Design and performance evaluation of a state-space based AQM

Recent research has shown the link between congestion control in communication networks and feedback control system. In this paper, the design of an active queue management (AQM) which can be viewed as a controller, is considered. Based on a state space representation of a linearized fluid flow model of TCP, the AQM design is converted to a state feedback synthesis problem for time delay systems. Finally, an example extracted from the literature and simulations via a network simulator NS (under cross traffic conditions) support our study

Robust control tools for traffic monitoring in TCP/AQM networks

Several studies have considered control theory tools for traffic control in communication networks, as for example the congestion control issue in IP (Internet Protocol) routers. In this paper, we propose to design a linear observer for time-delay systems to address the traffic monitoring issue in TCP/AQM (Transmission Control Protocol/Active Queue Management) networks. Due to several propagation delays and the queueing delay, the set TCP/AQM is modeled as a multiple delayed system of a particular form. Hence, appropriate robust control tools as quadratic separation are adopted to construct a delay dependent observer for TCP flows estimation. Note that, the developed mechanism enables also the anomaly detection issue for a class of DoS (Denial of Service) attacks. At last, simulations via the network simulator NS-2 and an emulation experiment validate the proposed methodology

Moms Support Group: Lack of Support to Moms Postpartum

This service learning project is centered on organizing and running a mom support group regularly to provide moms with the chance to assist one another in a safe atmosphere for their recovery following childbirth. Additionally, I created a social media page on the platform found on Instagram for this support group so that moms may communicate frequently and follow and interact to join for upcoming events. The project will benefit the moms by helping them make more meaningful connections and feel more supported during this time. Navigating parenting while maintaining all aspects of your life can be difficult. Going through similar experiences and getting assistance from others has proven helpful

20 ans de comparaison France-Allemagne : de l'effet sociétal à l'analyse de l'articulation des régulations globales et locales

International audienceNous proposons de mettre au centre de la comparaison internationale les niveaux de décision et en particulier leur articulation. Cela suppose d'abandonner les visions stéréotypées qui rangent d'emblée les faits observés, soit du côté des régulations globales (sociétales ou autres) soit du côté des décisions locales. Il s'agit en effet de renoncer aux explications " totalisantes ". L'objet de la comparaison devient l'analyse des interdépendances entre décisions locales et globales. L'exemple de la négociation du temps de travail montre comment les différents niveaux de décisions interagissent. La loi définit certes le cadre des négociations, mais ce cadre est ensuite retravaillé au niveau de la branche, et au niveau de l'entreprise. La France et l'Allemagne se distinguent alors non seulement par l'existence de régulations globales différentes, aboutissant d'un côté à des lois et de l'autre côté à des conventions collectives, mais aussi par des articulations différentes des régulations globales et locales.Malgré les différences, il nous semble alors que la question de l'emploi et sa traduction en différents types de régulations intermédiaires, permettent de relancer le débat sur la convergence de ces deux sociétés

Dynamics of plasma blobs in a shear flow

The global dynamic of plasma blobs in a shear flow is investigated in a simple magnetized torus using the spatial Fourier harmonics (k-space) framework. Direct experimental evidence of a linear drift in k space of the density fluctuation energy synchronized with blob events is presented. During this drift, an increase of the fluctuation energy and a production of the kinetic energy associated with blobs are observed. The energy source of the blob is analyzed using an advection-dissipation-type equation that includes blob-flow exchange energy, linear drift in k space, nonlinear processes, and viscous dissipations. We show that blobs tap their energy from the dominant E B vertical background flow during the linear drift stage. The exchange of energy is unidirectional as there is no evidence that blobs return energy to the flow

Utilisation d'un algorithme d'interpolation de données irrégulièrement réparties pour l'estimation et la compensation de mouvement dans une séquence d'images

Dans ce papier, nous présentons une nouvelle modélisation du mouvement. Cette modélisation est issue d'une technique d'interpolation à partir d'échantillons irréguliers. Elle permet à partir d'un nombre limité de vecteur-échantillons de construire un champ dense de vecteurs. L'optimisation des paramètres liés aux vecteur-échantillons conduit à un champ dense de vecteurs minimisant l'erreur de compensation. Des résultats en terme de qualité de compensation en mouvement et en terme de codage sont donnés

On Designing Lyapunov-Krasovskii Based AQM for Routers Supporting TCP Flows

For the last few years, we assist to a growing interest of designing AQM (Active Queue Management) using control theory. In this paper, we focus on the synthesis of an AQM based on the Lyapunov theory for time delay systems. With the help of a recently developed Lyapunov-Krasovskii functional and using a state space representation of a linearized fluid model of TCP, two robust AQMs stabilizing the TCP model are constructed. Notice that our results are constructive and the synthesis problem is reduced to a convex optimization scheme expressed in terms of linear matrix inequalities (LMIs). Finally, an example extracted from the literature and simulations via {\it NS simulator} support our study

Floating polygon soup

International audienceThis paper presents a new representation called floating polygon soup for applications like 3DTV and FTV (Free Viewpoint Television). This representation is based on 3D polygons and takes as input MVD data. It extends the previously proposed polygon soup representation which is appropriate for both compression, transmission and rendering stages. The floating polygon soup conserves these advantages while also taking into account misalignments at the view synthesis stage due to modeling errors. The idea for reducing these misalignments is to morph the 3D geometry depending on the current viewpoint. Results show that artifacts in virtual views are reduced and objective quality is increased