@unpublished{CattiauxDaiPraPoelly2007, author = {Cattiaux, Patrick and Dai Pra, Paolo and Poelly, Sylvie}, title = {A constructive approach to a class of ergodic HJB equations with nonsmooth cost}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-49430}, year = {2007}, abstract = {We consider a class of ergodic Hamilton-Jacobi-Bellman (HJB) equations, related to large time asymptotics of non-smooth multiplicative functional of difusion processes. Under suitable ergodicity assumptions on the underlying difusion, we show existence of these asymptotics, and that they solve the related HJB equation in the viscosity sense.}, language = {en} } @unpublished{CattiauxFradonKuliketal.2013, author = {Cattiaux, Patrick and Fradon, Myriam and Kulik, Alexei Michajlovič and Roelly, Sylvie}, title = {Long time behavior of stochastic hard ball systems}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-68388}, year = {2013}, abstract = {We study the long time behavior of a system of two or three Brownian hard balls living in the Euclidean space of dimension at least two, submitted to a mutual attraction and to elastic collisions.}, language = {en} } @unpublished{ChampagnatRoelly2007, author = {Champagnat, Nicolas and Roelly, Sylvie}, title = {Limit theorems for conditioned multitype Dawson-Watanabe processes}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-49426}, year = {2007}, abstract = {A multitype Dawson-Watanabe process is conditioned, in subcritical and critical cases, on non-extinction in the remote future. On every nite time interval, its distribution law is absolutely continuous with respect to the law of the unconditioned process. A martingale problem characterization is also given. The explicit form of the Laplace functional of the conditioned process is used to obtain several results on the long time behaviour of the mass of the conditioned and unconditioned processes. The general case is considered first, where the mutation matrix which modelizes the interaction between the types, is irreducible. Several two-type models with decomposable mutation matrices are also analysed.}, language = {en} } @unpublished{ChenHidetoshi1998, author = {Chen, Hua and Hidetoshi, Tahara}, title = {On the holomorphic solution of non-linear totally characteristic equations}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-25333}, year = {1998}, abstract = {The paper deals with a non-linear singular partial differential equation: (E) t∂/∂t = F(t, x, u, ∂u/∂x) in the holomorphic category. When (E) is of Fuchsian type, the existence of the unique holomorphic solution was established by G{\´e}rard-Tahara [2]. In this paper, under the assumption that (E) is of totally characteristic type, the authors give a sufficient condition for (E) to have a unique holomorphic solution. The result is extended to higher order case.}, language = {en} } @unpublished{ChenLiLiu2008, author = {Chen, Hua and Li, Jun-Feng and Liu, Wei-An}, title = {Behavior of the solution to a chemotaxis model with reproduction term}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-30304}, year = {2008}, abstract = {Contents: 1 Introduction 2 Global existence and blow-up or quenching of the solution 3 Detailed asymptotical behavior of the solution}, language = {en} } @unpublished{ChenLi2007, author = {Chen, Hua and Li, Ke}, title = {The existence and regularity of multiple solutions for a class of infinitely degenerate elliptic equations}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-30247}, year = {2007}, abstract = {Let X = (X1,.....,Xm) be an infinitely degenerate system of vector fields, we study the existence and regularity of multiple solutions of Dirichelt problem for a class of semi-linear infinitely degenerate elliptic operators associated with the sum of square operator Δx = ∑m(j=1) Xj* Xj.}, language = {en} } @unpublished{ChenLiXu2007, author = {Chen, Hua and Li, Wei-Xi and Xu, Chao-Jiang}, title = {Gevrey hypoellipticity for linear and non-linear Fokker-Planck equations}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-30283}, year = {2007}, abstract = {This paper studies the Gevrey regularity of weak solutions of a class of linear and semilinear Fokker-Planck equations.}, language = {en} } @unpublished{ChenLua1998, author = {Chen, Hua and Lua, Zhuangehu}, title = {On the holomorphic solution of non-linear totally characteristic equations with several space variables}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-25189}, year = {1998}, abstract = {In this paper we study a class of non-linear singular partial differential equation in complex domain Csub(t) x C n sub(x). Under certain assumptions, we prove the existence and uniqueness of holomorphic solution near origin of Csub(t) x C n sub(x).}, language = {en} } @unpublished{ChenWu2006, author = {Chen, Hua and Wu, Shaohua}, title = {On existence of solutions for some hyperbolic-parabolic type chemotaxis systems}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-30082}, year = {2006}, abstract = {In this paper, we discuss the local and global existence of week solutions for some hyperbolic-parabolic systems modelling chemotaxis.