Calculus of Variations and Nonlinear Partial Differential Equations

A special issue of Axioms (ISSN 2075-1680). This special issue belongs to the section "Mathematical Analysis".

Deadline for manuscript submissions: closed (30 November 2022) | Viewed by 21033
Please contact the Guest Editor or the Journal Editor ([email protected]) for any queries about the scope, discount, submission procedure and publication process.

Special Issue Editor

Special Issue Information

Dear Colleagues,

The current Special Issue invites studies related to the calculus of variations and nonlinear partial differential equations. More specifically, this Special Issue aims to develop essential tools for solving problems arising in various branches of mathematical analysis, such as variational inequality problems, nonlinear optimization problems, equilibrium problems, complementarity problems, and integral and differential equations.

The main objective of this Special Issue is to provide a platform for researchers to report new initiatives and developments in the field of nonlinear analysis, calculus of variations, and partial differential equations. Original research and review articles are welcome.

Prof. Dr. Savin Treanţă
Guest Editor

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Axioms is an international peer-reviewed open access monthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2400 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

  • optimization problems and applications
  • variational problems and their applications
  • topological approaches in nonlinear problems
  • partial differential equations
  • optimal control
  • variational and topological methods for PDEs
  • convex analysis
  • generalized differentiability

Benefits of Publishing in a Special Issue

  • Ease of navigation: Grouping papers by topic helps scholars navigate broad scope journals more efficiently.
  • Greater discoverability: Special Issues support the reach and impact of scientific research. Articles in Special Issues are more discoverable and cited more frequently.
  • Expansion of research network: Special Issues facilitate connections among authors, fostering scientific collaborations.
  • External promotion: Articles in Special Issues are often promoted through the journal's social media, increasing their visibility.
  • e-Book format: Special Issues with more than 10 articles can be published as dedicated e-books, ensuring wide and rapid dissemination.

Further information on MDPI's Special Issue polices can be found here.

Published Papers (8 papers)

Order results
Result details
Select all
Export citation of selected articles as:

Research

20 pages, 3672 KiB  
Article
Vibration of a Flexible Follower in a Cam Mechanism with Time-Dependent Boundary Effect
by Jer-Rong Chang
Axioms 2023, 12(2), 177; https://doi.org/10.3390/axioms12020177 - 8 Feb 2023
Viewed by 2029
Abstract
A vibration analysis of a flexible follower in an oscillating follower cam system undergoing a rise-dwell-fall-dwell (RDFD) motion is performed. Owing to the time-dependent boundary effect caused by considering simultaneously the axial and the lateral displacements of the follower, two geometric constraints are [...] Read more.
A vibration analysis of a flexible follower in an oscillating follower cam system undergoing a rise-dwell-fall-dwell (RDFD) motion is performed. Owing to the time-dependent boundary effect caused by considering simultaneously the axial and the lateral displacements of the follower, two geometric constraints are formulated and added to Hamilton’s principle to establish the vibration equation of the motion of the follower. The coupled axial and lateral vibration of the flexible follower has been studied for the first time. The fast Fourier transform (FFT) spectrum generated from the time history is used for parametric studies. The numerical results of the present study show some new findings. The major spectral peaks for the lateral follower response locate at the low frequencies of 1 Ω, 3 Ω, 5 Ω, and 7 Ω and the high frequency near the fundamental natural frequency where Ω is the cam speed. The largest peak locates mostly at the frequency of 3 Ω. For the ascending and descending motions of the follower RDFD motion, three types of cam profiles are designed. Important new results are found: although the three cam profiles nearly overlap, the vibration results of the follower are quite different. By using a modified sinusoidal acceleration motion, the magnitude of the main lateral peak at low frequencies is minimized. The lateral peak amplitude near the fundamental natural frequency of the follower is the smallest when the cycloid displacement motion is adopted. Full article
(This article belongs to the Special Issue Calculus of Variations and Nonlinear Partial Differential Equations)
Show Figures

