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Application of Artificial Neural Network for Height Modelling

Omer Hassan
2015 International Journal on Recent and Innovation Trends in Computing and Communication  
The objective of this research is to test the possibility of using artificial neural networks method for height modelling in different topographic areas, and assessing its resultant precision in comparison  ...  If a datum surface is defined for the observed points, the heights of these points (reduced levels) can be computed. In ordinary orthometric levelling Geoid surface is usually used as a datum.  ...  Digital Height Model (DHM), Digital Ground Model (DGM), and Digital Terrain Elevation Model (DTEM) are all common terms.  ... 
doi:10.17762/ijritcc2321-8169.1503103 fatcat:syduca5mrjd67eh6izxf75dyh4

Accuracy Assessment of Digital Elevation Models based on Approximation Theory

Peng Hu, Xiaohang Liu, Hai Hu
2009 Photogrammetric Engineering and Remote Sensing  
Introduction Digital elevation models (DEM) are essential to various applications such as terrain modeling and watershed delineation.  ...  Equation 1 shows that the total error in a DEM point is not random but a mixture of random and systematic error.  ...  His research has focused on digital elevation model generation and accuracy assessment and computational geometry.  ... 
doi:10.14358/pers.75.1.49 fatcat:zs3id6siy5aoflkxuvvly2bioe

Study of the TIN Gross Error Detection based on Terrain Inclination

Sheng Qinghong
2011 Journal of clean energy technologies  
errors, and points out that gross errors and random errors are made in the process of image matching and orientation.  ...  can eliminate serious distortions of contours in points of gross errors.  ...  Compared with the random error, the gross error produced by the mismatching of image in image correlation distorts the space variation reflected by digital elevation model more seriously.  ... 
doi:10.7763/ijcte.2011.v3.325 fatcat:rsogthalkfesdeloc77nd5z2dm

Digital elevation model uncertainty and hazard analysis using a geophysical flow model

E. R. Stefanescu, M. Bursik, G. Cordoba, K. Dalbey, M. D. Jones, A. K. Patra, D. C. Pieri, E. B. Pitman, M. F. Sheridan
2012 Proceedings of the Royal Society A  
This paper describes a new methodology to quantify the variation in the output of a computational fluid dynamics model for block and ash flows, when the digital elevation model (DEM) of the terrain and  ...  This paper extends this approach to include the effect of terrain error and uncertainty. The results are based on potential flows at Mammoth Mountain, CA, and Galeras Volcano, Colombia.  ...  The work and opinions expressed herein are those of the authors alone and do not reflect the opinion of NASA. We are grateful to JPL for the construction and distribution of the TOPSAR dataset.  ... 
doi:10.1098/rspa.2011.0711 fatcat:tpfksn274ne4bapxrff3gzhyjy

Digital terrain model height estimation using support vector machine regression
English

Onuwa Okwuashi, Christopher Ndehedehe
2015 South African Journal of Science  
The high accuracy furnished by SVMR in this experiment attests that SVMR is a promising model for digital terrain model interpolation.  ...  Digital terrain model interpolation is intrinsically a surface fitting problem, in which unknown heights H are estimated from known X-Y coordinates.  ...  The box plot in Figure 10a shows Research Article Digital terrain model height estimation error was -0.09.  ... 
doi:10.17159/sajs.2015/20140153 fatcat:tzbgzcig2rag3po2vpwq4zezru

Quality Assessments of Seafloor Mapping with Multibeam Echo Sounders [chapter]

Jan Terje, Stein Nilse
2011 Applications and Experiences of Quality Control  
Computation of random measurement errors Random measurement errors in multibeam echo sounder data are functions of the kind of measurement equipment used; the sea depth, the terrain slope and the weather  ...  These methods can be used to compute digital terrain models with regular sampling patterns from scattered data.  ...  The following example will clarify the role The rich palette of topics set out in this book provides a sufficiently broad overview of the developments in the field of quality control.  ... 
doi:10.5772/15668 fatcat:xl3m73b5szei7geli47skhjbqm

Page 337 of American Society of Civil Engineers. Collected Journals Vol. 119, Issue 3 [page]

1993 American Society of Civil Engineers. Collected Journals  
“The prediction of hillslope flow paths for distributed hydrological modelling using digital terrain models.” Int. J. Hydrological Process, 5(1), 59-79. Saupe, D. (1988).  ...  “Digital terrain modelling: a review of hydrological, geomorphological and biological applications.” Int. J. of Hydrological Process, 5(1), 3-30. Morris, E. M., and Woolhiser, D. A. (1980).  ... 

