The influence of an acoustic logging tool on borehole guided wave propagation should be considered in the processing and inversion of the guided waves for formation acoustic property estimation. This study introduces ...The influence of an acoustic logging tool on borehole guided wave propagation should be considered in the processing and inversion of the guided waves for formation acoustic property estimation. This study introduces an equivalent-tool theory that models the tool response using an elastic rod with an effective modulus and applies the theory to multipole acoustic logging for both wireline and logging while drilling (LWD) conditions. The theory can be derived by matching the tool’s acoustic impedance/conductance to that of the multipole acoustic wavefield around the tool, assuming that tool radius is small compared to wavelength. We have validated the effectiveness and accuracy of the theory using numerical modeling and its practicality using field data. In field data applications, one can calibrate the tool parameters by fitting the theoretical dispersion curve to field data without having to consider the actual tool’s structure and composition. We use a dispersion correction example to demonstrate an application of the simple theory to field data processing and the validity of the processing result.展开更多
By the aid of the international mining software SURPAC, a geologic database for a multi-metal mine was established, 3D models of the surface, geologic fault, ore body, cavity and the underground openings were built, a...By the aid of the international mining software SURPAC, a geologic database for a multi-metal mine was established, 3D models of the surface, geologic fault, ore body, cavity and the underground openings were built, and the volume of the cavity of the mine based on the cavity 3D model was calculated. In order to compute the reserves, a grade block model was built and each metal element grade was estimated using Ordinary Kriging. Then, the reserve of each metal element and every sublevel of the mine was worked out. Finally, the calculated result of each metal reserve to its actual prospecting reserve was compared, and the results show that they are all almost equal to each other. The absolute errors of Sn, Pb, and Zn reserves are only 1.45%, 1.59% and 1.62%, respectively. Obviously, the built models are reliable and the calculated results of reserves are correct. They can be used to assist the geologic and mining engineers of the mine to do research work of reserves estimation, mining design, plan making and so on.展开更多
First arrival travel time tomography has achieved wide application. However, tomographic resolution is insufficient because geometry constraints cause rays to be unevenly distributed in the velocity model. The variabl...First arrival travel time tomography has achieved wide application. However, tomographic resolution is insufficient because geometry constraints cause rays to be unevenly distributed in the velocity model. The variable damping constraint method adopts uneven priori information to match uneven data distribution which can lessen the correlation between velocity correction values and ray coverage density. In this paper, we combine the variable damping constraint with a smoothness constraint which is added into the regularization equations in velocity inversion to avoid instability caused by only using the variable damping constraint method. The alpha-trimmed-mean filter is used to smooth and denoise intermediate results in the velocity inversion process. We use the LSQR algorithm to enhance the convergence rate and suppress error propagation in solving linear equations. In this paper, we apply the proposed tomographic method to perform velocity inversion using VSP data. The application in recovery test of the checkerboard model and velocity inversion of real VSP data show that the variable damping constraint method can improve tomographic quality because it can solve the effects of uneven ray coverage. In addition, the examples show that the tomographic result near geophones is much more reliable than other areas in the velocity model.展开更多
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
BIM (building information modelling) has gained wider acceptance in the A/E/C (architecture/engineering/construction) industry in the US and internationally. This paper presents current industry approaches of impl...BIM (building information modelling) has gained wider acceptance in the A/E/C (architecture/engineering/construction) industry in the US and internationally. This paper presents current industry approaches of implementing 3D point cloud data in BIM and VDC (virtual design and construction) applications during various stages of a project life cycle and the challenges associated with processing the huge amount of 3D point cloud data. Conversion from discrete 3D point cloud raster data to geometric/vector BIM data remains to be a labor-intensive process. The needs for intelligent geometric feature detection/reconstruction algorithms for automated point cloud processing and issues related to data management are discussed. This paper also presents an innovative approach for integrating 3D point cloud data with BIM to efficiently augment built environment design, construction and management.展开更多
The article deals with the methodology of pseudorandom data analysis. As a mathematical tool for carrying out the research the extreme value theory was used that creates one of the directions in mathematical statistic...The article deals with the methodology of pseudorandom data analysis. As a mathematical tool for carrying out the research the extreme value theory was used that creates one of the directions in mathematical statistics, and is related to investigating the extreme deviations from the median values in probability distributions. Also, the methods for estimating unknown parameters and algorithm of random-number generation are discussed. The models of treatment the extreme values are constructed which are based on machine generated sample and approach is proposed for their future application for constructing forecasting models.展开更多
