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Digital terrain modeling

John P. Wilson
2012 Geomorphology  
This equation corrects for elevation via a lapse rate, slope-aspect effects via the short-wave radiation ratio, and vegetation effects via a leaf area index. 1993d).  ...  Primary attributes include slope, aspect, plan and profile curvature, flow-path length, and upslope contributing area (see Table 1 .1 for a more complete list).  ...  tion method that avoids the need for a priori judgments about the terrain/satellite imagery/vegetation relationships.  ... 
doi:10.1016/j.geomorph.2011.03.012 fatcat:32wez6jdanaetbxtw7m4g2mlt4

Characterizing Land Surface Anisotropic Reflectance over Rugged Terrain: A Review of Concepts and Recent Developments

Jianguang Wen, Qiang Liu, Qing Xiao, Qinhuo Liu, Dongqin You, Dalei Hao, Shengbiao Wu, Xingwen Lin
2018 Remote Sensing  
The discussion focuses on land surface reflectance retrieval over mountainous areas, the difference in solo slope and composite slope BRDF models, and suggested future research to improve the accuracy  ...  In this paper, after a brief introduction of the theoretical background of the BRDF over rugged terrain, the status of estimating land surface BRDF properties over rugged terrain is comprehensively reviewed  ...  ROSST is the improved ROSS model for solo slope terrain; PLC is A Physical Solo Slope Canopy Reflectance Model Based On The Path Length Correction; GOMST is the geometric-optical mutual shadowing model  ... 
doi:10.3390/rs10030370 fatcat:ayydrp5kunflfdfka3atsvqwge

Cost-Efficient Global Robot Navigation in Rugged Off-Road Terrain

T. Braun
2011 Künstliche Intelligenz  
, but also cost-efficient, e.g. able to generate navigation paths which optimize a cost measure closely related to terrain traversability.  ...  It would have been much harder to pull through this without you, Chrissy. This thesis has been funded by the PhD program of the Department of Computer Sciences of the University of Kaiserslautern.  ...  A second improvement was put forward to improve the computation speed of the sensor analysis methods.  ... 
doi:10.1007/s13218-011-0088-9 fatcat:u4ssainmcvc3jmqdon6gpjg674

Evaluation of a forest parameterization to improve boundary layer flow simulations over complex terrain. A case study using WRF-LES V4.0.1

Julian Quimbayo-Duarte, Johannes Wagner, Norman Wildmann, Thomas Gerz, Juerg Schmidli
2022 Geoscientific Model Development  
We evaluate the influence of a forest parametrization on the simulation of the boundary layer flow over moderate complex terrain in the context of the Perdigão 2017 field campaign.  ...  The mean diurnal cycle during the IOP shows a significant improvement of the along-valley wind speed and the wind direction when using the forest parametrization.  ...  Many thanks also go to Robert Menke and Jakob Mann from DTU for providing the wind scanner data and to NCAR EOL for the tower data. Financial support.  ... 
doi:10.5194/gmd-15-5195-2022 fatcat:il4ewcrryzdszaks2sife2k6wi

Surface Fluxes and Characteristics of Drying Semi-Arid Terrain in West Africa

D. Schüttemeyer, A. F. Moene, A. A. M. Holtslag, H. A. R. de. Bruin, N. van de. Giesen
2006 Boundary-layer Meteorology  
The observations are conducted with a combined system, consisting of a Large Aperture Scintillometer (LAS) for areally averaged sensible heat flux, radiometers and sensors for soil heat flux.  ...  The measurements of a seasonal cycle in 2002/2003 were gathered including the rapid wet-to-dry transition after the wet season at two locations in Ghana, one in the humid tropical southern region and one  ...  The authors would like to thank Raymond Kasei, Ronald Groen and Gabriel Akotia for assistance in the field and two D.SCHÜTTEMEYER ET AL. anonymous reviewers for their constructive comments on the first  ... 
doi:10.1007/s10546-005-9028-2 fatcat:c4k67ggcefhk7idznn4kgsfqxq

Generating enhanced natural environments and terrain for interactive combat simulations (GENETICS)

William D. Wells
2005 Proceedings of the ACM symposium on Virtual reality software and technology - VRST '05  
Public reporting burden for this collection of information is estimated to average 1 hour per response, including the time for reviewing instruction, searching existing data sources, gathering and maintaining  ...  Send comments regarding this burden estimate or any other aspect of this collection of information, including suggestions for reducing this burden, to Washington headquarters Services, Directorate for  ...  If a reasonable cutting path cannot be obtained (determined by a pixel color error metric over the set of 32 paths for the eight tile set), then a new set of four sample diamonds is selected.  ... 
doi:10.1145/1101616.1101655 dblp:conf/vrst/Wells05 fatcat:7zz2nynrpfchjba27dr7yfmbvu

Ground Reflectance Retrieval on Horizontal and Inclined Terrains Using the Software Package REFLECT

Yacine Bouroubi, Wided Batita, François Cavayas, Nicolas Tremblay
2018 Remote Sensing  
A new approach is proposed for adjacency effect correction. Topographic effects were also taken into account, and a new model was developed for forest canopies.  ...  The computation of atmospheric parameters is based on the 6S (Second Simulation of the Satellite Signal in the Solar Spectrum) routines.  ...  between the ground reflectance of inclined terrains (three slope ranges: 6 • < β < 12 • , 12 • < β < 18 • , and β > 18 • ) and of flat terrains (β < 6 • ) for all of the forested area of the three SPOT  ... 
doi:10.3390/rs10101638 fatcat:hb7rrz6t3jf2bb4opdydk275qa

Evaluation of Two Land Surface Schemes Used in Terrains of Increasing Aridity in West Africa

