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Désirée Hilbring Anastasia Moumtzidou Jürgen Moßgraber Stefanos Vrochidis 《Transactions in GIS》2014,18(4):480-495
Many kinds of environmental data are nowadays publicly available, but spread over the web. This article discusses using the Sensor Observation Service (SOS) standard of the Open Geospatial Consortium (OGC) as a common interface for providing data from heterogeneous sources which can be integrated to a user tailored environmental information system. In order to allow for providing user‐tailored and problem‐specific information the adjusted SOS is augmented by a semantic layer which maps the environmental information to ontology concepts. The necessary information fusion from different domains and data types lead to several specific requirements for the SOS. Addressing these requirements we have implemented a SOS which still conforms to the OGC SOS 1.0.0 standard specification. The developed SOS has been integrated in a publicly available demonstrator of our personalized environmental information system. Additionally this article discusses future consequences for the SOS, caused by the recently published SOS 2.0 specification. 相似文献
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Aur��lien Bideaud Benoit Belier Alain Benoit Laurent Berg�� Philippe Camus Sophie Collin Louis Dumoulin Christian Hoffmann Stefanos Marnieros Alessandro Monfardini 《Experimental Astronomy》2011,32(2):179-191
Microbolometers are at present the most sensitive detectors for mm and sub-mm Astronomy. They are in use in most of the present instruments in that bandwidth. We have developed filled arrays of NbSi-based planar antenna coupled microbolometers. The fabrication details are given, together with characterization of the NbSi thermometers and optical results. The optical performances are potentially good for ground-based mm-wave astronomy applications, while the overall detectors performances are limited by low-frequency excess noise in the thermometric NbSi high-impedance sensors (Anderson insulator). 相似文献
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Lazoglou Georgia Anagnostopoulou Christina Koundouras Stefanos 《Theoretical and Applied Climatology》2018,133(1-2):551-567
Theoretical and Applied Climatology - Viticulture represents an important economic activity for Greek agriculture. Winegrapes are cultivated in many areas covering the whole Greek territory, due to... 相似文献
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Thomas Hainschwang Stefanos Karampelas Emmanuel Fritsch Franck Notari 《Mineralogy and Petrology》2013,107(3):393-413
The methods of luminescence spectroscopy and microscopy are widely used for the analysis of gem materials. This paper gives an overview of the most important applications of the analysis of laser and UV excited luminescence by spectroscopy and visually by microscopy with emphasis on diamond, and specifically natural type Ib diamond, little studied so far. Luminescence based techniques are paramount to the gemmological analysis of diamond, in order to determine whether it is natural, treated or synthetic. The great sensitivity of luminescence helps detect some emitting centres that are undetectable by any other analytical method. Hence, especially for diamond, luminescence is an enabling technology, as illustrated by its pioneering use of imagery for the separation of natural and synthetic diamond, and of spectroscopy for the detection of High Pressure–High Temperature treatment. For all other gemstones the applications are at the moment less numerous, but nevertheless they remain highly important. They provide quickly information on the identification of a gem material, and its treatment. Besides the study of broad band emissions caused by various colour centres, the typical PL-causing trace elements (amongst others) are chromium, manganese, uranium and rare earth elements. In pearls the study of broad band luminescence can be useful, and particularly the study of pink to red porphyrin luminescence in pearls from certain species such as Pinctada and Pteria and others can help identify the pearl-producing mollusc, or if a pearl has been dyed or not. Type Ib diamonds are representative of the importance and complexity of the analysis of luminescence by microscopy and spectroscopy. They show a wide range of sometimes very complex emissions that result in luminescence colours from green to yellow to orange or red. These emissions show generally very inhomogeneous distribution. They are caused by a range of defects, however only a few of them are well characterized. 相似文献
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Andriana Giannouli Stavros Kalaitzidis George Siavalas Adamantia Chatziapostolou Kimon Christanis Stefanos Papazisimou Cassiani Papanicolaou Antonis Foscolos 《International Journal of Coal Geology》2009,77(3-4):383-393
This study evaluates Greek peat and coal samples for applications in the agricultural/horticultural sector and assesses the suitability of a certain peat/coal either as soil conditioner or as raw material for manufacturing organic fertilizers.Twenty-six samples of different rank ranging from peat to subbituminous coal obtained from several Greek peat/coal deposits, were studied. The laboratory tests included: a) pH and electrical conductivity (EC) determinations, as well as proximate, ultimate and maceral analyses, in order to characterize the samples, b) major and trace element analyses of both the total and the easily exchangeable fractions (EEF), in order to assess the phytotoxicity effect, c) cation exchange capacity (CEC) determination in mixtures of the samples (5 wt.%) with a certain soil (95 wt.%), in order to evaluate the peat/coal impact, and d) the determination of the contents of humic substances (HS), as well as of carboxylic and phenolic groups.The majority of the samples reveal moderate to high ash yields (16–80 wt.%), a slightly acidic to neutral character and electrical conductivity ranging from 100–2500 μS/cm. Concerning the environmental impact of the sensitive trace elements, which might be leached, As, Mn, Ni and Sr show relatively strong mobilization in some samples, although severe impacts are not expected. The soil's CEC is generally improved, although it remains at moderate levels. The most interesting aspect is the humic acids content, which ranges between 9.6 and 52.2 wt.% on a dry basis, exceeding 25 wt.% for most of the samples. The obtained results enable an initial correlation among the different parameters and a rating of the samples according to their suitability for soil-amelioration agents. 相似文献
