Abstract
This work is concerned with the new notion called generalized --accretive mapping that is the sum of two symmetric accretive mappings. It is an extension of the generalized --accretive mapping. The proximal point mapping linked to the generalized --accretive mappings is defined, and some of its characteristics are discussed. As an application of the new proximal point mapping, we consider a set-valued variational inclusion problem in q-uniformly smooth Banach spaces. Further, we propose an iterative scheme connected with --proximal point mapping to find the solution of a variational inclusion problem and discuss its convergence criteria under appropriate assumptions. Some examples are constructed in support of generalized --accretive mappings.
Keywords:
generalized αiβj-Hp(., ., ...)-accretive mappings; iterative algorithm; proximal point mapping; variational inclusion MSC:
47H19; 49J40
1. Introduction and Preliminaries
Variational inequality is a very powerful tool to study a large variety of problems that appear in electricity, mechanics, operation research, optimal control, etc. The projection mapping techniques, shrinking projection mapping techniques, CQ methods, and proximal-point mapping techniques have been widely used to solve variational inequality (inclusions) problems, see [1,2,3,4,5,6,7,8,9]. The accretive property of the underlying proximal-point mapping has a significant role in the field of variational inequalities and their generalizations. Huang and Fang [10] were the first to consider and study m-accretive mappings and related proximal-point mappings in Banach spaces. After that, many researchers introduced and studied different kinds of generalized m-accretive mappings, see [1,4,5,6]. Sun et al. [7] proposed and analyzed M-monotone mappings in Hilbert spaces. A few research works linked to the M-monotone are provided in [3,9].
In particular, the investigation of -accretive mappings has been very deeply carried out, and there have been many important results on the variational inclusions (or inequalities) for their related mappings, e.g., the characterization of -monotone operators with applications to variational inclusions [11], the generalized nonlinear set-valued mixed quasi-variational inequalities [12], and the completely generalized set-valued quasi-variational inclusions [13].
In recent years, -accretive mappings and generalized --accretive mappings have been investigated and studied by many researchers, see for example, [3,9,14]. Very recently, Nazemi [15] investigated and studied -monotone mappings, and Guan and Hu [16] considered --monotone mappings in Banach spaces and studied some classes of variational inclusions involving these mappings.
Impelled by the ongoing research work presented above, in this paper we consider the generalized --accretive mapping defined on a product set, which is the sum of two symmetric accretive mappings. This notion is a generalized form of generalized --accretive mapping et al. [3], which is done with the idea of monotone mapping studied and analyzed by Nazemi [15]. We define the proximal-point mapping associated with the generalized --accretive mappings and prove that it is single-valued and Lipschitz continuous. An iterative algorithm involving a generalized --accretive mapping is constructed. We perform the convergence part of an iterative algorithm for the solution of set-valued variational inclusion problems with some suitable assumptions in the setting of q-uniformly smooth Banach spaces. Some examples are constructed in support of generalized --accretive mappings. Using the generalized --accretive mapping technique described in this paper, one can extend and improve the results given in [3,9,14,15,16,17,18,19,20,21,22,23,24].
Let Y be a real Banach space endowed with the norm and an inner product , which presents the generalized duality pairing between Y and . Let be the family of all nonempty closed and bounded subsets of Y and be the power set of of Y. We set Yp = .
Definition 1
([25]). The generalized duality mapping is defined by
where is a constant. In particular, is the usual normalized duality mapping. It is known that, in general, If Y is equivalent to real Hilbert space X, then becomes an identity mapping on X.
Definition 2
([25]). A Banach space Y is smooth if, for every with there exists a unique such that .
Definition 3
([25]). Let be a mapping; then, the modulus of smoothness of Y at μ is defined by
Definition 4
([25]). A Banach space Y is said to be
- (i)
- uniformly smooth if
- (ii)
- q-uniformly smooth, ∃with
It is observed that is single-valued if Y is uniformly smooth.
Lemma 1
([25]). A real uniformly smooth Banach space Y is q-uniformly smooth if and only if there exists a constant such that, for every
The following new notions are needed to continue subsequent sections.
Definition 5.
For , let be a mapping and be a single-valued mapping. Then, is said to be
- (i)
- -strongly accretive with if there exists such that
- (ii)
- -relaxed accretive with if there exists such that
- (iii)
- -Lipschitz continuous with if there exists such that
- (iv)
- -symmetric accretive with if and only if, for , is -strongly accretive with , and for , is -relaxed accretive with , where p is even, satisfyingand if and only if ;
- (v)
- -symmetric accretive with if and only if, for ,is -strongly accretive with , and for , is -relaxed accretive where p is odd, satisfyingand iff .
Definition 6.
