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151.
Mormone Angela Ghiara Maria Rosaria Balassone Giuseppina Piochi Monica Lonis Roberto Rossi Manuela 《Mineralogy and Petrology》2018,112(6):767-788
Mineralogy and Petrology - The island of Sardinia (Italy) presents some of the most interesting zeolite ores in Europe, most of which are associated with old pyroclastic deposits. In particular,... 相似文献
152.
Chanelle Wheeler-Jones Monica Seini Georgette Leah Burns 《The Australian geographer》2015,46(2):165-181
Recent neo-liberal policy frameworks in Australia advocate economic development opportunities for Aboriginal Australians as a viable strategy to redress the marginalisation and social disadvantage that appear to characterise many Aboriginal communities. In New South Wales (NSW), Aboriginal peoples are currently negotiating with industry for the chance to participate in coal seam gas (CSG) development opportunities. Based upon research focusing on CSG development in the Northern NSW region, this paper argues that certain constructions of Aboriginality inhibit successful Aboriginal engagement with the economic opportunities provided by CSG. This paper illuminates the role of the media in facilitating dominant discourse about Aboriginality and the implications of those constructions for Aboriginal engagement with the mainstream economy. Findings demonstrate that the media are complicit in constructing Aboriginal peoples in a way that could prejudice their attempts to engage in economic opportunities that do not align with the dominant constructions of Aboriginality. 相似文献
153.
Monica Wachowicz Tianyu Liu 《International journal of geographical information science》2016,30(9):1806-1831
ABSTRACTCurrently the increase in the variety and volume of data sources is demanding new data analytical workflows for exploring them concurrently, especially if the goal is to detect spatial outliers. In this paper, we propose a data analytical workflow for exploring Call Detail Records in conjunction with geotagged tweets. The aim was to investigate how massive data point observations can be analyzed to detect spatial outliers in collective mobility patterns that are coupled with social ties. This workflow consists of analytical tasks that are developed based on the a-priori assumption of two isometric spaces where Natural Language Processing techniques are used to find spatial clusters from geotagged tweets in a Social Space which are later used to aggregate the Call Detail Records generated by antennas located in the Mobility Space. The dynamic weighted centroids that are given by the mean location of the number of calls per hour of all antennas that belong to a particular cluster are used to compute Standard Deviation Ellipses. The longer the period of time a weighted centroid stays outside of the 99.7% probability region of an ellipse, the highest the likelihood that they are spatial outliers. The workflow was implemented for the city of Dakar in Senegal. The results indicate that the further the hourly weighted centroids are skewed from the normal mean of an ellipse, the stronger the influence of a cluster is in finding spatial outliers. Furthermore, the longer the period of time the outliers stays outside of the 99.7% probability region of an ellipse, the highest the likelihood that the outliers are genuine and can be associated to extraordinary events such as natural disasters and national holidays. 相似文献
154.
Covadonga Brime Maria Cristina Perri Monica Pondrelli Claudia Spalletta Corrado Venturini 《International Journal of Earth Sciences》2008,97(6):1213-1229
Thermal evolution of the Palaeozoic–Triassic sequences of the Carnic Alps has been characterized by b cell dimension and Kübler Index (illite “crystallinity”) of K-white micas (KI), árkai Index (AI) of chlorites, clay mineral
assemblages and conodont Colour Alteration Index (CAI). Data indicate at least two metamorphic events, Variscan and Alpine.
In the older event high anchizonal conditions predominated although epizonal conditions were reached over wide areas. It was
characterized by low-intermediate pressure facies. The thermal peak was mainly due to an extensional regime during the Bashkirian.
A younger thermal overprint generated by Alpine orogeny was of lower grade, reaching high diagenetic–anchizonal conditions
characterized by high-pressure facies. Inverted metamorphic patterns are associated with middle to late Miocene thrusting.
Hydrothermal alteration in the northern part of the region can be linked with emplacement of Oligocene plutons and high heat
flow along the Periadratic lineament.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
155.
