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秦蜀古道三维扫描测量精度分析 被引量:3
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作者 南竣祥 梁爽 +3 位作者 李海泉 李俊 周磊 白亚伟 《测绘与空间地理信息》 2017年第3期213-214,217,220,共4页
数据测量是秦蜀古道遗存调查中一个重要的环节,测量数据的精度是后续实物复原的关键,决定着后续数字化模型的精度及还原栈道遗存的关键。本文基于Leica P40三维激光扫描技术,在采集后的点云数据及建立的模型数据上分别量测栈道基本几何... 数据测量是秦蜀古道遗存调查中一个重要的环节,测量数据的精度是后续实物复原的关键,决定着后续数字化模型的精度及还原栈道遗存的关键。本文基于Leica P40三维激光扫描技术,在采集后的点云数据及建立的模型数据上分别量测栈道基本几何信息,比对分析数据误差,指出模型数据量测数据精度高于点云数据量测精度,且测量结果满足传统文物的测量精度,可以对人员无法到达区域的文物本体数据进行数据量测,为文物保护研究提供支撑。 展开更多
关键词 三维激光扫描 文物 数据量测 精度
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APPLICATION OF GREY SYSTEM THEORY TO PROCESSING OF MEASURING DATA IN REVERSE ENGINEERING 被引量:3
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作者 平雪良 周儒荣 安鲁陵 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2003年第1期36-41,共6页
The processing of measuri ng data plays an important role in reverse engineering. Based on grey system the ory, we first propose some methods to the processing of measuring data in revers e engineering. The measured d... The processing of measuri ng data plays an important role in reverse engineering. Based on grey system the ory, we first propose some methods to the processing of measuring data in revers e engineering. The measured data usually have some abnormalities. When the abnor mal data are eliminated by filtering, blanks are created. The grey generation an d GM(1,1) are used to create new data for these blanks. For the uneven data sequ en ce created by measuring error, the mean generation is used to smooth it and then the stepwise and smooth generations are used to improve the data sequence. 展开更多
关键词 reverse engineering gr ey system theory DIGITIZATION data processing grey generation
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MEASUREMENT TECHNOLOGY OF HEAT AND COOL
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作者 朱春玲 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2001年第2期245-249,共5页
The popularization of large scale central air conditioning system (CACS) has brought forward a new pro blem,i.e. how to measure the cooling and heating quantum accurately. This problem will directly affect the qua ... The popularization of large scale central air conditioning system (CACS) has brought forward a new pro blem,i.e. how to measure the cooling and heating quantum accurately. This problem will directly affect the qua lity of modern property management. So the study on the technology of measuring heat and cool is very necessary. In this paper, the detailed thermal analysis and the mathematical model of relative parameters that affect the measurement of heat and cool are discussed. A sample instrument based on the model is made, After the trial use by several customers, the device is proved to be practical, worthwhile and of good capacity. 展开更多
关键词 central air conditioning measurement data acquisition single chip
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Applied research on reliable increase measures of CNC lathes 被引量:4
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作者 于捷 贾亚洲 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2005年第2期218-220,共3页
According to the reliable data of sixteen CNC lathes, each reliable index of the serial CNC lathes is evaluated before tackling and after tackling. According to the failure analysis, reliable improvement measures of t... According to the reliable data of sixteen CNC lathes, each reliable index of the serial CNC lathes is evaluated before tackling and after tackling. According to the failure analysis, reliable improvement measures of the serial CNC lathes are put forward. 展开更多
关键词 CNC lathes reliability increasement measure evaluation index IMPROVEMENT REDESIGN FAILURE tackling
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Estimation of Geodetic Parameters with VLBI Data of Last 5 Years 被引量:4
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作者 WEI Erhu LIU Jingnan SHI Chuang 《Geo-Spatial Information Science》 2007年第1期12-16,共5页
The meaning to research the potential of VLBI for geodetic applications is summarized. And the observation models and their related parameters of geodetic interest are investigated. Then, the principle and method of u... The meaning to research the potential of VLBI for geodetic applications is summarized. And the observation models and their related parameters of geodetic interest are investigated. Then, the principle and method of using the random model in VLBI data processing are investigated. With the world wide VLBI data from 2000-2004, the conditions to compute the parameters of geodetic interest are introduced, and so are the computing methods and processes. And the computed resuits of the parameters of geodetic interest are analyzed. 展开更多
关键词 VLBI observation model parameters of geodetic interest random model computation and analysis
