{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,14]],"date-time":"2026-05-14T00:29:44Z","timestamp":1778718584352,"version":"3.51.4"},"reference-count":30,"publisher":"Walter de Gruyter GmbH","issue":"1","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"published-print":{"date-parts":[[2018,1,1]]},"abstract":"<jats:title>Abstract<\/jats:title>\n               <jats:p>We present and analyze a space-time Petrov\u2013Galerkin finite element method for a time-fractional diffusion equation\ninvolving a Riemann\u2013Liouville fractional derivative of order <jats:inline-formula id=\"j_cmam-2017-0026_ineq_9999_w2aab3b7d487b1b6b1aab1c14b1b1Aa\">\n                     <jats:alternatives>\n                        <m:math xmlns:m=\"http:\/\/www.w3.org\/1998\/Math\/MathML\">\n                           <m:mrow>\n                              <m:mi>\u03b1<\/m:mi>\n                              <m:mo>\u2208<\/m:mo>\n                              <m:mrow>\n                                 <m:mo stretchy=\"false\">(<\/m:mo>\n                                 <m:mn>0<\/m:mn>\n                                 <m:mo>,<\/m:mo>\n                                 <m:mn>1<\/m:mn>\n                                 <m:mo stretchy=\"false\">)<\/m:mo>\n                              <\/m:mrow>\n                           <\/m:mrow>\n                        <\/m:math>\n                        <jats:inline-graphic xmlns:xlink=\"http:\/\/www.w3.org\/1999\/xlink\" xlink:href=\"graphic\/j_cmam-2017-0026_eq_mi594.png\"\/>\n                        <jats:tex-math>{\\alpha\\in(0,1)}<\/jats:tex-math>\n                     <\/jats:alternatives>\n                  <\/jats:inline-formula> in time and zero initial data.\nWe derive a proper weak formulation involving different solution and test spaces and show the inf-sup condition for the bilinear form and thus its well-posedness.\nFurther, we develop a novel finite element formulation, show the well-posedness of the discrete problem, and\nderive error bounds in both energy and <jats:inline-formula id=\"j_cmam-2017-0026_ineq_9998_w2aab3b7d487b1b6b1aab1c14b1b3Aa\">\n                     <jats:alternatives>\n                        <m:math xmlns:m=\"http:\/\/www.w3.org\/1998\/Math\/MathML\">\n                           <m:msup>\n                              <m:mi>L<\/m:mi>\n                              <m:mn>2<\/m:mn>\n                           <\/m:msup>\n                        <\/m:math>\n                        <jats:inline-graphic xmlns:xlink=\"http:\/\/www.w3.org\/1999\/xlink\" xlink:href=\"graphic\/j_cmam-2017-0026_eq_mi543.png\"\/>\n                        <jats:tex-math>{L^{2}}<\/jats:tex-math>\n                     <\/jats:alternatives>\n                  <\/jats:inline-formula> norms for the finite element solution. In the proof\nof the discrete inf-sup condition, a certain nonstandard <jats:inline-formula id=\"j_cmam-2017-0026_ineq_9997_w2aab3b7d487b1b6b1aab1c14b1b5Aa\">\n                     <jats:alternatives>\n                        <m:math xmlns:m=\"http:\/\/www.w3.org\/1998\/Math\/MathML\">\n                           <m:msup>\n                              <m:mi>L<\/m:mi>\n                              <m:mn>2<\/m:mn>\n                           <\/m:msup>\n                        <\/m:math>\n                        <jats:inline-graphic xmlns:xlink=\"http:\/\/www.w3.org\/1999\/xlink\" xlink:href=\"graphic\/j_cmam-2017-0026_eq_mi543.png\"\/>\n                        <jats:tex-math>{L^{2}}<\/jats:tex-math>\n                     <\/jats:alternatives>\n                  <\/jats:inline-formula> stability property of the <jats:inline-formula id=\"j_cmam-2017-0026_ineq_9996_w2aab3b7d487b1b6b1aab1c14b1b7Aa\">\n                     <jats:alternatives>\n                        <m:math xmlns:m=\"http:\/\/www.w3.org\/1998\/Math\/MathML\">\n                           <m:msup>\n                              <m:mi>L<\/m:mi>\n                              <m:mn>2<\/m:mn>\n                           <\/m:msup>\n                        <\/m:math>\n                        <jats:inline-graphic xmlns:xlink=\"http:\/\/www.w3.org\/1999\/xlink\" xlink:href=\"graphic\/j_cmam-2017-0026_eq_mi543.png\"\/>\n                        <jats:tex-math>{L^{2}}<\/jats:tex-math>\n                     <\/jats:alternatives>\n                  <\/jats:inline-formula> projection operator plays a key role.\nWe provide extensive numerical examples to verify the convergence analysis.