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51.
Object-oriented design is an approach to systems development that proposes the use of system objects to build new systems and rebuild old ones. An important goal of object-oriented development is to change the nature of traditional software development from designing and writing models from scratch to building systems through the assembly of reusable software objects. This article discusses the productivity potential as well as the limitations of object-oriented systems development and makes recommendations for its use.  相似文献   
52.
保证所有管道中石油从一端流向另一端不泄漏要比它的探测更加困难。比较图中的3个系统,可以看到这项技术在40多年来是如何逐步发展的。  相似文献   
53.
Mutual Information (MI) is popular for registration via function optimisation. This work proposes an inverse compositional formulation of MI for Levenberg-Marquardt optimisation. This yields a constant Hessian, which may be pre-computed. Speed improvements of 15% were obtained, with convergence accuracies similar to those of the standard formulation.  相似文献   
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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   
56.
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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58.
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   
59.
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   
60.
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   
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