A Review of: “Urban and Regional Technology Planning: Planning Practice in the Global Knowledge Economy”     

Dorothy Ives Dewey 《The Professional geographer》2013,65(1):149-151

Haiti and other developing countries have increasingly turned to emigrant remittances as a potential source of development capital. There is a vigorous debate in the development community about the impacts of remittances, however, with concerns about dependence challenging the optimism about a potential new development engine. Based on interviews with forty-two remittance recipients in Haiti and forty-five corresponding senders in New York State, we find that the remittance economy in Haiti is indeed productive and has the potential to generate employment and other important development benefits. That said, there are important limitations created by broader political–economic conditions and deeply entrenched inequalities.  相似文献   

Inorganic carbon dynamics and CO<Subscript>2</Subscript> flux associated with coal-mine drainage sites in Blythedale PA and Lambert WV,USA     

Dorothy J. Vesper  Johnathan E. Moore  James P. Adams 《Environmental Earth Sciences》2016,75(4):340

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Attenuation and diel cycling of coal-mine drainage constituents in a passive treatment wetland: A case study from Lambert Run,West Virginia,USA     

Dorothy J. Vesper  Michael J. Smilley 《Applied Geochemistry》2010

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Parallel Simulation in Subsurface Hydrology: Evaluating the Performance of Modeling Computers     

Theo S. Sarris  David M. Scott  Murray E. Close 《Ground water》2021,59(1):109-116

Monte Carlo uncertainty analysis, model calibration and optimization applications in hydrology, usually involve a very large number of forward transient model solutions, often resulting in computational bottlenecks. Parallel processing can significantly reduce overall simulation time, benefiting from the architecture of modern computers. This work investigates system performance using two realistic flow and transport modeling scenarios, applied to various modeling hardware, to provide information on the expected performance of parallel simulations and inform investment decisions. We investigate how performance, measured in terms of speedup and efficiency, changes with increasing number of parallel processes. We conclude that the maximum performance achieved by parallelization can range from 40% to 100% of the theoretical limit, with the lower increases associated with multi-CPU servers. The number of parallel processes required to maximize performance is application dependent, and in contrast to common practice, often needs to be significantly larger than the total number of system CPU cores. Further testing is required to better understand how the physical problem being simulated affects the optimal number of parallel processes needed. Finally, when laptops are considered for modeling applications, careful consideration should be given not only to the specifications but also to the intended use designated by the manufacturer.  相似文献   

Use of rhodamine WT with XAD-7 resin for determining groundwater flow paths     

Murray E. Close  Greg J. Stanton  Liping Pang 《Hydrogeology Journal》2002,10(3):368-376

A passive sampling system for use with rhodamine WT (RWT) in groundwater tracing experiments was developed to assist in the characterisation of groundwater flow paths. Amberlite XAD-7 resin was found to be suitable for adsorption of RWT, which can then be extracted using an ethanol/water mix and analysed fluorometrically. Batch and column experiments showed that XAD-7 resin has a high RWT capacity. The adsorption was slightly dependent on pH, but was always above 75% under batch conditions. The resin had a high percentage mass recovery at flow velocities around 1.5 m/day, but this decreased with increasing flow velocities. Desorption of RWT off the resin in water is dependent on the flow velocity of water and the time after the peak RWT has passed. The mass of RWT extracted from the resin bags correlated very well with both the RWT mass flux in the water and the peak concentrations observed in the monitoring wells in a field experiment. The results of resin bags were reproducible in the field with a mean coefficient of variation equal to 16%. This method has been successfully applied to two field situations with different flow velocities to indicate groundwater flow paths. Electronic Publication  相似文献   

In-situ measurement of the rate of²³⁵U fission induced by lunar neutrons     

Dorothy S. Woolum  D.S. Burnett 《Earth and Planetary Science Letters》1974,21(2):153-163

The depth profile of the neutron-induced fission rate of²³⁵U was directly measured to a depth of 350 g/cm² by the Apollo 17 Lunar Neutron Probe Experiment. The fission rate rises sharply from the surface to a broad maximum from 110 to 160 g/cm² and drops off at greater depths. The shape of theoretical depth profile of Lingenfelter et al. fits the measured capture rates well at all depths. The absolute magnitude of the experimental fission rates are (11±17)% lower than those calculated theoretically. The excellent agreement between theory and experiment implies that conclusions drawn previously by interpreting lunar sample data with the theoretical capture rates will not require revision. In particular lunar surface processes, rather than uncertainties in the capture rates, are required to explain the relatively low neutron fluences observed for surface soil samples compared to the fluences expected for a uniformly mixed regolith.  相似文献   

The educational value of the history of geomorphology     

Dorothy Sack   《Geomorphology》2002,47(2-4)

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Palynomorph content of the uraniferous alum shales of Cambrian-Ordovician age in Sweden     

Dorothy Guy-Ohlson  Bengt Lindqvist 《Ore Geology Reviews》1990,5(5-6)

Preliminary investigations were carried out on selected samples of different ages from various alum shale localities in order to document palynofacies and content of palynomorphs as well as content and distribution of various minerals and chemical elements. There preliminary results indicate that the shales not only contain a variety of microfossils not previously recorded, but also that these fossils indicate a fresh water or saline influence. The tentative conclusion is that the uranium-bearing alum shales may have been deposited under shallow, brackish conditions with an anoxic bottom environment.  相似文献   

A note on the mineralogy of the Gingin Chalk,Western Australia     

Dorothy Carroll  B.A.  B.Sc. 《Proceedings of the Geologists' Association. Geologists' Association》1939,50(2):227-234

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A Field Study of Nonequilibrium and Facilitated Transport of Cd in an Alluvial Gravel Aquifer   总被引：3，自引：0，他引：3  

Liping Pang  Murray Close 《Ground water》1999,37(5):785-792

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