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Wavefield continuation datuming using a near surface model 被引量:3
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作者 Cui Xingfu Li Hongbing Hu Ying Liang Hong Qi Li 《Applied Geophysics》 SCIE CSCD 2007年第2期94-100,共7页
When topography and low velocity zone differences vary greatly, conventional vertical static time shifts will cause wavefield distortion and influence wave equation seismic imaging for seismic data acquired on a compl... When topography and low velocity zone differences vary greatly, conventional vertical static time shifts will cause wavefield distortion and influence wave equation seismic imaging for seismic data acquired on a complex near surface. In this paper, we propose an approach to datum correction that combines a joint tomography inversion with wavefield continuation to solve the static problem for seismic data on rugged acquisition topography. First, the near surface model is obtained by refracted wave tomography inversion. Second, the wavefield of sources and receivers are continued downward and upward to accomplish datum correction starting from a flat surface and locating the datum above topography. Based on the reciprocal theorem, Huygens' and Fresnel principles, the location of sources and receivers, and regarding the recorded data on the surface as a secondary emission, the sources and receivers are upward-continued to the datum above topography respectively. Thus, the datum correction using joint tomography inversion and wavefield continuation with the condition of a complex near surface is accomplished. 展开更多
关键词 Complex near surface tomography inversion wavefield continuation datum correction.
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Spatio-temporal Difference and Influencing Factors of Environmental Adaptability Measurement of Human-sea Economic System in Liaoning Coastal Area 被引量:6
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作者 LI Bo SHI Zhaoyuan TIAN Chuang 《Chinese Geographical Science》 SCIE CSCD 2018年第2期313-324,共12页
Adaptability theory is an important tool to analyze the degree, mechanism and process of interaction between human and environment, which provides a new perspective for the research of sustainability assessment. Based... Adaptability theory is an important tool to analyze the degree, mechanism and process of interaction between human and environment, which provides a new perspective for the research of sustainability assessment. Based on the entropy weight-TOPSIS method and the panel Tobit model from the perspective of adaptability, spatio-temporal difference and influencing factors of environmental adaptability assessment of human-sea economic system in Liaoning coastal area was measured by using the city panel data from 2000 to 2014. The results indicate that: 1) The environmental adaptability of human-sea economic system in Liaoning coastal area rose slowly from 2000 to 2014, the developing trend of each city was linearly related, and Dalian was in a leading position. 2) The different adaptability elements and adaptability subsystem show polarization phenomenon and completely different regional evolution characteristics. The adaptability of human-sea environment system and human-sea economic system rose slowly and had the characteristics of linear relationship, and the adaptability of human-sea environment system is the main reason for the difference of environmental adaptability of human-sea economic system. 3) Science and technology, environmental management, marine economic development level, port construction are the driving factors of the healthy development of environmental adaptability of urban human-sea economic system. 展开更多
关键词 human-sea economic system ADAPTABILITY human-sea environment system influencing factors Liaoning coastal area
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Small Target Extraction Based on Independent Component Analysis for Hyperspectral Imagery 被引量:3
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作者 LU Wei YU Xuchu 《Geo-Spatial Information Science》 2006年第2期103-107,共5页
A small target detection approach based on independent component analysis for hyperspectral data is put forward. In this algorithm, firstly the fast independent component analysis(FICA) is used to collect target infor... A small target detection approach based on independent component analysis for hyperspectral data is put forward. In this algorithm, firstly the fast independent component analysis(FICA) is used to collect target information hided in high-dimensional data and projects them into low-dimensional space.Secondly, the feature images are selected with kurtosis .At last, small targets are extracted with histogram image segmentation which has been labeled by skewness. 展开更多
关键词 fast independent component analysis SKEWNESS KURTOSIS target extraction
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Application of GPS technology to build a mine-subsidence observation station 被引量:16
