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排序方式: 共有429条查询结果,搜索用时 15 毫秒
421.
D. Lillis F. Toolan A. Mur L. Peng R. Collier J. Dunnion 《Artificial Intelligence Review》2006,25(1-2):179-191
Information Retrieval (IR) forms the basis of many information management tasks. Information management itself has become
an extremely important area as the amount of electronically available information increases dramatically. There are numerous
methods of performing the IR task both by utilising different techniques and through using different representations of the
information available to us. It has been shown that some algorithms outperform others on certain tasks. Combining the results
produced by different algorithms has resulted in superior retrieval performance and this has become an important research
area. This paper introduces a probability-based fusion technique probFuse that shows initial promise in addressing this question. It also compares probFuse with the common CombMNZ data fusion technique. 相似文献
422.
Records (2263) from a single north Florida herd for 3 yr were evaluated in a series of analyses. Environment was subtropical. Data set included only cows that had normal milk records and became pregnant. Holsteins and Jerseys averaged 6799 and 4504 kg milk, 587 and 418 kg postpartum body weight, 164 and 141 days open, and 2.3 and 2.1 services per subsequent pregnancy. Pooled within breed, repeatabilities and heritabilities of these performance measures were .37, .15; .53, .25; .20, .06; and .30, 0. Estimable genetic correlations were milk yield and body weight -.09, milk yield and services per conception .38, and services per conception and body weight .37; range of standard errors was .22 to .39. Substantial genetic antagonism may exist between milk yield and body weight, and efficient reproduction. If results of this research are verified elsewhere, breeders should be aware that selection for increased weight could lead to decreased reproductive efficiency. 相似文献
423.
Jan‐Marten Seitz Kelly Collier Eric Wulf Dirk Bormann Friedrich‐Wilhelm Bach 《Advanced Engineering Materials》2011,13(9):B313-B323
The in vitro degradation of magnesium alloys with various alloying elements, the effect of coatings, and the impact of an altered experimental environment are investigated. LANd442 and Nd2 alloys are subjected to a continuously moving environment during an immersion test allowing flowing SBF. Applying an MgF2 coating to the alloys increases the corrosion resistance of LANd442 but has no effect on the corrosion rate of Nd2 within the period of investigation. It leads to a more‐even degradation with less pitting corrosion in the early stages of corrosion. A bioglass coating on Nd2 increases the corrosion rate. The mass loss, volume loss, and loss in maximum force all show the same trends as the specimens degrade over time. 相似文献
424.
N. Collier L. Dalcin V. M. Calo 《International journal for numerical methods in engineering》2014,100(8):620-632
We compare the computational efficiency of isogeometric Galerkin and collocation methods for partial differential equations in the asymptotic regime. We define a metric to identify when numerical experiments have reached this regime. We then apply these ideas to analyze the performance of different isogeometric discretizations, which encompass C0 finite element spaces and higher‐continuous spaces. We derive convergence and cost estimates in terms of the total number of degrees of freedom and then perform an asymptotic numerical comparison of the efficiency of these methods applied to an elliptic problem. These estimates are derived assuming that the underlying solution is smooth, the full Gauss quadrature is used in each non‐zero knot span and the numerical solution of the discrete system is found using a direct multi‐frontal solver. We conclude that under the assumptions detailed in this paper, higher‐continuous basis functions provide marginal benefits. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
425.
In this study, Southern pine (Pinus sp.) deck boards were machined to flat (control) and ribbed surface profiles. The specimens were treated with aqueous formulations of 4,5-dichloro-2-N-octyl-4-isothiazolin-3-one (EL2) and amine copper azole (CA-C) using a vacuum/pressure method. Boards were exposed to accelerated weathering for 576 h (24 days). The results showed all of the preservative-treated ribbed decking samples had a lower average number of checks compared to end matched flat samples. Checks were also shorter and narrower in the profiled deck boards than in the unprofiled specimens. Furthermore, the lowest amount of checking, cupping, twist and bowing was observed for specimens profiled and treated with the EL2. 相似文献
426.
Fitzgerald AC Annen-Dawson EL Baumgard LH Collier RJ 《Journal of dairy science》2007,90(12):5483-5489
We hypothesized that early-lactation increased milking frequency, in combination with bovine somatotropin (bST), would improve milk yield in continuously milked (CM) primiparous glands through greater mammary epithelial cell (MEC) function, proliferation, and reduced apoptosis (cell turnover). Primiparous cows were randomly assigned to a 2 × 2 × 2 factorial with a split-plot design to either a continuous bST (+bST, n = 4) or no bST (−bST, n = 4) treatment throughout the study. Within each animal, udder halves were randomly assigned to either a CM or a 60-d dry period (control). During late gestation, CM glands were milked twice daily until calving or until spontaneous dry-off. At calving, cows were milked either twice or 4 times daily and udder-half milk yield was recorded until 30 d postpartum. Mammary biopsies were conducted on −19 ± 13, −8 ± 6, +2, +7, and +20 d relative to calving. Postpartum milk yield was reduced in CM udder halves. Reduced milk yield in CM half udders from cows administered bST and milked 4 times daily was 35% compared with 65% in CM half udders in cows not provided bST and milked twice daily. Proliferation of MEC tended to be greater in control vs. CM tissue at 8 ± 6 d prepartum. Mammary epithelial cell proliferation was greater during the prepartum period (d −19, −8) compared with postpartum time points (d 2, 7, 20). Apoptosis of MEC was not affected by dry period length, but was elevated during the first 7 d postpartum compared with levels measured at −19, −8, and 20 d. Bovine somatotropin did not alter MEC turnover in primiparous CM or control glands. The use of increased milking frequency and bST alleviated, but did not prevent, reductions in milk yield of CM primiparous cows. 相似文献
427.
428.
Keri K. Stephens Courtney J. Powers Brett W. Robertson Lauryn A. Spearing John C. Collier Kendall P. Tich William R. Smith 《突发事故与危机管理杂志》2023,31(1):26-38
When a wildfire strikes, it impacts entire communities. Yet it can be challenging to get communities to take the lead in becoming more prepared, and thus build lasting resilience. Guided by theoretical preparedness models, and using a case study design, this study examines the planning, execution, and subsequent sensemaking around one of the first community-led wildfire evacuation drills in the United States. Findings illustrate the interplay between individual preparedness, communication, and community involvement as the neighbourhood studied conducted their drill in partnership with multiple emergency response organizations. Our model explains 39% of the variance in individuals' preparedness, finding that people with higher self-efficacy, more involved with the community, and who felt strong social norms around preparedness had more items prepared for a wildfire. The community's desire to share the preparedness organizing process with external audiences is a unique and important contribution in understanding how communication can be used to sustain community resilience. 相似文献
429.
This work is concerned with determining how to effectively recycle wholly thermoplastic composites comprised of a polypropylene (PP) matrix reinforced with a thermotropic liquid crystalline polymer (TLCP). A novel reclamation process was developed in which the TLCP could be recovered from the PP matrix. Reactive extrusion was used to reduce the molecular weight of the PP (Montell 6523) and to facilitate phase separation. The melt was then extruded into a heated mineral oil bath, which separated the TLCP (DuPont HX8000) from the matrix by dissolving the PP. It was found that greater than 70 wt% of the TLCP could be reclaimed from the PP matrix at a purity of greater than 96 wt%. In order to determine the ability to reuse the reclaimed HX8000, injection molded in situ composites were generated and their mechanical properties were determined. When the neat HX8000 component was partially replaced with reclaimed HX8000, the injection molded TLCP/PP composites showed no discernible difference in mechanical properties. 相似文献