extended cesaro operators on bergman spaces we define an extended cesaro operator tg with holomorphic symbol g in the unit ball b of cn for a large class of weights w we characterize those g for which tg is bounded or compact from bergman space lpa w b to lqa w b 0 p q in addition we obtain some results about equivalent norms the norm of point evaluation functionals and the interpolation sequences on lpa w b

asymptotic form of the approach to equilibrium in reversible recombination reactions the reversible reactions and are investigated from the exact langevin equations describing our model we set up a systematic approximation scheme to compute the approach of the density of c particles to its equilibrium value we show that for a sufficiently long time t this approach takes the form of a power law for any dimension d the amplitude a is also computed exactly but is expected to be model dependent for uncorrelated initial conditions the c density turns out to be a monotonic time function the cases of correlated initial conditions and unequal diffusion constants are investigated as well in the former correlations may break the monotonicity of the density or in some special cases they may change the long time behaviour for the latter the power law remains valid only the amplitude changes even in the extreme case of immobile c particles we also consider the case of segregated initial condition for which a reaction front is observed and confirm that its width is governed by mean field exponent in any dimension

on an integral type operator from logarithmic bloch type and mixed norm spaces to bloch type spaces abstract this paper studies the boundedness and compactness of the following integral type operator recently introduced by this author p g f z 0 1 f t z g t z d t t z b where is a holomorphic self map of the unit ball b in c n and g is a holomorphic function on b such that g 0 0 from logarithmic bloch type and mixed norm spaces to bloch type spaces

on a product type operator from bloch spaces to weighted type spaces on the unit ball we characterize the boundedness and compactness of a product of radial derivative composition and multiplication operators from bloch spaces to weighted type spaces on the unit ball

on a product type operator from weighted bergman orlicz space to some weighted type spaces let d z c z 1 be the open unit disk an analytic self map of d and an analytic function on d let d be the differentiation operator and w the weighted composition operator the boundedness and compactness of the product type operator dw from the weighted bergman orlicz space to the bers type space weighted bloch space and weighted zygmund space on d are characterized

on second moment properties of median filtered sequences of independent data in this paper we present the derivation of the bivariate distribution function for median filtered sequences of independent arbitrary second order random variables this result is then used to qualitatively analyze second moment properties of median filtered data the results hint towards a low pass characteristic of the median filters and a low dependency of the output spectrum on input alphabet size and distribution

on blog to qlogp pullbacks abstract we characterize the boundedness and the compactness of composition operators acting on the weighted bloch space b log generalizing previous results and answering to a question of r yoneda

generalized product type operators from weighted bergman orlicz spaces to bloch orlicz spaces let d be the open unit disk in the complex plane an analytic self map of d and an analytic function on d let dn be the nth differentiation operator and w the weighted composition operator in this paper the boundedness and compactness of the generalized product type operators dnw and w dn from weighted bergman orlicz spaces to bloch orlicz spaces are characterized

statistical analysis of morphological openings statistical analysis of morphological openings is carried out to study noise suppression and edge preserving properties of binary and gray scale structuring elements based on the fact that basis functions are a general representation of any morphological mapping that is translation invariant and increasing it is shown that a statistical analysis using this representation is feasible and more general than the threshold decomposition approach

variational and potential formulation for stochastic partial differential equations recently there has been interest in finding a potential formulation for stochastic partial differential equations spdes the rationale behind this idea lies in obtaining all the dynamical information of the system under study from one single expression in this letter we formally provide a general lagrangian formalism for spdes using the hojman et al method we show that it is possible to write the corresponding effective potential starting from an s equivalent lagrangian and that this potential is able to reproduce all the dynamics of the system once a special differential operator has been applied this procedure can be used to study the complete time evolution and spatial inhomogeneities of the system under consideration and is also suitable for the statistical mechanics description of the problem

extended cesaro operators between bloch type spaces in the unit ball of cn abstract in this paper we characterize those holomorphic symbols in the unit ball of c n for which the induced extended cesaro operator t b b respectively b 0 b 0 is bounded or compact where and are normal functions on 0 1 in addition we obtain some properties of those spaces b and b 0

composition operators from bloch type spaces into qk type spaces supposeis an analytic map of the unit disk d into itself x is a banach space of analytic functions on d define the composition operator c cf f for all f x in this paper the boundedness and compactness of the composition operators from bloch spaces into qk p q and qk 0 p q spaces are discussed where 0 keywords composition operator analytic function bspace k carleson measure compact k carleson measure