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作者 LU Wei-cai CHENG Shi-guang +1 位作者 YANG Hai-sheng LIU Da-peng 《Journal of China University of Mining and Technology》 EI 2008年第3期377-380,共4页
We propose the design of an observation station to establish a reliable datum for displacement and deformation analysis at the first working-face subsidence observation station of Liuzhuang Mine. The design considers ... We propose the design of an observation station to establish a reliable datum for displacement and deformation analysis at the first working-face subsidence observation station of Liuzhuang Mine. The design considers various geologic and mining con-ditions. Having analyzed the aims of the joint survey and the comprehensive survey, we propose design principles, and work modes, for adopting GPS technology as the position measuring technique to be used in these two stages. Baseline vectors and spatial ad-justments of the GPS network were calculated after study of data processing and quality estimation methods. A coordinate system transformation and error estimates of the transformed GPS network data are discussed. The error estimates in all stages show that the GPS control network of the observation station has sufficient accuracy and is highly efficient. The network thus provides a reli-able datum for analyzing the laws of surface displacement and deformation induced by mining. 展开更多
关键词 GPS subsidence observation station initial observation data processing flow quality evaluating
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The Influence of Wave State and Sea Spray on Drag Coefficient from Low to High Wind Speeds 被引量:2
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作者 SHI Jian ZHONG Zhong +3 位作者 LI Xunqiang JIANG Guorong ZENG Wenhua LI Yan 《Journal of Ocean University of China》 SCIE CAS 2016年第1期41-49,共9页
Ocean waves alter the roughness of sea surface,and sea spray droplets redistribute the momentum flux at the air-sea interface.Hence,both wave state and sea spray influence sea surface drag coefficient.Based on the new... Ocean waves alter the roughness of sea surface,and sea spray droplets redistribute the momentum flux at the air-sea interface.Hence,both wave state and sea spray influence sea surface drag coefficient.Based on the new sea spray generation function which depends on sea surface wave,a wave-dependent sea spray stress is obtained.According to the relationship between sea spray stress and the total wind stress on the sea surface,a new formula of drag coefficient at high wind speed is acquired.With the analysis of the new drag coefficient,it is shown that the drag coefficient reduces at high wind speed,indicating that the sea spray droplets can limit the increase of drag coefficient.However,the value of high wind speed corresponding to the initial reduced drag coefficient is not fixed,and it depends on the wave state,which means the influence of wave cannot be ignored.Comparisons between the theoretical and measured sea surface drag coefficients in field and laboratory show that under different wave ages,the theoretical result of drag coefficient could include the measured data,and it means that the new drag coefficient can be used properly from low to high wind speeds under any wave state condition. 展开更多
关键词 wave state sea spray drag coefficient
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Semiparametric Regression and Model Refining 被引量:13
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作者 SUN Haiyan WU Yun 《Geo-Spatial Information Science》 2002年第4期10-13,共4页
This paper presents a semiparametric adjustment method suitable for general cases.Assuming that the regularizer matrix is positive definite,the calculation method is discussed and the corresponding formulae are presen... This paper presents a semiparametric adjustment method suitable for general cases.Assuming that the regularizer matrix is positive definite,the calculation method is discussed and the corresponding formulae are presented.Finally,a simulated adjustment problem is constructed to explain the method given in this paper.The results from the semiparametric model and G_M model are compared.The results demonstrate that the model errors or the systematic errors of the observations can be detected correctly with the semiparametric estimate method. 展开更多
关键词 model error systematric error semiparametric regression model refine regularizer matrix smoothing parameter
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Quality Analysis of Dairy Herd Improvement Data from Henan Province 被引量:1
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作者 Zhen ZHANG Xiaoli REN +3 位作者 Lei YAN Yuefei YAN Fanjun GENG Yanqin SUN 《Agricultural Science & Technology》 CAS 2017年第1期151-155,188,共6页
