The 2dF Galaxy Redshift Survey: galaxy clustering per spectral type     

Darren S. Madgwick  Ed Hawkins  Ofer Lahav  Steve Maddox  Peder Norberg  John A. Peacock  Ivan K. Baldry  Carlton M. Baugh  Joss Bland-Hawthorn  Terry Bridges  Russell Cannon  Shaun Cole  Matthew Colless  Chris Collins  Warrick Couch  Gavin Dalton  Roberto De Propris  Simon P. Driver  George Efstathiou  Richard S. Ellis  Carlos S. Frenk  Karl Glazebrook  Carole Jackson  Ian Lewis  Stuart Lumsden  Bruce A. Peterson  Will Sutherland  Keith Taylor 《Monthly notices of the Royal Astronomical Society》2003,344(3):847-856

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The 2dF Galaxy Redshift Survey: the population of nearby radio galaxies at the 1-mJy level     

Manuela Magliocchetti  Steve J. Maddox  Carole A. Jackson  Joss Bland-Hawthorn  Terry Bridges  Russell Cannon  Shaun Cole  Matthew Colless  Chris Collins  Warrick Couch  Gavin Dalton  Roberto de Propris  Simon P. Driver  George Efstathiou  Richard S. Ellis  Carlos S. Frenk  Karl Glazebrook  Ofer Lahav  Ian Lewis  Stuart Lumsden  John A. Peacock  Bruce A. Peterson  Will Sutherland  Keith Taylor 《Monthly notices of the Royal Astronomical Society》2002,333(1):100-120

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The Galileo star scanner observations at Amalthea     

Paul D Fieseler  Olen W Adams  Nancy Vandermey  E.E Theilig  Kathryn A Schimmels  George D Lewis  Shadan M Ardalan  Claudia J Alexander 《Icarus》2004,169(2):390-401

In November of 2002, the Galileo spacecraft passed within 250 km of Jupiter's moon Amalthea. An onboard telescope, the star scanner, observed a series of bright flashes near the moon. It is believed that these flashes represent sunlight reflected from 7 to 9 small moonlets located within about 3000 km of Amalthea. From star scanner geometry considerations and other arguments, we can constrain the diameter of the observed bodies to be between 0.5 m to several tens of kilometers. In September of 2003, while crossing Amalthea's orbit just prior to Galileo's destruction in the jovian atmosphere, a single additional body seems to have been observed. It is suspected that these bodies are part of a discrete rocky ring embedded within Jupiter's Gossamer ring system.  相似文献   

The 2dF Galaxy Redshift Survey: the clustering of galaxy groups     

Nelson D. Padilla  Carlton M. Baugh  Vincent R. Eke  Peder Norberg  Shaun Cole  Carlos S. Frenk  Darren J. Croton  Ivan K. Baldry  Joss Bland-Hawthorn  Terry Bridges  Russell Cannon  Matthew Colless  Chris Collins  Warrick Couch  Gavin Dalton  Roberto De Propris  Simon P. Driver  George Efstathiou  Richard S. Ellis  Karl Glazebrook  Carole Jackson  Ofer Lahav  Ian Lewis  Stuart Lumsden  Steve Maddox  Darren Madgwick  John A. Peacock  Bruce A. Peterson  Will Sutherland  Keith Taylor 《Monthly notices of the Royal Astronomical Society》2004,352(1):211-225

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Near‐infrared spectroscopy of a hydroecological indicator: new tool for determining sustainable yield for Floridan aquifer system     

Sydney T. Bacchus  Douglas D. Archibald  George A. Brook  Kerry O. Britton  Bruce L. Haines  Stephen L. Rathbun  Marguerite Madden 《水文研究》2003,17(9):1785-1809

Pond‐cypress (Taxodium ascendens Brong.) is a dominant canopy species in depressional wetlands of the south‐eastern Coastal Plain. Unsustainable withdrawals from the karst Floridan aquifer system have caused premature decline and death of pond‐cypress trees, presumably owing to altered hydroperiods (which alter the flow of water and nutrients in trees). There has been no scientifically based means to determine sustainable yield from this regional aquifer system or to detect early stages of physical/ecological damage associated with groundwater mining and aquifer storage and recovery (ASR, which also can alter natural hydroperiods). In this study, the relationship between visual symptoms (indicators) of stress or premature decline, and spectral reflectance was evaluated using dried, milled branch tips collected from natural stands of mature pond‐cypress. Depressional systems evaluated represented four of the six aquifer system subregions where subsurface perturbations from groundwater mining: (i) were presumed not to be occurring (reference wetlands); (ii) may be occurring but are not documented; and (iii) have been confirmed. Sampled trees were assigned to one of three stress classes (1, no/minimal; 2, moderate; 3, severe) based on the visual indicators. Partial least squares–linear discriminant analysis of second derivative spectral transformations in the visible/shortwave near‐infrared (NIR) region (400–1100 nm) and the NIR region (1100–2500 nm) was used to evaluate the samples in assigned classes. Class 1 samples were discriminated from combined class 2 and 3 samples in the NIR region with 100% and 97% accuracy for consecutive winter sample periods (before bud‐break). The percentage of correctly classified samples in this spectral region was lower (85%) for summer samples (full leaf‐out). Second‐derivative models for the NIR region developed from the winter data sets predicted assigned classes for alternate winter's samples with an accuracy of 97% and 100%. High correlation between spectral reflectance of dried, milled branch tips collected from mature pond‐cypress in winter and visual indicators of premature decline suggests in situ pond‐cypress are hydroecological indicators of anthropogenic subsurface hydroperiod perturbations. This approach provides objective means for early detection of unsustainable aquifer yield and adverse impacts from ASR activities in the south‐eastern Coastal Plain. Used in conjunction with hydrological monitoring and modelling, the hydroecological indicators should provide the means with which sustainable yield in the south‐eastern Coastal Plain can be achieved and maintained. Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   

Evaluation of archaeological site potential on the Tall al-Kharrar area (Jordan) using magnetic and resistivity methods     

Awni Batayneh  Abdallah Al-Zoubi  Ula Tobasi  George Haddadin 《Environmental Geology》2001,41(1-2):54-61

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Earliest stegosaur dinosaur     

Brian F.W. Boneham  George F. Forsey 《地学学报》1992,4(6):628-632

Re-excavation of the type site of the Sharp's Hill Formation (Bathonian, Middle Jurassic) in Oxfordshire, England, has revealed several horizons with disarticulated remains of a species of stegosaurian dinosaur, here considered to be the earliest stegosaur. It is suggested that stegosaurs radiated out from northern Europe in the Middle and Upper Jurassic to the rest of the world. The general stratigraphy of the type site is described, and it is concluded that the stegosaur remains are possibly of earliest Lower Bathonian age. The sediment in which the remains accumulated is considered to represent a drought-controlled environment.  相似文献   

An appeal     

George Joseph 《Journal of the Indian Society of Remote Sensing》1994,22(4):N1-N1

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Cosmology in South Africa     

George F. R. Ellis 《Astrophysics and Space Science》1995,230(1-2):237-262

This paper reviews research in theoretical cosmology in South Africa, providing an overview of the work that has been done and the groups involved in that work.  相似文献   

Chemical abundance analysis of Kapteyn's Star     

Vincent M. Woolf  George Wallerstein † 《Monthly notices of the Royal Astronomical Society》2004,350(2):575-579

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