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21.
Oleg Malkov Mikhail Sachkov Boris Shustov Pavel Kaigorodov Francisco Javier Yáñez Ana Ines Gómez de Castro 《Astrophysics and Space Science》2011,335(1):323-327
We present scientific program construction principles and a time allocation scheme developed for the World Space Observatory—Ultraviolet
(WSO-UV) mission, which is an international space observatory for observation in UV spectral range 100–300 nm. The WSO-UV
consists of a 1.7 m aperture telescope with instrumentation designed to carry out high resolution spectroscopy, long-slit
low resolution spectroscopy and direct sky imaging. The WSO-UV Ground Segment is under development by Spain and Russia. They
will coordinate the Mission and Science Operations and provide the satellite tracking stations for the project. 相似文献
22.
Human effects and environment impacts associated with nanoparticles generated from road traffic have recently attracted wide attention.Knowledge of the influencing variables on both number and mass of nanoparticles,sources,characteristics and limitations of advanced commercially accessible instruments for monitoring nanoparticles,are still scarce and not sufficient to make regulatory decision on solid particles smaller than 23 nm(SPN<23 nm).Given the harmful effects of nanoparticles on human health(i.e.visibility impairment,cardiac-rhythm disturbance,heart attacks,premature death,etc.),their control and assessment seem to be an absolute priority.In this overview,we classify and analyze the existing knowledge of nanoparticles in road traffic atmosphere,recent progress,and emerging priorities in research related to these topics.The major aspects of ongoing research in this field,and a brief discussion of the main sources of atmosphere nanoparticles are presented.The subsequent section focuses on the influencing parameters of nanoparticles including climate conditions,height above the road surface and distance between source(road traffic)and sampling site.The next section provides a comprehensive summary on sampling measurement methodologies and instrumental techniques.We also review the health and environment implications associated with particle exposure.Finally,an evaluation of the state of research related to nanoparticles together with highlights for future research activities are also presented. 相似文献
23.
Stefan Schöbel Kamal K Sharma Thorsten Hörbrand Theresa Böhm Ines Donhauser Helga de Wall 《Journal of Earth System Science》2017,126(6):90
The Neoproterozoic Sindreth Basin, NW India, and its surrounding area represent a half graben structure situated between the undeformed Malani Igneous Suite (MIS) in the west and a corridor of coeval Cryogenian ductile deformation, anatexis and granite intrusion in the east. The main lithologies observed in the basin are conglomerate, fanglomerate, debris flow and lake deposits derived from a nearby continental provenance, intercalated with concurrent mafic and felsic lava flows. Based on geological traverses across the strike of the basin, we propose a three-fold classification comprising Lower Clastic Unit and an Upper Clastic Unit and a Bimodal (basalt–rhyolite) Volcanic Unit separating the two. Tilting due to basin inversion and faulting has been observed; however, the rocks are unmetamorphosed and show undisturbed primary sedimentary features. The stratigraphic record of the basin is characteristic for deposition and magmatism in a fault-related continental setting. Implications of the findings have been discussed in the context of Neoproterozoic crustal dynamics in NW India. This study provides conclusive evidence for a continental setting for Sindreth Basin evolution and contests the recent models of active subduction setting (either back-arc basin or accretionary sediments over a subduction zone). 相似文献
24.
I. Alberico P. Petrosino G. Maglione L. Bruno F. S. Capaldo A. Dal Piaz L. Lirer S. Mazzola 《Natural Hazards》2012,64(2):1823-1854
Over the past few decades, intense urban expansion has occurred over the Campi Flegrei territorial system without considering the volcanic risk. In this active volcanic area, where a short period evacuation could be necessary, the emergency management cannot be based solely on hazard-related information. The territorial and social features must also be considered. In this framework, the main purpose of this research is to point out the seriousness of the present setting of the Campi Flegrei territorial system in case an evacuation is necessary. Following the concept of regional evacuation, the zone to be involved in emergency planning was identified as the whole of the area threatened by the volcanic events of the past 10?ka. Inside this area the spatial relation between the resident distribution and the outflows of roads, railway stations and harbours, to facilitate evacuation, was investigated. A spatial relational GIS-based procedure was used to draw the territorial system vulnerability map, depicting the zones with different capabilities to support the evacuation of residents in case of volcanic activity. Based on the concept that people could leave the dangerous area by the means of transport supplied by Civil Protection, and using the threshold value of over-crowding of 0.70 people/m2, we identified the collection areas for residents to be immediately evacuated in case of volcanic unrest, and five macrozones displaying different capabilities to cope with an emergency phase. 相似文献
25.
Integrated water resources management (IWRM) forms the widely accepted ecosystem approach to managing water and its related
resources in a sustainable way. Nevertheless, its implementation is still lagging behind, especially in developing and transition
countries which are often short of essential resources and face complex political dynamics. IWRM often requires a fundamental
realignment of governance structures. This may lead to problems of fit and institutional interplay as particular challenges
of multi-level governance. Against this background, a case study of Mongolia was carried out, a transition country suffering
from extreme climatic conditions and increasing depletion of its resources. While an attempt to introduce IWRM exists on paper,
it is less clear how it will be made politically and institutionally applicable. A document review and stakeholder interviews
were carried out to understand the progress and problems of introducing IWRM in Mongolia in the face of its transition and
decentralisation process. Problems of fit and interplay—which are in part results of the transformation—were identified, as
well as the approaches for their solution. Attempts are underway to overcome problems of fit such as the establishment of
river basin councils which are presently facing the challenges concerning their room for manoeuvre. Problems of interplay
arise when it comes to the cooperation and coordination of numerous water-related organisations which often lead to inconsistent
water governance. 相似文献
26.
