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151.
Martin Henk 《Monatshefte für Mathematik》1990,110(3-4):279-282
The second theorem of Minkowski establishes a relation between the successive minima and the volume of a 0-symmetric convex body. Based on this theorem we will prove a series of inequalities connecting the product of certain successive minima with certain intrinsic volumes. 相似文献
152.
153.
In this paper we consider an open queueing network having multiple classes, priorities, and general service time distributions.
In the case where there is a single bottleneck station we conjecture that normalized queue length and sojourn time processes
converge, in the heavy traffic limit, to one-dimensional reflected Brownian motion, and present expressions for its drift
and variance. The conjecture is motivated by known heavy traffic limit theorems for some special cases of the general model,
and some conjectured “Heavy Traffic Principles” derived from them.
Using the known stationary distribution of one-dimensional reflected Brownian motion, we present expressions for the heavy
traffic limit of stationary queue length and sojourn time distributions and moments. For systems with Markov routing we are
able to explicitly calculate the limits. 相似文献
154.
Comparisons are made between the expected gain of a prophet (an observer with complete foresight) and the maximal expected gain of a gambler (using only non-anticipating stopping times) observing a sequence of independent, uniformly bounded random variables where a non-negative fixed cost is charged for each observation. Sharp universal bounds are obtained under various restrictions on the cost and the length of the sequence. For example, it is shown for X1, X2, … independent, [0, 1]-valued random variables that for all c ≥ 0 and all n ≥ 1 that E(max1 ≤ j ≤ n(Xj − jc)) − supt Tn E(Xt − tc) ≤ 1/e, where Tn is the collection of all stopping times t which are less than or equal to n almost surely. 相似文献
155.
A new construction of combings is used to distinguish
between several previously indistinguishable
classes of groups associated to the theory of automatic groups
and non-positive curvature in group theory.
We construct synchronously bounded combings for a class
of groups that are neither bicombable nor automatic.
The linguistic complexity of these combings is
analysed: in many cases the language of words
in the combing is an indexed language. 相似文献
156.
Keye Martin 《Applied Categorical Structures》2003,11(1):27-40
We introduce the triangle inequality for measurement. This is a property that when satisfied by a measurement enables one to construct a metric on the set of elements with measure zero that yields the relative Scott topology. The naturality of this construction permits a categorical solution to the model problem in domain theory for locally compact metric spaces. The first time such a solution has been achieved. 相似文献
157.
When a Fock-adapted Feller cocycle on a C*-algebra is regular,completely positive and contractive, it possesses a stochasticgenerator that is necessarily completely bounded. Necessaryand sufficient conditions are given, in the form of a sequenceof identities, for a completely bounded map to generate a weaklymultiplicative cocycle. These are derived from a product formulafor iterated quantum stochastic integrals. Under two alternativeassumptions, one of which covers all previously considered cases,the first identity in the sequence is shown to imply the rest. 相似文献
158.
Unknotting Tunnels and Seifert Surfaces 总被引:2,自引:0,他引:2
Let K be a knot with an unknotting tunnel and suppose thatK is not a 2-bridge knot. There is an invariant = p/q Q/2Z,with p odd, defined for the pair (K, ). The invariant has interesting geometric properties. It is oftenstraightforward to calculate; for example, for K a torus knotand an annulus-spanning arc, (K, ) = 1. Although is definedabstractly, it is naturally revealed when K is put in thinposition. If 1 then there is a minimal-genus Seifert surfaceF for K such that the tunnel can be slid and isotoped to lieon F. One consequence is that if (K, ) 1 then K > 1. Thisconfirms a conjecture of Goda and Teragaito for pairs (K, )with (K, ) 1. 2000 Mathematics Subject Classification 57M25,57M27. 相似文献
159.
160.
Gaven J. Martin Volker Mayer 《Transactions of the American Mathematical Society》2003,355(11):4349-4363
We consider rigidity phenomena for holomorphic functions and then more generally for uniformly quasiregular maps.