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991.
Peter Van Oosterom Bart Maessen Wilko Quak 《International journal of geographical information science》2013,27(8):713-748
Geographical information systems are more and more based on a DBMS with spatial extensions, which is also the case for the system described in this paper. The design and implementation of a generic geographical query tool, a platform for querying multiple spatio-temporal data sets and associated thematic data, is presented. The system is designed to be generic, that is without one specific application in mind. It supports ad-hoc queries covering both the spatial and the thematic part of the data. The generic geographic query tool will be illustrated with spatial and thematic Cadastral data. Special attention will be given to the temporal aspects: a spatio-temporal data model will be described together with a set of views for easy querying. DBMS views play an important role in the architecture of the system: integration of models, aggregation of information, presentation of temporal data, and so on. The current production version of the geographic query tool within the Dutch Cadastre is based on GeoICT products with a relatively small market share (Ingres and GEO++). A new prototype version is being developed using mainstream Geo-ICT products (Oracle and MapInfo). First results and open issues with respect to this prototype are presented. 相似文献
992.
D. Van de Vlag B. Vasseur A. Stein R. Jeansoulin 《International journal of geographical information science》2013,27(10):1057-1072
An ontological approach in GIS serves as a framework for the conceptualization of processes in the real world. In this paper, we examine an application in coastal change in the Netherlands, whereby beaches are subject to artificial nourishment to offset the effect of severe erosion. The use of ontologies helps to define two scenarios: SI determined by the regulations from the Ministry for Public Works; SII grounded on the abilities from an existing spatial dataset. A comparison between SI and SII shows that 72.8% of the objects suitable and unsuitable for nourishment are correctly classified. A higher overlap is found in areas where actual beach nourishments were carried out. Inaccuracies in attributes influence the determination of the objects. A sensitivity analysis applied to altitude illustrates a significant increase of objects suitable for nourishment for both scenarios, when altitude is decreased within the lower limit of the root mean square error for the 95% confidence interval. Moreover, the sensitivity of altitude shows that artificial boundaries for beach nourishment objects are not reasonable and consequently should be treated as vague objects. 相似文献
993.
T. Neutens F. Witlox N. Van De Weghe P. H. De Maeyer 《International journal of geographical information science》2013,27(10):1061-1076
Constraint‐based models and models constructing accessibility measures mainly focus on single agents having only one available transport mode. However, numerous cases exist where multiple agents or groups of individuals with different available transport modes want to participate in a joint activity at a certain location. The aim of this paper is to provide new insights into representing and reasoning about feasible space–time opportunities for multiple agents. Relying on concepts of time geography, we propose a conceptual framework in order to determine interaction spaces for groups of individuals. Besides availability of means of transport and the locations of each individual, minimum activity duration and opening hours of opportunities are taken into account. The reasoning about space and time is visualized in three dimensions using a hybrid (CAD/GIS) system. 相似文献
994.
N. V. Chukanov G. Blass I. V. Pekov D. I. Belakovskiy K. V. Van R. K. Rastsvetaeva S. M. Aksenov 《Geology of Ore Deposits》2012,54(8):647-655
Non-metamict perrierite-(La) discovered in the Dellen pumice quarry, near Mendig, in the Eifel volcanic district, Rheinland-Pfalz, Germany has been approved as a new mineral species (IMA no. 2010-089). The mineral was found in the late assemblage of sanidine, phlogopite, pyrophanite, zirconolite, members of the jacobsite-magnetite series, fluorcalciopyrochlore, and zircon. Perrierite-(La) occurs as isolated prismatic crystals up to 0.5 × 1 mm in size within cavities in sanidinite. The new mineral is black with brown streak; it is brittle, with the Mohs hardness of 6 and distinct cleavage parallel to (001). The calculated density is 4.791 g/cm3. The IR spectrum does not contain absorption bands that correspond to H2O and OH groups. Perrierite-(La) is biaxial (-), α = 1.94(1), β = 2.020(15), γ = 2.040(15), 2V meas = 50(10)°, 2V calc = 51°. The chemical composition (electron microprobe, average of seven point analyses, the Fe2+/Fe3+ ratio determined from the X-ray structural data, wt %) is as follows: 3.26 CaO, 22.92 La2O3, 19.64 Ce2O3, 0.83 Pr2O2, 2.09 Nd2O3, 0.25 MgO, 2.25 MnO, 3.16 FeO, 5.28 Fe2O3, 2.59 Al2O3, 16.13 TiO2, 