The dairy herd improvement data from Henan Province were analyzed statistically to establish screening criteria for relevant data, thereby laying a foundation for genetic evaluation of dairy cows. With the 2 152 451 t... The dairy herd improvement data from Henan Province were analyzed statistically to establish screening criteria for relevant data, thereby laying a foundation for genetic evaluation of dairy cows. With the 2 152 451 test-day records about 155 893 Chinese Holstein dairy cows collected by the Henan Dairy Herd Improvement Center from January 2008 to April 2016, the dynamics of test times during a complete lactation, test interval during a complete lactation, days in milk (DIM) of first test-day record, daughter descendant number and herd number of bull, age at first calving and pedigree integrity rate among different years and different herd sizes were analyzed by MEANS order of SAS 9.4. In addition, the data that were applicable to genetic evaluation were screened by SQL program. The results showed that during 2008-2015, the number of cow individuals participating in DHI in Henan Province increased from 7 379 to 93 706; the test-day milk yield increased from 19.91 to 24.05 kg; the somatic cell count reduced from 411.09×10^3 to 277.08×10^3 cells/ml; the percentage of cows with DIM ranging from 5-305 d reached 70.92%; the average test times increased from 3.20 to 6.31 times; the test interval decreased from 70.22 to 33.83 d; the dairy cows with age at first calving of 25 months were dominant, accounting for 12.57%; the bulls whose daughter descendant number was 20 or more and the daughters were distributed in 10 or more farms accounted for 6.05%; the one-generation pedigree integrity rate was 82.54%; the percentage of data that could be used for genetic evaluation was screened as 20.67%, which was lower than the results of other similar studies. 展开更多
关键词 Dairy herd improvement data quality Test times Test interval DIM of first test-day record Daughter descendant number and herd number of bull age at first calving Pedigree integrity rate
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Study of S-wave ray elastic impedance for identifying lithology and fluid
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作者 龚雪萍 张峰 +1 位作者 李向阳 陈双全 《Applied Geophysics》 SCIE CSCD 2013年第2期145-156,235,共13页
In this paper, we derive an approximation of the SS-wave reflection coefficient and the expression of S-wave ray elastic impedance (SREI) in terms of the ray parameter. The SREI can be expressed by the S-wave incide... In this paper, we derive an approximation of the SS-wave reflection coefficient and the expression of S-wave ray elastic impedance (SREI) in terms of the ray parameter. The SREI can be expressed by the S-wave incidence angle or P-wave reflection angle, referred to as SREIS and SREIP, respectively. Our study using elastic models derived from real log measurements shows that SREIP has better capability for lithology and fluid discrimination than SREIS and conventional S-wave elastic impedance (SEI). We evaluate the SREIP feasibility using 25 groups of samples from Castagna and Smith (1994). Each sample group is constructed by using shale, brine-sand, and gas-sand. Theoretical evaluation also indicates that SRE1P at large incident angles is more sensitive to fluid than conventional fluid indicators. Real seismic data application also shows that SRE1P at large angles calculated using P-wave and S-wave impedance can efficiently characterize tight gas-sand. 展开更多
关键词 S-WAVE IMPEDANCE ray parameter lithology identification fluid indicator
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Processing of measurement while drilling data for rock mass characterization 被引量:4
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作者 Babaei Khorzoughi Mohammad Hall Robert 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2016年第6期989-994,共6页
The information extracted from monitoring of rotary blasthole drills helps to optimize the overall mining operation. Rock hardness, drillability, blastability and specific energy of drilling are examples of parameters... The information extracted from monitoring of rotary blasthole drills helps to optimize the overall mining operation. Rock hardness, drillability, blastability and specific energy of drilling are examples of parameters that have been estimated in the past using measurement while drilling techniques. In order to be able to properly utilize measurement while drilling techniques, it is important to properly collect, analyze and interpret extracted data. This paper deals with processing of measurement while drilling data such as rate of penetration, rotary speed, rotary torque and pulldown force collected from rotary blasthole drills.Different methods are discussed to calculate a true rate of penetration which is the most important monitored drill variable for use in rock mass characterization. Then specific energy of drilling is defined and calculated based on electrical and mechanical inputs and the results are compared. The results show that specific energy of drilling can be estimated using the drill's primary drive systems' electrical responses with good accuracy when compared to values based on mechanical inputs. 展开更多
