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showing 10 items of 32085 documents
Energy Policies and Sustainable Management of Energy Sources
2017
Sustainability of current energy policies and known mid-term policies are analised in their multiple facets. First an overview is given about the trend of global energy demand and energy production, analysing the share of energy sources and the geographic distribution of demand, on the basis of statistics and projections published by major agencies. The issue of sustainability of the energy cycle is finally addressed, with specific reference to systems with high share of renewable energy and storage capability, highlighting some promising energy sources and storage approaches.
Impact Analysis Using Life Cycle Assessment of Asphalt Production from Primary Data
2020
Road construction and maintenance have a great impact on the environment, owing to the huge volumes of resources involved. Consequently, current production procedures and technologies must be properly investigated, for identifying and quantifying the life cycle environmental impacts produced. In this paper, primary data, i.e., site-specific data directly collected or measured on a reference plant, are analyzed for calculating the impact of the production of a hot mix asphalt. The analysis is performed in a from &ldquo
Training Secondary Education Teachers through the Prism of Sustainability: The Case of the Universitat de València
2018
Designing the training of future teachers through holistic and interdisciplinary visions is vital to developing coherent contents, epistemologies, and methodologies that put Education for Sustainability into action. The research presented here analyzes the teaching guides from the curriculum for the Master&rsquo
Combined gasification-oxidation system for waste treatment with supercritical water: Lca and performance analysis
2020
In this study the environmental performance of a first-of-its-kind integrated process based on supercritical water gasification and oxidation (SCW-GcO), was evaluated using life cycle assessment (LCA). The process was applied to the treatment of carbon black and used oil as model wastes. Mass and energy balances were performed using Aspen Plus, and the environmental assessment was carried out through SimaPro. A “from cradle to grave” approach was chosen for the analysis, considering impact categories such as climate change, ozone depletion, human toxicity, particulate matter, land use, resource depletion, and other relevant indicators. The environmental profile of the SCW-GcO process was co…
Renewable energy growth and the financial performance of electric utilities: A panel data study
2017
Electric utilities are under pressure to increase clean energy production. Although the adoption of renewable energy can improve the utilities' environmental performance, a fundamental question is if it also pays in economic terms. Building on the natural-resource-based view of the firm, we answer this question using two data analysis methods. First, we carry out a regression analysis of panel data from 66 large electric utilities covering the period 2005–2014, applying both a fixed and random effects estimator. Subsequently, we use the Granger causality test to explore possible causality links. Our results show a negative correlation at the firm level between renewable energy increase and …
Evaluating the material resource efficiency of secondary aluminium production: A Monte Carlo-based decision-support tool
2019
The contamination of aluminium streams during the different life cycle stages by alloy mixing and/or accumulation of foreign elements, in combination with the limited melt purification options during remelting, represents an important limiting factor in recycling. Consequently, in secondary aluminium production, primary aluminium is used to dilute the concentration of the residual elements, and alloying elements are added to adjust the composition to the target alloy specifications. However, adding elements, for which their refinement in a subsequent recycling step is problematic, results in permanent down-cycling or ‘quality losses’. Hence, it is crucial to more efficiently control the com…
Energy and economic analysis of air-to-air heat pumps as an alternative to domestic gas boiler heating systems in the South of Italy
2019
Abstract According to the electricity tariff recently issued by the Italian government for the domestic heating systems fed with heat pumps (HP), an energy and economic analysis was carried out with the aim of investigating the effectiveness of the air-to-air heat pump systems (HPS) as an alternative to the traditional heating using domestic gas boilers systems (GBS). For the purpose of this study, the apartments of three residential buildings were examined. The hourly heating loads were calculated with the ASHRAE radiant time series and the coefficient of performance (COP) of the HPs was evaluated for each operating condition. The costs for the heating system installation and electricity a…
Fast pyrolysis of hot-water-extracted and delignified silver birch (Betula pendula) sawdust by Py-GC/MS
2017
The thermochemical behavior of birch (Betula pendula) sawdust both untreated and after various chemical treatments (hot-water extraction, delignification, and hot-water extraction followed by delignification) was investigated by pyrolysis-gas chromatography-mass spectrometry (Py-GC/MS). In each case, major GC-amenable condensable products were classified into several compound groups, and the formation of these monomer-related fragments from feedstock samples with varying mass portions of the structural constituents (cellulose, hemicelluloses, and lignin) were determined at 500 °C and 700 °C at hold times of 5 s and 20 s. The formation of pyrolysis products was shown to be characteristically…
A 3D Non-Stationary Cluster Channel Model for Human Activity Recognition
2019
Author's accepted manuscript. © 2019 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works. This paper proposes a three-dimensional (3D) non- stationary fixed-to-fixed indoor channel simulator model for human activity recognition. The channel model enables the formulation of temporal variations of the received signal caused by a moving human. The moving human is modelled by …
Comments on “Overflow characteristics of streamlined weirs based on model experimentation” by Bagheri S. and Kabiri-Samani A
2021
Abstract In this paper the stage-discharge equation of a streamlined weir is theoretically deduced applying the Π-Theorem of dimensional analysis and the self-similarity theory. The coefficients of the new stage-discharge relationship are estimated using the experimental results by Bagheri and Kabiri-Samani.