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Məqalədə Landsat-8 peykinin məlumatları əsasında quru səthin şüalanmasının və temperaturunun qiymətləndirilməsinin əsas xüsusiyyətləri, ölçmə nəticələrinə təsir göstərən təsadüfi amillərin nəzərə alınması ilə bağlı mövcud nəzəri və metodiki məsələlərin həlli üsulları nəzərdən keçirilmişdir. İstifadə olunan üsul vasitəsi ilə, müxtəlif növ səthlərin spektral şüalanma əmsallarının dəyişmə xüsusiyyətləri xətti reqressiya göstəricilərinin müəyyənləşdirilməsinə əsaslanmışdır. Temperaturun baxılan üsulla təyin olunmasında orta kvadratik xətanın qiyməti 0,33-0,76 K intervalında dəyişir. Təklif olunan metod əsasında səthin şüalanma əmsalının orta kvadratik xətasının qiyməti 0,102-dən artıq olmur., В статье рассмотрены основные особенности оценки радиации и температуры сухой поверхности на основе данных системы Landsat-8, методы решения существующих теоретических и методологических вопросов, связанных со случайными факторами, влияющими на результаты измерений. С помощью используемого метода характеристики, изменчивости спектральных коэффициентов излучения различных типов поверхностей основаны на определении индексов линейной регрессии. Величина средней квадратичной погрешности определения температуры рассматриваемым методом колеблется в пределах 0,33-0,76К. На основе предлагаемого метода значение среднеквадратичной ошибки коэффициента излучения поверхности не превышает 0,102., The article considers the main features of the assessment of radiation and temperature of the dry surface on the basis of data from the Landsat-8 system, methods for solving existing theoretical and methodological issues related to the random factors affecting the measurement results. Using the method used, the variability characteristics of the spectral radiation coefficients of different types of surfaces were based on the determination of linear regression indices. The value of the mean quadratic error in determining the temperature by the considered method varies in the range of 0.33-0.76 K. Based on the proposed method, the value of the mean square error of the surface radiation coefficient does not exceed 0.102., Научные труды, Выпуск 2.24.2022 (1-77) 2022, Pages 11-15

Evolution in the Copernicus Space Component is foreseen in the mid-2020s to meet priority user needs not addressed by the existing infrastructure, and/or to reinforce existing services. In this context, the European Commission is intending to evaluate the overall potential utility of a complementary Copernicus hyperspectral mission to be added to the Copernicus Sentinels fleet. Hyperspectral imaging is a powerful remote sensing technology that, allowing the characterization and quantification of Earth surface materials, has the potential to deliver significant enhancements in quantitative value-added products. This study aims to illustrate the interaction methodology that was set up to collect and assess user-driven requirements in different thematic areas to demonstrate the potential benefit of a future Copernicus hyperspectral mission. Therefore, an ad hoc interaction matrix was circulated among several user communities to gather preferences about hyperspectral-based products and services. The results show how the involvement of several user communities strengthens the identification of these user requirements. Moreover, the requirement evaluation is used to identify potential opportunities of hyperspectral imaging in addressing operational needs associated with policy obligations at European, national, and local levels. The frequency distribution of spectral range classes and spatial and temporal resolutions are also derived from the preference expressed by the user communities in each thematic area investigated.

The influence of heat treatment on the transmission of silicate thin films prepared by gelation from aqueous solutions of sodium silicate (water glass) is investigated. It is demonstrated that the initial films are characterized by a strong absorption in the IR range due to the presence of hydroxyl groups. The heat treatment of the films at temperatures in the range 150-250°C leads to the step-by-step removal of water from the films and, as a consequence, to an almost complete transmission in the high-frequency IR spectral range. An increase in the heat treatment temperature to 580°C is accompanied by the loss of transparency, most likely, as a result of the pore formation in the film. © 2008 MAIK Nauka.

