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51.
In this paper we establish the stability of Ritz procedure in sense of Michlin and Tucker for a class of nonlinear two-point boundary value problems which has been considered by Varga, Schultz and Ciarlet in [1].  相似文献   
52.
The F(-), Cl(-), and Br(-) binding selectivity of bis(p-nitroanilide)s of dipicolinic and isophthalic acids was studied by using competitive electrospray mass spectrometry and UV-Visible spectroscopy. Both hosts prefer binding Cl(-) over either F(-) or Br(-). Host deprotonation was observed to some extent in all experiments in which the host was exposed to halide ions. When F(-) was present, host deprotonation was often the major process, whereas little deprotonation was observed by Cl(-) or Br(-), which preferred complexation. A solution of either host changed color when mixed with a F(-), H(2)PO(4)(-), di- or triphenylacetate solution.  相似文献   
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Visual analytics is the science of analytical reasoning facilitated by interactive visual interfaces. In this paper, we present an adaptation of the visual analytics framework to the context of software understanding for maintenance. We discuss the similarities and differences of the general visual analytics context with the software maintenance context, and present in detail an instance of a visual software analytics application for the build optimization of large-scale code bases. Our application combines and adapts several data mining and information visualization techniques in answering several questions that help developers in assessing and reducing the build cost of such code bases by means of user-driven, interactive analysis techniques.  相似文献   
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In this paper, by using some of our new results concerning the shift space for an infinite IFS (see A. Mihail and R. Miculescu, The shift space for an infinite iterated function system, Math. Rep. Bucur. 11 (2009), 21?C32), we show that, for an infinite set A, the embedded version of the Lipscomb space L(A) in l p (A), ${p \in [1,\infty)}$ , with the metric induced from l p (A), denoted by ${\omega_p^A}$ , is the attractor of an infinite iterated function system comprising affine transformations of l p (A). In this way we provide a generalization of the positive answer that we gave to an open problem of J.C. Perry (see Lipscomb??s universal space is the attractor of an infinite iterated function system, Proc. Amer. Math. Soc. 124 (1996), 2479?C2489) in one of our previous works (see R. Miculescu and A. Mihail, Lipscomb space ?? A is the attractor of an infinite IFS containing affine transformations of l 2(A), Proc. Amer. Math. Soc. 136 (2008), 587?C592). Moreover, as a byproduct, we provide a generalization of Corollary 15 from Perry??s paper by proving that ${\omega_p^A}$ is a closed subset of l p (A).  相似文献   
58.
Summary LetX⊂P 3 be an irreducible smooth curve which is not a complete intersection. The main result of this paper shows that whenX is an a.c.i. of special type, i.e. its homogeneous ideal is generated by three polynomial of the same degreem, and additionallym>2, the subbundles of maximal degree of the normal bundle ofX inP 3 correspond to the singular points of maximal multiplicity of a plane curve which is the image ofX by a map (the linear system of the surfaces of minimal degree throughX). In particular this normal bundle is stable. The initial case of this family of curves, i.e. form=3, has been studied by E. Ballico-Ph. Ellia with different methods.
Riassunto SiaX⊂P 3 una curva irriducibile e liscia che non è una completa intersezione. Il risultato principale di questa Nota mostra che quandoX è una almost completa intersezione di tipo speciale, cioè il suo ideale omogeneo è generato minimamente da 3 polinomi dello stesso gradom, e, inoltre,m>2, i sottofibrati di grado massimo del fibrato normale diX inP 3 corrispondono ai punti singolari di molteplicità massima di una curva piana che è l’immagine diX tramite una mappa (il sistema lineare delle superficie di grado minimo passanti perX). In particolare questo fibrato normale è stabile. Il caso iniziale di questa famiglia di curve, i.e. perm=3, è stato studiato da E. Ballico-Ph. Ellia con differenti metodi.


This research is supported by GNSAGA (Italy).

The main results of this paper have been the object of a talk at the meeting on ?Curves in Projective Space? held at Rocca di Papa in june 1985.  相似文献   
59.
We prove a bifurcation result for a perturbed sublinear elliptic problem defined on a compact Riemannian manifold without boundary. This result is then applied to a singular elliptic problem on even-dimensional Euclidean spaces.  相似文献   
60.
We provide bounds for the absolute discrepancy of sequences of fractions with denominators streaming in a given arithmetic progression and satisfying divisibility constraints. Supported by the CERES Program 4-147/2004 of the Romanian Ministry of Education and Research.  相似文献   
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