Showing papers by "AT&T Labs published in 1994"
Journal Article•
TL;DR: In this paper, the authors consider multiple-server polling systems, in which each server visits the queues according to its own cyclic schedule, and derive waiting-time approximations for asymmetric systems with the exhaustive and gated service discipline.
Abstract: We consider multiple-server polling systems, in which each of the servers visits the queues according to its own cyclic schedule. Such systems appear to completely defy the derivation of exact waiting-time results, which motivates the search for accurate approximations. In the present paper, we derive waiting-time approximations for asymmetric systems with the exhaustive and gated service discipline. The approximations are tested for a wide range of parameter combinations.
23 citations
TL;DR: In this paper, the authors achieved greater than 150°C CW lasing from an unbonded GaAs/AlGaAs VCSEL by employing high barrier confinement spacers and by blue shifting the optical gain.
Abstract: Greater than 150°C CW lasing is achieved from an unbonded GaAs/AlGaAs VCSEL by employing high barrier confinement spacers and by blue shifting the optical gain. This is done while maintaining a variation in threshold current of only ±0.93 mA over a range greater than 150°C. These results are compared to a low barrier VCSEL of similar design.
11 citations
Proceedings Article•
13 Oct 1994TL;DR: In this article, a form of divide and conquer recursion on sets, together with relational algebra, is used to express the queries over ordered relational databases which are NC-computable.
Abstract: We show that a form of divide and conquer recursion on sets, together with the relational algebra, expresses exactly the queries over ordered relational databases which areNC-computable At a finer level, we relateknested uses of recursion exactly toACk,k?1 We also give corresponding results for complex objects
8 citations