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341.
Versatile variable temperature insert at the DEIMOS beamline for in situ electrical transport measurements
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L. Joly B. Muller E. Sternitzky J.-G. Faullumel A. Boulard E. Otero F. Choueikani J.-P. Kappler M. Studniarek M. Bowen P. Ohresser 《Journal of synchrotron radiation》2016,23(3):652-657
The design and the first experiments are described of a versatile cryogenic insert used for its electrical transport capabilities. The insert is designed for the cryomagnet installed on the DEIMOS beamline at the SOLEIL synchrotron dedicated to magnetic characterizations through X‐ray absorption spectroscopy (XAS) measurements. This development was spurred by the multifunctional properties of novel materials such as multiferroics, in which, for example, the magnetic and electrical orders are intertwined and may be probed using XAS. The insert thus enables XAS to in situ probe this interplay. The implementation of redundant wiring and careful shielding also enables studies on operating electronic devices. Measurements on magnetic tunnel junctions illustrate the potential of the equipment toward XAS studies of in operando electronic devices. 相似文献
342.
In this paper, we derive the probability distribution function of the first entry time in a time varying subset of the phase space of a non-homogeneous semi-Markov chain. Deterministic and stochastic time varying subsets are considered and results with a ready algorithmic implementation are provided. A possible application is debated by defining and analysing deterministic and stochastic time variable level crossing order for semi-Markov chains. 相似文献
343.
We show that every additively representable comparative probability order on n atoms is determined by at least n–1 binary subset comparisons. We show that there are many orders of this kind, not just the lexicographic order. These results
provide answers to two questions of Fishburn et al. (Math. Oper. Res. 27:227–243, 2002). We also study the flip relation on the class of all comparative probability orders introduced by Maclagan. We generalise
an important theorem of Fishburn, Pekeč and Reeds, by showing that in any minimal set of comparisons that determine a comparative
probability order, all comparisons are flippable. By calculating the characteristics of the flip relation for n=6 we discover that the polytopes associated with the regions in the corresponding hyperplane arrangement can have no more
than 13 facets and that there are 20 regions whose associated polytopes have 13 facets. All the neighbours of the 20 comparative
probability orders which correspond to those regions are representable.
Research partially supported by the N.Z. Centres of Research Excellence Fund (grant UOA 201). 相似文献
344.
The scale change model in survival analysis incorporates unobserved heterogeneity through a frailty that enters the baseline hazard function to change the time scale. In this paper we examine the stochastic properties of the mixtures of scale change model and build dependence between the overall population variable and the frailty variable. We also carry out stochastic comparisons between overall population variables when their respective frailty or baseline variables are ordered in the sense of various stochastic orders. Finally, we demonstrate how the variation of the baseline variable has an effect on the model. 相似文献
345.
346.
We consider the strongly nonlinear boundary value problem,
where A is an elliptic operator of finite or infinite order. We introduce anisotropic weighted Sobolev spaces and we show under a
certain sign condition of the Carathéodory function g without assuming any growth restrictions, the existence of the weak solutions.
相似文献
347.
The fractional weak discrepancywdF(P) of a poset P=(V,?) was introduced in [A. Shuchat, R. Shull, A. Trenk, The fractional weak discrepancy of a partially ordered set, Discrete Applied Mathematics 155 (2007) 2227-2235] as the minimum nonnegative k for which there exists a function satisfying (i) if a?b then f(a)+1≤f(b) and (ii) if a∥b then |f(a)−f(b)|≤k. In this paper we generalize results in [A. Shuchat, R. Shull, A. Trenk, Range of the fractional weak discrepancy function, ORDER 23 (2006) 51-63; A. Shuchat, R. Shull, A. Trenk, Fractional weak discrepancy of posets and certain forbidden configurations, in: S.J. Brams, W.V. Gehrlein, F.S. Roberts (Eds.), The Mathematics of Preference, Choice, and Order: Essays in Honor of Peter C. Fishburn, Springer, New York, 2009, pp. 291-302] on the range of the wdF function for semiorders (interval orders with no induced ) to interval orders with no , where n≥3. In particular, we prove that the range for such posets P is the set of rationals that can be written as r/s, where 0≤s−1≤r<(n−2)s. If wdF(P)=r/s and P has an optimal forcing cycle C with and , then r≤(n−2)(s−1). Moreover when s≥2, for each r satisfying s−1≤r≤(n−2)(s−1) there is an interval order having such an optimal forcing cycle and containing no. 相似文献
348.
For a finite group G, let ψ(G) denote the sum of element orders of G. It is known that the maximum value of ψ on the set of groups of order n, where n is a positive integer, will occur at the cyclic group ? n . In this paper, we investigate groups with the second largest value of ψ on the set of groups of the same order. 相似文献
349.
It is well-known that if R is a left Noetherian ring, then there is a bijective correspondence between minimal prime ideals of R and maximal torsion radicals of R-Mod. Using the notion of a prime M-ideal, it is shown that this correspondence can be extended to the category σ[M] of modules subgenerated by a module M, provided that M is a Noetherian quasi-projective generator in σ[M]. Furthermore, under this hypothesis the prime M-ideals are the fully invariant submodules P of M such that M/P is semi-compressible. 相似文献
350.
C.R. Johnson 《Linear and Multilinear Algebra》2013,61(10):1403-1420