some common fixed point theorems for mappings and multi valued mappings using certain weak conditions of commutativity we prove some common fixed point theorems in complete metrically convex spaces which in turn generalize results due to assad and kirk itoh khan and several others

contractive type non self mappings on metric spaces of hyperbolic type abstract let x d be a metric space of hyperbolic type and k a nonempty closed subset of x in this paper we study a class of mappings from k into x not necessarily self mappings on k which are defined by the contractive condition 2 1 below and a class of pairs of mappings from k into x which satisfy the condition 2 28 below we present fixed point and common fixed point theorems which are generalizations of the corresponding fixed point theorems of ciric l b ciric quasi contraction non self mappings on banach spaces bull acad serbe sci arts 23 1998 25 31 l b ciric j s ume m s khan h k t pathak on some non self mappings math nachr 251 2003 28 33 rhoades b e rhoades a fixed point theorem for some non self mappings math japon 23 1978 457 459 and many other authors some examples are presented to show that our results are genuine generalizations of known results from this area

a common fixed point theorem for compatible quasi contractive self mappings in metric spaces a common fixed point theorem for weakly commuting quasi contractive self mappings with contracting orbital diameters in metric spaces v berinde a common fixed point theorem for quasi contractive type mappings ann univ sci budapest 46 2003 81 90 is extended to the more general class of compatible quasi contractive self mappings our result does extend and generalize numerous related results in literature

common fixed points for maps on cone metric space the purpose of this paper is to generalize and to unify fixed point theorems of das and naik ciric jungck huang and zhang on complete cone metric space

fixed point theorem of generalized quasi contractive mapping in cone metric space abstract in this paper we introduce the generalized quasi contractive mapping f in a cone metric space x d f is called a generalized quasi contractive if there is a real 0 1 such that for all x y x d f x f y s for some s c o 0 d f x f y d x y d x f x d y f y d x f y d y f x it is proved that if x is a complete cone metric space with normal cone then f has a unique fixed point a example is given which shows that our result is a genuine generalization of quasi contractive mapping

fixed point theorems for set valued contractions in complete metric spaces abstract the fixed point theory of set valued contractions which was initiated by nadler s b nadler jr multi valued contraction mappings pacific j math 30 1969 475 488 was developed in different directions by many authors in particular by s reich fixed points of contractive functions boll unione mat ital 5 1972 26 42 n mizoguchi w takahashi fixed point theorems for multivalued mappings on complete metric spaces j math anal appl 141 1989 177 188 y feng s liu fixed point theorems for multi valued contractive mappings and multi valued caristi type mappings j math anal appl 317 2006 103 112 in the present paper the concept of contraction for set valued maps in metric spaces is introduced and the conditions guaranteeing the existence of a fixed point for such a contraction are established one of our results essentially generalizes the nadler and feng liu theorems and is different from the mizoguchi takahashi result the second result is different from the reich and mizoguchi takahashi results the method used in the proofs of our results is inspired by mizoguchi takahashi and feng liu s ideas comparisons and examples are given

on fuzzy measure and fuzzy integral on fuzzy set abstract on a fuzzy algebra of fuzzy sets we discuss some structural characteristics of a fuzzy measure the pseudo autocontinuity and some other concepts for a fuzzy measure are introduced and the relations between these cre discussed for the case of fuzzy sets riesz s theorems and lebesgue s theorems for a sequence of measurable functions are proved the concept of the fuzzy integral on a fuzzy set is given and some properties of fuzzy integrals on fuzzy sets are studied finally we prove some convergence theorems of a sequence of fuzzy integrals on fuzzy sets

some common fixed point theorems for a family of mappings in metrically convex spaces abstract in the present paper some common fixed point theorems for a sequence and a pair of nonself mappings in complete metrically convex metric spaces are proved which generalize such results due to khan et al m s khan h k pathak m d khan some fixed point theorems in metrically convex spaces georgian math j 7 3 2000 523 530 assad n a assad on a fixed point theorem of kannan in banach spaces tamkang j math 7 1976 91 94 chatterjea s k chatterjea fixed point theorems c r acad bulgare sci 25 1972 727 730 and several others some related results are also discussed

