4,937 Works

Auto-ajustement de régulateurs PID robustes dans le domaine fréquentiel

Daniel Garcia
This work considers the adjustment of proportional-integral-derivative (PID) controllers. Because of their very simple structures, this kind of controllers are very appreciated, and used abundantly by the industrial community. The restricted number of the controller parameters often implies moderate performances, compared to those that can be obtained by high order control structures. In compensation, it is highly desired to use simple and fast procedures for the tuning of PID controllers. In practice, the methods using...

Pôles de développement économique et logistique d'entreprise

Aymeric Sevestre
Economic development policies such as the Enterprise Zone have been pursued with different designs by state and local governments in many countries. These programs can be defined by a double objective: to promote and control economic growth. This thesis investigates the compatibility of these public policies with the location strategies of the private companies based on their logistical needs. The first step of this research gives a global view on the key elements of the...

The effect of liberalisation on incumbent's innovation:the case of the postal sector

Cátia Alexandra Pereira Felisberto
The network industries have been undergoing a process of reform, where liberalisation is one of the main features. This thesis studies the effect of liberalisation, with and without competition, on the incumbent's incentives to innovate. A model of incumbent network operator is developed and analysed when the incumbent is a monopolist, as well as when it faces an entrant. The objectives of the incumbent are specified in a general manner to allow for revenue, profit,...

Diversification into logistics:strategies for incumbent postal operators in Europe

Patrick Mollet
Postal incumbents in Europe have encountered during the last decade fundamental changes in their industry environment, which now threaten their very business model: governments decided to liberalise first the parcel market, then gradually the letter market so as to introduce competition. Substitution by electronic means led at the same time to a decline in mail volume. As a consequence, incumbent operators are losing market share in a declining market, whereas new revenue streams would be...

Strategic options of energy service companies in competitive energy markets

Gustave Nguene
In this dissertation, I determine the strategic options of energy service companies active in urban areas. This work is developed considering the wider EU policy framework, namely a liberalised energy market, environmental protection and security of supply. This framework has created a competitive environment favouring the emergence of a new type of actors, including providers of energy service (ESCOs) competing to increase their market shares. I refer to energy service companies as companies that can...

Co-opetition: strategy and performance of firms in standard setting organizations:the case of the postal sector

Farah Abdallah
Co-opetition is a new field of business and of thinking. It occurs when companies collaborate joining their efforts for creating new value, while maintaining their rivalries, aspiring to outperform the other firms in the network. This new perspective advocates companies to create new business strategies and develop new capabilities that deal with the paradoxical behaviors of collaboration and competition simultaneously. The purpose of this dissertation is to investigate the motivation of competing companies to pursue...

Reform and risk management in the urban water sector:the role of regulation

Patrícia Alves Luís Manso
Traditionally, urban water services were characterised by local monopolies, where the incumbent was publicly-owned. This was explained by safety, health, economic, and technological reasons related to the sector's specificities. However, in spite of this, the sector has undergone important reforms in recent years, triggered by efficiency, underinvestment, and environmental problems. The most important features of reform are competitive pressures, private sector participation, and more autonomous operators. These reforms have created a new environment for urban...

On the structural stability of the free and metal-loaded c-terminal domain of the prion protein

Maria Carola Colombo
A misfolded conformer of the cellular prion protein, denoted as scrapie prion protein, is considered responsible for a variety of fatal neurodegenerative diseases. Both, the function of the protein in its native conformation as well as the factors that trigger the protein misfolding and its mechanism remain as yet open issues. The aim of this thesis is to give a contribution to answering these questions by means of a variety of tools currently available in...

Adeno-Associated Virus-Mediated Gene Delivery for the Treatment of Amyotrophic Lateral Sclerosis and other Motor Neuron Disorders

Christopher Towne
The delivery of molecules and genes to the central nervous system (CNS) poses a major challenge for the treatment of neurodegenerative diseases. CNS disorders require long-term intervention and the presence of the blood-brain barrier (BBB) restricts the penetration of conventional drugs to the desired target cells. One approach towards stable delivery of therapeutic agents to the CNS is based on the transfer of DNA to target cells using viral vectors; a strategy known as gene...

Miniaturized analytical systems for mass spectrometry-based protein studies

Mélanie Abonnenc
Current proteomic strategies depend strongly on the development of analytical methodologies and instrumentation. In parallel to the development of mass spectrometry (MS) - based proteomic workflows, microfluidic devices emerged in this field as a flexible tool for rapid and sensitive protein studies. In this context, the present work focuses on the development of miniaturized analytical systems for protein studies, especially by electrospray ionization mass spectrometric detection. Several approaches have been proposed to complement the mass...

Mechanisms of degradation of concrete by external sulfate ions under laboratory and field conditions

Aude Chabrelie
The durability of concrete is a major challenge for the construction, which devotes one third to one half of its annual investment to building maintenance. The lack of field data regarding concrete durability, especially in the case of exposure to sulfate ions ("sulfate attack") makes it difficult to determine the appropriate test methods and performance criteria. Additionally, the increased use of blended concretes (cement with mineral admixtures) suffers from a lack of experience regarding their...

