{"title":"Kantorovich’s Theorem on Mann’s Iteration Method in Riemannian Manifold","authors":"Babita Mehta, P. K. Parida, Sapan Kumar Nayak","doi":"10.1007/s40306-024-00541-9","DOIUrl":"10.1007/s40306-024-00541-9","url":null,"abstract":"<div><p>Convergence analysis of Mann’s iteration method using Kantorovich’s theorem in the context of connected and complete Riemannian manifolds has been examined in this paper. We also provide an algorithm for Mann’s method to find a singularity in a two dimensional sphere <span>(S^2)</span>. Finally, we provide an example that shows the better convergence result of Mann’s method in comparison to that of Newton’s method.</p></div>","PeriodicalId":45527,"journal":{"name":"Acta Mathematica Vietnamica","volume":"49 4","pages":"629 - 648"},"PeriodicalIF":0.3,"publicationDate":"2024-06-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142762043","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":"A Primal-dual Backward Reflected Forward Splitting Algorithm for Structured Monotone Inclusions","authors":"Vũ Công Bằng, Dimitri Papadimitriou, Vũ Xuân Nhâm","doi":"10.1007/s40306-024-00535-7","DOIUrl":"10.1007/s40306-024-00535-7","url":null,"abstract":"<div><p>We propose a primal-dual backward reflected forward splitting method for solving structured primal-dual monotone inclusions in real Hilbert spaces. The algorithm allows to use the inexact computations of Lipschitzian and cocoercive operators. The strong convergence of the generated iterative sequence is proved under the strong monotonicity condition, whilst the weak convergence is formally proved under several conditions used in the literature. An application to a structured minimization problem is provided.</p></div>","PeriodicalId":45527,"journal":{"name":"Acta Mathematica Vietnamica","volume":"49 2","pages":"159 - 172"},"PeriodicalIF":0.3,"publicationDate":"2024-06-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142414659","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 Convergence for Randomly Weighted Sums of Hilbert-valued Coordinatewise Pairwise NQD Random Variables","authors":"Cuong Manh Tran, Chien Van Ta, Hang Bui Khanh","doi":"10.1007/s40306-024-00537-5","DOIUrl":"10.1007/s40306-024-00537-5","url":null,"abstract":"<div><p>In this paper, we present the complete convergence for weighted sums of coordinatewise pairwise negative quadrant dependent random variables taking values in Hilbert spaces. As an application of the results, the complete convergence of degenerate von Mises statistics is investigated.</p></div>","PeriodicalId":45527,"journal":{"name":"Acta Mathematica Vietnamica","volume":"49 2","pages":"265 - 281"},"PeriodicalIF":0.3,"publicationDate":"2024-06-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141337202","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":"Linear Singular Continuous Time-varying Delay Equations: Stability and Filtering via LMI Approach","authors":"Vu Ngoc Phat, Nguyen Truong Thanh","doi":"10.1007/s40306-024-00534-8","DOIUrl":"10.1007/s40306-024-00534-8","url":null,"abstract":"<div><p>In this paper, we propose an LMI-based approach to study stability and <span>(H_infty )</span> filtering for linear singular continuous equations with time-varying delay. Particularly, the delay pattern is quite general and includes non-differentiable time-varying delay. First, new delay-dependent sufficient conditions for the admissibility of the equation are extended to the time-varying delay case. Then, we propose a design of <span>(H_infty )</span> filters via feasibility problem involving linear matrix inequalities, which can be solved by the standard numerical algorithm. The proposed result is demonstrated through an example and simulations.</p></div>","PeriodicalId":45527,"journal":{"name":"Acta Mathematica Vietnamica","volume":"49 4","pages":"595 - 609"},"PeriodicalIF":0.3,"publicationDate":"2024-06-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141342653","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 Weighted (L^{p})-Sobolev Estimates for Solutions of the (overline{partial })-equation on Linearly Convex Domains of Finite Type and Application","authors":"P. Charpentier, Y. Dupain","doi":"10.1007/s40306-024-00530-y","DOIUrl":"10.1007/s40306-024-00530-y","url":null,"abstract":"<div><p>We obtain some weighted <span>(L^{p})</span>-Sobolev estimates with gain on <i>p</i> and the weight for solutions of the <span>(overline{partial })</span>-equation in linearly convex domains of finite type in <span>(mathbb {C}^{n})</span> and apply them to obtain weighted <span>(L^{p})</span>-Sobolev estimates for weighted Bergman projections of convex domains of finite type for quite general weights equivalent to a power of the distance to the boundary.