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This paper presents two new theorems on Geoffrion's properly efficient solutions and seven examples illustrating their applications to linear fractional vector optimization problems with unbounded constraint sets. Provided that all the components of the objective function are properly fractional, the first theorem gives sufficient conditions for the efficient solution set to coincide with the Geoffrion properly efficient solution set. Admitting that the objective function can have some affine components, in the second theorem we give sufficient conditions for an efficient solution to be a Geoffrion's properly efficient solution. The recession cone of the constraint set, the derivatives of the scalar objective functions, but no tangent cone to the constraint set at the efficient point, are used in the second theorem. [ABSTRACT FROM AUTHOR]

The purpose of this paper is to find a common element in the intersection of the set of zeros of the inclusion problem of sum of two monotone mappings and the set of fixed points of a Bregman quasi nonexpansive mapping in a reflexive Banach space by using Bregman distance and shrinking projection method. Under suitable conditions, some strong convergence theorems are proved. As applications, we utilize our results to study the convex minimization problem, variational inequality problem. [ABSTRACT FROM AUTHOR]

First-order methods such as proximal gradient, which use Forward–Backward Splitting techniques have proved to be very effective in solving nonsmooth convex minimization problem, which is useful in solving various practical problems in different fields such as machine learning and image processing. In this paper, we propose few new forward–backward splitting algorithms, which consume less number of iterations to converge to an optimum. In addition, we derive convergence rates for the proposed formulations and show that the speed of convergence of these algorithms is significantly better than the traditional forward–backward algorithm. To demonstrate the practical applicability, we apply them to two real-world problems of machine learning and image processing. The first issue deals with the regression on high-dimensional datasets, whereas the second one is the image deblurring problem. Numerical experiments have been conducted on several publicly available real datasets to verify the obtained theoretical results. Results demonstrate the superiority of our algorithms in terms of accuracy, the number of iterations required to converge and the rate of convergence against the classical first-order methods. [ABSTRACT FROM AUTHOR]

A parametric constrained convex optimal control problem, where the initial state is perturbed and the linear state equation contains a noise, is considered in this paper. Formulas for computing the subdifferential and the singular subdifferential of the optimal value function at a given parameter are obtained by means of some recent results on differential stability in mathematical programming. The computation procedures and illustrative examples are presented. [ABSTRACT FROM AUTHOR]

By a scalarization method and properties of semi-algebraic sets, it is proved that both the Pareto solution set and the weak Pareto solution set of a vector variational inequality, where the constraint set is polyhedral convex and the basic operators are given by polynomial functions, have finitely many connected components. Consequences of the results for vector optimization problems are discussed in details. The results of this paper solve in the affirmative some open questions for the case of general problems without requiring monotonicity of the operators involved. [ABSTRACT FROM AUTHOR]

The problem of finding minima of weakly sequentially lower semicontinuous functions on reflexive Banach spaces is studied by means of convex and nonconvex subdifferentials. Finding a descent direction for a non-stationary point is a question of importance for many optimization algorithms. The existence or non-existence of such a direction is clarified through several theorems and a series of selective examples. For the general problem, a notion called radius of descent is proposed and shown to be useful for the analysis related to descent directions. [ABSTRACT FROM AUTHOR]

By using a scalarization method and some properties of semi-algebraic sets, we prove that both the proper Pareto solution set and the weak Pareto solution set of a vector variational inequality, where the convex constraint set is given by polynomial functions and all the components of the basic operators are polynomial functions, have finitely many connected components, provided that the Mangasarian-Fromovitz constraint qualification is satisfied at every point of the constraint set. In addition, if the proper Pareto solution set is dense in the Pareto solution set, then the latter also has finitely many connected components. Consequences of the results for vector optimization problems are discussed in detail. [ABSTRACT FROM AUTHOR]

