Outil | EPFL Graph Search

thumb|Une boîte à outils en bois des années 1950. Un outil est un objet physique utilisé par un être vivant directement, ou par l'intermédiaire d'une machine, afin d'exercer une action le plus souvent mécanique, ou thermique, sur un élément d'environnement à traiter (matière brute, objet fini ou semi-fini, être vivant, etc). Il améliore l'efficacité des actions entreprises ou donne accès à des actions impossibles autrement. Beaucoup procurent un avantage mécanique en fonctionnant selon le principe d'une machine simple, comme la pince-monseigneur, qui exploite le principe du levier. Description thumb|Un marteau de charpentier, auquel la panne en ajoute la fonction . L'outil peut être compris comme un prolongement de la main, du corps, un intermédiaire d'action, voire comme une prothèse, dans le sens où il remplace (ou même crée) un membre ou un organe ( signifie d'ailleurs en grec « instrument, outil »). Pour Michel Serres, l'homme est un animal despécialisé et l'outil qu

STOCHASTIC PROCESSES AND CONSTRUCTION OF BROWNIAN MOTION

Christophe-Aschkan Mery

This project offers a rigorous introduction to the tools needed to construct a continuous stochastic process. Among other things, we give a very detailed proof of the Kolmogorov continuity criterion. We then construct a Brownian Motion following the formalism of D. Revuz and M. Yor. That is, we see the BM as a linear isometry from a Hilbert space into a Gaussian space.

EPFL2013

Seeking methods for improving sustainability in the extractive sector

Farnaz Eslamishoar

Extractive resources are indisputably a necessary component of international sustainable development. Despite current advancements in the circular economy, world production needs for raw materials are ever increasing, and still a long way remains for it to become rather independent from mineral resources. At the same time, mining has too many negative stories in news headlines about its trade-offs for the environment and human health, which hinders sustainable growth. This thesis deals with this integral dilemma in three chapters. In Chapter 1, I have made an extensive effort to understand the socio-political aspects of the mining business, both internationally and specifically in the context of a developing country, and on the issue of the corporate social responsibility the company requires. I then continued with gathering my primary sources of data for answering my first question: What are the primary social variables contributing to mining sustainability issues? I derived theories from Economic Growth in the Political Economy and Institutional Void from Management Science, trying to place my findings in a broader context. I concluded this chapter with underlying sociopolitical factors interfering with sustainable mining practices. This has led to the shaping of the second chapter of my thesis. Chapter 2 builds on the given that throughout the model of Economic Growth, technological change can happen within a shorter timeline and that new technologies lead to more efficiency in the Process Innovation. The mining industry is no exception. Yet, my quick review at the time revealed that this industry is lagging incumbent mainstream businesses in technological adoption. I therefore made my aim here to discuss conditions for transitions towards a more technologically innovative mining business. I surveyed mining firms internationally and noted the critical criteria for responsible practices. I then made what had been to my knowledge and ability, an exhaustive grouping of innovative technologies for the different sectors of mining firms. These tools granted me the ability to perform different multivariate analyses and decide on the best method for benchmarking different technology groups based on these criteria. In the later part of my thesis (Chapter 3), having these findings in hand and all experiences and observations in place with my assumptions, I decided to take one step back to ask whether the criteria I have for measuring mining sustainability are the correct measures by looking through the question using emerging data science tools. Are the sustainability scopes commonly discussed in the mining community the most crucial sustainability problems of this sector? Having the sustainability reports of all major international mining firms in hand, I evaluated around 3500 documents containing 8 million words discussing current sustainability matters pertaining to mining firms. Through implementing appropriate algorithms of Topic Modeling, I introduced five new main scopes for mining sustainability used to examine the discourse and groupings through this framework to observe any possible differences among the conventional and the generated lists. The results of my thesis are my two conceptual frameworks, technological benchmarking assessment tools, and a data-driven sustainability domains list, as well as the innovation policy recommendations for the mining community.

EPFL2021

Exploiting co-adaptation for the design of symbiotic neuroprosthetic assistants

Babak Mahmoudi

The success of brain-machine interfaces (BMI) is enabled by the remarkable ability of the brain to incorporate the artificial neuroprosthetic 'tool' into its own cognitive space and use it as an extension of the user's body. Unlike other tools, neuroprosthetics create a shared space that seamlessly spans the user's internal goal representation of the world and the external physical environment enabling a much deeper human-tool symbiosis. A key factor in the transformation of 'simple tools' into 'intelligent tools' is the concept of co-adaptation where the tool becomes functionally involved in the extraction and definition of the user's goals. Recent advancements in the neuroscience and engineering of neuroprosthetics are providing a blueprint for how new co-adaptive designs based on reinforcement learning change the nature of a user's ability to accomplish tasks that were not possible using conventional methodologies. By designing adaptive controls and artificial intelligence into the neural interface, tools can become active assistants in goal-directed behavior and further enhance human performance in particular for the disabled population. This paper presents recent advances in computational and neural systems supporting the development of symbiotic neuroprosthetic assistants.

2009

Seeking methods for improving sustainability in the extractive sector

Farnaz Eslamishoar

EPFL2021