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Improving Super-Resolution Flood Inundation Mapping for Multispectral Remote Sensing Image by Supplying More Spectral Information
摘要： Super-resolution mapping is an effective technique in mapping ?ood inundation for multispectral remote sensing image. However, the traditional super-resolution ?ood inundation mapping (SRFIM) is unable to fully utilize the spectral information from multispectral remote sensing image band. In order to resolve this problem, a novel SRFIM by supplying more spectral information (SRFIM-MSI) is proposed to improve mapping accuracy. In the proposed SRFIM-MSI, the spectral information from the multispectral band is calculated by the normalized difference water index (NDWI). A spectral term constituted by NDWI is added into the traditional SRFIM. The proposed method is evaluated by using two Landsat 8 OLI multispectral data from the study area in Cambodia. The obtained results demonstrate that the proposed SRFIM-MSI produces better results than the traditional SRFIM methods.
关键词： super-resolution ?ood inundation mapping (SRFIM),spectral information,super-resolution mapping (SRM),Multispectral remote sensing image
更新于2025-09-09 09:28:46
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[IEEE 2017 IEEE Nuclear Science Symposium and Medical Imaging Conference (NSS/MIC) - Atlanta, GA, USA (2017.10.21-2017.10.28)] 2017 IEEE Nuclear Science Symposium and Medical Imaging Conference (NSS/MIC) - Rapid Kalman-Filter stabilization technique for single- and multi-detector systems
摘要： Most spectroscopic applications, especially homeland security relevant equipment relies on well-calibrated spectral data. A Kalman filter is applied to the known problem of stabilization, which means online calibration of a scintillation detector to a predefined reference peak. The method uses stochastic assumptions on the measurement uncertainties and an iterative update with new measurements. Introducing prior knowledge about the stochastic and continuously resupplying new spectral data to the filter enhances the predicted gain correction value and allows a rapid determination of this value. In multi-detector setups, the spectral alignment of data from all detectors is mandatory for performing data fusion or any further evaluations. The described Kalman technique also allows to perform this rapid cross-detector synchronization online, leading to matched up spectra at acquisition time.
关键词： multi-detector systems,stabilization,Kalman filter,scintillation detector,spectral alignment
更新于2025-09-09 09:28:46
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Sampling Rules for an Inhomogeneous Plane-wave Representation of Scattered Fields
摘要： Inhomogeneous plane waves (IPW) based on a linear contour deformation provide an accurate and concise field representation for scattering problems in which source and observation domains are visible within a limited angular sector. Given an error level, we derive closed-form expressions for the truncation limit, the sampling step and the contour slope that minimize the number of plane waves. A relation is drawn between the required number of plane waves and the degrees of freedom of the field, defined as the minimum number of orthonormal basis functions that represents scattered fields. The sampling rules are then applied to an efficient evaluation of the physical optics radiation integral.
关键词： Computational electromagnetics,spectral domain method,contour deformation,physical optics,error analysis,fast algorithm,degrees of freedom,field representation,Green’s function,scattering,inhomogeneous plane waves
更新于2025-09-09 09:28:46
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[IEEE OCEANS 2015 - MTS/IEEE Washington - Washington, DC (2015.10.19-2015.10.22)] OCEANS 2015 - MTS/IEEE Washington - Spectral response of marine submerged aquatic vegetation: A case study in Western Australia coast
摘要： Marine submerged aquatic vegetation (SAV) plays a vital role as habitats, nursery and feeding grounds for a wide range of marine aquatic and terrestrial life. Recently, remote sensing techniques have been successfully applied in marine benthic mapping in coastal waters. However, the majority of these techniques have focused on either seagrasses meadows or coral reefs. There are a few studies that have been published validating a methodology for mapping SAV on brown macroalgae (Sargassum spp., Ecklonia spp.), seagrasses, and/or other macroalgae groups by spectral response from remote sensing. Hence, we studied the in-situ optical properties of living macroalgae, seagrasses, and rubble. The spectral characteristics of varied SAV groups were measured using the high resolution FieldSpec? 4 Hi-Res portable spectroradiometer. The study site selected was the Shoalwater Islands Marine Park, Rockingham, Western Australia as it is one of the fifteen biodiversity hotspots in Australia. Correlation and Principle Component Analysis were employed to evaluate the differences between SAV groups. The results have documented the spectral features of SAV and their associated habitats in Shoalwater Islands Marine Park, Western Australia, and developed a spectral library to distinguish among seagrass species and algae groups (green, red, and brown benthic macroalgae). The implications of this study will contribute to estimate and detect the distribution and seasonal variation of SAV on a broader scale.