Introduction Juvenile Idiopathic Arthritis (JIA) is a group of conditions characterized by chronic inflammatory joint disease of unknown aetiology before the age of 16. This joint damage is complicated by joint deformities, amplitude limitations, muscle imbalances causing a reduction in the functional capacities of the child. The delayed diagnosis, the inaccessibility of biotherapies give rise to deformations which hinder the development of the physical capacities and the social, educational and then professional integration of the child. Objective Sensitize practitioners about early diagnosis and multidisciplinary management of JIA, in order to avoid severe deformities. Observation A 17-year-old girl, out of school, was admitted to a rheumatology unit for the evolution of chronic polyarthralgia with transient skin eruption evolving by inflammatory attack with partial remission since the age of 8 years. There was no notable story. On physical examination, the affected joints were painful. Deformities were observed such as valgus of the knees and forefeet, ulnar deviation of the wrists and nonspecific of the fingers (Figs. 1 and 2). The biological inflammatory syndrome was present with (CRP 90 mg/l, VS 48 mm/h) and a blood count (Hb 12.5 g/dl, Plq 205 000/μL, GB 14. 109/l). Serum ferritin was elevated at 197.7 μg/ml. The other assessments in particular (blood cultures, FAN, FR, blood smears) came back negative. The diagnosis of AJI in systemic form was retained. The X-ray showed osteoarticular destruction with fixed exostoses, Larsen's stage 4 (Figs. 3 and 4) and Steinbrocker's stage 3 with minimal functional capacity. The treatment included an NSAID (ibuprofen at 40 mg/kg/day), followed by corticosteroid therapy (Prednisolone at a dose of 1 mg/kg/day) and as background treatment methotrexate (10 mg/week). evolution at 3 months was favorable on the pain. The management of the deformities was the subject of a multidisciplinary consultation meeting (physiotherapists, rheumatologists, orthopedic surgeons and paediatricians) very expensive for the parents. Thus it benefited a physical treatment made up of joint maintenance physiotherapy and equipment for joints that are still mobile. E59 Figures 1 and 2 Open in new tab Download slide E59 Figures 3 and 4 Open in new tab Download slide Discussion In Africa, osteoarticular pathology in children most often evokes diagnoses of sickle cell disease and acute articular rheumatism. From the first symptoms, children are referred to traditional healers, especially in rural areas where there is no specialist, then to pediatrics [1]. These reasons could explain the long delay in diagnosis as in the patient whose delay was 9 years. The diagnostic age of our patient was 17 years, higher than elsewhere [2] but consistent with the results of Diomandé in Abidjan with an average delay of 10 years [3]. Most studies find a female predominance with an age of onset between 4 and 8 years [4, 5]. In our patient, the involvement was polyarticular from the outset and the FRs were negative, as in most studies [1, 3]. The presence of these deformities was a source of significant handicap in our patient, which led to her dropping out of school, as stipulated in the literature. In first intention, we used NSAIDs, however unsatisfactory. Faced with the persistence of pain, she received prednisolone at 1 mg/kg/d favorable. As basic treatment she received methotrexate, biotherapies being inaccessible in our context because of their high cost. The management of deformities was the subject of a multidisciplinary consultation meeting (physiotherapists, rheumatologists, orthopedic surgeons and paediatricians) whose costs were beyond the reach of indigent parents. Conclusion The diagnosis and the multidisciplinary treatment must be early and continuous of the disease in order to avoid the deformations, which once installed are irreversible. References 1. V. Weber, L. Goffin, A. Kolivras, C. Adler and G. Casimir. An atypical case of systemic juvenile idiopathic arthritis: Rev Med Brux 2017; 38: 511–4 2. Diomandé M, Coulibaly AK, Kouakou ESCL, Yao JC. Profile of Juvenile Idiopathic Arthritis Observed in Abidjan (Côte d'Ivoire): A Report about 17 Cases. British Journal of Medicine & Medical Research. 2016; 16 (11): 1–6 3. Chkirate B, Jabouril F, Aïtouamar H, Rouiti A et al. Juvenile idiopathic arthritis (about 70 cases). Medical hope. 2001; 8: 256–260 4. Juvenile idiopathic arthritis—Focus on Disability/Orphanet Disability Encyclopedia www.orpha.net/data/patho/Han/Int/fr/ArthriteJuvenileIdiopathique%5fFR%5ffr%5fHAN%5fORPHA92.pdf | January 2018 5. F. Beltramo, Claude Gavillot, Irène Lemelle, Danièle Sommelet. Physical Medicine and Rehabilitation in Juvenile Idiopathic Arthritis: Rheumatism Review 70 (2003) 507–510 Conflict of interest None [ABSTRACT FROM AUTHOR]

