Search results for "Method"
showing 10 items of 13253 documents
Hop: Histogram of patterns for human action representation
2017
This paper presents a novel method for representing actions in terms of multinomial distributions of frequent sequential patterns of different length. Frequent sequential patterns are series of data descriptors that occur many times in the data. This paper proposes to learn a codebook of frequent sequential patterns by means of an apriori-like algorithm, and to represent an action with a Bag-of-Frequent-Sequential-Patterns approach. Preliminary experiments of the proposed method have been conducted for action classification on skeletal data. The method achieves state-of-the-art accuracy value in cross-subject validation.
A new force field including charge directionality for TMAO in aqueous solution
2016
We propose a new force field for trimethylamine N-oxide (TMAO), which is designed to reproduce the long-lived and highly directional hydrogen bond between the TMAO oxygen (OTMAO) atom and surrounding water molecules. Based on the data obtained by ab initio molecular dynamics simulations, we introduce three dummy sites around OTMAO to mimic the OTMAO lone pairs and we migrate the negative charge on the OTMAO to the dummy sites. The force field model developed here improves both structural and dynamical properties of aqueous TMAO solutions. Moreover, it reproduces the experimentally observed dependence of viscosity upon increasing TMAO concentration quantitatively. The simple procedure of the…
Theoretical electronic spectra of 2-aminopurine in vapor and in water
2006
The accurate quantum chemical CASSCF and CASPT2 methods combined with a Monte Carlo procedure to mimic solvation effects have been used in the calculation of the spectroscopic properties of two tautomers of 2-aminopurine (2AP). Absorption and emission spectra have been simulated both in vacuum and in aqueous environment. State and transition energies and properties have been obtained with high accuracy, leading to the assignment of the most important spectroscopic features. The lowest-lying 1 (,*) ( 1 La) state has been determined as responsible for the first band in the absorption spectrum and also for the strong fluorescence observed for the system in water. The combined approach used in …
A quantum mechanics-molecular mechanics study of dissociative electron transfer : The methylchloride radical anion in aqueous solution
2002
The dissociative electron transfer reaction CH3Cl+e−→CH3•+Cl− in aqueous solution is studied by using a QM/MM method. In this work the quantum subsystem (a methylchloride molecule plus an electron) is described using density functional theory while the solvent (300 water molecules) is described using the TIP3P classical potential. By means of molecular dynamics simulations and the thermodynamic integration technique we obtained the potential of mean force (PMF) for the carbon–chlorine bond dissociation of the neutral and radical anion species. Combining these two free energy curves we found a quadratic dependence of the activation free energy on the reaction free energy in agreement with Ma…
Optimization of the sorption process of copper cations from aqueous solution by pine bark (Pinus sylvestris)
2020
This study examined the effect of the chemical modification of pine bark (Pinus sylvestris) on the sorption efficiency of copper cations. The results were interpreted using pseudo-first order and pseudo-second order reaction models as well as Langmuir and Freundlich isothermal models. The sorption experiments were carried out using the batch technique. The study indicated the effect of the competitive sorption of copper cations and hydrogen cations as well as the adverse effect on the sorption efficiency of copper hydroxides formed under alkaline conditions. The need to assess the measurement uncertainty in determining the basic parameters of the sorption process was indicated. It was also …
Calculation of the relative basicities of methylamines in solution
1990
Abstract The relative basicities in solution of the methylamines have been calculated using the model of Miertus, Scrocco and Tomasi to describe the solvent effect. The surface of the cavity is defined with the GEPOL method. The ab initio calculations have been performed using a 4-31G basis set. The relative order is reproduced using a combination of the gas-phase proton affinities obtained with quantum-mechanical methods by Eades, Weil, Dixon and Douglass and the solvation values obtained by us. The results seem to point out that the irregular order is not due to solvent but to basis-set effects.
Arbitrarily shaped plates analysis via Line Element-Less Method (LEM)
2018
Abstract An innovative procedure is introduced for the analysis of arbitrarily shaped thin plates with various boundary conditions and under generic transverse loading conditions. Framed into Line Element-less Method, a truly meshfree method, this novel approach yields the solution in terms of the deflection function in a straightforward manner, without resorting to any discretization, neither in the domain nor on the boundary. Specifically, expressing the deflection function through a series expansion in terms of harmonic polynomials, it is shown that the proposed method requires only the evaluation of line integrals along the boundary parametric equation. Further, minimization of appropri…
Archaeological survey projects in Sicily: issues and best practices from eighties to present time
2017
A partire dagli anni '80 del secolo scorso sono state effettuate numerose indagini archeologiche in Sicilia, in zone dell'isola molto diverse: approcci metodologici, contesti geografici e cronologici, ed infine lo stato dell'edizione, non sempre sono confrontabili tra loro da molti punti di vista Visualizza. Lo scopo di questo lavoro è sia di esaminare questi progetti, prestando attenzione agli aspetti metodologici e di possibili distorsioni interpretative, sia di elaborare buone pratiche utili per nuovi progetti. Since the 80s of the last century several archaeological surveys were carried out in Sicily, in very different areas of the island: methodological approaches, geographical and chr…
GIS applications in archaeology
2011
The diffusion of the use of Geographical Information Systems in archaeology has considerably increased in recent years. This multiplicity of applications is due mainly to the growing interest of archaeologists in modern methodologies for the management of archaeological data, surveyed by topographic, photogrammetric and remote sensing techniques. GIS have become a fundamental tool for managing, sharing, analyzing and visualizing spatially referenced data and they are completely substituting the traditional techniques used by archaeologists, based upon filling out forms, graphics and other paper documents. Besides in the modern global society, dominated by mass media such as Internet, the is…
The role of fire within Neolithic collective burials: Spatial analyses of cremains from the site of La Truie Pendue, France
2016
International audience; The use of collective graves is one of the main features of the western European Late Neolithic. A single gravesite received the successive deposition of dozens or sometimes hundreds of individuals. While cremations or even full-fired inhumation layers are often found within these funerary deposits, the actual role of fire is still poorly understood. Recently discovered within the important archaeological complex of Passy (Yonne, France), the burned collective grave of La Truie-Pendue provides an outstanding case study to examine the use of fire within Neolithic funerary rites. In this study, we develop a new contextual approach to bone alterations in order to recons…