27.
A multidisciplinary analysis of intraplate volcanic complexes interbedded with shallow and deeper marine sediments of a Late Miocene carbonate platform (Iblean Plateau, Sicily) has allowed a detailed paleo-environmental reconstruction. Our approach includes sedimentology, physical volcanology, stratigraphy, geochemistry/mineralogy, paleontology and 40Ar/39Ar dating. Four volcanic complexes are distinguished from each other. Two comprise an eastern shallow water platform (diatreme field and Carlentini complex) and two a western deeper water environment representing a seamount belt on the carbonate ramp (Valle Guffari seamount and Mineo complex). The late Miocene volcanism was not time-equivalent: episodic eruptions took place from the Late Tortonian (ca. 9.38 Ma at Mt. Carrubba) to Early Messinian (ca. 6.46 Ma at Valle Guffari). Explosive volcanism of the diatreme field may be related geodynamically to the period of periodic sea-level oscillations at the onset of the Messinian Salinity Crisis. Marine diatomites preserved in the crater areas of two diatremes are the only remnants of Early Messinian diatomites in the eastern Iblean Mountains. 相似文献
28.
Nazzareno Diodato Massimo Fagnano Ines Alberico Giovanni Battista Chirico 《Natural Hazards》2011,58(1):445-457
Evaluation of soil erodibility is an important task for Mediterranean lands, in which fertility and crop yield are significantly
affected by soil erosion. The soil physicochemical parameters affecting soil erodibility are highly variable in space and,
as for many other environmental variables, sample measurements are generally not enough for assessing its spatial variability
with an acceptable level of uncertainty at the scales of practical interest. This study illustrates the procedure applied
for estimating the pattern of soil erodibility across the Sele Basin (Southern Italy), where soil properties have been measured
on a limited number of sparse samples. Sampled data were integrated with other sparse data estimated by local regression functions,
which relate soil erodibility to auxiliary variables, such as terrain attributes and land system class memberships. Sampled
and estimated data were merged in a composed data set to assess the spatial pattern of soil erodibility by ordinary kriging.
The proposed approach offers effective spatial predictions, and it is exportable to regions where financial costs for soil
sampling are not feasible. 相似文献
29.
Extraction of information content from stochastic disaggregation and bias corrected downscaled precipitation variables for crop simulation 总被引:3,自引:3,他引:0
Ashok K. Mishra Amor V. M. Ines Vijay P. Singh James W. Hansen 《Stochastic Environmental Research and Risk Assessment (SERRA)》2013,27(2):449-457
We applied a simple statistical downscaling procedure for transforming daily global climate model (GCM) rainfall to the scale of an agricultural experimental station in Katumani, Kenya. The transformation made was two-fold. First, we corrected the rainfall frequency bias of the climate model by truncating its daily rainfall cumulative distribution into the station’s distribution based on a prescribed observed wet-day threshold. Then, we corrected the climate model rainfall intensity bias by mapping its truncated rainfall distribution into the station’s truncated distribution. Further improvements were made to the bias corrected GCM rainfall by linking it with a stochastic disaggregation scheme to correct the time structure problem inherent with daily GCM rainfall. Results of the simple and hybridized GCM downscaled precipitation variables (total, probability of occurrence, intensity and dry spell length) were linked with a crop model for a more objective evaluation of their performance using a non-linear measure based on mutual information based on entropy. This study is useful for the identification of both suitable downscaling technique as well as the effective precipitation variables for forecasting crop yields using GCM’s outputs which can be useful for addressing food security problems beforehand in critical basins around the world. 相似文献
30.
D. D. Insinga P. Petrosino I. Alberico G. J. de Lange C. Lubritto F. Molisso M. Sacchi R. Sulpizio J. Wu F. Lirer 《第四纪科学杂志》2020,35(1-2):213-231
Five cores from the southern Tyrrhenian and Ionian seas were studied for their tephra and cryptotephra content in the 4.4–2.0 ka time interval. The chronological framework for each core was obtained by accelerator mass spectrometry 14C dating, the occurrence of distinct marker tephra and stratigraphic correlation with adjacent records. Tephrochronology allowed us to correlate the analyzed deposits with tephra markers associated with Somma-Vesuvius (79 ad ), Ischia Island (Cretaio), Mt Etna (FG, FL and FS) and Campi Flegrei (Astroni-Agnano Monte Spina) events. For the first time in the marine setting, a large single glass data set is provided for the Late Holocene Etnean marker beds including the FS tephra (ca. 4.3 ka). Moreover, unknown deposits from Lipari (ca. 2.2–2.0 ka) and Vulcano (3.6–3.3 ka) are also recognized at more distal sites than previously reported. These results contribute to improve the high-resolution tephrostratigraphic framework of the central Mediterranean Sea. They also provide new insights into the chemical composition and dispersal pattern of tephras that can be used as inter-archive tools for regional and ‘local’ stratigraphic correlations and for addressing paleoclimate research. 相似文献