Linear fractional vector optimization problems are special non-convex vector optimization problems. They were introduced and first studied by E.U. Choo and D.R. Atkins in the period 1982–1984. This paper investigates the properness in the sense of Geoffrion of the efficient solutions of linear fractional vector optimization problems with unbounded constraint sets. Sufficient conditions for an efficient solution to be Geoffrion's properly efficient solution are obtained via Benson's characterization [An improved definition of proper efficiency for vector maximization with respect to cones. J Math Anal Appl. 1979;71:232–241] of Geoffrion's proper efficiency. [ABSTRACT FROM AUTHOR]

In this paper, without using any regularity assumptions, we derive a new exact formula for computing the Fréchet coderivative and an exact formula for the Mordukhovich coderivative of normal cone mappings to perturbed polyhedral convex sets. Our development establishes generalizations and complements of the existing results on the topic. An example to illustrate formulae is given. [ABSTRACT FROM AUTHOR]

This paper is devoted to the study of the stability of the solution map for the parametric convex semi-infinite optimization problem under convex function perturbations in short, PCSI. We establish sufficient conditions for the pseudo-Lipschitz property of the solution map of PCSI under perturbations of both objective function and constraint set. The main result obtained is new even when the problems under consideration reduce to linear semi-infinite optimization. Examples are given to illustrate the obtained results. [ABSTRACT FROM AUTHOR]

By using a stability theorem of S.M. Robinson and a scalarization method, we establish sufficient conditions for the upper semicontinuity of the solution maps of parametric monotone affine vector variational inequalities. As a by-product, some new topological properties of the solution sets of these problems are obtained. Our results imply several facts for the solution stability and connectedness of the solution sets of convex quadratic vector optimization problems and of linear fractional vector optimization problems. [ABSTRACT FROM AUTHOR]

This paper deals with the generalized Clarke epiderivative of the extremum (or efficient point) multifunction in parametric vector optimization problems. The formulas for computing and/or estimating the generalized Clarke epiderivative of this extremum multifunction are given in terms of the Clarke tangent cone to the graph of a multifunction or the constraint mapping and/or the Fréchet derivative of the objective function. An application to semi-infinite programming is given. [ABSTRACT FROM AUTHOR]

Abstract: By constructing some suitable examples, Jeyakumar and Yen (2004)  have shown that the Robinson metric regularity (Rmr) and the Lipschitz-like property (Llp) of implicit multifunctions are not equivalent. This paper clarifies relationships between the two properties of implicit multifunctions. It turns out that the (reasonable) sufficient conditions for having (Rmr) (Llp) are quite different from those for the validity of the reverse implication. The implicit function theorem due to Yen and Yao (2009) serves as a tool for our analysis of (Rmr) and (Llp). [Copyright &y& Elsevier]