some equivalent formulations of the generalized ekeland s variational principle and their applications abstract in this paper we first give a generalized takahashi s existence theorem from the existence theorem we establish some equivalence relations between generalized caristi s fixed point theorems and generalized ekeland s variational principles some applications to the existence theorems of weak sharp minima and global error bounds for lower semicontinuous functions are also given

common fixed points for g f type maps in cone metric spaces abstract in this paper we study common fixed points for the self and non self g f type maps in cone metric spaces our main results are related to the cases when g is f quasi contraction in a sense of das and naik and the cone need not be normal these results generalize several well known comparable results in the literature

on common fixed point theorems for non self hybrid mappings in convex metric spaces abstract in this paper we introduce the concept of a contractive type non self mappings for a two pair of multi valued and single valued mappings in metric spaces and prove some results on coincidence and common fixed points in complete convex metric spaces our theorems generalize and improve the theorems of imdad and khan m imdad l khan some common fixed point theorems for a family of mappings in metrically convex spaces nonlinear anal theor 67 9 2007 2717 2726 m imdad l khan fixed point theorems for a family of hybrid pairs of mappings in metrically convex spaces fixed point theory appl 2005 3 2005 281 294 and of assad n a assad fixed point theorems for set valued transformations on compact sets boll un math ital 4 1973 1 7 and several others theorems to accomplish that we shall use slightly improved version of methods of proofs usually used in proving fixed point theorems for non self mappings an example is constructed to show that our results are genuine generalizations of the above mentioned results

rhoades type fixed point theorems for a pair of nonself mappings abstract using suitable conditions of weak commutativity we prove theorems for a pair of nonself mappings which generalize earlier results due to rhoades and assad et al some illustrative examples and applications are also discussed

on lagrangian schemes for porous medium type generalized diffusion equations a discrete energetic variational approach abstract in this paper we present a systematic framework to derive a variational lagrangian scheme for porous medium type generalized diffusion equations by employing a discrete energetic variational approach such discrete energetic variational approaches are analogous to energetic variational approaches 39 25 in a semidiscrete level which provide a basis of deriving the semi discrete equations and can be applied to a large class of partial differential equations with energy dissipation laws and kinematic relations the numerical schemes derived by this framework can inherit the variational structure from the continuous energy dissipation law as an illustration we develop two variational lagrangian schemes for the multidimensional porous medium equations pme based on two different energy dissipation laws we focus on the numerical scheme based on the energy dissipation law with 1 2 u 2 d x as the dissipation functional several numerical experiments demonstrate the accuracy of this scheme as well as its ability in capturing the free boundary and estimating the waiting time for the pme in both 1d and 2d

mizoguchi takahashi s type fixed point theorem recently eldred a a eldred j anuradha p veeramani on equivalence of generalized multi valued contactions and nadler s fixed point theorem j math anal appl 2007 doi 10 1016 j jmaa 2007 01 087 claimed that nadler s s b nadler jr multivalued contraction mappings pacific j math 30 1969 475 488 fixed point theorem is equivalent to mizoguchi takahashi s n mizoguchi w takahashi fixed point theorems for multivalued mappings on complete metric space j math anal appl 141 1989 177 188 fixed point theorem very recently suzuki t suzuki mizoguchi takahashi s fixed point theorem is a real generalization of nadler s j math anal appl 2007 doi 10 1016 j jmaa 2007 08 022 produced an example to disprove their claim and showed that mizoguchi takahashi s fixed point theorem is a real generalization of nadler s fixed point theorem we refine generalize mizoguchi takahashi s fixed point theorem our result improves a recent result by klim and wadowski d klim d wardowski fixed point theorems for set valued contractions in complete metric spaces j math anal appl 334 1 2007 132 139 and extends hicks and rhoades t l hicks b e rhoades a banach type fixed point theorem math japonica 24 1979 327 330 fixed point theorem to multivalued maps

