{"id":3655,"date":"2014-11-20T11:32:52","date_gmt":"2014-11-20T07:32:52","guid":{"rendered":"http:\/\/www.imm.az\/exp\/?page_id=3655"},"modified":"2019-02-05T10:47:27","modified_gmt":"2019-02-05T06:47:27","slug":"ismayilov-vugar-elman","status":"publish","type":"page","link":"https:\/\/www.imm.az\/exp\/personnel\/ismayilov-vugar-elman\/","title":{"rendered":"Ismayilov Vugar Elman"},"content":{"rendered":"<p style=\"text-align: justify;\"><strong>Basic scientific achievements<\/strong><\/p>\n<p style=\"text-align: justify;\">1) Necessary and sufficient conditions for the representation of multivariate functions by linear combinations of ridge functions were obtained;<\/p>\n<p style=\"text-align: justify;\">2) A Chebyshev type theorem was proved for sums of ridge functions to be extremal to a given continuous function;<\/p>\n<p style=\"text-align: justify;\">3) Explicit formulas for an exact computation of the approximation error and construction of best approximating function were obtained in problems of approximation of multivariate functions by ridge functions and univariate functions in both continuous and square-integrable metrics;<\/p>\n<p style=\"text-align: justify;\">4) It was shown that if each continuous function defined on a compact Hausdorff space is represented by linear superpositions, then all functions on this space possess such representation;<\/p>\n<p style=\"text-align: justify;\">5) The problem of multivariate approximation theory associated with Golomb&#8217;s theorem was solved.<\/p>\n<p style=\"text-align: justify;\"><strong>The list of publications at the 5 years published<\/strong><\/p>\n<ol>\n<li style=\"text-align: justify;\">(with N. Guliyev) On the approximation by single hidden layer feedforward neural networks with fixed weights,\u00a0<em>Neural Networks<\/em><strong>98<\/strong>(2018), 296-304,\u00a0<a href=\"https:\/\/doi.org\/10.1016\/j.neunet.2017.12.007\">https:\/\/doi.org\/10.1016\/j.neunet.2017.12.007<\/a><\/li>\n<li style=\"text-align: justify;\">A note on the criterion for a best approximation by superpositions of functions,\u00a0<em>Studia Mathematica<\/em><strong>240\u00a0<\/strong>(2018), no. 2, 193-199,\u00a0<a href=\"https:\/\/doi.org\/10.4064\/sm170314-9-4\">https:\/\/doi.org\/10.4064\/sm170314-9-4<\/a><\/li>\n<li style=\"text-align: justify;\">(with A. Asgarova) On the representation by sums of algebras of continuous functions,\u00a0<em>Comptes Rendus Mathematique<\/em><strong>355\u00a0<\/strong>(2017), no. 9, 949-955,\u00a0<a href=\"https:\/\/doi.org\/10.1016\/j.crma.2017.09.015\">https:\/\/doi.org\/10.1016\/j.crma.2017.09.015<\/a><\/li>\n<li style=\"text-align: justify;\">A note on the equioscillation theorem for best ridge function approximation,\u00a0<em>Expositiones Mathematicae<\/em><strong>35\u00a0<\/strong>(2017), no. 3, 343-349,\u00a0<a href=\"https:\/\/doi.org\/10.1016\/j.exmath.2017.05.003\">https:\/\/doi.org\/10.1016\/j.exmath.2017.05.003<\/a><\/li>\n<li style=\"text-align: justify;\">(with A. Asgarova) Diliberto\u2013Straus algorithm for the uniform approximation by a sum of two algebras,\u00a0<em>Proceedings &#8211; Mathematical Sciences<\/em><strong>127\u00a0<\/strong>(2017), no. 2, 361-374,\u00a0<a href=\"http:\/\/dx.doi.org\/10.1007\/s12044-017-0337-4\">http:\/\/dx.doi.org\/10.1007\/s12044-017-0337-4<\/a><\/li>\n<li style=\"text-align: justify;\">(with E. Savas) Measure theoretic results for approximation by neural networks with limited weights,\u00a0<em>Numerical Functional Analysis and Optimization<\/em><strong>38<\/strong>(2017), no. 7, 819-830,\u00a0<a href=\"http:\/\/dx.doi.org\/10.1080\/01630563.2016.1254654\">http:\/\/dx.doi.org\/10.1080\/01630563.2016.1254654<\/a><\/li>\n<li>Approximation by sums of ridge functions with fixed directions, (Russian)\u00a0<em>Algebra i Analiz<\/em>\u00a0<strong>28<\/strong>\u00a0(2016), no. 6,\u00a020\u201369,\u00a0<a href=\"http:\/\/mi.mathnet.ru\/eng\/aa1513\">http:\/\/mi.mathnet.ru\/eng\/aa1513<\/a>\u00a0English transl.