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Spectral reflectance and emissivity of man-made surfaces contaminated with environmental effects

Kristin-Elke Strackerjan
2008 Optical Engineering: The Journal of SPIE  
These measurements enable simulation of optical images with objects in the scene attributed with realistic surface reflectance and emissivity spectra.  ...  In particular, high resolution spectral reflectance and emissivity curves are presented for several man-made surfaces ͑asphalt, concrete, roofing shingles, and vehicles͒ under varying amounts of sand and  ...  An artificial light source was used to illuminate the materials for the measurement.  ... 
doi:10.1117/1.3000433 fatcat:vdpnmjqswrf3lbqu42kr3qfbym

Optical remote sensing of vegetation: Modeling, caveats, and algorithms

R.B. Myneni, S. Maggion, J. Iaquinta, J.L. Privette, N. Gobron, B. Pinty, D.S. Kimes, M.M. Verstraete, D.L. Williams
1995 Remote Sensing of Environment  
Modeling of top-of-the-atmosphere and top-of-the-canopy radiance field is developed as boundary value problems in radiative transfer.  ...  The parameterization of the constituentfunctions with simple models and/or empirical data is outlined together with numerical solution methods and examples of results of model validation.  ...  The linear mixing model assumes that vegetation and soil radiances can be combined linearly with weights proportional to ground cover.  ... 
doi:10.1016/0034-4257(94)00073-v fatcat:qi7ncax7m5dwnb6geagehqotwm

Joint retrieval of aerosol and water-leaving radiance from multi-spectral, multi-angular and polarimetric measurements over ocean

F. Xu, O. Dubovik, P.-W. Zhai, D. J. Diner, O. V. Kalashnikova, F. C. Seidel, P. Litvinov, A. Bovchaliuk, M. J Garay, G. van Harten, A. B. Davis
2016 Atmospheric Measurement Techniques Discussions  
The Markov chain method is used to model RT in the aerosol/Rayleigh mixed layer and the doubling method is used for the uniform layers of the atmosphere-ocean system.  ...  An optimization approach has been developed for simultaneous retrieval of aerosol properties and normalized water-leaving radiance (nLw) from multi-spectral, multi-angular, and polarimetric observations  ...  of University of Massachusetts Boston for discussing the AERONET Ocean Color product of normalized water-leaving radiance.  ... 
doi:10.5194/amt-2015-394 fatcat:52somuj3pvhdja5o3xnkrkjfmi

Joint retrieval of aerosol and water-leaving radiance from multispectral, multiangular and polarimetric measurements over ocean

Feng Xu, Oleg Dubovik, Peng-Wang Zhai, David J. Diner, Olga V. Kalashnikova, Felix C. Seidel, Pavel Litvinov, Andrii Bovchaliuk, Michael J. Garay, Gerard van Harten, Anthony B. Davis
2016 Atmospheric Measurement Techniques  
The Markov chain method is used to model RT in the aerosol/Rayleigh mixed layer and the doubling method is used for the uniform layers of the atmosphere–ocean system.  ...  </strong> An optimization approach has been developed for simultaneous retrieval of aerosol properties and normalized water-leaving radiance (nLw) from multispectral, multiangular, and polarimetric observations  ...  of University of Massachusetts Boston for discussing the AERONET Ocean Color product of normalized water-leaving radiance.  ... 
doi:10.5194/amt-9-2877-2016 fatcat:yecv2i4nijgnneafplm6i6hq34

Challenges in Methane Column Retrievals from AVIRIS-NG Imagery over Spectrally Cluttered Surfaces: A Sensitivity Analysis

Minwei Zhang, Ira Leifer, Chuanmin Hu
2017 Remote Sensing  
The study used the residual radiance method, with sensitivity derived from MODTRAN (MODerate resolution atmospheric correction TRANsmission) simulations of column methane (XCH 4 ).  ...  A comparison between efforts to detect methane anomalies by a simple band ratio approach from the Airborne Visual Infrared Imaging Spectrometer-Classic (AVIRIS-C) data for the Kern Front oil field, Central  ...  We also appreciate the contribution from CIRPAS, of the Naval Postgraduate School and NASA Ames Research Center, Richard Koyler, and Christopher Melton of Bubbleology Research International, for providing  ... 
doi:10.3390/rs9080835 fatcat:ytkybsze4vdp3nwcnmbbl4ivia