0.75 Nb2O5, and 20.06 SiO2, total is 99.21. The empirical formula is (La1.70Ce1.45Nd0.15Pr0.06Ca0.70)Σ4.06(Fe 0.53 2+ Mn0.38Mg0.08)Σ0.99(Ti2.44Fe 0.80 3+ Al0.62Nb0.07)Σ3.93Si4.04O22. The simplified formula is (La,Ce,Ca)4(Fe2+,Mn)(Ti,Fe3+,Al)4(Si2O7)2O8. The crystal structure was determined by a single crystal. Perrierite-(La) is monoclinic, space group P21/a, and the unit-cell dimensions are as follows: a =13.668(1), b = 5.6601(6), c = 11.743(1) Å, β = 113.64(1)°; V = 832.2(2) Å3, Z = 2. The strong reflections in the X-ray powder diffraction pattern are [d, Å (I, %) (hkl)]: 5.19 (40) (110), 3.53 (40) ( $\overline 3 $ 11), 2.96 (100) ( $\overline 3 $ 13, 311), 2.80 (50) (020), 2.14 (50) ( $\overline 4 $ 22, $\overline 3 $ 15, 313), 1.947 (50) (024, 223), 1.657 (40) ( $\overline 4 $ 07, $\overline 4 $ 33, 331). The holotype specimen of perrierite-(La) is deposited at the Fersman Mineralogical Museum, Russian Academy of Sciences, Moscow, Russia, with the registration number 4059/1. 相似文献
995.
Rina Argelia Andersson Philip Meyers Edward Hornibrook Peter Kuhry Carl‐Magnus Mörth 《第四纪科学杂志》2012,27(6):545-552
A peat deposit from the East European Russian Arctic, spanning nearly 10 000 years, was investigated to study soil organic matter degradation using analyses of bulk elemental and stable isotopic compositions and plant macrofossil remains. The peat accumulated initially in a wet fen that was transformed into a peat plateau bog following aggradation of permafrost in the late Holocene (~2500 cal a BP). Total organic carbon and total nitrogen (N) concentrations are higher in the fen peat than in the moss‐dominated bog peat layers. Layers in the sequence that have lower concentrations of total hydrogen (H) are associated with degraded vascular plant residues. C/N and H/C atomic ratios indicate better preservation of organic matter in peat material dominated by bryophytes as opposed to vascular plants. The presence of permafrost in the peat plateau stage and water‐saturated conditions at the bottom of the fen stage appear to lead to better preservation of organic plant material. δ15N values suggest N isotopic fractionation was driven primarily by microbial decomposition whereas differences in δ13C values appear to reflect mainly changes in plant assemblages. Positive shifts in both δ15N and δ13C values coincide with a local change to drier conditions as a result of the onset of permafrost and frost heave of the peat surface. This pattern suggests that permafrost aggradation not only resulted in changes in vegetation but also aerated the underlying fen peat, which enhanced microbial denitrification, causing the observed 15N‐enrichment. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
996.
Nick D. Bryan Liam Abrahamsen Nick Evans Peter Warwick Gunnar Buckau Liping Weng Willem H. Van Riemsdijk 《Applied Geochemistry》2012
Some recent developments made during the European Union 6th Framework Integrated Project FUNMIG in the understanding and prediction of behaviour in ternary systems of radionuclides, humic substances and mineral surfaces are described. These developments are placed in the context of the existing literature. The aim is to describe the current understanding of humic substance mediated radionuclide transport as it may be applied to calculations in support of Radiological Performance Assessment. Some improvements in experimental techniques that provide the raw data to calibrate metal ion binding models are explained. The various metal ion binding models that are available are described and contrasted, before the recent development of ternary system models, in particular the Ligand Charge Distribution model that can predict metal ion and humic substance behaviour in ternary systems. The kinetic effects in ternary systems are described along with the models that are used to describe them. Finally, the remaining challenges in making predictions of radionuclide transport for the Radiological Performance Assessment of radioactive waste repositories are discussed. 相似文献
997.
Most research on the Palestinian-Israeli conflict has focused on macro and meso-levels of abstraction by exploring national territorial and urban scales. This article, however, takes a more micro-level approach by investigating one specific public space in detail. It analyses the transformation and use of Dawar, the main public space of the city of Nablus, during the First (1987–1993) and Second (2000–2005) Intifadas. Public spaces in Palestinian cities have been transformed during the two Intifadas on both the physical and the socio-economic levels. Changing power relations affect the way public spaces are produced and regulated. Citizens, too, (re)produce public spaces through everyday practices, uses, and—in our case—explicit forms of resistance. The study proposes an analytical framework to look at public spaces as the result of power relations by combining the work of two French theorists, Michel Foucault and Henri Lefebvre. This framework is then applied to Dawar during the two Intifadas. 相似文献
998.
