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61.
62.
Geographic masks are techniques used to protect privacy when publishing sensitive data in maps, but are not well adopted among researchers and may be difficult to execute for some GIS users. We developed a client‐side web application called MaskMy.XYZ that makes geographic masking easy to perform. It executes donut geomasking, a well‐known geographic mask, on thousands of points in seconds, and visualizes the original and masked point patterns in an integrated web map for visual comparison. MaskMy.XYZ also features metrics for both privacy protection and information loss, and allows users to rapidly and iteratively adjust masking parameters based on these metrics. The user interface was designed to prioritize usability, and clear documentation has been included to educate users about geographic masks, which is otherwise only found in niche literatures. By developing this application, we hope that geographic masks will be more widely adopted such that privacy is better protected in research. 相似文献
63.
Caroline Aubry-Wake Lauren D. Somers Haley Alcock Aspen M. Anderson Amin Azarkhish Samuel Bansah Nicole M. Bell Kelly Biagi Mariana Castaneda-Gonzalez Olivier Champagne Anna Chesnokova Devin Coone Tasha-Leigh J. Gauthier Uttam Ghimire Nathan Glas Dylan M. Hrach Oi Yin Lai Pierrick Lamontagne-Hallé Nicolas R. Leroux Laura Lyon Sohom Mandal Bouchra R. Nasri Nataša Popović Tracy E. Rankin Kabir Rasouli Alexis Robinson Palash Sanyal Nadine J. Shatilla Brandon Van Huizen Sophie Wilkinson Jessica Williamson Majid Zaremehrjardy 《水文研究》2020,34(8):2001-2006
64.
65.
Elevated dust deposition in Tierra del Fuego (Chile) resulting from Neoglacial Darwin Cordillera glacier fluctuations 
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下载免费PDF全文 66.
An adult male sperm whale (Physeter macrocephalus L.) which stranded in Hawke's Bay, New Zealand, was found to have seven erupted teeth in its upper jaw—six on the left side, and one on the right side. Each upper tooth lay in the side of the pit into which the corresponding lower tooth fitted, and two bore a groove consistent with contact with a lower tooth. 相似文献
67.
Graffiti is a ubiquitous feature of the urban landscape commonly perceived to be a symptom of disorder, deprivation, and violence. Broken windows theory asserts that it is also a cause. To examine this, we conduct a geographic correlation study of graffiti and violence using geographic information systems. A strong spatial covariation is observed, with spatially dependent residual clusters suggesting that the graffiti–violence relationship is context dependent and varied. Ferrell and Weide's spot theory provides a lens for situating hot spots and facilitating a more nuanced interrogation of graffiti and violence in several Vancouver neighborhoods. We advocate for situated spatial analyses of interpersonal violence to inform public health interventions and advance policymaking beyond the popular aesthetic symbolism of urban space. 相似文献
68.
In this paper, we investigate new ways of governing migrant populations in Germany brought forth by social policies on the local level of inner-city neighborhoods. In recent years, numerous initiatives on the local level have constituted the ‘migrant neighborhood’ as a site of governmental attention. One initiative that policymakers consider particularly innovative is the neighborhood mothers program in Berlin, a program that instructs migrant women as agents of neighborhood improvement and encourages them to establish peer-to-peer relations to other migrant women in order to pass on social norms. In the paper, we combine governmentality and intersectionality theory to critically examine the modes of behavior change promoted by the neighborhood mothers program and the political rationalities that are used to justify the governing of (and through) migrant women. We draw particular attention to the spatial dimensions of the neighborhood mothers program, to the ways in which it targets domestic and intimate spaces as sites of inspection and intervention and appoints migrant women as ‘door openers’ for entry of the state into the regulation of families and communities. 相似文献
69.
Mid-latitude pedestal craters on Mars offer crucial insights into the timing and extent of widespread ice-rich deposits during the Amazonian period. Our previous comprehensive analysis of pedestal craters strongly supports a climate-related formation mechanism, whereby pedestals result from impacts into ice-rich material at mid latitudes during periods of higher obliquity. The ice from this target deposit later sublimates due to obliquity changes, but is preserved beneath the protective cover of the armored pedestal. As such, the heights of pedestals act as a proxy for the thicknesses of the paleodeposits. In this analysis, our measurement of 2300 pedestal heights shows that although pedestals can reach up to ∼260 m in height, ∼82% are shorter than 60 m and only ∼2% are taller than 100 m. Mean pedestal heights are 48.0 m in the northern mid latitudes and 40.4 m in the southern mid latitudes, with the tallest pedestals located in Utopia Planitia, Acidalia Planitia and Malea Planum. We use these data in conjunction with prior climate model results to identify both regional and global trends regarding ice accumulation during obliquity excursions. Our data provide evidence for multiple episodes of emplacement and removal of the mid-latitude ice-rich deposit based on stratigraphic relationships between pedestal craters and the close proximity of pedestals with significantly different heights. 相似文献
70.
Jacqueline Malarkey Nadine Wittig D. Graham Pearson Jon P. Davidson 《Contributions to Mineralogy and Petrology》2011,162(2):289-302
Clinopyroxene is a major host for lithophile elements in the mantle lithosphere, and therefore it is critical whether we are
to understand the constraints that this mineral puts on mantle evolution and melt generation. This study presents a detailed
in situ trace element and Sr isotope study of clinopyroxene, amphibole and melt from two spinel lherzolites from the Middle
Atlas Mountains, Morocco. The results show that there is limited, but discernable, Sr isotopic variation between clinopyroxene
crystals within these xenoliths [87Sr/86Sr ranging from 0.703416 (±11 2SE) to 0.703681 (±12 2SE)]. Trace element patterns show similar interelement fractionation
with LREE enrichment, but there is a considerable range in terms of elemental concentration (e.g. over 100 ppm in Sr concentrations).
Observed modal clinopyroxene is far more abundant than that predicted from estimates of melt depletion. This along with isotope
and trace element variability found in these xenoliths supports a multistage metasomatic process in which clinopyroxene and
amphibole are recent secondary additions to the lithospheric mantle. Elemental systematics indicate that the metasomatic mineral
assemblage has most recently equilibrated with a carbonatitic melt prior to inclusion in the host basalt. The clinopyroxene
from this study is typical of global off-craton clinopyroxene in terms of Sr isotope composition, suggesting that the majority
of clinopyroxene in off-craton settings may have a recent metasomatic origin. These findings indicate that caution is required
when using peridotite xenoliths to estimate the degree of elemental enrichment in the subcontinental lithosphere. 相似文献