Iterative geometric design for architecture

Ivo Stotz
This work investigates on computer aided integrated architectural design and production. The aim is to provide integral solutions for the design and the production of geometrically complex free-form architecture. Investigations on computer aided geometric design and integrated manufacturing are carried out with equal importance. This research is considering an integral and interdisciplinary approach, including computer science, mathematics and architecture. Inspired by fractal geometry, the IFS formalism is studied with regards to discrete architectural geometric design....

Scanning Near-Field Optical Microscopy Study of Biomolecules, Elaboration of New SNOM Probes and Detection Methods

Mounir Mensi
The combination of the topographic resolution of Scanning Probe Microscopy with the subwavelength information of light/matter interaction leads to a new instrument called Scanning Near-field Optical Microscope (SNOM). This new instrument is an ideal tool to study physico-chemical properties of nano-sized objects. Most of the biomolecular processes require exactly the spatial resolution of SNOM. However, to routinely achieve a nanometric scale topographic and optical resolution, further improvements of the technique are needed. These improvements concern...

Resonant spectroscopy on strongly correlated materials

Xiaoqiang Wang
All strongly correlated materials exhibit fascinating physical properties, like Mott insulator transitions, high temperature superconductivity, Kondo and heavy fermion behavior, colossal magnetoresistance, etc. These properties make them attractive for developing novel applications. To achieve this ambitious goal, the nature of the strong electronic correlations must be investigated. Soft x-ray resonant inelastic scattering (RIXS) and resonant inverse photoemission (RIPES) are precious in this context, because they provide detailed information on the fundamental low energy excitations. The...

Orbitally shaken bioreactors for mammalian cell culture:engineering characterization and bioprocess scale-up

Xiaowei Zhang
Driven by the commercial success of recombinant biopharmaceuticals, there is an increasing demand for novel, cost-effective mammalian cell culture bioreactor systems for the production of biologicals requiring mammalian protein processing. Recently, orbitally shaken bioreactors at scales from a few mLs to 2'000-L have been explored for the cultivation of mammalian cells and are considered to be attractive alternatives to conventional stirred-tank bioreactors because of increased flexibility and reduced costs. Although the choice of geometry of...

Stabilization strategies for discontinuous Galerkin methods

Benjamin Stamm
The subject of this thesis is the analysis of discontinuous Galerkin methods for linear partial differential equations of first or second order. Discontinuous Galerkin methods are known to satisfy a local mass conservation property. Taking a closer look one can observe that this property often depends on the method itself, i.e. on some method-dependent parameters. The main objective of this work is to design discontinuous Galerkin schemes satisfying a method-independent local mass conservation property still...

Polarisation reversal in ferroelectric PVDF and PZT films

Roman Gysel
Ferroelectrics are characterised by a spontaneous polarisation that can be reversed by an external electric field. The stability of the polarisation states and the possibility for controlled switching between the states render ferroelectric materials very attractive for memory applications, in which polarisation states are associated to a binary information "0" or "1". Fast, dense, and reliable data storage has gained enormous importance in our information technology based society. In this context, the fundamental physics of...

Interactive Surfaces Based on Polymer Brushes

Dusko Paripovic
While the bulk structure of a material determines its mechanical properties, its surface plays a key role when interactions with the environment are important. Nowadays materials in bio- and nanotechnology are required to possess very complex functionalities and to interact specifically to the stimuli they receive from their surroundings. Thus, their surface modifications are becoming very demanding. In recent years surface initiated controlled radical polymerization techniques have emerged as very versatile strategies that provide a...

Beam-Machine Interaction Studies for the Phase II LHC Collimation System

Luisella Lari
Collimation is essential in a high Energy and Intensity hadron collider with SuperConducting magnets, like the LHC at CERN. To improve the cleaning efficiency and to reduce the LHC impedance budget in stable condition and at top Energy, additional 30 Phase II collimators are foreseen to be installed. The work of this PhD analyses the beam-machine interactions in the LHC Betatron Cleaning Insertions for its upgrade with the Phase II collimators. These studies aim at...

Quality embedded intelligent remanufacturing

Young Seok Kim
This thesis is motivated from the four keywords: remanufacturing, quality, multi-agent and intelligence. Recent years' environmental problems caused tightening the regulations and legislations for used products. Therefore remanufacturing is getting more attention. The quality of used products is uncertain and even dynamically changes during the remanufacturing process, and each used product should be individually handled in a different way depending on its quality. Fortunately recent developing wireless technologies like radio frequency identification (RFID) may enable...

La densification des espaces urbains, une problématique contemporaine interrogée par le logement collectif

Frédéric Frank
The modern and contemporary city has given birth to vast peripheries due to rapid growth. A first glance at these areas reveals that architectural theories and urbanism paradigms encounter each other without fixed rules or regulated planning. Moreover, these sectors located close to city centers are often still considered as lifeless and without interest, even by building professionals, despite an intense debate on the topic since the 1960's. Nevertheless, it seems appropriate to explore in...

Experimental investigation of unstrained diffusion flames and their instabilities

Etienne Robert
In this thesis, thermal-diffusive instabilities are studied experimentally in diffusion flames. The novel species injector of a recently developed research burner, consisting of an array of hypodermic needles, which allows to produce quasi one-dimensional unstrained diffusion flames has been improved. It is used in a new symmetric design with fuel and oxidizer injected through needle arrays which allows to independently choose both the magnitude and direction of the bulk flow through the flame. A simplified...

Registration Year

  • 2010

Resource Types

  • Text

Data Centers

  • EPFL Infoscience