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Conference on Nanophotonics, Nanostructure and Nanometrology

作者： Yue, CF Yang, GL He, ZJ Yu, LS Peng, L S China Normal Univ Dept Phys Guangzhou 510631 Peoples R China

ISBN: (纸本)0819455903

Based on the analysis of Dynamic Light Scattering(DLS) technique, and toke the measurement Of SiO2 particle (size from 200nm-1300nm) using BI-200SM Goniometer as an example, this paper discussed the factors and the effects brought by these factors on measurement result. The analyzed factors include: poly of particles, inversion algorithm, irradiate time of laser on particles, surrounding temperature and the kind of liquid. Some phenomena was observed, such as: the difference among results by different algorithms changed with the change of particles' poly, the measurement result increased slightly as time went on, the size of particles increased greatly as the temperature was increased, the scattering light intensity was been depressed badly and the liquid with particles appeared unusually transparent and clean when SiO2 particles were put into ethanol.

关键词： Dynamic Light Scattering micro and nano-particle monodisperse polydisperse poly inversion algorithms

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A PRE-OPERATIONAL ALGORITHM FOR THE RETRIEVAL OF SNOW DEPTH AND SOIL MOISTURE FROM AMSR-E DATA 30

A PRE-OPERATIONAL ALGORITHM FOR THE RETRIEVAL OF SNOW DEPTH ...

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IEEE International Geoscience and Remote Sensing Symposium

作者： Santi, Emanuele Pettinato, Simone Brogioni, Marco Macelloni, Giovanni Montomoli, Francesco Paloscia, Simonetta Pampaloni, Paolo CNR IFAC Florence Italy

ISBN: (纸本)9781424495665

This work deals with mapping snow water equivalent as well as soil moisture at low resolution from multifrequency microwave radiometers. The algorithm developed and implemented in this work produces the spatial distribution at regional scale of snow depth (SD) and of soil moisture (SMC) of snow free areas by using the brightness temperatures of the Advanced Multifrequency Scanning Radiometer (AMSR-E).

关键词： Snow Depth Soil Moisture Content AMSR-E inversion algorithms

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MEASUREMENT OF WATER-VAPOR AND CLOUD LIQUID WATER-CONTENT BY A DUAL-CHANNEL GROUND-BASED MICROWAVE RADIOMETER

MEASUREMENT OF WATER-VAPOR AND CLOUD LIQUID WATER-CONTENT BY...

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1991 INTERNATIONAL GEOSCIENCE AND REMOTE SENSING SYMP - REMOTE SENSING : GLOBAL MONITORING FOR EARTH MANAGEMENT ( IGARSS 91 )

作者： ZHAO, CL CAI, HQ SONG, YD LIN, B

ISBN: (纸本)0879426756

The design principle and structural features of a new type of dual-channel ground-based microwave radiometer for measurement of water vapor and cloud liquid water content in the troposphere are discussed. A method independent of radiosonde data is used for system absolute calibrations. A statistical method for retrieving the total water vapor and cloud liquid water content and a nonlinear iterative algorithm for retrieving the water vapor profiles in the troposphere are discussed. A comparison is conducted between the measurement of the integrated amounts of water vapor and the tropospheric vapor profiles by the radiometer and the radiosonde data.

关键词： DIGITAL INSTRUMENT CALIBRATION inversion algorithms

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MEASUREMENT OF WATER VAPOR AND CLOUD LIQUID WATER CONTENT BY A DUAL-CHANNEL GROUND-BASED MICROWAVE RADIOMETER

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Acta meteorologica Sinica 1991年第3期5卷 299-306页

作者：赵从龙蔡化庆宋玉东林滨徐培源 Academy of Meteorological Science State Meteorological AdministrationBeijing Institute of Electronic Physics University of Science and Technology of ShanghaiShanghai

The design principle and structural features of a new type dual-channel ground-based microwave radiometer for measurement of water vapor and liquid water in troposphere are discussed. A method independent of radiosonde data is used for system absolute calibrations. A statistical method for retrieving the total water vapor and cloud liquid water content and a nonlinear iterative algorithm for retrieving the water vapor profiles in the troposphere are discussed. Comparison is conducted between the measurement of the integrated amounts of the water vapor and the tropospheric vapor profiles by the radiometer and the radiosonde data.

关键词： digital instrument calibration inversion algorithms microwave radiometer

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AN ANALYSIS OF THE CAPABILITIES OF COSMO-SKYMED AND RADARSAT SYSTEMS FOR AGRICULTURAL AREA MONITORING

AN ANALYSIS OF THE CAPABILITIES OF COSMO-SKYMED AND RADARSAT...