In this paper, we research the probability theory and matrix transformation based technique to manage the data for processing and analysis. Clustering analysis research has a long history, over the decades, the import...In this paper, we research the probability theory and matrix transformation based technique to manage the data for processing and analysis. Clustering analysis research has a long history, over the decades, the importance and the cross characteristics with other research direction to get the affirmation of the people. The probability theory and linear algebra act as the powerful tool for analyzing and mining data. The experimental result illustrates the effectiveness. In the near future, we plan to conduct more theoretical analysis on the topic.展开更多
This paper proposes a method of small reservoir flood detention modeling that utilizes data from the American land resources satellite Landsat TM/ETM+. Precipitation and potential evapotranspiration are taken as the c...This paper proposes a method of small reservoir flood detention modeling that utilizes data from the American land resources satellite Landsat TM/ETM+. Precipitation and potential evapotranspiration are taken as the control conditions in this method on the basis of basin terrain classification. The objective of this method is to solve the question of a small-scale water conservancy project’s influence on flood forecasting precision, which can be used in the basin with multitudinous small reservoirs in the upstream region and can help estimate non-runoff data for small reservoir runoff. Taking the 20060826 flood as an example, the flood detention quantity of 19 small reservoirs is modeled. The results show that the absolute error of the total flood detention quantity is 0.2×10 4 m 3 , and the relative error is 0.12%. The flood detention quantity of small reservoirs in the entire basin is then modeled using this method, and the primary flood forecasting model is adjusted. After adjustment, the precision is significantly improved, with the relative error decreasing from 31.8% to 10.1%.展开更多
Geographic Hypermedia(GH)is a rich and interactive map document with geo-tagged graphics,sound and video ele-ments.A Geographic Hypermedia System(GHS)is designed to manage,query,display and explore GH resources.Recogn...Geographic Hypermedia(GH)is a rich and interactive map document with geo-tagged graphics,sound and video ele-ments.A Geographic Hypermedia System(GHS)is designed to manage,query,display and explore GH resources.Recognizing emerging geo-tagged videos and measurable images as valuable geographic data resources,this paper aims to design a web-based GHS using web mapping,geoprocessing,video streaming and XMLHTTP services.The concept,data model,system design and implementation of this GHS are discussed in detail.Geo-tagged videos are modeled as temporal,spatial and metadata entities such as video clip,video path and frame-based descriptions.Similarly,geo-tagged stereo video and derived data are modeled as interre-lated entities:original video,rectified video,stereo video,video path,frame-based description and measurable image(rectified and disparity image with baseline,interior and exterior parameters).The entity data are organized into video files,GIS layers with linear referencing and XML documents for web publishing.These data can be integrated in HTML pages or used as Rich Internet Appli-cations(RIA)using standard web technologies such as the AJAX,ASP.NET and RIA frameworks.An SOA-based GHS is designed using four types of web services:ArcGIS Server 9.3 web mapping and geoprocessing services,Flash FMS 3.0 video streaming ser-vices and GeoRSS XMLHTTP services.GHS applications in road facility management and campus hypermapping indicate that the GH data models and technical solutions introduced in this paper are useful and flexible enough for wider deployment as a GHS.展开更多
This paper proposes a new weighted quantile regression model for longitudinal data with weights chosen by empirical likelihood(EL). This approach efficiently incorporates the information from the conditional quantile ...This paper proposes a new weighted quantile regression model for longitudinal data with weights chosen by empirical likelihood(EL). This approach efficiently incorporates the information from the conditional quantile restrictions to account for within-subject correlations. The resulted estimate is computationally simple and has good performance under modest or high within-subject correlation. The efficiency gain is quantified theoretically and illustrated via simulation and a real data application.展开更多
基金supported by the Fundamental Research Funds for the Central Universities and the National Hi-tech Research and Development Program of China (863 Program) (Grant No. 2007AA06Z232 )
文摘The influence of an acoustic logging tool on borehole guided wave propagation should be considered in the processing and inversion of the guided waves for formation acoustic property estimation. This study introduces an equivalent-tool theory that models the tool response using an elastic rod with an effective modulus and applies the theory to multipole acoustic logging for both wireline and logging while drilling (LWD) conditions. The theory can be derived by matching the tool’s acoustic impedance/conductance to that of the multipole acoustic wavefield around the tool, assuming that tool radius is small compared to wavelength. We have validated the effectiveness and accuracy of the theory using numerical modeling and its practicality using field data. In field data applications, one can calibrate the tool parameters by fitting the theoretical dispersion curve to field data without having to consider the actual tool’s structure and composition. We use a dispersion correction example to demonstrate an application of the simple theory to field data processing and the validity of the processing result.
