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[{"key": "dc.contributor.advisor", "value": "Kainulainen, Kimmo", "language": "", "element": "contributor", "qualifier": "advisor", "schema": "dc"}, {"key": "dc.contributor.advisor", "value": "Timonen, Jussi", "language": "", "element": "contributor", "qualifier": "advisor", "schema": "dc"}, {"key": "dc.contributor.author", "value": "Eskelinen, Matti Aleksanteri", "language": null, "element": "contributor", "qualifier": "author", "schema": "dc"}, {"key": "dc.date.accessioned", "value": "2015-07-01T13:39:58Z", "language": "", "element": "date", "qualifier": "accessioned", "schema": "dc"}, {"key": "dc.date.available", "value": "2015-07-01T13:39:58Z", "language": "", "element": "date", "qualifier": "available", "schema": "dc"}, {"key": "dc.date.issued", "value": "2015", "language": null, "element": "date", "qualifier": "issued", "schema": "dc"}, {"key": "dc.identifier.other", "value": "oai:jykdok.linneanet.fi:1477043", "language": null, "element": "identifier", "qualifier": "other", "schema": "dc"}, {"key": "dc.identifier.uri", "value": "https://jyx.jyu.fi/handle/123456789/46451", "language": "", "element": "identifier", "qualifier": "uri", "schema": "dc"}, {"key": "dc.description.abstract", "value": "Massiivisten galaksien gravitaatio aiheuttaa v\u00e4\u00e4ristym\u00e4n teleskoopilla\r\nhavaittavaan kuvaan muuttamalla galaksin takaa saapuvan valon reitti\u00e4. Niin kutsu-\r\ntuissa vahvoissa gravitaatiolinsseiss\u00e4 voi linssin\u00e4 toimiva galaksi tuottaa kuvaan sen\r\ntakana olevasta galaksista useita n\u00e4ytt\u00e4vi\u00e4 kaaria. Linssin\u00e4 toimineen galaksin massa\r\nja linssiytyneen galaksin alkuper\u00e4inen muoto voidaan t\u00e4ll\u00f6in laskennallisesti selvit-\r\nt\u00e4\u00e4, ja n\u00e4in saada tietoa linssigalaksin massan ja teleskoopilla suoraan havaitun valon\r\nm\u00e4\u00e4r\u00e4n suhteesta. T\u00e4m\u00e4n l\u00e4ht\u00f6kohtaisesti huonosti m\u00e4\u00e4ritellyn inversio-ongelman\r\nlaskennallinen ratkaiseminen vaatii kuitenkin ongelman uudelleenm\u00e4\u00e4rittely\u00e4 eli\r\nregularisaatiota. Ongelman ratkaisemiseen kehitetyt menetelm\u00e4t perustuvat yleens\u00e4\r\nep\u00e4lineaariseen optimointiin ja hy\u00f6dynt\u00e4v\u00e4t toisistaan eroavia regularisaatiostra-\r\ntegioita. T\u00e4ss\u00e4 ty\u00f6ss\u00e4 tutkin simuloitujen galaksien avulla, suosivatko Tikhonov-,\r\nkokonaisvariaatio- ja maksimientropiaregularisaatio tietynlaisia ratkaisuja. Ty\u00f6t\u00e4\r\nvarten toteutin simulointiin soveltuvan ohjelmistokokonaisuuden k\u00e4ytt\u00e4en numeriik-\r\nkaan harvemmin k\u00e4ytetty\u00e4 Haskell-ohjelmointikielt\u00e4. Tehdyt simulaatiot vahvistavat\r\naiemmin tunnetun sileytt\u00e4 optimoivien regularisaatiomenetelmien k\u00e4yt\u00f6ksen, joka\r\nsuosii yleisesti matalan keskeiskonsentraation omaavia galakseja. Regularisaatio-\r\nmenetelmien v\u00e4lill\u00e4 ei havaittu merkitt\u00e4vi\u00e4 eroja tutkituissa parametriavaruuksien\r\nosissa k\u00e4ytetyill\u00e4 keskeissymmetrisill\u00e4 galaksimalleilla.", "language": "fi", "element": "description", "qualifier": "abstract", "schema": "dc"}, {"key": "dc.description.abstract", "value": "The gravitation of massive galaxies causes a distortion of the images\r\ndetected by telescopes by deflecting the light passing by the galaxy. So called strong\r\ngravitational lenses can cause a single background galaxy to appear as multiple arcs\r\nin the image. When