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951.
K. M. Evans 《Geological Journal》1983,18(4):297-305
The Lynton Beds represent shallow marine sediments with a restricted fauna dominated by brachiopods. The age indicated by the brachiopod fauna is late Emsian, although the possibility of a younger date for the uppermost horizons cannot be discounted. 相似文献
952.
953.
G. A. Richter P. Notni F. Brngen V. Afanasjev I. D. Karachentsev A. Kopylov 《Astronomische Nachrichten》1981,302(5):211-218
With the aid of silt spectrograms gained at the 6 meter telescope Selenchukskaja and at the 2 meter telescope Tautenburg a brightness outburst (the only one so far observed) could be followed up spectroscopically. The spectral behaviour resembles SS Cygni, but the presence of CIII and NIII emission is not typical of dwarf novae. Possibly the object is related to the anomalous recurrent nova WZ Sge. The definite determination of its belonging to a known subclass of cataclysmic variables will be possible only after obtainment of extensive photometric material. 相似文献
954.
G. A. Richter 《Astronomische Nachrichten》1979,300(3):117-119
52 possible optical identifications (V ≲ 19.5) of 43 radio sources of the 5C3 area have been spectroscopically examined by use of objective prism plates from KARL SCHWARZSCHILD Observatory Tautenburg. The aim was to select objects of special interest for further slit spectrographic investigation. Besides 42 probably ordinary stars and 3 galaxies, five quasar spectra have been found, but only one redshift could be determined. Two further objects probably have unusual spectra. 相似文献
955.
956.
957.
Elvis A. Shukla Jagdish Prasad M. S. S. Nagaraju Rajeev Srivastava D. L. Kauraw 《Journal of the Indian Society of Remote Sensing》2009,37(1):129-137
Soil resource characterization of Dhamni micro-watershed in Chandrapur district of Maharashtra was carried out using IRS-1D
LISS-III data in conjunction with field survey and ancillary data. The study indicates that nearly 84.2 per cent of the total
geographical area of the watershed is under cultivation. Forest (mainly degraded) occupy only 4.5 per cent area Whereas wasteland
with scrub cover 9.4 per cent area of the watershed. Nine soil series were tentatively identified and mapped as soil series
association in to five mapping units. These soils belong to order Inceptisol, Vertisol and Mollisol. Except the soils of wasteland
with scrub, other soils are moderately suitable for pigeonpea and soybean and have average to good productivity. 相似文献
958.
Nonnegative matrix factorization (NMF) is a recently developed linear unmixing technique that assumes that the original sources and transform were positively defined. Given that the linear mixing model (LMM) for hyperspectral data requires positive endmembers and abundances, with only minor modifications, NMF can be used to solve LMM. Traditionally, NMF solutions include an iterative process resulting in considerable execution times. In this letter, we provide two novel algorithms aimed at speeding the NMF through parallel processing: the first based on the traditional multiplicative solution and the second modifying an adaptive projected gradient technique known to provide better convergence. The algorithms' implementations were tested on various data sets; the results suggest that a significant speedup can be achieved without decrease in accuracy. This supports the further use of NMF for linear unmixing. 相似文献
959.
I. A. Mel’nikov 《Oceanology》2008,48(6):888-890
960.
O. I. Podymov 《Oceanology》2008,48(5):656-663
A problem-oriented database (PODB) was developed for the statistical analysis of the hydrochemical characteristics of the redox layer of the Black Sea. The paper describes the features of the PODB, including the algorithm of interpolation and the location of the levels of the appearance and disappearance of hydrochemical parameters (the so-called onset levels) based on Akima’s spline. The application of the PODB allowed us to obtain a series of biogeochemical estimates, in particular, (1) to reveal the constancy of the vertical gradients of the hydrochemical parameters at selected density levels; (2) to calculate the seasonal variability of the degree of manifestation of the phosphate minimum in the near-shore and open sea areas; and (3) to calculate the interannual variability of the level of the disappearance of the hydrogen sulfide, ammonium, total manganese, and methane, as well as the oxygen content in the cold intermediate layer, and to find out their relations with the climatic variations. 相似文献