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361.
A. Junker und G. Bergmann 《Fresenius' Journal of Analytical Chemistry》1976,278(3):191-198
Zusammenfassung Für die objektive Beurteilung und Auswahl von Meßpunkten aus überbestimmten spektrometrischen Vielkomponentensystemen werden als Bewertungskriterien die neuen Begriffe der Distension ¯85vj27l132g70k/xxlarge977.gif" alt="thetav" align="BASELINE" BORDER="0"> und der Systemdistension 85vj27l132g70k/xxlarge920.gif" alt="THgr" align="BASELINE" BORDER="0"> = ¯85vj27l132g70k/xxlarge977.gif" alt="thetav" align="BASELINE" BORDER="0">i eingeführt. Beide geben ein quantitatives Maß der Selektivität einzelner Meßstellen in Relation zu den übrigen bzw. mit ihrem Mittelwert Aussagen über die Distension 85vj27l132g70k/xxlarge920.gif" alt="THgr" align="BASELINE" BORDER="0"> eines Mehrkomponentensystems. Die Distension 85vj27l132g70k/xxlarge920.gif" alt="THgr" align="BASELINE" BORDER="0"> erlaubt die optimale Reduzierung eines mehrfach überbestimmten Systems und somit auch die Auswahl optimaler Meßpunkte eines zunächst kontinuierlich vermessenen Systems. Rechenverfahren zur Bestimmung der Distension und der anschließenden Optimierung überbestimmter Systeme werden angegeben und an Beispielen erläutert.Ergänzt wird die 85vj27l132g70k/xxlarge920.gif" alt="THgr" align="BASELINE" BORDER="0">-Optimierung durch eine 85vj27l132g70k/xxlarge8222.gif" alt="ldquor" align="MIDDLE" BORDER="0">längendiskriminierende85vj27l132g70k/xxlarge8220.gif" alt="ldquo" align="MIDDLE" BORDER="0"> Vorauswahl von geeigneten Meßpunkten aus kontinuierlichen Spektren durch Maximierung der Differenzspektren gegenüber den Summenspektren der übrigen Gemischkomponenten.Der Unterschied der 85vj27l132g70k/xxlarge920.gif" alt="THgr" align="BASELINE" BORDER="0">-Optimierung zur Empfindlichkeitsoptimierung wird diskutiert.
Selection, comparison and valuation of optimum working conditions for quantitative multicomponent analysisII. Selection of optimum measuring points by means of the distension of the calibration matrix
Two new terms for the critical classification and selection of measuring points in spectrochemical multicomponent analysis are introduced: the distension 85vj27l132g70k/xxlarge977.gif" alt="thetav" align="BASELINE" BORDER="0"> and the distension of the system 85vj27l132g70k/xxlarge920.gif" alt="THgr" align="BASELINE" BORDER="0"> = ¯85vj27l132g70k/xxlarge977.gif" alt="thetav" align="BASELINE" BORDER="0">i. Both terms give a quantitative relation of the selectivity of any single point of a spectrum with respect to the others and incorporate a measure of the overall-distension of a system. The distension allows the optimal reduction of a multiple overdetermined system and the optimal selection of the best points to be taken from a continuously measured spectrum. Procedures for the calculation of 85vj27l132g70k/xxlarge920.gif" alt="THgr" align="BASELINE" BORDER="0"> and for the optimization which follows are given and demonstrated.The angle-dependent 85vj27l132g70k/xxlarge920.gif" alt="THgr" align="BASELINE" BORDER="0">-optimization is preceded by an 85vj27l132g70k/xxlarge8220.gif" alt="ldquo" align="MIDDLE" BORDER="0">length-discriminating85vj27l132g70k/xxlarge8221.gif" alt="rdquo" align="MIDDLE" BORDER="0"> preselection of points of a continuously measured spectrum; this is done by comparing the difference spectra of all compounds with respect to the sum spectra.相似文献
362.
D. V. Vassilevich 《Letters in Mathematical Physics》1992,26(2):147-152
An algebraic technique of separation of gauge modes in Abelian gauge theories on homogeneous spaces is proposed. An effective potential for the Maxwell-Chern-Simons theory on S
3 is calculated. A generalization of the Chern-Simons action is suggested and analyzed with the example of SU(3)/U(1) X U(1). 相似文献
363.
