52 research outputs found

    Bioenergy in Switzerland: Assessing the domestic sustainable biomass potential

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    This paper analyzes the sustainable domestic biomass potential for bioenergy in Switzerland. Relevant biomass resources were selected based on expert interviews and literature analyses. A definition of technical and sustainable biomass potentials was developed. The technical and sustainable biomass potentials were then assessed based on technical and sustainability constraints. The sustainable potentials were further subdivided into the already energetically-used potential and the remaining biomass potential. Data was collected from the literature and supplementary interviews with field experts. Finally, the primary energy potential from biomass was calculated and compared to the current Swiss energy demand

    A novel experimental approach for studying spontaneous imbibition processes with alkaline solutions

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    Spontaneous imbibition processes can play an important role in oil production. It can be enhanced or influenced by wettability changes generated by properly designed chemicals or by the natural surfactants resulting from reactive crude oils in the presence of alkaline solutions. The reaction of basic salts with some components of oil can, indeed, lead to the formation of natural soaps that reduces the interfacial tension between oil and brine. The latter scenario is studied herein on samples and oil from the St Ulrich oil field in the Vienna basin. To that end, spontaneous imbibition experiments were performed with two brines differing by the absence or presence of alkali. We first present a general novel technique to monitor saturation changes on small rock samples for the purpose of assessing the efficiency of a given recovery process. Samples of only 15 mm in diameter and 20 mm in length and set at irreducible saturation were fully immersed in the solution of interest, and the evolution of the samples’ saturation with time was monitored thanks to a dedicated NMR technique involving the quantification of the sole oil phase present within the sample. A fully-3D imbibition configuration was adopted, involving counter-current flows through all faces of the sample. The experimental method is fast for two reasons: (i) the kinetics of capillary imbibition process is proportional to the square of sample size, i.e. very rapid if accurate measurements can be acquired on tiny samples, (ii) the present 3D situation also involves faster kinetics than the 1D configuration often used. The NMR technique was crucial to achieve such conditions that cannot be satisfied with conventional volumetric methods. The kinetics of oil desaturation during spontaneous imbibition is interpreted with the help of an analytical 3D diffusion model. For the alkaline solution, the diffusion coefficient is reduced by a factor of only two compared to the non-alkaline brine, although the interfacial tension between the oil and the imbibing solution is reduced by a factor of 10. Hence, a wettability change to a more water wet state has to be assumed when the alkaline solution replaces the non-alkaline solution in the imbibition process. However, no significant impact on the final saturation was observed

    The Black Square Problem. Analyse et développement d’un logiciel dédié

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    Le Black Square Problem est un exercice réalisé dans le domaine du design. Ce dernier demande un haut niveau de cognition, ce qui peut impliquer des problématiques lorsqu'il est réalisé informatiquement. Cette étude s'intéresse à ces problématiques et en tient compte par la création d'un logiciel dédié. Six étudiants de la Webster University suivant un cours de design ont participé à cette étude, deux dans le cadre d'une analyse concurrentielle et quatre lors d’un test utilisateur du logiciel dédié. Le logiciel est développé sur le framework Electron avec pour principaux langages de programmation le JavaScript et HTML/CSS. Ce dernier a été développé en se basant sur l'analyse des besoins et les préconisations de la littérature quant à l'ergonomie, les modèles d'acceptation utilisateur et de dynamique d'affect. Les tests utilisateurs sur le logiciel dédié ont montré une évaluation générale plus élevée que la moyenne dans les dimensions mesurées de facilité d'utilisation, facilité d'apprentissage, utilité et satisfaction. Un logiciel, dédié et réduit des fonctionnalités superflues, est donc plus adapté à une utilisation spécifique à un cadre précis

    Avaliação de práticas educativas de compostagem: multi interesses e visões

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    O presente estudo busca descrever e analisar vivênvias em oficinas de compostagem e avaliar sob a ótica dos interesses e proposições dos participantes envolvidos. A etapa metodológica propõe pesquisa bibliográfica e documental, além de pesquisas de campo através de oficinas, registradas por relatórios, fotografias e entrevistas semi-estruturadas. O momento teórico foi subdividido pelos temas visão de mundo, construção do conhecimento, o problema, impacto e resposta técnica como estratégia pedagógica no planejamento de atividades educativas ambientais. Além de referências teóricas, o momento empírico avalia as observações de campo e entrevistas, cada uma em três categorias, respectivamente: características do grupo/projeto, processo da oficina e sua artesania e os resultados esperados e obtidos; interesse-motivo, resultado-aprendizado e crítica-avaliação-proposição. Como síntese, o momento analítico apresenta relações produzidas nas etapas do estudo. Os resultados evidenciam potencial em referenciais teóricos e éticos como ferramentas básicas para planejamento prévio de oficinas e às questões elaboradas. A visão sistêmica contribui para construção de diálogos e trocas. Ferramentas de gestão compartilhada reforçam o processo de participação coletivaThe present study seeks to describe and analyse experiences in composting workshops and to evaluate from the point of view of the interests and propositions of the participants involved. The methodological stage suggests bibliographic and documental research, such as field research through workshops registered by reports, fotographs and semi-structured interviews. The theoretical moment was divided by the themes world vision, knowledge building, the problem, impact and technical response as a pedagogical strategy on planning environmental educational activities. Beyond theorical references, the empirical moment evaluates field observations and interviews, each one in three categories, respectively: group/project characteristics, workshop process and its crafts and the expected and obtained results; motive-interest, learning-result and critical-evaluation-proposal. As synthesis, the analytical moment presents relations produced in the stages of the study. The results show potential in theoretical and ethical references as basic tools to pre-planning of workshops and to the elaborated questions. The systemic vision contributes to the construction of dialogues and exchanges. Shared management toold reinforce the coletive participation proces

    Trade in Health Services - An Analytical Framework Valuation Effects and Interest Rate Changes

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    The present paper deals with a topic that pertains to Health Economics as well as to Trade Theory – Trade in Health Services. It is intended to deliver an analytical framework for the assessments of this new sector of international trade which takes into account both the ‘general welfare aspects’ and the effects for the achievement of general ‘health system goals’. While to former will be scrutinized by the subcategories allocation, accumulation and location effects, the latter is aligned with the OECD Health System Performance Framework which mentions three major health system goals that are ‘Health Improvement & Outcome’, ‘Responsiveness & Access’ and ‘Financial Contribution & Health Expenditures’. For this purpose trade in Health Services is split up according to the four modes of service supply introduced by the General Agreement of Trade in Services (GATS). For each mode examples are enclosed and the current level of trade is analysed. It is also examined what are the major obstacles for trade in these modes and what liberalization perspectives are given. The subsequent discussion and plausibility considerations of how each mode may contribute to improve efficiency as well as equity in national health systems is a systematic starting point for further research. It provides a first insight in how trade in Health Services could help to overcome resource constraints in national health systems as well as allude to the potential risks of which sight shouldn’t be lost.
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