compact composition operators on the bloch space necessary and sufficient conditions are given for a composition operator cof f o q to be compact on the bloch space w and on the little bloch space o weakly compact composition operators on o are shown to be compact if q e o is a conformal mapping of the unit disk d into itself whose image q d approaches the unit circle t only in a finite number of nontangential cusps then co is compact on 7o on the other hand if there is a point of t n q d at which q d does not have a cusp then co is not compact

products of volterra type operator and composition operator from h and bloch spaces to zygmund spaces the boundedness and compactness of the products of volterra type operators and composition operators from the space of bounded analytic functions and the bloch space to the zygmund space are discussed in this paper

an efficient calculation of the moments of matched and mismatched hidden markov models streit 1990 analysed the classification of an unknown hidden markov model hmm using a set of prescribed hmms he proposed a suboptimal test statistic that can be approximated by certain moments for this classification in the present paper the algorithm given by streit to derive these moments is reformulated in a matrix algebra setting that gives a better insight into the algorithm also an asymptotic analysis of the algorithm is derived using the reformulation

cesaro operators on hardy spaces in the unit ball this article establishes the boundedness of the generalized cesaro operator on holomorphic hardy spaces in the unit ball the approach consists in writing the generalized cesaro operator as a composition of certain integral operators

products of integral type operators and composition operators between bloch type spaces a complete picture on the boundedness and compactness of the products of integral type operators and composition operators between bloch type spaces of holomorphic functions on the unit disk is given in this paper

generalized composition operators on zygmund spaces and bloch type spaces the boundedness and compactness of the generalized composition operator on zygmund spaces and bloch type spaces are investigated in this paper

the moments of matched and mismatched hidden markov models an algorithm for computing the moments of matched and mismatched hidden markov models hmms from their defining parameters is presented the algorithm is an extension of the usual forward backward linear recursion the algorithm computes the joint moments of the posterior likelihood functions i e the scores by a multilinear recursion involving the joint moments of the random variables associated with the hidden states of the markov chain examples comparing the first two theoretical moments to simulation results are presented they are of independent interest because they indicate that the distribution of the posterior likelihood function scores for mismatched models are asymptotically log normal in important special cases and therefore are characterized asymptotically by the first two moments alone one example shows that classification using a suboptimal statistic reliably distinguishes between sufficiently long quasi stationary signals with a reasonable amount of computational effort

on an integral type operator from iterated logarithmic bloch spaces into bloch type spaces let h b denote the space of all holomorphic functions on the open unit ball b of c n let f f 1 f n be a holomorphic self map of b and email protected h b such that g 0 0 in this paper we study the boundedness and compactness of the following integral type operator recently introduced by xiangling zhu and the second authori f gf z email protected 0 1rf f tz g tz dtt email protected b from the iterated logarithmic bloch spaces into the bloch type spaces for the case when f z z we also obtain a sufficient and necessary condition for the boundedness of this operator from the iterated logarithmic bloch space into the little bloch type space

a new type of kinetic critical phenomenon the authors study a new critical phenomenon in an non thermal one dimensional lattice model it is characterised by the transition from stability to instability of kinks between ordered states below the critical point the kinks are stable and move by annihilating random walks above the critical point they are unstable against creation of kink antikink pairs the spontaneous production of pairs is assumed to be absent at the critical point p pcr the density of kinks decreases like n approximately talpha with alpha 0 27 or 0 08 above the critical point the density of kinks in the stationary state is approximately p pcr beta with beta 0 06 or 0 2 possible extensions to two or more dimensions and possible applications are discussed

extended cesaro operators between different hardy spaces abstract let h p denote the hardy space of holomorphic functions on the unit ball b this note gives some sufficient and necessary conditions for the boundedness and compactness of the following extended cesaro operators t g f z 0 1 f tz r g tz dt t and l g f z 0 1 r f tz g tz dt t where z b and g is a fixed holomorphic map on b acting from the space h p into the space h q for the case p q our results extend and simplify some one dimensional results

the baker campbell hausdorff formula and nested commutator identities the coefficients of the baker campbell hausdorff expansion are calculated by using various methods comparison of the results yields several remarkable identities satisfied by multiple commutators which in turn allow us to greatly simplify the form of the expansion up to order eight