For , let be a set-valued mapping and be a single-valued mapping. Then, is said to be
- (i)
- -strongly accretive with if there exists such that
- (ii)
- -relaxed accretive with if there exists such that
- (iii)
- -symmetric accretive with if and only if, for , is -strongly accretive with , and for , is -relaxed accretive with , where p is even, satisfyingand iff ;
- (iv)
- -symmetric accretive with if and only if, for , is -strongly accretive with , and for , is -relaxed accretive with , where p is odd, satisfyingand if and only if .
Definition 7.
For let , be set-valued mappings, be mappings, and be single-valued mappings; then, F is said to be
- (i)
- -strongly accretive with and in the -argument if there exists such that
- (ii)
- -Lipschitz continuous in the -argument if there exists such that
2. Generalized αiβj-Hp Accretive Mappings
At first, we consider some assumptions (-) to introduce and study the new notion generalized --accretive mappings.
For let be a set-valued mapping, be a mapping, and be single-valued mappings.
- : If p is an even number, is -symmetric accretive with .
- : If p is an odd number, is -symmetric accretive with .
- : If p is an even number, N is -symmetric accretive with .
- : If p is an odd number, N is -symmetric accretive with .
Definition 8.
Let ; then, is said to be a generalized --accretive mapping with and
- (i)
- if and only if is -symmetric accretive with (i.e., assumption holds), and , for all , if p is an even number;
- (ii)
- if and only if is -symmetric accretive with (i.e., assumption holds), and , for all , if p is an odd number.
Example 1.
Let p be an even number and be -symmetric accretive with . Let be a functional on Y; then, the vector , such that
where is finite for each , is known as the subgradient of f at z. The collections of all such subgradients of f at z holding (1) are known as the subdifferential of f at z. Let be locally Lipschitz functionals on Y such that subdifferential is -symmetric accretive with . Then, is -strongly accretive, where ; equivalently, we can state that is a generalized --accretive mapping.
Example 2.
For each , p is an even number, and (see Appendix A). Let and be the mappings, which are defined as:
such that the inequality is satisfied for all
Let be a set-valued mapping defined as:
Then, is -strongly accretive with and -relaxed accretive with , and is -strongly accretive with and -relaxed accretive with .
One can easily verify the following for :
Hence, is a generalized - -accretive mapping with and
Proposition 1.
Let assumptions and hold for every , , and let be a generalized --accretive mapping with mappings and with if is satisfied for each , , where .
Proof.
Assume that there exists such that
If p is even: Since is a generalized --accretive mapping, then is -symmetric accretive with , and holds for each ; then, there exists such that
Since , and , it implies that . By (2), we have . Thus, . Similarly, we can prove the result when p is an odd number. This completes the proof. □
Theorem 1.
Let assumptions and hold for every , , and let be a generalized --accretive mapping with ; then, is single-valued.
Proof.
For any given , let . It follows that
If p is even: Since is -symmetric accretive with , we have
We proceed through the same process as that to obtain (4), and we have
Since , and , we have . It implies that . Thus, is single-valued. Similarly, we can prove the result when p is an odd number. This completes the proof. □
Definition 9.
Let assumptions and hold for , and let be a generalized --accretive mapping with . A proximal-point mapping is defined by
where ρ is a non-negative constant.
Now, we prove the Lipschitz continuity of the proximal-point mapping.
Theorem 2.
Let assumptions and hold for , and let be a generalized --accretive mapping with . Then, the proximal-point mapping is Δ-Lipschitz continuous, where
Proof.
Let and by Definition 9, we have
It follows that
Let and
If p is even: Since is -symmetric accretive with , we have
Let
We have
Hence,
that is,
where Similarly, we can prove the result when p is an odd number. This completes the proof. □
3. Set-Valued Variational Inclusions
Let Y be a q-uniformly smooth Banach space. For each , let be the mappings, be the single-valued mappings, and be a set-valued mapping. Let be a generalized --accretive mapping.
Now, the problem is to find such that
Special cases:
Problem (9) has been studied by Zou and Huang [9] when is an -accretive mapping. For the generalized m-accretive mapping, problem (9) was studied by Bi et al. [27].
Definition 10.
A set-valued mapping is said to be - Lipschitz continuous with , if
Theorem 3.
For any given , is a solution of (6) if and only if satisfies
where is a non-negative constant.
Proof.
Let be the solution of problem (6), we have
□
Algorithm 1.
For any given, we selectand obtain, , ,..., by the following iterative scheme
where n = 0,1,2,... and.
Theorem 4.
Let problem (6) hold with assumptions - and be a generalized --accretive mapping with . For each , we assume the following:
- (i)
- is --Lipschitz continuous;
- (ii)
- is -Lipschitz continuous with ;
- (iii)
- F is -strongly accretive with and in the -argument;
- (iv)
- F is -Lipschitz continuous in -argument;
- (v)
- in addition the following condition is satisfied:
Then, the iterative sequences developed by Algorithm 1 converge strongly to a solution to problem (6).
