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Residential natural gas consumption depends on several factors. Available tools and methods to identify, categorize, and validate effective factors have some limitations, making consumption modeling more complex. Once a comprehensive model of effective consumption factors is developed for residential gas consumers, it can predict consumption. In addition, such a model could be used to verify the accuracy of measuring devices in order to reduce unaccounted for gas (UFG). The key factors affecting residential gas consumption were identified based on previous studies and their mutual effects were analyzed using a fuzzy cognitive mapping (FCM) method. The most significant factors and their effects on natural gas consumption in the residential sector were determined. In this study, for the first time, the expected consumption for each consumer was estimated using a consumption index. Generally, if the estimated consumption is significantly different from the amount recorded by the meter, it could suggest a potential source of UFG. The proposed method was applied to the data collected from the residential gas consumers of a small region in Iran (Dasht-e Arjan region, Fars province), and the results demonstrate the effectiveness of the proposed method. 相似文献
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Human mobility prediction is of great advantage in route planning and schedule management. However, mobility data is a high-dimensional dataset in which multi-context prediction is difficult in a single model. Mobility data can usually be expressed as a home event, a work event, a shopping event and a traveling event. Previous works have only been able to learn and predict one type of mobility event and then integrate them. As the tensor model has a strong ability to describe high-dimensional information, we propose an algorithm to predict human mobility in tensors of location context data. Using the tensor decomposition method, we extract human mobility patterns with multiple expressions and then synthesize the future mobility event based on mobility patterns. The experiment is based on real-world location data and the results show that the tensor decomposition method has the highest accuracy in terms of prediction error among the three methods. The results also prove the feasibility of our multi-context prediction model. 相似文献
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One of the main reasons for the decline of urban historic areas in China is the co-existence of multiple property rights. It also deeply affects conservation and regeneration practice. This paper aims to propose a graphical method that illustrates the association between property rights, space, and resident behavior. Based on typological maps and justified graphs, a three-step method was proposed to visualize the relationships between these three elements. The final graph and quantitative data were used to observe the evolution of the courtyard building from a diachronic perspective, as well as to compare the residential behavior in different types from a synchronic perspective. The results show that following the subdivision of property rights, the building layout become more diverse due to various illegal additions, while the residential behavior within different building types tends to be consistent. Moreover, the study observed the traditional Chinese courtyard buildings’ adaptability. The findings contribute to understand the evolution of Chinese urban historic areas and internal motivation, and provide guidance for the conservation and regeneration practice. 相似文献
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《International Journal of Hydrogen Energy》2019,44(7):3891-3905
Residential Fuel Cell micro combined heat and power (FC-μCHP) systems can help decarburizing the energy system. In the European ene.field project, the environmental performance of FC-μCHP under different conditions was therefore evaluated by means of a comprehensive Life Cycle Assessment (LCA). Important influential factors were explored, i.e. heating demands, full load hours (FLHs) and electricity replacement mixes (ERMs). The systems were compared with a stand-alone Gas Condensing Boiler (GCB) and a heat pump (HP, only in single family homes, SFHs). For the initially assumed FLHs and the current ENTSO-E ERM, relevant environmental impacts including climate change are generally smaller for the FC-μCHPs than for the HP and the stand-alone GCB. In the setting “existing SFHs in central climate” with the highest deployment potential, GHG emission savings are higher the more carbon-intensive the ERM is and/or higher the net electricity export into the grid is. The results are discussed and put into perspective. Further research demands as well as product development opportunities are outlined. The importance of a green hydrogen economy is emphasized. 相似文献
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In one of two otherwise similar adjacent regions in a Canadian province, the price of electricity changed abruptly, substantially, and permanently. That natural experiment allows for a simple differences-in-differences calculation of the long-run price elasticity of residential demand for electricity. This analysis is of interest for two reasons. First, it is a rare circumstance when such a methodology can be used. Secondly, the magnitude of the elasticity estimate has substantial implications for utilities, regulators, and policymakers. 相似文献
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This study aims to explore the impact of light-duty passenger (LdP) electric vehicle (EV) charging on the Portuguese national load profile (LP) in 2030. The goal is to identify EV charging strategies that enable a sustainable configuration of the Portuguese LP under different potential levels of LdP EV penetration in 2030. The research offers Portuguese utilities and policymakers information regarding potential threats and solutions of different EV charging strategies on the national grid infrastructure in 2030. Furthermore, it proposes a methodology that can also be adopted in other countries to analyse similar problems. Low, medium, and high penetration scenarios were designated based on the number of LdP EVs. The low and medium penetration scenarios indicate that an intelligent grid is not necessary to perform charging activities. However, coordinating EV charging in the evening via a smart grid (SG) is imperative in the high penetration scenario, as unsustainable levels of power demand will otherwise be reached, compared with the current production and distribution capacity. Moreover, morning charging sessions must also be addressed, as they may induce new peaks of daily consumption given the significant amount of charging activity taking place within that period. 相似文献
8.
This study examines the effect of solar photovoltaic system installation on the electricity consumption in residential households across various geographic regions in San Diego. Using meter-level data, the electricity consumption for residential households is calculated before and after installation to assess whether there are any significant rebound effects in usage. Results reveal significant variations in the change in electricity usage depending on geographical location. The findings are relevant to regional resource planning and climate response, as the failure to account for the rebound effect may result in significant overestimation of the energy and emissions benefits of distributed renewable energy adoption. 相似文献
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