Search results for "satellite"
showing 10 items of 1031 documents
Polar motion prediction using the combination of SSA and Copula-based analysis
2018
The real-time estimation of polar motion (PM) is needed for the navigation of Earth satellite and interplanetary spacecraft. However, it is impossible to have real-time information due to the complexity of the measurement model and data processing. Various prediction methods have been developed. However, the accuracy of PM prediction is still not satisfactory even for a few days in the future. Therefore, new techniques or a combination of the existing methods need to be investigated for improving the accuracy of the predicted PM. There is a well-introduced method called Copula, and we want to combine it with singular spectrum analysis (SSA) method for PM prediction. In this study, first, we…
Improvements in land surface temperature retrieval from the Landsat series thermal band using water vapor and air temperature
2009
[1] Land surface temperature (LST) is involved in many land surface processes such as evapotranspiration, net radiation, or air temperature modeling. In this paper we present an improved methodology to retrieve LST from Landsat 4 TM, Landsat 5 TM, and Landsat 7 ETM+ using four atmospheric databases covering different water vapor ranges (from 0 to 8 g cm−2) to build the LST retrieval models and using both water vapor and air temperature as input variables. We also compare this with LST retrievals using only water vapor or only air temperature, as well as with an existing LST retrieval algorithm. In order to validate the results, we have selected 77 Landsat images taken between 2002 and 2006 …
Analysis of Desert Dust Outbreaks Over Southern Europe Using CALIOP Data and Ground-Based Measurements
2016
Saharan dust outbreaks are one of the major aerosol sources in Southern Europe. Dust affects the radiative balance of the Earth–atmosphere system and impacts health. The assessment of Saharan outbreaks requires information about the vertical distribution of dust in the atmosphere, usually obtained from lidar measurements, such as the ones performed by the spaceborne Cloud-Aerosol Lidar with Orthogonal Polarization (CALIOP) sensor. In this paper, we have used CALIOP level-1 daytime data in combination with aerosol optical depth (AOD) measurements from Aerosol Robotic Network (AERONET) ground-based photometers to obtain aerosol profiles during 23 dust outbreaks over Southern Europe. These pro…
Hierarchical structure of the Sicilian goats revealed by Bayesian analyses of microsatellite information
2011
Summary Genetic structure and relationship amongst the main goat populations in Sicily (Girgentana, Derivata di Siria, Maltese and Messinese) were analysed using information from 19 microsatellite markers genotyped on 173 individuals. A posterior Bayesian approach implemented in the program STRUCTURE revealed a hierarchical structure with two clusters at the first level (Girgentana vs. Messinese, Derivata di Siria and Maltese), explaining 4.8% of variation (AMOVA UST estimate). Seven clusters nested within these first two clusters (further differentiations of Girgentana, Derivata di Siria and Maltese), explaining 8.5% of variation (AMOVA USC estimate). The analyses and methods applied in th…
Genetic variability of the blue and red shrimp Aristeus antennatus in the Western Mediterranean Sea inferred by DNA microsatellite loci
2011
Genetic variation at eight microsatellite loci was studied in nine populations of the blue and red shrimp Aristeus antennatus to investigate whether distinct stocks are present in the Western Mediterranean Sea. A high level of gene flow and no evidence of genetic partitioning were discovered. No significant variation was found (FST = 0.00673, P-value = 0.067) even when shrimps from exploited and those from deep-water unexploited grounds were compared. No evidence of reduction or expansion of population size in the recent past was found, as indicated by the bottleneck and interlocus g-tests. Our results are consistent with previous studies using mitochondrial gene methods and allozymes, indi…
Microsatellite DNA markers for two endemic ground beetles: Carabus punctatoauratus and C. solieri
2002
We isolated and characterized nine and five polymorphic microsatellite loci in the respective ground beetles Carabus punctatoauratus and C. solieri. We tested cross-species amplification of all these loci plus six isolated in C. solieri and for which primers sequences were soon published. From these combined analyses, we obtained 14 and 17 polymorphic markers, respectively, for C. punctatoauratus and C. solieri.
The quality of life of residents of a satellite degraded city district as part of urban development policy
2017
The purpose of this article is to assess the quality of life of the residents of a degraded satellite area of a city. It is considered in the context of urban development policy – as the result of decisions and as a challenge for long-term development. The research was based on a case study, which is the district of Opole referred to as Metalchem. It is characterized by an isolated location in the city structure as well as economic transformations. The study was based primarily on an analysis of source materials and results of a survey. The results show that the assessment of the quality of life is inconsistent. The living conditions are good, but satisfactory fulfilment of social needs is …
Drought Monitoring In The Mediterranean Basin Using The Seviri/Msg Gpp Product (Mgpp)
2020
Recently, the Satellite Application Facility for Land Surface Analysis (LSA-SAF) has just released a new product that helps to characterize ecosystem processes, the 10-day LSA SAF GPP product from SEVIRI/MSG data (MGPP LSA-411). The GPP product is based on Monteith's concept, which models GPP as the product of the incoming photosynthetically active radiation (PAR), the fractional absorption of that flux $(\mathrm{f}_{APAR})$ and a light-use efficiency factor $(\varepsilon)$. Preliminary results on the use of the MGPP product in the assessment of ecosystem response to drought events are presented in this work for a short period of three years. A few sites located in the Mediterranean basin a…
Improvement of the thermal emissivity calculated with the vegetation cover method by using optical atmospherically corrected images
2007
In this paper we assess the influence caused by the lack of atmospheric correction of the optical images used to calculate land surface emissivity (LSE). When thermal emissivity is determined by the Vegetation Cover Method (VCM), information from the solar spectrum in order to calculate the vegetation cover fraction is required. The atmospheric correction is performed in this research by using the combination of the Dark Dense Vegetation method (DDV) and the Second Simulation of the Satellite Signal in the Solar Spectrum (6S) code. The methodology was applied to a Landsat TM image of Tomelloso, Spain. It was determined that the emissivity between 10 and 12 mum only increases 0.4% (which rep…
Modular, customisable, accomodation-friendly antenna system for satellite avionics: Development, prototyping and validation
2014
In the frame of ESA program AO/1- 6737/11/NL/MH, an innovative X-band antenna system for satellite avionics has been studied, demonstrated and validated at Proof of Concept Model level. The innovative contribution of such an antenna system relies on modularity, customizability and accommodation friendliness. The antenna concept is based on a Plug and Play architecture, where the basic module is a 2.7 cm-cube with a mass of 53 gr, which can be clustered in array configuration. A catalogue of predefined and ready-to-use clusters could be developed with the possibility of adapting the antenna systems to various platform types by tuning just a few control parameters. Different levels of customi…