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701.
We study the global and local approaches to the problem of extension of operators into Lindenstrauss spaces.
The research of the first author has been supported in part by DGICYT project MTM2004-02635. 相似文献
702.
703.
Closed formulas in local sensitivity analysis for some classes of linear and non-linear problems 总被引:1,自引:0,他引:1
This paper presents an integrated approach to sensitivity analysis in some linear and non-linear programming problems. Closed
formulas for the sensitivities of the objective function and primal and dual variables with respect to all parameters for
some classes of problems are obtained. As particular cases, the sensitivities with respect to all data values, i.e., cost
coefficients, constraints coefficients and right hand side terms of the constraints are provided for these classes of problems
as closed formulas. The method is illustrated by its application to several examples.
相似文献
704.
Many proteins contain iron as metal ion either within their own structures or bound to their active sites. These iron-containing proteins are involved in numerous biological processes and some of them serve as biomarkers of clinical pathologies, not only related to iron homeostasis but also to other physiological disorders. Thus, a variety of analytical strategies have been developed over the last years in order to conduct studies on Fe-containing proteins. Among them, mass spectrometric (MS) methods still remain as preferred tools since they provide the capabilities of structure elucidation together with quantitative possibilities. Therefore, in this work we have tried to summarize the most recent applications of elemental and molecular mass spectrometric-based methods for the characterization (mostly qualitative but quantitative in some cases) of the high abundant Fe-containing proteins used for clinical diagnosis. 相似文献
705.
706.
H. Calvo del Castillo N. Deprez T. Dupuis F. Mathis A. Deneckere P. Vandenabeele T. Calderón D. Strivay 《Analytical and bioanalytical chemistry》2009,394(4):1043-1058
Differentiation of treated and non-treated gemstones is a chief concern for major jewellery import companies. Low-quality
corundum specimens coming from Asia appear to be often treated with heat, BeO or flux in order to enhance their properties
as precious minerals. A set of corundum samples, rubies and sapphires from different origins, both treated and non-treated
has been analysed at the Centre Européen d’Archéométrie, with ion-beam-induced luminescence (IBIL) and other complementary
techniques such as Raman, proton-induced X-ray emission (PIXE), and proton-induced gamma-ray emission (PIGE). IBIL, also known
as ionoluminescence, has been used before to detect impurities or defects inside synthetic materials and natural minerals;
its use for the discrimination of gemstone simulants or synthetic analogues has been elsewhere discussed (Cavenago-Bignami
Moneta, Gemología, Tomo I Piedras preciosas, perlas, corales, marfil. Ediciones Omega, Barcelona, 1991). PIXE has been frequently
applied in the archaeometric field for material characterisation and provenance studies of minerals (Hughes, Ruby & sapphire.
RWH Publishing, Fallbrook, 1997; Calvo del Castillo et al., Anal Bioanal Chem 387:869–878, 2007; Calligaro et al., NIM-B 189:320–327,
2002) and PIGE complements the elemental analysis by detecting light elements in these materials such as—and lighter than—sodium
that cannot be identified with the PIXE technique (Sanchez et al., NIM-B 130:682–686, 1997; Emmett et al., Gems Gemology 39:84–135,
2003). The micro-Raman technique has also been used complementarily to ion beam analysis techniques for mineral characterisation
(Novak et al., Appl Surf Sci 231–232:917–920, 2004). The aim of this study is to provide new means for systematic analysis
of corundum gemstone-quality mineral, alternative to the traditional gemmologic methods; for this purpose, a Spanish jewellery
import company supplied us with a number of natural corundum samples coming from different places (part of them treated as
explained above). The PIXE elemental concentrations of the samples showed large quantities of calcium and lead in some cases
that can be linked to treatment with fluxes or lead oxide. The plot of the chromium and iron concentration grouped the samples
in various aggregates that corresponded to the different types of corundum analysed. Micro-Raman complemented the PIXE analysis
corroborating the presence of lead oxides but the use of the PIGE technique was not successful for the detection of beryllium
due to the low cross section of the nuclear reaction chosen for its identification. IBIL was capable of distinguishing between
treated and non-treated samples of the same type based on the luminescent features of the materials.
Work presented at the International Symposium on Luminescence Spectrometry 2008, September 7–11, Bologna, Italy 相似文献
707.
V. A. Sadovnichii V. V. Aleksandrov T. B. Aleksandrova R. Vega Castillo Quiróz M. Reyes Romero E. Soto N. E. Shulenina 《Moscow University Mechanics Bulletin》2008,63(6):139-145
A mathematical model for the generation of primary and secondary output information in a gravitoinertial mechanoreceptor is discussed. The numerical results obtained from this model are compared with the results of the physiological experiments performed in the Laboratory of Neurophysiology, Institute of Physiology, Autonomous University of Puebla, Mexico. 相似文献
708.
Let S′ be the class of tempered distributions. For ƒ ∈ S′ we denote by J
−α
ƒ the Bessel potential of ƒ of order α. We prove that if J
−α
ƒ ∈ BMO, then for any λ ∈ (0, 1), J
−α
(f)λ ∈ BMO, where (f)λ = λ−n
f(φ(λ−1)), φ ∈ S. Also, we give necessary and sufficient conditions in order that the Bessel potential of a tempered distribution of order
α > 0 belongs to the VMO space. 相似文献
709.
Marc de la Asunción Luis Castillo Juan Fernández-Olivares Oscar García-Pérez Antonio González Francisco Palao 《Annals of Operations Research》2007,155(1):391-415
An interleaved integration of the planning and scheduling process is presented with the idea of including soft temporal constraints
in a partial order planner that is being used as the core module of an intelligent decision support system for the design
forest fire fighting plans. These soft temporal constraints have been defined through fuzzy sets. This representation allows
us a flexible representation and handling of temporal information. The scheduler model consists of a fuzzy temporal constraints
network whose main goal is the consistency checking of the network associated to each partial order plan. Moreover, we present
a model of estimating this consistency, and show the monitoring and rescheduling capabilities of the system. The resulting
approach is able to tackle problems with ill defined knowledge, to obtain plans that are approximately consistent and to adapt
the execution of plans to unexpected delays.
This work has been partially supported under the project MCyT TIC2002-04146-C05-2 and the contract NET033957 with the Andalusian
Regional Government. 相似文献
710.
In the present paper, the ionic conductivity and the dielectric relaxation properties on the poly(vinyl alcohol)-CF3COONH4 polymer system have been investigated by means of impedance spectroscopy measurements over wide ranges of frequencies and
temperatures. The electrolyte samples were prepared by solution casting technique. The temperature dependence of the sample’s
conductivity was modeled by Arrhenius and Vogel-Tammann-Fulcher (VTF) equations. The highest conductivity of the electrolyte
of 3.41×10 − 3 (Ωcm) − 1 was obtained at 423 K. For these polymer system two relaxation processes are revealed in the frequency range and temperature
interval of the measurements. One is the glass transition relaxation (α-relaxation) of the amorphous region at about 353 K and the other is the relaxation associated with the crystalline region
at about 423 K. Dielectric relaxation has been studied using the complex electric modulus formalism. It has been observed
that the conductivity relaxation in this polymer system is highly non-exponential. From the electric modulus formalism, it
is concluded that the electrical relaxation mechanism is independent of temperature for the two relaxation processes, but
is dependent on composition. 相似文献