effective action for stochastic partial differential equations stochastic partial differential equations spdes are the basic tool for modeling systems where noise is important spdes are used for models of turbulence pattern formation and the structural development of the universe itself it is reasonably well known that certain spdes can be manipulated to be equivalent to nonquantum field theories that nevertheless exhibit deep and important relationships with quantum field theory in this paper we systematically extend these ideas we set up a functional integral formalism and demonstrate how to extract all the one loop physics for an arbitrary spde subject to arbitrary gaussian noise it is extremely important to realize that gaussian noise does not imply that the field variables undergo gaussian fluctuations and that these nonquantum field theories are fully interacting the limitation to one loop is not as serious as might be supposed experience with quantum field theories qfts has taught us that one loop physics is often quite adequate to give a good description of the salient issues the limitation to one loop does however offer marked technical advantages because at one loop almost any field theory can be rendered finite using zeta function technology we can sidestep the complications inherent in the martin siggia rose formalism the spde analog of the becchi rouet stora tyutin formalism used in qft and instead focus attention on a minimalist approach that uses only the physical fields this direct approach is the spde analog of canonical quantization using physical fields after setting up the general formalism for the characteristic functional partition function we show how to define the effective action to all loops and then focus on the one loop effective action and its specialization to constant fields the effective potential the physical interpretation of the effective action and effective potential for spdes is addressed and we show that key features carry over from qft to the case of spdes an important result is that the amplitude of the two point function governing the noise acts as the loop counting parameter and is the analog of planck s constant in this spde context we derive a general expression for the one loop effective potential of an arbitrary spde subject to translation invariant gaussian noise and compare this with the one loop potential for qft

goldberg s theorem and the baker campbell hausdorff formula abstract goldberg s theorem duke math j 23 1956 13 is applied to expressing the logarithm of exponential product in terms of free lie elements using hyperoperators namely inner derivations a symmetric property of the expansion coefficients in the formal power series is also discussed

on some integral type operators between a general space and bloch type spaces abstract the boundedness and compactness of the next integral operators p g f z 0 1 f tz g tz dt t and l g f z 0 1 r f tz g tz dt t between f p q s spaces and bloch type spaces on the unit ball of c n are studied among other results we solve some open problems and considerably extend results in the paper li and stevic compactness of riemann stieltjes operators between f p q s and bloch spaces publ math debrecen 72 1 2 2008 111 128

characterizations of α bloch spaces on the unit ball abstract we obtain a characterization of the bloch space for any 0 in the unit ball of c n in terms of f z f w z w moreover a new characterization for the bloch space is given

on the iterated logarithmic bloch space on the unit ball abstract we introduce a new space of analytic functions on the unit ball the so called iterated logarithmic bloch space b log k and study some of its properties among other features we study the boundedness and compactness of weighted composition operators on the unit disk as well as of a recently introduced integral type operator on the unit ball with i domain the iterated logarithmic bloch space b log k or the little iterated logarithmic bloch space b log k 0 and ii range the bloch type space b or the little bloch type space b 0 or the weighted space h or the little weighted space h 0

on a new operator from the logarithmic bloch space to the bloch type space on the unit ball abstract we study the boundedness and compactness of a recently introduced operator denoted by p g which is a kind of the product of composition and integral operators on the unit ball b c n from the logarithmic bloch space b log and the little logarithmic bloch space b log 0 to the bloch type space b or the little bloch type space b 0

weighted composition operators between weighted bergman spaces and hardy spaces on the unit ball of cn abstract in this paper we study the weighted composition operators w f f between weighted bergman spaces and hardy spaces on the unit ball of c n we characterize the boundedness and the compactness of the weighted composition operators w a p a q 0 q p 1 and w h p b h q b 0 q p

heat kernel regularization of the effective action for stochastic reaction diffusion equations the presence of fluctuations and nonlinear interactions can lead to scale dependence in the parameters appearing in stochastic differential equations stochastic dynamics can be formulated in terms of functional integrals in this paper we apply the heat kernel method to study the short distance renormalizability of a stochastic polynomial reaction diffusion equation with real additive noise we calculate the one loop effective action and its ultraviolet scale dependent divergences we show that for white noise a polynomial reaction diffusion equation is one loop finite in d 0 and d 1 and is one loop renormalizable in d 2 and d 3 space dimensions we obtain the one loop renormalization group equations and find they run with scale only in d 2

products of multiplication composition and differentiation operators on weighted bergman spaces abstract let be a holomorphic function on the open unit disk d and a holomorphic self map of d let c m and d denote the composition multiplication and differentiation operator respectively we consider linear operators induced by products of these operators on weighted bergman spaces on d the boundedness is established by using carleson type measures