Search results for "Formula"

New data on the mercury antimony mineral shakhovite: Chemical composition, unit cell and crystal structure

1982

A new investigation of the mercury antimony mineral shakhovite yielded space groupIm witha=4.871(1),b=15.098(3),c=5,433(1) A and β=98.86(2)°. The determination of the crystal structure gave a cell content of Hg8Sb2O12. Since the presence of Hg2-groups indicates that shakhovite is a pure Hg(1) compound and the infrared spectrum shows an absorption band at 3440 cm−1 which is due to the OH-stretching frequency, it is assumed that there are six oxygen atoms and six OH-groups in the unit cell. Thus the chemical formula of shakhovite reads Hg4Sb(OH)3O3 with two formula units per unit cell. The Hg−Hg distance in the Hg2-group is 2.543 A, each mercury atom has a close oxygen neighbour at 2.160 and …

P-adic Henstock integral in the problem of representation of functions by multiplicative transforms

2005

We introduce a path integral of Henstock type and use it to obtain inversion formulas for multiplicative integral transformations. The problem considered is a generalization of the problem of reconstruction of coefficients of a convergent orthogonal series from its sum.

Kombinatorā optimizācija ar dziļajiem neironu tīkliem

2022

Kombinatorās optimizācijas problēmām ir liela praktiskā nozīme, tomēr tās, parasti, ir NP-grūtas un to risināšana ir apgrūtināta. Darba mērķis ir noskaidrot, vai dziļo neironu tīklu metodes var tikt pielietotas kombinatorai optimizācijai. Kā reprezentatīvas problēmas tiek izvēlētas Būla formulas apmierināšana (SAT) un jauktu veselu skaitļu programmēšana (MILP). Abām problēmām tiek izveidotas specializētas ziņu pārsūtīšanas grafu neironu tīklu arhitektūras, kas papildinātas ar autora piedāvātu vaicājumu mehānismu. Tīklu apmācība tiek veikta ar darbā piedāvātām nepārraudzītās mašīnmācīšanās zaudējumu funkcijām (nav nepieciešams risinājumu). Piedāvātais neironu tīklu risinātājs SAT problēmai p…

Insights into Kelvin probe force microscopy data of insulator-supported molecules

2015

We present a detailed analysis and understanding of Kelvin probe force microscopy (KPFM) data for a system of point charges in a vacuum-dielectric tip-sample system. Explicit formulae describing the KPFM signal $\ensuremath{\Delta}V$ are derived for the two KPFM operation modes, namely amplitude modulation and frequency modulation (FM). The formulae allow for a physical interpretation of the resulting KPFM signal, reveal contributing parameters, and especially disclose an additive behavior. We numerically evaluate these equations and show exemplary KPFM slice data for a single point charge. The theoretical analysis is complemented by two-dimensional FM-KPFM maps obtained experimentally on 2…

Induced smoothing in LASSO regression

The thesis is being carried out with the National research Council at the Institute of Biomedicine and Molecular Immunology "Alberto Monroy" of Palermo, where I am a fellow, under the supervision of MD Stefania La Grutta. Our research unit is focused on clinical research in allergic respiratory problems in children. In particular, we are interested in to assess the determinants of impaired lung function in a sample of outpatient asthmatic children aged between 5 and 17 years enrolled from 2011 to 2017. Our dataset is composed by n = 529 children and several covariates regarding host and environmental factors. This thesis focuses on hypothesis testing in lasso regression, when one is interes…

Experimental Evidence of Leaks in Elastic Pipes

2016

Several studies have been carried out in recent decades to establish a relationship between total head and leaks. In literature, the leakage governing equations have been analysed in light of pipe materials, water head, leak dimension or shape. Most of these contributions questioned the classical Torricelli equation, demonstrating through experimental evidence that the classical orifice law can give unsatisfactory results. Nevertheless, starting from the Torricelli equation, other exponential or linear governing equations have been proposed as mathematical models able to reproduce the leakages in water distribution systems (WDSs). To investigate the validity of the proposed governing equati…

Durability of calcarenitic hypogea in the underground cultural heritage of Palermo (Sicily)

2011

The paper deals with the stability conditions of hypogea, several hundred m 2 wide, dating from the Punic period to the XIX century, dug out of the calcarenitic table that makes up the bedrock of the Plain of Palermo in the Fossa della Garofala. This work concerns the influence that the shape of the hypogea and the characteristics of the lithotypes wields on the instability and decay phenomena taking place, by mean of laboratory tests on the calcarenite and parametric numerical models. The comparison between the numerical models and the actual instability phenomena validated the use of the empirical formula of Hoeck to the mechanical characterization of complex structured rock-mass in soft …

Zero Viscosity Limit for Analytic Solutions, of the Navier-Stokes Equation on a Half-Space.¶I. Existence for Euler and Prandtl Equations

1998

This is the first of two papers on the zero-viscosity limit for the incompressible Navier-Stokes equations in a half-space. In this paper we prove short time existence theorems for the Euler and Prandtl equations with analytic initial data in either two or three spatial dimensions. The main technical tool in this analysis is the abstract Cauchy-Kowalewski theorem. For the Euler equations, the projection method is used in the primitive variables, to which the Cauchy-Kowalewski theorem is directly applicable. For the Prandtl equations, Cauchy-Kowalewski is applicable once the diffusion operator in the vertical direction is inverted.

Zero Viscosity Limit for Analytic Solutions of the Navier-Stokes Equation on a Half-Space.¶ II. Construction of the Navier-Stokes Solution

1998

This is the second of two papers on the zero-viscosity limit for the incompressible Navier-Stokes equations in a half-space in either 2D or 3D. Under the assumption of analytic initial data, we construct solutions of Navier-Stokes for a short time which is independent of the viscosity. The Navier-Stokes solution is constructed through a composite asymptotic expansion involving the solutions of the Euler and Prandtl equations, which were constructed in the first paper, plus an error term. This shows that the Navier-Stokes solution goes to an Euler solution outside a boundary layer and to a solution of the Prandtl equations within the boundary layer. The error term is written as a sum of firs…

Leksinių samplaikų sąrašo tikslinimas: bandymas taikyti "Formulex" metodą

2016

Svetimkalbių vartotojų produkuojamos kalbos tekstynai pastaruoju metu neretai tiriami aprašant leksines samplaikas, t. y. pasikartojančias tam tikro ilgio žodžių sekas, jų vartojimą bei funkcijas. Tokiuose tyrimuose neišvengiamai susiduriama su iš dalies sutampančiomis ar nepilnos struktūros samplaikomis. Pavyzdžiui, keturžodės anglų kalbos samplaikos at the same time, the same time it ir but at the same yra automatiškai generuojamos kompiuterio programa kaip tekstyne pasikartojančios sekos. Tačiau ar kiekviena jų laikytina tikrąja samplaika? Ar kiekvienai iš jų galima priskirti vienokią ar kitokią funkciją? Šiame straipsnyje siekiama parodyti, kaip „Formulex” metodas (Forsyth, 2015a, 2015b…