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11.
12.
We consider a two-chain exponential queueing network with a large number of customers that consists of one infinite-server (IS) station and two processor-sharing (PS) or FCFS single-server stations. The asymptotic behavior of the partition function is studied for such a network when one or both PS (FCFS) nodes are heavily loaded. The results are derived using methods of multidimensional complex analysis (the theory of homologies and residues) and the saddle-point method. 相似文献
13.
Yaakov Ben Natan Yoav Benyamini H»kan Hendenmalm Yitzhak Weit 《Arkiv f?r Matematik》1996,34(2):199-224
Our main result gives necessary and sufficient conditions, in terms of Fourier transforms, for an ideal in the convolution
algebra of spherical integrable functions on the (conformal) automorphism group of the unit disk to be dense, or to have as
closure the closed ideal of functions with integral zero. This is then used to prove a generalization of Furstenberg's theorem,
which characterizes harmonic functions on the unit disk by a mean value property, and a “two circles” Morera type theorem
(earlier announced by Agranovskii).
The second author's work was partially supported by the fund for the promotion of research at the Technion-Israel Institute
of Technology. The third author's work was partially supported by the Swedish Natural Science Research Council, and by the
1992 Wallenberg Prize from the Swedish Mathematical Society. 相似文献
14.
Yaakov S. Kupitz 《Discrete Mathematics》2008,308(23):5485-5498
We give sufficient (and necessary) conditions of local character ensuring that a geometric graph is the 1-skeleton of an unstacked triangulation of a simple polygon. 相似文献
15.
Usually the Lorentz transformations are derived from the conservation of the spacetime interval. We propose here a way of obtaining spacetime transformations between two inertial frames directly from symmetry, the isotropy of the space and principle of relativity. The transformation is uniquely defined except for a constant e, that depends only on the process of synchronization of clocks inside each system. Relativistic velocity addition is obtained, and it is shown that the set of velocities is a bounded symmetric domain. If e=0, Galilean transformations are obtained. If e>0, the speed 1/e and a spacetime interval are conserved. By assuming constancy of the speed of light, we get e=1/c
2 and the transformation between the frames becomes the Lorentz transformation. If e<0, a proper speed and a Hilbertian norm are conserved. 相似文献
16.
This Letter reports on the experimental implementation of the quantum baker's map via a three bit nuclear magnetic resonance quantum information processor. The experiments tested the sensitivity of the quantum chaotic map to perturbations. In the first experiment, the map was iterated forward and then backward to provide benchmarks for intrinsic errors and decoherence. In the second set of experiments, the least significant qubit was perturbed in between the iterations to test the sensitivity of the quantum chaotic map to controlled perturbations. These experiments can be used to investigate existing theoretical predictions for quantum chaotic dynamics. 相似文献
17.
We identify a border between regular and chaotic quantum dynamics. The border is characterized by a power-law decrease in the overlap between a state evolved under chaotic dynamics and the same state evolved under a slightly perturbed dynamics. For example, the overlap decay for the quantum kicked top is well fitted with [1+(q-1)(t/tau)2](1/(1-q)) (with the nonextensive entropic index q and tau depending on perturbation strength) in the region preceding the emergence of quantum interference effects. This region corresponds to the edge of chaos for the classical map from which the quantum chaotic dynamics is derived. 相似文献
18.
Kirubarajan T. Chen Huimin Bar-Shalom Yaakov 《Methodology and Computing in Applied Probability》2001,3(4):387-410
Parameter estimation in the presence of false measurements due to false alarms and missed true detections, i.e., in the presence of measurement origin uncertainty, is a difficult problem because of the need for data association, the process of deciding which, if any, is the true measurement and which are false. An additional aspect of estimation is performance evaluation via, for example, the Cramer-Rao Lower Bound (CRLB), which quantifies the achievable performance. With measurement origin uncertainty and the ensuing data association, the CRLB has to be modified to account for the loss of information due to false alarms and missed true detections. This is the focus of our paper—we show that the loss of information can be accounted for by a single scalar, known as the information reduction factor, under certain conditions. We illustrate the evaluation of the generalized CRLB on parameter estimation from direction-of-arrival measurements with applications to target tracking, communications and signal processing. Simulation results on a realistic scenario show that the lower bounds quantified via the information reduction factor are statistically compatible with the observed errors. 相似文献
19.
Steven Jackel Avi Meir Zvi Horvitz Inon Moshe Yehoshua Shimoni Yaakov Lumer Revital Feldman Izhak Hershko Yotam Pekin 《Optics & Laser Technology》2011,43(3):687-696
In this paper we investigate the source of failure in commercial, microchannel cooled CW diode bars placed in 12 bar horizontal arrays. The arrays were used to pump Nd:YAG rods in our 10 kW developmental laser. The laser was operated at low duty factor over a period of over 2 years. Experimental evidence indicated that the sudden, catastrophic failure was because of degraded cooling. We used optical microscopes, an X-ray microfocus imager, and a thermal neutron scattering camera to look inside the microcoolers. Our investigations revealed only one possible failure mechanism: cooling flow reduction because of delamination of the Au coating the walls of the microcoolers and the entrapment of Au flakes within the microchannel structures. We observed blisters in the microcoolers under working bars, and flake-like structures in the microcoolers under burnt-out bars (all taken from the laser). We observed no evidence of either massive blockages because of electrochemical deposits, or of corrosion/erosion in the microchannel walls. Integral operation times of the high flow-rate cooling system and of the diodes themselves were too short by one and two orders of magnitude, respectively, to explain the observed failures. Microchannel immersion times in the deionized water were, however, long enough to allow for corrosion of metals that may have been exposed through defects in the Au coatings. Three-dimensional heat flow simulations showed that blockage of multiple microchannels towards the edge of a bar can easily lead to catastrophic temperature increases. 相似文献
20.
Yaakov S. Kupitz 《Discrete Mathematics》1993,120(1-3):121-134
It is shown that, except for two well defined configurations, any finite set
with exactly three points on ∂V is the vertex set of a triangulation of [V] which is combinatorially the Schlegel diagram of a simplicial unstacked 3-polytope. 相似文献