a variational finite volume scheme for wasserstein gradient flows we propose a variational finite volume scheme to approximate the solutions to wasserstein gradient flows the time discretization is based on an implicit linearization of the wasserstein distance expressed thanks to benamou brenier formula whereas space discretization relies on upstream mobility two point flux approximation finite volumes our scheme is based on a first discretize then optimize approach in order to preserve the variational structure of the continuous model at the discrete level our scheme can be applied to a wide range of energies guarantees non negativity of the discrete solutions as well as decay of the energy we show that our scheme admits a unique solution whatever the convex energy involved in the continuous problem and we prove its convergence in the case of the linear fokker planck equation with positive initial density numerical illustrations show that it is first order accurate in both time and space and robust with respect to both the energy and the initial profile

some new fixed point theorems in menger pm spaces with application to volterra type integral equation abstract we establish some fixed point theorems by introducing two new classes of contractive mappings in menger pm spaces first we prove our results for an type contractive mapping and then for a generalized type contractive mapping some examples and an application to volterra type integral equation are given to support the obtained results

transformation theorems for fuzzy integrals on fuzzy sets abstract in this paper sugeno s fuzzy integrals studied in 5 8 9 are generalized some equivalent definitions of fuzzy integrals on fuzzy sets are given and several transformation theorems of such type of fuzzy integrals are proved these results reveal the relations between the fuzzy integrals on fuzzy sets and on classical sets

multi valued nonlinear contraction mappings abstract two concepts of nonlinear contractions for multi valued mappings in complete metric spaces are introduced and three fixed point theorems are proved presented theorems are generalizations of very recent fixed point theorems due to klim and wardowski d klim d wardowski fixed point theorems for set valued contractions in complete metric spaces j math anal appl 334 2007 132 139 and feng and liu y feng s liu fixed point theorems for multi valued contractive mappings and multi valued caristi type mappings j math anal appl 317 2006 103 112 as well as a fixed point theorem of mizoguchi and takahashi n mizoguchi w takahash fixed point theorems for multi valued mappings on complete metric spaces j math anal appl 141 1989 177 188 and several others an example is given to show that presented results are genuine generalizations our results are also some contribution to an open problem raised by reich s reich fixed points of contractive functions boll unione mat ital 5 1972 26 42 s reich some fixed point problems atti acad naz lincei 57 1974 194 198 s reich some problems and results in fixed point theory contemp math 21 1983 179 187

fuzzy random reliability of structures based on fuzzy random variables abstract using fuzzy random variables as basic variables the relationship between fuzzy random variables and fuzzy random events is established in this paper formulas of measures of a fuzzy random event and its cut set are presented the fuzzy random reliability of structures is defined on the basis of fuzzy measure and fuzzy integral further by using fuzzy random variables the fuzzy random failure function of structures is defined and the fuzziness between structural reliable state and failure state is also analyzed moreover the fuzzy random limit state equation of structures is built the probability calculation method of structural reliability under the reliable level is given finally the calculation procedures of structural fuzzy random reliability is proposed

fixed point theorems for multi valued contractions in complete metric spaces abstract in this paper the concept of a contraction for multi valued mappings in a metric space is introduced and the existence theorems for fixed points of such contractions in a complete metric space are proved presented results generalize and improve the recent results of y feng s liu y feng s liu fixed point theorems for multi valued contractive mappings and multi valued caristi type mappings j math anal appl 317 2006 103 112 d klim d wardowski d klim d wardowski fixed point theorems for set valued contractions in complete metric spaces j math anal appl 334 2007 132 139 and several others the method used in the proofs of our results is new and is simpler than methods used in the corresponding papers two examples are given to show that our results are genuine generalization of the results of feng and liu and klim and wardowski

fixed points for φ ψ p weakly contractive mappings in metric spaces with w distance the fixed point theorems presented in this paper generalize recent results of dutta and choudhury 3 branciari 2 banach 1 rhoades 9 khan et al 6 kada 5 and rhoades and abbas 10

