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91.
A dual read-out model of context effects in letter perception is described that predicts forced-choice accuracy in the Reicher paradigm and its relation to word reportability. It is hypothesized that a correct choice to a letter in a word context is made when either the correct letter representation or a word representation containing the correct letter in the correct position reaches a response threshold (a criterion level of activation). This hypothesis was implemented using the basic architecture of the interactive activation model (J. L. McClelland & D. E. Rumelhart, 1981) in its semistochastic variant (A. M. Jacobs & J. Grainger, 1992). The model successfully captures the data of J. C. Johnston (1978), otherwise thought to be critically damaging for this type of model, and accurately predicts performance in a series of new experiments using the Reicher paradigm. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
92.
93.
MuShanxiang JiXiaoli LiMing LiXingguo 《电子科学学刊(英文版)》2003,20(6):407-413
Linear Modulated Frequency (LMF) Costas Stepped Frequency Radar (SFR) signal is introduced. Its ambiguity function is derived and analyzed in detail and its feasibility is validated in theory. The scheme of the proposed signal processing is also presented. The results of theoretic analysis and simulation show that, by using the proposed signal and increasing the bandwidth of the total stepped frequency, the ambiguity sidelobe is well suppressed and the range-velocity coupling in the stepped frequency radar is also greatly weakened. 相似文献
94.
Revisiting neighbourhood change from a Canadian perspective: Some supporting evidence from Vancouver
This paper argues that the several models of neighbourhood change developed in the United States are generally not applicable to Canadian cities due to differences in urban form, socioeconomic characteristics, and a host of institutional factors. A simple model is presented which extends the arbitrage model of neighbourhood dynamics. Several hypotheses are advanced and then tested on a data base covering three Vancouver, B.C. neighbourhoods from 1955 to 1981 by estimating several hedonic price equations. The hypotheses receive partial support. Implications for policymakers are then discussed.We wish to thank Jim Fitzsimmons and Judy Fountain for their computer assistance and the British Columbia Assessment Authority for providing us with data. Helpful comments on an earlier version of this paper were provided by Lawrence Jones and Douglas Diamond. We also like to acknowledge the financial support of the Canada Mortgage and Housing Corporation, the Real Estate Council of British Columbia, the University of British Columbia and the British Columbia Youth Employment Program. 相似文献
95.
Joannie W. Chin Eric Byrd Ned Embree Jonathan Martin J. D. Tate 《Journal of Coatings Technology》2002,74(929):39-44
Laboratory ultraviolet (UV) chambers are widely used to obtain weathering data for a wide range of commercial polymer products
including coatings, textiles, elastomers, plastics, and polymeric composites. Although numerous improvements have been made
in the design of UV chambers over the last 80 years, the reproducibility of the exposure results from these chambers has remained
elusive. This lack of reproducibility is attributed to systematic errors in their design, operation, and control which prevent
direct comparisons of the performance of materials exposed in the same environment, comparisons of the performance of the
same material exposed in different laboratories, and the comparison of field and laboratory results. This paper describes
an innovative UV chamber design based on integrating sphere technology that greatly reduces the magnitude of these errors,
as well as provides additional experimental capabilities.
Presented at the 79th Annual Meeting of the Federation of Societies for Coatings Technology, on November 4–7, 2001, in Atlanta,
GA.
Building Materials Division. Gaithersburg, MD.
Freeport, TX. 相似文献
96.
97.
Jonathan Cherneff Robert Logcher Jerome Connor Nicholas Patrikalakis 《Research in Engineering Design》1992,3(4):195-210
A method for machine interpretation of architectural (or other) schematic drawings is presented. The central problem is to build an efficient drawing parser (i.e., a program that identifies the semantic entities, characteristics, and relationships that are represented in the drawing). The parser is built from specifications of the drawing grammar and an underlying spatial model. The grammar describes what to look for, and the spatial model enables the parser to find it quickly. Coupled with existing optical recognition technology, this technique enables the use of drawings directly as: (1) a database to drive various Architecture-Engineering-Construction (AEC) applications; (2) a communication protocol to integrate CAD systems; (3) a traditional user interface. 相似文献
98.
Jonathan Alexander Author Vitae William P. Banks Author Vitae 《Computers and Composition》2004,21(3):273-293
In this introduction to a special issue of Computers and Composition, the authors critically review current literature on computer-assisted writing pedagogies that grapple with issues of sexuality. Although this body of work is small, it points to provocative ways to develop our students’ critical and rhetorical sensibilities about the constructions of sexuality in our culture. Further, such work innovatively addresses the place of networked communication technologies in the interrogation of such constructions. The authors conclude with both an introduction of the work in this special issue that addresses the intersection of sexuality studies and computer-assisted writing studies and with a call for additional work in this field. 相似文献
99.
Courtney Marrett Alexandre Moulart Jonathan Colton Abbas Tcharkhtchi 《Polymer Engineering and Science》2003,43(4):822-830
The dielectric properties of a ceramic powder (BaTiO3) filled thermoplastic elastomer (EPDM TPE) were investigated for use in a flexible electromagnetic crystal. Materials were produced that had a high dielectric constant (approximately 9) and low loss tangent (less than 0.01). Materials were extruded and injection molded so as to povide low‐cost processing. Mechanical and electromagnetic test results showed the effect of processing conditions on the final quality of the composite. The shear rate during processing and the number of mixing cycles were found to affect the final material characteristics significantly. An electromagnetic crystal woven from extruded rods showed good reflectivity in the 10–15 GHz region. 相似文献
100.