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11.
In shipping, safety depends on the reliability of the technical and human components of the ship-system, although the marine environment itself may sometimes be so hostile as to give rise to accidents that are beyond technical and human control. The need for a continuous analysis of shipping accidents is dictated by the accumulated evidence for the predominance of the human factor and the ever-increasing pressure for further improvement on the safety record of shipping. In this context, the effectiveness of enforced regulations towards the promotion of safety policy in shipping is assessed and the debate and focus on this issue are maintained. 相似文献
12.
Maria V. Triantaphyllou Alexandra Gogou Margarita D. Dimiza Sofia Kostopoulou Constantine Parinos Grigoris Roussakis Maria Geraga Ioanna Bouloubassi Dominik Fleitmann Vassilis Zervakis Dimitris Velaoras Antonia Diamantopoulou Angeliki Sampatakaki Vassilis Lykousis 《Geo-Marine Letters》2016,36(1):51-66
13.
Michael Anastassiadis Georges Moraitis Dimitris Matsoukas 《Planetary and Space Science》1973,21(9):1581-1586
A method for the determination of electron densities up to 1000 km by using data from vertical sounding and Faraday rotation techniques is suggested. Electron density profiles and contours plotted following this method are compared with results obtained by Evans using the incoherent scatter technique. 相似文献
14.
Giuditta Marinaro Giuseppe Etiope Nadia Lo Bue Paolo Favali George Papatheodorou Dimitris Christodoulou Flavio Furlan Francesco Gasparoni George Ferentinos Michel Masson Jean-François Rolin 《Geo-Marine Letters》2006,26(5):297-302
A new seafloor observatory, the gas monitoring module (GMM), has been developed for continuous and long-term measurements of methane and hydrogen sulphide concentrations in seawater, integrated with temperature (T), pressure (P) and conductivity data at the seafloor. GMM was deployed in April 2004 within an active gas-bearing pockmark in the Gulf of Patras (Greece), at a water depth of 42 m. Through a submarine cable linked to an onshore station, it was possible to remotely check, via direct phone connection, GMM functioning and to receive data in near-real time. Recordings were carried out in two consecutive campaigns over the periods April–July 2004, and September 2004–January 2005, amounting to a combined dataset of ca. 6.5 months. This represents the first long-term monitoring ever done on gas leakage from pockmarks by means of CH4+H2S+T+P sensors. The results show frequent T and P drops associated with gas peaks, more than 60 events in 6.5 months, likely due to intermittent, pulsation-like seepage. Decreases in temperature in the order of 0.1–1°C (up to 1.7°C) below an ambient T of ca. 17°C (annual average) were associated with short-lived pulses (10–60 min) of increased CH4+H2S concentrations. This seepage “pulsation” can either be an active process driven by pressure build-up in the pockmark sediments, or a passive fluid release due to hydrostatic pressure drops induced by bottom currents cascading into the pockmark depression. Redundancy and comparison of data from different sensors were fundamental to interpret subtle proxy signals of temperature and pressure which would not be understood using only one sensor. 相似文献
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17.
Duncan Forgan Ken Rice Dimitris Stamatellos Anthony Whitworth 《Monthly notices of the Royal Astronomical Society》2009,394(2):882-891
A new means of incorporating radiative transfer into smoothed particle hydrodynamics (SPH) is introduced, which builds on the success of two previous methods – the polytropic cooling approximation as devised by Stamatellos et al. and flux-limited diffusion. This hybrid method preserves the strengths of its individual components, while removing the need for atmosphere matching or other boundary conditions to marry optically thick and optically thin regions. The code uses a non-trivial equation of state to calculate temperatures and opacities of SPH particles, which captures the effects of H2 dissociation, H0 ionization, He0 and He+ ionization, ice evaporation, dust sublimation, molecular absorption, bound-free and free–free transitions and electron scattering. The method is tested in several scenarios, including (i) the evolution of a 0.07 M⊙ protoplanetary disc surrounding a 0.5 M⊙ star; (ii) the collapse of a 1 M⊙ protostellar cloud and (iii) the thermal relaxation of temperature fluctuations in a static homogeneous sphere. 相似文献
18.
