Endovascular treatment of acute aortic isthmian ruptures: case study

Traumatic rupture of the aortic isthmus is a rare lesion occurring in patients subjected to violent deceleration. Because of the forces involved, it is frequently associated with concomitant life-threatening injuries. The endovascular intervention has been described to be a feasible and efficient technique which may be proposed as a therapeutic option for patients with multiple traumas instead of delayed classical surgical repair after stabilization. We report the case of an adult who has had an accident with a traumatic rupture of the aortic isthmus associated with other lesions, our patient received endovascular treatment. The aortic prosthesis was imported from France and the surgery was done 3 days after the patient's admission. This procedure was performed for the first time in Morocco in our hospital with a multidisciplinary team. The prosthesis was implemented successfully and the result was very satisfactory on the heart level.Keywords: Endovascular treatment, aortic isthmian ruptures, endovascular prosthesi

Adaptivni estimator brzine za bezsenzorsko vektorsko upravljanje asinkronim motorom zasnovan na umjetnoj neuronskoj mreži

This paper presents an adaptive speed observer for an induction motor using an artificial neural network with a direct field-oriented control drive. The speed and rotor flux are estimated with the only assumption that from stator voltages and currents are measurable. The estimation algorithm uses a state observer combined with an intelligent adaptive mechanism based on a recurrent neural network (RNN) to estimate rotor speed. The stator and rotor resistances are estimated by a simple Proportional-Integrator (PI) controller, which reduces sensitivity to variations, due essentially to the influence of temperature. The proposed sensorless control scheme is tested for various operating conditions of the induction motor drive. Experimental results demonstrate a good robustness against load torque disturbances, the estimated fluxes and rotor speed converge to their true values, which guarantees that a precise trajectory tracking with the prescribed dynamics.Ovaj članak opisuje adaptivni estimator brzine temeljen na umjetnoj neuronskoj mreži, koji se primijenjuje na asinkroni motor pogonjen izravnim vektorskim upravljanjem. Brzina i magnetski tok rotora estimiraju se uz pretpostavku dostupnosti mjerenja napona i struja statora. Algoritam koristi estimator stanja u kombinaciji s inteligentnim adaptivnim mehanizmom temeljenim na povratnoj neuronskoj mreži (RNN) kako bi se estimirala brzina rotora. Otpori statora i rotora estimiraju se jednostavnim Proporcionalno-Integralnim (PI) regulatorom, čime se smanjuje osjetljivost na varijacije uzrokovane utjecajem temperature. Predložena bezsenzorska upravljačka shema testirana je za različite radne uvjete asinkronog motora. Eksperimentalni rezultati pokazuju visoki stupanj robusnosti s obzirom na poremećaj momenta tereta, a estimirani tokovi i brzina rotora konvergiraju prema stvarnim vrijednostima što garantira precizno praćenje trajektorija uz zahtijevanu dinamiku

Elliptic systems at resonance for jumping non-linearities

In this article, we study the existence of nontrivial solutions for the problem \displaylines{ -\Delta u=\alpha _1u^{+}-\beta _1u^{-}+f(x,u,v)+h_1( x) \quad \text{in }\Omega, \cr -\Delta v=\alpha _2v^{+}-\beta _2v^{-}+g(x,u,v)+h_2( x) \quad \text{in }\Omega, \cr u=v=0\quad \text{on }\partial \Omega, } where $\Omega$ is a bounded domain in $\mathbb{R}^{N}$, and $h_1,h_2\in L^2( \Omega)$. Here $[ \alpha_j,\beta _j] \cap \sigma(-\Delta)={\lambda}$, where $\sigma(\cdot)$ is the spectrum. We use the Leray-Schauder degree theory

Comprendre le travail dans les “métiers adressés à autrui”

Dans ce numéro 16-1 de la revue Activités nous publions six articles, un dossier dont le titre est « Comprendre le travail dans les métiers ‘adressés à autrui’ » et, enfin, deux recensions d’ouvrage. Dans l'éditorial nous annonçons la prochaine journée d'étude dont le thème est "Espaces et temps de l'activité à l'ère de la digitalisation". Nous vous souhaitons une bonne lecture

Abstracts of 1st International Conference on Computational & Applied Physics

This book contains the abstracts of the papers presented at the International Conference on Computational & Applied Physics (ICCAP’2021) Organized by the Surfaces, Interfaces and Thin Films Laboratory (LASICOM), Department of Physics, Faculty of Science, University Saad Dahleb Blida 1, Algeria, held on 26–28 September 2021. The Conference had a variety of Plenary Lectures, Oral sessions, and E-Poster Presentations. Conference Title: 1st International Conference on Computational & Applied PhysicsConference Acronym: ICCAP’2021Conference Date: 26–28 September 2021Conference Location: Online (Virtual Conference)Conference Organizer: Surfaces, Interfaces, and Thin Films Laboratory (LASICOM), Department of Physics, Faculty of Science, University Saad Dahleb Blida 1, Algeria