Proof.
From Algorithm 1 and Theorem 2, we have
By using the -Lipschitz continuity of , we have
By the -Lipschitz continuity of F and --Lipschitz continuity of , we have
Now, we compute
we have
Using Equations (13)–(16) in Equation (12), then Equation (12) becomes
which implies that
Let From (11), we have
Thus, we have . By (11), we have . This implies that as ; therefore, is a Cauchy sequence in Y. Then, there exists with . By the -Lipschitz continuity of and Algorithm 1, we have
It shows that are Cauchy sequences; then, there exists such that as . Now, we show that . Since , we have
Since is closed, . Similarly, we can prove . By continuity, we know that satisfy
Thus, problem (6) has the solution . □
Remark 1.
Let p be an even number. Let be a functional on Y; then, the vector , such that
where is finite for each , is known as the subgradient of f at z. The collections of all such subgradients of f at z holding (18) are known as the subdifferential of f at z. Let be set-valued mapping and consider the inclusion problem to find such that
Then, it turns out that is -strongly accretive, where , if is -symmetric accretive with , as the locally Lipschitz functionals on Y, and is -symmetric accretive with ; equivalently, we can state that is a generalized --accretive mapping. Now, all the assumptions of Theorem 4 hold, and one can easily find the solution to problem (19) by using Theorem 4.
4. Conclusions
In this article, we considered the generalized --accretive mappings defined on a product set, which contained the generalized --accretive mappings, -accretive mappings, and monotone mappings as special cases, since variational inclusions, generalized --accretive mappings, and proximal-point mappings have applications in physics, economics and management sciences. Therefore, we considered and studied a variational inclusion problem including a generalized --accretive mapping. We discussed the convergence criteria of an iterative algorithm to solve problem (6) under appropriate assumptions in q-uniformly smooth Banach spaces. In future, the results that are obtained for the proximal-point mapping associated with the generalized --accretive mappings conferred in this article can be continued to the Yosida inclusion problems in the setting of Banach spaces.
Author Contributions
Both the authors have equally contributed to the manuscript. All authors have read and agreed to the published version of the manuscript.
Funding
This research received no funding.
Institutional Review Board Statement
Not applicable.
Informed Consent Statement
Not applicable.
Data Availability Statement
Not applicable.
Acknowledgments
The authors sincerely thank the reviewers for their suggestions and helpful comments that led to the present form of the original manuscript.
Conflicts of Interest
The authors declare no conflict of interest.
Appendix A. Appendix of Example 2
For any , let
Thus, is -strongly accretive with . In a similar way, we can show that is -strongly accretive with for all .
For any , let
Thus, is -relaxed accretive with . In a similar way, we can show that is -relaxed accretive with for all .
For any , let
Thus, is -strongly accretive with . In a similar way, we can show that is -strongly accretive with for all .
For any , let
Thus, is -relaxed accretive with . In a similar way, we can show that is -relaxed accretive with for all .
Similarly, we can show that is -strongly accretive with for all and is -relaxed accretive with for all .
One can easily verify the following for :
Hence, is generalized -accretive with and .
References
- Fang, Y.-P.; Huang, N.-J. H-monotone operator and resolvent operator technique for variational inclusions. Appl. Math. Comput. 2003, 145, 795–803. [Google Scholar] [CrossRef]
- Hammad, H.A.; De la Sen, M. Shrinking projection Methods for accelerating relaxed inertial Tseng-type algorithm with applications. Math. Probl. Eng. 2020, 2020, 7487383. [Google Scholar] [CrossRef]
- Kazmi, K.R.; Khan, F.A.; Shahzad, M. A system of generalized variational inclusions involving generalized H(., .)-accretive mapping in real q-uniformly smooth Banach spaces. Appl. Math. Comput. 2011, 217, 9679–9688. [Google Scholar] [CrossRef]
- Lan, H.-Y.; Cho, Y.J.; Verma, R.U. Nonlinear relaxed cocoercive variational inclusions involving (A,η)-accretive mappings in Banach spaces. Comput. Math. Appl. 2006, 51, 1529–1538. [Google Scholar] [CrossRef]
