Journal of Nonlinear Analysis and Optimization: Theory & Applications (JNAO) https://ph03.tci-thaijo.org/index.php/jnao <p><strong>Journal of Nonlinear Analysis and Optimization: Theory &amp; Applications</strong> is a peer-reviewed, open-access international journal, that devotes to the publication of original articles of current interest in every theoretical, computational, and applicational aspect of nonlinear analysis, convex analysis, fixed point theory, and optimization techniques and their applications to science and engineering. All manuscripts are refereed under the same standards as those used by the finest-quality printed mathematical journals. Accepted papers will be published in two issues annually in June and December, free of charge. This journal was conceived as the main scientific publication of the Center of Excellence in Nonlinear Analysis and Optimization, Naresuan University, Thailand.</p> Center of Excellence in Nonlinear Analysis and Optimization, Naresuan University, Phitsanulok 65000 Thailand en-US Journal of Nonlinear Analysis and Optimization: Theory & Applications (JNAO) 1906-9685 <p>Copyright (c) 2010 Journal of Nonlinear Analysis and Optimization: Theory &amp; Applications</p> <p><img src="https://i.creativecommons.org/l/by-nc-nd/4.0/88x31.png" alt="Creative Commons License" /></p> <p>This work is licensed under aย <a href="https://creativecommons.org/licenses/by-nc-nd/4.0/" rel="license">Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License</a>.</p> Episodes in Metric Fixed Point Theory related to F. E. Browder https://ph03.tci-thaijo.org/index.php/jnao/article/view/1568 <p>F.E. Browder in 1979 posed a fixed point theorem of great generality<br />and complexity such that a large part of literature on contractive type of <br />mapscan be subsumed under an intuitive and simple mode of argument.<br />Immediately after, several researchers found better theorems than his <br />result. Since then only a few authors quote his theorem. However, until <br />recently, certain minor papers related to Browder's aim.Our aim in this <br />paper is to introduce the contents of them.</p> Sehie Park Copyright (c) 2024 Journal of Nonlinear Analysis and Optimization: Theory & Applications (JNAO) https://creativecommons.org/licenses/by-nc-nd/4.0 2024-06-01 2024-06-01 15 1 1 11 Best Proximity Point and Fixed Point Theorems in Complex Valued Rectangular b-Metric Spaces https://ph03.tci-thaijo.org/index.php/jnao/article/view/629 <p>The aim of this paper, by using the concept of continuity of <img title="\phi :[0, \infty)^{2}\rightarrow [0, \infty)^{2}" src="https://latex.codecogs.com/gif.latex?\phi&amp;space;:[0,&amp;space;\infty)^{2}\rightarrow&amp;space;[0,&amp;space;\infty)^{2}">&nbsp;which satisfying <img title="\phi (t)\prec t" src="https://latex.codecogs.com/gif.latex?\phi&amp;space;(t)\prec&amp;space;t"><br>and <img title="\phi (0)=0" src="https://latex.codecogs.com/gif.latex?\phi&amp;space;(0)=0"> to defined some contraction condition of T introduced by G. Meena [12], we prove the unique<br>best proximity point of A and fixed point of T in complex valued rectangular b-metric space. Our results<br>extend and improve the results of G. Meena [12], and many others.</p> Warinsinee Chantakun Tadchai Yuying Suchinda Sattayaporn Copyright (c) 2024 Journal of Nonlinear Analysis and Optimization: Theory & Applications (JNAO) https://creativecommons.org/licenses/by-nc-nd/4.0 2024-06-01 2024-06-01 15 1 13 22 FIXED POINT THEOREMS FOR ĆIRIĆ’S QUASICONTRACTION IN GENERALIZED COMPLEX VALUED METRIC SPACES https://ph03.tci-thaijo.org/index.php/jnao/article/view/1970 <p>In this work, we introduce some property of the generalized complex valued<br>metric space and we extend some fixed point results thai is Ćirić’s fixed point theorem.<br>Some are recover various complex valued metric space and complex valued b-metric space.<br>Our results extended and improve some results of Mohamed Jleli and Bessem Samet [14].</p> Tadchai Yuying Issara Inchan Kiattisak Rattanaseeha Copyright (c) 2024 Journal of Nonlinear Analysis and Optimization: Theory & Applications (JNAO) https://creativecommons.org/licenses/by-nc-nd/4.0 2024-06-01 2024-06-01 15 1 23 31 SOLVABILITY OF EQUATIONS INVOLVING PERTURBATIONS OF m-ACCRETIVE OPERATORS IN BANACH SPACES https://ph03.tci-thaijo.org/index.php/jnao/article/view/1567 <p>It is purpose of this paper to give several results for the solvability of the<br>equation p ∈ Ax + Sx, where A is an m-accretive operator on a Banach space E and S<br>is a mapping on a subset of E, with elementary proofs. We give proofs of them without<br>using degree theory.</p> Masashi Toyoda Yukio Takeuchi Copyright (c) 2024 Journal of Nonlinear Analysis and Optimization: Theory & Applications (JNAO) https://creativecommons.org/licenses/by-nc-nd/4.0 2024-06-01 2024-06-01 15 1 33 42