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Founded in 1994, Alternatives, Action and Communication Network for International Development, is a non-governmental, international solidarity organization based in Montreal, Quebec, Canada. Alternatives works to promote justice and equality amongst individuals and communities worldwide. Active in over 35 countries, Alternatives supports local, community-based initiatives working towards the greater economic, social, and political rights of people and communities affected by poverty, discrimination, exploitation, and violence. The organization publishes the Le Journal des Alternatives newsletter, a publication inserted every three months in Montreal's French paper Le Voir. Alternatives also publishes the Alternatives International Journal, a monthly publication in English distributed electronically. Alternatives Montreal is the headquarters of an International Federation consisting of nine NGOs spread across the world. Alternative-Niger, Alternatives Asia (New Delhi), Alternative

From pulsed-DCMS and HiPIMS to microwave plasma-assisted sputtering: Their influence on the properties of diamond-like carbon films

David Brown, Caroline Hain, Aïcha Hessler-Wyser, Johann Michler, Thomas Nelis

The fabrication of high-hardness non-hydrogenated diamond-like carbon (DLC) via standard magnetron sputtering (MS) is often hindered by the low sputtering yields and ionisation rates of carbon, therefore investigations into pulsed alternatives of MS, else sputtered species post-ionisation methods, are of particular interest. This work focuses on investigating the influence of pulsed-direct current MS (pDCMS), high power impulse magnetron sputtering (HiPIMS) and their microwave plasma-assisted (MA-pDCMS, MA-HiPIMS) variants on the properties of the fabricated DLC films. Two setups were used for the pDCMS-and HiPIMS-based methods, respectively. The films were characterised using Raman spectroscopy, nanoindentation, X-ray reflectometry and scanning electron microscopy, where the pDCMS-produced films were additionally characterised by film-stress measurements. Moreover, in situ time-resolved Langmuir probe plasma analysis was performed under HiPIMS and MA-HiPIMS conditions to analyse the influence of the magnetron and microwave plasmas on one another. For both DCMSand HiPIMS-based procedures, it was found that the addition of microwave plasma did not facilitate attaining hardnesses beyond 30 GPa, however, it did enable modifying the morphology of the films. Furthermore, this study shows the potential of synchronised sputtering with substrate biasing, as well as the importance of microwave plasma source positioning in relation to the substrate.

ELSEVIER SCIENCE SA2022

The Hydro-Morphological Index of Diversity

Walter Gostner

Contemporary river engineering must guarantee effective long-term flood protection while also improving stream ecology. Nowadays, river engineering projects must aim at optimizing hydromorphological heterogeneity, as this is an acknowledged basic condition for maintaining stream biodiversity. In the present project, a new Hydro-Morphological Index of Diversity (HMID) was developed. The purpose of the HMID is to deliver a tool for the practitioner engaged in planning of integrated river engineering projects where habitat enhancement constitutes one of the project targets. By calculating the HMID, a quantitative statement of habitat heterogeneity enhancement for different project alternatives is possible, and therefore recommendations of which alternatives to prioritize from an ecomorphological perspective can be given. The HMID was developed within the framework of the "Integrated River Management" project, an interdisciplinary research program involving different University Institutes in Switzerland. During extensive field campaigns, hydraulic and geomorphic data were recorded at morphologically contrasting sites at three streams in Switzerland (Bünz, AG; Venoge, VD; Sense, FR/BE). By means of correlation analysis, relationships between the measured variables could be detected. Being significantly correlated to a number of hydraulic and geomorphic variables, the hydraulic variables flow velocity and water depth were found to accurately represent the hydromorphological template of a stream. A formula for the HMID could be proposed by comparing the variability of these two hydraulic variables between the study reaches. The developed formula used the coefficient of variation of flow velocity and water depth as a measure to describe hydromorphological variability. A good correlation of HMID scores with rankings obtained by means of a multimetric visual habitat assessment method supported the capability of the HMID to represent the hydromorphological state of a stream. Correlation between HMID scores and macroinvertebrate-based biotic indices, on the other hand, did not meet expectations for all tested stream reaches. Numerical modelling for the study reaches at the river Sense was conducted to examine the temporal variability of the hydraulic variables and the HMID. HMID scores were calculated for different discharges in river, and temporal variability was lower in natural than in channelized reaches. The increments of hydraulic variables for changing discharge are greater in channelized than in natural reaches. Thus, aquatic biota in channelized reaches must cope not only with a degraded habitat template but also with higher stress conditions. However, physical habitats in natural reaches lose stability when discharges with major bed reshaping processes occur. These high discharges correspond to intermediate disturbance events, which are important towards maintaining ecological functions. In a case study, the suitability of the HMID for application was demonstrated. After completion of a restoration project, a stream reach should be characterized by a high HMID and a stable temporal variability (unless discharges above a disturbance threshold occur). In this way, the HMID provides the necessary hydromorphological template to achieve a high ecological potential for a restored stream reach. However, it must be avoided that high hydromorphological heterogeneity does not become a primary aim in itself. For a sound restoration project, processes at the watershed scale also must be included. In particular, it is necessary to evaluate the sediment regime of the entire watershed (mainly of the upstream areas), to estimate the long-term geomorphic evolvement of the project reach and to verify whether a dynamic equilibrium for the reach can be obtained. Finally, the ecological success of habitat enhancement measures depends on the conditions of other potential stressors (e.g. sediment or excessive nutrients, chemical pollution, habitat fragmentation, strongly modified flow regime). An integrated vision of these factors is a primordial rule for ecologically successful river restoration projects.

EPFL2012

Price-based regulation of oligopolistic markets under discrete choice models of demand

Michel Bierlaire, Stefano Bortolomiol, Virginie Janine Camille Lurkin

We propose a framework to find optimal price-based policies to regulate markets characterized by oligopolistic competition and in which consumers make a discrete choice among a finite set of alternatives. With this framework, we can include general discrete choice models available in the literature to capture heterogeneous consumer behavior. In our work, consumers are utility maximizers and are modeled according to random utility theory. Suppliers are modeled as profit maximizers, according to the traditional microeconomic treatment. Market competition is modeled as a non-cooperative game, for which an ε-equilibrium solution is sought. Finally, the regulator can affect the behavior of all other agents by giving subsidies or imposing taxes to consumers. In transport markets, economic instruments might target specific alternatives, to reduce externalities such as congestion or emissions, or specific segments of the population, to achieve social welfare objectives. In public policy, different agents have different individual or social objectives, possibly conflicting, so value judgements are used to compare monetary and non-monetary objectives. We present a mixed integer optimization model to find optimal policies subject to supplier profit maximization and consumer utility maximization constraints. Then, we propose a model-based heuristic approach based on the fixed-point iteration algorithm that finds ε-equilibrium solutions for the market. Numerical experiments on an intercity travel case study show how the regulator can optimize its decisions for different policy instruments and for different objective functions.

EPFL2021

The Hydro-Morphological Index of Diversity

Walter Gostner

EPFL2012