Search results for "Modeling and Simulation"
showing 10 items of 1561 documents
NUMERICAL SIMULATION OF MAGNETIC DROPLET DYNAMICS IN A ROTATING FIELD
2013
Dynamics and hysteresis of an elongated droplet under the action of a rotating magnetic field is considered for mathematical modelling. The shape of droplet is found by regularization of the ill-posed initial–boundary value problem for nonlinear partial differential equation (PDE). It is shown that two methods of the regularization – introduction of small viscous bending torques and construction of monotonous continuous functions are equivalent. Their connection with the regularization of the ill-posed reverse problems for the parabolic equation of heat conduction is remarked. Spatial discretization is carried out by the finite difference scheme (FDS). Time evolution of numerical solutions …
Mathematical modelling of an elongated magnetic droplet in a rotating magnetic field
2012
Dynamics of an elongated droplet under the action of a rotating magnetic field is considered by mathematical modelling. The actual shape of a droplet is obtained by solving the initial-boundary value problem of a nonlinear singularly perturbed partial differential equation (PDE). For the discretization in space the finite difference scheme (FDS) is applied. Time evolution of numerical solutions is obtained with MATLAB by solving a large system of ordinary differential equations (ODE).
NICE-MRP: a Near-Optimal Radio-Interference Aware Multi-path Routing Protocol for MANETs
2013
International audience; Nowadays, with the miniaturization of communication devices, dense and highly mobile ad-hoc networks are very common. Besides, more and more devices have several radio interfaces. In such an environment, multi-path routing should be considered. Yet, only few multi-path ad-hoc routing protocols take into account the radio-interferences which might arise between two geographically close routes. Moreover, they generally only forbid the addition of interfering paths rather than looking for a different, more optimized, solution. This paper presents NICE-MRP, a novel multi-path routing protocol for mobile ad-hoc networks giving efficient solutions with respect to physical …
Investigating Potential Alignments between Modelica Standard Library and SAREF Ontologies
2021
International audience; Simulation tools based on the Modelica language provide comprehensive modelling and simulation approaches for building energy systems. However, the simulation and optimisation of such systems are data-driven processes, lacking a common understanding of information structure within the process. This paper investigates the possible semantic alignments of the Smart Appliances REFerence (SAREF) ontology and its extension for building domain, SAREF4BLDG, with the Modelica Standard Library (MSL). Using the MSL, a residential heating system has been modelled in OpenModelica, an open-source modelling and simulation environment. Then, SAREF and its extension SAREF4BLDG semant…
Outside-host phage therapy as a biological control against environmental infectious diseases
2018
Background Environmentally growing pathogens present an increasing threat for human health, wildlife and food production. Treating the hosts with antibiotics or parasitic bacteriophages fail to eliminate diseases that grow also in the outside-host environment. However, bacteriophages could be utilized to suppress the pathogen population sizes in the outside-host environment in order to prevent disease outbreaks. Here, we introduce a novel epidemiological model to assess how the phage infections of the bacterial pathogens affect epidemiological dynamics of the environmentally growing pathogens. We assess whether the phage therapy in the outside-host environment could be utilized as a biologi…
An ontology-based metamodel for multiagent-based simulations
2014
Multiagent-based simulations enable us to validate dierent use-case scenarios in a lot of application domains. The idea is to develop a realistic virtual environment to test particular domain-specic procedures. This paper presents our general framework for interactive multiagent-based simulations in virtual environments. The major contribution of this paper is the integration of the notion of ontology as a core element to the design process of a behavioral simulation. The proposed metamodel describes the concepts of a multiagent simulation using situated agents moving in a semantically enriched 3D environment. The agents perceive the geometric and semantic data in the surrounding environmen…
Dissipative scaling of step-pool features
2021
Abstract This paper focuses on the dissipative similarity of step-pool units at rill, flume and stream scale. This investigation is carried out using recent advances in open channel flow resistance, applications of close-range photogrammetry to rill erosion, available published data on step-pool features in flumes and streams and a new dataset of measurements in fixed bed step-pool rills. A theoretically-based equation for calculating the Darcy-Weisbach friction factor obtained by integration of a power velocity profile is presented. The scale factor Γ of this power velocity profile, which is included in the flow resistance equation, was previously calibrated (Eq. 10) for mobile bed rills w…
Numerical study of the components positioning influence on the stability of a reverse shoulder prosthesis
2014
Aim of this paper is to setup a novel procedure able to analyze performances of a reverse shoulder prosthesis when different geometrical configurations are assumed. Nowadays, such a prosthesis is widely used but, because of its novelty, data in literature give poor information about performances and limits to its applicability. The activity has been divided into the following steps. At the beginning the shape of the prosthesis has been digitally acquired via a 3D scanner. Then, CAD models of all prosthetic components have been geometrically optimized in a way to obtain final entities suitable for numerical simulations. After that, CAD assemblies have been created between prosthetic componen…
Thermoelastic stress analysis by means of an infrared scanner and a two-dimensional fast Fourier transform-based lock-in technique
2008
An infrared thermographic experimental set-up has been proposed and evaluated towards the capability to measure thermoelastic-effect-induced temperature changes. A standard infrared thermocamera with a nominal noise-equivalent temperature difference (NETD) resolution of 0.12 K has been employed to measure the temperature from unidirectional glass-reinforced plastic tensile coupons under cyclic sinusoidal loads. The raster scanning mode of the camera single detector produces a time delay in acquiring the signal from two succeeding pixels on the same row, and from consecutive scanned rows. By exploiting the acquired dwell times, it was possible to produce a periodic pattern on the thermal ma…
Checkpointing Workflows for Fail-Stop Errors
2017
International audience; We consider the problem of orchestrating the exe- cution of workflow applications structured as Directed Acyclic Graphs (DAGs) on parallel computing platforms that are subject to fail-stop failures. The objective is to minimize expected overall execution time, or makespan. A solution to this problem consists of a schedule of the workflow tasks on the available processors and of a decision of which application data to checkpoint to stable storage, so as to mitigate the impact of processor failures. For general DAGs this problem is hopelessly intractable. In fact, given a solution, computing its expected makespan is still a difficult problem. To address this challenge,…