D. Schüttemeyer, A. F. Moene, A. A. M. Holtslag, H. A. R. de Bruin
2008 Journal of Hydrometeorology  
The models perform poorly in simulating soil heat fluxes with larger errors for TESSEL for both sites.  ...  In this study different parameterizations for land surface models currently employed in meteorological models at ECMWF [Tiled ECMWF Surface Scheme for Exchange Processes over Land (TESSEL)] and NCEP (Noah  ...  area index.  ... 
doi:10.1175/2007jhm797.1 fatcat:kfe4bm4skvcjvg5agcc4uasclq

Using wind fields from a high-resolution atmospheric model for simulating snow dynamics in mountainous terrain

M. Bernhardt, G. Zängl, G. E. Liston, U. Strasser, W. Mauser
2009 Hydrological Processes  
project of the German Ministry for Education and Research (bmb+f).  ...  Das liegt vor allem in der Tatsache begründet, dass die Berechnung von qualitativ hochwertigen Windfeldern in gebirgigem Terrain bis heute nahezu unmöglich ist.  ...  LAI = leaf area index, ρ = vegetation height. Figure 11 : 11 Schematic illustration of the transport model.  ... 
doi:10.1002/hyp.7208 fatcat:jt35b3l3prgktc5bsbh4pmuq34

RETRACTED: An autonomous all terrain robotic system for field demining missions

David Portugal, Gonçalo Cabrita, Bruno D. Gouveia, David C. Santos, José A. Prado
2015 Robotics and Autonomous Systems  
h i g h l i g h t s • Proposal of a new affordable, lightweight and autonomous all-terrain robot for demining operations. • Complete description of the mechanical system and design of the modular robotic  ...  In the scope of the EU FP7 TIRAMISU Project, a toolbox for humanitarian demining missions is being developed by the consortium members.  ...  as terrain traversability analysis.  ... 
doi:10.1016/j.robot.2015.02.013 fatcat:n7baenjcbfcj7eaerqtmatle6a

Evaluation and Intercomparison of Topographic Correction Methods Based on Landsat Images and Simulated Data

Yichuan Ma, Tao He, Ainong Li, Sike Li
2021 Remote Sensing  
We recommend including more simulated images for a more in-depth evaluation.  ...  well as images simulated by a 3D radiative transfer model.  ...  We extend our thanks to Jianbo Qi and Jiang Chen for helping us complete LESS simulation and draw figures, respectively.  ... 
doi:10.3390/rs13204120 fatcat:jwdvciwpx5b5pjixvded3k3yny

Forest ecosystem processes at the watershed scale: incorporating hillslope hydrology

Lawrence E Band, Pitman Patterson, Ramakrishna Nemani, Steven W Running
1993 Agricultural and Forest Meteorology  
For. Meteorol., 63: 93-126. An approach to distributed modeling of watershed hydro-ecological processes over large spatial scales is described.  ...  the parameterization and simulation of a suite of ecological and hydrological flux and storage processes through the watershed.  ...  Lars Pierce, Joseph Coughlan, Jennifer Dungan and David Peterson aided in field data collection, image analysis and data reduction.  ... 
doi:10.1016/0168-1923(93)90024-c fatcat:4bs65ob3xjfunko7uyetj3ov6u

Measurement of Surface Energy Fluxes from Two Rangeland Sites and Comparison with a Multilayer Canopy Model

Gerald N. Flerchinger, Michele L. Reba, Danny Marks
2012 Journal of Hydrometeorology  
The purpose of this study was to evaluate surface energy fluxes measured using three eddy covariance systems above and within two rangeland vegetation sites and use the data to improve simulations of turbulent  ...  Rangelands are often characterized by a patchy mosaic of vegetation types, making measurement and modeling of surface energy fluxes particularly challenging.  ...  or soil surface; V is a function leaf area index: V 5 1 2 exp[2min(L T , L cr )] 1 2 exp(2L cr ) , (8) where L T is total leaf area index and L cr is a critical value assumed for full canopy cover, taken  ... 
doi:10.1175/jhm-d-11-093.1 fatcat:w2cnvol7bzesfas4evdvy6k25m

Surface fluxes and water balance of spatially varying vegetation within a small mountainous headwater catchment

G. N. Flerchinger, D. Marks, M. L. Reba, Q. Yu, M. S. Seyfried
2010 Hydrology and Earth System Sciences  
Peak leaf area index of the sagebrush, aspen, and aspen understory was 0.77, 1.35, and 1.20, respectively.  ...  Missing periods of measured data were common and made it necessary to extrapolate measured fluxes to the missing periods using a combination of measured and simulated data.  ...  Vegetation is approximately 60 cm in height with a leaf area index (LAI) of 0.77 based on point frame measurements. The site is a gently rolling ridge top with slope varying from 1 to 3%.  ... 
doi:10.5194/hess-14-965-2010 fatcat:b363ellhknfcxnyvehzxhp7zxy

Automatic Landform Recognition from the Perspective of Watershed Spatial Structure Based on Digital Elevation Models

Siwei Lin, Nan Chen, Zhuowen He
2021 Remote Sensing  
The slope spectrum method was used herein to solve the uncertainty issue of the determination on the watershed area.  ...  Complex network and P–N terrain, which are two effective methodologies to describe the spatial structure and topological relationship of the watershed, were adopted to simulate the spatial structure of  ...  Acknowledgments: The authors would like to express heartful thanks to three anonymous reviewers for their helpful comments, which significantly improved the quality of our paper.  ... 
doi:10.3390/rs13193926 fatcat:jvclrmwjqvb2rif5dxrccd4m3a
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