Abstract: We obtain some point-based sufficient conditions for the metric regularity in Robinson’s sense of implicit multifunctions in a finite-dimensional setting. The new implicit function theorem (which is very different from the preceding results of Ledyaev and Zhu [Yu.S. Ledyaev, Q.J. Zhu, Implicit multifunctions theorems, Set-Valued Anal. 7 (1999) 209–238], Ngai and Théra [H.V. Ngai, M. Théra, Error bounds and implicit multifunction theorem in smooth Banach spaces and applications to optimization, Set-Valued Anal. 12 (2004) 195–223], Lee, Tam and Yen [G.M. Lee, N.N. Tam, N.D. Yen, Normal coderivative for multifunctions and implicit function theorems, J. Math. Anal. Appl. 338 (2008) 11–22]) can be used for analyzing parametric constraint systems as well as parametric variational systems. Our main tools are the concept of normal coderivative due to Mordukhovich and the corresponding theory of generalized differentiation. [Copyright &y& Elsevier]

Combination chemotherapy results in a significant survival advantage in patients with advanced gastric cancer compared to best supportive care. Nevertheless, the prognosis remains poor with a median survival of 8–10 months. Topoisomerase-I inhibitors such as irinotecan have activity in advanced gastric cancer. Pegamotecan may offer significant advantages over other topoisomerase-I inhibitors due to its prolonged circulating half-life, tolerability and passive tumour accumulation. This was a non-randomised, multi-centre, two-step Fleming design phase II study. Eligible patients with locally advanced (inoperable) or metastatic gastric or gastro-oesophageal adenocarcinoma, with measurable disease, ECOG performance status ≤2, with adequate haematological, renal and hepatic function, who had received ≤1 prior chemotherapy regimen for advanced disease, were treated with 7,000 mg/m2 of pegamotecan as a 1-h infusion every 21 days until disease progression or unacceptable toxicity. The primary efficacy measure was the objective response rate. Five of the 35 patients recruited into this study had a partial response (14.3%), with a median time to progression of 11.9 weeks (95% CI: 6.6, 13.1), and median overall survival of 38.1 weeks (95% CI: 29.0, 47.3). Grade 3/4 toxicities included neutropenia in 6 (17.1%) patients, thrombocytopenia in 4 (11.4%), fatigue in 8 (22.9%), nausea in 6 (17%), vomiting in 6 (17%) and anorexia in 4 (11.4%) patients. There were no episodes of febrile neutropenia and no toxic deaths. Pegamotecan has activity in this patient population and was generally well-tolerated. The favourable rate of haematological toxicities and diarrhoea compared with irinotecan in similar studies suggests that pegamotecan could be combined with other active agents in further studies in this disease. [ABSTRACT FROM AUTHOR]

Abstract: Let be a reflexive and smooth real Banach space which has a weakly sequentially continuous duality mapping. In this paper, we consider the following viscosity approximation scheme (where is a generalized contraction mapping) for infinitely many nonexpansive self-mappings in . We establish a strong convergence result which generalizes some results in the literature. [Copyright &y& Elsevier]

We extend some results due to Thanh-Hao (Acta Math. Vietnam. 31: 283-289, 2006) and Noor (J. Optim. Theory Appl. 115:447-452, 2002). The first paper established a convergence theorem for the Tikhonov regularization method (TRM) applied to finite-dimensional pseudomonotone variational inequalities (VIs), answering in the affirmative an open question stated by Facchinei and Pang (Finite- Dimensional Variational Inequalities and Complementarity Problems, Springer, New York, 2003). The second paper discussed the application of the proximal point algorithm (PPA) to pseudomonotone VIs. In this paper, new facts on the convergence of TRM and PPA (both the exact and inexact versions of PPA) for pseudomonotone VIs in Hilbert spaces are obtained and a partial answer to a question stated in (Acta Math. Vietnam. 31:283-289, 2006) is given. As a byproduct, we show that the convergence theorem for inexact PPA applied to infinite-dimensional monotone variational inequalities can be proved without using the theory of maximal monotone operators. [ABSTRACT FROM AUTHOR]

We discuss the lower semicontinuity of the set of efficient solutions for parametric generalized systems with monotone bifunctions in real locally convex Hausdorff topological vector spaces. [ABSTRACT FROM AUTHOR]