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IEEE International Geoscience and Remote Sensing Symposium (IGARSS)

作者： Paloscia, S. Pettinato, S. Santi, E. Notarnicola, C. Greifeneder, F. Cuozzo, G. Nicolini, I. Demir, B. Bruzzone, L. CNR IFAC Florence Italy EURAC Bolzano Italy Univ Trento Trento Italy

ISBN: (纸本)9781479979295

This research aims at analyzing the integration of C and X band data collected from Radarsat2 (RS2) and COSMO-SkyMed (CSK) systems on some test areas in Italy, in order to estimate the main geophysical parameters of soil and vegetation, such as soil moisture and vegetation biomass. A check of the sensitivity of SAR signal to the soil parameters was first carried out on both test sites. Over the South-Tyrol area a retrieval approach based on the Support Vector Regression methodology, which was already tested in this area using C-band data from ENVISAT/ASAR data, was carried out. From these preliminary results it can be concluded that X-band images combined with C-band images could provide valuable information for the retrieval of SMC, even though further investigations should be carried out on a larger time-series and larger set of samples.

关键词： Cosmo-SkyMed Radarsat2 agricultural areas soil moisture retrieval inversion algorithms

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COSMO-SKYMED AND RADARSAT IMAGE INTEGRATION FOR SOIL MOISTURE AND VEGETATION BIOMASS MONITORING 37

COSMO-SKYMED AND RADARSAT IMAGE INTEGRATION FOR SOIL MOISTUR...

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IEEE International Geoscience & Remote Sensing Symposium

作者： Paloscia, S. Pettinato, S. Santi, E. Notarnicola, C. Greifeneder, F. Cuozzo, G. IFAC CNR Florence Italy EURAC Bolzano Italy

ISBN: (纸本)9781509049516

This research aims at analyzing the integration of C and X band data collected from Radarsat2 (RS2) and COSMO-SkyMed (CSK) systems on two Italian test areas, located in South-Tyrol and in Tuscany, close to Florence, to estimate soil moisture (SMC, in %) and vegetation biomass (PWC, in kg/m(2)). Two retrieval approaches based on Support Vector Regression (SVR) and Artificial Neural Network (ANN) have been applied to these areas. Looking at the preliminary results, it has been noted that the integration of X and C band images could provide valuable information for the retrieval of SMC, even though further investigations should be carried out on a larger time-series and set of samples. On the South Tyrol test area, SVR methods provided an accuracy in the estimate of SMC with determination coefficient, R-2> 0.85 and root mean square error, RMSE.<= 4%. By using X band alone, the result obtained is worse: ANN algorithm resulted in R2 from 0.35 to 0.8 and RMSE from 6 to 2 (% SMC), depending on the polarization combinations considered as input. X band allowed instead retrieving the PWC of cereal fields with a satisfactory accuracy (R-2=0.94 and RMSE=0.35 Kg/m(2)).

关键词： Cosmo-SkyMed Radarsat2 agricultural areas soil moisture retrieval inversion algorithms

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PROGRESS ON A NEW ANALYTICAL ALGORITHM TO RETRIEVE INHERENT OPTICAL PROPERTIES FROM OCEAN COLOR REMOTE SENSING 38

PROGRESS ON A NEW ANALYTICAL ALGORITHM TO RETRIEVE INHERENT ...

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38th IEEE International Geoscience and Remote Sensing Symposium (IGARSS)

作者： Twardowski, Michael Tonizzo, Alberto Florida Atlantic Univ Harbor Branch Oceanog Inst Ft Pierce FL 34946 USA Sunstone Sci LLC Vero Beach FL 32963 USA

ISBN: (纸本)9781538671504

Approximations are vital to interpret ocean color remote sensing since it is not possible to analytically invert the full the radiative transfer (RT) equation. RT approximations to date have almost exclusively relied on relating [b(b) / (a + b(b))] to remote sensing reflectance (r(RS)). This shifts uncertainty for several parameters associated with viewing geometry and the volume scattering function into the proportionality. Zaneveld [1] developed a RT approximation that explicitly incorporates these aspects in a fully analytical relationship, but it has not been rigorously evaluated to date. We rework the Zaneveld approximation so that rRS is only dependent on bb and a, while retaining explicit dependencies on the shape of the volume scattering function and viewing geometry. The algorithm is fully spectral. We also, for the first time, demonstrate inversion of this algorithm to derive inherent optical properties (IOPs) backscattering bb and absorption a. The algorithm shows promise for a new operational ocean color retrieval algorithm.

