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21.
Danilo Santos Cruz Joo M. de Araújo Carlos A. N. da Costa Carlos C. N. da Silva 《Entropy (Basel, Switzerland)》2021,23(5)
Full waveform inversion is an advantageous technique for obtaining high-resolution subsurface information. In the petroleum industry, mainly in reservoir characterisation, it is common to use information from wells as previous information to decrease the ambiguity of the obtained results. For this, we propose adding a relative entropy term to the formalism of the full waveform inversion. In this context, entropy will be just a nomenclature for regularisation and will have the role of helping the converge to the global minimum. The application of entropy in inverse problems usually involves formulating the problem, so that it is possible to use statistical concepts. To avoid this step, we propose a deterministic application to the full waveform inversion. We will discuss some aspects of relative entropy and show three different ways of using them to add prior information through entropy in the inverse problem. We use a dynamic weighting scheme to add prior information through entropy. The idea is that the prior information can help to find the path of the global minimum at the beginning of the inversion process. In all cases, the prior information can be incorporated very quickly into the full waveform inversion and lead the inversion to the desired solution. When we include the logarithmic weighting that constitutes entropy to the inverse problem, we will suppress the low-intensity ripples and sharpen the point events. Thus, the addition of entropy relative to full waveform inversion can provide a result with better resolution. In regions where salt is present in the BP 2004 model, we obtained a significant improvement by adding prior information through the relative entropy for synthetic data. We will show that the prior information added through entropy in full-waveform inversion formalism will prove to be a way to avoid local minimums. 相似文献
22.
Being nondestructive and requiring short measurement times, a low amount of material, and no sample preparation, Raman spectroscopy
is used for routine investigation in the study of gemstone inclusions and treatments and for the characterization of mounted
gems. In this work, a review of the use of laboratory Raman and micro-Raman spectrometers and of portable Raman systems in
the gemology field is given, focusing on gem identification and on the evaluation of the composition, provenance, and genesis
of gems. Many examples are shown of the use of Raman spectroscopy as a tool for the identification of imitations, synthetic
gems, and enhancement treatments in natural gemstones. Some recent developments are described, with particular attention being
given to the semiprecious stone jade and to two important organic materials used in jewelry, i.e., pearls and corals. 相似文献
23.
Danilo Sciarrone Luisa Schipilliti Carla Ragonese Peter Quinto Tranchida Paola Dugo Giovanni Dugo Luigi Mondello 《Journal of chromatography. A》2010,1217(7):1101-1105
The present research is focused on the determination of the enantiomeric distribution of chiral compounds, contained in mandarin essential oils, by means of conventional chiral gas chromatography with flame ionization detection (enantio-GC-FID); the results attained were compared with those derived from heart-cutting multidimensional GC-mass spectrometry (MDGC/MS), to evaluate the reliability of the monodimensional technique as a tool for quality control. The Deans-switch MDGC system was equipped with two GC ovens, which were connected via a heated transfer line, a flame ionization detector (FID1) in the first dimension and a quadrupole MS as second-dimension detector. The a priori knowledge of potential co-elutions concerning target compounds (an enantiomer and an interfering compound), when using enantio-GC-FID, could enable the use of corrected enantiomer excess values. Correction factors could be calculated through a preliminary GC-FID analysis (using an apolar column), considering the peak areas of the known interferences. The method used for the calculation of a so-called “coelution correction factor” is described, along with some examples. 相似文献
24.
ángel Ballesteros Alberto Enciso Francisco J. Herranz Orlando Ragnisco Danilo Riglioni 《International Journal of Theoretical Physics》2011,50(7):2268-2277
We consider the classical superintegrable Hamiltonian system given by
_boxclose=+= + ,\mathcal{H}_{\lambda}=\mathcal{T}+\mathcal{U}=\frac{\mathbf{p}^2}{2(1+{\lambda}\mathbf{q}^2)} + \frac{ \omega^2\mathbf{q}^2}{2(1+{\lambda}\mathbf{q}^2)}, 相似文献
25.
