⁃means模型(SC K⁃means)聚类识别生态系统服务簇,划分生态系统服务功能管理区。研究结果表明:(1)生物多样性维护、产水量、碳储存、土壤保持、植被净初级生产力整体呈“西南山地高,东北平原低”空间格局,粮食产量与之相反;(2)六类生态系统服务空间变化差异体现出明显人类活动与自然气候主导,且粮食产量与其他生态系统服务表现为权衡关系;(3)基于SC K⁃means识别生态系统服务簇的结果将研究区划分为为粮食主产区、人类活动密集区、皖浙生态保护区、大别山生态保护区、皖江生态过渡带、长三角核心保护区六类生态功能区,针对各分区提出差异化生态管控建议。研究可为国土空间规划分区引导提供理论依据与实践参考。 展开更多
关键词 生态系统服务 权衡关系 时空特征 生态系统服务簇 空间约束K⁃means模型(SC K⁃means)
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基于改进K-Means算法的电动汽车充电负荷特性分析 被引量:1
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作者 李俊达 陈姝敏 +2 位作者 王天安 张玎一 吴全才 《云南电力技术》 2024年第3期10-13,19,共5页
电动汽车充电行为具有较大的随机性,一定程度上影响电网的稳定运行和规划。为更准确地分析电动汽车充电负荷的特性,提出一种基于改进K-Means算法的聚类分析方法。针对K-Means算法在初始聚类中心选取上的随机性和不稳定性,首先利用Mini B... 电动汽车充电行为具有较大的随机性,一定程度上影响电网的稳定运行和规划。为更准确地分析电动汽车充电负荷的特性,提出一种基于改进K-Means算法的聚类分析方法。针对K-Means算法在初始聚类中心选取上的随机性和不稳定性,首先利用Mini Batch K-Means算法的随机抽样能力优化初始聚类中心的选择,随后结合K-Means算法进行迭代优化,有效解决K-Means算法聚类结果不稳定的问题。以云南某城市充电桩负荷数据进行算例分析,结果表明,所提算法相比传统方法相比能更加准确地对多个不同负荷特性的用户进行分类,从而更有效地指导有序用电管理策略的制定。 展开更多
关键词 K-meanS算法 Mini Batch K-means算法 负荷特性分析
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基于K-Means聚类方法的北京市公共交通通勤乘客特征挖掘
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作者 卢宇浩 朱墨 马毅林 《交通工程》 2024年第10期9-16,共8页
北京市公共交通系统在满足居民出行需求的同时,产生海量的出行数据,为客流分析奠定数据基础,而地理信息技术、机器学习为数据处理与分析提供新的思路。基于2021年10月北京1周公共交通票务数据,通过多种清洗手段和补全算法对源数据进行处... 北京市公共交通系统在满足居民出行需求的同时,产生海量的出行数据,为客流分析奠定数据基础,而地理信息技术、机器学习为数据处理与分析提供新的思路。基于2021年10月北京1周公共交通票务数据,通过多种清洗手段和补全算法对源数据进行处理,通过时间阈值和空间阈值提取出行链,从时间、空间、频次3个维度分析客流特性并构建聚类变量。采用K-Means算法将常乘客分为5类,分析各类别乘客特征规律,提取出稳态常乘客类别,为常乘客的分析提供新的思路,有助于界定公交的主要客流来源出行特征,为改善公交运营,提升公交服务水平提供支撑。 展开更多
关键词 公交IC卡 地铁AFC系统 出行特征 K-meanS算法 乘客分类
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跟踪窗自适应的Mean Shift目标跟踪算法 被引量:16
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作者 刘晴 唐林波 赵保军 《系统工程与电子技术》 EI CSCD 北大核心 2012年第2期409-412,共4页
针对Mean Shift算法不能很好地跟踪尺度变化目标的缺点,提出一种将Mean Shift算法和目标几何特征相结合的目标跟踪算法。该方法在Mean Shift框架下提取目标的几何特征,根据目标的面积和型心坐标对跟踪窗的位置和大小进行修正,最后更新Me... 针对Mean Shift算法不能很好地跟踪尺度变化目标的缺点,提出一种将Mean Shift算法和目标几何特征相结合的目标跟踪算法。该方法在Mean Shift框架下提取目标的几何特征,根据目标的面积和型心坐标对跟踪窗的位置和大小进行修正,最后更新Mean Shift的目标模板。通过大量实验仿真证明,改进的算法能很好地跟踪尺度变化的目标,对目标的仿射变化和非刚性的形态变化具有有效性和鲁棒性。 展开更多
关键词 目标跟踪 mean SHIFT 几何特征 跟踪窗自适应
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融合K-means与高斯混合模型的驾驶风格聚类研究 被引量:17
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作者 刘通 付锐 +1 位作者 张名芳 田顺 《中国安全科学学报》 CAS CSCD 北大核心 2019年第12期40-45,共6页
为研究驾驶员的跟车特性,探究驾驶员风格划分方法,采集50名驾驶员的实车试验数据,选取平均跟车时距和平均制动时距为二维向量,建立基于K-means聚类结果的高斯混合模型(GMM)并分析不同风格驾驶员的聚类结果。研究表明:样本数据聚为3类时... 为研究驾驶员的跟车特性,探究驾驶员风格划分方法,采集50名驾驶员的实车试验数据,选取平均跟车时距和平均制动时距为二维向量,建立基于K-means聚类结果的高斯混合模型(GMM)并分析不同风格驾驶员的聚类结果。研究表明:样本数据聚为3类时的平均轮廓系数为0. 45,将驾驶员划分为冒进型、平稳型、保守型3类时聚类效果较好;冒进型驾驶员倾向于选择较小的跟车时距和制动时距,保守型驾驶员的跟车及制动时距则普遍较大,模型聚类结果更加柔性,样本区分度更高。 展开更多
关键词 驾驶风格 K-meanS聚类 高斯混合模型(GMM) 跟车特性 制动特点
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基于K-means聚类的路面裂缝分割算法 被引量:27
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作者 李鹏 李强 +1 位作者 马味敏 蒋威 《计算机工程与设计》 北大核心 2020年第11期3143-3147,共5页
针对传统分割算法在非均匀背景中存在低抗噪性及高复杂性的问题,将聚类分析和区域生长算法相结合,提出基于K-means聚类的路面裂缝区域生长分割算法。依据图像灰度像素特征进行裂缝目标聚类,融合裂缝几何纹理特征将聚类中心值作为种子点... 针对传统分割算法在非均匀背景中存在低抗噪性及高复杂性的问题,将聚类分析和区域生长算法相结合,提出基于K-means聚类的路面裂缝区域生长分割算法。依据图像灰度像素特征进行裂缝目标聚类,融合裂缝几何纹理特征将聚类中心值作为种子点区域生长,经过形态学滤波优化处理完成精确分割。仿真结果表明,该算法在视觉上裂缝分割的准确率提高,查准率曲线和受试者工作特征曲线的评价结果也表明,该算法与传统边缘检测算法相比,具有环境适应能力强、识别准确率高以及性能稳定等优势。 展开更多
关键词 裂缝检测 K-meanS聚类 区域生长 查准率曲线 受试者工作特征曲线
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