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The Zones Algorithm for Finding Points-Near-a-Point or Cross-Matching Spatial Datasets [article]

Jim Gray, Maria A. Nieto-Santisteban, Alexander S. Szalay
2007 arXiv   pre-print
Hence, the Zones Algorithm gives a portable-relational implementation of points-near-point, spatial cross-match, and self-match queries.  ...  Zones index an N-dimensional Euclidian or metric space to efficiently support points-near-a-point queries either within a dataset or between two datasets.  ...  distance test Cross-Match and Self-Match Applications often want to find, for all objects, all neighbors within a certain radius -called a self-match of one dataset is compared with itself or a cross-match  ... 
arXiv:cs/0701171v1 fatcat:ov46ppi7dbhydaxq6s63ypm6dy

Large Catalogue Query Performance in Relational Databases

Robert A. Power
2007 Publications Astronomical Society of Australia  
The queries tested are those expected from the astronomy community: general database queries, cone searches, neighbour finding and cross matching.  ...  Neighbour finding and cross matching are not well supported in a database environment when compared to software specifically developed to solve these problems.  ...  Thanks also to CSIRO staff Dave Abel, Drew Devereux and Peter Lamb for the original work on neighbour finding and cross matching.  ... 
doi:10.1071/as06026 fatcat:y2zi2ma3zvh55ciz7f7gwjrya4


A. W. Lyda, X. Zhang, C. L. Glennie, K. Hudnut, B. A. Brooks
2016 The International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences  
Surveys taken before and after an earthquake for example, can provide decimeter-level, 3D near-field estimates of land deformation that offer better spatial coverage of the near field rupture zone than  ...  Adapted here for an earthquake with little vertical movement, the 3D point cloud is interpolated into a 2D DTM image and horizontal deformation is determined by assessing the cross-correlation of interrogation  ...  ACKNOWLEDGEMENTS Partial support for the analysis of displacement was provided by the USGS through a cooperative agreement with the University of Houston.  ... 
doi:10.5194/isprs-archives-xli-b2-35-2016 fatcat:dvus7qxfonaall6kmpflloju6m

Point-tracked quantitative analysis of left ventricular surface motion from 3-D image sequences

Pengcheng Shi, A.J. Sinusas, R.T. Constable, E. Ritman, J.S. Duncan
2000 IEEE Transactions on Medical Imaging  
The non-invasive, algorithm-derived results are validated in two levels: the motion trajectories are compared to those of implanted imaging-opaque markers of a canine model in two imaging modalities, where  ...  The first one attempts to measure wall motion by detecting gray level changes over time for each pixel, the optical flow strategy [31, 56, 60] .  ...  The reason to use this sparse set of points for initial match is to avoid cross-over between nearby matches.  ... 
doi:10.1109/42.832958 pmid:10782617 fatcat:tv2inlldbbhephiz2uywuy65oi

Enhancement of Digital Map using High Resolution Images

G Karthik
Iterative Relaxation Algorithm (IRA) is especially used point matching based at the comparative distance records in among the points.  ...  The Vector Road Intersections that is coordinated to removed factor sets by way of a Relaxation-Labeling Algorithm.  ...  The intersection points from both map will be matched by using point matching algorithm. Then the matched point pairs will act as a control point to perform local affine transformation.  ... 
doi:10.26782/jmcms.spl.2019.08.00042 fatcat:ngwdsn7ngbg5roesyfi3cyfioy

Continuous Coastal Monitoring with an Automated Terrestrial Lidar Scanner

Annika O'Dea, Katherine L. Brodie, Preston Hartzell
2019 Journal of Marine Science and Engineering  
This paper details the collection, geo-referencing, and data processing algorithms for a fully-automated, permanently deployed terrestrial lidar system for coastal monitoring.  ...  The data are geo-referenced each hour using a rigorous co-registration process that fits 11 fixed planes to a baseline scan to account for small platform movements, and the residual errors from the fit  ...  The funders had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript, or in the decision to publish the results.  ... 
doi:10.3390/jmse7020037 fatcat:ol3fc5dqhnf3hdrwlzmq5bupva

ASTROIDE: A Unified Astronomical Big Data Processing Engine over Spark

Mariem BRAHEM, Karine Zeitouni, Laurent Yeh
2018 IEEE Transactions on Big Data  
Recognizing the need to better handle astronomical datasets, we designed ASTROIDE, a distributed data server for astronomical data.  ...  ASTROIDE offers a simple, expressive and unified interface through ADQL, a standard language for querying databases in astronomy.  ...  ACKNOWLEDGMENTS The present paper has been partially supported by Centre National d'Etudes Spatiales (CNES) and by the MASTER project that has received funding from the European Union's Horizon 2020 research  ... 
doi:10.1109/tbdata.2018.2873749 fatcat:vda3gtes45g7bgm53kc33kzm3m

Cross-Matching Multiple Spatial Observations and Dealing with Missing Data [article]

Jim Gray, Alex Szalay, Tamas Budavari, Robert Lupton, Maria Nieto-Santisteban, Ani Thakar
2007 arXiv   pre-print
Cross-match spatially clusters and organizes several astronomical point-source measurements from one or more surveys. Ideally, each object would be found in each survey.  ...  Cross-Matching Multiple Spatial Observations and Dealing with Missing Data.  ...  Given a point in one run, the probability in finding another point at a separation r in another run, given perfect accuracy is the sum of a Dirac delta for the object plus the contribution from a spatial  ... 
arXiv:cs/0701172v1 fatcat:kni3imhmlfaezh7rpo4gruswgm

