119 research outputs found

    An agent-based model for energy service companies

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    The residential housing sector is a major consumer of energy accounting for approximately one third of carbon emissions in the United Kingdom. Achieving a sustainable, low-carbon infrastructure necessitates a reduced and more efficient use of domestic energy supplies. Energy service companies offer an alternative to traditional providers, which supply a single utility product to satisfy the unconstrained demand of end users, and have been identified as a potentially important actor in sustainable future economies. An agent-based model is developed to examine the potential of energy service companies to contribute to the large scale upgrading of household energy efficiency, which would ultimately lead to a more sustainable and secure energy infrastructure. The migration of households towards energy service companies is described by an attractiveness array, through which potential customers can evaluate the future benefits, in terms of household energy costs, of changing provider. It is shown that self-financing is a limiting factor to the widespread upgrading of residential energy efficiency. Greater reductions in household energy costs could be achieved by committing to longer term contracts, allowing upgrade costs to be distributed over greater time intervals. A steadily increasing cost of future energy usage lends an element of stability to the market, with energy service companies displaying the ability to retain customers on contract expiration. The model highlights how a greater focus on the provision of energy services, as opposed to consumable products, presents a viable approach to reducing future energy costs and usage

    Multi-utility service companies: a complex systems model of increasing resource efficiency

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    Domestic households account for a significant portion of energy consumption and carbon emissions in the United Kingdom. Gains in energy and resource efficiency are undermined by the continuing rise in consumption. A multiutility service company (MUSCo) could enable households to make efficiency improvements through energy technologies and demand management, thus reducing overall consumption. We present a system dynamics model for the domestic energy demand and supply system in the United Kingdom, in which MUSCos compete with traditional utility providers. The market transition toward a leasing contracted service is examined and various potential business models explored

    Acid Polishing of Lead Crystal Glass

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    The industrial partner manufactures high quality lead crystal glassware. The cutting of decorative features in the glass damages the surface and the cuts are optically opaque; to restore transparency, the glass is polished in a solution of hydrofluoric (HF) and sulphuric acid (H2 SO4 .) The polishing process comprises three stages: 1. immersion in a polishing tank containing acid; 2. rinsing in a tank containing water; and 3. settlement of the solid reaction products in a settlement tank. The manufacturer hopes to optimise its polishing process to • minimise the health/environmental impact of the process; • maximise throughput; • maintain the sharpness of the cut edges while still polishing to an acceptable level of transparency. The study group was asked to focus on modelling three aspects of the process: • the chemical reactions involved in the etching at the glass-acid solution interface; • the removal of reaction products in the settlement tank; • flow within the polishing tank

    Sugars content in selected foods in the EU: a 2015 baseline to monitor sugars reduction progress

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    In 2015, as part of the EU Framework for National Initiatives on Selected Nutrients, the EU High Level Group on Nutrition and Physical Activity (HLG) set as a target the reduction of added sugars in food products by a minimum of 10% by 2020 against a 2015 baseline. A suitable monitoring framework is necessary to describe the baseline situation and to evaluate the progress of food reformulation; its development is under way in some EU Member States, as well as part of the Joint Action on Nutrition and Physical Activity (JANPA). This report complements these activities by filling data gaps where needed and by providing a broad geographical coverage based on commercially available data collected in a harmonised way for branded products across Europe. It estimates sugars content from 2015 data for the three product categories identified by the HLG for immediate action: sugars sweetened beverages, breakfast cereals and dairy products. Based on market volume information, this report estimates the amount of total sugars sold to European consumers by these three product categories. By providing the mean sugars content, weighted by market share, for product (sub-) groups, it also highlights the existence of product groups whose reformulation is critical to achieving the 2020 target. The results highlight the need to adopt a multifaceted approach that targets not only individual high-sugars products, but also the products with high market shares that are contributing the highest overall volumes of sugars to consumers, independent of actual total sugars content. These results are calculated using 2015 data from a commercial market research company, Euromonitor International . The analysis is performed for 22 European countries; however, a comparison between countries is not provided due to differing market coverage.JRC.F.1-Health in Societ

    Tropospheric winds from northeastern China carry the etiologic agent of Kawasaki disease from its source to Japan