关键词： marine submerged aquatic vegetation,coral rubble,macroalgae,spectral reflectance,SAV
更新于2025-09-09 09:28:46
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0535 NIR technology as a process analytical tool for cheese inspection
摘要： The chemical composition of cheese is significantly related to quality, as it is responsible for its shelf life, yield and texture. However, conventional methods for determination of chemical composition are laborious and time-consuming. Fast assessment tools such as NIR spectroscopy and spectral imaging could be used for the quality control of cheeses. The advantage of this technique is that it allows several constituents to be measured simultaneously in a quick and nondestructive way. The objective of this work was to investigate spectral imaging combined with principal component analysis (PCA) for assessment of cheese samples. Spectral information of six varieties of cheese (Cheddar, coalho, Minas, mozzarella, prato and block processed cheese) were obtained using a spectral imaging system, between 928 and 2524 nm, with 6 nm intervals, resulting in 256 analyzed wavelengths. The first two principal components were responsible for 98.2% of the variation among samples, and the score plot presented good separation among samples of coalho cheese, mozzarella and Minas cheese. Loadings show that some peaks are strongly influenced by wavebands, associated to chemical bonds related to protein and fat. Spectral imaging combined with multivariate analysis can be a potential tool for fast cheese quality assessment.
关键词： quality control,spectral imaging,PCA
更新于2025-09-09 09:28:46
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[IEEE 2018 Days on Diffraction (DD) - St.Petersburg, Russia (2018.6.4-2018.6.8)] 2018 Days on Diffraction (DD) - Semi-analytical hybrid approach for modelling wave motion excited by a piezoelectric transducer in periodic layered composite with a crack
摘要： The paper presents a semi-analytical hybrid approach for modelling the interaction of a piezoelectric transducer and with a periodic elastic structure with a crack. It combines advantages of the frequency domain spectral element method using Gauss–Legendre–Lobatto polynomials and the boundary integral approach. The unknown crack-opening-displacement and the traction vector in the contact area are determined via Galerkin method.
关键词： semi-analytical hybrid approach,frequency domain spectral element method,Galerkin method,periodic elastic structure,boundary integral approach,piezoelectric transducer,crack
更新于2025-09-09 09:28:46
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Workshop on Lunar Calibration for Satellite Remote Sensing
摘要： Tracking climate variables at the levels of precision and accuracy required to detect global change requires satellite sensors to make highly consistent measurements that can be compared to measurements made at different times and with different instruments. Gaps in climate data records, such as those resulting from launch delay or instrument failure, and inconsistencies in radiometric scales between satellites can introduce unnecessary measurement error and thus undermine the credibility of fundamental climate data records. To address these issues, leading experts in satellite remote sensing and lunar observation and modeling assembled at the National Institute of Standards and Technology from 12-15 May 2012 for a workshop to discuss the utility of and strategies for using the Moon to calibrate satellite remote sensing measurements. This report summarizes the outcome of the workshop, including suggested steps to maximize the value of the Moon as an exoatmospheric calibration source for satellite remote sensing.
关键词： lunar spectral irradiance,remote sensing,calibration,moon,radiometry
更新于2025-09-09 09:28:46
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Empirical expressions for the spectral dependence of the refractive index for the case of thin-film silicon and some of its common alloys
摘要： We aim to model the spectral dependence of the refractive index associated with thin-film silicon, and some of its common alloys, using a series of elementary polynomial fits. For the purposes of this particular analysis, experimental data sets for the refractive index as a function of the photon energy corresponding to samples of thin-film silicon, and its alloy with germanium and carbon, prepared through evaporation, plasma enhanced chemical vapor deposition, and dc sputtering, are considered, this range of results providing a reasonably representative sampling over the thin-film silicon genome. The results of this analysis, i.e., the polynomials that arise from these fits, are explicitly tabulated. We believe that such models will offer the thin-film silicon community a number of advantages, including the ease with which such a result can be replicated, manipulated, and employed by fellow thin-film silicon researchers in their analyzes of this material system.
