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361.
Manhattan’s 1811 street grid defined the spatial framework for urbanization. Existing scholarship, however, has not empirically examined its role in determining land-use geography. By mid-nineteenth century, New York City had grown substantially into its street system, but had not yet instituted comprehensive zoning regulations. We explore interactions between the grid’s morphology and land-use placement on the street in a generally unregulated environment, comparing patterns in the city’s pre- and post-grid halves. Deploying new GIS data and methods, we complement existing interpretations showing that the grid guided Manhattan’s development towards mixed-use commercial and residential avenues with residential and industrial cross-streets. We demonstrate that one set of locational logics drove these patterns pre- and post-grid. The grid amplified the morphological parameters of land use, identified as street connectivity, length, and width. Connectivity, determined by block dimensions, constituted the most critical factor. Lastly, we suggest that our findings and methods on the interactions between street morphology and land use are relevant to other cities, both for historical research and contemporary planning practice. 相似文献
362.
Buchler Norbou G.; Faunce Paige; Light Leah L.; Gottfredson Nisha; Reder Lynne M. 《Canadian Metallurgical Quarterly》2011,26(1):111
Young and older adults studied word pairs and later discriminated studied pairs from various types of foils including recombined word-pairs and foil pairs containing one or two previously unstudied words. We manipulated how many times a specific word pair was repeated (1 or 5) and how many different words were associated with a given word (1 or 5) to tease apart the effects of item familiarity from recollection of the association. Rather than making simple old/new judgments, subjects chose one of five responses: (a) Old-Old (original), (b) Old-Old (rearranged), (c) Old-New, (d) New-Old, (e) New-New. Veridical recollection was impaired in old age in all memory conditions. There was evidence for a higher rate of false recollection of rearranged pairs following exact repetition of study pairs in older but not younger adults. In contrast, older adults were not more susceptible to interference than young adults when one or both words of the pair had multiple competing associates. Older adults were just as able as young adults to use item familiarity to recognize which word of a foil was old. This pattern suggests that recollection problems in advanced age are because of a deficit in older adults' formation or retrieval of new associations in memory. A modeling simulation provided good fits to these data and offers a mechanistic explanation based on an age-related reduction of working memory. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
363.
Suppression of phase ambiguity in digital holography by using partial coherence or specimen rotation
In this paper we present two approaches for extracting the surface profile as well as obtaining 3D imaging of near field objects by usage of partial coherence and digital holography. In the first approach a light source with given temporal partial coherence is used to illuminate a near field object. The reflected light is interfered with the reference source. By computing the local contrast of the generated fringes one may estimate the 3D topography and the profile of the object. This approach extracts the 3D information from a single image, and its accuracy does not depend on triangulation angle like in fringe projection methods. The second approach is tomography based. There we illuminate the object from several slightly different angles, and for each we compute the wrapped phase using digital holography techniques. Combining the wrapped phase estimation from several points of projection allows calculating the unwrapped phase and therefore the true profile of even a phase-only object. Increasing the number of points of view decreases the relative error of the estimated profile. 相似文献
364.
Fourier transform infrared (FT-IR) attenuated total reflection (ATR) spectroscopy was used to discriminate five commonly encountered soil-borne fungi that cause severe economic damage to agriculture: Colletotrichum, Fusarium, Pythium, Rhizoctonia, and Verticillium. Contrary to previous studies related to microorganism discrimination using FT-IR-ATR spectroscopy, the pathogen samples were not dried on the ATR crystal, which is a time-consuming operation. Rather, after removing some pathogen filaments from the solution using tweezers, these were placed directly on a flat ATR crystal and pressure was applied using a pressure clamp. Following water subtraction, baseline correction, and normalization of the spectra, principal component analysis was used as a data-reduction step and canonical variate analysis was used for discrimination. Discrimination was performed at the genus level and at the strain level for Colletotrichum. For discrimination between the five fungi at the genus level, the success rate for the validation samples ranged from 75% to 89%. For discrimination between the two Colletotrichum strains, the success rate was 78%. Comparison with spectra of similar fungi dried on the ATR crystal showed that both types of spectra were very similar, indicating that drying the samples on the ATR crystal is not required and can be replaced by mathematical post-processing of the spectra. For routine analyses that involve rapid screening of very large amounts of samples, this approach allows for increasing significantly the number of samples that can be analyzed daily. 相似文献
365.
Goodlet Brent R. Mills Leah Bales Ben Charpagne Marie-Agathe Murray Sean P. Lenthe William C. Petzold Linda Pollock Tresa M. 《Metallurgical and Materials Transactions A》2018,49(6):2324-2339
Metallurgical and Materials Transactions A - Bayesian inference is employed to precisely evaluate single crystal elastic properties of novel $$gamma -gamma '$$ Co- and CoNi-based superalloys... 相似文献