142 research outputs found

    Use of recycled concrete fines in cement and as aggregate

    Get PDF
    The research project focused on investigating and optimizing the processing and use of recycled crushed sand 0/4 from concrete demolition waste, as an alternative raw material in the cement and concrete industry. Crushed sand is produced during the processing of concrete demolition waste. The goal was to identify the optimum way of using the processed material along the entire process chain so that greenhouse gas emissions, waste volumes are reduced, and natural resources are conserved. Different samples of laboratory and real crushed concrete fines were collected and examined in relation to various possible applications in accordance with the applicable standards. Results highlight, that crushed concrete fines can be used in various applications in the concrete value-chain. However, for an optimal usage, additional processing is needed

    Linking Models of Land Use, Resources, and Economy to Simulate the Development of Mountain Regions (ALPSCAPE)

    Get PDF
    We present a framework of a scenario-based model that simulates the development of the municipality of Davos (Swiss Alps). We illustrate our method with the calculation of the scenario for 2050 "Decrease in subsidies for mountain agriculture and liberalization of markets.” The main objective was to link submodels of land-use allocation (regression-based approach), material and energy flows submodels (Material and Energy Flux Analysis), and economic submodels (Input-Output Analysis). Letting qualitative and quantitative information flow from one submodel to the next, following the storyline describing a scenario, has proven to be suitable for linking submodels. The succession of the submodels is then strongly dependent on the scenario. Qualitative information flows are simulated with microsimulations of actor choices. Links between the submodels show different degrees of robustness: although the links involving microsimulations are the weakest, the uncertainty introduced by the land-use allocation model is actually advantageous because it allows one possible change in the landscape in the future to be simulated. The modeling results for the scenario here presented show that the disappearance of agriculture only marginally affects the region's factor income, but that the consequences for the self-sufficiency rate, for various landscape-related indicators and ecosystem services, and for the economy in the long term may be considerable. These benefits compensate for agriculture's modest direct economic value. The framework presented can potentially be applied to any region and scenario. This framework provides a basis for a learning package that allows potential detrimental consequences of regional development to be anticipated at an early stag

    Material flow and economic analysis as a suitable tool for system analysis under the constraints of poor data availability and quality in emerging economies

    Get PDF
    Waste from electrical and electronic equipment or e-waste is increasingly processed in transitional or developing countries. The waste originates from both national consumption and waste imports. In these countries the e-waste processing and recycling is managed almost entirely by informal recycling businesses. Due to the application of inappropriate techniques, this sector bares high risks of environmental and occupational hazards and also looses valuable materials. Formal recycling industries have to compete with the informal businesses and simultaneously comply with environmental and occupational regulations. The presented model applies a dynamic stock-driven material flow model and an economic evaluation of gold and copper flows to the Indian personal computer (PC) recycling sector. The metal concentration per PC and value of these metals mainly determine the profits for recyclers. The study introduced threshold values for formal and informal gold and copper recycling according to their recycling cost per PC. At present level of metal concentration per PC and metal prices the formal sector will not become active. Two scenarios, one with double metal prices and a second with reduced threshold values for formal recycling, have been calculated. Also under theses scenarios the formal recycling sector will not overtake a majority of the recycling. The model proves that a stock-driven dynamic material flow model can be combined with an economic evaluation of material flows. The analysis included a calculation of error propagation and a sensitivity analysi

    Critical review of strategic planning research in hospitality and tourism

    Get PDF
    Strategic planning remains one of the most popular management tools, but theoretical and empirical developments in the academic literature have been a slow burn. This paper addresses this gap and provides an up-to-date review of hospitality and tourism strategic planning research. We review strategic planning research from 1995 to 2013 in seven leading tourism academic journals, and adopt a modern and broad conceptualization of strategic planning. While there is some awareness of effective tourism strategic planning processes, academic research has not kept pace with practice. To stimulate a resurgence of research interest, we provide future research directions. We observe a methodological introspection and present some new research methodologies, which are critically important in researching the turbulent, chaotic and nonlinear tourism environment

    Tourism economics research: A review and assessment

    Get PDF
    This paper aims to provide the most up-to-date survey of tourism economics research and to summarise the key trends in its recent development. Particular attention is paid to the research progress made over the last decade in respect of approaches, methodological innovations, emerging topics, research gaps, and directions for future research. Remarkable but unbalanced developments have been observed across different sub-research areas in tourism economics. While neoclassical economics has contributed the most to the development of tourism economics, alternative schools of thought in economics have also emerged in advancing our understanding of tourism from different perspectives. As tourism studies are multi- and inter-disciplinary, integrating economics with other social science disciplines will further contribute to knowledge creation in tourism studies

    Nachhaltig bauen - Lebenszyklus, Systeme, Szenarien, Verantwortung

    No full text
    Dem Bauwesen kommt bei der Zielsetzung einer Nachhaltigen Entwicklung eine grosse Bedeutung zu. "Nachhaltig Bauen" bedeutet vereinfacht ausgedr\ufcckt, Bauwerke zu errichten und zu erhalten, die ein Kapital f\ufcr zuk\ufcnftige Generationen darstellen und keine Altlast.Das Buch bietet einen Einstieg in diese Thematik \ufcber drei Zug\ue4nge: Denkschule, Handwerkszeug und Beispiele. Es wird der bestehenden Baupraxis ein Ansatz gegen\ufcbergestellt, der sich am gesamten Lebenszyklus der Bauwerke orientiert und ein Denken und Planen in Systemen und Szenarien voraussetzt. Dies erfordert ein modernes Selbstverst\ue4ndnis des Planenden, der bei s\ue4mtlichen Prozessen der Planung und Bewirtschaftung die Verantwortung \ufcbernimmt und sich nicht nur auf den Entwurf beschr\ue4nkt. Beispiele Nachhaltigen Bauens veranschaulichen m\uf6gliche L\uf6sungsans\ue4tze und zeigen auf, welche Ideen funktionieren oder wo noch optimiert werden kann. Ein Anhang mit einer umfassenden cbersicht zu Instrumenten f\ufcr Nachhaltiges Bauen erg\ue4nzt die Publikation.- Umfasst den ganzen Lebenszyklus von Bauten, von der Herstellung \ufcber die Nutzung bis zur Entsorgung.- Thematisiert viele Teilbereiche: u.a. Projektmanagement, Life Cycle Management, Facility Management, Immobilieninvestition.- Enth\ue4lt einen umfassenden Anhang zu Instrumenten und Hilfsmitteln

    Benchmarking electricity consumption

    No full text
    The building stock is one of the largest energy consumers and simultaneously represents a relevant cost driver for most companies. Thus, buildings should be optimally planned, constructed and used from both an environmental and from an economic perspective. Benchmarking electricity consumption in the usage phase is a tool for achieving this objective. This requires a uniform collection of key usage indicators on the one hand, and on the other hand it is necessary to be cognisant of the factors that drive these key indicators and how they do so. This alone makes it possible to satisfy the benchmarking principle of comparing like or similar objects. Uniformly collected key indicators for electricity consumption (kWh/m2 usable floor area and year) are presented on the basis of 109 Swiss office buildings. This is broken down into further groupings on the basis of the relevant drivers. The analysis of the drivers relies on regression analysis. This demonstrates above all the great relevance of technical installation (e.g. the share of mechanically vented and ventilated as well as air-conditioned areas), given that the coverage area of such systems has a significant effect on the electricity consumption of office buildings. Accordingly, special attention should be paid to the planning, construction and use of technical installations, in order to be able to provide optimally energy-efficient buildings.Benchmarking, energy, electricity consumption, office,
    corecore