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71.
Bomers A. Aguilar Lopez J. P. Warmink J. J. Hulscher S. J. M. H. 《Natural Hazards》2018,94(1):493-493
Natural Hazards - The article was published Open Access under the Dutch Compact Agreement; however, due to an internal system error, previous HTML rendering of the article did not reflect this. 相似文献
72.
73.
John D. Lopez Mark S. Peterson Jake Walker Gretchen L. Grammer Mark S. Woodrey 《Estuaries and Coasts》2011,34(1):148-158
The saltmarsh topminnow (Fundulus jenkinsi) is federally listed as a Species of Concern due to a its rarity, impacts from human activities, and lack of information
on its biology and ecology. From 2007 through 2008, we used Breder traps to fish the marsh edge on a falling tide in four
regions from Louisiana through the Florida panhandle during winter, spring, and summer periods. Out of 2,108 Breder traps
deployed, 661 F. jenkinsi were collected as far east as Escambia Bay, Florida, with Weeks Bay, National Estuarine Research Reserve (NERR), Alabama,
yielding the highest F. jenkinsi abundance. Principal component analysis (PCA) was used to ordinate physical–chemical data into two meaningful components:
a geomorphic axis (water depth, bank slope, and plant stem density) and a seasonal/spatial axis of species occurrence (water
temperature, salinity, and turbidity). PCA showed a higher mean catch-per-unit-effort (CPUE) in environments comprised of
low to moderate stem density (<25 stems/0.25 m−2), depth (<25 cm), bank slope (<15°), turbidity (<30 NTU), and salinity (<16) coupled with spring and early summer water temperatures
(>15°C). F. jenkinsi CPUE was significantly higher in Spartina cynosuroides marsh edge compared with five other habitat types, even though it was one of the least sampled habitats. This species appears
to be collected more frequently and in higher CPUE in small dendritic creeks off of main channels than suggested by our previous
work in main channel edge habitat. This suggests that small creeks are important vectors for marsh access and supports the
value of the dendritic nature of salt marshes to marsh residents. 相似文献
74.
Abstract The authors studied the error of spatial interpolation in the context of a climatic data gridding project (Cli‐Grid). Four objective analysis (QA) techniques were implemented: the empirical techniques of Barnes, Cressman and Shepard, and a Gandin‐based statistical technique. These were applied to the interpolation of irregularly distributed daily rainfall data. Spatial resolution of the interpolated arrays was 0.05 degree of latitude by 0.05 degree of longitude. In this experiment, radar rainfall patterns served as reference data for evaluations of O A techniques. Each reference pattern was sampled at the irregularly spaced locations of a climatic rain‐gauge network. The sampled data were then input to one of the four OA techniques. The resulting analysis was subtracted from the corresponding reference pattern. Absolute values of the differences were recorded. This sampling‐to‐difference cycle was repeated with 63 reference patterns. Every map of absolute differences was summed. The resulting map of total errors was normalized by the sum of the reference patterns. Average bias, average RMS error and averages of the ratios of the standard deviations were also computed. All four OA techniques were evaluated separately. The authors recognized that totally unbiased intercomparisons were not possible because of the range in execution parameters for each OA technique. Reasonable efforts were made to minimize subjectivity in the setting of parameters. For application to the specific project grid, the statistical optimal interpolation technique displayed the lowest RMS errors. This technique and Shepard OA, were found more suitable than the other two techniques studied. Statistical and Barnes OA displayed zero average bias and would be useful for areal average computations. The Cressman OA was judged least suitable for interpolation of daily rainfall. An application of the two‐dimensional error maps to network analysis was demonstrated by plotting the relationship between interpolation errors and distance (D) from the closest station. Error increased as D1/2. It was also verified that error and station density were inversely related. 相似文献
75.
N. Prithivikumaran M. Fernandez Gomez J.J. Lopez Gonzalez S.P. Bagare N. Rajamanickam 《Astrophysics and Space Science》2002,280(4):319-324
The Franck-Condon (FC) factors (transition probabilities) and r-centroids have been evaluated by the reliable numerical integration procedure for the bands of the A
3 φ4 →X
3 φ4 system of astrophysical molecule CoH, using a suitable potential. The dissociation energy D
0
0 = 2.5 ± 0.05 eV for the electronic ground state of CoH has been estimated by fitting Hulburt-Hirschfelder function to the
experimental potential energy curve, using the correlation coefficient.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
76.
