Comparison of some probabilistic methods for analyzing slope stability problem

Abstract The study aims at comparing the results of different probabilistic methods such as the perturbation method, Spectral Stochastic Finite Element Method (SSFEM

The Olive Mills Waste Water (OMW) as an Organic Amendment for Controlling Wind Erosion in Southern Tunisia by Improving the Soil Surface Structure

Abstract: Spraying OMW on poor sandy soils in the olive orchards induces increasing of the organic matter content, the formation of aggregates and improving the soil structure stability. Hence, OMW can be an alternative and effective way to control this polluting sewage. Since 1995 a field experiment is running in an olive plot in chammakh-Zarzis, south Tunisia, where rates of 50, 100 and 200 m 3 of OMW were sprayed yearly on 1 ha fields with 16 olives trees per ha. Data collected in 2006 showed an increase in organic matter content from originally 0.06 to 1.27 %, an increase in the amount of aggregates > 2 mm to 34%, and an increase in the threshold friction velocity for deflation to 12 m sec -1 for the 200 m 3 ha -1 application

Pore-scale Modeling of Viscous Flow and Induced Forces in Dense Sphere Packings

We propose a method for effectively upscaling incompressible viscous flow in large random polydispersed sphere packings: the emphasis of this method is on the determination of the forces applied on the solid particles by the fluid. Pore bodies and their connections are defined locally through a regular Delaunay triangulation of the packings. Viscous flow equations are upscaled at the pore level, and approximated with a finite volume numerical scheme. We compare numerical simulations of the proposed method to detailed finite element (FEM) simulations of the Stokes equations for assemblies of 8 to 200 spheres. A good agreement is found both in terms of forces exerted on the solid particles and effective permeability coefficients

Le tourisme saharien au sud-est tunisien, menace ou vecteur de développement durable des zones marginales

International audienc

Le tourisme saharien au sud-est tunisien, menace ou vecteur de développement durable des zones marginales

International audienc

La valorisation du patrimoine et nouvelles alternatives pour un développement local durable dans le Sud-est tunisien

International audienceThe enhancement of local heritage can pave the way to the economic, social and environmental development of land-locked regions. Such an option becomes an alternative for local development. The South-east is one of the less favoured and underprivileged areas of Tunisia, facing several difficulties to keep up with the current development trends, but characterized by a very rich local heritage. The innovation and promotion of this local heritage by the tourism industry, the multifunctionality of agriculture and the organisation of local players can provide a solution to support the development of this territory.La valorisation du patrimoine est un vecteur de développement local des territoires enclavés aussi bien sur le plan économique et social qu'environnemental. Cette mesure devient une alternative de développement. La région sud-est tunisienne est l'une des zones défavorisées de la Tunisie, confrontée à plusieurs difficultés pour suivre le mode de développement, mais caractérisée par une richesse locale très abondante. L'innovation et la valorisation touristique de cette richesse locale, la multifonctionnalité de l'agriculture locale et l'organisation des acteurs locaux sont une solution pour le développement de ce territoire

Vibrations of Circular Plates with Elastically Restrained Edge against Translation and Resting on Elastic Foundation

The present paper deals with exact solutions for the free vibration characteristics of thin circular plates elastically restrained against translation and resting on Winkler-type elastic foundation based on the classical plate theory. Parametric investigations are carried out for estimating the influence of edge restraint against translation and stiffness of the elastic foundation on the natural frequencies of circular plates. The elastic edge restraint against translation and the presence of elastic foundation has been found to have a profound influence on vibration characteristics of the circular plate undergoing free transverse vibrations. Computations are carried out for natural frequencies of vibrations for varying values of translational stiffness ratio and stiffness parameter of Winkler-type foundation. Results are presented for twelve modes of vibration both in tabular and graphical form for use in design. Extensive data is tabulated so that pertinent conclusions can be arrived at on the influence of translational edge restraint and the foundation stiffness ratio of the Winkler foundation on the natural frequencies of uniform isotropic circular plates

Instability and Pattern Formation in Three-Species Food Chain Model via Holling Type II Functional Response on a Circular Domain

This paper is devoted to the study of food chain predator–prey model. This model is given by a reaction–diffusion system defined on a circular spatial domain, which includes three-state variables namely, prey and intermediate predator and top predator and incorporates the Holling type II and a modified Leslie–Gower functional response. The aim of this paper is to investigate theoretically and numerically the asymptotic behavior of the interior equilibrium of the model. The local and global stabilities of the positive steady-state solution and the conditions that enable the occurrence of Hopf bifurcation and Turing instability in the circular spatial domain are proved. In the end, we carry out numerical simulations to illustrate how biological processes can affect spatiotemporal pattern formation in a disc spatial domain and different types of spatial patterns with respect to different time steps and diffusion coefficients are obtained

LC-DAD/ESI-MS/MS characterization of phenolic constituents in Tunisian extra-virgin olive oils: Effect of olive leaves addition on chemical composition

PubMedID: 28964371The aim of the present research is to evaluate the chemical characterization of main compounds from Tunisian monocultivar extra virgin olive oil (EVOO) (‘Chemlali’, ‘Chétoui’, ‘Zalmati’ and ‘crossbreeding Chemlali by Zalmati’) extracted after the addition of different amounts (0% and 3%) of olive leaves. As expected for extra virgin olive oil, the main sterols found in all analyzed samples were ß-sitosterol, ?-5-avenasterol, campesterol and clerosterol. Stigmasterol, 24-methylene-cholesterol, cholesterol, campestanol, sitostanol, ?-7-stigmastenol, ?-5,24-stigmastadienol, and ?-7-avenasterol were also found in all samples, but in lower amounts. Most of these compounds were significantly affected by the cultivars but not to be affected by added leaves at 3% to olives prior to the extraction process. The obtained results revealed that 14 phenolic compounds belonging to different phenolic types were characterized and quantified by an effective HPLC-DAD-ESI-MS/MS method. In all the studied olive oil samples, dialdehydic form of elenolic acid linked to hydroxytyrosol (3,4-DHPEA-EDA), oleuropein aglycon (3,4-DHPEA-EA), and ligstroside aglycon (p-HPEA-EA) were the most abundant compounds. In addition, EVOO from ‘Chétoui’ cultivar extracted with 3% of olive leaves presented the highest amount of individual phenolic compounds. © 2016 Elsevier Lt