The production of W bosons in association with two jets in proton-proton collisions at a centre-of-mass energy of ...s = 7 TeV has been analysed for the presence of double-parton interactions using ...data corresponding to an integrated luminosity of 36 pb super(-1), collected with the ATLAS detector at the Large Hadron Collider. The fraction of events arising from double-parton interactions, f super((D)) sub(DP), has been measured through the p sub(T) balance between the two jets and amounts to f super((D)) sub(DP) = 0.08+ or -0.01 (stat.)+ or -0.02 (sys.) for jets with transverse momentum p sub(T) > 20 GeV and rapidity |y| < 2.8. This corresponds to a measurement of the effective area parameter for hard double-parton interactions of sigma sub(eff) = 15+ or -3 (stat.) super(+5) sub(-3) (sys.) mb.
Despite the relationship between urbanization, energy use and CO2 emissions has been extensively studied in recent years, little attention has been paid to differences in development stages or income ...levels. Most previous studies have implicitly assumed that the impact of urbanization is homogenous for all countries. This assumption can be questionable as there are many characteristic differences among countries of different levels of affluence. This paper investigates empirically the effects of urbanization on energy use and CO2 emissions with consideration of the different development stages. Using the Stochastic Impacts by Regression on Population, Affluence and Technology (STIRPAT) model and a balanced panel dataset of 99 countries over the period 1975-2005, the findings suggest that the impact of urbanization on energy use and emissions varies across the stages of development. Surprisingly, urbanization decreases energy use in the low-income group, while it increases energy use in the middle- and high-income groups. The impact of urbanization on emissions is positive for all the income groups, but it is more pronounced in the middle-income group than in the other income groups. These novel findings not only help advance the existing literature, but also can be of special interest to policy makers and urban planners.
This study estimated energy use flow of buffalo farms, energy use indices, production efficiency, energy use targets, impact of energy inputs on energy output, and sensitivity analysis of energy ...inputs. A well-structured questionnaire was used to collect data of 360 domestic buffalo farms from Punjab Pakistan during May–July 2017. Results revealed that milk production was mainly dependent on renewable energy inputs, particularly millet, minerals, concentrates, and sorghum. Energy use efficiency (0.08) and production efficiency (0.24) indicate that energy inputs were overused. An artificial neural network (ANN) method suggested that 30.5% of total energy input could be saved if farmers followed the targeted inputs recommended by ANN. The Cobb-Douglas production function found a negative significant impact of sorghum, millet, and wheat straw; and positive significant impact of labour, concentrates, and electricity on energy output. Among the non-renewable energy sources, electricity was found to be the most wasteful use of energy input, mainly due to the mismanagement of farmers. Sensitivity analysis estimated that a unit increase in renewable energy significantly decreased milk yield by 0.02 unit. While a unit increase in non-renewable energy significantly increased milk yield by 0.01 unit. This study stresses the importance of using energy inputs at the target quantities prognosticated by ANN method, and recommends the use of energy-efficient equipment.
•Energy mismanagement is common problem in livestock production system of Pakistan.•Artificial neural network (ANN) method was used to optimize energy inputs.•Renewable energy inputs were overused for milk production in the study area.•Electricity was overused by 28.2% mainly due to farmers' mismanagement.•ANN suggested 33% improvement in energy ratio by using target values of energy inputs.
Buildings are a major contributor to climate change, accounting for one third of global energy consumption and one quarter of CO2 emissions. However, comprehensive information is lacking for the ...development, evaluation and monitoring of mitigation policies. This paper discusses the remaining challenges in terms of reliability and consistency of the available data. A review of energy use in buildings is presented to analyse its evolution by building types, energy services and fuel sources. Residential buildings are the most consuming, although tertiary expansion requires further analysis to develop sound specific indicators. Heating Ventilation and Air Conditioning (HVAC) systems concentrate 38% of buildings consumption, calling for strengthened standards and incentives for retrofitting. Electrification is rapidly increasing, representing a potential tool for climate change mitigation, if renewable power was promoted. However, energy use in buildings will only curb if global cooperation enables developing nations to break the link between economic growth, urbanisation and consumption. To this aim, efficiency gains both in construction and equipment, decarbonisation of the energy mix and a global awareness on energy conservation are all needed.