We introduce the concept of positive proper efficient solutions to the generalized system in this paper. We show that, under some suitable conditions, the set of positive proper efficient solutions is dense in the set of efficient solutions to the generalized system. We discuss also the connectedness of the set of efficient solutions for the generalized system with monotone bifunctions in real locally convex Hausdorff topological vector spaces. [ABSTRACT FROM AUTHOR]

Abstract: We obtain equivalences among the covering property at a positive-order rate of a multifunction, the metric regularity property of a positive order, and the Hölder-like continuity property of the inverse mapping. Our results develop some aspects of the preceding results of J.-P. Penot, J.M. Borwein and D.M. Zhuang, H. Frankowska, B.S. Mordukhovich, and L.I. Minchenko. Necessary conditions for having these properties are given in terms of positive-order variational coderivative, a concept used here for the first time. We also discuss some known sufficient conditions for the validity of the three properties in terms of the positive-order variation in the sense of H. Frankowska. Illustrative examples are considered. [Copyright &y& Elsevier]

In this paper, we investigate the strong convergence of an inexact proximalpoint algorithm. It is known that the proximal-point algorithm converges weakly to a solution of a maximal monotone operator, but fails to converge strongly. Solodov and Svaiter (Math. Program. 87:189–202, 2000) introduced a new proximal-type algorithm to generate a strongly convergent sequence and established a convergence result in Hilbert space. Subsequently, Kamimura and Takahashi (SIAM J. Optim. 13:938–945, 2003) extended the Solodov and Svaiter result to the setting of uniformly convex and uniformly smooth Banach space. On the other hand, Rockafellar (SIAM J. Control Optim. 14:877–898, 1976) gave an inexact proximal-point algorithm which is more practical than the exact one. Our purpose is to extend the Kamimura and Takahashi result to a new inexact proximal-type algorithm. Moreover, this result is applied to the problem of finding the minimizer of a convex function on a uniformly convex and uniformly smooth Banach space. [ABSTRACT FROM AUTHOR]

In this paper, by employing the notion of generalized projection operators and the well-known Fan's lemma, we establish some existence results for the variational inequality problem and the quasivariational inequality problem in reflexive, strictly convex, and smooth Banach spaces. We propose also an iterative method for approximate solutions of the variational inequality problem and we establish some convergence results for this iterative method. [ABSTRACT FROM AUTHOR]

The auxiliary principle technique is extended to develop an iterative algorithm for finding approximate solutions of a mixed variational-like inequality in a real Hilbert space. Not only the existence of approximate solutions of a mixed variational-like inequality is proven, but also the strong convergence of approximate solutions to an exact solution of a mixed variational-like inequality is shown. The convergence criteria presented in this article are new. [ABSTRACT FROM AUTHOR]

In this paper, we study a class of general monotone equilibrium problems in a real Hilbert space which involves a monotone differentiable bifunction. For such a bifunction, a skew-symmetric type property with respect to the partial gradients is established. We suggest to solve this class of equilibrium problems with the modified combined relaxation method involving an auxiliary procedure. We prove the existence and uniqueness of the solution to the auxiliary variational inequality in the auxiliary procedure. Further, we prove also the weak convergence of the modified combined relaxation method by virtue of the monotonicity and the skew-symmetric type property. [ABSTRACT FROM AUTHOR]

This paper introduces an iterative method for finding approximate solutions of a set-valued mixed quasivariational inequality in the setting of a Banach space. Existence of a solution of this rather general problem and the convergence of the proposed iterative method to a solution are established. [ABSTRACT FROM AUTHOR]

In this paper, we consider an implicit quasivariational inequality without continuity assumptions in normed spaces. The main result (Theorem 2.1) provides an infinite-dimensional version of Theorem 3.2 in Ref. 1. To achieve such a goal, we employ Theorem 3.2 in Ref. 1 and the technique of Cubiotti in Ref. 2. In particular, Theorem 3.1 covers a recent result of Cubiotti (Theorem 3.1 of Ref. 2) as a special case. [ABSTRACT FROM AUTHOR]

