共查询到20条相似文献,搜索用时 312 毫秒
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The strong normalization theorem is uniformly proved for typed λ-calculi for a wide range of substructural logics with or
without strong negation.
We would like to thank the referees for their valuable comments and suggestions. This research was supported by the Alexander
von Humboldt Foundation. The second author is grateful to
the Foundation for providing excellent working conditions and generous support of this research.
This work was also supported by the Japanese Ministry of Education, Culture, Sports, Science
and Technology, Grant-in-Aid for Young Scientists (B) 20700015, 2008. 相似文献
4.
We study discrete curvatures computed from nets of curvature lines on a given smooth surface and prove their uniform convergence
to smooth principal curvatures. We provide explicit error bounds, with constants depending only on properties of the smooth
limit surface and the shape regularity of the discrete net. 相似文献
5.
With a plane curve singularity one associates a multi-index filtration on the ring of germs of functions of two variables
defined by the orders of a function on irreducible components of the curve. The Poincaré series of this filtration turns out
to coincide with the Alexander polynomial of the curve germ. For a finite set of divisorial valuations on the ring corresponding
to some components of the exceptional divisor of a modification of the plane, in a previous paper there was obtained a formula
for the Poincaré series of the corresponding multi-index filtration similar to the one associated with plane germs. Here we
show that the Poincaré series of a set of divisorial valuations on the ring of germs of functions of two variables defines
“the topology of the set of the divisors” in the sense that it defines the minimal resolution of this set up to combinatorial
equivalence. For the plane curve singularity case, we also give a somewhat simpler proof of the statement by Yamamoto which
shows that the Alexander polynomial is equivalent to the embedded topology. 相似文献
6.
William Y. C. Chen Larry X. W. Wang Arthur L. B. Yang 《Journal of Algebraic Combinatorics》2010,32(3):303-338
We prove two recent conjectures of Liu and Wang by establishing the strong q-log-convexity of the Narayana polynomials, and showing that the Narayana transformation preserves log-convexity. We begin with a formula of Brändén expressing the q-Narayana numbers as a specialization of Schur functions and, by deriving several symmetric function identities, we obtain the necessary Schur-positivity results. In addition, we prove the strong q-log-concavity of the q-Narayana numbers. The q-log-concavity of the q-Narayana numbers N q (n,k) for fixed k is a special case of a conjecture of McNamara and Sagan on the infinite q-log-concavity of the Gaussian coefficients. 相似文献
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Theodore Tachim Medjo 《Applied Mathematics and Optimization》2010,62(1):1-26
We consider a class of stochastic impulse control problems of general stochastic processes i.e. not necessarily Markovian.
Under fairly general conditions we establish existence of an optimal impulse control. We also prove existence of combined
optimal stochastic and impulse control of a fairly general class of diffusions with random coefficients. Unlike, in the Markovian
framework, we cannot apply quasi-variational inequalities techniques. We rather derive the main results using techniques involving
reflected BSDEs and the Snell envelope. 相似文献
9.
Daniel M. Oberlin 《Journal of Geometric Analysis》2010,20(2):422-438
We study lower bounds for the Minkowski and Hausdorff dimensions of the algebraic sum E+K of two sets E,K⊂ℝ
d
. 相似文献
10.
Given a set of vectors F={f
1,…,f
m
} in a Hilbert space H\mathcal {H}, and given a family C\mathcal {C} of closed subspaces of H\mathcal {H}, the subspace clustering problem consists in finding a union of subspaces in C\mathcal {C} that best approximates (is nearest to) the data F. This problem has applications to and connections with many areas of mathematics, computer science and engineering, such
as Generalized Principal Component Analysis (GPCA), learning theory, compressed sensing, and sampling with finite rate of
innovation. In this paper, we characterize families of subspaces C\mathcal {C} for which such a best approximation exists. In finite dimensions the characterization is in terms of the convex hull of an
augmented set C+\mathcal {C}^{+}. In infinite dimensions, however, the characterization is in terms of a new but related notion; that of contact half-spaces.
As an application, the existence of best approximations from π(G)-invariant families C\mathcal {C} of unitary representations of Abelian groups is derived. 相似文献
11.
The M/G/K queueing system is one of the oldest models for multiserver systems and has been the topic of performance papers for almost
half a century. However, even now, only coarse approximations exist for its mean waiting time. All the closed-form (nonnumerical)
approximations in the literature are based on (at most) the first two moments of the job size distribution. In this paper
we prove that no approximation based on only the first two moments can be accurate for all job size distributions, and we
provide a lower bound on the inapproximability ratio, which we refer to as “the gap.” This is the first such result in the
literature to address “the gap.” The proof technique behind this result is novel as well and combines mean value analysis,
sample path techniques, scheduling, regenerative arguments, and asymptotic estimates. Finally, our work provides insight into
the effect of higher moments of the job size distribution on the mean waiting time. 相似文献
12.
Andrzej Derdzinski 《Journal of Geometric Analysis》2009,19(2):301-357
The local structure of the manifolds named in the title is described. Although curvature homogeneous, they are not, in general,
locally homogeneous. Not all of them are Ricci-flat, which answers an existence question about type III Jordan-Osserman metrics,
raised by Díaz-Ramos, García-Río and Vázquez-Lorenzo (J. Geom. Anal. 16, 39–52, 2006).