•Buildings account for a third of global consumption and a quarter of CO2 emissions.•HVAC accounts for 38% of buildings consumption, equivalent to 12% of final energy.•Population, wealth and urbanisation in emerging nations are the key upward drivers.•Energy intensity gains require retrofitting and adopting conservation behaviours.•Building’s electrification is far and pointless until the power sector is decarbonised
This paper reviews the discrepancy between predicted and measured energy use in non-domestic buildings in a UK context with outlook to global studies. It explains differences between energy ...performance quantification and classifies this energy performance gap as a difference between compliance or performance modelling with measured energy use. Literary sources are reviewed in order to signify the magnitude between predicted and measured energy use, which is found to deviate by +34% with a standard deviation of 55% based on 62 buildings. It proceeds in describing the underlying causes for the performance gap, existent in all stages of the building life cycle, and identifies the dominant factors to be related to specification uncertainty in modelling, occupant behaviour and poor operational practices having an estimated effect of 20-60%, 10-80% and 15-80% on energy use respectively. Other factors that have a high impact are related to establishing the energy performance target, impact of early design decisions, heuristic uncertainty in modelling and occupant behaviour. Finally action measures and feedback processes in order to reduce the performance gap are discussed, indicating the need for energy in-use legislation, insight into design stage models, accessible energy data and expansion of research efforts towards building performance in-use in relation to predicted performance
Compared to a century ago, the world's fishing fleets are larger and more powerful, are travelling further and are producing higher quality products. These developments come largely at a cost of ...high‐fossil fuel energy inputs. Rising energy prices, climate change and consumer demand for ‘green’ products have placed energy use and emissions among the sustainability criteria of food production systems. We have compiled all available published and unpublished fuel use data for fisheries targeting all species, employing all gears and fishing in all regions of the world into a Fisheries and Energy Use Database (FEUD). Here, we present results of our analysis of the relative energy performance of fisheries since 1990 and provide an overview of the current state of knowledge on fuel inputs to diverse fishing fleets. The median fuel use intensity of global fishery records since 1990 is 639 litres per tonne. Fuel inputs to fisheries vary by several orders of magnitude, with small pelagic fisheries ranking among the world's most efficient forms of animal protein production and crustaceans ranking among the least efficient. Trends in Europe and Australia since the beginning of the 21st century suggest fuel use efficiency is improving, although this has been countered by a more rapid increase in oil prices. Management decisions, technological improvements and behavioural changes can further reduce fuel consumption in the short term, although the most effective improvement to fisheries energy performance will come as a result of rebuilding stocks where they are depressed and reducing over‐capacity.
This study investigates the short-term and long-term impacts of economic growth, trade openness and technological progress on renewable energy use in Organization for Economic Co-operation and ...Development (OECD) countries. Based on a panel data set of 25 OECD countries for 43 years, we used the autoregressive distributed lag (ARDL) approach and the related intermediate estimators, including pooled mean group (PMG), mean group (MG) and dynamic fixed effect (DFE) to achieve the objective. The estimated ARDL model has also been checked for robustness using the two substitute single equation estimators, these being the dynamic ordinary least squares (DOLS) and fully modified ordinary least squares (FMOLS). Empirical results reveal that economic growth, trade openness and technological progress significantly influence renewable energy use over the long-term in OECD countries. While the long-term nature of dynamics of the variables is found to be similar across 25 OECD countries, their short-term dynamics are found to be mixed in nature. This is attributed to varying levels of trade openness and technological progress in OECD countries. Since this is a pioneer study that investigates the issue, the findings are completely new and they make a significant contribution to renewable energy literature as well as relevant policy development.
•Economic growth, trade openness and technological growth drive renewable energy use.•Long-term dynamics of the variables are found homogenous across the OECD countries.•Short-term dynamics vary as to variation in technological growth and trade openness.•An understanding of variable dynamics is vital for increasing renewable energy use.
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