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Performance requirements for airborne imaging spectrometers

Michael E. Schaepman, Daniel Schlaepfer, Andreas A. Mueller, Michael R. Descour, Sylvia S. Shen
2002 Imaging Spectrometry VII  
at sensor radiances.  ...  Relevant changes to be detected in the observed variable are used to derive critical delta reflectances.  ...  The individual value of the delta radiance depends on a the absolute radiance value.  ... 
doi:10.1117/12.453345 fatcat:tjbm6c4xcnb3tdanz74cyhkm3q

Modeling the noise equivalent radiance requirements of imaging spectrometers based on scientific applications

Daniel Schläpfer, Michael Schaepman
2002 Applied Optics  
The wavelength dependent delta radiances are then derived at predefined radiance levels using a model of the sensor performance.  ...  A method for modeling the noise equivalent radiance at-sensor level is proposed.  ...  Delta Radiance Requirement The overall delta radiance requirement is derived as described in Section 2.3.  ... 
doi:10.1364/ao.41.005691 pmid:12269570 fatcat:o7an3z6zfnexjfnfrrimg6tz5m

Multiple-scaling methods for Monte Carlo simulations of radiative transfer in cloudy atmosphere

Zhen Wang, Shizhi Yang, Yanli Qiao, Shengcheng Cui, Qiang Zhao
2011 Journal of Quantitative Spectroscopy and Radiative Transfer  
Several one-dimensional and three-dimensional cloud fields were selected to validate the methods.  ...  The second method could decrease radiance noise to 0.60% for cumulus and accelerate convergence in optically thin regions.  ...  Acknowledgements The authors thank Victor Venema from Meteorological Institute of Bonn University for the high-resolution cloud fields and are grateful to two anonymous reviewers for their useful comments  ... 
doi:10.1016/j.jqsrt.2011.06.019 fatcat:o357jlvgknhc3frwd2q7hu4a54

Effects of optically shallow bottoms on upwelling radiances: Inhomogeneous and sloping bottoms

Curtis D. Mobley, Lydia K. Sundman
2003 Limnology and Oceanography  
Numerical simulations of 3D underwater radiances were made for environmental conditions observed in shallow Bahamian waters.  ...  The same holds true for uniformly sloping bottoms, whose 3D light fields can be modeled in terms of the 1D light fields computed for level bottoms, with errors of less than 10% for bottom slopes of 20Њ  ...  Because the idealized delta-function sensor has a zero field of view, the differences in the BMC3D and Hydrolight values, which are noticeable within ϳ3 m of the boundary, can be attributed to scattering  ... 
doi:10.4319/lo.2003.48.1_part_2.0329 fatcat:yv2323zrzjh6towvtmyzjm3tcm

Assimilating Satellite Radiances with a Local Ensemble Transform Kalman Filter (LETKF) Applied to the JMA Global Model (GSM)

Takemasa Miyoshi, Yoshiaki Sato
2007 SOLA : Scientific Online Letters on the Atmosphere  
Thus, the proposed localization technique is a promising way of assimilating satellite radiances within the LETKF system.  ...  It turns out that the vertical error covariance localization plays an essential role in assimilating satellite radiances.  ...  The source codes of the radiative transfer model RTTOV-8 were provided by EUMETSAT.  ... 
doi:10.2151/sola.2007-010 fatcat:bcx7k255wvgbnlsphr3wuze4r4

Delta radiance transfer

Bradford J. Loos, Derek Nowrouzezahrai, Wojciech Jarosz, Peter-Pike Sloan
2012 Proceedings of the ACM SIGGRAPH Symposium on Interactive 3D Graphics and Games - I3D '12  
Our implementation is simple, requiring a few small matrix-vector multiplications that generate a delta lightmap added to MRT's output, and does not adversely affect the performance benefits of the overall  ...  total) Figure 1 : Modular Radiance Transfer (a) does not accurately model light scattered onto "clutter objects" (e.g. the two boxes) (b) or indirect shadows (c) and interreflections (d) from clutter  ...  Using more modes to represent the direct light on the clutter would increase the quality of the interreflections (i.e. difference in the highlight on the ceiling in Figure 1 ).  ... 
doi:10.1145/2159616.2159648 dblp:conf/si3d/LoosNJS12 fatcat:lkupnltizban7poot5kgfp3oz4

NerfingMVS: Guided Optimization of Neural Radiance Fields for Indoor Multi-view Stereo [article]

Yi Wei, Shaohui Liu, Yongming Rao, Wang Zhao, Jiwen Lu, Jie Zhou
2021 arXiv   pre-print
In addition, we show that the guided optimization scheme does not sacrifice the original synthesis capability of neural radiance fields, improving the rendering quality on both seen and novel views.  ...  In this work, we present a new multi-view depth estimation method that utilizes both conventional reconstruction and learning-based priors over the recently proposed neural radiance fields (NeRF).  ...  depth priors into NeRF, significantly improving the geometry of the radiance fields.  ... 
arXiv:2109.01129v3 fatcat:zgtoq55zerbs5gwimqr5yhr2wi

Spatiotemporal Dynamics of Land Surface Temperature and Its Impact on the Vegetation

Ghulam Shabir Solangi, Altaf Ali Siyal, Pirah Siyal
2019 Civil Engineering Journal  
A correlation analysis between NDVI and the yield of the wheat crop of the Delta showed a positive relationship with R2 = 0.89.  ...  The present study was thus conducted to determine the spatiotemporal variations in the LST and its impact on the vegetation of the Indus delta, using satellite data for the past 27 years (1990-2017).  ...  -Pakistan Centre for Advanced Studies in Water (USPCAS-W), Mehran UET, Jamshoro, Pakistan for funding the project "Assessing Impact of Seawater intrusion on soil, water and environment in the Indus delta  ... 
doi:10.28991/cej-2019-03091368 fatcat:lwtr2xhfcrdobdc5ktsvp7j6dm