Work begun during the author’s visit to the University of Santiago de Compostela, supported by Grant MTM2006-01432 (Spain). 相似文献
13.
Let M be a generic CR manifold in
\BbbCm+d\Bbb{C}^{m+d} of codimension d, locally given as the common zero set of real-valued functions r
1,…,r
d
. Given an integer δ=1,…,d, we find a necessary and sufficient condition for M to contain a real submanifold of codimension δ with the same CR structure. We also find a necessary and sufficient condition and several sufficient conditions for M to admit a complex submanifold of complex dimension n, for any n=1,…,m. We use the method of prolongation of an exterior differential system. The conditions are systems of partial differential
equations on r
1,…,r
d
of third order. 相似文献
14.
John R. Akeroyd 《Arkiv f?r Matematik》2011,49(1):1-16
It is shown that for any t, 0<t<∞, there is a Jordan arc Γ with endpoints 0 and 1 such that
G\{1} í \mathbbD:={z:|z| < 1}\Gamma\setminus\{1\}\subseteq\mathbb{D}:=\{z:|z|<1\}
and with the property that the analytic polynomials are dense in the Bergman space
\mathbbAt(\mathbbD\G)\mathbb{A}^{t}(\mathbb{D}\setminus\Gamma)
. It is also shown that one can go further in the Hardy space setting and find such a Γ that is in fact the graph of a continuous
real-valued function on [0,1], where the polynomials are dense in
Ht(\mathbbD\G)H^{t}(\mathbb{D}\setminus\Gamma)
; improving upon a result in an earlier paper. 相似文献
15.
Donald St. P. Richards 《The Ramanujan Journal》2010,23(1-3):397-407
We establish a positivity property for the difference of products of certain Schur functions, s λ (x), where λ varies over a fundamental Weyl chamber in ? n and x belongs to the positive orthant in ? n . Further, we generalize that result to the difference of certain products of arbitrary numbers of Schur functions. We also derive a log-convexity property of the generalized hypergeometric functions of two Hermitian matrix arguments, and we show how that result may be extended to derive higher-order log-convexity properties. 相似文献
16.
In the paper we obtain an explicit formula for the intrinsic diameter of the surface of a rectangular parallelepiped in 3-dimensional
Euclidean space. As a consequence, we prove that an parallelepiped with relation
for its edge lengths has maximal surface area among all rectangular parallelepipeds with given intrinsic diameter. 相似文献
17.
In this paper we study the possible orders of a non-abelian representation group of a slim dense near hexagon. We prove that
if the representation group R of a slim dense near hexagon S is non-abelian, then R is a 2-group of exponent 4 and |R|=2
β
, 1+NPdim(S)≤β≤1+dimV(S), where NPdim(S) is the near polygon embedding dimension of S and dimV(S) is the dimension of the universal representation module V(S) of S. Further, if β=1+NPdim(S), then R is necessarily an extraspecial 2-group. In that case, we determine the type of the extraspecial 2-group in each case. We
also deduce that the universal representation group of S is a central product of an extraspecial 2-group and an abelian 2-group of exponent at most 4.
This work was partially done when B.K. Sahoo was a Research Fellow at the Indian Statistical Institute, Bangalore Center with
NBHM fellowship, DAE Grant 39/3/2000-R&D-II, Govt. of India. 相似文献
18.
A general framework for a class of overrelaxed proximal point algorithms based on the notion of relative A-maximal monotonicity is introduced; then, the convergence analysis for solving a general class of nonlinear variational inclusion
problems is explored. The framework developed in this communication is quite suitable, unlike other existing notions of generalized
maximal monotonicity, including A-maximal (m)-relaxed monotonicity in literature, to generalize first-order nonlinear evolution equations/evolution inclusions based on
the generalized nonlinear Yosida approximations in Hilbert spaces as well as in Banach spaces. 相似文献
19.
We study the effect of a magnetic field on the behaviour of a slender conducting elastic structure, motivated by stability
problems of electrodynamic space tethers. Both static (buckling) and dynamic (whirling) instability are considered and we
also compute post-buckling configurations. The equations used are the geometrically exact Kirchhoff equations. Magnetic buckling
of a welded rod is found to be described by a surprisingly degenerate bifurcation, which is unfolded when both transverse
anisotropy of the rod and angular velocity are considered. By solving the linearised equations about the (quasi-) stationary
solutions, we find various secondary instabilities. Our results are relevant for current designs of electrodynamic space tethers
and potentially for future applications in nano- and molecular wires. 相似文献
20.
Takahiro Tsushima 《Mathematische Zeitschrift》2011,269(1-2):411-447
Abbes, Kato and Saito generalize the Grothendieck-Ogg-Shafarevich formula to an arbitrary dimension (Kato and Saito in Ann. Math. 168:33–96, 2008; Abbes and Saito in Invent. Math. 168:567–612, 2007). In this paper, assuming the strong resolution of singularities, we prove a localized version of a formula proved using the characteristic class of an ?-adic sheaf by Abbes and Saito (Invent Math 168:567–612, 2007). We prove a localized version of the Lefschetz-Verdier trace formula proved in Grothendieck (Formule de Lefschetz, exposé III, SGA 5, Lect. Notes Math., vol 589, pp 372–406, Exp. X, Springer, Berlin, 1977 [Théorème 4.4]). As an application, we prove a conductor formula in an arbitrary dimension in the equal characteristic case. 相似文献