基金Project(50490274) supported by the National Natural Science Foundation of China
文摘By the aid of the international mining software SURPAC, a geologic database for a multi-metal mine was established, 3D models of the surface, geologic fault, ore body, cavity and the underground openings were built, and the volume of the cavity of the mine based on the cavity 3D model was calculated. In order to compute the reserves, a grade block model was built and each metal element grade was estimated using Ordinary Kriging. Then, the reserve of each metal element and every sublevel of the mine was worked out. Finally, the calculated result of each metal reserve to its actual prospecting reserve was compared, and the results show that they are all almost equal to each other. The absolute errors of Sn, Pb, and Zn reserves are only 1.45%, 1.59% and 1.62%, respectively. Obviously, the built models are reliable and the calculated results of reserves are correct. They can be used to assist the geologic and mining engineers of the mine to do research work of reserves estimation, mining design, plan making and so on.
基金supported by the China Important National Science and Technology Specific Projects (No2011ZX05024-001-02)
文摘First arrival travel time tomography has achieved wide application. However, tomographic resolution is insufficient because geometry constraints cause rays to be unevenly distributed in the velocity model. The variable damping constraint method adopts uneven priori information to match uneven data distribution which can lessen the correlation between velocity correction values and ray coverage density. In this paper, we combine the variable damping constraint with a smoothness constraint which is added into the regularization equations in velocity inversion to avoid instability caused by only using the variable damping constraint method. The alpha-trimmed-mean filter is used to smooth and denoise intermediate results in the velocity inversion process. We use the LSQR algorithm to enhance the convergence rate and suppress error propagation in solving linear equations. In this paper, we apply the proposed tomographic method to perform velocity inversion using VSP data. The application in recovery test of the checkerboard model and velocity inversion of real VSP data show that the variable damping constraint method can improve tomographic quality because it can solve the effects of uneven ray coverage. In addition, the examples show that the tomographic result near geophones is much more reliable than other areas in the velocity model.
基金sponsored by National Natural Science Fund Projects (No.41204072 and No.U1262208)Research Funds Provided to New Recruitments of China University of Petroleum-Beijing (YJRC-2011-03)Science Foundation of China University of Petroleum-Beijing (YJRC-2013-36)
文摘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.
文摘BIM (building information modelling) has gained wider acceptance in the A/E/C (architecture/engineering/construction) industry in the US and internationally. This paper presents current industry approaches of implementing 3D point cloud data in BIM and VDC (virtual design and construction) applications during various stages of a project life cycle and the challenges associated with processing the huge amount of 3D point cloud data. Conversion from discrete 3D point cloud raster data to geometric/vector BIM data remains to be a labor-intensive process. The needs for intelligent geometric feature detection/reconstruction algorithms for automated point cloud processing and issues related to data management are discussed. This paper also presents an innovative approach for integrating 3D point cloud data with BIM to efficiently augment built environment design, construction and management.