Sadia Ameen S.G. Ansari Minwu Song Young Soon Kim Hyung-Shik Shin 《Superlattices and Microstructures》2009,46(5):745-751
The work reports on the fabrication of a p–n heterojunction structure comprised of polyaniline (PANI) and TiO2 nanoparticles. PANI was deposited by plasma enhanced polymerization on TiO2 thin film substrates. The structural and the crystalline properties demonstrated the coherence and the substantive interaction of the plasma polymerized PANI molecules with the TiO2 nanoparticle thin film. The UV–Vis studies of PANI/TiO2 thin film supported the internalization of PANI with TiO2 nanoparticles due to π–π* transition of the phenyl rings with the lone pair electrons () of the nitrogen atom present in the PANI molecules. The I–V characteristics of the PANI/TiO2 heterojunction structure were obtained in the forward and the reverse biased at applied voltage ranging from −1 V to +1 V with a scan rate of 2 mV/s. The proficient current in the PANI/TiO2 heterojunction structure was attributed to the well penetration of PANI molecules into the pores of the TiO2 nanoparticle thin film. The I–V characteristics ensured an efficient charge movement at the junction of PANI/TiO2 interface and thus, behaved as a typical ohmic system. 相似文献
364.
The main result is to show that the space of nonmonotonic fuzzy measures on a measurable space (X,X) with total variation norm is separable if and only if the σ-algebra X is a finite set. Our result is related to fuzzy analysis, functional spaces and discrete mathematics. 相似文献
365.
In this paper we study mixed norm boundedness for fractional integrals related to Laplace–Beltrami operators on compact Riemannian symmetric spaces of rank one. The key point is the analysis of weighted inequalities for fractional integral operators associated to trigonometric Jacobi polynomials expansions. In particular, we find a novel sharp estimate for the Jacobi fractional integral kernel with explicit dependence on the type parameters. 相似文献
366.
Francesco Barioli Wayne Barrett Shaun M. Fallat H. Tracy Hall Leslie Hogben Bryan Shader P. van den Driessche Hein van der Holst 《Journal of Graph Theory》2013,72(2):146-177
Tree‐width, and variants that restrict the allowable tree decompositions, play an important role in the study of graph algorithms and have application to computer science. The zero forcing number is used to study the maximum nullity/minimum rank of the family of symmetric matrices described by a graph. We establish relationships between these parameters, including several Colin de Verdière type parameters, and introduce numerous variations, including the minor monotone floors and ceilings of some of these parameters. This leads to new graph parameters and to new characterizations of existing graph parameters. In particular, tree‐width, largeur d'arborescence, path‐width, and proper path‐width are each characterized in terms of a minor monotone floor of a certain zero forcing parameter defined by a color change rule. 相似文献
367.
Rosalba Di Vincenzo 《Mediterranean Journal of Mathematics》2007,4(1):119-126
Strong solvability in Sobolev spaces is proved for a unilateral boundary value problem for nonlinear parabolic operators.
The operator is assumed to be of Carathéodory type and to satisfy a suitable ellipticity condition; only measurability with
respect to the independent variable X is required.
The main tools of the proof are an estimate for the second derivatives of functions which satisfy the unilateral boundary
conditions and the monotonicity of the operator − u
t
with respect to Δu for the same functions. 相似文献
368.
369.
We give a simple primal algorithm for the generalized maximum flow problem that repeatedly finds and cancels generalized augmenting
paths (GAPs). We use ideas of Wallacher (A generalization of the minimum-mean cycle selection rule in cycle canceling algorithms,
1991) to find GAPs that have a good trade-off between the gain of the GAP and the residual capacity of its arcs; our algorithm
may be viewed as a special case of Wayne’s algorithm for the generalized minimum-cost circulation problem (Wayne in Math Oper
Res 27:445–459, 2002). Most previous algorithms for the generalized maximum flow problem are dual-based; the few previous
primal algorithms (including Wayne in Math Oper Res 27:445–459, 2002) require subroutines to test the feasibility of linear
programs with two variables per inequality (TVPIs). We give an O(mn) time algorithm for finding negative-cost GAPs which can be used in place of the TVPI tester. This yields an algorithm with
O(m log(mB/ε)) iterations of O(mn) time to compute an ε-optimal flow, or O(m
2 log (mB)) iterations to compute an optimal flow, for an overall running time of O(m
3
nlog(mB)). The fastest known running time for this problem is , and is due to Radzik (Theor Comput Sci 312:75–97, 2004), building on earlier work of Goldfarb et al. (Math Oper Res 22:793–802,
1997).
David P. Williamson is supported in part by an IBM Faculty Partnership Award and NSF grant CCF-0514628. 相似文献
370.
We give some expansion formulas and the Kelvin principle for solutions of a class of iterated equations of elliptic type 相似文献