\u00a0<em>St. Petersburg Mathematical Journal<\/em>\u00a0<strong>28<\/strong>\u00a0(2017), 741-772,\u00a0<a href=\"https:\/\/doi.org\/10.1090\/spmj\/1471\">https:\/\/doi.org\/10.1090\/spmj\/1471<\/a>\n<ol start=\"8\">\n<li style=\"text-align: justify;\">On the uniqueness of representation by linear superpositions,\u00a0<em>Ukrainskii Matematicheskii Zhurnal<\/em><strong>68<\/strong>(2016), no. 12, 1620-1628. English transl.\u00a0<em>Ukrainian Mathematical Journal<\/em>\u00a0<strong>68\u00a0<\/strong>(2017), no. 12, 1874-1883,\u00a0<a href=\"https:\/\/doi.org\/10.1007\/s11253-017-1335-5\">https:\/\/doi.org\/10.1007\/s11253-017-1335-5<\/a><\/li>\n<li style=\"text-align: justify;\">(with N. Guliyev)\u00a0A single hidden layer feedforward network with only one neuron in the hidden layer can approximate any univariate function,\u00a0<em>Neural Computation\u00a0<\/em><strong>28<\/strong>(2016), no. 7,\u00a01289\u20131304,\u00a0<a href=\"http:\/\/dx.doi.org\/10.1162\/NECO_a_00849\">http:\/\/dx.doi.org\/10.1162\/NECO_a_00849<\/a><\/li>\n<li style=\"text-align: justify;\">(with R. Aliev) On a smoothness problem in ridge function representation,\u00a0<em>Advances in Applied Mathematics<\/em><strong>73<\/strong>(2016), 154\u2013169,\u00a0<a href=\"http:\/\/dx.doi.org\/10.1016\/j.aam.2015.11.002\">http:\/\/dx.doi.org\/10.1016\/j.aam.2015.11.002<\/a><\/li>\n<li style=\"text-align: justify;\">Approximation by ridge functions and neural networks with a bounded number of neurons,\u00a0<em>Applicable Analysis<\/em><strong>94<\/strong>(2015), no. 11, 2245-2260,\u00a0<a href=\"http:\/\/dx.doi.org\/10.1080\/00036811.2014.979809\">http:\/\/dx.doi.org\/10.1080\/00036811.2014.979809<\/a><\/li>\n<li style=\"text-align: justify;\">On the approximation by neural networks with bounded number of neurons in hidden layers,\u00a0<em>Journal of Mathematical Analysis and Applications<\/em><strong>417\u00a0<\/strong>(2014), no. 2, 963\u2013969,\u00a0<a href=\"http:\/\/dx.doi.org\/10.1016\/j.jmaa.2014.03.092\">http:\/\/dx.doi.org\/10.1016\/j.jmaa.2014.03.092<\/a><\/li>\n<li style=\"text-align: justify;\">(with A. Pinkus) Interpolation on lines by ridge functions,\u00a0<em>Journal of Approximation Theory<\/em><strong>175<\/strong>(2013), 91-113,\u00a0<a href=\"http:\/\/www.sciencedirect.com\/science\/article\/pii\/S0021904513001275\">http:\/\/dx.doi.org\/10.1016\/j.jat.2013.07.010<\/a><\/li>\n<li style=\"text-align: justify;\">Approximation by neural networks with weights varying on a finite set of directions,\u00a0<em>Journal of Mathematical Analysis and Applications<\/em><strong>389<\/strong>(2012), Issue 1, 72-83,\u00a0<a href=\"http:\/\/dx.doi.org\/10.1016\/j.jmaa.2011.11.037\">http:\/\/dx.doi.org\/10.1016\/j.jmaa.2011.11.037<\/a><\/li>\n<li style=\"text-align: justify;\">A note on the representation of continuous functions by linear superpositions,\u00a0<em>Expositiones Mathematicae<\/em><strong>30<\/strong>(2012), Issue 1, 96-101,\u00a0<a href=\"http:\/\/dx.doi.org\/10.1016\/j.exmath.2011.07.005\">http:\/\/dx.doi.org\/10.1016\/j.exmath.2011.07.005<\/a><\/li>\n<li style=\"text-align: justify;\">On the theorem of M Golomb,\u00a0<em>Proceedings &#8211; Mathematical Sciences<\/em><strong>119<\/strong>(2009), no. 