- Peng, J.-W. On a new system of generalized mixed quasi-variational-like inclusions with (H,η)-accretive operators in real q-uniformly smooth Banach spaces. Nonlinear Anal. 2008, 68, 981–993. [Google Scholar] [CrossRef]
- Peng, J.-W.; Zhu, D.L. A new system of generalized mixed quasi-vatiational inclusions with (H,η)-monotone operators. J. Math. Anal. Appl. 2007, 327, 175–187. [Google Scholar] [CrossRef]
- Sun, J.; Zhang, L.; Xiao, X. An algorithm based on resolvent operators for solving variational inequalities in Hilbert spaces. Nonlinear Anal. (TMA) 2008, 69, 3344–3357. [Google Scholar] [CrossRef]
- Tuyen, T.M.; Hammad, H.A. Effect of shrinking projection and CQ-methods on two inertial forward–backward algorithms for solving variational inclusion problems. Rend. Circ. Mat. Palermo II Ser 2021, 70, 1669–1683. [Google Scholar] [CrossRef]
- Zou, Y.-Z.; Huang, N.-J. H(., .)-accretive operator with an application for solving variational inclusions in Banach spaces. Appl. Math. Comput. 2008, 204, 809–816. [Google Scholar] [CrossRef]
- Huang, N.-J.; Fang, Y.-P. Generalized m-accretive mappings in Banach spaces. J. Sichuan Univ. 2001, 38, 591–592. [Google Scholar]
- Zeng, L.C.; Guu, S.M.; Yao, J.C. Characterization of H-monotone operators with applications to variational inclusions. Comput. Math. Appl. 2005, 50, 329–337. [Google Scholar] [CrossRef]
- Zeng, L.C.; Guu, S.M.; Yao, J.C. An iterative method for generalized nonlinear set-valued mixed quasi-variational inequalities with H-monotone mappings. Comput. Math. Appl. 2007, 54, 476–483. [Google Scholar] [CrossRef]
- Zeng, L.C.; Guu, S.M.; Yao, J.C. Iterative approximation of solutions for a class of completely generalized set-valued quasi-variational inclusions. Comput. Math. Appl. 2008, 56, 978–987. [Google Scholar]
- Zou, Y.-Z.; Huang, N.-J. A new system of variational inclusions involving H(., .)-accretive operator in Banach spaces. Appl. Math. Comput. 2009, 212, 135–144. [Google Scholar] [CrossRef]
- Nazemi, S.Z. A new class of monotone mappings and a new class of variational inclusions in Banach spaces. J. Optimi. Theory Appl. 2012, 155, 785–795. [Google Scholar] [CrossRef]
- Guan, J.; Hu, C. A System of generalized variational inclusions involving a new monotone mapping in Banach Spaces. Abstr. Appl. Anal. 2013, 2013, 654537. [Google Scholar]
- Ahmad, R.; Dilshad, M.; Akram, M. Graph convergence for the H(., .)-co-accretive mapping with an application. Bull. Malays. Math. Sci. Soc. 2014, 38, 1481–1506. [Google Scholar] [CrossRef]
- Balooee, J.; Chang, S.; Wen, C. Generalized nearly asymptotically nonexpansive mappings and a system of generalized variational-like inclusions: Iterative method and approximation of common solutions. Ann. Funct. Anal. 2022, 13, 1–61. [Google Scholar] [CrossRef]
- Bhat, M.I.; Zahoor, B. Existence of solution and iterative approximation of a system of generalized variational-like inclusion problems in semi-inner product spaces. Filomat 2017, 31, 6051–6070. [Google Scholar] [CrossRef]
- Gupta, S.; Husain, S.; Mishra, V.N. Variational inclusion governed by αβ-H((., .), (., .))-mixed accretive mapping. Filomat 2017, 31, 6529–6542. [Google Scholar] [CrossRef]
- Gupta, S.; Singh, M. Variational-like inclusion involving infinite family of set-valued mapping governed by resolvent equations. J. Math. Comput. Sci. 2021, 10, 874–892. [Google Scholar]
- Gupta, S.; Singh, M. Generalized monotone mapping and resolvent equation techniques with an application. J. Math. Comput. Sci. 2021, 2, 1767–1783. [Google Scholar]
- Husain, S.; Gupta, S.; Mishra, V.N. Graph convergence for the H(., .)-mixed mapping with an application for solving the system of generalized variational inclusions. Fixed Point Theory Appl. 2013, 2013, 304. [Google Scholar] [CrossRef]
- Ram, T.; Iqbal, M. H(., ., ., .)-ϕ-η-cocoercive operator with an application to variational inclusions. Int. J. Nonlinear Anal. Appl. 2022, 13, 1311–1327. [Google Scholar]
- Xu, H.K. Inequalities in Banach spaces with applications. Nonlinear Anal. 1991, 16, 1127–1138. [Google Scholar] [CrossRef]
- Huang, N.-J. A new class of generalized set-valued implicit variational inclusions in Banach spaces with an application. Comput. Math. Appl. 2001, 41, 937–943. [Google Scholar] [CrossRef]
- Bi, Z.S.; Hart, Z.; Fang, Y.P. Sensitivity analysis for nonlinear variational inclusions involving generalized m-accretive mappings. J. Sichuan Univ. 2003, 40, 240–243. [Google Scholar]
Publisher’s Note: MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affiliations. |
© 2022 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/).