关键词 Measurement while drilling Rotary blasthole drill Specific energy Rate of penetration
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Calculation of Significant Wave Height Using the Linear Mean Square Estimation Method 被引量:2
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作者 GAO Yangyang YU Dingyong +1 位作者 LI Cuilin XU Delun 《Journal of Ocean University of China》 SCIE CAS 2010年第4期327-332,共6页
Significant wave height is an important criterion in designing coastal and offshore structures.Based on the orthogonality principle, the linear mean square estimation method is applied to calculate significant wave he... Significant wave height is an important criterion in designing coastal and offshore structures.Based on the orthogonality principle, the linear mean square estimation method is applied to calculate significant wave height in this paper.Twenty-eight-year time series of wave data collected from three ocean buoys near San Francisco along the California coast are analyzed.It is proved theoretically that the computation error will be reduced by using as many measured data as possible for the calculation of significant wave height.Measured significant wave height at one buoy location is compared with the calculated value based on the data from two other adjacent buoys.The results indicate that the linear mean square estimation method can be well applied to the calculation and prediction of significant wave height in coastal regions. 展开更多
关键词 significant wave height linear mean square estimation method orthogonality principle
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Identification of Ice Elevation Change of the Shuiguan River No.4 Glacier in the Qilian Mountains,China 被引量:14
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作者 LI Jing LIU Shiyin SHANGGUAN Donghui ZHANG Yinsong 《Journal of Mountain Science》 SCIE CSCD 2010年第4期375-379,共5页
GPS measurement,an effective method for surveying glacier surface topography,has been applied in some glaciers for many years.The Shuiguan River No.4 glacier,a small glacier with its area of 1.84 km2 in 1972,located i... GPS measurement,an effective method for surveying glacier surface topography,has been applied in some glaciers for many years.The Shuiguan River No.4 glacier,a small glacier with its area of 1.84 km2 in 1972,located in the east of the Qilian Mountains,China,was selected to study its ice elevation change using GPS measurement in 2007.This study was conducted on the ablation area with GPS-measured area 0.5 km2.The ice elevation change of the glacier was obtained by comparing the DEM obtained by a 1:50 000 topographic map made in 1972 with the DEM by GPS-measured data acquired in 2007.The differences of the two DEMs showed the thinning condition of the glacier was apparent.The mean thinning was 15±8 m with the mean thinning rate of 0.42±0.22 m a-1 for 1972-2007 in the measurement area,which equaled 0.38±0.20 m yr-1 in water equivalent(w.e.).The prominent thinning occurred on the south part of the glacier,which was the area near the glacier terminus with the maximum thinning of 41±8 m.Assuming the thinning value of 15±8 m for the glacier area below 4640 m a.s.l.,the wasting ice mass was calculated to be 6.4±3.2×10-3 km3 for 1972-2007,corresponding to 5.7±2.8×10-3 km3 w.e.,which meant that the montane runoff released by the glacier was at least 5.7±2.8×106 m3 between 1972-2007. 展开更多
关键词 GPS RTK DEM Glacier mass balance Mountane runoff
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Life prediction of ZPW-2000A track circuit equipment based on SVDD and gray prediction 被引量:2
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作者 WANG Rui-feng JIA Nan 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2018年第4期373-379,共7页
Evaluation of the health state and prediction of the remaining life of the track circuit are important for the safe operation of the equipment of railway signal system.Based on support vector data description(SVDD)and... Evaluation of the health state and prediction of the remaining life of the track circuit are important for the safe operation of the equipment of railway signal system.Based on support vector data description(SVDD)and gray prediction,this paper illustrates a method of life prediction for ZPW-2000A track circuit,which combines entropy weight method,SVDD,Mahalanobis distance and negative conversion function to set up a health state assessment model.The model transforms multiple factors affecting the health state into a health index named H to reflect the health state of the equipment.According to H,the life prediction model of ZPW-2000A track circuit equipment is established by means of gray prediction so as to predict the trend of health state of the equipment.The certification of the example shows that the method can visually reflect the health state and effectively predict the remaining life of the equipment.It also provides a theoretical basis to further improve the maintenance and management for ZPW-2000A track circuit. 展开更多