Inverse Path Tracing for Joint Material and Lighting Estimation [article]

Dejan Azinović, Tzu-Mao Li, Anton Kaplanyan, Matthias Nießner
2019 arXiv   pre-print
However, illumination and material reconstruction remain less studied, with current approaches assuming very simplified models for materials and illumination.  ...  To this end, we introduce a novel optimization method using a differentiable Monte Carlo renderer that computes derivatives with respect to the estimated unknown illumination and material properties.  ...  Acknowledgements This work is funded by Facebook Reality Labs. We also thank the TUM-IAS Rudolf Mößbauer Fellowship (Focus Group Visual Computing) for their support.  ... 
arXiv:1903.07145v1 fatcat:exp5b2tqo5dadpwnu6duoooocy

A framework for transient rendering

Adrian Jarabo, Julio Marco, Adolfo Muñoz, Raul Buisan, Wojciech Jarosz, Diego Gutierrez
2014 ACM Transactions on Graphics  
We propose a novel density estimation technique that allows reusing sampled paths to reconstruct time-resolved radiance, and devise new sampling strategies that take into account the distribution of radiance  ...  Acknowledgments We want to thank the reviewers for their insightful comments, and Mubbasir Kapadia for the link to sound rendering papers.  ...  In all the scenes light emission occurs at t = 0 with a delta pulse 2 .  ... 
doi:10.1145/2661229.2661251 fatcat:47dhu6kltbbzbpt4y4lgh74chm

Surface-roughness considerations for atmospheric correction of ocean color sensors 1: The Rayleigh-scattering component

Howard R. Gordon, Menghua Wang
1992 Applied Optics  
In the case of the coastal zone color scanner bands, we show that for moderate solar zenith angles the error is generally below the 1 digital count level, except near the edge of the scan for high wind  ...  spectral radiance in certain situations.  ...  Radiation fields with intermediate values of P are partially polarized. Fields with V = 0 and P • 0 are linearly polarized; otherwise they are elliptically polarized.  ... 
doi:10.1364/ao.31.004247 pmid:20725409 fatcat:tallyqniqvb3rmkxuevji6jqny

Intercomparison of retrieval algorithms for the specific surface area of snow from near-infrared satellite data in mountainous terrain, and comparison with the output of a semi-distributed snowpack model

A. Mary, M. Dumont, J.-P. Dedieu, Y. Durand, P. Sirguey, H. Milhem, O. Mestre, H. S. Negi, A. A. Kokhanovsky, M. Lafaysse, S. Morin
2013 The Cryosphere  
</strong> This study compares different methods to retrieve the specific surface area (SSA) of snow from satellite radiance measurements in mountainous terrain.  ...  The added-value of the anisotropy correction was not significant in our case, which may be explained by the presence of mixed pixels and surface roughness.  ...  Harter for their help and useful discussions. A. Mary thanks the Ecole Nationale de la Méteorologie for the opportunity to work on this subject, and C.  ... 
doi:10.5194/tc-7-741-2013 fatcat:52leygf3nfdstldiyend2mkaxq

Synthesis of Environment Maps for Mixed Reality

David R. Walton, Diego Thomas, Anthony Steed, Akihiro Sugimoto
2017 2017 IEEE International Symposium on Mixed and Augmented Reality (ISMAR)  
When rendering virtual objects in a mixed reality application, it is helpful to have access to an environment map that captures the appearance of the scene from the perspective of the virtual object.  ...  The method combines the output from both cameras to correct for their limited field of view and the displacement from the virtual object, producing complete environment maps suitable for rendering the  ...  The authors would like to thank the reviewers for their helpful feedback, including a suggested improvement to the brightness adjustment approach.  ... 
doi:10.1109/ismar.2017.24 dblp:conf/ismar/WaltonTSS17 fatcat:wayheqhqnjckxhsgfij4s2km7i