By applying the maximal element theorems on product of G-convex spaces due to the first author, some equilibrium existence theorems for generalized games with fuzzy constraint correspondences are proved in G-convex spaces. As applications, some existence theorems of solutions for the system of generalized vector quasiequilibrium problems are established in noncompact product of G-convex spaces. Our results improve and generalize some recent results in the literature to product of G-convex spaces. [ABSTRACT FROM AUTHOR]

Let Z and X be Hausdorff real topological vector spaces and let Lb(X, Z) be the space of continuous linear mappings from X into Z equipped with the topology of bounded convergence. In this paper, we define the (S)+ condition for operators from a nonempty subset of X into Lb(X, Z) and derive some existence results for vector variational inequalities with operators of the class (S)+. Some applications to vector complementarity problems are given. [ABSTRACT FROM AUTHOR]

In this paper, four extragradient-type algorithms are presented for solving bilevel variational inequalities of pseudomonotone and non-Lipschitz continuous operators in real Hilbert spaces. The proposed iterative schemes employ two Armijo-type linesearch methods making them work adaptively. Strong convergence theorems of the suggested algorithms are established under some mild conditions. Finally, some numerical experiments and applications are given to verify the advantages and efficiency of the proposed algorithms over some previously known ones. [ABSTRACT FROM AUTHOR]

In the present paper, differential inclusions with a causal multioperator are considered. We apply the method of nonsmooth integral guiding potentials to the study of the problem on the asymptotic behaviour of solutions for such inclusions. We investigate both the case of a closed and convex-valued right-hand part and the case of a nonconvex-valued and lower semicontinuous right-hand part. [ABSTRACT FROM AUTHOR]

In a real Hilbert space, let the GSVI and CFPP represent a general system of variational inclusions and a common fixed point problem of countable nonexpansive mappings and an asymptotically nonexpansive mapping, respectively. In this paper, via a new inertial subgradient extragradient rule we introduce and analyze two iterative algorithms for solving the monotone bilevel equilibrium problem (MBEP) with the GSVI and CFPP as constraints. Some strong convergence theorems for the proposed algorithms are established under some mild assumptions. Our results improve and extend some corresponding results in the earlier and very recent literature. [ABSTRACT FROM AUTHOR]

In this paper we propose a parallel iterative hybrid methods for finding a common element of the solution sets of a finite family of pseudomonotone equilibrium problems and the fixed points set of a semigroup-nonexpensive mappings in Hilbert spaces. Under mild conditions, we obtain the strong convergence of the proposed iterative process. Some numerical experiments are given to verify the efficiency the proposed algorithm. [ABSTRACT FROM AUTHOR]

This paper deals with the necessary optimality conditions for semilinear elliptic optimal control problems with a pure pointwise state constraint and mixed pointwise constraints. By computing the so-called ‘sigma-term’, we obtain the second-order necessary optimality conditions for the problems, which is sharper than some previously established results in the literature. Besides, we give a condition which relaxes the Slater condition and guarantees that the Lagrangian is normalized. [ABSTRACT FROM AUTHOR]

The Mann iterates behave well for nonexpansive mappings for any initial guess in the domain. Our aim in this article is to extend this method to a broad class of inexact fixed point algorithms generated by nearly nonexpansive sequences in Banach spaces and to locate the weak limit of the iterates by its initial guesses. Due to the inexactness, our algorithms become efficiently applicable for a wider class of problems. As applications, we give convergence theorems for finding solutions of variational inclusion problems and constrained multiple-sets split feasibility problems. Our results are significant refinements and improvements of the corresponding results in the literature. [ABSTRACT FROM AUTHOR]

