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411.
Akinlabi Emmanuel Maronga Björn Giometto Marco G. Li Dan 《Boundary-Layer Meteorology》2022,185(1):93-128
Boundary-Layer Meteorology - Large-eddy simulations (LES) are conducted to study the transport of momentum and passive scalar within and over a real urban canopy in the City of Boston, USA. This... 相似文献
412.
We report new petrological, phase equilibria modeling, and fluid inclusion data for pelitic and mafic granulites from Rundv?gshetta in the highest-grade region of the Neoproterozoic Lützow-Holm Complex(LHC),East Antarctica, and provide unequivocal evidence for fluid-rock interaction and high-temperature metasomatism in the presence of brine fluid. The studied locality is composed dominantly of well-foliated pelitic granulite(K-feldspar+quartz+sillimanite+garnet+ilmenite) with foliation-parallel bands and/or layers of mafic granulite(plagioclase+orthopyroxene+garnet+ilmenite+quartz+biotite). The boundary between the two lithologies is defined by thin(about 1 -20 cm in thick) garnet-rich layers with a common mineral assemblage of garnet+plagioclase+quartz+ilmenite+biotite ? orthopyroxene. Systematic increase of grossular and decrease of pyrope contents in garnet as well as decreasing Mg/(Fe+Mg) ratio of biotite from the pelitic granulite to garnet-rich rock and mafic granulite suggest that the garnet-rich layer was formed by metasomatic interaction between the two granulite lithologies. Phase equilibria modeling in the system NCKFMASHTO demonstrates that the metasomatism took place at 850 -860℃, which is slightly lower than the peak metamorphism of this region, and the modal abundance of garnet is the highest along the metapeliteemetabasite boundary(up to 40%), which is consistent with the field and thin section observations. The occurrence of brine(7.0 -10.9 wt.% Na Cleqfor ice melting or 25.1 -25.5 wt.% NaC leqfor hydrohalite melting) fluid inclusions as a primary phase trapped within plagioclase in the garnet-rich layer and the occurrence of Cl-rich biotite(Cl = 0.22 -0.60 wt.%) in the metasomatic rock compared to that in pelitic(0.15 -0.24 wt.%) and mafic(0.06-0.13 wt.%) granulites suggest infiltration of brine fluid could have given rise to the high-temperature metasomatism. The fluid might have been derived from external sources possibly related to the formation of major suture zones formed during the Gondwana amalgamation. 相似文献
413.
Aladejare Adeyemi Emman Alofe Emmanuel Damola Onifade Moshood Lawal Abiodun Ismail Ozoji Toochukwu Malachi Zhang Zong-Xian 《Geotechnical and Geological Engineering》2021,39(6):4427-4455
Geotechnical and Geological Engineering - Empirical relationships for estimating Uniaxial Compressive Strength (UCS) of rock from other rock properties are numerous in literature. This is because... 相似文献
414.
AbstractThis paper reports on the User-Centred Design and development of a web-mapping application from the Ocean Mapping Group (OMG) at the University of New Brunswick (UNB), to deliver ocean mapping data to ocean modellers. First, a work domain analysis was conducted to determine the required application functionality and content, consisting of an ocean modeller informal interview, a competitive analysis, and an online survey. Taking insight from the work domain analysis, a requirements document was prepared to support the development of the first application prototype. This prototype was then evaluated by eight target users, using a cognitive walkthrough and an online survey. The results from this evaluation led to a series of revisions to the functionality, content, and interface of the web-mapping application, establishing the revised prototype. The results showed a useful tool, end-user satisfaction, and stated a wide range of recommendations to enhance functionality for the next steps of the development. 相似文献
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Once completed, the Atacama Large Millimeter Array (ALMA) will be the most powerful (sub)millimeter interferometer in terms of sensitivity, spatial resolution and imaging. This paper presents the capabilities of ALMA applied to the observation of Centaurs and Trans-Neptunian Objects, and their possible output in terms of physical properties. Realistic simulations were performed to explore the performances of the different frequency bands and array configurations, and several projects are detailed along with their feasibility, their limitations and their possible targets. Determination of diameters and albedos via the radiometric method appears to be possible on ∼500 objects, while sampling of the thermal lightcurve to derive the bodies’ ellipticity could be performed at least 30 bodies that display a significant optical lightcurve. On a limited number of objects, the spatial resolution allows for direct measurement of the size or even surface mapping with a resolution down to 13 milliarcsec. Finally, ALMA could separate members of multiple systems with a separation power comparable to that of the HST. The overall performance of ALMA will make it an invaluable instrument to explore the outer Solar System, complementary to space-based telescopes and spacecrafts. 相似文献
417.
Emmanuel Skourtsos Daniel Vachard Alexandra Zambetakis-Lekkas Rossana Martini Louisette Zaninetti 《Comptes Rendus Geoscience》2002,334(12):925-931
Some olistolites reworked in a Tertiary flysch of Mount Parnon (Peloponnesus, Greece) exhibit a Late Permian assemblage, dominated by Paradunbarula (Shindella) shindensis, Hemigordiopsis cf. luquensis and Colaniella aff. minima. This association corresponds to the Late Wuchiapingian (=Late Dzhulfian), a substage whose algae and foraminifera are generally little known. Contemporaneous limestones crop out in the middle part of the Episkopi Formation in Hydra, but they are rather commonly reworked in Mesozoic and Cainozoic sequences. The palaeobiogeographical affinities shared by the foraminiferal markers of Greece, southeastern Pamir, and southern China, are very strong (up to the specific level), and are congruent with the Pangea B reconstructions. To cite this article: E. Skourtsos et al., C. R. Geoscience 334 (2002) 925–931. 相似文献
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420.
Application of Artificial Neural Networks to Complex Groundwater Management Problems 总被引:4,自引:0,他引:4
Coppola Emery Poulton Mary Charles Emmanuel Dustman John Szidarovszky Ferenc 《Natural Resources Research》2003,12(4):303-320
As water quantity and quality problems become increasingly severe, accurate prediction and effective management of scarcer water resources will become critical. In this paper, the successful application of artificial neural network (ANN) technology is described for three types of groundwater prediction and management problems. In the first example, an ANN was trained with simulation data from a physically based numerical model to predict head (groundwater elevation) at locations of interest under variable pumping and climate conditions. The ANN achieved a high degree of predictive accuracy, and its derived state-transition equations were embedded into a multiobjective optimization formulation and solved to generate a trade-off curve depicting water supply in relation to contamination risk. In the second and third examples, ANNs were developed with real-world hydrologic and climate data for different hydrogeologic environments. For the second problem, an ANN was developed using data collected for a 5-year, 8-month period to predict heads in a multilayered surficial and limestone aquifer system under variable pumping, state, and climate conditions. Using weekly stress periods, the ANN substantially outperformed a well-calibrated numerical flow model for the 71-day validation period, and provided insights into the effects of climate and pumping on water levels. For the third problem, an ANN was developed with data collected automatically over a 6-week period to predict hourly heads in 11 high-capacity public supply wells tapping a semiconfined bedrock aquifer and subject to large well-interference effects. Using hourly stress periods, the ANN accurately predicted heads for 24-hour periods in all public supply wells. These test cases demonstrate that the ANN technology can solve a variety of complex groundwater management problems and overcome many of the problems and limitations associated with traditional physically based flow models. 相似文献