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排序方式: 共有278条查询结果,搜索用时 9 毫秒
1.
Lasers containing a nanopatterned active layer demonstrating excellent threshold characteristics are presented. The nanopatterned active layer is fabricated using high-resolution electron beam lithography and selective-area metal organic chemical vapour deposition crystal growth. Results demonstrating an order of magnitude improvement over previous results are reported. 相似文献
2.
Bryce J. Stokes 《Biomass & bioenergy》1992,2(1-6):131-147
Eight countries collaborated and shared technical information on the harvesting of small trees and forest residues in a three year program. Proceedings and reports from workshops and reviews are summarized in a review of activities and harvesting systems of the participating countries. Four databases were developed for harvesting and transportation of these materials. 相似文献
3.
Lullo G. McKee A. McLean C.J. Bryce A.C. Button C. Marsh J.H. 《Electronics letters》1994,30(19):1623-1625
Electroabsorption optical modulators have been fabricated on GaInAs/GaInAsP multiquantum well structures whose bandgap had been increased by laser photoabsorption-induced disordering. Modulation depths of 20 dB have been obtained in material which has been bandgap blue shifted by as much as 120 nm, while samples shifted by 80 nm gave depths as high as 27 dB 相似文献
4.
J. H. Marsh S. A. Bradshaw A. C. Bryce R. Gwilliam R. W. Glew 《Journal of Electronic Materials》1991,20(12):973-978
Impurity induced disordering of GaInAs quantum well structures with barriers of AlGaInAs and of GaInAsP has been investigated
using boron and fluorine. The impurities were introduced by ion implantation followed by thermal annealing. Annealing unimplanted
P-based quaternary material at temperatures greater than 500° C caused a blue shift of the exciton peak. At annealing temperatures
greater than 650° C red shifts in the exciton peak of unimplanted Al-based quaternary material were observed. Boron implantation
caused small blue shifts of the exciton peak in both material systems at low annealing temperatures. Much larger blue shifts
were observed in the fluorine implanted samples. 相似文献
5.
Gabriel LaPlante Andrew E. Marble Bryce MacMillan Pearl Lee-Sullivan Bruce G. Colpitts Bruce J. Balcom 《NDT & E International》2005,38(6):501-507
Water ingress inside honeycomb sandwich panels during service has been linked to in-flight failure in some aircraft. There is an ongoing effort to develop nondestructive testing methods to detect the presence of water within the panels. Magnetic resonance (MR) represents an attractive approach in that it is sensitive to moisture. Using a unilateral MR sensor, testing can be applied directly to the surface of the panel. The viability of MR is demonstrated through laboratory imaging of both water within sandwich panels, as well as the adhesive itself. The detection of water using a one-sided handheld MR sensor is presented. It is shown that simple detection, as well as spatial localization of water within sandwich panels is possible. 相似文献
6.
Some of the current best conformant probabilistic planners focus on finding a fixed length plan with maximal probability. While these approaches can find optimal solutions, they often do not scale for large problems or plan lengths. As has been shown in classical planning, heuristic search outperforms bounded length search (especially when an appropriate plan length is not given a priori). The problem with applying heuristic search in probabilistic planning is that effective heuristics are as yet lacking.In this work, we apply heuristic search to conformant probabilistic planning by adapting planning graph heuristics developed for non-deterministic planning. We evaluate a straight-forward application of these planning graph techniques, which amounts to exactly computing a distribution over many relaxed planning graphs (one planning graph for each joint outcome of uncertain actions at each time step). Computing this distribution is costly, so we apply Sequential Monte Carlo (SMC) to approximate it. One important issue that we explore in this work is how to automatically determine the number of samples required for effective heuristic computation. We empirically demonstrate on several domains how our efficient, but sometimes suboptimal, approach enables our planner to solve much larger problems than an existing optimal bounded length probabilistic planner and still find reasonable quality solutions. 相似文献
7.
8.
Lihua Ran Curtis Dyreson Anneliese Andrews Renée Bryce Christopher Mallery 《Information and Software Technology》2009,51(2):460-477
Many organizations rely on web applications that use back-end databases to store important data. Testing such applications requires significant effort. Manual testing alone is often impractical, so testers also rely on automated testing techniques. However, current automated testing techniques may produce false positives (or false negatives) even in a perfectly working system because the outcome of a test case depends on the state of the database which changes over time as data is inserted and deleted. The Automatic Database Tester (AutoDBT) generates functional test cases that account for database updates. AutoDBT takes as input a model of the application and a set of testing criteria. The model consists of a state transition diagram that shows how users navigate pages, a data specification that captures how data flows, and an update specification that shows how the database is updated. AutoDBT generates guard queries to determine whether the database is in a state conducive to performing and evaluating tests. AutoDBT also generates partial oracles to help validate whether a back-end database is updated correctly during testing. This paper describes the design of AutoDBT, a prototype implementation, several experiments with the prototype, and four case studies. 相似文献
9.
10.
This paper describes the combustion properties of the amino‐substituted guanidinium 4,4′,5,5′‐tetranitro‐2,2′‐biimidazolate (N4BIM) series, including the bis‐mono, di and triaminoguanidinium salts. These salts are of interest as propellant ingredient additives, and in particular, the bis‐triaminoguanidinium salt of N4BIM displays excellent burn rate and combustion behavior. Our combustion studies have shown that TAGN4‐BIM displays a fast burning rate and has the lowest pressure dependence exponent yet measured for a triaminoguanidinium salt. 相似文献