</p></div>","PeriodicalId":45527,"journal":{"name":"Acta Mathematica Vietnamica","volume":"49 2","pages":"217 - 240"},"PeriodicalIF":0.3,"publicationDate":"2024-06-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142411272","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":"Source Identification for Parabolic Equations from Integral Observations by the Finite Difference Splitting Method","authors":"Nguyen Thi Ngoc Oanh","doi":"10.1007/s40306-024-00536-6","DOIUrl":"10.1007/s40306-024-00536-6","url":null,"abstract":"<div><p>We study the problem of reconstructing an unknown source term in parabolic equations from integral observations. It is reformulated into a variational problem in combination with Tikhonov regularization and then a formula for the gradient of the objective functional to be minimized is computed via a solution of an adjoint problem. The variational problem is discretized by the splitting method based on finite difference schemes and solved by the conjugate gradient method. A numerical scheme for numerically estimating singular values of the solution operator in the inverse problem is suggested. Some numerical examples are presented to show the efficiency of the method.</p></div>","PeriodicalId":45527,"journal":{"name":"Acta Mathematica Vietnamica","volume":"49 2","pages":"283 - 308"},"PeriodicalIF":0.3,"publicationDate":"2024-06-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141360103","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}
Peter Marius Flydal, Gereon Quick, Eirik Eik Svanes
{"title":"A Note on Real Line Bundles with Connection and Real Smooth Deligne Cohomology","authors":"Peter Marius Flydal, Gereon Quick, Eirik Eik Svanes","doi":"10.1007/s40306-024-00538-4","DOIUrl":"10.1007/s40306-024-00538-4","url":null,"abstract":"<div><p>We define a Real version of smooth Deligne cohomology for manifolds with involution which interpolates between equivariant sheaf cohomology and smooth imaginary-valued forms. Our main result is a classification of Real line bundles with Real connection on manifolds with involution.</p></div>","PeriodicalId":45527,"journal":{"name":"Acta Mathematica Vietnamica","volume":"49 2","pages":"187 - 199"},"PeriodicalIF":0.3,"publicationDate":"2024-06-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s40306-024-00538-4.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142410022","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Meromorphic Solutions of a Certain Type of Nonlinear Differential Equations","authors":"Yan-Yan Feng, Jun-Fan Chen","doi":"10.1007/s40306-024-00539-3","DOIUrl":"10.1007/s40306-024-00539-3","url":null,"abstract":"<div><p>In this paper, using Nevanlinna theory and linear algebra, we characterize transcendental meromorphic solutions of nonlinear differential equation of the form </p><div><div><span>$$begin{aligned} f^n+Q_d(z,f)=sum _{i=1}^{l}p_{i}(z)e^{alpha _{i}(z)}, end{aligned}$$</span></div></div><p>where <span>(lge 2)</span>, <span>(nge l+2)</span> are integers, <i>f</i>(<i>z</i>) is a meromorphic function, <span>(Q_d(z,f))</span> is a differential polynomial in <i>f</i>(<i>z</i>) of degree <span>(dle n-(l+1))</span> with rational functions as its coefficients, <span>(p_{1}(z))</span>, <span>(p_{2}(z))</span>, <span>(dots )</span>, <span>(p_{l}(z))</span> are non-vanishing rational functions and <span>(alpha _{1}(z))</span>, <span>(alpha _{2}(z))</span>, <span>(dots )</span>, <span>(alpha _{l}(z))</span> are nonconstant polynomials such that <span>(alpha _{1}^prime (z))</span>, <span>(alpha _{2}^prime (z))</span>, <span>(dots )</span>, <span>(alpha _{l}^prime (z))</span> are distinct. Further, we give the necessary conditions for the existence of meromorphic solutions of the above equation, and supply the example to demonstrate the sharpness of the condition of the obtained theorem.