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101.
We present a novel solution algorithm for 3D parameter identification based on low frequency electromagnetic data. With focus on large-scale applications such as monitoring of subsea oil production, CO2 sequestration, and geothermal systems, the proposed solution algorithm is designed to meet challenges related to low parameter sensitivity, nonuniqueness of the inverse solutions, nonlinearity in the mapping from the data to the parameter space, and costly numerical simulations. Motivated by earlier investigations on the relation between sensitivity, nonlinearity and scale, the proposed solution approach is based on a reduced, composite parameter representation. Though a reduced representation restricts the solution space, flexibility with respect to which parameter functions that can be represented is obtained by facilitating the estimation of the structure and smoothness of the representation itself. Moreover, the resolution of the parameter function is detached from the computational grid and determined as part of the estimation. The performance of the proposed solution algorithm is illustrated through numerical examples for identification of underground electric conductivity changes from time-lapse electromagnetic observations. 相似文献
102.
An optical technique for slope detection by using as storing medium a photorefractive BSO crystal is proposed. The technique relays in that a local tilt produced in a diffusing reflective surface can be mapped as a speckle transversal shifting in a plane perpendicular to the optical axis. The volume nature of the storing medium is quite adequate to highlight the speckle volume nature and its associated properties. Experimental results obtained by using a rubber vibrating membrane are presented. 相似文献
103.
Jeffrey Colin Morton 《Applied Categorical Structures》2011,19(4):659-707
This paper describes a relationship between essentially finite groupoids and two-vector spaces. In particular, we show to
construct two-vector spaces of Vect-valued presheaves on such groupoids. We define two-linear maps corresponding to functors between groupoids in both a covariant and contravariant
way, which are ambidextrous adjoints. This is used to construct a representation—a weak functor—from Span(FinGpd) (the bicategory of essentially finite groupoids and spans of groupoids) into 2Vect. In this paper we prove this and give the construction in detail. 相似文献
104.
Lorien J. Parker Louis C. Italiano Craig J. Morton Nancy C. Hancock David B. Ascher Jade B. Aitken Hugh H. Harris Pablo Campomanes Ursula Rothlisberger Anastasia De Luca Mario Lo Bello Wee Han Ang Paul J. Dyson Michael W. Parker 《Chemistry (Weinheim an der Bergstrasse, Germany)》2011,17(28):7705-7705
105.
Fabrizio Davì Morton E. Gurtin 《Zeitschrift für Angewandte Mathematik und Physik (ZAMP)》1990,41(6):782-811
Mullins, in a series of papers, developed a surface dynamics for phase interfaces whose evolution is controlled by mass diffusion within the interface. It is our purpose here to embed Mullins's theory within a general framework based on balance laws for mass and capillary forces in conjunction with a version of the second law, appropriate to a purely mechanical theory, which asserts that the rate at which the free energy increases cannot be greater than the energy inflow plus the power supplied. We develop an appropriate constitutive theory, and deduce general and approximate equations for the evolution of the interface.
Sommario Mullins, in una serie di articoli inerenti la morfologia delle superfici di interfaccia tra fasi, ha sviluppato una dinamica delle superfici la cui evoluzione è governata dal fenomeno di diffusione di massa all'interno dell'interfaccia. Scopo di questo articolo è inscrire la teoria di Mullins in uno schema più generale basato su leggi di bilancio della massa e delle azioni capillari nonchè su una formulazione puramente meccanica del secondo principio della termodinamica, asserente ehe l'incremento di energia libera non possa essere superiore al flusso di energia ed alla potenza fornite all'interfaccia. Viene successivamente sviluppata una appropriata teoria costitutiva, e vengono dedotte le equazioni di evoluzione sia in forma generale che approssimata.相似文献
106.
J. Stan Morton James B. Westmoreland April Rhineheart 《Journal of Radioanalytical and Nuclear Chemistry》2009,282(2):483-486
Tritiated water is probably the most mobile manmade nuclide found in the environment. The low-energy beta decay produces few
health concerns except at extremely high concentrations of tritium. However, because of the ubiquitous nature of tritiated
water, when identified in the bionetwork, it can be viewed as a precursor of nuclides with greater health risks. For this
reason alone it becomes desirable to determine tritium concentrations many orders of magnitude below that considered a health
concern. A devise is described that eliminates the need for large water-filled chest freezers used as coolers. The enrichment
cells can be employed individually or in series. 相似文献
107.
Morton E. Gurtin 《Zeitschrift für Angewandte Mathematik und Physik (ZAMP)》1991,42(3):370-388
This paper discusses the formulation of balance laws for mass, force, and energy in conjunction with a law of entropy growth for the motion of a sharp evolving phase interface within a continuum framework.
Zusammenfassung In dieser Arbeit werden Erhaltungssätze für Masse, Kraft und Energie sowie eine Entropieungleichung für die räumliche Ausbreitung einer scharfen Phasengrenzschicht im Rahmen eines kontinuierlichen Modells diskutiert.相似文献
108.
S. Yu. Kun D. J. Hinde M. Dasgupta J. R. Leigh J. C. Mein C. R. Morton J. O. Newton B. A. Robson H. Timmers A. V. Vagov 《Zeitschrift für Physik A Hadrons and Nuclei》1997,359(3):263-270
Excitation functions for the strongly dissipative collision 19 F(E lab = 135–140 MeV)+89 Y with an energy step of 250 keV in the lab. system have been measured. The data are consistent with previous measurements and exhibit oscillations, which are interpreted as an indication of quantum chaotic phenomena in dissipative heavy-ion collisions. The Fourier component of the energy autocorrelation of the total projectile-like angle-integrated dissipative yield has been calculated and is found to have a pulsing behaviour with a time interval between sequential pulses equal to the period of the coherent nuclear rotation. This provides another possibility of experimentally detecting quantum chaos in dissipative heavy-ion collisions. 相似文献
109.
Josefina Alvarez Martha Guzmn-Partida 《Journal of Mathematical Analysis and Applications》2002,270(2):235-434
We characterize those tempered distributions which are S′-convolvable with a given class of singular convolution kernels. We study both, the Euclidean case and the product domain case. In the Euclidean case, we consider a class of kernels that includes Riesz kernels, Calderón–Zygmund singular convolution kernels, finite part distributions defined by hypersingular convolution kernels, and Hörmander multipliers. In the product domain case, we consider a class of singular kernels introduced by Fefferman and Stein as a generalization of the n-dimensional Hilbert kernel. 相似文献
110.
Alejandro Pisanty Carlos Amador Yosadara Ruiz Martha de la Vega 《Zeitschrift für Physik B Condensed Matter》1990,80(2):237-239
The results of self-consistent, spin-polarized LMTO band structure calculations are shown for the compounds Ni3Pt and NiPt3, ofL12 (Cu3Au) structure. Lattice constants are reported together with bulk moduli, and the electronic structure is studied in relation to magnetism in both cubic compounds. Covalent magnetism is shown to act against the magnetization in Ni3Pt. 相似文献