关键词： spectral dependence,alloys,refractive index,polynomial fits,thin-film silicon
更新于2025-09-09 09:28:46
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The Sun as a Guide to Stellar Physics || Models of Solar and Stellar Atmospheres
摘要： Our understanding of the Sun, other stars, and celestial objects in general is almost entirely based on observations and analysis of electromagnetic radiation in a broad wavelength range, from g-rays up to the radio. This radiation travels to us through the vast cosmic space, more than 8 min from the Sun and billions of years from distant universes. What we detect by our instruments is the result of a complex interaction between the photons and matter inside the objects under study, but also other interactions along the long path to us. To understand these interactions, we have to solve a coupled, generally nonlinear problem of how radiation is transported through such media and how the media, mostly various kinds of plasmas, are affected by penetrating radiation. In this way, we can model the spectrum emergent from various objects; this gives us a deep insight into the structure and dynamics of, e.g., solar and stellar atmospheres. We call this the spectral diagnostics. However, the actual state of an atmosphere may strongly depend on the spectral distribution of the internal radiation field via complex atomic processes, leading, for example, to heating or cooling of the plasma by radiation, along with other processes such as the heat conduction, wave dissipation, or magnetic heating. The whole complexity of these interactions is governed by a coupled system of (magneto)-hydrodynamical equations and equations describing the transport of radiation. This is called radiation hydrodynamics (RHD) and we will briefly describe it at the end of this chapter. On the other hand, considering only the radiative transfer in a prescribed model atmosphere, we deal with a “classical” astrophysical problem that was thoroughly studied during the past century, and to a great extent, the basic concepts were developed by solar physicists. This is usually called the theory of radiative transfer, which was regarded as a synonym of solar or stellar atmospheric physics (e.g., Physik der Sternatmospha¨ren by Unso¨ld, 1938). Among the atmospheres of various stars, the solar atmosphere has the unique privilege of providing us with insight into different structural patterns and their dynamical behavior. This then serves as a guide for our understanding of various phenomena on other stars, namely late-type cool stars. One of the most prominent stellar astrophysicists, D. Mihalas, who was engaged in both solar and stellar atmospheric research, once said, “My views have been colored by my long period of residence at the High Altitude Observatory in Boulder, where I was confronted daily by the ghastly reality of the Sun as seen at high time, spatial, and spectral resolution in a wide range of spectral bands. There is probably no more sobering an experience for a stellar atmospheres modeller than a detailed inspection of solar data!” (Mihalas, 1991). The theory of stellar atmospheres is summarized in an excellent textbook by Hubeny and Mihalas (2015).
关键词： non-LTE modeling,radiation hydrodynamics,spectral diagnostics,solar and stellar atmospheres,radiative transfer
更新于2025-09-09 09:28:46
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Theoretical investigation on spectral emissivity of thermal control coatings with optical-rough surface
摘要： A theoretical model for calculating the spectral emissivity of the thermal control coating with rough surfaces is proposed based on the Monte Carlo method in this paper. Instead of treating the surface of the coating as a smooth surface, a diffuse surface or a rough surface using an empirical formula, the model applies a Gaussian random rough surface to the spectral emissivity calculation of the coating. Firstly, the Gaussian rough surface is established, and its properties are mainly determined by two parameters: the root-mean-square roughness(δ) and the coherent length(l). Then the spectral emissivity model of the thermal control coating with the rough surface is established by Monte Carlo method. The directional spectral emissivity of the smooth surface and the rough surface with different roughness is compared. Finally, the reasons for their differences in spectral emissivity are explained.
关键词： Gaussian rough surface,Thermal control coating,Monte Carlo method,spectral emissivity
更新于2025-09-09 09:28:46