Search results for "LAI"
showing 10 items of 6640 documents
Mūzikas platformas "Spotify" lietojuma motivācija Latvijā
2019
Mūsdienās, attīstoties tehnoloģijām, palielinās pieprasījums pēc kvalitatīva ierīcēs pieejamā satura. Viedtālruņi, planšetdatori, personīgie datori - šīs ir tikai dažas ierīces, kuras patērējam ikdienā un bez kurām mūsdienu pasaule vairs nav iedomājama. Tradicionālo radio arvien straujāk nomaina digitālais radio un mūzikas lietotnes. Mūzikas platforma "Spotify" ir viena no lielākajām šāda tipa aplikācijām tirgū, kas 2019.gadā pārsniedz 200 miljonus aktīvo lietotāju visā pasaulē. Bakalaura darba "Mūzikas platformas "Spotify" lietojuma motivācija Latvijā" mērķis ir noskaidrot, kāpēc Latvijas iedzīvotāji dažādās vecuma grupās izvēlas patērēt šo mūzikas platformu, nevis kādu citu līdzīgu digita…
Pirkstiņrotaļas un rotaļas ar priekšmetiem 3- 4 gadus vecu bērnu griešanas prasmes sekmēšanai
2019
Kvalifikācijas darba tēma ir, “Pirkstiņrotaļas un rotaļas ar priekšmetiem 3-4 gadus vecu bērnu griešanas prasmes sekmēšanai”. Darba mērķis ir teorētiski analizēt un praktiski pētīt, kā pirkstiņrotaļu un rotaļu ar priekšmetiem pielietošana sekmē 3-4 gadus vecu bērnu griešanas prasmes. Mērķa sasniegšanai tika izvirzīti vairāki uzdevumi: 1. Analizēt pedagogu un psihologu atziņas par 3-4 gadus vecu bērnu attīstību un raksturot griešanas prasmes. 2.Analizēt pedagogu atziņas par rotaļu, pirkstiņrotaļu pētījuma kontekstā. 3.Veikt pētījumu par griešanas prasmju sekmēšanu rotaļā. Darba pirmajā daļā teorētiski tiek analizēta pedagogu un psihologu atziņas par bērna attīstības īpatnībām vidējā pirmskol…
A new 18 GHz room temperature electron cyclotron resonance ion source for highly charged ion beams
2020
An innovative 18 GHz HIISI (Heavy Ion Ion Source Injector) room temperature Electron Cyclotron Resonance (ECR) ion source (ECRIS) has been designed and constructed at the Department of Physics, University of Jyväskylä (JYFL), for the nuclear physics program of the JYFL Accelerator Laboratory. The primary objective of HIISI is to increase the intensities of medium charge states (M/Q ≅ 5) by a factor of 10 in comparison with the JYFL 14 GHz ECRIS and to increase the maximum usable xenon charge state from 35+ to 44+ to serve the space electronics irradiation testing program. HIISI is equipped with a refrigerated permanent magnet hexapole and a noncylindrical plasma chamber to achieve very stro…
Charge breeding at GANIL: Improvements, results, and comparison with the other facilities
2019
International audience; The 1+/n+ method, based on an ECRIS charge breeder (CB) originally developed at the LPSC laboratory, is now implemented at GANIL for the production of Radioactive Ion Beams (RIBs). Prior to its installation in the middle of the low energy beam line of the SPIRAL1 facility, the 1+/n+ system CB has been modified based on the experiments performed on the CARIBU Facility at Argone National Laboratory. Later, it has been tested at the 1+/n+ LPSC test bench to validate its operation performances. Charge breeding efficiencies as well as charge breeding times have been measured for noble gases and alkali elements. The commissioning phase started at GANIL in the second half-y…
Mapping Vegetation Density in a Heterogeneous River Floodplain Ecosystem Using Pointable CHRIS/PROBA Data
2012
River floodplains in the Netherlands serve as water storage areas, while they also have the function of nature rehabilitation areas. Floodplain vegetation is therefore subject to natural processes of vegetation succession. At the same time, vegetation encroachment obstructs the water flow into the floodplains and increases the flood risk for the hinterland. Spaceborne pointable imaging spectroscopy has the potential to quantify vegetation density on the basis of leaf area index (LAI) from a desired view zenith angle. In this respect, hyperspectral pointable CHRIS data were linked to the ray tracing canopy reflectance model FLIGHT to retrieve vegetation density estimates over a heterogeneous…
