4,937 Works

Semantics for virtual humans

Alejandra Garcia Rojas Martinez
Population of Virtual Worlds with Virtual Humans is increasing rapidly by people who want to create a virtual life parallel to the real one (i.e. Second Life). The evolution of technology is smoothly providing the necessary elements to increase realism within these virtual worlds by creating believable Virtual Humans. However, creating the amount of resources needed to succeed this believability is a difficult task, mainly because of the complexity of the creation process of Virtual...

Wafer-Scale Fabrication of Thin SiN Membranes and Au Films and Membranes with Arrays of Sub-um Holes Using Nanosphere Lithography

Mona Julia Katharina Klein
In this thesis, the wafer-scale fabrication of SiN membranes, Au films and Au membranes with arrays of sub-µm holes is described. Two conceptually different processes (1) and (2) were developed, both of which are based on nanosphere lithography (NSL) with self-assembled close-packed monolayers of polystyrene (PS) beads. PS beads with a diameter D in the range of 420 nm to 530 nm were used. The hole array periodicity p was thus determined by D. Different...

Measurements and Monte Carlo calculations with the extended-range Bonner sphere spectrometer at high-energy mixed fields

Evangelia Dimovasili
The use of spectrometry to provide information for neutron radiation protection has become an increasingly important activity over recent years. The need for spectral data arises because neither area survey instruments nor personal dosimeters give the correct dose equivalent results at all neutron energies. It is important therefore to know the spectra of the fields in which these devices are used. One of the systems most commonly employed in neutron spectrometry and dosimetry is the...

Neuron models of the generic bifurcation type:network analysis and data modeling

Enno De Lange
Minimal nonlinear dynamic neuron models of the generic bifurcation type may provide the middle way between the detailed models favored by experimentalists and the simplified threshold and rate model of computational neuroscientists. This thesis investigates to which extent generic bifurcation type models grasp the essential dynamical features that may turn out play a role in cooperative neural behavior. The thesis considers two neuron models, of increasing complexity, and one model of synaptic interactions. The FitzHugh-Nagumo...

Commissioning scenarios and tests for the LHC collimation system

Chiara Bracco
The physics reach of the LHC requires unprecedented luminosity and beam intensity in proton-proton collisions. The maximum intensity in the LHC is directly coupled to the maximum peak beam loss rate and the cleaning efficiency from the collimation system. A sophisticated LHC collimation system is implemented in two cleaning insertions and in the experimental areas. In a first phase 88 collimators are installed, being controlled by 344 stepping motors in total. The work of this...

Three topics in parallel communications

Emin Gabrielyan
The main objectives pursued by parallelism in communications are network capacity enhancement and fault-tolerance. Efficiently enhancing the capacity of a network by parallel communications is a non-trivial task. Some applications may also allow one to split the sources and destinations into multiple sources and destinations. An example is parallel Input/Output (I/O). Parallel I/O requires scalability, high throughput and good load balance. Low granularity enables good load balance but tends to reduce throughput. In this thesis...

Emergent Dynamics in Neocortical Microcircuits

Rodrigo De Campos Perin
Interactions among neurons can take place in a wide variety of forms. It is the goal of this thesis to investigate the properties and implications of a number of these interactions that we believe are relevant for information processing in the brain. Neuroscience has progressed considerably in identifying the diverse neuronal cell-types and providing detailed information about their individual morphological, genetic and electrophysiological properties. It remains a great challenge to identify how this diversity of...

An early separation scheme for the LHC luminosity upgrade

Guido Sterbini
In this thesis we evaluate the potential of the Early Separation Scheme for the Luminosity Upgrade of the Large Hadron Collider (LHC). The main goal of the Early Separation Scheme is to reduce the crossing angle between the proton beams at the collision point in order to increase the luminosity performance of the machine and to alleviate, at the same time, the detrimental effects due to the electromagnetic interaction between the beams. The Early Separation...

Impact de la communication voco-visuelle dans le management sur la motivation des collaborateurs

Catherine Monnin
Our research work wishes to highlight the importance of the relationship between the vocal and physical behaviour of the manager and team motivation. In order to investigate this important relationship, a survey by means of a questionnaire and two field studies were undertaken. The survey has notably showed that in communication situations the working population questioned is above all sensitive to physical behaviour. The people questioned often put vocal communication in second place. It should...

Open source corporate strategy (OSCS):unveiling the firm's open sources of competitive advantage

Juan Andrei Villarroel Fernández
This doctoral dissertation defines and sheds light on a nascent phenomenon in management, informally referred to as "crowdsourcing". I term this concept Open Source Corporate Strategy, or OSCS, which borrows insights from the open source innovation literature, as well as from the strategy literature. This new concept explains how the firm may incorporate open source principles into its business model, as an effective diversification strategy to gain and sustain competitive advantage, in the context of...