关键词： Radiative Transfer Ocean Color inversion algorithms

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Requirements for accurate estimation of anisotropic material parameters by magnetic resonance elastography: A computational study

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MAGNETIC RESONANCE IN MEDICINE 2017年第6期78卷 2360-2372页

作者： Tweten, D. J. Okamoto, R. J. Bayly, P. V. Washington Univ Mech Engn & Mat Sci 1 Brookings Dr St Louis MO 63105 USA Washington Univ Biomed Engn St Louis MO USA

PurposeTo establish the essential requirements for characterization of a transversely isotropic material by magnetic resonance elastography (MRE). Theory and MethodsThree methods for characterizing nearly incompressible, transversely isotropic (ITI) materials were used to analyze data from closed-form expressions for traveling waves, finite-element (FE) simulations of waves in homogeneous ITI material, and FE simulations of waves in heterogeneous material. Key properties are the complex shear modulus (2), shear anisotropy =1/2-1, and tensile anisotropy =E1/E2-1. ResultsEach method provided good estimates of ITI parameters when both slow and fast shear waves with multiple propagation directions were present. No method gave accurate estimates when the displacement field contained only slow shear waves, only fast shear waves, or waves with only a single propagation direction. Methods based on directional filtering are robust to noise and include explicit checks of propagation and polarization. Curl-based methods led to more accurate estimates in low noise conditions. Parameter estimation in heterogeneous materials is challenging for all methods. ConclusionsMultiple shear waves, both slow and fast, with different propagation directions, must be present in the displacement field for accurate parameter estimates in ITI materials. Experimental design and data analysis can ensure that these requirements are met. Magn Reson Med 78:2360-2372, 2017. (c) 2017 International Society for Magnetic Resonance in Medicine.

关键词： MR elastography anisotropy transversely isotropic material shear waves inversion algorithms heterogeneity

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Mapping Woody Volume of Mediterranean Forests by Using SAR and Machine Learning: A Case Study in Central Italy

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REMOTE SENSING 2021年第4期13卷 809-809页

作者： Santi, Emanuele Chiesi, Marta Fontanelli, Giacomo Lapini, Alessandro Paloscia, Simonetta Pettinato, Simone Ramat, Giuliano Santurri, Leonardo Natl Res Council Italy IFAC CNR Inst Appl Phys Via Madonna Piano 10 I-50019 Florence Italy Natl Res Council Italy IBE CNR Inst BioEcon Via Madonna Piano 10 I-50019 Florence Italy

In this paper, multi-frequency synthetic aperture radar (SAR) data at L- and C-bands (ALOS PALSAR and Envisat/ASAR) were used to estimate forest biomass in Tuscany, in Central Italy. The ground measurements of woody volume (WV, in m(3)/ha), which can be considered as a proxy of forest biomass, were retrieved from the Italian National Forest Inventory (NFI). After a preliminary investigation to assess the sensitivity of backscatter at C- and L-bands to forest biomass, an approach based on an artificial neural network (ANN) was implemented. The ANN was trained using the backscattering coefficient at L-band (ALOS PALSAR, HH and HV polarization) and C-band (Envisat ASAR in HH polarization) as inputs. Spatially distributed WV values for the entire test area were derived by the integration (fusion) of a canopy height map derived from the Ice, Cloud, and Land Elevation Geoscience Laser Altimeter System (ICESat GLAS) and the NFI data, in order to build a significant ground truth dataset for the training stage. The analysis of the backscattering sensitivity to WV showed a moderate correlation at L-band and was almost negligible at C-band. Despite this, the ANN algorithm was able to exploit the synergy of SAR frequencies and polarizations, estimating WV with average Pearson's correlation coefficient (R) = 0.96 and root mean square error (RMSE) similar or equal to 39 m(3)/ha when applied to the test dataset and average R = 0.86 and RMSE similar or equal to 75 m(3)/ha when validated on the direct measurements from the NFI. Considering the heterogeneity of the scenario (Mediterranean mixed forests in hilly landscape) and the small amount of available ground measurements with respect to the spatial variability of different plots, the obtained results can be considered satisfactory. Moreover, the successful use of WV from global maps for implementing the algorithm suggests the possibility to apply the algorithm to wider areas or even to global scales.

关键词： SAR forest biomass woody volume ANN inversion algorithms

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AN ANALYSIS OF THE CAPABILITIES OF COSMO-SKYMED AND RADARSAT SYSTEMS FOR AGRICULTURAL AREA MONITORING

AN ANALYSIS OF THE CAPABILITIES OF COSMO-SKYMED AND RADARSAT...

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IEEE International Geoscience and Remote Sensing Symposium

作者： S. Paloscia S. Pettinato E. Santi C. Notarnicola F. Greifeneder G. Cuozzo I. Nicolini B. Demir L. Bruzzone IFAC-CNR EURAC University of Trento

ISBN: (纸本)9781479979301

关键词： Cosmo-SkyMed Radarsat2 Agricultural areas Soil moisture retrieval inversion algorithms

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