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61.
William Faulkner's non-chronological story tellingstyle has long been a challenge to critics and apuzzle to beginning literature students. ``A Rose forEmily,' one of Faulkner's most frequently anthologizedstories, exemplifies the complexity of Faulkner'streatment of time. In this paper, we apply aconstraint-based problem solving method to an analysisof the chronology of ``A Rose for Emily.' Constraintlogic programming is a declarative programminglanguage paradigm that solves problems by enforcingconstraints among variables. CLP's ability to sortnumeric variables that do not yet have definite valuesmakes it possible to sort the events of ``A Rose forEmily' with only fragmented and relative timeinformation. In attempting to sort the events of thestory, we find an inconsistency in the temporalreferences scattered throughout the narrative. Afterremoving this inconsistency, we are able to compareour chronology with earlier ones and discuss thethematic relevance of Faulkner's nonlinear plots. 相似文献
62.
Disruption-tolerant networks (DTNs) differ from other types of networks in that capacity is created by the movements of network participants. This implies that understanding and influencing the participants’ motions can have a significant impact on network performance. In this paper, we introduce the routing protocol MORA, which learns structure in the movement patterns of network participants and uses it to enable informed message passing. We also propose the introduction of autonomous agents as additional participants in DTNs. These agents adapt their movements in response to variations in network capacity and demand. We use multi-objective control methods from robotics to generate motions capable of optimizing multiple network performance metrics simultaneously. We present experimental evidence that these strategies, individually and in conjunction, result in significant performance improvements in DTNs. 相似文献
63.
Expert classification systems have proven themselves effective decision makers for many types of problems. However, the accuracy of such systems is often highly dependent upon the accuracy of a human expert's domain theory. When human experts learn or create a set of rules, they are subject to a number of hindrances. Most significantly experts are, to a greater or lesser extent, restricted by the tradition of scholarship which has preceded them and by an inability to examine large amounts of data in a rigorous fashion without the effects of boredom or frustration. As a result, human theories are often erroneous or incomplete. To escape this dependency, machine learning systems have been developed to automatically refine and correct an expert's domain theory. When theory revision systems are applied to expert theories, they often concentrate on the reformulation of the knowledge provided rather than on the reformulation or selection of input features. The general assumption seems to be that the expert has already selected the set of features that will be most useful for the given task. That set may, however, be suboptimal. This paper studies theory refinement and the relative benefits of applying feature selection versus more extensive theory reformulation. 相似文献
64.
Ian Hamerton John N. Hay Brendan J. Howlin John R. Jones Shui-Yu Lu Graham A. Webb Michael G. Bader 《Polymer Bulletin》1997,38(4):433-438
We report a study of the curing mechanism of 13C labelld bisphenol A dicyanate ester in the presence of a electrolytically surface treated XAS carbon fibre using several
techniques – solid state 13C NMR, scanning electron microscopy (SEM) and diffuse reflectance FTIR. Comparison of the results obtained in pure matrices
and solution shows that the resin undergoes the same reaction mechanism in both cases and forms the sym-triazine network structure in the composite.
Received: 25 November 1996/Accepted: 23 January 1997 相似文献
65.
Using the example of a real product, this paper shows how various usability assessments, conducted by different human factors engineers, in several phases of the product's development life-cycle, identified similar potential usability problems. Circumstances dictated that no remedial action was taken, so it was possible to track these potential usability defects to customer sites, where it was found that most of the important problems did indeed occur. Thus, it can be demonstrated that human factors advice was valid and reliable. In simpler terms, early usability evaluation by human factors engineers can save hours of wasted development effort and customer frustration, and can help to ensure that a more usable product is produced. 相似文献
66.
Gordon J. Thorogood Brendan J. Kennedy Ray L. Withers 《Materials Research Bulletin》2008,43(4):787-795
The structure of the defect pyrochlore CsTi0.5W1.5O6 has been investigated using electron, synchrotron X-ray and neutron diffraction methods. The material is cubic a = 10.2773 Å with displacive disorder of the Cs cations along the 〈1 1 1〉 direction. The local structure, revealed by the diffuse structure in the electron diffraction patterns shows there is correlated displacement of the heavy Cs atoms along the 〈1 1 0〉 directions. The thermal expansion of the material is also described. 相似文献
67.
William Faulkner's non-chronological story tellingstyle has long been a challenge to critics and apuzzle to beginning literature students. ``A Rose forEmily,'' one of Faulkner's most frequently anthologizedstories, exemplifies the complexity of Faulkner'streatment of time. In this paper, we apply aconstraint-based problem solving method to an analysisof the chronology of ``A Rose for Emily.'' Constraintlogic programming is a declarative programminglanguage paradigm that solves problems by enforcingconstraints among variables. CLP's ability to sortnumeric variables that do not yet have definite valuesmakes it possible to sort the events of ``A Rose forEmily'' with only fragmented and relative timeinformation. In attempting to sort the events of thestory, we find an inconsistency in the temporalreferences scattered throughout the narrative. Afterremoving this inconsistency, we are able to compareour chronology with earlier ones and discuss thethematic relevance of Faulkner's nonlinear plots. 相似文献
68.
This paper presents 38-GHz wide-band point-to-multipoint measurement results from various weather events. 73963 measured power delay profiles indicate that multipath can occur due to the foliage and the reflection from wet surfaces during rain. The received signal strength during rain varies according to a Rician distribution with a K factor inversely proportional to the rain rate. The measured rain attenuation exceeds Crane's model prediction by several decibels. The results may aid in design of broadband millimeter-wave communication systems 相似文献
69.
70.
Steven Boyle 《电子元器件资讯》2010,(10)
目前,混合动力汽车(HEV)、插电式混合动力汽车(PHEV)和纯电动汽车(EV)的开发工作与锂离子(Li-ion)电池的使用密不可分,许多OEM、电子设备供应商和电池制造商探讨的重点都集中在如何构建最佳的电池监控和管理系统.这些系统当然需要一个主监控器,它通常是一个与微控制器或电池管理单元(BMU)接口的模数转换器(ADC),用来提供精确的测量数据并执行电池平衡(确保充电前所有电池处于同一电平). 相似文献