Exploitation of SAR and Optical Sentinel Data to Detect Rice Crop and Estimate Seasonal Dynamics of Leaf Area Index
2017
This paper presents and evaluates multitemporal LAI estimates derived from Sentinel-2A data on rice cultivated area identified using time series of Sentinel-1A images over the main European rice districts for the 2016 crop season. This study combines the information conveyed by Sentinel-1A and Sentinel-2A into a high-resolution LAI retrieval chain. Rice crop was detected using an operational multi-temporal rule-based algorithm, and LAI estimates were obtained by inverting the PROSAIL radiative transfer model with Gaussian process regression. Direct validation was performed with in situ LAI measurements acquired in coordinated field campaigns in three countries (Italy, Spain and Greece). Res…
The 2009 Edition of the GEISA Spectroscopic Database
2011
The updated 2009 edition of the spectroscopic database GEISA (Gestion et Etude des Informations Spectroscopiques Atmosphériques; Management and Study of Atmospheric Spectroscopic Information) is described in this paper. GEISA is a computer-accessible system comprising three independent sub-databases devoted, respectively, to: line parameters, infrared and ultraviolet/visible absorption cross-sections, microphysical and optical properties of atmospheric aerosols. In this edition, 50 molecules are involved in the line parameters sub-database, including 111 isotopologues, for a total of 3,807,997 entries, in the spectral range from 10-6 to 35,877.031cm-1.The successful performances of the new …
A multisensor fusion approach to improve LAI time series
2011
International audience; High-quality and gap-free satellite time series are required for reliable terrestrial monitoring. Moderate resolution sensors provide continuous observations at global scale for monitoring spatial and temporal variations of land surface characteristics. However, the full potential of remote sensing systems is often hampered by poor quality or missing data caused by clouds, aerosols, snow cover, algorithms and instrumentation problems. A multisensor fusion approach is here proposed to improve the spatio-temporal continuity, consistency and accuracy of current satellite products. It is based on the use of neural networks, gap filling and temporal smoothing techniques. …
Influencia del ángulo de observación en la estimación del índice de área foliar (LAI) mediante imágenes PROBA/CHRIS
2016
La estimación de variables biofísicas como el Índice de Área Foliar (LAI) mediante técnicas de teledetección es objeto de numerosos estudios, ya que de su conocimiento se puede extraer valiosa información sobre el estado de la vegetación. En este trabajo se estudia la estimación del LAI mediante imágenes multiangulares PROBA/CHRIS, analizando el comportamiento de la reflectividad medida en sus 5 ángulos de observación, en las longitudes de onda de 665 y 705 nm correspondientes a la banda de absorción de la clorofila y la reflectividad de la vegetación en el Red-Edge, respectivamente. El Índice de Diferencia Normalizada (NDI) calculado en estas longitudes de onda, mostró una buena correlació…
The response of flood-plain ecosystems to the Late Glacial and Early Holocene hydrological changes: A case study from a small Central European river …
2016
Abstract We use a range of environmental variables to explore the possible drivers influencing the biota, especially the composition of aquatic invertebrates, during the Younger Dryas (YD) and Early Holocene (EH) in different river valley sites: a well-developed meandering river and the confluence zone of headwater streams. Using pollen, macrofossil, cladoceran, and chironomid as well as geochemical and lithological data as proxies for environmental factors (i.e., water depth and temperature), we attempt to show that these different sites display similar hydroclimatic signals (especially floods). The geochemical records in the studied valley are correlated with environmental factors, such a…