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    Evidence indicates that the densely cultivated region of northeastern China acts as a source for the wind-borne agent of Kawasaki disease (KD). KD is an acute, coronary artery vasculitis of young children, and still a medical mystery after more than 40 y. We used residence times from simulations with the flexible particle dispersion model to pinpoint the source region for KD. Simulations were generated from locations spanning Japan from days with either high or low KD incidence. The postepidemic interval (1987–2010) and the extreme epidemics (1979, 1982, and 1986) pointed to the same source region. Results suggest a very short incubation period (<24 h) from exposure, thus making an infectious agent unlikely. Sampling campaigns over Japan during the KD season detected major differences in the microbiota of the tropospheric aerosols compared with ground aerosols, with the unexpected finding of the Candida species as the dominant fungus from aloft samples (54% of all fungal strains). These results, consistent with the Candida animal model for KD, provide support for the concept and feasibility of a windborne pathogen. A fungal toxin could be pursued as a possible etiologic agent of KD, consistent with an agricultural source, a short incubation time and synchronized outbreaks. Our study suggests that the causative agent of KD is a preformed toxin or environmental agent rather than an organism requiring replication. We propose a new paradigm whereby an idiosyncratic immune response, influenced by host genetics triggered by an environmental exposure carried on winds, results in the clinical syndrome known as acute KD

    SWIRE: The SIRTF Wide‐Area Infrared Extragalactic Survey

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    The SIRTF Wide-Area Infrared Extragalactic Survey (SWIRE), the largest SIRTF Legacy program, is a wide-area imaging survey to trace the evolution of dusty, star-forming galaxies, evolved stellar populations, and active galactic nuclei (AGNs) as a function of environment, from redshifts to the current z ∼ 3 epoch. SWIRE will survey seven high-latitude fields, totaling 60–65 deg2 in all seven SIRTF bands: Infrared Array Camera (IRAC) 3.6, 4.5, 5.6, and 8 mm and Multiband Imaging Photometer for SIRTF (MIPS) 24, 70, and 160 mm. Extensive modeling suggests that the Legacy Extragalactic Catalog may contain in excess of 2 million IR-selected galaxies, dominated by (1) ∼150,000 luminous infrared galaxies (LIRGs; LFIR 1 1011 L,) detected by MIPS (and significantly more detected by IRAC), ∼7000 of these with ; (2) 1 million IRAC- z 1 2 detected early-type galaxies (∼ with and ∼10,000 with ); and (3) ∼20,000 classical AGNs 5 2 # 10 z 1 1 z 1 2 detected with MIPS, plus significantly more dust-obscured quasi-stellar objects/AGNs among the LIRGs. SWIRE will provide an unprecedented view of the evolution of galaxies, structure, and AGNs. The key scientific goals of SWIRE are (1) to determine the evolution of actively star forming and passively evolving galaxies in order to understand the history of galaxy formation in the context of cosmic structure formation; (2) to determine the evolution of the spatial distribution and clustering of evolved galaxies, starbursts, and AGNs in the key redshift range over which much of cosmic evolution has occurred; and (3) to 0.5 ! z ! 3 determine the evolutionary relationship between “normal galaxies” and AGNs and the contribution of AGN accretion energy versus stellar nucleosynthesis to the cosmic backgrounds. The large area of SWIRE is important to establish statistically significant population samples over enough volume cells that we can resolve the star formation history as a function of epoch and environment, i.e., in the context of structure formation. The large volume is also optimized for finding rare objects. The SWIRE fields are likely to become the next generation of large “cosmic windows” into the extragalactic sky. They have been uniquely selected to minimize Galactic cirrus emission over large scales. The Galaxy Evolution Explorer will observe them as part of its deep 100 deg2 survey, as will Herschel. SWIRE includes ∼9 deg2 of the unique large-area XMM Large Scale Structure hard X-ray imaging survey and is partly covered by the UKIDSS deep J and K survey. An extensive optical/near-IR imaging program is underway from the ground. The SWIRE data are nonproprietary; catalogs and images will be released twice yearly, beginning about 11 months after SIRTF launch. Details of the data products and release schedule are presented
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