@prefix dcat: <http://www.w3.org/ns/dcat#> .
@prefix dct: <http://purl.org/dc/terms/> .
@prefix foaf: <http://xmlns.com/foaf/0.1/> .
@prefix vcard: <http://www.w3.org/2006/vcard/ns#> .
@prefix xsd: <http://www.w3.org/2001/XMLSchema#> .

<https://rec.harvest-normandie.data4citizen.com/dataset/oai-hal-tel-00802430v1> a dcat:Dataset ;
    dct:description """
              This thesis presents results based on wave measurements performed by the DEMETER spacecraft. This French spacecraft was operating between 2004 and 2010 at the altitude of ~660 km. We focus on measurements of the electromagnetic waves and plasma density in the vicinity of imminent earthquakes. In a first part, we present a study of plasma density variations in the vicinity of a very powerful earthquake in Chile ( Mω 8.8) which occurred on February 27, 2010. Data recorded before the main shock along orbits close to the future epicenter showed increasing plasma densities. In a second step, a statistical analysis using 4 years of data to monitor density variations under similar conditions has been performed. This study shows that a large increase of the plasma density is very uncommon at this location and at this time. In a second part, a statistical study (~6.5 years) of variations of VLF wave intensity is shown. We have analyzed all available data measured close (in time and in distance) to large earthquakes (M> ou = 5). Data related to more than 12000 earthquakes have been compared with an unperturbed background distribution. We confirm the previously reported results of a statistically significant decrease of the wave intensity at frequencies of about ~1.7kHz. This effect seems to be related to a decrease of the lower ionospheric boundary which affects the VLF waves propagating in the Earth-ionosphere waveguide.
            """ ;
    dct:identifier "NNT: 2012ORLE2034" ;
    dct:issued "2026-05-12T06:52:48.706191"^^xsd:dateTime ;
    dct:language "fr" ;
    dct:modified "2026-05-12T06:52:48.706197"^^xsd:dateTime ;
    dct:publisher <https://rec.harvest-normandie.data4citizen.com/organization/cce9db95-46d9-4dc2-84b6-764215d0a002> ;
    dct:title "Study of electromagntic emissions recorded by the DEMETER satellite" ;
    dcat:contactPoint [ a vcard:Organization ;
            vcard:fn "CCSD" ] ;
    dcat:distribution <https://rec.harvest-normandie.data4citizen.com/dataset/oai-hal-tel-00802430v1/resource/b8e04ebe-e879-4a1b-a5c0-4d100dd89968> ;
    dcat:keyword "demeter",
        "earthquakes",
        "electromagnetic-waves",
        "infoeu-reposemanticsdoctoralthesis",
        "ondes-electromagnetiques",
        "physcondcm-genphysics-physicscondensed-matter-cond-matother-cond-matother",
        "plasma-spatial",
        "space-plasma",
        "theses",
        "tremblements-de-terre" ;
    dcat:landingPage <https://theses.hal.science/tel-00802430> .

<https://rec.harvest-normandie.data4citizen.com/dataset/oai-hal-tel-00802430v1/resource/b8e04ebe-e879-4a1b-a5c0-4d100dd89968> a dcat:Distribution ;
    dct:format "HTML" ;
    dct:issued "2026-05-12T06:52:48.756852"^^xsd:dateTime ;
    dct:modified "2026-05-12T06:52:48.672657"^^xsd:dateTime ;
    dct:title "Study of electromagntic emissions recorded by the DEMETER satellite" ;
    dcat:accessURL <https://theses.hal.science/tel-00802430> .

<https://rec.harvest-normandie.data4citizen.com/organization/cce9db95-46d9-4dc2-84b6-764215d0a002> a foaf:Agent ;
    foaf:name "test_moissonnage_selune" .

<https://theses.hal.science/tel-00802430> a foaf:Document .