1,720,961 research outputs found
Urban Building Energy Modeling: an hourly energy balance model of residential buildings at a district scale
Full text linkThe energy consumption of buildings is related to several factors, such as the construction and geometric characteristics, occupancy, climate and microclimate conditions, solar exposure, and urban morphology. However, the interaction between buildings and the surrounding urban context should also be taken into consideration in energy consumption models. The aim of this work has been to create a bottom-up model in order to evaluate the energy balance of residential buildings at an urban scale, starting from the hourly energy consumption data. This modeling approach considers the building characteristics together with urban variables to describe the energy balance of the built environment; it can therefore be used to manage heterogeneous types of data at different scales and it can offer accurate spatial-temporal information on the energy performance of buildings. Detailed heat balance methods can be used at a building scale to estimate heating loads, but this urban-scale simplified model can also be used as a decision tool to support urban design explorations and for policy purposes.
This urban energy consumption model was verified for a case study of a district in Turin, Italy, with the support of a GIS tool, considering hourly energy consumption data of about 50 residential users for two or three consecutive heating seasons. The results show that a simplified model, based on low quality and quantity data, which are typical of an urban scale, can be a powerful tool for the evaluation and spatial representation of the energy needs of buildings at an urban scale
Urban-Scale Energy Models: the relationship between cooling energy demand and urban form
Full text linkTo enhance the quality of life in cities, it is necessary to improve the energy performance of buildings together with a sustainable urban planning especially in high-density contexts. Previous works investigated the building shape, the urban morphology, and the local climate conditions to optimize the energy performance for space heating of buildings. The aim of this study is to validate a GIS-based engineering model to simulate the hourly energy demand for space cooling in residential buildings at neighborhood scale and to assess the relationship between the urban form and the energy performance in terms of cooling energy demand. A place-based methodology was applied to six neighborhoods in the city of Turin (Italy), identified as homogeneous zones with different building characteristics and urban contexts. The hourly cooling demand of residential buildings was studied starting from the energy balance at building scale, and then was applied at block of buildings scale with the support of GIS. This model was
validated with a comparison of the results using CitySim tool and ISO 52016 assessment. In order to investigate the relationship between cooling energy demand and urban form, the GIS-based engineering model was applied to five typical blocks of buildings with different construction periods. The results show how cooling energy demand varies according to building characteristics and urban morphology in a continental-temperate climate. By this analysis, it is possible to identify the optimal block of building shape in Turin ensuring lower energy consumptions during the cooling season with different types of buildings
Building Efficiency Models and the Optimization of the District Heating Network for Low-Carbon Transition Cities
No full textNowadays, greenhouse gas emissions continue to increase with the consequent climate changes. Energy consumption of buildings strongly affects atmospheric pollution, therefore for a sustainable development it is necessary to adopt energy efficiency policies combined with low-carbon technologies. In particular, the use of district heating (DH) has environmental and economic advantages in energy production and distribution for space heating consumption. In this paper, the combined effect of DH expansion with different buildings retrofit scenarios using a GIS-based model is proposed for a more sustainable city.
This methodology is applied to the DH network of the city of Torino and, energy savings hypotheses were analyzed, evaluating different energy saving trends starting from the current one with existing policies. A GIS-based methodology has been developed with bottom-up and top-down approaches; then two future energy savings scenarios have been hypothesized. Energy retrofit measures have been applied to the most critical areas with low potential of heat distribution; in a second phase, to the whole area connected to the DH network. The results showed that intervening in the critical areas only +5% of potential buildings can be connected to the existing DH network (standard retrofit) while this percentage could grow up to +25% with advanced buildings retrofit. On the other hand, intervening on the whole city, there is a considerable reduction of consumptions and the connectable quota of buildings to the DH network reaches +42% with standard retrofit and +82% with advanced retrofit scenario with an optimization of energy distribution as well
Building energy models with morphological urban-scale parameters: A case study in Turin
No full textWith a growing awareness around the importance of the optimization of building efficiency, being able to make accurate predictions of building energy demand is an invaluable asset for practitioners and designers. For this reason, it is important to continually improve existing models as well as introduce new methods that can help reduce the so-called energy performance gap, which separates predicted from actual consumption values. This is particularly true for urban scale simulations, where even small scenes can be very complex and carry the necessity of finding a reasonable balance between precision and computational efforts. The scope of this work is to present two different models that make use of morphological urban-scale parameters to improve their performances, taking into account the interactions between buildings and their surroundings. In order to do this, two neighbourhoods in the city of Turin (IT) were taken as case studies. The buildings studied present similar characteristics but are inserted in a different urban context. Several urban parameters were extracted using a GIS tool and used as input, alongside the building-scale features, for two different models: i) a bottom-up engineering approach that evaluates the energy balance of residential buildings and introduces some variables at block-of-buildings scale, ii) a machine learning approach based on the bootstrap aggregating (bagging) algorithm, which takes the same parameters used by the previous model as inputs and makes an estimation of the hourly energy consumption of each building. The main results obtained confirm that the urban context strongly influences the energy performance of buildings located in high built-up areas, and that introducing simple morphological urban-scale parameters in the models to take these effects into account can improve their performance while having a very low impact on the computational efforts
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
- …