State of the art in photon density estimation

Toshiya Hachisuka, Andrew Selle, Ben Spencer, Wojciech Jarosz, Guillaume Bouchard, Per Christensen, Jeppe Revall Frisvad, Wenzel Jakob, Henrik Wann Jensen, Michael Kaschalk, Claude Knaus
2012 ACM SIGGRAPH 2012 Posters on - SIGGRAPH '12  
Figure 7: Alarm clocks illuminated by a desk lamp. The desk lamp with a light bulb is outside the view and illuminates the clocks. The scene is rendered using a thin lens model for depth-of-field.  ...  SPPM robustly handles illumination by the desk lamp as well as depth-of-field in the same rendering time with less memory consumption.  ... 
doi:10.1145/2343483.2343489 fatcat:lmmwllfeyjd5tibrm3yzkntcly

Surface radiation budgets in support of the GEWEX Continental-Scale International Project (GCIP) and the GEWEX Americas Prediction Project (GAPP), including the North American Land Data Assimilation System (NLDAS) project

Rachel T. Pinker
2003 Journal of Geophysical Research  
The satellite input to the model for each grid cell is clear sky radiance, composite clear sky radiance (this is the ''clearest radiance'' seen during several days), cloudy radiance, and fractional cloud  ...  ¼ n cloudy þ f * n mixed n 0 clear ¼ n clear þ ð1 À f Þ * n mixed ; where f ¼ A mixed À A th ð Þ = 35% albedo À A th ð Þ A mixed is the mean albedo of the mixed pixels, and A th ¼ A 1min þ k 3 s 1min  ... 
doi:10.1029/2002jd003301 fatcat:lyurfeso55atzmztrfwycekjty

Fast Lidar and Radar Multiple-Scattering Models. Part II: Wide-Angle Scattering Using the Time-Dependent Two-Stream Approximation

Robin J. Hogan, Alessandro Battaglia
2008 Journal of the Atmospheric Sciences  
An efficient method is described for calculating the time-dependent returns from such a medium by splitting the photons into those that have taken a near-direct path out to and back from a single backscattering  ...  By assuming that the lateral distribution can be described by a Gaussian, the fraction of photons within the receiver field of view may be calculated.  ...  We thank Tamás Várnai for co-  ... 
doi:10.1175/2008jas2643.1 fatcat:wtzmfkni6vhexc4kxjqlibqycy

Near-infrared remote sensing of Los Angeles trace gas distributions from a mountaintop site

D. Fu, T. J. Pongetti, J.-F. L. Blavier, T. J. Crawford, K. S. Manatt, G. C. Toon, K. W. Wong, S. P. Sander
2013 Atmospheric Measurement Techniques Discussions  
Algorithms are described for transforming the measured interferograms into spectra, and for deriving column abundances from the spectra along with estimates of the measurement precision and accuracy.  ...  From its mountaintop location at an altitude of 1673 m, the instrument points at a programmed sequence of ground target locations in the Los Angeles basin, recording spectra of reflected near-IR solar  ...  Additional diagnostics include imaging of the Haidinger fringes at the field stop when the FTS is illuminated by scattered light from a beam-expanded He : Ne laser, and recordings of the ILS from a near-IR  ... 
doi:10.5194/amtd-6-8807-2013 fatcat:au3sl32vkzaaza5fnafsoih3f4

Near-infrared remote sensing of Los Angeles trace gas distributions from a mountaintop site

D. Fu, T. J. Pongetti, J.-F. L. Blavier, T. J. Crawford, K. S. Manatt, G. C. Toon, K. W. Wong, S. P. Sander
2014 Atmospheric Measurement Techniques  
Algorithms are described for transforming the measured interferograms into spectra, and for deriving column abundances from the spectra along with estimates of the measurement precision and accuracy.  ...  From its mountaintop location at an altitude of 1673 m, the instrument points at a programmed sequence of ground target locations in the Los Angeles basin, recording spectra of reflected near-IR solar  ...  Additional diagnostics include imaging of the Haidinger fringes at the field stop when the FTS is illuminated by scattered light from a beam-expanded He : Ne laser, and recordings of the ILS from a near-IR  ... 
doi:10.5194/amt-7-713-2014 fatcat:ekhr5ajybzghdbzzphhgz5v6zm
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