this happens, the mass of the lens galaxy and the original shape\r\nof the background galaxy may be computed numerically, allowing information of\r\nthe mass-to-light ratio of the lens galaxy to be inferred using the telescope data of the\r\nluminosity of the galaxy. However, this inverse problem is ill-posed, and needs to be\r\nmade well-posed i.e. regularized in order to find a solution. The methods developed\r\nfor the problem are usually based on nonlinear optimization and employ different\r\nregularization strategies. In this work I study the possible biases of Tikhonov, total\r\nvariation and maximum entropy methods using simulated galaxies. For the work\r\nI implemented a software compilation capable of simulating the galaxies using\r\nthe Haskell programming language, which is rarely used in numerical work. The\r\nsimulations confirm the known smoothing effect of the regularizations, which\r\ncauses them to prefer less centrally concentrated galaxies. No significant differences\r\nbetween the regularizations were observed in the parameter spaces of the studied\r\ncentrally symmetric galaxy models.", "language": "en", "element": "description", "qualifier": "abstract", "schema": "dc"}, {"key": "dc.description.provenance", "value": "Submitted using Plone Publishing form by Matti Eskelinen (maaleske) on 2015-07-01 13:39:57.709989. Form: Pro gradu -lomake (https://kirjasto.jyu.fi/julkaisut/julkaisulomakkeet/pro-gradu-lomake). JyX data: [jyx_publishing-allowed (fi) =True]", "language": "en", "element": "description", "qualifier": "provenance", "schema": "dc"}, {"key": "dc.description.provenance", "value": "Submitted by jyx lomake-julkaisija (jyx-julkaisija.group@korppi.jyu.fi) on 2015-07-01T13:39:58Z\r\nNo. of bitstreams: 2\r\nURN:NBN:fi:jyu-201507012493.pdf: 5492078 bytes, checksum: 1e94001b5684508bab8c364151de2244 (MD5)\r\nlicense.html: 4814 bytes, checksum: 45189ba290f66577e4f6c019d0d336a9 (MD5)", "language": "en", "element": "description", "qualifier": "provenance", "schema": "dc"}, {"key": "dc.description.provenance", "value": "Made available in DSpace on 2015-07-01T13:39:58Z (GMT). No. of bitstreams: 2\r\nURN:NBN:fi:jyu-201507012493.pdf: 5492078 bytes, checksum: 1e94001b5684508bab8c364151de2244 (MD5)\r\nlicense.html: 4814 bytes, checksum: 45189ba290f66577e4f6c019d0d336a9 (MD5)\r\n Previous issue date: 2015", "language": "en", "element": "description", "qualifier": "provenance", "schema": "dc"}, {"key": "dc.format.extent", "value": "1 verkkoaineisto (71 sivua)", "language": null, "element": "format", "qualifier": "extent", "schema": "dc"}, {"key": "dc.format.mimetype", "value": "application/pdf", "language": null, "element": "format", "qualifier": "mimetype", "schema": "dc"}, {"key": "dc.language.iso", "value": "fin", "language": null, "element": "language", "qualifier": "iso", "schema": "dc"}, {"key": "dc.rights", "value": "In Copyright", "language": "en", "element": "rights", "qualifier": null, "schema": "dc"}, {"key": "dc.subject.other", "value": "regularisaatio", "language": null, "element": "subject", "qualifier": "other", "schema": "dc"}, {"key": "dc.subject.other", "value": "gravitaatiolinssi", "language": null, "element": "subject", "qualifier": "other", "schema": "dc"}, {"key": "dc.subject.other", "value": "Haskell", "language": null, "element": "subject", "qualifier": "other", "schema": "dc"}, {"key": "dc.title", "value": "Regularisaatio vahvojen gravitaatiolinssien