Danilo Babusci Giuseppe Dattoli Dario Sacchetti 《Central European Journal of Physics》2011,9(6):1381-1386
The Airy transform is an ideally suited tool to treat problems in classical and quantum optics. Even though the relevant mathematical
aspects have been thoroughly investigated, the possibilities it offers are wide and some features, such as the link with special
functions and polynomials, still contain unexplored aspects. In this note we will show that the so called Airy polynomials
are essentially the third order Hermite polynomials. We will also prove that this identification opens the possibility of
developing new conjectures on the properties of this family of polynomials. 相似文献
26.
In this paper, a family of interpolation neural network operators are introduced. Here, ramp functions as well as sigmoidal functions generated by central B-splines are considered as activation functions. The interpolation properties of these operators are proved, together with a uniform approximation theorem with order, for continuous functions defined on bounded intervals. The relations with the theory of neural networks and with the theory of the generalized sampling operators are discussed. 相似文献
27.
Danilo šuster 《Acta Analytica》2004,19(33):45-54
Modal arguments for incompatibility of freedom and determinism are typically based on the “transfer principle” for inability
to act otherwise (Beta). The principle of agglomerativity (closure under conjunction introduction) is derivable from Beta.
The most convincing counterexample to Beta is based on the denial of Agglomeration. The defender of the modal argument has
two ways to block counterexamples to Beta: (i) use a notion of inability to act otherwise which is immune to the counterexample
to agglomerativity; (ii) replace Beta with a logically stronger principle Beta 2. I argue that the second strategy fails because
the strengthened principle and Agglomeration together entail Beta. So this strategy makes sense only if Beta 2 is applied
without Agglomeration. But if Beta 2 is used without Agglomeration, then the incompatibilist will undercut the rationale for
the premise of his argument. I illustrate this point with the analysis of Warfield (1996) and his use of Beta 2 in the so
called direct argument for incompatibilism. 相似文献
28.
The equations governing the response of hysteretic systems to sinusoidal forces, which are memory dependent in the classical phase space, can be given as a vector field over a suitable phase space with increased dimension. Hence, the stationary response can be studied with the aids of classical tools of nonlinear dynamics, as for example the Poincaré map. The particular system studied in the paper, based on hysteretic Masing rules, allows the reduction of the dimension of the phase space and the implementation of efficient algorithms. The paper summarises results on one degree of freedom systems and concentrates on a two degree of freedom system as the prototype of many degree of freedom systems. This system has been chosen to be in 1:3 internal resonance situation. Depending on the energy dissipation of the elements restoring force, the response may be more or less complex. The periodic response, described by frequency response curves for various levels of excitation intensity, is highly complex. The coupling produces a strong modification of the response around the first mode resonance, whereas it is negligible around the second mode. Quasi-periodic motion starts bifurcating for sufficiently high values of the excitation intensity; windows of periodic motions are embedded in the dominion of the quasi-periodic motion, as consequence of a locking frequency phenomenon. 相似文献
29.
Saoussen Hammami Ridha El Mokni Khaled Faidi Danilo Falconieri Alessandra Piras Silvia Procedda 《Natural product research》2015,29(24):2336-2340
The objectives of this study were to chemically characterise and evaluate the antioxidant potential of the essential oil from Teucrium flavum L. subsp. flavum growing spontaneously in Tunisia. The volatile oil was extracted by hydrodistillation of the aerial parts in a Clevenger type apparatus. Forty constituents were identified via GC and GC-MS analysis. β-caryophyllene (32.5%) and α-humulene (17.8%) were the most abundant components. The evaluation of free radical scavenging activity using stable DPPH free radical showed that the volatile oil exhibits a moderate antioxidant activity and reduces DPPH to 50% at EC50 value of 1230 μg mL? 1. 相似文献
30.
The law of virtual work (VWL) is probably the first law in the history of mechanics; it is previous to the one on the lever, though not completely distinct from it. Here I will discuss the logical status of VWL, that is whether it is an autonomous principle or a theorem of some sort of mechanics. The problem is complicated by the fact that up to now no universally recognised expression has been accepted for it. From this article the problematical nature of VWL demonstrability is quite clear when the mechanics does not characterise completely the constraints. Italian schools in the XVIII century, even if we do not take Lagrange into consideration, had an important role, both in the development of VWL and in the discussion of its role. 相似文献
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