<\/jats:p>","DOI":"10.1515\/cmam-2017-0026","type":"journal-article","created":{"date-parts":[[2017,8,26]],"date-time":"2017-08-26T10:00:40Z","timestamp":1503741640000},"page":"1-20","source":"Crossref","is-referenced-by-count":19,"title":["Space-Time Petrov\u2013Galerkin FEM for Fractional Diffusion Problems"],"prefix":"10.1515","volume":"18","author":[{"given":"Beiping","family":"Duan","sequence":"first","affiliation":[{"name":"School of Mathematics and Statistics , Central South University , 410083 Changsha , P. R. China ; and Department of Mathematics, Texas A&M University, College Station, TX 77843-3368, USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Bangti","family":"Jin","sequence":"additional","affiliation":[{"name":"Department of Computer Science , University College London , Gower Street , London WC1E 6BT , United Kingdom"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Raytcho","family":"Lazarov","sequence":"additional","affiliation":[{"name":"Department of Mathematics , Texas A&M University , College Station , TX 77843-3368 , USA ; and Institute of Mathematics and Informatics, Bulgarian Academy of Sciences, Acad. Georgi Bonchev Str., Block 8, 1113 Sofia, Bulgaria"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Joseph","family":"Pasciak","sequence":"additional","affiliation":[{"name":"Department of Mathematics , Texas A&M University , College Station , TX 77843-3368 , USA"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Zhi","family":"Zhou","sequence":"additional","affiliation":[{"name":"Department of Applied Mathematics , The Hong Kong Polytechnic University , Kowloon , Hong Kong , P. R. China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"374","published-online":{"date-parts":[[2017,8,26]]},"reference":[{"key":"2023033115122817085_j_cmam-2017-0026_ref_001_w2aab3b7d487b1b6b1ab2ab1Aa","doi-asserted-by":"crossref","unstructured":"O.  Axelsson and J.  Maubach,\nA time-space finite element discretization technique for the calculation of the electromagnetic field in ferromagnetic materials,\nInternat. J. Numer. Methods Engrg. 28 (1989), no. 9, 2085\u20132111.","DOI":"10.1002\/nme.1620280908"},{"key":"2023033115122817085_j_cmam-2017-0026_ref_002_w2aab3b7d487b1b6b1ab2ab2Aa","doi-asserted-by":"crossref","unstructured":"R. E.  Bank, P. S.  Vassilevski and L. T.  Zikatanov,\nArbitrary dimension convection-diffusion schemes for space-time discretizations,\nJ. Comput. Appl. Math. 310 (2017), 19\u201331.","DOI":"10.1016\/j.cam.2016.04.029"},{"key":"2023033115122817085_j_cmam-2017-0026_ref_003_w2aab3b7d487b1b6b1ab2ab3Aa","doi-asserted-by":"crossref","unstructured":"W.  Dahmen, B.  Faermann, I. G.  Graham, W.  Hackbusch and S. A.  Sauter,\nInverse inequalities on non-quasi-uniform meshes and application to the mortar element method,\nMath. Comp. 73 (2004), no. 247, 1107\u20131138.","DOI":"10.1090\/S0025-5718-03-01583-7"},{"key":"2023033115122817085_j_cmam-2017-0026_ref_004_w2aab3b7d487b1b6b1ab2ab4Aa","doi-asserted-by":"crossref","unstructured":"D. A.  Di Pietro and A.  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Engrg. 283 (2015), 1545\u20131569.","DOI":"10.1016\/j.cma.2014.10.051"}],"container-title":["Computational Methods in Applied Mathematics"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.degruyter.com\/view\/journals\/cmam\/18\/1\/article-p1.xml","content-type":"text\/html","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/www.degruyter.com\/document\/doi\/10.1515\/cmam-2017-0026\/xml","content-type":"application\/xml","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/www.degruyter.com\/document\/doi\/10.1515\/cmam-2017-0026\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2023,3,31]],"date-time":"2023-03-31T21:45:58Z","timestamp":1680299158000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.degruyter.com\/document\/doi\/10.1515\/cmam-2017-0026\/html"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2017,8,26]]},"references-count":30,"journal-issue":{"issue":"1","published-online":{"date-parts":[[2017,6,17]]},"published-print":{"date-parts":[[2018,1,1]]}},"alternative-id":["10.1515\/cmam-2017-0026"],"URL":"https:\/\/doi.org\/10.1515\/cmam-2017-0026","relation":{},"ISSN":["1609-9389","1609-4840"],"issn-type":[{"value":"1609-9389","type":"electronic"},{"value":"1609-4840","type":"print"}],"subject":[],"published":{"date-parts":[[2017,8,26]]}}}