Uncertainties associated with digital elevation models for hydrologic applications: a review

S. P. Wechsler
2007 Hydrology and Earth System Sciences  
A considerable amount of research has been conducted to address uncertainty associated with error in digital elevation models (DEMs) and the 5 propagation of error to derived terrain parameters.  ...  .: Digital Elevation Model Networks (DEMON): A model of flow over hillslopes for computation of contributing and dispersal areas, Water Resour. Res., 5 30(6), 681-1692, 1994.  ...  ., and Rodriguez-Iturbe: On the extraction of channel networks from digital elevation data, in: Terrain Analysis and Distributed Modeling In Hydrology, edited by: Beven, K. and Moore, I.  ... 
doi:10.5194/hess-11-1481-2007 fatcat:w4ud7gtt7nd5ziyzz4es4uyq5i

Uncertainties associated with digital elevation models for hydrologic applications: a review

S. Wechsler
2006 Hydrology and Earth System Sciences Discussions  
A considerable amount of research has been conducted to address uncertainty associated with error in digital elevation models (DEMs) and the 5 propagation of error to derived terrain parameters.  ...  .: Digital Elevation Model Networks (DEMON): A model of flow over hillslopes for computation of contributing and dispersal areas, Water Resour. Res., 5 30(6), 681-1692, 1994.  ...  ., and Rodriguez-Iturbe: On the extraction of channel networks from digital elevation data, in: Terrain Analysis and Distributed Modeling In Hydrology, edited by: Beven, K. and Moore, I.  ... 
doi:10.5194/hessd-3-2343-2006 fatcat:fbaxlxht7jaczazen765sqzosy

Flight test of radar altimeter enhancement for terrain-referenced guidance

Richard E. Zelenka, Zee Yee, Andre Zirkler
1995 Journal of Guidance Control and Dynamics  
The bias of the radar altimeter measurement is reflected in the random- walk model. Similar models for terrain-referenced altitude errors have been employed in the literature.  ...  The first state is modeled as a random walk: x) = wy (3) where w, is a Gaussian zero-mean white noise with variance ao? of 20°ft?/s.  ... 
doi:10.2514/3.21450 fatcat:uxvbysutqfbeha2fxsv3cldzwy

Modelling vertical error in LiDAR-derived digital elevation models

Fernando J. Aguilar, Jon P. Mills, Jorge Delgado, Manuel A. Aguilar, J.G. Negreiros, José L. Pérez
2010 ISPRS journal of photogrammetry and remote sensing (Print)  
A hybrid theoretical-empirical model has been developed for modelling the error in LiDAR-derived digital elevation models (DEMs) of non-open terrain.  ...  The theoretical component seeks to model the propagation of the sample data error (SDE), i.e. the error from light detection and ranging (LiDAR) data capture of ground sampled points in open terrain, towards  ...  Elements of this research have been made possible through the project entitled ''Integration and exploratory analysis of multisource geospatial data for monitoring and modelling the evolution and vulnerability  ... 
doi:10.1016/j.isprsjprs.2009.09.003 fatcat:zuwufjphxbgq7kgvvsbriqdr3q

The Stability of The Longley-Rice Irregular Terrain Model for Typical Problems [article]

Caleb Phillips, Douglas Sicker, Dirk Grunwald
2011 arXiv   pre-print
In this paper, we analyze the numerical stability of the popular Longley-Rice Irregular Terrain Model (ITM).  ...  This model is widely used to plan wireless networks and in simulation-validated research and hence its stability is of fundamental importance to the correctness of a large amount of work.  ...  This result provides confidence in the stability of the output of the ITM model as well as other similar models that compute diffraction over terrain (e.g, [3, 11] Although it may be possible to automate  ... 
arXiv:1109.1843v1 fatcat:yh265u7ycramfo3wywlenm3ssa

ANALYSIS AND VALIDATION OF GRID DEM GENERATION BASED ON GAUSSIAN MARKOV RANDOM FIELD

F. J. Aguilar, M. A. Aguilar, J. L. Blanco, A. Nemmaoui, A. M. García Lorca
2016 The International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences  
In every case, the remaining points (scattered observed points) were used to obtain a 1 m grid spacing GMRF-interpolated Digital Surface Model (DSM) whose accuracy was assessed by means of the set of previously  ...  Finally, the GMRF method was applied to a real-world case consisting of filling the LiDAR-derived DSM gaps after manually filtering out non-ground points to obtain a Digital Terrain Model (DTM).  ...  It was also supported by the National R+D+i Plan Project DPI2014-56364-C2-1-R of the Spanish Ministry of Economy and Competitiveness and ERDF funds.  ... 
doi:10.5194/isprs-archives-xli-b2-277-2016 fatcat:ton2rnsv3namhpbb2np652kciy

The ConMap approach for terrain-based digital soil mapping

T. Behrens, K. Schmidt, A. X. Zhu, T. Scholten
2010 European Journal of Soil Science  
These differences are used as features in random forest regressions.  ...  Crossvalidation root mean square error (RMSE) decreased from 16.1 when the standard digital terrain analysis was used to 11.2 when ConMap was used.  ...  Acknowledgements We are grateful to the Federal Geological Surveys of Rhineland-Palatinate and Hesse for providing the data.  ... 
doi:10.1111/j.1365-2389.2009.01205.x fatcat:xk5m3xyn6nen5ptbdrxybc44ya

A Comparative Study of Digital Terrain Data for Visibility Analysis in the Planning and Management of Scenic Resources

Toru Otawa
2015 Journal of Geodesy and Geomatics Engineering  
A DEM (digital elevation model) was once used to calculate viewsheds in the early days of GIS applications.  ...  Using digital terrain data acquired for part of the Nez Perce National Forest in Idaho, calculation accuracy for viewsheds was scrutinized in depth.  ...  Acknowledgments Many thanks go to the Forest Sciences Laboratory of the US Forest Service Rocky Mountain Research Station located in Moscow, Idaho, USA for providing this researcher with a set of LiDAR  ... 
doi:10.17265/2332-8223/2015.04.001 fatcat:oupkvb237ncljlru4npgpph3de
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