The lead-based complex perovskite Pb(Yb0.5Ta0.5)O3, exhibiting long-range B-site cation ordering has been studied by Raman spectroscopy. The investigation has been performed as a function of temperature ranging from 250 K to a lower temperature 10 K in the spectral range 1020-20 cm-1. The spectra are analyzed through the characteristic parameters: peak position and line width of phonon modes. Significant decrease in the asymmetric phonon line broadening with noticeable shift of the peak positions and appearance of new modes in the Raman spectra at low temperature have been observed. The local distortion in the lattice has been enhanced substantially at low temperature. The splitting of the F2g modes suggests that the orthorhombic phase is stabilized at low temperature. The two F2g modes (60 and 518 cm-1) show soft mode behavior. � 2007 Elsevier B.V. All rights reserved.

In this paper, for their use as nanoluminophors on color-conversion white light emitting diodes (LEDs), we present spectrally resolved relative quantum efficiency and relative color (photon) conversion efficiency of CdSe/ZnS core/shell nanocrystal (NC) emitters in the solid-state film. We observe that both the averaged relative quantum efficiency and the averaged relative photon conversion efficiency of these NC solids increase with the increasing photon pump energy. Therefore, the excitation LED platform emitting at shorter wavelengths facilitates such NC luminophor solids to be more efficiently pumped optically. Furthermore, we investigate the spectral time-resolved spectroscopy of NCs in solution and in film with 0.4-2.4 nmol integrated number of NCs in the spectral range of 610-660 nm. We observe that the average lifetime of NCs increases toward longer wavelengths as the number of in-film NCs increases. With the increased amount of NCs, the average lifetime increases even further and the emission of NCs is shifted further toward red. This is attributed to the enhanced nonradiative energy transfer between these NCs due to the inhomogeneous size distribution. Thus, in principle, for fine tuning of the collective color of NCs for color-conversion LEDs, it is important to control the energy transfer by changing the integrated number of NCs. © 2009 American Institute of Physics.

Atmospheric aerosol particles affect the Earth's radiative balance both in the cloud-free and the cloudy atmosphere. The direct effect of aerosols is related with scattering and absorption of solar radiation, and as a consequence, reduction of the amount of radiation reaching the surface. The best parameter that quantifies this effect is the aerosol extinction, which can be derived from vertical, as well as, horizontal measurements. The purpose of this paper is to compare the aerosol optical properties registered by two types of instruments. The first is a standard 5-wavelength hand-held sun photometer yielding the vertical column extinction, the second a 7-wavelength transmissometer developed at TNO. This multi-band transmissometer provides horizontal, path-integrated transmission data at 7 wavelengths within the visible/infra red spectral range. The data used in the comparison were collected during an experiment near Scripps Pier in La Jolla near San Diego, in November 2006.

Atmospheric aerosol particles affect the Earth's radiative balance both in the cloud-free and the cloudy atmosphere. The direct effect of aerosols is related with scattering and absorption of solar radiation, and as a consequence, reduction of the amount of radiation reaching the surface. The best parameter that quantifies this effect is the aerosol extinction, which can be derived from vertical, as well as, horizontal measurements. The purpose of this paper is to compare the aerosol optical properties registered by two types of instruments. The first is a standard 5-wavelength hand-held sun photometer yielding the vertical column extinction, the second a 7-wavelength transmissometer developed at TNO. This multi-band transmissometer provides horizontal, path-integrated transmission data at 7 wavelengths within the visible/infra red spectral range. The data used in the comparison were collected during an experiment near Scripps Pier in La Jolla near San Diego, in November 2006.

REFIR is a Fourier Transform Spectrometer designed to measure the upwelling IR Earth's emission from space in the spectral range 100 to 1000 cm -1 with an unapodized spectral resolution of about 0.5 cm -1. One of the main scientific objectives of REFIR is to monitor the far IR planetary emission and the principal drivers of this emission, with particular attention being paid to the poorly understood mid and upper troposphere. The expected retrieval performance for temperature and water vapor profiles, from a subset of REFIR measurements, is evaluated and presented in this paper. ©2003 Copyright SPIE - The International Society for Optical Engineering.