{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T01:43:36Z","timestamp":1760233416020,"version":"build-2065373602"},"reference-count":20,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2021,1,15]],"date-time":"2021-01-15T00:00:00Z","timestamp":1610668800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Symmetry"],"abstract":"<jats:p>This article investigates the spectral theory of the problem of the Regge-type with transmission conditions and discontinuous coefficients. We formulate a new linear operator, by which we can deal with simplicity and boundedness of the eigenpairs of the problem. The aim of this work is to conduct that the problem has an infinite number of simple positive eigenvalues.<\/jats:p>","DOI":"10.3390\/sym13010139","type":"journal-article","created":{"date-parts":[[2021,1,21]],"date-time":"2021-01-21T02:36:05Z","timestamp":1611196565000},"page":"139","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Behavior of the Eigenvalues and Eignfunctions of the Regge-Type Problem"],"prefix":"10.3390","volume":"13","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-4009-0357","authenticated-orcid":false,"given":"Karwan H. F.","family":"Jwamer","sequence":"first","affiliation":[{"name":"Mathematics Department, College of Science, University of Sulaimani, Sulaimani 46001, Kurdistan Region, Iraq"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0057-3020","authenticated-orcid":false,"given":"Rando R. Q.","family":"Rasul","sequence":"additional","affiliation":[{"name":"Department of Mathematical Sciences, College of Basic Education, University of Sulaimani, Sulaimani 46001, Kurdistan Region, Iraq"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2021,1,15]]},"reference":[{"unstructured":"Naimark, M.A. (1967). Linear Differential Operators Part 1: Elementary Theory of Linear Differential Operators, Frederick Ungar Publishing.","key":"ref_1"},{"doi-asserted-by":"crossref","unstructured":"Kerimov, N.B., and Mamedov, K.R. (1998). On the Riesz Basis Property of the Root Functions in Certain Regular Boundary Value Problems, Springer. Mathematical Notes.","key":"ref_2","DOI":"10.1007\/BF02314629"},{"doi-asserted-by":"crossref","unstructured":"Regge, T. (1958). 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Accurate approximate Formulas for eigen-pairs of a Boundary-Value Problem of Fourth Order. Bound. Value Probl., 720235.","key":"ref_20","DOI":"10.1155\/2010\/720235"}],"container-title":["Symmetry"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2073-8994\/13\/1\/139\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T05:11:49Z","timestamp":1760159509000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2073-8994\/13\/1\/139"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2021,1,15]]},"references-count":20,"journal-issue":{"issue":"1","published-online":{"date-parts":[[2021,1]]}},"alternative-id":["sym13010139"],"URL":"https:\/\/doi.org\/10.3390\/sym13010139","relation":{},"ISSN":["2073-8994"],"issn-type":[{"type":"electronic","value":"2073-8994"}],"subject":[],"published":{"date-parts":[[2021,1,15]]}}}