The ca 2.74 Ga Mopoke Member,Kylena Formation: a marine incursion into the northern Fortescue Group?
D. T. Flannery M. J. Van Kranendonk R. Mazumder M. r. Walter 《Australian Journal of Earth Sciences》2013,60(8):1095-1108
The northern part of the Fortescue Group consists of interbedded flood basalts and sedimentary rocks that were deposited on the southern margin of the Pilbara Craton, Western Australia, during one or more periods of continental rifting between ca 2.78 and ca 2.63 Ga. Well-preserved sedimentary intervals within the group have yielded stable carbon and sulfur isotope data that have been used to infer changes in geobiological processes in the Neoarchean. However, the Fortescue Group is notable for being a predominantly subaerial succession, and it remains unclear whether data obtained from these intervals should be interpreted in the context of deposition in marine environments, possibly recording changes in the global ocean/atmosphere system, or in local and restricted lacustrine settings. Here, we describe the sedimentology, stratigraphy, stromatolites and stable carbon isotope geochemistry of the ca 2.74 Ga Mopoke Member, Kylena Formation, the oldest stromatolitic horizon in the Fortescue Group. This unit differs in terms of internal stratigraphic relationships, sedimentology, carbonate mineralogy and stable isotope geochemistry when compared with intervals of probable lacustrine origin in the overlying Tumbiana and Maddina formations. In contrast, we suggest that parts of the Mopoke Member may have been deposited under open marine conditions, or alternatively, in a lacustrine environment characterised by differing water chemistry and basement topography. Stromatolitic microfabrics of the Mopoke Member are dominated by spar, dolospar and vertically aligned calcitic crusts, rather than the micritic microfabrics described from other Fortescue Group stromatolites. Mud-draped ripples are common sedimentary features in the Mopoke Member, suggesting a tidal influence. Mopoke Member δ13Ccarb values are generally slightly positive, but also include some significantly depleted values, which may relate to the reoxidation of 13C-depleted organic matter. δ13Corg values average –36.7‰, consistent with Neoarchean marine units reported from elsewhere, but significantly less 13C-depleted than values reported from overlying lacustrine intervals in the Fortescue Group. We conclude that some features of Fortescue Group datasets relevant to the field of geobiology may be facies dependent, and that more work focusing on the overall depositional environments of the Fortescue Group is needed in order to appropriately interpret geobiological data reported from that group. 相似文献
999.
Tectonic evolution of the Montagne Noire (french Massif Central): a model of extensional gneiss dome
AbstractThe tertonic interpretation of the Montagne Noire Gneiss Dome (southern French II Massif (Central) has been controversial for a long time. Several models have been proposed : diapirie uplift, wreneching and diapirism, compressive anticline, and metamorphie core complex. Evidence for extensional tectonics in the French Varisean Belt favours the latter interpretation. Strain and metamorphism patterns in the eastern part of the Montagne Noire result from two successive extensional deformations during Late Carboniferous to Permian times. The occurrence of a major detachment zone along the northern edge of the Montagne Noire Gneiss Dome as well the presence of sedimentary) basias to the north point to the asymmetry) of the Stephanian-Permian extensional system. We propose a new model of gneiss dome involving isostatie uprising and consecutive tectonic denudation of the duetile lower crust. This process results in asymmetrical extensional systems characterized by roll-under folding of the footwall and development of basins in the hangingwall as in the Montagne Noire. The model is finally discussed in comparison to previous interpretations. 相似文献
1000.
Influence of tectonics and neotectonics on the morphogenesis of the peak karst of Halong Bay,Vietnam
Pascal Fenart N. N. Cat Claude Drogue Doan Van Canh Sévenn Pistre 《Geodinamica Acta》2013,26(3-4):193-200
AbstractIn northeast Vietnam, the karst of Halong Bay is characterized by very active neotectonics. The directional distribution of fracturing of the calcareous rocks is characterized by the influence of two major fault zones: the Red River fault zone (N140) and the Tan-Lu fault zone (N050). Karst development was favoured by intense fracturing, according to these two major directions, and reactived during recent tectonics by a compressional regime with σ1 N070, followed by an extensional regimes with σ1 near to EW that led to significant vertical movement. These tectonics, coupled with intense erosion, led to genesis and evolution of the spectacular morphology of this peak karst. © Elsevier, Paris 相似文献