Pumping Test Analysis for a Tidally Forced Aquifer   总被引：3，自引：0，他引：3  

Michael G. Trefry  Colin D. Johnston 《Ground water》1998,36(3):427-433

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Voting power in the E.E.C.'s council of ministers: An essay on method in political geography     

R.J. Johnston  A.J. Hunt 《Geoforum》1977,8(1):1-9

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Preliminary results from a search for regional tectonomagnetic effects in California and western Nevada     

M.J.S. Johnston 《Tectonophysics》1974,23(3):267-275

Physical theory and laboratory experiments both indicate that tectonomagnetic effects in seismically active areas should be detected with highly sensitive drift-free differential magnetometers. By using a pair of synchronized 0.25 7 absolute magnetometers to measure precisely field differences between 70 adjacent sites with a 10–15 km separation, more than 1,000 km of faults in California and western Nevada have been monitored for anomalous changes in the local magnetic field. Over a nine-month period, four sets of mea surements have been completed along 350 km of the San Andreas and two sets along the Excelsior Mountains, Mono Lake, and Owens Valley. Preliminary results show that significant changes have occurred between each subsequent data set and that these changes appear to be related to tectonic structure and seismicity. This method looks promising as a simple inexpensive scheme for indicating some hazardous sections of active faults, particularly in countries where extensive geophysics programs are not feasible.  相似文献   

GEOGRAPHIC NOTEBOOK: THE PHYSICAL ENVIRONMENT CONFERENCE, MAY 1970     

W. B. Johnston 《New Zealand geographer》1971,27(1):87-89

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Radio galaxies in the 2SLAQ Luminous Red Galaxy Survey – I. The evolution of low-power radio galaxies to  z∼ 0.7      

Elaine M. Sadler  Russell D. Cannon  Tom Mauch  Paul J. Hancock  David A. Wake  Nic Ross  Scott M. Croom  Michael J. Drinkwater  Alastair C. Edge  Daniel Eisenstein  rew M. Hopkins  Helen M. Johnston  Robert Nichol  Kevin A. Pimbblet  Roberto De Propris  Isaac G. Roseboom  Donald P. Schneider  Tom Shanks 《Monthly notices of the Royal Astronomical Society》2007,381(1):211-227

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A review of the assessments of the major fisheries resources in South Africa     

CL de Moor  SJ Johnston  A Brandão  RA Rademeyer  JP Glazer  LB Furman 《African Journal of Marine Science》2015,37(3):285-311

The waters off South Africa's coastline boast a rich mix of commercially fished species. Quantitative assessments of these marine resources have developed from simple methods first applied in the 1970s, to models that encompass a wide range of methodologies. The more valuable resources have undergone regular assessments in recent decades, with frequencies closely related to the management approach employed for each fishery. Many of these assessments form the operating models used to simulation-test candidate management procedures. This paper provides a comprehensive review of the assessments of 11 of the most important fisheries resources in South Africa. Some assessments use simple biomass dynamics models, whereas others are a hybrid of age- and length-based models, each designed to model the specific characteristics of the resource and fishery concerned. Many of the assessments have been disaggregated by species/stock and/or area as related multispecies/stock/ distribution hypotheses have arisen. This paper explores the similarities and differences in the data available and the methods applied. The review indicates that, whereas the status of three of these resources cannot be estimated reliably at present, the status of six resources is considered to be reasonable to good, whereas that of abalone Haliotis midae and West Coast rock lobster Jasus lalandii remains poor.  相似文献   

State of the art of modelling two-phase flow in fractured rock     

Z. Wanfang  H. S. Wheater  P. M. Johnston 《Environmental Geology》1997,31(3-4):157-166

 Two-phase flow in fractured rock is an important phenomenon for a range of practical problems, not the least of which is non-aqueous phase liquid (NAPL) contamination of groundwater. Although multiphase systems have long been studied in the petroleum field, in the hydrogeological field progress has only just reaches the point where models are being developed. Scale effect is one of the main issues of concern. Although models presented in this paper have the potential to provide useful predictions, they can only be used to investigate a variety of possible scenarios with parameters being specified in the form of distribution of values. The calibration and validation of all but the simplest of these models poses a formidable task, with great demands on hydrogeologists and geophysicists to provide adequate data. Received: 20 May 1996 · Accepted: 19 August 1996  相似文献   

The magnetic field structure of SNR G328.4+0.2 from polarimetric observations at 19 GHz     

Simon Johnston  N. M. McClure-Griffiths  Bärbel Koribalski 《Monthly notices of the Royal Astronomical Society》2004,348(2):L19-L22

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Single pulses from PSR B1641–45     

Simon Johnston 《Monthly notices of the Royal Astronomical Society》2004,348(4):1229-1235

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A search for giant pulses in Vela-like pulsars     

Simon Johnston  Roger W. Romani 《Monthly notices of the Royal Astronomical Society》2002,332(1):109-115

We have carried out a survey for 'giant pulses' in six young, Vela-like pulsars. In no cases did we find single pulses with flux densities more than 10 times the mean flux density. However, in PSR  B1706–44  we have detected giant micro-pulses very similar to those seen in the Vela pulsar. In PSR  B1706–44  these giant micro-pulses appear on the trailing edge of the profile and have an intrinsic width of ∼1 ms. The cumulative probability distribution of their intensities is best described by a power law. If the power law continues to higher intensities, then  3.7×10⁶  rotations are required to obtain a pulse with 20× the mean pulse flux. This number is similar to the giant pulse rate in PSR B1937+21 and PSR  B1821–24  but significantly higher than that for the Crab.  相似文献