Les terres agricoles ont été durablement contaminées à la fois par les pesticides mis à la disposition des agriculteurs pour lutter contre les charançons et autres insectes nuisibles, et par les engrais azotées pour augmenter la productivité chez les plantes.Des recherches récentes concernent des cultures alternatives écologiques utilisant les plantes de service qui fournissent les nutriments aux plantes principales. Ce travail de thèse s'inscrit dans cette perspective, d'un point de vue modélisation.L'accent est mis sur la résolution de problèmes de contrôle du phénomène d'absorption de nutriments, par les racines dans la rhizosphère (partie proche des racines), en considérant les deux cas de sols : sol sain et sol pollué.Ces phénomènes d'absorption sont modélisés par des systèmes d'advection-diffusion de type Nye-Tinker-Barber (NTB). La concentration de nutriments absorbée, solution du problème, est une fonction du temps et de l'espace.On étudie l'existence de solution du système NTB dans les deux cas où la fonction d'absorption de nutriments à la frontière (surface de la racine) appelée fonction de Michealis-Menten, est linéaire et/ou non linéaire, à l’aide des outils d’analyse fonctionnelle. On étudie ensuite les problèmes de contrôle optimal associés au système NTB, en considérant les deux cas linéaire et non linéaire, en application pour les deux cas d’absorption de nutriments en sol non pollué puis en sol pollué. Pour le premier cas, on utilise les techniques classiques de recherche d'un contrôle pour les systèmes distribués, tandis que, pour le second cas, on fait appel aux notions de contrôle sans regret et contrôle à moindres regrets de J.-L. Lions. Les contrôles obtenus pour les différents problèmes sont caractérisés chacun par un système d'optimalité (SO) cas sans pollution, et système d’optimalité singulier (SOS) dans le cas avec pollution.= / Agriculture soils were highly contaminated for a long time by pesticides which were widely used by producers to fight against weevils. Soils where also contaminated by the use of fertilizers to increase the plant development. An ecological alternative using service plants is encouraged following recent research. The aim of this work is to give a mathematical and a modelling point of view as we study the mecha- nisms of nutrient transfer to plants using the mathematical analysis and optimal control theories. The two cases of polluted and non-polluted soils are considered. The nutrient transfer and uptake processes are modeled by an advection-diffusion system derived from the Nye-Tinker-Barber (NTB) model. The absorbed nutrient concentration represented by the Michaelis-Mention function at the root surface of the principal plant, depends on time and space. We study the existence of a solution for the linear and nonlinear NTB systems, then we characterize the opti- mal control which corresponds to the added nutrients from the service plant. For the pollution case, we use the concept of low-regret and no-regret control of J.-L. Lions.

Abstract not available

This BC Digitization Survey Results presentation was one of several presentations delivered at the BC Digitization Symposium 2008 held on December 1 & 2, 2008. For more information, please visit the BC Digitization Symposium 2008 website at: http://symposium.westbeyondthewest.ca.

INTRODUCTION While the concept is widely defined and interpreted, all Web 2.0 tools have certain characteristics in common; they are collaborative in nature, interactive, and dynamic. The Science and Engineering librarians at the University of British Columbia are collaborating with their liaison departments to record science and engineering podcasts, host them and share them with a wider audience. OBJECTIVES In this session, we discuss the use of podcasting as an outreach tool that connects a large academic science and engineering library with its users and raises users’ awareness of additional library services. Functionality, usability and practical applications of podcasting tools are reviewed. OUTCOMES At the end of this session, we will have demonstrated: 1) Overall usability of podcasting academic science and engineering content; tips and tricks when creating and tailoring podcasts to your community needs; 2) Use of podcasting as an outreach and community engagement tool in academic libraries and as a supplement for the traditional academic information resources. DISCUSSION The strength of podcasting, to allow content to be created by the users for the users, makes it an appealing addition to the academic librarians’ toolbox. Podcasting is a service that many of our users might not expect from their library, which makes it a unique and attractive offering. It requires few resources, and the end result might exceed librarians’ expectations. We found podcasting to be a robust outreach tool and a service that raises the profile of the library and as such creates an opportunity for users to find additional library resources. Nevertheless, it is necessary for academic librarians to critically evaluate the continuous innovations of Web 2.0 technologies on an ongoing basis so that they are best prepared to put them into the appropriate context amongst other relevant and important information.

This article, written by Glenn Drexhage, Communications Officer – UBC Library/Irving K. Barber Learning Centre, appeared in the BCLA Browser: Linking the Library Landscape online newsletter (vol.1, no.1 2009). For more information, please visit the BC Digitization Symposium 2008 website at: http://symposium.westbeyondthewest.ca and the BCLA Browser website at: http://bclabrowser.ca.

Developing  a part of project documentation for a multifunctional house is the main subject of my thesis.This particular object is planned for a constructional lot in a district of Hodonín. Building has  four levels,  is separately standing, made of brick and does not have any cellar.  First floor is intended for  business and service use. Second, third and fourth floor are designed for living. There are one-room, two-room and four-room flats. Multifunctional house is made of  calcium silicate blocks and will be covered with flat roof.