Archambeau's Elastodynamical Source-Model Solution and Low-Frequency Spectral Peaks in the Far-Field Displacement Amplitude     

J. Arthur Snoke 《Geophysical Journal International》1976,44(1):27-44

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Role of container vessels in the introduction of exotic species     

Niimi AJ 《Marine pollution bulletin》2004,49(9-10):778-782

Ballast water exchange practices were monitored on 28 incoming container vessels at the Port of Montreal. Measurements on 15 vessels indicated 13 of 32 tanks had salinities of <30 per thousand. The 16 transits with a North Atlantic route visited 31 of 37 ports located on freshwater or near freshwater outflows. Ballast carried by this vessel type represents an important means for the introduction of species on a global scale because of its transit routes, dockside discharge and moving ballast between tanks. Container vessels represent about 15% of the world fleet, but account for 32% of all visits to global ports, and 46% of visits to the 25 largest ports. The 10 ports that handled the largest volumes of international cargo also included 8 that handled the most cargo containers. Large ports can receive over 100,000 visits by all vessel types annually, and serve as hubs for over 500 ports in 100 countries. Secondary transport of exotic species is also a concern because of frequent visits by regional vessels.  相似文献   

The effects of two benthic chamber stirring systems on the diffusive boundary layer,oxygen flux,and passive flow through model macrofauna burrows     

Arthur?P.?WebbEmail author  Bradley?D.?Eyre 《Estuaries and Coasts》2004,27(2):352-361

Diffusive boundary layers (DBL), sediment oxygen flux, and natural passive flow through model macrofauna burrows were compared in two benthic chambers: one with a conventional rotational stirrer and the other with a two-dimensional flow diffuser system. Oxygen microprobe profiles showed that at similar velocities the mean diffusive boundary layer (DBL) thickness induced by a conventional rotor stirrer (453±118 μm) was not significantly different to that produced by the diffuser system (403±53 μm). The rotor produced twice as much DBL spatial variability (coefficient of variation 27%) as the diffuser (CV 11%). Variability between the rotor system’s DBL transect replicates was also two times greater (average CV of 22%) compared to the diffuser (CV 14%). At equivalent stirring speeds over experimental sediments, mean O₂ consumption rates were also not significantly different between the two systems. The diffuser induced consistently greater (16–37%) passive Bernoullian flow through model macrofauna borrows irrespective of the position of inhalant-exhalent openings. The rotor stimulated anomalous burrow flow regimes over a greater area of the chamber floor (36%) compared to the diffuser (23%). Depending on vent orientation the rotor was shown to reverse (exhalent to inhalant) burrow flow regimes in the central 9% of the chamber floor. This artifact of radial pressure and velocity differentials may have severe implications for tube dwelling infauna that rely on unidirectional flow. The diffuser system more closely mimicked natural two-dimensional water flow over the sediment surface and structures therein and is likely to give more representative results when measuring benthic processes within incubation devices.  相似文献   

Conditional probabilistic estimates of 21st century greenhouse gas emissions based on the storylines of the IPCC-SRES scenarios     

Detlef P. van Vuuren  Bert de Vries  Arthur Beusen  Peter S.C. Heuberger 《Global Environmental Change》2008,18(4):635

The conditional probabilistic scenario analysis combines statistical methods of uncertainty analysis at parameter level with storylines which recognize the deep uncertainty that exists for several underlying trends. The model calculations indicate that cumulative 21st century emissions could range from 800 to 2500 GtC in the absence of climate policy. This range originates partly from the underlying storylines, and partly from the probabilistic analysis. Among the most important parameters contributing to the uncertainty range are uncertainty in income growth, population growth, parameters determining energy demand, oil resources and fuel preferences. The contribution of these factors is also scenario-dependent.  相似文献   

Dark Matter in Wide Triple Systems of Galaxies     

Valentin P. Dolgachev  Arthur D. Chernin 《Astrophysics and Space Science》1997,252(1-2):151-153

Numerical models for wide triplets of galaxies are developed, and a statistical estimate of the dark matter content in these systems is derived. In a typical system, the mass of dark matter proves to be (1.5 - 3) × 1012h-1 M.  相似文献   

A GENERALISED ANALYTICAL RELATIVE ORIENTATION PROCEDURE AND ITS APPLICATION TO APOLLO 14 CLOSE UP PHOTOGRAPHY OF THE LUNAR SURFACE     

D. W. G. Arthur 《The Photogrammetric Record》1972,7(40):442-453

Close up photographs of the lunar surface obtained by the Apollo 14 astronauts presented unusual problems in relative orientation caused by essentially different directions of the camera axes. The problem was resolved by dividing each large unknown rotation into two parts, one of which was a large known part and the other was a small unknown part. The method succeeds when the unknown rotation elements can be initially estimated to about 10°.  相似文献   

A Catalogue of British Fossil Vertebrata     

Arthur Smith Woodward  Charles Davies Sherborn 《Proceedings of the Geologists' Association. Geologists' Association》1889,11(5):I-II

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Excursion to Walton heath and Headley with special reference to the supposed Pliocene deposits: Saturday,June 11th, 1921     

George W. Young  Ernest Arthur Turner 《Proceedings of the Geologists' Association. Geologists' Association》1921,32(4):231-235

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Excursion to the North Downs in Kent: Saturday,July 17th, 1920     

Arthur L. Leach  M.J. Bassett 《Proceedings of the Geologists' Association. Geologists' Association》1921,32(1):36-IN1

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Further notes on the geology of Shooter's Hill,Kent     

Arthur L. Leach 《Proceedings of the Geologists' Association. Geologists' Association》1930,41(3):343-IN11

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