文摘The article deals with the methodology of pseudorandom data analysis. As a mathematical tool for carrying out the research the extreme value theory was used that creates one of the directions in mathematical statistics, and is related to investigating the extreme deviations from the median values in probability distributions. Also, the methods for estimating unknown parameters and algorithm of random-number generation are discussed. The models of treatment the extreme values are constructed which are based on machine generated sample and approach is proposed for their future application for constructing forecasting models.
文摘In this paper, we research the probability theory and matrix transformation based technique to manage the data for processing and analysis. Clustering analysis research has a long history, over the decades, the importance and the cross characteristics with other research direction to get the affirmation of the people. The probability theory and linear algebra act as the powerful tool for analyzing and mining data. The experimental result illustrates the effectiveness. In the near future, we plan to conduct more theoretical analysis on the topic.
基金supported by the National Natural Science Foundation of China (Grant Nos. 50809010, 50909012, 51079014)the National Key Technology R&D Program during the 11th Five-Year Plan Period of China (Grant No. 2007BAB28B01)
文摘This paper proposes a method of small reservoir flood detention modeling that utilizes data from the American land resources satellite Landsat TM/ETM+. Precipitation and potential evapotranspiration are taken as the control conditions in this method on the basis of basin terrain classification. The objective of this method is to solve the question of a small-scale water conservancy project’s influence on flood forecasting precision, which can be used in the basin with multitudinous small reservoirs in the upstream region and can help estimate non-runoff data for small reservoir runoff. Taking the 20060826 flood as an example, the flood detention quantity of 19 small reservoirs is modeled. The results show that the absolute error of the total flood detention quantity is 0.2×10 4 m 3 , and the relative error is 0.12%. The flood detention quantity of small reservoirs in the entire basin is then modeled using this method, and the primary flood forecasting model is adjusted. After adjustment, the precision is significantly improved, with the relative error decreasing from 31.8% to 10.1%.
基金Supported by the National Natural Science Foundation of China (No.40771166 )the Henan University Foundation (No.SBGJ090605)
文摘Geographic Hypermedia(GH)is a rich and interactive map document with geo-tagged graphics,sound and video ele-ments.A Geographic Hypermedia System(GHS)is designed to manage,query,display and explore GH resources.Recognizing emerging geo-tagged videos and measurable images as valuable geographic data resources,this paper aims to design a web-based GHS using web mapping,geoprocessing,video streaming and XMLHTTP services.The concept,data model,system design and implementation of this GHS are discussed in detail.Geo-tagged videos are modeled as temporal,spatial and metadata entities such as video clip,video path and frame-based descriptions.Similarly,geo-tagged stereo video and derived data are modeled as interre-lated entities:original video,rectified video,stereo video,video path,frame-based description and measurable image(rectified and disparity image with baseline,interior and exterior parameters).The entity data are organized into video files,GIS layers with linear referencing and XML documents for web publishing.These data can be integrated in HTML pages or used as Rich Internet Appli-cations(RIA)using standard web technologies such as the AJAX,ASP.NET and RIA frameworks.An SOA-based GHS is designed using four types of web services:ArcGIS Server 9.3 web mapping and geoprocessing services,Flash FMS 3.0 video streaming ser-vices and GeoRSS XMLHTTP services.GHS applications in road facility management and campus hypermapping indicate that the GH data models and technical solutions introduced in this paper are useful and flexible enough for wider deployment as a GHS.
基金supported by National Natural Science Foundation of China (Grant Nos. 11401048, 11301037, 11571051 and 11201174)the Natural Science Foundation for Young Scientists of Jilin Province of China (Grant Nos. 20150520055JH and 20150520054JH)
文摘This paper proposes a new weighted quantile regression model for longitudinal data with weights chosen by empirical likelihood(EL). This approach efficiently incorporates the information from the conditional quantile restrictions to account for within-subject correlations. The resulted estimate is computationally simple and has good performance under modest or high within-subject correlation. The efficiency gain is quantified theoretically and illustrated via simulation and a real data application.