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Tudisco Erika Vitone Claudia Mondello Cristina Viggiani Gioacchino Athanasopoulos Stefanos Hall Stephen A. Cotecchia Federica 《Acta Geotechnica》2022,17(5):1585-1603
Acta Geotechnica - This paper reports the main results of an experimental study on the mechanics of intensely fissured natural clays, extending our previous studies on scaly clay from Santa Croce... 相似文献
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MPOKOS J.Panagiotis YIAKOULAKI D.Maria PAPAZAFEIRIOU Z.Agapi SGARDELIS Stefanos ALIFRAGIS Dimitrios PAPANIKOLAOU Konstantinos 《山地科学学报》2014,(6):1579-1592
Several abiotic and biotic factors were investigated as possible predictors of local species richness in two sub-alpine grasslands of Jenna and Belles Mountains in Northern Greece.For species richness modelling a hierarchical modelling framework based on generalized additive models was adopted.The two sub-alpine grasslands differed in aspect,altitude and soil parent material(volcanic origin,mostly trachyte,and andesite(TA) for Jenna and metamorphic rocks,mostly gneiss(G) for Belles).12 fenced squared plots,16 m2 each,were used per grassland,where soil properties,herbage production,species presence and cover of grasses,legumes and forbs were estimated.Mean herbage production was significantly affected by slope and altitude,soil K content and floristic composition as expressed by an ordination axis.Soil p H,floristic composition and average herbage production were significant predictors of forbs and total species richness.For the former,soil N content and for the latter the occurrence of Agrostis capillaris,were also included as significant terms in the predictive model.Thepredictors for grasses species richness were N content,having a positive effect,and average herbage production.In all cases higher species richness was predicted for intermediate values of average herbage production.Differential responses were found between forbs and grasses.The predictors of their species richness were different while for the case of the common predictor(N) the responses of the two groups were also different(grasses species numbers increase and forbs species numbers decreased with increasing N).Maximum species richness of grasses was observed at relatively low production levels while forbs species richness maximized at relatively high production levels. 相似文献
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Assessment of flood hazard based on natural and anthropogenic factors using analytic hierarchy process (AHP) 总被引:5,自引:3,他引:2
Flooding is the most common natural hazard in Greece, and most of low-lying urban centers are flood-prone areas. Assessment of flood hazard zones is a necessity for rational management of watersheds. In this study, the coupling of the analytical hierarchy process and geographical information systems were used, in order to assess flood hazard, based either on natural or on anthropogenic factors. The proposed method was applied on Kassandra Peninsula, in Northern Greece. The morphometric and hydrographic characteristics of the watersheds were calculated. Moreover, the natural flood genesis factors were examined, and subsequently, the anthropogenic interventions within stream beds were recorded. On the basis of the above elements, two flood hazard indexes were defined, separately for natural and anthropogenic factors. According to the results of these indexes, the watersheds of the study area were grouped into hazard classes. At the majority of watersheds, the derived hazard class was medium (according to the classification) due to natural factors and very high due to anthropogenic. The results were found to converge to historical data of flood events revealing the realistic representation of hazard on the relating flood hazard maps. 相似文献
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EDELWEISS Collaboration P. Di Stefano L. Berg B. Chambon M. Chapellier J. Chaumont G. Chardin P. Charvin M. De Jsus D. Drain L. Dumoulin P. Forget P. Garoche J. Gascon C. Goldbach D. L'Hte J. Mallet J. Mangin S. Marnieros L. Miramonti L. Mosca X-F. Navick G. Nollez P. Pari S. Pcourt E. Simon L. Stab J-P. Torre R. Tourbot D. Yvon 《Astroparticle Physics》2001,14(4):1425
The discrimination capabilities of a 70 g heat and ionization Ge bolometer are studied. This first prototype has been used by the EDELWEISS dark matter experiment, installed in the Laboratoire Souterrain de Modane, for direct detection of WIMPs. Gamma and neutron calibrations demonstrate that this type of detector is able to reject more than 99.6% of the background while retaining 95% of the signal, provided that the background events distribution is not biased towards the surface of the Ge crystal. However, the 1.17 kg day of data taken in a relatively important radioactive environment show an extra population slightly overlapping the signal. This background is likely due to interactions of low energy photons or electrons near the surface of the crystal, and is somewhat reduced by applying a higher charge-collecting inverse bias voltage (−6 V instead of −2 V) to the Ge diode. Despite this contamination, more than 98% of the background can be rejected while retaining 50% of the signal. This yields a conservative upper limit of 0.7 event day−1 kg−1 keVrecoil−1 at 90% confidence level in the 15–45 keV recoil energy interval; the present sensitivity appears to be limited by the fast ambient neutrons. Upgrades in progress on the installation are summarized. 相似文献
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