Figure 1

13 pages, 1655 KiB  
Article
A Very Simple Procedure for Constructing the Solution of Nonlinear Elliptic PDEs (with Nonlinear Boundary Conditions) Arising from Heat Transfer Problems in Solids
by Rogério Martins Saldanha da Gama
Axioms 2022, 11(7), 311; https://doi.org/10.3390/axioms11070311 - 26 Jun 2022
Cited by 1 | Viewed by 1625
Abstract
This work presents a procedure for constructing the solution of a second order nonlinear partial differential equation subjected to nonlinear boundary conditions in a very simple and systematic way. The class of equations to be considered here includes, but is not limited to, [...] Read more.
This work presents a procedure for constructing the solution of a second order nonlinear partial differential equation subjected to nonlinear boundary conditions in a very simple and systematic way. The class of equations to be considered here includes, but is not limited to, the partial differential equations which govern the steady-state heat transfer process in bodies with temperature-dependent thermal conductivity and temperature-dependent internal heat source. In addition, it will be considered a large class of nonlinear boundary conditions, especially those arising from the description of the heat exchange process from/to bodies at high temperature levels. Proofs of the solution’s existence and uniqueness are presented. Full article
(This article belongs to the Special Issue Calculus of Variations and Nonlinear Partial Differential Equations)
Show Figures

Figure 1

21 pages, 2066 KiB  
Article
Dynamical Analysis of a Modified Epidemic Model with Saturated Incidence Rate and Incomplete Treatment
by Lazarus Kalvein Beay and Nursanti Anggriani
Axioms 2022, 11(6), 256; https://doi.org/10.3390/axioms11060256 - 27 May 2022
Cited by 3 | Viewed by 2865
Abstract
This paper addresses a modified epidemic model with saturated incidence and incomplete treatment. The existence of all equilibrium points is analyzed. A reproduction number R0 is determined. Next, it is found that the non-endemic point P0 is stable in case [...] Read more.
This paper addresses a modified epidemic model with saturated incidence and incomplete treatment. The existence of all equilibrium points is analyzed. A reproduction number R0 is determined. Next, it is found that the non-endemic point P0 is stable in case R0<1, but unstable in case R0>1. The special conditions to analyze the local and global stability of the non-endemic and endemic points are investigated. Globally, the sensitivity analysis of the system is studied by combining the Latin Hypercube Sampling and Partial Rating Correlation Coefficients methods. By using the Pontryagins maximum principle, the optimal control problem is studied. Various numerical results are given to support our analysis. Full article
(This article belongs to the Special Issue Calculus of Variations and Nonlinear Partial Differential Equations)
Show Figures

Figure 1

16 pages, 2635 KiB  
Article
Exact Solutions of Nonlinear Partial Differential Equations via the New Double Integral Transform Combined with Iterative Method
by Shams A. Ahmed, Ahmad Qazza and Rania Saadeh
Axioms 2022, 11(6), 247; https://doi.org/10.3390/axioms11060247 - 25 May 2022
Cited by 40 | Viewed by 4244
Abstract
This article demonstrates how the new Double Laplace–Sumudu transform (DLST) is successfully implemented in combination with the iterative method to obtain the exact solutions of nonlinear partial differential equations (NLPDEs) by considering specified conditions. The solutions of nonlinear terms of these equations were [...] Read more.
This article demonstrates how the new Double Laplace–Sumudu transform (DLST) is successfully implemented in combination with the iterative method to obtain the exact solutions of nonlinear partial differential equations (NLPDEs) by considering specified conditions. The solutions of nonlinear terms of these equations were determined by using the successive iterative procedure. The proposed technique has the advantage of generating exact solutions, and it is easy to apply analytically on the given problems. In addition, the theorems handling the mode properties of the DLST have been proved. To prove the usability and effectiveness of this method, examples have been given. The results show that the presented method holds promise for solving other types of NLPDEs. Full article
(This article belongs to the Special Issue Calculus of Variations and Nonlinear Partial Differential Equations)
Show Figures