Improving the Accuracy of Remote Sensing Land Cover Classification by GEO-ECO Zoning Coupled with Geostatistical Simulation

Ling Zhu, Jing Li, Yixuan La, Tao Jia
2021 Applied Sciences  
The pre-classified image that needs to be improved and Geo-Eco zoning attribute data are used as auxiliary data for co-simulation.  ...  In this study, a method is presented to evaluate and improve the accuracy of land cover classification products by coupling Geo-Eco zoning and Markov chain geoscience statistical simulation.  ...  Acknowledgments: The authors gratefully acknowledge the support of NGCC (National Geomatics Center of China). Conflicts of Interest: The authors declare no conflict of interest.  ... 
doi:10.3390/app11020553 fatcat:ypc5zhdaafgjjpuhjnc2solyyu

Efficient Stereo with Accurate 3-D Boundaries

M. Sizintsev, R. Wildes
2006 Procedings of the British Machine Vision Conference 2006  
Second, a novel formulation of half-occlusion cues within the coarse-to-fine, block matching framework is described to inhibit false matches that can arise in regions near occlusions.  ...  This paper presents methods for recovering accurate binocular disparity estimates in the vicinity of 3D surface discontinuities.  ...  For local methods, the use of adaptive spatial support for match windows can ameliorate issues arising in attempts to match near 3D discontinuities by shaping windows to avoid poorly defined matches [  ... 
doi:10.5244/c.20.25 dblp:conf/bmvc/SizintsevW06 fatcat:n4zah2ucsjfppkadvekqoexmoe

3D Global Localization in the Underground Mine Environment Using Mobile LiDAR Mapping and Point Cloud Registration

Jieun Baek, Junhyeok Park, Seongjun Cho, Changwon Lee
2022 Sensors  
The local point cloud dataset formed for the six areas of the underground mine precisely matched the global point cloud, with a low average error of approximately 0.13 m, regardless of the type of mobile  ...  An initial global point cloud map was built for an entire underground mine area using mobile LiDAR; a local LiDAR scan (local point cloud) was generated at the point where underground positioning was required  ...  The 6th level drift is divided into two zones (A and B) due to the ore body distribution. Local point cloud datasets were generated for the zone B.  ... 
doi:10.3390/s22082873 pmid:35458856 pmcid:PMC9029966 fatcat:eiey436dtna2xpzghxhkwxaeaq


2015 Services Transactions on Cloud Computing  
Via mobility localization formalism, we demonstrate that an implementation of our geo-spatial partition algorithms could balance workload and minimize cross-node communication.  ...  By taking the spatial connectivity implied by trajectory streams into consideration, a trajectory preserving partitioning method is proposed for improving the quality of geo-partitioning.  ...  Then the traversed lines form a polygon as the border of a buffer zone. For finding the separating polylines to maximize the margin in the buffer zone, a triangulated approach is implemented.  ... 
doi:10.29268/stcc.2015.3.1.3 fatcat:pxuechmepfdsjak4e6jsbyj7ge

Three-dimensional surface displacements and rotations from differencing pre- and post-earthquake LiDAR point clouds

Edwin Nissen, Aravindhan K. Krishnan, J. Ramón Arrowsmith, Srikanth Saripalli
2012 Geophysical Research Letters  
Our research was supported through the Southern California Earthquake Center, a grant from the National Science Foundation (EAR-1148302), and a SESE Exploration Fellowship to E. N.  ...  The project was funded by the EAR Geophysics program at the National Science Foundation (NSF) and relied on the generosity of many landowners along the fault zones.  ...  in the near field ($1 km) of the rupture zone.  ... 
doi:10.1029/2012gl052460 fatcat:eutnuhbtenhi3eiansyomtyyz4

Learning-based Regularization for Cardiac Strain Analysis with Ability for Domain Adaptation [article]

Allen Lu, Nripesh Parajuli, Maria Zontak, John Stendahl, Kevinminh Ta, Zhao Liu, Nabil Boutagy, Geng-Shi Jeng, Imran Alkhalil, Lawrence H. Staib, Matthew O'Donnell, Albert J. Sinusas, James S. Duncan
2018 arXiv   pre-print
We extended this framework to include a supervised loss term on synthetic data and showed the effects of biomechanical constraints on the network's ability for domain adaptation.  ...  In this work, we incorporated the notion of domain adaptation into a supervised neural network regularization framework.  ...  ACKNOWLEDGMENT The authors would like to thank the past and current members of Dr. Albert Sinusas' lab group who were involved in the image acquisition process.  ... 
arXiv:1807.04807v1 fatcat:xnruoyjxbncstattgwbbpj76oy

Vegetation Height Estimation Near Power transmission poles Via satellite Stereo Images using 3D Depth Estimation Algorithms

A. Qayyum, A. S. Malik, M. N. M. Saad, M. Iqbal, F. Abdullah, W. Rahseed, T. A. R. B. T. Abdullah, A. Q. Ramli
2015 The International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences  
In this paper, we have proposed a novel approach to monitor the vegetation/trees near or under the power transmission poles using satellite stereo images, which were acquired using Pleiades satellites.  ...  Our dataset covers power transmission poles in a state called Sabah in East Malaysia, encompassing a total of 52 poles in the area of 100 km.  ...  For example, the stereo vision system can determine depth of scene with help of two images, which are captured from the same or vantage points (Ghaffar, 2004) .  ... 
doi:10.5194/isprsarchives-xl-7-w3-489-2015 fatcat:llowbbdntvf5pfseawatzde6i4
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