Erik O. D. Sevre Monica D. Christiansen Matt Broten Shuo M. Wang David A. Yuen 《Visual Geosciences》2008,13(1):125-132
The Sony PlayStation 3 (PS3) offers the computational power of a parallel processor at low cost, which makes it a great starter
unit for development in parallel programming. To explore the capabilities of the unit, we took a simple ray tracing program
and extended it to render triangulated height field data across the PS3’s 6 synergistic processing units (SPUs). We also implemented
the heat averaging equation as a precursor to CFD analysis on the PS3. In our studies, we found the Cell engine in the PS3
to be a powerful machine, however great care must be taken while developing because its unique platform calls for many levels
of optimization to ensure efficiency.
For insight on early work done on modern stream computing and GPU processing look up the Merrimac project and Pat Hanrahan. 相似文献
156.
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158.
ABSTRACTThe present study proposes reliability-based approach for assessing the performance of shallow foundation placed in the vicinity of an existing buried flexible pipe or utility tunnel. Performance function for the reliability analysis is defined in terms of % bearing capacity loss in the load carrying capacity of the shallow foundation due to the presence of buried flexible pipe or utility tunnel, and, allowable bearing capacity loss in load carrying capacity that can be tolerated. For the reliability analysis, an explicit functional relationship between input variables, such as geotechnical parameters of in situ soil as well as material properties of pipe, and, output response, i.e. % bearing capacity loss in load carrying capacity of foundation soil is needed. Using concept of response surface methodology (RSM) combined with the results of the numerical analysis; such an explicit functional relationship is easily established. Thereafter, reliability analysis can be performed, conveniently, using standard First Order Second Moment (FOSM) approach and performance of the foundation soil system with buried flexible pipe, present in the vicinity, can be assessed in terms of an index, popularly known as ‘reliability index (β)’. 相似文献
159.
Luca Paolino Monica Sebillo Genoveffa Tortora Giuliana Vitiello 《Transactions in GIS》2010,14(6):731-753
The integrated management of heterogeneous spatial data, such as continuous fields and discrete data, is an important issue for the Geographic Information (GI) community. Indeed, GI users are forced to navigate among and operate with several tools in order to solve their spatial problems, due to the lack of systems capable of integrating different components, each meant to provide a specific solution. The aim of this article is to propose an OpenGeospatial‐compliant solution which supports expert users in handling problems involving heterogeneous data by means of a seamless approach. A class hierarchy modeling spatial discrete objects, continuous data, relationships, and operations, is described, whereby data are organized in agreement with the binary representation. A running example is illustrated to support readers' understanding of the proposed solution. Finally, some guidelines about an implementation modality are given, to demonstrate the applicability of the proposal to an existing DBMS. 相似文献
160.
Steady flow in a convoluted channel is studied via Particle Tracking Velocimetry. The channel is constructed from a sequence of closed parallel cylindrical tubes welded together in plane which are then sliced down the lateral mid-plane and the lower complex is laterally shifted relative to the upper complex. Flow is induced in the lateral direction normal to the axis of the tubes. The a-time, Ta, finite-size Lyapunov exponent, λa, and the real-space self- and distinct-part of the intermediate scattering functions, Gs and Gd, and the pair density function, Gp, are computed from the data. Particle trajectories, velocity maps and streamlines show the channel has two prominent recirculation zones and a main flow region. The first passage time probability density function of tagged particles past a plane transverse to the mean flow illustrates how particles are delayed by recirculation zones. The delay caused by fluid element folding is manifested in single particle statistics such as the first passage time and the slowing increase in horizontal evolution of Gs. Gp describes initial particle distribution and allows areas in the flow domain trapping particles to be identified and visualized. Gd shows the evolution of the average separation of pairs of particles and when examined in a recirculation zone, it evolves little because of fluid element rotation. λa gives information on what transpires at a fixed scale and provides an estimate of the rate at which particles initially separated by a distance x separate to a distance ax as opposed to Gd which allows one to view changes over time. At small separations, λ1.3 approaches a constant and for intermediate separations it scales as x−0.8. 相似文献