}, language = {en} } @unpublished{ChenYu2001, author = {Chen, Hua and Yu, Chun}, title = {Asymptotic behaviour of the trace for Schr{\"o}dinger operator on fractal drums}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-26157}, year = {2001}, language = {en} } @unpublished{CoriascoPanarese2000, author = {Coriasco, Sandro and Panarese, Paolo}, title = {Fourier integral operators defined by classical symbols with exit behaviour}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-25896}, year = {2000}, abstract = {We continue the investigation of the calculus of Fourier Integral Operators (FIOs) in the class of symbols with exit behaviour (SG symbols). Here we analyse what happens when one restricts the choice of amplitude and phase functions to the subclass of the classical SG symbols. It turns out that the main composition theorem, obtained in the environment of general SG classes, has a "classical" counterpart. As an application, we study the Cauchy problem for classical hyperbolic operators of order (1, 1); for such operators we refine the known results about the analogous problem for general SG hyperbolic operators. The material contained here will be used in a forthcoming paper to obtain a Weyl formula for a class of operators defined on manifolds with cylindrical ends, improving the results obtained in [9].}, language = {en} } @unpublished{CoriascoSchroheSeiler2001, author = {Coriasco, Sandro and Schrohe, Elmar and Seiler, J{\"o}rg}, title = {Bounded imaginary powers of differential operators on manifolds with conical singularities}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-25962}, year = {2001}, abstract = {We study the minimal and maximal closed extension of a differential operator A on a manifold B with conical singularities, when A acts as an unbounded operator on weighted Lp-spaces over B,1 < p < ∞. Under suitable ellipticity assumptions we can define a family of complex powers A up(z), z ∈ C. We also obtain sufficient information on the resolvent of A to show the boundedness of the pure imaginary powers. Examples concern unique solvability and maximal regularity of the solution of the Cauchy problem u' - Δu = f, u(0) = 0, for the Laplacian on conical manifolds.}, language = {en} } @unpublished{CoriascoSchulze2002, author = {Coriasco, Sandro and Schulze, Bert-Wolfgang}, title = {Edge problems on configurations with model cones of different dimensions}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-26438}, year = {2002}, abstract = {Elliptic equations on configurations W = W1 ∪ ... ∪ Wn with edge Y and components Wj of different dimension can be treated in the frame of pseudo-differential analysis on manifolds with geometric singularities, here, edges. Starting from edge-degenerate operators on Wj, j = 1, ..., N, we construct an algebra with extra "transmission" conditions on Y that satisfy an analogue of the Shapiro-Lopatinskij condition. Ellipticity refers to a two-component symbolic hierarchy with an interior and an edge part; the latter one is operator-valued, operating on the union of different dimensional model cones. We construct parametrices within our calculus, where exchange of information between the various components is encoded in Green and Mellin operators that are smoothing on W\Y. Moreover, we obtain regularity of solutions in weighted edge spaces with asymptotics.}, language = {en} } @unpublished{Davis2002, author = {Davis, Simon}, title = {On the absence of large-order divergences in superstring theory}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-26452}, year = {2002}, abstract = {The genus-dependence of multi-loop superstring ams is estimated at large orders in perturbation theory using the super-Schottky group parameterization of supermoduli space. Restriction of the integration region to a subset of supermoduli space and a single fundamental domain of the super-modular group suggests an exponential dependence on the genus. Upper bounds for these estimates are obtained for arbitrary N-point superstring scattering amplitudes and are shown to be consistent with exact results obtained for special type II string amplitudes for orbifold or Calabi-Yau compactifications. The genus-dependence is then obtained by considering the effect of the remaining contribution to the superstring amplitudes after the coefficients of the formally divergent parts of the integrals vanish as a result of a sum over spin structures. The introduction of supersymmetry therefore leads to the elimination of large-order divergences in string pertubation theory, a result which is based only on the supersymmetric generalization of the polyakov measure and not the gauge group of the string model.