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61.
62.
David G. James Robert J. Bartelt Richard J. Faulder 《Journal of chemical ecology》1994,20(11):2805-2819
Synthetic aggregation pheromones ofCarpophilus hemipterus (L.) andCarpophilus mutilatus Erichson were field tested during a 10-month period in southern New South Wales stone fruit orchards to determineCarpophilus spp. phenology and the effect of two pheromone doses on attraction. Aggregation pheromones synergize the attraction of host volatiles toCarpophilus spp. Four major species,C. hemipterus, C. mutilatus, C. davidsoni Dobson andC. (Urophorus) humeralis (F.), were trapped, with greater numbers of each species inC. hemipterus pheromone/fermenting whole-wheat breaddough-baited traps, than in dough-only-traps. InC. mutilatus pheromone/ fermenting-dough-baited traps, onlyC. mutilatus andC. davidsoni responded in greater numbers than to dough-only traps. Beetles first appeared in traps in late September (early spring) when daily maximum temperatures averaged 17.5C. Trappings reached a peak during October and declined to very low levels in November–December (late spring-early summer). Numbers trapped of all species increased during February–March (late summer–early autumn), presumably due to the presence of abundant host resources (ripening and fallen fruit), and continued at high levels until May (late autumn). An 18-week study demonstrated significantly greater responses byCarpophilus spp. to 5000-g than to 500-g doses of C.hemipterus andC. mutilatus pheromones. Greatest responses to 5000g were recorded forC. hemipterus andC. mutilatus responding to their own pheromones (increased attraction over dough alone of 259x and 21.2x respectively). Implications of the study and the potential for using synthetic aggregation pheromones for managingCarpophilus spp. populations in Australian stone fruit are discussed. 相似文献
63.
Richard T. Scalettar 《Journal of Low Temperature Physics》1995,99(3-4):499-504
In this paper we report the results of Quantum Monte Carlo (QMC) simulations of a tight binding, correlated electron model consisting of two 2D Hubbard sheets hybridized by an intersheet hopping t. As t increases, a ground state with long range antiferromagnetic order gives way to a spin liquid phase. 相似文献
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Richard Lobb 《The Visual computer》1996,12(8):373-389
This paper describes a method for rounding edges and corners of arbitrary polyhedra that uses a fast approximation to convolutional filtering. The approximation defines an implicit surface, which is rendered with a specialised ray-tracing algorithm. By varying the radius of the smoothing filter, a wide range of effects can be obtained, from perfect polyhedra to blobby models. Small rounding radii give polyhedra a softer, more natural look, with edges well delineated by shadows and highlights. The rounded surfaces are much easier to specify and compute than those obtained by traditional filleting and surface-blending techniques, and are far more economical in storage. 相似文献
66.
Richard J. Holden 《Cognition, Technology & Work》2011,13(1):11-29
According to the human factors paradigm for patient safety, health care work systems and innovations such as electronic medical
records do not have direct effects on patient safety. Instead, their effects are contingent on how the clinical work system,
whether computerized or not, shapes health care providers’ performance of cognitive work processes. An application of the
human factors paradigm to interview data from two hospitals in the Midwest United States yielded numerous examples of the
performance-altering effects of electronic medical records, electronic clinical documentation, and computerized provider order
entry. Findings describe both improvements and decrements in the ease and quality of cognitive performance, both for interviewed
clinicians and for their colleagues and patients. Changes in cognitive performance appear to have desirable and undesirable
implications for patient safety as well as for quality of care and other important outcomes. Cognitive performance can also
be traced to interactions between work system elements, including new technology, allowing for the discovery of problems with
“fit” to be addressed through design interventions. 相似文献
67.
We revisit the problem of determining confidence interval widths for the comparison of means. For the independent two-sample (two-sided) case, Goldstein and Healy (1995) draw attention to the fact that comparisons based on 95% error bars are not very effective in assessing the statistical significance of the difference in means and derive the correct confidence interval for such a comparison. We provide an extension to Goldstein and Healy (1995) to account for the correlation structure and unequal variances. We use the results to develop rules of thumb for evaluating differences, in an exploratory manner, like Moses (1987) and Cumming (2009), from the independent case. We illustrate the method for the simple comparison of two means in a real data set, provide R code that may be easily implemented in practice, and discuss the extension of the method to other applied problems. 相似文献
68.
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70.
In this paper, we present a thorough mathematical analysis of the use of neural networks to solve a specific classification
problem consisting of a bilinear boundary. The network under consideration is a three-layered perceptron with two hidden neurons
having the sigmoid serving as the activation function. The analysis of the hidden space created by the outputs of the hidden
neurons will provide results on the network’s capacity to isolate two classes of data in a bilinear fashion, and the importance
of the value of the sigmoid parameter is highlighted. We will obtain an explicit analytical function describing the boundary
generated by the network, thus providing information on the effect each parameter has on the network’s behavior. Generalizations
of the results are obtained with additional neurons, and a theorem concerned with analytical reproducibility of the boundary
function is established. 相似文献