common fixed point theorems for non self mappings in metric spaces of hyperbolic type in this paper the concept of a pair of non linear contraction type mappings in a metric space of hyperbolic type is introduced and the conditions guaranteeing the existence of a common fixed point for such non linear contractions are established presented results generalize and improve some of the known results an example is constructed to show that our theorems are genuine generalizations of the main theorems of assad ciric khan et al rhoades and imdad and kumar one of the possible applications of our results is also presented

fixed point theorems for multi valued contractive mappings and multi valued caristi type mappings abstract in this paper the famous banach contraction principle and caristi s fixed point theorem are generalized to the case of multi valued mappings our results are extensions of the well known nadler s fixed point theorem s b nadler jr multi valued contraction mappings pacific j math 30 1969 475 487 as well as of some caristi type theorems for multi valued operators see n mizoguchi w takahashi fixed point theorems for multivalued mappings on complete metric spaces j math anal appl 141 1989 177 188 j p aubin optima and equilibria an introduction to nonlinear analysis grad texts in math springer verlag berlin 1998 p 17 s s zhang q luo set valued caristi fixed point theorem and ekeland s variational principle appl math mech 10 2 1989 111 113 in chinese english translation appl math mech english ed 10 2 1989 119 121 etc

pseudo additive measures and integrals abstract we suggest pseudo additive measures based on a pseudo addition and discuss integrals with respect to pseudo additive measures a pseudo additive measure is a special type of fuzzy measures to define an integral a multiplication corresponding to a pseudo addition is introduced the resulting integral is an extension of the lebesgue integral in this context radon nikodym like theorems are shown

fixed point theorems for multivalued mappings on complete metric spaces on obtient une version multivaluee du theoreme de point fixe de caristi qui est equivalent au principe e variationnel du a ekeland on utilise ce resultat pour obtenir un theoreme qui deduit le theoreme de nadler et un theoreme de point fixe commun pour une application a 1 valeur et une application multivaluee

fixed point theorems for multi valued contractions with w distance some fixed point theorems for a few nonlinear multi valued contraction mappings in complete metric spaces with w distance are proved the results presented in this paper generalize the recent results due to ciric 2009 3 feng and liu 2006 4 klim and wardowski 2007 8 latif and abdou 2011 12 and liu et al 2010 14 seven examples are given to explain our results

common fixed points for maps on metric space with w distance abstract the purpose of this paper is to generalize and to unify fixed point theorems of das and naik ciric jungck and ume in terms of a w distance on complete metric space

common fixed points for four maps in cone metric spaces the existence of coincidence points and common fixed points for four mappings satisfying generalized contractive conditions without exploiting the notion of continuity of any map involved therein in a cone metric space is proved these results extend unify and generalize several well known comparable results in the existing literature

pair of non self mappings and common fixed points we study quasi contraction type non self mappings on takahashi convex metric spaces and common fixed point theorems for a pair of maps results generalizing and unifying fixed point theorems of imdad and kumar das and naik jungck ciric ume khan and pathak and ciric are established

multi valued non self mappings on convex metric spaces abstract in this paper we prove common fixed point theorems for a pair of multi valued non self mappings in metrically convex metric spaces our results generalize and extend both theorems of itoh comment math univ carolin 18 1977 247 and khan pacific j math 95 1981 337 the theorem of assad boll un math ital 4 1973 1 the theorem of rhoades comment math univ carolin 37 1996 401 and the main theorem of assad and kirk pacific j math 43 1972 535