1, 45-52,\u00a0<a href=\"http:\/\/dx.doi.org\/10.1007\/s12044-009-0005-4\">http:\/\/dx.doi.org\/10.1007\/s12044-009-0005-4<\/a><\/li>\n<li style=\"text-align: justify;\">On the representation by linear superpositions,\u00a0<em>Journal of Approximation Theory<\/em><strong>151<\/strong>(2008), Issue 2 , 113-125,\u00a0<a href=\"http:\/\/dx.doi.org\/10.1016\/j.jat.2007.09.003\">http:\/\/dx.doi.org\/10.1016\/j.jat.2007.09.003<\/a><\/li>\n<li style=\"text-align: justify;\">On the approximation by compositions of fixed multivariate functions with univariate functions,\u00a0<em>Studia Mathematica<\/em>\u00a0<strong>183<\/strong>\u00a0(2007), 117-126,\u00a0<a href=\"http:\/\/dx.doi.org\/10.4064\/sm183-2-2\">http:\/\/dx.doi.org\/10.4064\/sm183-2-2<\/a>\n<ol start=\"19\">\n<li>On the best L\u2082 approximation by ridge functions,\u00a0<em>Applied Mathematics E-Notes<\/em>,\u00a0<strong>7<\/strong>(2007), 71-76,\u00a0<a href=\"http:\/\/www.math.nthu.edu.tw\/~amen\/\">http:\/\/www.math.nthu.edu.tw\/~amen\/<\/a><\/li>\n<li>Representation of multivariate functions by sums of ridge functions,\u00a0<em>Journal of Mathematical Analysis and Applications<\/em><strong>331<\/strong>(2007), Issue 1, 184-190,\u00a0<a href=\"http:\/\/dx.doi.org\/10.1016\/j.jmaa.2006.08.076\">http:\/\/dx.doi.org\/10.1016\/j.jmaa.2006.08.076<\/a><\/li>\n<li>Characterization of an extremal sum of ridge functions,\u00a0<em>Journal of Computational and Applied Mathematics<\/em><strong>205<\/strong>(2007), Issue 1, 105-115,\u00a0<a href=\"http:\/\/dx.doi.org\/10.1016\/j.cam.2006.04.043\">http:\/\/dx.doi.org\/10.1016\/j.cam.2006.04.043<\/a><\/li>\n<\/ol>\n<p>22. Methods for computing the least deviation from the sums of functions of one variable, (Russian)\u00a0<em>Sibirskii Matematicheskii Zhurnal<\/em>\u00a0<strong>47<\/strong>\u00a0(2006), no. 5, 1076 -1082; translation in\u00a0<em>Siberian Mathematical Journal<\/em>\u00a0<strong>47<\/strong>\u00a0(2006), no. 5, 883\u2013888,\u00a0<a href=\"http:\/\/dx.doi.org\/10.1007\/s11202-006-0097-3\">http:\/\/dx.doi.org\/10.1007\/s11202-006-0097-3<\/a><\/li>\n<\/ol>\n<\/li>\n<\/ol>\n","protected":false},"excerpt":{"rendered":"<p>Basic scientific achievements 1) Necessary and sufficient conditions for the representation of multivariate functions by linear combinations of ridge functions were obtained; 2) A Chebyshev type theorem was proved for sums of ridge functions to be extremal to a given continuous function; 3) Explicit formulas for an exact computation of the approximation error and construction [&hellip;]<\/p>\n","protected":false},"author":6,"featured_media":0,"parent":2350,"menu_order":0,"comment_status":"open","ping_status":"open","template":"","meta":{"footnotes":""},"_links":{"self":[{"href":"https:\/\/www.imm.az\/exp\/wp-json\/wp\/v2\/pages\/3655"}],"collection":[{"href":"https:\/\/www.imm.az\/exp\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/www.imm.az\/exp\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/www.imm.az\/exp\/wp-json\/wp\/v2\/users\/6"}],"replies":[{"embeddable":true,"href":"https:\/\/www.imm.az\/exp\/wp-json\/wp\/v2\/comments?post=3655"}],"version-history":[{"count":2,"href":"https:\/\/www.imm.az\/exp\/wp-json\/wp\/v2\/pages\/3655\/revisions"}],"predecessor-version":[{"id":23346,"href":"https:\/\/www.imm.az\/exp\/wp-json\/wp\/v2\/pages\/3655\/revisions\/23346"}],"up":[{"embeddable":true,"href":"https:\/\/www.imm.az\/exp\/wp-json\/wp\/v2\/pages\/2350"}],"wp:attachment":[{"href":"https:\/\/www.imm.az\/exp\/wp-json\/wp\/v2\/media?parent=3655"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}