Dimitris?S.?KostopoulosEmail author Sevket?Sen George?D.?Koufos 《International Journal of Earth Sciences》2003,92(5):779-794
The late Miocene mammalian record in Samos Island, Greece, is extremely important for the Eurasian Neogene mammalian history and chronology. However, due to the mixed nature of old fossil collections and controversies on the stratigraphic position of fossil quarries, great confusion has arisen concerning the recognition of distinct faunal assemblages, their age(s) and biostratigraphic significance. This paper presents the magnetostratigraphy of the late Miocene continental deposits of the fossiliferous Mytilinii Basin, Samos Island, Greece. Old and new sites are stratigraphically controlled with accuracy and correlated with each other. The magnetostratigraphy of seven individual sections, covering the entire Mytilinii Formation, provides good correlation with the Geomagnetic Polarity Time Scale (GPTS). These results, as well as the relocation and precise litho- and magnetostratigraphic correlation of the old and new mammal localities, combined with new and reviewed paleontological data and thorough studying of the numerous radiometric dates, allowed us to define five biostratigraphic horizons. Their correlation with, and implications to the European Neogene mammal chronology ages and zones make up the following discussion and provides a modified determination of the middle Turolian (MN 12) boundaries.Abbreviations GPTS Geomagnetic Polarity Time Scale - IPGP Institute de Physic du Globe de Paris - MGL Musée Cantonal de Géologie, Lausanne - MNHA Museum of Natural History of the Aegean, Samos - BMNH Natural History Museum of London - Q quarries - Fm Formation 相似文献
19.
Dimitris Ballas 《Area》2004,36(2):146-163
How much does the 2001 census tell us about the changes in people's life in British cities and regions since 1991? This paper attempts to answer this question by telling the stories of two British northern cities: Leeds and Sheffield. In particular, the paper investigates and compares socio-economic change in these cities on the basis of actual 1991 and 2001 census data as well as estimated non-census data. A static spatial microsimulation model is used to combine the outputs of the 1991 and 2001 censuses of UK population with data from the British Household Panel Survey (BHPS) data. In particular, selected Small Area Statistics (SAS) tables from the 1991 and 2001 censuses are used as constraints in the spatial microsimulation modelling exercise, which aims to reweight BHPS household records so that they satisfy these constraints. The paper briefly discusses the change in these census variables across different localities of the two cities. It is then shown how the changes in these variables affect the simulation of non-census variables. Further, the microsimulation model is used to estimate the trends in income inequalities and child poverty between and within the two cities. Finally, the paper discusses the implication of the research findings for policy formulation. 相似文献
20.
Strong seismic events once again confirm the view that great destructive earthquakes are produced by the reactivation of pre-existing
faults although they have usually remained inactive for many, perhaps thousands of years. It is evident that such active seismogenic
zones, with little or no seismicity, have presumably been ignored in the determination of the region's seismic hazard.
At south Peloponnesus, Greece, is situated at Taygetos mountain. At its eastern front lies a large normal fault system, the
southern segment being the Sparta fault. This area has been characterized by low seismicity for the last 25 centuries. However,
during the 6th and 5th centuries B.C. several destructive earthquakes have been reported. That of 464 B.C., was the most destructive
and devastated the city of Sparta. Detailed morphotectonic observations of this area, suggest that the earthquake of 464 B.C.
could be related to the most recent reactivation of this fault.
The ground accelerations that would be produced by a future activation of the Sparta fault, were calculated, by applying a
method which takes into account information mainly from the seismotectonic parameters of the Sparta fault, the rupture pattern,
the properties of the propagation medium and the local ground conditions. Moreover, these results were compared with those
of other independent studies based mainly on the seismic data of the area. This method estimated greater expected values of
ground acceleration than those computed by the conventional seismic hazard methods. The highest values correspond to the activation
of the Sparta fault either in a unilateral rupture, which would start from the southernmost point of the fault, or in a circular
one. Furthermore, an increase is observed of the order of 50% in the ground acceleration values in unconsolidated soft ground
in relation to the corresponding values of hard ground.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献