</p></div>","PeriodicalId":45527,"journal":{"name":"Acta Mathematica Vietnamica","volume":"49 2","pages":"173 - 186"},"PeriodicalIF":0.3,"publicationDate":"2024-05-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142415235","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":"Tight Closure, Coherence, and Localization at Single Elements","authors":"Neil Epstein","doi":"10.1007/s40306-024-00533-9","DOIUrl":"10.1007/s40306-024-00533-9","url":null,"abstract":"<div><p>In this note, a condition (<i>open persistence</i>) is presented under which a (pre)closure operation on submodules (resp. ideals) over rings of global sections over a scheme <i>X</i> can be extended to a (pre)closure operation on sheaves of submodules of a coherent <span>(mathcal {O}_X)</span>-module (resp. sheaves of ideals in <span>(mathcal {O}_X)</span>). A second condition (<i>glueability</i>) is given for such an operation to behave nicely. It is shown that for an operation that satisfies both conditions, the question of whether the operation commutes with localization at single elements is equivalent to the question of whether the new operation preserves quasi-coherence. It is shown that both conditions hold for tight closure and some of its important variants, thus yielding a geometric reframing of the open question of whether tight closure localizes at single elements. A new singularity type (<i>semi F-regularity</i>) arises, which sits between F-regularity and weak F-regularity. The paper ends with (1) a case where semi F-regularity and weak F-regularity coincide, and (2) a case where they cannot coincide without implying a solution to a major conjecture.</p></div>","PeriodicalId":45527,"journal":{"name":"Acta Mathematica Vietnamica","volume":"49 2","pages":"201 - 215"},"PeriodicalIF":0.3,"publicationDate":"2024-05-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s40306-024-00533-9.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142413482","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"On Topological Representation Theory from Quivers","authors":"Fang Li, Zhihao Wang, Jie Wu, Bin Yu","doi":"10.1007/s40306-024-00531-x","DOIUrl":"10.1007/s40306-024-00531-x","url":null,"abstract":"<div><p>In this work, we introduce <i>topological representations of a quiver</i> as a system consisting of topological spaces and its relationships determined by the quiver. Such a setting gives a natural connection between topological representations of a quiver and diagrams of topological spaces. Firstly, we investigate the relation between the category of topological representations and that of linear representations of a quiver via <span>(P(varGamma ))</span>-<span>(mathcal {TOP}^o)</span> and <span>(kvarGamma )</span>-Mod, concerning (positively) graded or vertex (positively) graded modules. Secondly, we discuss the homological theory of topological representations of quivers via the <span>(varGamma )</span>-limit functor <span>(lim ^{varGamma })</span>, and use it to define the homology groups of topological representations of quivers via <span>(H _n)</span>. It is found that some properties of a quiver can be read from homology groups. Thirdly, we investigate the homotopy theory of topological representations of quivers. We define the homotopy equivalence between two morphisms in <span>({textbf {Top}}text{- }{} {textbf {Rep}}varGamma )</span> and show that the parallel Homotopy Axiom also holds for top-representations based on the homotopy equivalence. Last, we obtain the functor <span>(At^{varGamma })</span> from <span>({textbf {Top}}text{- }{} {textbf {Rep}}varGamma )</span> to <span>({textbf {Top}})</span> and show that <span>(At^{varGamma })</span> preserves homotopy equivalence between morphisms. The relationship between the homotopy groups of a top-representation (<i>T</i>, <i>f</i>) and the homotopy groups of <span>(At^{varGamma }(T,f))</span> is also established.</p></div>","PeriodicalId":45527,"journal":{"name":"Acta Mathematica Vietnamica","volume":"49 4","pages":"563 - 594"},"PeriodicalIF":0.3,"publicationDate":"2024-05-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142761893","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}