In the present paper, we study the finite termination of sequences generated by inexact proximal point algorithms for finding zeroes of a maximal monotone (set-valued) operator $$T$$ on a Hilbert space. Under some mild conditions, we get that a sequence generated by inexact proximal point algorithm stops after a finite number of iterations. Our results extend the corresponding results in Rockafellar (SIAM J Control Optim 14:877-898, ). In particular, for optimization problems, our results improve corresponding results in Ferris (Math Progr 50:359-366, ). As applications, we obtain finite termination of projected gradient method. [ABSTRACT FROM AUTHOR]

In this paper, we study second-order necessary optimality conditions for a discrete optimal control problem with a nonconvex cost function and control constraints. By establishing an abstract result on second-order necessary optimality conditions for a mathematical programming problem, we derive second-order optimality conditions for a discrete optimal control problem. [ABSTRACT FROM AUTHOR]

A new inclusion problem is introduced using generalized Cayley operator and we call it Cayley inclusion problem. We also study its corresponding resolvent equation problem. By using a generalized resolvent operator and generalized Yosida approximation operator, first we establish a fixed point formulation for Cayley inclusion problem. An algorithm is defined to find the solution of Cayley inclusion problem. An existence and convergence result is proved. Secondly, we have shown the equivalence of Cayley inclusion problem with a resolvent equation. We define an iterative algorithm with some of its equivalent forms for solving resolvent equation problem. A numerical example is constructed and a convergence graph is shown by using MATLAB program. [ABSTRACT FROM AUTHOR]

We propose implicit and explicit iterative algorithms for finding a common element of the set of solutions of the minimization problem for a convex and continuously Fréchet differentiable functional, the set of solutions of a finite family of generalized mixed equilibrium problems, and the set of solutions of a finite family of variational inequalities for inverse strong monotone mappings in a real Hilbert space. We prove that the sequences generated by the proposed algorithms converge strongly to a common element of three sets, which is the unique solution of a variational inequality defined over the intersection of three sets under very mild conditions. [ABSTRACT FROM AUTHOR]

The aim of this paper is to define a generalized monotone mapping, which is the sum of symmetric cocoercive mapping and symmetric monotone mapping. The resolvent operator associated with generalized monotone mapping is defined and some of its properties are shown. We solve a variational inclusion problem using these new concepts. For illustration, some examples are given. [ABSTRACT FROM AUTHOR]

We suggest and analyze relaxed extragradient iterative algorithms with regularization for finding a common element of the solution set of a general system of variational inequalities, the solution set of a split feasibility problem, and the fixed point set of a strictly pseudocontractive mapping defined on a real Hilbert space. Here the relaxed extragradient methods with regularization are based on the well-known successive approximation method, extragradient method, viscosity approximation method, regularization method, and so on. Strong convergence of the proposed algorithms under some mild conditions is established. Our results represent the supplementation, improvement, extension, and development of the corresponding results in the very recent literature. [ABSTRACT FROM AUTHOR]

In this paper, we introduce and study a mixed variational inclusion problem involving infinite family of fuzzy mappings. An iterative algorithm is constructed for solving a mixed variational inclusion problem involving infinite family of fuzzy mappings and the convergence of iterative sequences generated by the proposed algorithm is proved. Some illustrative examples are also given. [ABSTRACT FROM AUTHOR]

In this article, we consider a monotone variational inequality with variational inequality constraint over the set of fixed points of a nonexpansive mapping, which is called a triple-hierarchical variational inequality (THVI). A relaxed hybrid steepest-descent method with variable parameters is introduced for solving the THVI. Strong convergence of the method to a unique solution of the THVI is studied under certain assumptions. We also investigate another monotone variational inequality with the variational inequality constraint over the set of common fixed points of a finite family of nonexpansive mappings, and present an iterative algorithm for solving such kind of problems. It is proven that under mild conditions the sequence generated by the proposed algorithm converges strongly to a unique solution of later problem. [ABSTRACT FROM AUTHOR]