Figure 1

13 pages, 3634 KiB  
Article
Investigation into the Explicit Solutions of the Integrable (2+1)—Dimensional Maccari System via the Variational Approach
by Kang-Jia Wang and Jing Si
Axioms 2022, 11(5), 234; https://doi.org/10.3390/axioms11050234 - 18 May 2022
Cited by 28 | Viewed by 2284
Abstract
In this paper, the integrable (2+1)-dimensional Maccari system (MS), which can model many complex phenomena in hydrodynamics, plasma physics and nonlinear optics, is investigated by the variational approach (VA). This proposed approach that based on the variational theory and Ritz-like method can construct [...] Read more.
In this paper, the integrable (2+1)-dimensional Maccari system (MS), which can model many complex phenomena in hydrodynamics, plasma physics and nonlinear optics, is investigated by the variational approach (VA). This proposed approach that based on the variational theory and Ritz-like method can construct the explicit solutions via the stationary conditions only taking two steps. Finally, the dynamic behaviors of the solutions are exhibited by choosing the appropriate parameters through the 3-D and density plots. It can be seen that the proposed method is concise and straightforward, and can be adopted to study the travelling wave theory in physics. Full article
(This article belongs to the Special Issue Calculus of Variations and Nonlinear Partial Differential Equations)
Show Figures

Figure 1

8 pages, 235 KiB  
Article
A New Equilibrium Version of Ekeland’s Variational Principle and Its Applications
by Yuqiang Feng, Juntao Xie and Bo Wu
Axioms 2022, 11(2), 68; https://doi.org/10.3390/axioms11020068 - 9 Feb 2022
Viewed by 2007
Abstract
In this note, a new equilibrium version of Ekeland’s variational principle is presented. It is a modification and promotion of previous results. Subsequently, the principle is applied to discuss the equilibrium points for binary functions and the fixed points for nonlinear mappings. Full article
(This article belongs to the Special Issue Calculus of Variations and Nonlinear Partial Differential Equations)
16 pages, 277 KiB  
Article
A Straightforward Sufficiency Proof for a Nonparametric Problem of Bolza in the Calculus of Variations
by Gerardo Sánchez Licea
Axioms 2022, 11(2), 55; https://doi.org/10.3390/axioms11020055 - 29 Jan 2022
Cited by 1 | Viewed by 2006
Abstract
We study a variable end-points calculus of variations problem of Bolza containing inequality and equality constraints. The proof of the principal theorem of the paper has a direct nature since it is independent of some classical sufficiency approaches invoking the Hamiltonian-Jacobi theory, Riccati [...] Read more.
We study a variable end-points calculus of variations problem of Bolza containing inequality and equality constraints. The proof of the principal theorem of the paper has a direct nature since it is independent of some classical sufficiency approaches invoking the Hamiltonian-Jacobi theory, Riccati equations, fields of extremals or the theory of conjugate points. In contrast, the algorithm employed to prove the principal theorem of the article is based on elementary tools of the real analysis. Full article
(This article belongs to the Special Issue Calculus of Variations and Nonlinear Partial Differential Equations)
17 pages, 311 KiB  
Article
On Constrained Set-Valued Semi-Infinite Programming Problems with ρ-Cone Arcwise Connectedness
by Koushik Das and Savin Treanţă
Axioms 2021, 10(4), 302; https://doi.org/10.3390/axioms10040302 - 12 Nov 2021
Cited by 4 | Viewed by 1430
Abstract
In this paper, we establish sufficient Karush–Kuhn–Tucker (for short, KKT) conditions of a set-valued semi-infinite programming problem (SP) via the notion of contingent epiderivative of set-valued maps. We also derive duality results of Mond–Weir (MWD), Wolfe (WD), and mixed (MD) types of the [...] Read more.
In this paper, we establish sufficient Karush–Kuhn–Tucker (for short, KKT) conditions of a set-valued semi-infinite programming problem (SP) via the notion of contingent epiderivative of set-valued maps. We also derive duality results of Mond–Weir (MWD), Wolfe (WD), and mixed (MD) types of the problem (SP) under ρ-cone arcwise connectedness assumptions. Full article
(This article belongs to the Special Issue Calculus of Variations and Nonlinear Partial Differential Equations)
Back to TopTop