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41.
This paper is concerned with the structure and dynamics of modern retail facilities in Israel. It presents the first comprehensive
quantitative study of the recent trends in Israeli retail. On the basis of an unique database that includes sizes and locations
of retailers for a number of years, we test and challenge some of the traditional theories, as well as the latest approaches
to the analysis of urban systems. Recent approaches view cities as self-organizing systems and utilize complexity theory and
concepts of order. In the case of Israeli retail application of alternate methods of analysis suggests that the conventional
regularities such as rank-size rule, as is implied by the central place theory or the more general power law do not hold.
The findings reveal that the sizes of modern retailers display an exponential distribution, consistent across time and scale.
This signifies a presence of stable regularity in the structure of retail sizes. Exponential distribution of the retail sizes
is shown to reflect a lack of interdependence between the existing and the planned retail facilities. The issue of order versus
randomness and self-organization in the size distribution of retailers remains debatable and requires further development
of tools and universal criteria for analyzing complex systems. 相似文献
42.
43.
Multi‐scale constraints of sediment source to sink systems in frontier basins: a forward stratigraphic modelling case study of the Levant region
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Nicolas Hawie Remy Deschamps Didier Granjeon Fadi H. Nader Christian Gorini Carla Müller Lucien Montadert François Baudin 《Basin Research》2017,29(Z1):418-445
Recent scientific work has highlighted the presence of an up to 12 km thick Cenozoic siliclastic and carbonate infill in the Levant Basin. Since the Late Eocene, several regional geodynamic events affecting Afro‐Arabia and Eurasia (collision and strike slip deformation) induced marginal uplifts. The initiation of local and long‐lived regional drainage systems in the Oligo‐Miocene period (e.g., Lebanon, Arabia and Nile) provoked a change in the depositional pattern along the Levant region from carbonate‐dominated to mixed clastic‐rich systems. Herein, we explore the importance of multi‐scale constraints (i.e., seismic, well and field data) in the quantification of subsidence history, sediment transport and deposition of a Middle to Upper Miocene “multi‐source” to sink system along the northern Levant frontier region. Through a comprehensive 4D forward stratigraphic modelling workflow, we suggest that the contribution to basin infill is split between proximal and more distal clastic sources as well as in situ carbonate and hemipelagic deposition. The results show that single‐source scenarios could not reasonably satisfy the basin‐scale constraints. The worldwide application of such new multi‐disciplinary workflows in frontier regions highlights the additional data constraints that are needed to de‐risk highly uncertain geological models in the hydrocarbon exploration phase. 相似文献
44.
Lucien Jeanmaire Michel Masson Francois Patti Pierre Germain Liliane Cappellini 《Marine pollution bulletin》1981,12(1):29-32
Analyses for 99Tc in some marine biological samples taken near the outlet of the low level radioactive effluent pipeline of the nuclear reprocessing plant of La Hague, France, gave positive results. From 500 to 3500 pCi kg?1 wet weight of 99Tc were observed in brown algae; Fucus sp. appeared to be a good indicator of this long-lived radionuclide in a marine environment. 相似文献
45.
Jean-Yves Boisson Lucien Bertrand Jean-François Heitz Yann Golvan 《Hydrogeology Journal》2001,9(1):108-123
In the context of a research and development program on waste disposal, an experimental site (Tournemire tunnel, Aveyron,
France) was selected by the French Institute for Nuclear Protection and Safety (IPSN) in order to undertake studies on potential
fluid flow at different scales of space and time within a 250-m-thick argillaceous formation. The argillite has a low natural
water content (~3–5%) and very low radii access porosity. Diffusion (tritiated water) coefficients (1×10–12 to 2×10–11 m2/s) and hydraulic conductivities derived from different types of laboratory tests (10–14 to 10–13 m/s) are characteristics of a very low-permeable rock. In situ hydraulic tests (including long-term hydraulic-head measurements)
were used to obtain values for hydraulic head and hydraulic conductivity at a scale of 1–10 m (10–13 to 10–11 m/s). Despite uncertainties on these data (due to a scale factor, presence of fissures, and possible artefacts due to hydro-chemo-mechanical
coupling), it is expected that fluid flow is essentially governed by diffusion processes. Identification of possible natural
flows at larger scales of time and space was investigated using natural isotopic tracers from interstitial fluids. Modelling,
based on the deuterium profile along the clay formation and assuming pure diffusion processes, provides estimations of possible
flow times. However, lack of knowledge concerning the past geological evolution of the site and the possible role of a fracture
network do not permit reduction of uncertainties on these estimations at this stage.