}, language = {en} } @unpublished{Davis2002, author = {Davis, Simon}, title = {Connections and generalized gauge transformations}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-26468}, year = {2002}, abstract = {The derivation of the standard model from a higher-dimensional action suggests a further study of the fibre bundle formulation of gauge theories to determine the variations in the choice of structure group that are allowed in this geometrical setting. The action of transformations on the projection of fibres to their submanifolds are characteristic of theories with fewer gauge vector bosons, and specific examples are given, which may have phenomenological relevance. The spinor space for the three generations of fermions in the standard model is described algebraically.}, language = {en} } @unpublished{Davis2002, author = {Davis, Simon}, title = {On the existence of a non-zero lower bound for the number of Goldbach partitions of an even integer}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-26474}, year = {2002}, abstract = {The Goldbach partitions of an even number greater than 2, given by the sums of two prime addends, form the non-empty set for all integers 2n with 2 ≤ n ≤ 2 × 1014. It will be shown how to determine by the method of induction the existence of a non-zero lower bound for the number of Goldbach partitions of all even integers greater than or equal to 4. The proof depends on contour arguments for complex functions in the unit disk.}, language = {en} } @unpublished{Davis2003, author = {Davis, Simon}, title = {The quantum cosmological wavefunction at very early times for a quadratic gravity theory}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-26520}, year = {2003}, abstract = {The quantum cosmological wavefunction for a quadratic gravity theory derived from the heterotic string effective action is obtained near the inflationary epoch and during the initial Planck era. Neglecting derivatives with respect to the scalar field, the wavefunction would satisfy a third-order differential equation near the inflationary epoch which has a solution that is singular in the scale factor limit a(t) → 0. When scalar field derivatives are included, a sixth-order differential equation is obtained for the wavefunction and the solution by Mellin transform is regular in the a → 0 limit. It follows that inclusion of the scalar field in the quadratic gravity action is necessary for consistency of the quantum cosmology of the theory at very early times.}, language = {en} } @unpublished{DeDonnoSchulze2003, author = {De Donno, G. and Schulze, Bert-Wolfgang}, title = {Meromorphic symbolic structures for boundary value problems on manifolds with edges}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-26570}, year = {2003}, abstract = {We investigate the ideal of Green and Mellin operators with asymtotics for a manifold with edge-corner singularities and boundary which belongs to the structure of parametrices of elliptic boundary value problems on a configuration with corners whose base manifolds have edges.}, language = {en} } @unpublished{DeXingHui2003, author = {De-Xing, Kong and Hui, Yao}, title = {Global exact boundary controllability of a class of quasilinear hyperbolic systems of conservation laws II}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-26565}, year = {2003}, abstract = {In this paper, by a new constructive method, the authors reprove the global exact boundary controllability of a class of quasilinear hyperbolic systems of conservation laws with linearly degenerate fields. It is shown that the system with nonlinear boundary conditions is globally exactly boundary controllable in the class of piecewise C¹ functions. In particular, the authors give the optimal control time of the system. Finally, a new application is also given.}, language = {en} } @unpublished{DenkKrainer2006, author = {Denk, Robert and Krainer, Thomas}, title = {R-Boundedness, pseudodifferential operators, and maximal regularity for some classes of partial differential operators}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-30147}, year = {2006}, abstract = {It is shown that an elliptic scattering operator A on a compact manifold with boundary with operator valued coefficients in the morphisms of a bundle of Banach spaces of class (HT ) and Pisier's property (α) has maximal regularity (up to a spectral shift), provided that the spectrum of the principal symbol of A on the scattering cotangent bundle avoids the right half-plane. This is accomplished by representing the resolvent in terms of pseudodifferential operators with R-bounded symbols, yielding by an iteration argument the R-boundedness of λ(A - λ)-1 in R(λ)≥ τ for some τ ∈ IR. To this end, elements of a symbolic and operator calculus of pseudodifferential operators with R-bounded symbols are introduced. The significance of this method for proving maximal regularity results for partial differential operators is underscored by considering also a more elementary situation of anisotropic elliptic operators on Rd with operator valued coefficients.}, language = {en} }