Abstract: The purpose of this paper is to introduce and analyze an extragradient method with regularization for finding a common element of the solution set of the split feasibility problem and the set of fixed points of a nonexpansive mapping in the setting of infinite-dimensional Hilbert spaces. Combining the regularization method and the extragradient method due to Nadezhkina and Takahashi [N. Nadezhkina, W. Takahashi, Weak convergence theorem by an extragradient method for nonexpansive mappings and monotone mappings, J. Optim. Theory Appl. 128 (2006) 191–201], we propose an iterative algorithm for finding an element of . We prove that the sequences generated by the proposed algorithm converge weakly to an element of under mild conditions. [Copyright &y& Elsevier]

We study in this paper the existence and the approximation of solutions of variational inequalities involving generalized pseudocontractive mappings in Banach spaces. The convergence analysis of a proposed hybrid iterative method for approximating common zeros or fixed points of a possibly infinitely countable or uncountable family of such operators will be conducted within the conceptual framework of the "viscosity approximation technique" in reflexive Banach spaces with uniform Gâteaux differentiable norms. This technique should make existing or new results in solving variational inequalities more applicable. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, we consider the split feasibility problem (SFP) in infinite-dimensional Hilbert spaces, and study the relaxed extragradient methods for finding a common element of the solution set of SFP and the set of fixed points of a nonexpansive mapping . Combining Mann’s iterative method and Korpelevich’s extragradient method, we propose two iterative algorithms for finding an element of . On one hand, for , the identity mapping, we derive the strong convergence of one iterative algorithm to the minimum-norm solution of the SFP under appropriate conditions. On the other hand, we also derive the weak convergence of another iterative algorithm to an element of under mild assumptions. [Copyright &y& Elsevier]

This paper presents an exact formula for computing the normal cones of the constraint set mapping including the Clarke normal cone and the Mordukhovich normal cone in infinite programming under the extended Mangasarian-Fromovitz constraint qualification condition. Then, we derive an upper estimate as well as an exact formula for the limiting subdifferential of the marginal/optimal value function in a general Banach space setting. [ABSTRACT FROM AUTHOR]

Abstract: The present paper is divided into two parts. In the first part, we introduce implicit and explicit iterative schemes for finding the fixed point of a nonexpansive mapping defined on the closed convex subset of a real Hilbert space. We establish results on the strong convergence of the sequences generated by the proposed schemes to a fixed point of a nonexpansive mapping. Such a fixed point is also a solution of a variational inequality defined on the set of fixed points. In the second part, we propose implicit and explicit iterative schemes for finding the approximate minimizer of a constrained convex minimization problem and prove that the sequences generated by our schemes converge strongly to a solution of the constrained convex minimization problem. Such a solution is also a solution of a variational inequality defined over the set of fixed points of a nonexpansive mapping. The results of this paper extend and improve several results presented in the literature in the recent past. [Copyright &y& Elsevier]

In this article, we establish a collectively fixed point theorem and a maximal element theorem for a family of multivalued maps in the setting of topological semilattice spaces. As an application of our maximal element theorem, we prove the existence of solutions of generalized abstract economies with two constraint correspondences. We consider the system of (vector) quasi-equilibrium problems (in short, (S(V)QEP)) and system of generalized vector quasi-equilibrium problems (in short, (SGVQEP)). We first derive the existence result for a solution of (SQEP) and then by using this result, we prove the existence of a solution of system of a generalized implicit quasi-equilibrium problems. By using existence result for a solution of (SQEP) and weighted sum method, we derive an existence result for solutions of (SVQEP). By using our maximal element theorem, we also establish some existence results for the solutions of (SGVQEP). Some applications of our results to constrained Nash equilibrium problem for vector-valued functions with infinite number of players and to semi-infinite problems are also given. [ABSTRACT FROM AUTHOR]