Electronic Publication 相似文献
46.
Lucien Brush 《Coastal Engineering》1986,10(4)
47.
Lucien Leclaire Yannis Bassias Micheline Denis-Clocchiatti Hugh Davies Isabelle Gautier Bernard Gensous Pierre-Jean Giannesini Philippe Patriat Jacques Segoufin Michel Tesson Jacques Wannesson 《Geo-Marine Letters》1987,7(4):169-176
Geological samples from the southern Kerguelen Plateau include Lower Cretaceous basalt and lava breccia, probable Lower Cretaceous conglomerate and shelf limestone, Upper Cretaceous chert with dolomite, Upper Cretaceous-Eocene ooze, and Tertiary conglomerate. Neogene sediments are only a few hundred m thick, and include foraminiferal and diatomaceous ooze, and ice-rafted debris. In conjunction with seismic reflection profiles, the samples indicate Early Cretaceous near-shore volcanism, followed by erosion, sedimentation, and subsidence through Cretaceous; arching of the plateau at the end of Cretaceous; subsidence through Paleogene; widespread emergence in mid-Tertiary; and slow subsidence through Neogene. 相似文献
48.
W.Q. Limond F. Gray G. Grau J.P. Fail L. Montadert Ph. Patriat 《Earth and Planetary Science Letters》1974,23(3):357-368
This paper describes a series of two ship refraction experiments carried out in the Bay of Biscay in May 1970 to determine the crustal structure to the southeast of Gascony sea mount. The results show that the seismic structure is similar to that found on Line B further to the northwest, but that the mantle is deeper. The structure is oceanic showing that it is unlikely that this area of the Bay of Biscay has been formed by downfaulting of continental crust. 相似文献
49.
Andreas Krein Holger Klinck Michael Eiden Wolfhard Symader Reinhard Bierl Lucien Hoffmann Laurent Pfister 《地球表面变化过程与地形》2008,33(1):152-163
This article deals with the following two questions. Are acoustic measurements in running waters appropriate for a highly resolved investigation of the bedload transport? Which characterizations of the bedload regarding mass and shape are possible via the acoustic signals? The signals were recorded by means of data recorders (Tascam Inc. DAP1 Portable Data Recorder) and hydrophones (International Transducer Corp. ITC‐4001 A). The ITC‐4001 is a shallow water omnidirectional transducer containing a flexural disc transducer utilizing Channelite‐5400 ceramics mounted in a rugged corrosion‐resistant housing. These hydrophones were screwed onto the bottom side of stainless steel plates, serving as a contact surface for the bedload in motion above them. After more than 100 series of tests in the laboratory, which indicated the basic relations between the dimension, shape and weight of the bedload and the resulting signal, field tests of the measuring system were conducted. By artificially produced flood waves in the small brooks Riverisbach, Olewiger Bach and by a winter flood wave in the River Moselle, it is possible to elaborate similar structures of the signal course of the bedload movement. The highest transport rates can be observed at the beginning of the increasing limbs and behind the peaks of the waves. At the beginning of the waves, the increasing transport power of the water and the loose material can be considered as the cause for this result. The high stream velocity behind the wave peaks explains the increase in the bedload transport so that material from the channel beds is unfastened and will be mobilized. The characterization of the bedload regarding the shape and mass is still limited regarding the field measurements and could be solved only for homogeneous grain sizes and single stones under laboratory conditions. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
50.
The daily solar radio flux values at 9400, 3750, 2000 and 1000 MHz and at 2800 MHz observed since 1957 at Toyokawa and Ottawa, respectively, have been used to provide new information on the solar radio fluxes as indices of solar activity. After an examination of the yearly mean values at each frequency, another investigation based on mean ratios during periods of 18 or 6 months indicates that a close connection is observed between the radio fluxes in the cm region and that anomalies related to calibration problems can be detected. The regression analysis of the daily values of the fluxes during at least 25 years and a special test on the sensitivity may provide final information on the stability of the data with respect to time and solar activity. The method is capable of detecting long-term trends corresponding to instrumental drifts. Such information is essential to our understanding of anomalies detected in the observations of u.v. and X-ray irradiances. However, such a method is based on a linear relationship. When a quadratic form, as it is observed in the decimeter region, is adopted, the effect of the various levels of activity in a solar cycle must be considered. 相似文献