809 research outputs found

    Adapting the economic level of leakage concept to include carbon emissions, and application with limited data

    Get PDF
    The Economic Level of Leakage is a systematic way for a water utility to estimate the optimum leakage level below which the costs of reducing leakage further exceed the benefits of saving water. The concept can be adapted to include the economic costs of social and environmental externalities. The paper presents an approach for estimating the economic costs of greenhouse gas emissions and Incorporating these in the ELL calculation. This is applied in the city of Zaragoza in Spain, with initial estimates of ELL and externality costs calculated using data from water supply records and measurements in a study area, together with empirical relationships from the literature

    Clothedral

    Get PDF

    Economic level of leakage (ELL) calculation with limited data: an application in Zaragoza.

    Get PDF
    The Economic Level of Leakage is a systematic way for a water utility to estimate the optimum leakage level below which the costs of reducing leakage further exceed the benefits of saving water. This is applied in the city of Zaragoza in Spain, with initial estimates of ELL calculated using the Bursts and Background Estimates (BABE) approach with data from water supply records and measurements in a study area, together with empirical relationships from the literature. The analysis shows considerable scope for water loss recovery using active leakage control. The same approach could be used in other cities with limited data, to assess the potential benefits from water loss management

    Thermal Transport Across Graphene Step Junctions

    Get PDF
    Step junctions are often present in layered materials, i.e. where single-layer regions meet multi-layer regions, yet their effect on thermal transport is not understood to date. Here, we measure heat flow across graphene junctions (GJs) from monolayer to bilayer graphene, as well as bilayer to four-layer graphene for the first time, in both heat flow directions. The thermal conductance of the monolayer-bilayer GJ device ranges from ~0.5 to 9.1x10^8 Wm-2K-1 between 50 K to 300 K. Atomistic simulations of such GJ device reveal that graphene layers are relatively decoupled, and the low thermal conductance of the device is determined by the resistance between the two dis-tinct graphene layers. In these conditions the junction plays a negligible effect. To prove that the decoupling between layers controls thermal transport in the junction, the heat flow in both directions was measured, showing no evidence of thermal asymmetry or rectification (within experimental error bars). For large-area graphene applications, this signifies that small bilayer (or multilayer) islands have little or no contribution to overall thermal transport

    Identifying Birds' Collision Risk with Wind Turbines Using a Multidimensional Utilization Distribution Method

    Get PDF
    Renewable energy plays a key role in reducing greenhouse gas emissions. However, the expansion of wind farms has raised concerns about risks for bird collisions. We tested different methods used to understand whether birds' flight occurs over wind turbines and found kernel density estimators outperform other methods. Previous studies using kernel utilization distribution (KUD) have considered only the 2 horizontal dimensions (2D). However, if altitude is ignored, an unrealistic depiction of the situation may result because birds move in 3 dimensions (3D). We quantified the 3D space use of the Griffon vulture (Gyps fulvus) in El Estrecho natural park in Tarifa (southern Spain, on the northern shore of the Strait of Gibraltar) during 2012-2013, and, for the first time, their risk of collision with wind turbines in an area in the south of Spain. The 2D KUD showed a substantial overlap of the birds' flight paths with the wind turbines in the study area, whereas the 3D kernel estimate did not show such overlap. Our aim was to develop a new approach using 3D kernel estimation to understand the space use of soaring birds; these are killed by collision with wind turbines more often than any other bird types in southern Spain. We determined the probability of bird collision with an obstacle within its range. Other potential application areas include airfields, plane flight paths, and tall buildings. (c) 2020 The Authors. Wildlife Society Bulletin published by Wiley Periodicals, Inc. on behalf of The Wildlife Society.Peer reviewe

    Software and Analysis for Dynamic Voronoi Diagrams in the Hilbert Metric

    Full text link
    The Hilbert metric is a projective metric defined on a convex body which generalizes the Cayley-Klein model of hyperbolic geometry to any convex set. In this paper we analyze Hilbert Voronoi diagrams in the Dynamic setting. In addition we introduce dynamic visualization software for Voronoi diagrams in the Hilbert metric on user specified convex polygons

    Blockchain and the World of Data

    Get PDF
    This is a video recording of a Workshop presented during the AIS 2022 Student Chapter Leadership Conference (SCLC) Blockchain and the World of Dat

    Involvement of right dorsolateral prefrontal cortex in ill-structured design cognition: An fMRI study

    Get PDF
    In ill-structured tasks, the problem to be solved is poorly specified and there is no unique correct solution. Most evidence on brain mechanisms involved in dealing with such tasks comes from neuropsychology. Here, we developed an ill-structured design task suitable for testing in a functional neuroimaging environment and compared it with a matched well-structured problem-solving task using fMRI. Consistent with prior neuropsychological results, the design task was associated with greater activity in right dorsolateral prefrontal cortex compared with problem solving. This differential activity was specific to the problem studying phase rather than performance. Furthermore, the design and problem-solving tasks differed not only in overall levels of brain activity but also in patterns of functional interactions between brain regions. These results provide new evidence on the role of right dorsolateral prefrontal cortex in ill-structured situations, such as those involved in design cognition. Additionally, these results confirm the suitability of functional neuroimaging for studying such situations

    Remission of intestinal Behçet's disease treated with anti-tumor necrosis factor α monoclonal antibody (Infliximab)

    Get PDF
    Behçet's disease (BD) is a chronic relapsing multisystem disease characterized by oral ulceration, genital ulceration and ocular lesions. Gastrointestinal involvement is rare, often difficult to treat and associated with a high mortality rate. We treated a 47-year-old Korean man with BD who had a recurrent intestinal ulcer with tumor necrosis factor α antibody (infliximab); he initially underwent right hemicolectomy due to uncontrolled intestinal bleeding. For patients with intestinal BD who fail to respond to conventional treatment, infliximab may be a safe and effective new therapeutic option

    The Astropy Problem

    Get PDF
    The Astropy Project (http://astropy.org) is, in its own words, "a community effort to develop a single core package for Astronomy in Python and foster interoperability between Python astronomy packages." For five years this project has been managed, written, and operated as a grassroots, self-organized, almost entirely volunteer effort while the software is used by the majority of the astronomical community. Despite this, the project has always been and remains to this day effectively unfunded. Further, contributors receive little or no formal recognition for creating and supporting what is now critical software. This paper explores the problem in detail, outlines possible solutions to correct this, and presents a few suggestions on how to address the sustainability of general purpose astronomical software
    corecore