ParisTech

About: ParisTech is a education organization based out in Paris, France. It is known for research contribution in the topics: Finite element method & Residual stress. The organization has 1888 authors who have published 1965 publications receiving 55532 citations. The organization is also known as: Paris Institute of Technology & ParisTech Développement.

Robust Nonlinear Controls of Model-Scale Helicopters Under Lateral and Vertical Wind Gusts

Abstract: A helicopter maneuvers naturally in an environment where the execution of the task can easily be affected by atmospheric turbulence, which leads to variations of its model parameters. This paper discusses the nature of the disturbances acting on the helicopter and proposes an approach to counter the effects. The disturbance consists of vertical and lateral wind gusts. A 7-degrees-of-freedom (DOF) nonlinear Lagrangian model with unknown disturbances is used. The model presents quite interesting control challenges due to nonlinearities, aerodynamic forces, under actuation, and its non-minimum phase dynamics. Two approaches of robust control are compared via simulations with a Tiny CP3 helicopter model: an approximate feedback linearization and an active disturbance rejection control using the approximate feedback linearization procedure. Several simulations show that adding an observer can compensate the effect of disturbances. The proposed controller has been tested in a real-time application to control the yaw angular displacement of a Tiny CP3 mini-helicopter mounted on an experiment platform.

Ocarina: An Environment for AADL Models Analysis and Automatic Code Generation for High Integrity Applications

Abstract: Developing safety-critical distributed applications is a difficult challenge. A failure may cause important damages as loss of human life or mission's failure. Such distributed applications must be designed and built with rigor. Reducing the tedious and error-prone development steps is required; we claim that automatic code generation is a natural solution. In order to ease the process of verification and certification, the user can use modeling languages to describe application critical aspects. In this paper we introduce the use of AST as a modeling language for Distributed Real-time Embedded (DRE) systems. Then we present our tool-suite ocarina which allows automatic code generation from AST models. Finally, we present a comparison between ocarina and traditional approaches.

Development of silver nanoparticle loaded antibacterial polymer mesh using plasma polymerization process.

Abstract: Plasma polymerized polyacrylic acid (PPAA) was deposited on a polymer substrate, namely polyethylene terephthalate (PET) mesh, for entrapment of silver nanoparticle (Ag-NP) in order to achieve antibacterial property to the material. Carboxylic groups of PPAA act as anchor as well as capping and stabilizing agents for Ag-NPs synthesized by chemical reduction method using NaBH4 as a reducing agent. Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy (XPS), and water contact angle analysis were used to characterize the PPAA coatings. The Ag-NPs loaded polymer samples were characterized by UV–visible spectroscopy, field emission scanning electron microscopy, energy dispersive X-ray, and XPS techniques. XPS analysis showed ∼1.0 at.% loading of Ag-NPs on to the PPAA-PET-mesh, which was composed of 79% zero-valent (Ag°) and 21% oxidized nano-Ag (Ag+). The plasma processed PET meshes samples were tested for antibacterial activity against two bacterial strains, namely Staphylococcus aureus (Gram positive) and Escherichia coli (Gram negative). Qualitative and quantitative tests showed that silver containing PPAA-PET meshes exhibit excellent antibacterial property against the tested bacteria with percent reduction of bacterial concentration >99%, compared to the untreated PET mesh. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2013.

Experimental Data and Predictions of Dissociation Conditions for Ethane and Propane Simple Hydrates in the Presence of Methanol, Ethylene Glycol, and Triethylene Glycol Aqueous Solutions

Abstract: Experimental dissociation data for ethane and propane simple hydrates in the presence of (0.05 and 0.15) mass fractions of methanol, ethylene glycol, and triethylene glycol aqueous solutions are reported in this work. The experimental data have been measured using an isochoric method. All the experimental data are compared with the predictions of a general correlation (HWHYD correlation) and a thermodynamic model (HWHYD model). The agreements between the experimental and predicted data are generally found acceptable.