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71.
72.
Abstract A long history of overt discrimination left an enduring racialized imprint upon the geography of the East Bay. While the benefits of a metropolitan decentralization of jobs, housing, and public investment fell to Whites, discrimination in employment and housing trapped African Americans in urban neighborhoods burdened by infrastructure encroachment and divestment. By circa 1970, overt discrimination succumbed to new, racially neutral, legal, and administrative forms, including regional planning processes. Using an environmental racism framework, we show that these new forms reproduced the existing racialized geography by means of new inequalities in representation and transportation service provision. These new regional transportation policies, like those challenged by a 2005 civil rights lawsuit, favored the mobility needs of more affluent suburbanites over those of African American East Bay bus riders. These policies, layered onto an existing racialized geography, reinforced existing inequalities by failing to address racial barriers to opportunity in the built environment. [Key words: transportation, race, segregation, Oakland] 相似文献
73.
O. V. Dudnik M. Prieto E. V. Kurbatov S. Sanchez T. G. Timakova A. V. Spassky V. N. Dubina P. Parra 《Solar System Research》2013,47(1):58-65
The design concept and first set of results are presented for electronic modules of a laboratory prototype of the small-size satellite instrument SIDRA intended for measurements of charged particle fluxes in outer space. The working prototype consists of a detector assembly based on high-purity silicon and fast scintillation detectors, modules of analogue and digital processing, and a secondary power supply module. The first results are discussed of a Monte-Carlo simulation of the instrument with the use of the GEANT4 toolkit and of measurements of the main parameters of charge-sensitive pre-amplifiers, shapers, and peak detectors. Results of calibration measurements with the use of radioactive sources and beams of accelerated charged particles are presented. 相似文献
74.
75.
The ANELFA scale for hailfall intensity is proposed on the model of the 6-class Fujita scale for tornadoes. It is based on more than three thousand point hailfalls measured by hailpads over a 16-year period in France. The class number of a hailfall is determined by the integer value of the largest measured hailstone diameter in cm, or by equivalence with current objects: A0 to A5 for pea, grape, pigeon's egg, walnut, hen's egg, orange. The class number is followed by a plus or minus sign if the ground is significantly more or less than half-covered by hailstones respectively. When the scale is applied to the ANELFA data, a log-normal distribution is found for the class distribution, allowing the frequency determination of the upper class ever observed until now at the hailpad stations. 相似文献
76.
Luiz Alberto Ribeiro Mendonça Horst Frischkorn Marlúcia Freitas Santiago Josué Mendes Filho 《Environmental Geology》2005,47(8):1045-1053
Measurements of the environmental isotopes carbon-14 and oxygen-18 and of the electrical conductivity in ground water, together with MODFLOW-88 (DOS) simulations of pumping tests, were used to achieve a detailed understanding of the functioning of an aquifer in the area of a well field. The methodology was applied in the sedimentary basin of the Cariri region, in the south of Ceará State in Brazil. Localized hydraulic connections between adjacent aquifer units could be detected, and mixing ratios for the contributions from the units involved were determined. Cone of depression simulations for a three-year drought period revealed well interference and a drastic lowering of the piezometric level, thereby explaining the hydrogeologic changes and transformations in vegetation that were observed in the area of the well field. The combined use of the modeling tools and the geochemical field observations is shown to provide more detailed insight into the conceptual model of the groundwater flow system. 相似文献
77.
José S. Carrión Elena Fierro Milagros Ros Manuel Munuera Santiago Fernández Juan Ochando Gabriela Amorós Francisca Navarro Tomás Rodríguez-Estrella Saúl Manzano Penélope González-Sampériz Ana Moreno 《Proceedings of the Geologists' Association. Geologists' Association》2018,129(4):512-525
This paper presents a new Holocene palaeoecological record from coastal south-eastern Spain, a region characterised by high plant species diversity, varied physiography, high risk of desertification, and a history of human pressure on the landscape that stretches to antiquity. The pollen sequence shows four main vegetation phases: the first characterised by mixed forests of Pinus and evergreen Quercus accompanied by broad-leaved mesophilous trees, and a diversity of Mediterranean scrub; the second phase is characterised by mesophytic decline and expansion of Artemisia; a third, mid-Holocene phase of thermo-mesophytic maxima with prevalence of forested landscapes; and, finally, the progressive opening of the landscape with sparse pines, halo-xerophytic grasslands and sclerophyllous brushwood. The current treeless situation of south-eastern Spain is a relatively recent feature resulting from a dramatic change in the ecological structure of the regional landscapes. This paper stresses the continued vulnerability of these arid systems in the face of a changing climate. This sequence adds to previous palaeobotanical records (pollen and charcoal) and archaeological reports to suggest that deforestation started earlier in low-elevation areas and river basins than in the inland mountains and platforms, a factor that appears in connection to human exploitation of the natural environment. 相似文献
78.
Elena Roget Iossif Lozovatsky Xavier Sanchez Manuel Figueroa 《Progress in Oceanography》2006,70(2-4):126
Modern approaches to microstructure data processing, including wavelet denoising, are discussed. The wavelet procedure is applied to small-scale shear signals before estimating the dissipation rate ε and to the temperature/density profiles used to calculate Thorpe scales. Microstructure data obtained on the Mediterranean shelf of Catalonia are used to illustrate various approaches to the Thorpe displacement calculations. It is suggested that the Weibull probability function is an appropriate model for the Thorpe scale distribution. Microstructure measurements from the upper layer of the Boadella reservoir (Catalonia, Spain) support this finding.A new analytical approximation for the 1D Panchev–Kesich spectrum is deduced and the results of ε computation are compared with spectral fitting by the widely used Nasmyth spectrum. Applying the Kraichnan spectral model to compute ε from temperature spectra in the convective-viscous sub-range is examined as an alternative to the Batchelor spectrum. Microstructure measurements taken in Lake Banyoles (Catalonia, Spain) and in the North Atlantic were used for spectral calculations.Statistical analysis of eddy Kb and thermal Kθ diffusivities measured on a shallow shelf of the Black Sea shows the importance of process-orientated domain averaging of the diffusivities in obtaining good correspondence between Kb and Kθ in active turbulent regions. In weakly turbulent, stratified interior layers, the averaged Kb and Kθ differ significantly, which may point to the inapplicability of isotropic formulae used for ε and temperature dissipation χθ estimates, as well as to a dependence of the mixing efficiency γ on the Richardson number or in some cases on regions of fossil turbulence. 相似文献
79.
Deville Diego Sanchez Gustavo Barahona Sergio Yamashiro Carmen Oré-Chávez Daniel Bazán Roger Quiroz Umino Tetsuya 《Ocean Science Journal》2020,55(1):33-48
Ocean Science Journal - We evaluated the influence of areas with dissimilar upwelling intensity along the Humboldt Current System on the morphological variation of the economically important sea... 相似文献
80.
John M. Livingston Vladimir N. Kapustin Beat Schmid Philip B. Russell Patricia K. Quinn Timothy S. Bates Philip A. Durkee Peter J. Smith Volker Freudenthaler Matthias Wiegner Dave S. Covert Santiago Gassó Dean Hegg Donald R. Collins Richard C. Flagan John H. Seinfeld Vito Vitale Claudio Tomasi 《Tellus. Series B, Chemical and physical meteorology》2000,52(2):594-619