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A method for semi-automatic background estimation in energy-dispersive x-ray fluorescence spectra is outlined. Two cubic splines were investigated and the spline called the Butland interpolant was chosen for further investigation. Prior to the calculation of the spline, peak regions are set up, and suitable knots are defined outside the peak regions. To set up the peak regions, an automatic peak-search routine and a calibration equation are used. For a given peak, the latter relates the full width at half maximum (FWHM) to the peak centre. In turn, the size of the peak regions are defined by the FWHM multiplied by a constant given by the user. The method was tested on several types of spectra. It was found that the optimal size of the peak region decreased with increasing peak density. Reproducibility tests showed that the standard deviation of the summation of counts within a peak region and after background subtraction was less than would be expected from the counting statistics. 相似文献
3.
Abstract We analyze the efficiency of the international management of the Bay of Biscay anchovy. While a sharing agreement between France and Spain has been in place since 1992, the fish stock collapsed in 2005 and the fishery closed from 2005 to spring 2010. We consider differences in production technologies between both countries and calibrate our model using data from 1987 to 2009. Our results suggest two sources of rent dissipation under the existing sharing agreement: inefficient quota allocation and production inefficiencies due to inflexible national regulations. We discuss several alternatives to improve management. 相似文献
4.
Steffen Huck Hans-Theo Normann Jörg Oechssler 《International Journal of Game Theory》2002,31(1):123-136
We report results of experiments designed to test the predictions of the best-reply process. In a Cournot oligopoly with
four firms, the best-reply process should theoretically explode if demand and cost functions are linear. We find, however,
no experimental evidence of such instability. Moreover, we find no differences between a market which theoretically should
not converge to Nash equilibrium and one which should converge because of inertia. We investigate the power of several learning
dynamics to explain this unpredicted stability.
Received May 1997/Revised June 2002 相似文献
5.
CLAUDIA L. PARKER OSCAR N. VENTURA STAN K. BURT RAÚL E. CACHAU 《Molecular physics》2013,111(17):2659-2668
We present a general purpose QM-MM-MD engine (DYNGA) designed to test alternative hybrid Hamiltonians geared towards the treatment of problems of interest in structural biology including the use of experimental data constraints. In this first presentation we use DYNGA to explore the behaviour of a traditional QM-MM approach in the treatment of the water—water interaction. We find the potential energy hypersurface for the water dimer computed with the HF 4–31G*/TIP3P hybrid Hamiltonian tends to be too flat. We also explore the effect of using traditional QM-MM techniques on proton wires and conclude there is a need for improvement, possibly addressed by using polarizable force fields. 相似文献
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Fr. Gisiger H. Kreis W. Normann und H. Herbst 《Fresenius' Journal of Analytical Chemistry》1928,73(5-6):238
Ohne Zusammenfassung 相似文献
9.
J. Großfeld A. Simmer J. van Loon W. Springer S. Juschkewitsch V. Kubelka J. Wagner S. Zuravlev Thompsonwerke W. Normann H. P. Trevithik M. F. Lauro A. Bömer A. Gehrke G. de Belsunce J. I. Lurje F. Fritz Zitek R. Otto A. Halter J. M. Purdy W. G. France W. L. Evans H. P. Kaufmann und M. Keller 《Fresenius' Journal of Analytical Chemistry》1931,83(5-6):223-230
Ohne Zusammenfassung 相似文献
10.
Dag Normann 《Archive for Mathematical Logic》2002,41(8):721-741
We show how Kreisel's representation theorem for sets in the analytical hierarchy can be generalized to sets defined by positive
induction and use this to estimate the complexity of constructions in the theory of domains with totality.
Received: 21 January 1998 / Published online: 2 September 2002 相似文献