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951.
Janko Drnovšek Igor Pušnik Jovan Bojkovski Gaber Begeš 《Accreditation and quality assurance》2010,15(2):125-131
The article describes the project of regional cooperation in proficiency testing within CARDS 2006 (assistance programme to
the Western Balkans), which was coordinated by European Committee for Standardization, European Commission and European Free
Trade Association and conducted by the University of Ljubljana, Faculty of Electrical Engineering, Laboratory of Metrology
and Quality. The later is the holder of the national standard for thermodynamic temperature as well as an accredited proficiency
testing provider and also accredited as a calibration, testing and inspection laboratory. It is also responsible for graduate
study programme Quality Engineering. Proficiency testing was considered as a core activity of the entire project, but additionally
as a very appropriate platform for knowledge transfer of EU technical legislation in selected sectors, metrology, testing
and quality assurance in general. The project had a high added value for participating laboratories in countries of Western
Balkans, because it required an active role of all participating laboratories, assured participation of staff from national
metrology institutions, all national accreditation bodies, and was supported by national quality infrastructures, such as
standardization, governmental institutions etc. in the entire Western Balkans region. The activities stimulated progress in
the area of conformity assessment, added knowledge to the implementation of technical directives and development of the technical
part of national legislation and therefore facilitated the process toward the accession to the European Union. The main objective
was therefore to organize proficiency testing in those sectors (construction, consumer protection and environment) that were
vital in the pre-accession process of countries seeking full implementation of EU technical legislation. 相似文献
952.
In this paper the response of an amperometric biosensor at mixed enzyme kinetics and diffusion limitations is modelled in
the case of the substrate and the product inhibition. The model is based on non-stationary reaction–diffusion equations containing
a non-linear term related to non-Michaelis–Menten kinetics of an enzymatic reaction. A numerical simulation was carried out
using a finite difference technique. The complex enzyme kinetics produced different calibration curves for the response at
the transition and the steady-state. The biosensor operation is analysed with a special emphasis to the conditions at which
the biosensor response change shows a maximal value. The dependence of the biosensor sensitivity on the biosensor configuration
is also investigated. Results of the simulation are compared with known analytical results and with previously conducted researches
on the biosensors. 相似文献
953.
954.
955.
A. A. Kulko N. K. Skobelev V. Kroha V. Burjan Z. Hons A. V. Daniel N. A. Demekhina R. Kalpakchieva A. Kugler J. Mrázek Yu. E. Penionzhkevich Š. Piskoř Yu. G. Sobolev E. Šimečková 《Bulletin of the Russian Academy of Sciences: Physics》2011,75(4):538-543
Experimental excitation functions are presented for 45Sc(d, p)46Sc, 45Sc(d, t)44Sc, 45Sc(6He, 5He*)46Sc and 45Sc(6He, α)47Sc reactions at projectile energies near the Coulomb barrier. The obtained excitation functions for reactions 45Sc(d, p)46Sc and 45Sc(6He, 5He*)46Sc have similar behavior and have a maxima near the Coulomb barriers of these reactions. The compilation of the available experimental data, obtained at deuteron- and 6He-energies near the Coulomb barrier, showed that the values of the cross sections at the maxima of the excitation functions obtained in (d, p) reactions and the reactions for one-neutron pickup from the 6He projectiles have a different Z-dependence. 相似文献
956.
Martín Egozcue Luis Fuentes García Wing-Keung Wong Ričardas Zitikis 《Central European Journal of Mathematics》2011,9(6):1288-1297
We show that Grüss-type probabilistic inequalities for covariances can be considerably sharpened when the underlying random
variables are quadrant dependent in expectation (QDE). The herein established covariance bounds not only sharpen the classical
Grüss inequality but also improve upon recently derived Grüss-type bounds under the assumption of quadrant dependency (QD),
which is stronger than QDE. We illustrate our general results with examples based on specially devised bivariate distributions
that are QDE but not QD. Such results play important roles in decision making under uncertainty, and particularly in areas
such as economics, finance, and insurance. 相似文献
957.
Different non-exponential decays such as the concave and the convex double sloped decays in the coupled rooms provide distinct sound qualities. These are commonly considered to occur in the less reverberant sub-room and the more reverberant sub-room, respectively. However, numerical simulations and experiments in this paper show that the demarcation line is not located along the physical boundaries (e.g., the partition and the coupling aperture), but in the more reverberant sub-room. The sound field with the concave double sloped decay penetrates into the auxiliary sub-room to an extent which is influenced by the difference between the two natural reverberations of the sub-rooms. Furthermore the sound energy flows in different regions are investigated, demonstrating how energy feedback leads to the concave double sloped decay. 相似文献
958.
Dunlop MW Zhang QH Bogdanova YV Lockwood M Pu Z Hasegawa H Wang J Taylor MG Berchem J Lavraud B Eastwood J Volwerk M Shen C Shi JK Constantinescu D Frey H Fazakerley AN Sibeck D Escoubet P Wild JA Liu ZX 《Physical review letters》2011,107(2):025004
The extent of where magnetic reconnection (MR), the dominant process responsible for energy and plasma transport into the magnetosphere, operates across Earth's dayside magnetopause has previously been only indirectly shown by observations. We report the first direct evidence of X-line structure resulting from the operation of MR at each of two widely separated locations along the tilted, subsolar line of maximum current on Earth's magnetopause, confirming the operation of MR at two or more sites across the extended region where MR is expected to occur. The evidence results from in-situ observations of the associated ion and electron plasma distributions, present within each magnetic X-line structure, taken by two spacecraft passing through the active MR regions simultaneously. 相似文献
959.
Vossen A Seidl R Adachi I Aihara H Aushev T Balagura V Bartel W Bischofberger M Bondar A Bračko M Browder TE Chang MC Chen A Chen P Cheon BG Cho K Choi Y Eidelman S Feindt M Gaur V Gabyshev N Garmash A Golob B Perdekamp MG Haba J Hayasaka K Horii Y Hoshi Y Hou WS Hyun HJ Inami K Ishikawa A Iwabuchi M Iwasaki Y Iwashita T Joshi NJ Kichimi H Kim HO Kim MJ Ko BR Kumita T Lange JS Lee MJ Lee SH Leitgab M Li Y Liu C Liventsev D Louvot R McOnie S Miyata H Miyazaki Y Mizuk R Mohanty GB Nakano E 《Physical review letters》2011,107(7):072004
The interference fragmentation function translates the fragmentation of a quark with a transverse projection of the spin into an azimuthal asymmetry of two final-state hadrons. In e(+)e(-) annihilation the product of two interference fragmentation functions is measured. We report nonzero asymmetries for pairs of charge-ordered π(+)π(-) pairs, which indicate a significant interference fragmentation function in this channel. The results are obtained from a 672 fb(-1) data sample that contains 711 × 10(6) π(+)π(-) pairs and was collected at and near the Υ(4S) resonance, with the Belle detector at the KEKB asymmetric-energy e(+)e(-) collider. 相似文献
960.
Nonequilibrium interplay between charge, spin, and lattice degrees of freedom on a square lattice is studied for a single charge carrier doped in the t-J-Holstein model. In the presence of a static electric field we calculate the quasistationary state. With increasing electron-phonon (e-ph) coupling the carrier mobility decreases; however, we find increased steady state current due to e-ph coupling in the regime of negative differential resistance. We explore the distribution of absorbed energy between the spin and the phonon subsystem. For model parameters as relevant for cuprates, the majority of the gained energy flows into the spin subsystem. 相似文献