A vector radiative transfer model of coupled ocean–atmosphere system using matrix-operator method for rough sea-surface

Xianqiang He, Yan Bai, Qiankun Zhu, Fang Gong
2010 Journal of Quantitative Spectroscopy and Radiative Transfer  
PCOART can not only simulate the total radiance field in the coupled ocean-atmosphere system with wind-induced rough sea surface but also predict the polarization radiance field both in the atmosphere  ...  The model intercomparison is performed for several radiative transfer problems in the atmosphere and ocean, and the results show that PCOART can exactly predict the radiance fields for both flat and rough  ...  Acknowledgements The POLDER datasets were obtained from the French Space Agency. This work was supported by the National Basic  ... 
doi:10.1016/j.jqsrt.2010.02.014 fatcat:p4qaixbqabfbdazwifoemas4b4

Turbidity retrieval and monitoring of Danube Delta waters using multi-sensor optical remote sensing data: An integrated view from the delta plain lakes to the western–northwestern Black Sea coastal zone

Fabio N. Güttler, Simona Niculescu, Francis Gohin
2013 Remote Sensing of Environment  
During a selected 4-year temporal coverage (2006 to 2009), the turbidity gradients were simultaneously analyzed in the delta plain lakes and in the Black Sea western-northwestern coastal zone.  ...  Then, through an integrative analysis, the initial hypothesis of turbidity control by the Danube River inputs was tested in both areas (Delta plain and coastal zone).  ...  We thank also the Danube Delta Biosphere Reserve Authority and the Danube Delta National Institute (in particular Diana Bota) for the assistance during the field campaigns.  ... 
doi:10.1016/j.rse.2013.01.009 fatcat:64bjufohnvcsjk23o4felsecje

The impact of aerosols on polarized sky radiance: model development, validation, and applications

C. Emde, R. Buras, B. Mayer, M. Blumthaler
2009 Atmospheric Chemistry and Physics Discussions  
The polarized downwelling radiation field is calculated for various aerosol types showing the high sensitivity of polarized ultraviolet radiances to the particle microphysics.  ...  The analysis of polarized radiance measurements requires an accurate radiative transfer model.  ...  Cairns and the anonymous reviewer for their valuable comments which helped to improve the manuscript significantly.  ... 
doi:10.5194/acpd-9-17753-2009 fatcat:t2l7ovslrbgcxkub5shetpkkdm

Method of calibration to correct for cloud-induced wavelength shifts in the Aura satellite's Ozone Monitoring Instrument

Robert Voors, Marcel Dobber, Ruud Dirksen, Pieternel Levelt
2006 Applied Optics  
These wavelength variations are the result of rapid changes in time in the radiance levels during an individual observation in the presence of clouds or snow and ice.  ...  The in-flight wavelength calibration for the Ozone Monitoring Instrument is discussed.  ...  At the bottom right we show the observed shift (delta calibration) versus the precalculated shift (delta assignment).  ... 
doi:10.1364/ao.45.003652 pmid:16708112 fatcat:gxi4gvnnkndsrilouv7vp5noum

Photon conservation in scattering by large ice crystals with the SASKTRAN radiative transfer model

J. Truitt Wiensz, Adam E. Bourassa, Nick D. Lloyd, Aldona Wiacek, Randall V. Martin, Doug A. Degenstein
2012 Journal of Quantitative Spectroscopy and Radiative Transfer  
The methods introduced in this work are of particular interest in modeling limb radiances in the presence of thin cirrus clouds.  ...  Since computations shown this work are performed in a fully spherical model atmosphere, the computed radiances are not subject to the discontinuity at the horizon that is inherent in models using a plane-parallel  ...  Acknowledgements This work was supported by the Canadian Space Agency, the Natural Sciences and Engineering Research Council (Canada) and the European Space Agency.  ... 
doi:10.1016/j.jqsrt.2012.02.007 fatcat:z4xdfsracndb7b6x7wgerxueru

Methods Calculating the Slab Radiance Factor

Vladimir Budak, Dmitry Efremenko
2020 Proceedings of the 30th International Conference on Computer Graphics and Machine Vision (GraphiCon 2020). Part 2  
Then a simple iteration from the complete solution is performed to refine the angular distribution of the radiance factor.  ...  Strict analytical methods for solving the radiation transport equation (RTE) are often not highly effective for calculating the radiance factor.  ...  ⃡ ( , ) is referred to as the propagator and relates the radiance fields at spatial coordinates t and .  ... 
doi:10.51130/graphicon-2020-2-3-16 fatcat:4jh6rrgvbrg7bdhfsmonxhuu4i

Development of the Statistical Model for Monitoring Salinization in the Mekong Delta of Vietnam Using Remote Sensing Data and In-Situ Measurements

Nguyen Nguyen Vu, Le Van Trung, Tran Thi Van
2018 Proceedings (MDPI)  
The developed model will be an active contribution, providing managers with adaptation and response solutions suitable for intrusion in the estuary as well as the inner field of the Mekong Delta.  ...  Simulation of the salinity distribution along the river shows the intrusion of a 4 g/L salt boundary from the estuary to the inner field of more than 50 km.  ...  Table 5 shows the salt intrusion length of the 4 g/L salt boundary into the inner field from eight large estuaries in the study area.  ... 
doi:10.3390/iecg_2018-05362 fatcat:i3daziqaknhmhnzjkdbfwkqoce
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