关键词 track circuit health state assessment life prediction support vector data description(SVDD) gray prediction
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Data Transformation for Super-totalstation Positioning System Integrated by GPS and Totalstation 被引量:2
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作者 GUO Jiming ZHANG Zhenglu LUO Nianxue HUANG Quanyi 《Geo-Spatial Information Science》 2003年第1期38-42,共5页
This paper focuses on the integration and data transformation between GPS and totalstation.It emphasizes on the way to transfer the WGS84 Cartesian coordinates to the local two_dimensional plane coordinates and the or... This paper focuses on the integration and data transformation between GPS and totalstation.It emphasizes on the way to transfer the WGS84 Cartesian coordinates to the local two_dimensional plane coordinates and the orthometric height GPS receiver,totalstation,radio,notebook computer and the corresponding software work together to form a new surveying system,the super_totalstation positioning system(SPS) and a new surveying model for terrestrial surveying.With the help of this system,the positions of detail points can be measured. 展开更多
关键词 GPS TPS SPS data transformation
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Quality Assessment of Attribute Data in GIS Based on Simple Random Sampling 被引量:1
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作者 LIU Chun SHI Wenzhong LIU Dajie LIU Chun, Ph. D, postdoctoral fellow, Department of Surveying and Geo-informatics, Tongji University, 1239 Siping Road, Shanghai 200092, China. 《Geo-Spatial Information Science》 2003年第2期13-19,共7页
On the basis of the principles of simple random sampling, the statistical model of rate of disfigurement (RD) is put forward and described in detail. According to the definition of simple random sampling for the attri... On the basis of the principles of simple random sampling, the statistical model of rate of disfigurement (RD) is put forward and described in detail. According to the definition of simple random sampling for the attribute data in GIS, the mean and variance of the RD are deduced as the characteristic value of the statistical model in order to explain the feasibility of the accuracy measurement of the attribute data in GIS by using the RD. Moreover, on the basis of the mean and variance of the RD, the quality assessment method for attribute data of vector maps during the data collecting is discussed. The RD spread graph is also drawn to see whether the quality of the attribute data is under control. The RD model can synthetically judge the quality of attribute data, which is different from other measurement coefficients that only discuss accuracy of classification. 展开更多
关键词 quality assessment simple random sampling rate of disfigurement attributedata
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Understanding the YouTube Partners and Their Data: Measurement and Analysis 被引量:2
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作者 CHENG Xu Fatourechi Mehrdad +2 位作者 MA Xiaoqiang ZHANG Cong LIU Jiangchuan 《China Communications》 SCIE CSCD 2014年第12期26-34,共9页
User generated content,e.g.,from YouTube,the most popular online video sharing site,is one of the major sources of today's big data and it is crucial to understand their inherent characteristics.Recently,YouTube h... User generated content,e.g.,from YouTube,the most popular online video sharing site,is one of the major sources of today's big data and it is crucial to understand their inherent characteristics.Recently,YouTube has started working with content providers(known as YouTube partners) to promote the users' watching and sharing activities.The substantial benefit is to further augment its service and monetize more videos,which is crucial to both YouTube and its partners,as well as to other providers of relevant services.In this paper,our main contribution is to analyze the massive amounts of video data from a YouTube partner's view.We make effective use of Insight,a new analytics service of YouTube that offers simple data analysis for partners.To provide the practical guidance from the raw Insight data,we enable more complex investigations for the inherent features that affect the popularity of the videos.Our findings facilitate YouTube partners to re-design current video publishing strategies,having more opportunities to attract more views. 展开更多
关键词 YouTube partners video popularity viewing behaviour user engagement
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