inversiossa", "language": null, "element": "title", "qualifier": null, "schema": "dc"}, {"key": "dc.type", "value": "master thesis", "language": null, "element": "type", "qualifier": null, "schema": "dc"}, {"key": "dc.identifier.urn", "value": "URN:NBN:fi:jyu-201507012493", "language": null, "element": "identifier", "qualifier": "urn", "schema": "dc"}, {"key": "dc.type.ontasot", "value": "Pro gradu -tutkielma", "language": "fi", "element": "type", "qualifier": "ontasot", "schema": "dc"}, {"key": "dc.type.ontasot", "value": "Master\u2019s thesis", "language": "en", "element": "type", "qualifier": "ontasot", "schema": "dc"}, {"key": "dc.contributor.faculty", "value": "Matemaattis-luonnontieteellinen tiedekunta", "language": "fi", "element": "contributor", "qualifier": "faculty", "schema": "dc"}, {"key": "dc.contributor.faculty", "value": "Faculty of Sciences", "language": "en", "element": "contributor", "qualifier": "faculty", "schema": "dc"}, {"key": "dc.contributor.department", "value": "Fysiikan laitos", "language": "fi", "element": "contributor", "qualifier": "department", "schema": "dc"}, {"key": "dc.contributor.department", "value": "Department of Physics", "language": "en", "element": "contributor", "qualifier": "department", "schema": "dc"}, {"key": "dc.contributor.organization", "value": "University of Jyv\u00e4skyl\u00e4", "language": "en", "element": "contributor", "qualifier": "organization", "schema": "dc"}, {"key": "dc.contributor.organization", "value": "Jyv\u00e4skyl\u00e4n yliopisto", "language": "fi", "element": "contributor", "qualifier": "organization", "schema": "dc"}, {"key": "dc.subject.discipline", "value": "Teoreettinen fysiikka", "language": "fi", "element": "subject", "qualifier": "discipline", "schema": "dc"}, {"key": "dc.subject.discipline", "value": "Theoretical Physics", "language": "en", "element": "subject", "qualifier": "discipline", "schema": "dc"}, {"key": "dc.date.updated", "value": "2015-07-01T13:39:59Z", "language": "", "element": "date", "qualifier": "updated", "schema": "dc"}, {"key": "yvv.contractresearch.funding", "value": "0", "language": "", "element": "contractresearch", "qualifier": "funding", "schema": "yvv"}, {"key": "dc.type.coar", "value": "http://purl.org/coar/resource_type/c_bdcc", "language": null, "element": "type", "qualifier": "coar", "schema": "dc"}, {"key": "dc.rights.accesslevel", "value": "openAccess", "language": "fi", "element": "rights", "qualifier": "accesslevel", "schema": "dc"}, {"key": "dc.type.publication", "value": "masterThesis", "language": null, "element": "type", "qualifier": "publication", "schema": "dc"}, {"key": "dc.subject.oppiainekoodi", "value": "4024", "language": null, "element": "subject", "qualifier": "oppiainekoodi", "schema": "dc"}, {"key": "dc.subject.yso", "value": "gravitaatio", "language": null, "element": "subject", "qualifier": "yso", "schema": "dc"}, {"key": "dc.subject.yso", "value": "inversio-ongelmat", "language": null, "element": "subject", "qualifier": "yso", "schema": "dc"}, {"key": "dc.format.content", "value": "fulltext", "language": null, "element": "format", "qualifier": "content", "schema": "dc"}, {"key": "dc.rights.url", "value": "https://rightsstatements.org/page/InC/1.0/", "language": null, "element": "rights", "qualifier": "url", "schema": "dc"}, {"key": "dc.type.okm", "value": "G2", "language": null, "element": "type", "qualifier": "okm", "schema": "dc"}]
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