Ch. Leinert U. Graser F. Przygodda L.B.F.M. Waters G. Perrin W. Jaffe B. Lopez E.J. Bakker A. Böhm O. Chesneau W.D. Cotton S. Damstra J. de Jong A.W. Glazenborg-Kluttig B. Grimm H. Hanenburg W. Laun R. Lenzen S. Ligori R.J. Mathar J. Meisner S. Morel W. Morr U. Neumann J.-W. Pel P. Schuller R.-R. Rohloff B. Stecklum C. Storz O. von der Lühe K. Wagner 《Astrophysics and Space Science》2003,286(1-2):73-83
After more than five years of preparation, the mid-infrared interferometric instrument MIDI has been transported to Paranal
where it will undergo testing and commissioning on theVery Large Telescope Interferometer VLTI from the end of 2002through
large part of this year 2003. Thereafter it will be available as a user instrument to perform interferometric observations
over the8 μm–13 μm wavelength range, with a spatial resolution of typically 20 milliarcsec, a spectral resolution of up to
250, and an anticipated point source sensitivity of N = 3–4 mag or 1–2.5 Jy for self –fringe tracking, which will be the only
observing mode during the first months of operation. We describe the layout of the instrument, laboratory tests, and expected
performance, both for broadband and spectrally resolved observing modes. We also briefly outline the planned guaranteed time
observations.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
77.
James Yan Tse J. B. Hearnshaw P. Rosenzweig E. Guzman O. Escalona A. C. Gilmore P. M. Kilmartin L. C. Watson 《Monthly notices of the Royal Astronomical Society》2001,324(3):553-559
The light curve and spectra of Nova Centauri 1995 (V888 Cen) are analysed. The spectra were obtained a few days post-maximum. The nova is found to be a very fast nova, declining by 2 mag within about 5±2 d of maximum. The light curve shows strong oscillations in the transition region, of peak-to-peak amplitude about 1.5 mag and period 12–15 d. The light curve of Nova Centauri resembles closely that of Nova Aquilae 1918 (V603 Aql).
The early blue and red spectra obtained at Mt John show broad emission lines, many with P Cygni profiles. The absorption lines are found in two velocity systems at about −1765 and −3010 km s−1 , in respectively the principal and diffuse-enhanced stages of spectral development, as defined by McLaughlin. Nova Centauri has many Fe ii lines in emission, indicating that it is a member of the Williams Fe ii class of classical novae. 相似文献
The early blue and red spectra obtained at Mt John show broad emission lines, many with P Cygni profiles. The absorption lines are found in two velocity systems at about −1765 and −3010 km s
78.
The classical treatment of implied differences on the orbital ellipticelements from the errors involved at an initial epoch is not possible toapply if we consider a long interval of integration, because there is atemporal variation for all the partial derivatives of the elements withrespect to all the variations in the initial ones. We propose asemi-analytical method to compute these partial derivatives by solving a setof initial value problems which are obtained from the planetary Lagrangeequations and their partial derivatives with respect to all the variationsin the initial elements. 相似文献
79.
80.
Exhumation history and timing of supergene copper mineralisation in an arid climate: New thermochronological data from the Centinela District,Atacama, Chile 总被引:1,自引:0,他引:1
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Caroline Sanchez Stéphanie Brichau Rodrigo Riquelme Sébastien Carretier Thomas Bissig Cristopher Lopez Constantino Mpodozis Eduardo Campos Vincent Regard Gérard Hérail Carlos Marquardt 《地学学报》2018,30(1):78-85
Supergene copper mineralisation (SCM) processes occur during the unroofing of porphyry copper deposits. However, the geomorphological stage during which the main mineralisation occurs is still under debate. Here, we present 24 new thermochronological data from Cenozoic intrusives and compare them with the evolution of supergene mineralisation from the Centinela Mining District in the Atacama Desert. Our results indicate a two‐step cooling path: a rapid Late Eocene exhumation followed by a slow denudation. Previously published supergene mineralisation ages cluster after the main Upper Oligocene exhumation period. Ours is the first study that establishes the relationship between exhumation and supergene processes on the scale of a single mining district. It confirms that SCM took place during pediplanation, likely a required condition for efficient SCM under arid climatic conditions, in contrast to wet tropical environments where SCM occurs during rapid relief growth but has limited preservation potential. 相似文献