multivalued generalized nonlinear contractive maps and fixed points abstract we introduce some notions of generalized nonlinear contractive maps and prove some fixed point results for such maps consequently several known fixed point results are either improved or generalized including the corresponding recent fixed point results of ciric l b ciric multivalued nonlinear contraction mappings nonlinear anal 71 2009 2716 2723 klim and wardowski d klim d wardowski fixed point theorems for set valued contractions in complete metric spaces j math anal appl 334 2007 132 139 feng and liu y feng s liu fixed point theorems for multivalued contractive mappings and multivalued caristi type mappings j math anal appl 317 2006 103 112 and mizoguchi and takahashi n mizoguchi w takahashi fixed point theorems for multivalued mappings on complete metric spaces j math anal appl 141 1989 177 188

on the extension of possibility measures abstract in this paper the theory of extension of possibility measures is discussed first we introduce two classes b and b of sets called the ecp system and the cp system respectively and prove that the class a d of all atoms of a class d introduced in 3 4 must be an ecp system and a cp system furthermore the extension theorem from b resp b to u b resp the generalized field or the topology generated by b of the possibility measures is proved

fixed point theorems related to ciric s contraction principle abstract in this paper we prove fixed point theorems in a complete metric space using the concept of a w distance and more general contractive mapping than quasi contractive mapping these theorems improve fixed point theorems of kannan ciric and kada suzuki and takashi

an extension of lakzian rhoades results in the structure of ordered b metric spaces via wt distance with an application abstract in this present article we establish two new kinds of nonlinear contraction mappings to obtain fixed point results in the structure of ordered b metric space via wt distance in fact our presented results are extensions of recent theorems due to lakzian rhoades 2019 appl math comput and other existing classical results of fixed point theory furthermore we provide examples to show the validity of our new investigations as an application we apply our new findings to obtain solution of a matrix equation finally we verify the accuracy of our new results numerically

fuzzy integrals on l fuzzy sets abstract the fuzzy measures and fuzzy integrals for zadeh s fuzzy sets were studied by qiao and wang 5 6 7 12 in this paper we consider the real valued fuzzy measures and fuzzy integrals for l fuzzy sets where l is a pseudocomplemented infinitely distributive complete lattice on a fuzzy algebra of l fuzzy sets the concepts of fuzzy measure and fuzzy integral are introduced some equivalent forms of fuzzy integrals on l fuzzy sets are given moreover we discuss several properties of fuzzy integrals on l fuzzy sets and prove some convergence theorems for a sequence of fuzzy integrals on l fuzzy sets

iterative construction of fixed points of nonself mappings in banach spaces the purpose of this paper is to study the iterative methods for constructing fixed points of nonself mappings in banach spaces the concept of the class of asymptotically q g weakly contractive nonself mappings is introduced and a new iterative algorithm for finding fixed points of this class of mappings is studied several strong convergence results on this algorithm are established under different conditions

non self mappings satisfying non linear contractive condition with applications abstract the concept of non self mappings satisfying a new non linear contractive type condition is introduced and coincidence and common fixed point theorems in metric spaces of hyperbolic type are proved presented theorems generalize and improve recent theorems of imdad and kumar m imdad s kumar rhoades type fixed point theorems for a pair of nonself mappings comput math appl 46 2003 919 927 and several others theorems one example is constructed to show that our theorems are genuine generalizations of the above mentioned results of imdad and kumar and several others

a fully discrete variational scheme for solving nonlinear fokker planck equations in multiple space dimensions we introduce a novel spatio temporal discretization for nonlinear fokker planck equations on the multidimensional unit cube this discretization is based on two structural properties of these equations the first is the representation as a gradient flow of an entropy functional in the l 2 wasserstein metric the second is the lagrangian nature meaning that solutions can be written as the push forward transformation of the initial density under suitable flow maps the resulting numerical scheme is entropy diminishing and mass conserving further we are able to prove consistency in the sense that if the discrete solutions are regular independently of the mesh size then they converge to a classical solution finally we present results from numerical experiments in space dimension d 2

transformation theorems of abstract integrals on fuzzy sets abstract the concept of abstract integrals on fuzzy sets is introduced and some elementary properties for such type of integrals are given this paper also proves some transformation theorems for abstract integrals on fuzzy sets and presents some convergence theorems of a sequence of abstract integrals