{"title":"Generalized $g$-iterated fractional approximations by sublinear operators","authors":"G. Anastassiou","doi":"10.4064/am2400-1-2020","DOIUrl":"https://doi.org/10.4064/am2400-1-2020","url":null,"abstract":". We study approximation of functions by sublinear positive operators with applications to several max-product operators under generalized g -iterated fractional differentiability. Our work is based on our generalized g -iterated fractional results about positive sublinear operators. We produce Jackson type inequalities under iterated initial conditions. Our approach is quantitative by deriving inequalities with right hand sides involving the modulus of continuity of a generalized g -iterated fractional derivative of the function being approximated.","PeriodicalId":52313,"journal":{"name":"Applicationes Mathematicae","volume":"7 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87900825","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Highly efficient solvers for nonlinear equations in Banach space","authors":"I. Argyros, S. George","doi":"10.4064/am2392-1-2020","DOIUrl":"https://doi.org/10.4064/am2392-1-2020","url":null,"abstract":"","PeriodicalId":52313,"journal":{"name":"Applicationes Mathematicae","volume":"10 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88184005","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"On the eigenvalues and eigenfunctions for a free boundary problem for incompressible viscous magnetohydrodynamics","authors":"P. Kacprzyk, W. Zaja̧czkowski","doi":"10.4064/AM2358-10-2018","DOIUrl":"https://doi.org/10.4064/AM2358-10-2018","url":null,"abstract":"The motion of incompressible magnetohydrodynamics (mhd) in a domain bounded by a free surface and coupled through it with an external electromagnetic field is considered. Transmission conditions for electric currents and magnetic fields are prescribed on the free surface. In this paper we show the idea of the proof of local existence by the method of successive approximations. For this we need linearized problems: the Stokes system for the velocity and pressure and the linear transmission problem for the electromagnetic field. We do not prove the local existence of solutions to the original problem but we show existence of a fundamental basis of functions for the linearized problems. Once we have such a basis, the existence of solutions to the linear problems can be shown by the Faedo–Galerkin method, as in other papers of Kacprzyk. The existence of solutions of the linear systems can also be shown by the method of regularizer.","PeriodicalId":52313,"journal":{"name":"Applicationes Mathematicae","volume":"3 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89280880","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Extensions of Kantorovich-type theorems for Newton’s method","authors":"I. Argyros, S. George, D. R. Sahu","doi":"10.4064/am2352-1-2018","DOIUrl":"https://doi.org/10.4064/am2352-1-2018","url":null,"abstract":". We extend the applicability of Newton’s method, so we can approximate a locally unique solution of a nonlinear equation in a Banach space setting in cases not covered before. To achieve this, we find a more precise set containing the Newton iterates than in earlier works.","PeriodicalId":52313,"journal":{"name":"Applicationes Mathematicae","volume":"51 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74683046","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"The optimal time decay rates for incompressible viscoelastic fluids in critical framework","authors":"Dandan Ding, Meiling Chi, Fuyi Xu","doi":"10.4064/am2409-5-2020","DOIUrl":"https://doi.org/10.4064/am2409-5-2020","url":null,"abstract":". We study the Cauchy problem for multi-dimensional incompressible viscoelastic fluids in the whole space. The optimal time decay rates of strong solution constructed by Qian (2010), and Zhang (2011) in L 2 critical regularity framework are obtained for low frequencies of the data under a suitable additional condition. The proof relies on an application of Fourier analysis to a mixed parabolic-hyperbolic system, and on a refined time-weighted energy functional. As a by-product, time decay rates of L q - L r type are also captured in the critical framework.","PeriodicalId":52313,"journal":{"name":"Applicationes Mathematicae","volume":"13 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79521635","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Ball convergence for a sixth-order multi-point method in Banach spaces under weak conditions","authors":"I. Argyros, S. George","doi":"10.4064/AM2350-2-2018","DOIUrl":"https://doi.org/10.4064/AM2350-2-2018","url":null,"abstract":"","PeriodicalId":52313,"journal":{"name":"Applicationes Mathematicae","volume":"49 1","pages":"133-144"},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73105198","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
B. Escobedo-Trujillo, O. Hernández-Lerma, F. A. Alaffita-Hernández
{"title":"Adaptive control of diffusion processes with a discounted reward criterion","authors":"B. Escobedo-Trujillo, O. Hernández-Lerma, F. A. Alaffita-Hernández","doi":"10.4064/am2421-10-2020","DOIUrl":"https://doi.org/10.4064/am2421-10-2020","url":null,"abstract":". The optimal control problem we are dealing with in this paper is to determine control policies that maximize a discounted reward criterion when the dynamic system evolves as a stochastic differential equation (SDE). Both the instantaneous reward function and the SDE’s drift coef-ficient may depend on an unknown parameter. We give conditions ensur-ing the existence of an asymptotically optimal policy using the so-called Principle of Estimation and Control. We illustrate our results with several examples.","PeriodicalId":52313,"journal":{"name":"Applicationes Mathematicae","volume":"29 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78206633","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Local convergence for multistep high order methods under weak conditions","authors":"I. Argyros, R. Behl, D. González, S. Motsa","doi":"10.4064/am2374-1-2019","DOIUrl":"https://doi.org/10.4064/am2374-1-2019","url":null,"abstract":"","PeriodicalId":52313,"journal":{"name":"Applicationes Mathematicae","volume":"15 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91235981","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"New Weierstrass elliptic wave solutions of the Davey–Stewartson equation with power law nonlinearity","authors":"A. Achab","doi":"10.4064/am2386-4-2020","DOIUrl":"https://doi.org/10.4064/am2386-4-2020","url":null,"abstract":"","PeriodicalId":52313,"journal":{"name":"Applicationes Mathematicae","volume":"47 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88617560","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Stochastic approximation procedure in semi-Markov environment applied to alcohol consumption model","authors":"W. Rosa","doi":"10.4064/am2382-9-2019","DOIUrl":"https://doi.org/10.4064/am2382-9-2019","url":null,"abstract":". In this paper, we consider a stochastic approximation procedure with semi-Markov switchings in an averaging scheme with a small parameter.","PeriodicalId":52313,"journal":{"name":"Applicationes Mathematicae","volume":"60 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86879548","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}