{"@context":{"@vocab":"https://cir.nii.ac.jp/schema/1.0/","rdfs":"http://www.w3.org/2000/01/rdf-schema#","dc":"http://purl.org/dc/elements/1.1/","dcterms":"http://purl.org/dc/terms/","foaf":"http://xmlns.com/foaf/0.1/","prism":"http://prismstandard.org/namespaces/basic/2.0/","cinii":"http://ci.nii.ac.jp/ns/1.0/","datacite":"https://schema.datacite.org/meta/kernel-4/","ndl":"http://ndl.go.jp/dcndl/terms/","jpcoar":"https://github.com/JPCOAR/schema/blob/master/2.0/"},"@id":"https://cir.nii.ac.jp/crid/1360004233291930496.json","@type":"Article","productIdentifier":[{"identifier":{"@type":"DOI","@value":"10.1029/2018ja025491"}},{"identifier":{"@type":"URI","@value":"https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1029%2F2018JA025491"}},{"identifier":{"@type":"URI","@value":"https://agupubs.onlinelibrary.wiley.com/doi/pdf/10.1029/2018JA025491"}}],"resourceType":"学術雑誌論文(journal article)","dc:title":[{"@value":"On the Solstice Maxima and Azimuth‐Dependent Characteristics of the 150‐km Echoes Observed Using the Equatorial Atmosphere Radar"}],"description":[{"type":"abstract","notation":[{"@value":"<jats:title>Abstract</jats:title><jats:p>We present long overdue statistical analysis of the 150‐km echoes based on 10 years of observations made using the Equatorial Atmosphere Radar located at Kototabang, Indonesia. Analysis shows that while the basic features of the echoes are very similar to those observed from other equatorial/low‐latitude stations, occurrence and power/signal‐to‐noise ratio of the echoes are much higher in the solstices than in the equinoxes. Furthermore, both occurrence rate and power/signal‐to‐noise ratio of the echoes in the December solstice are marginally lower than those of the June solstice. The observed solstice‐equinox asymmetry has important implications with regard to the generation mechanism of the 150‐km echoes since this seasonal behavior cannot be accounted for by the recently proposed photoelectron‐induced enhanced plasma wave process alone. Equatorial Atmosphere Radar observations also display remarkable azimuthal variations of the echo characteristics, which indicate magnetic aspect angle dependence of the echoes. The implications of these results are discussed in terms of the origin of the 150‐km echoes.</jats:p>"}]}],"creator":[{"@id":"https://cir.nii.ac.jp/crid/1380004233291930499","@type":"Researcher","foaf:name":[{"@value":"P. Pavan Chaitanya"}],"jpcoar:affiliationName":[{"@value":"National Atmospheric Research Laboratory  Gadanki India"}]},{"@id":"https://cir.nii.ac.jp/crid/1380004233291930382","@type":"Researcher","foaf:name":[{"@value":"A. K. Patra"}],"jpcoar:affiliationName":[{"@value":"National Atmospheric Research Laboratory  Gadanki India"}]},{"@id":"https://cir.nii.ac.jp/crid/1380004233291930379","@type":"Researcher","foaf:name":[{"@value":"Y. Otsuka"}],"jpcoar:affiliationName":[{"@value":"Institute for Space‐Earth Environmental Research Nagoya University  Nagoya Japan"}]},{"@id":"https://cir.nii.ac.jp/crid/1380004233291930498","@type":"Researcher","foaf:name":[{"@value":"T. Yokoyama"}],"jpcoar:affiliationName":[{"@value":"National Institute of Information and Communication Technology  Tokyo Japan"}]},{"@id":"https://cir.nii.ac.jp/crid/1380004233291930378","@type":"Researcher","foaf:name":[{"@value":"M. Yamamoto"}],"jpcoar:affiliationName":[{"@value":"Research Institute for Sustainable Humanosphere Kyoto University  Uji Japan"}]}],"publication":{"publicationIdentifier":[{"@type":"PISSN","@value":"21699380"},{"@type":"EISSN","@value":"21699402"}],"prism:publicationName":[{"@value":"Journal of Geophysical Research: Space Physics"}],"dc:publisher":[{"@value":"American Geophysical Union (AGU)"}],"prism:publicationDate":"2018-08","prism:volume":"123","prism:number":"8","prism:startingPage":"6752","prism:endingPage":"6759"},"reviewed":"false","dc:rights":["http://onlinelibrary.wiley.com/termsAndConditions#vor"],"url":[{"@id":"https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1029%2F2018JA025491"},{"@id":"https://agupubs.onlinelibrary.wiley.com/doi/pdf/10.1029/2018JA025491"}],"createdAt":"2018-07-23","modifiedAt":"2025-07-24","project":[{"@id":"https://cir.nii.ac.jp/crid/1040282256801950080","@type":"Project","projectIdentifier":[{"@type":"KAKEN","@value":"15H02135"},{"@type":"JGN","@value":"JP15H02135"},{"@type":"URI","@value":"https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-15H02135/"}],"notation":[{"@language":"ja","@value":"新・衛星＝地上ビーコン観測と赤道大気レーダーによる低緯度電離圏の時空間変動の解明"},{"@language":"en","@value":"Study of spatio-temporal fluctuation of low latitude ionosphere by using new satellite-ground beacon observation and Equatorial Atmospheric 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