Organic pollutants in Swiss compost and digestate

Rahel Christine Brändli
Composting (aerobic treatment of organic wastes) and digestion (anaerobic treatment of organic wastes combined with biogas production) are important waste management strategies with increasing significance in the European Union and Switzerland. Most of the compost produced is applied to agricultural soils, which hereby recycles nutrients and influences soil properties beneficially. However, compost can contain pollutants that may be hazardous for the soil ecosystem. The problem related to heavy metals had been recognised and measures for...

Occurrence of persistent toxic substances in soils, sediments, fishes and human breast milk in southern Vietnam

Ngoc Vinh Nguyen
Global contamination and toxic effects of persistent toxic substances (PTSs) have been an emerging environmental issue and have received considerable attention during the past four decades. The rapid agricultural and industrial growths as well as the expansion of urban areas in Hochiminh City and Mekong River Delta, two of the most densely populated areas in the world with about 26 million peoples, result in the widespread contamination of PTSs in southern Vietnam. Due to adverse...

Development of the Jungfraujoch multiwavelength lidar system for continuous observations of the aerosol optical properties in the free troposphere

Gilles Larchevêque
Climate changes and global warming are generally associated with the enhanced greenhouse effect, but aerosols can induce a cooling effect and thus regionally mask this warming effect. Unfortunately, the strong variability both in space and in time of the aerosols and thus the difficulty to characterize their global basic properties induce large uncertainties in the predictions of the numerical models. Those uncertainties are as high as the absolute level of the enhanced greenhouse forcing. To...

Compact test platform for in-situ indentation and scratching inside a scanning electron microscope (SEM)

Rodolfo Rabe
In-situ materials tests have the advantage to link visual and sensor based information during a dynamic experiment. In this thesis, a compact indenter-scratch test device has been built at EPFL-LSRO and installed inside a Scanning Electron Microscope (SEM) at EMPA-Thun. This indenter has been designed having high resolution and long-range stick-slip piezoelectric actuators to position and test the samples. The combination of the SEM high magnification / high depth of focus images and the high...

Regional and local scale pesticide transport in the alluvial plain of the Swiss Rhône River Valley

Kirsten Meiwirth
The herbicide transport and the groundwater vulnerability to pesticide contamination were studied in the alluvial aquifer of the Rhône River Valley near Martigny (Southwest Switzerland). The low clay and organic matter content of the soil, the intensive agricultural use, and the low depth of the groundwater table, lead to an alleged high vulnerability of the groundwater to contamination. Groundwater is used for irrigation, drinking water supply, and industrial purposes; it is of great economic and...

Database Queries in Java

Christopher Ming-Yee Iu
In conventional programming languages like Java, the interface for accessing databases is often inelegant. Typically, an entire separate database query language must be embedded inside a conventional programming language for programmers to access the full power and speed of a database. Programmers, though, prefer working entirely from within their conventional programming languages, both for general-purpose computation and for database access. This thesis explores how database operations can be expressed using the existing syntax of conventional...

Proxys Internet avancés

Philippe Rochat
Since the 90's, the Internet has tremendously evolved in terms of number and diversity of available services. In this trend, proxies are playing a central role and are spread all over the net. Today, the only functionality of proxies is to speed content access through caching only considering statistics based on use made by a user group, all together. Nowadays, evolutions are focusing on two main trends: specific infrastructures that do not comply anymore with...

Probabilistic models for music

Jean-François Paiement
This thesis proposes to analyse symbolic musical data under a statistical viewpoint, using state-of-the-art machine learning techniques. Our main argument is to show that it is possible to design generative models that are able to predict and to generate music given arbitrary contexts in a genre similar to a training corpus, using a minimal amount of data. For instance, a carefully designed generative model could guess what would be a good accompaniment for a given...

Synthesis of Glycomimetics as Potential Anti-Cancer Agents

Annabelle Gillig
Cancer cells exhibit different properties that make them dangerous to the host, such as the ability to invade other tissues and the abnormal response to the control mechanisms that regulate the division of normal cells, which allow them to divide in a relatively uncontrolled fashion. Moreover, cancer cells require fewer protein growth factors than normal cells and can go on dividing indefinitely, in contrast with normal. Thus, malignant tumors cells defy not only the normal...

Non-GMO approach for the improvement of heavy metal accumulation and extraction of high yielding crop species for efficient phytoextraction of contaminated soil

Erika Nehnevajova
Some plants able to take up heavy metals from contaminated soils offer a possibility to clean up sites contaminated with heavy metals. Plants thus act as a solar driven pump, which can extract and concentrate heavy metals from the environment. Since most of the metal hyperaccumulating wild plants only produce very low biomass and most of plants producing high biomass accumulate only moderate amounts of metals, the current research is mainly focused on the overcoming...

Binaural Audio Signal Processing Using Interaural Coherence Matching

Fritz Menzer
Binaural room impulse responses (BRIRs) characterize the transfer of sound from a source in a room to the left and right ear entrances of a listener. Applying BRIRs to sound source signals enables headphone listening with the perception of a three dimensional auditory image. BRIRs are usually linear filters of several hundred milliseconds to several seconds length. The waveforms of the BRIRs contain therefore a vast amount of information. This thesis studies the modeling of...

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