1,720,976 research outputs found
Energy Aspects of Urban Planning. The Urban Heat Island Effect
No full textThe research aims to analyze the tight relationship between the conformation of the city and the urban climate. The “heat island” phenomenon, typical of big urban centers, has a great impact on external temperatures, causing their increase compared to the surrounding rural areas. The study points out that the main factors responsible for such phenomenon are: the high percentage of built-up areas, the considerable presence of impermeable areas at the expense of the permeable ones, particularly green areas, the introduction of artificial heat in the atmosphere, generated by the combustion of hydrocarbon for transportations and domestic uses. Moreover a pivotal role is played by the urban canyons (which are generated by the geometrical configuration of the spaces among the buildings), the morphology of the urban tissue and the radiation properties (such as albedo and emissivity) of the surfaces. These considerations are confirmed by the results obtained in the experimentation conducted, in the city of Bari. Actually the results demonstrate that light color surfaces, with a higher level of albedo and wider green areas in some neighborhoods of Bari leads to a drop in temperatures of the external air, even of some degree days in the summertime.
The experimentation conducted outlines a guideline which considers the energy aspects of urban planning, thanks also to the possibility of realizing simulations by means of some particular software (suitable for the study of surfaces-vegetation-air interactions in the urban context) and to define different scenarios of project planning
Numerical and experimental computation of airflow in a transport container
No full textThe aim of this work is to perform a numerical and experimental analysis of convective flows inside an intermodal container refrigerated in hybrid mode, active by compressor and passive by eutectic plates, in the course of a simulated trip, in order to verify the distribution uniformity of the cold. This report shows the numerical simulation model implemented thanks to the use of Comsol Multiphysics 4.3b, a scientific commercial software CFD (Computational Fluid Dynamics) that allows thermofluidodynamic simulations. Two operation modes were considered in the model, one in laminar flow to reproduce the OFF cycle of the compressor with the only action of the eutectic plates, the other one in turbulent flow to reproduce the ON cycle of the compressor. In the second case, the k-ε model was used as a model of turbulence RANS (Reynolds Averaged Navier Stokes). The results of this numerical analysis were compared with experimental data acquired during the simulated trip to validate the implemented model
Numerical and experimental computation of airflow in a transport container
No full textThe aim of this work is to perform a numerical and experimental analysis of convective flows inside an intermodal container refrigerated in hybrid mode, active by compressor and passive by eutectic plates, in the course of a simulated trip, in order to verify the distribution uniformity of the cold. This report shows the numerical simulation model implemented thanks to the use of Comsol Multiphysics 4.3b, a scientific commercial software CFD (Computational Fluid Dynamics) that allows thermofluidodynamic simulations. Two operation modes were considered in the model, one in laminar flow to reproduce the OFF cycle of the compressor with the only action of the eutectic plates, the other one in turbulent flow to reproduce the ON cycle of the compressor. In the second case, the k-ε model was used as a model of turbulence RANS (Reynolds Averaged Navier Stokes). The results of this numerical analysis were compared with experimental data acquired during the simulated trip to validate the implemented model
Analisi numerico-sperimentale dei flussi convettivi all'interno di una cassa mobile refrigerata ibrida
Full text linkL’obiettivo di questo lavoro è effettuare un’analisi numerico-sperimentale dei flussi convettivi all’interno di una cassa intermodale refrigerata in modalità ibrida, attiva con il compressore e passiva con le piastre eutettiche, nel corso di un viaggio simulato, allo scopo di verificare l’uniformità della distribuzione del freddo. In questo rapporto è riportato il modello di simulazione numerica implementato grazie all’ausilio di Comsol Multiphysics 4.3b, un software commerciale scientifico CFD (Computational Fluid Dynamics) che permette simulazioni termofluidodinamiche. Nel modello sono state considerate le due
modalità di funzionamento, una in regime laminare per riprodurre il ciclo OFF del compressore con la sola azione delle piastre eutettiche, l’altra in regime turbolento per riprodurre il ciclo ON del compressore. In questo secondo caso come modello di turbolenza RANS (Reynolds Averaged Navier Stokes) è stato utilizzato il modello k-ε. I risultati di tale analisi numerica sono stati poi confrontati con i dati sperimentali acquisiti durante il viaggio simulato per validare così il modello implementato.The aim of this work is to perform a numerical and experimental analysis of convective flows inside an intermodal container refrigerated in hybrid mode, active by compressor and passive by eutectic plates, in the course of a simulated trip, in order to verify the distribution uniformity of the cold. This report shows the numerical simulation model implemented thanks to the use of Comsol Multiphysics 4.3b, a scientific commercial software CFD (Computational Fluid Dynamics) that allows thermofluidodynamic
simulations. Two operation modes were considered in the model, one in laminar flow to reproduce the OFF cycle of the compressor with the only action of the eutectic plates, the other one in turbulent flow to reproduce the ON cycle of the compressor. In the second case, the k-ε model was used as a model of turbulence RANS (Reynolds Averaged Navier Stokes). The results of this numerical analysis were compared with experimental data acquired during the simulated trip to validate the implemented model
L’ANALISI PER IL RECUPERO DELL’ARCHITETTURA PER SOTTRAZIONE IN BASILICATA. IL CASO DI PIETRAGALLA IN PROVINCIA DI POTENZA
No full textThe climatic heterogeneity that characterizes the Mediterranean area has lead men, which lived in those places since the antiquity, to modify and to adapt the land that surrounded them in order to create domestic or service spaces according to their needs and their comfort. It is so that to obtain bioclimatic rooms, as we call them today, the tufaceous walls have been excavated to realize hypogeal spaces, more or less extended, in which living or preserving the food, considering the constant temperature of the so obtained rooms, besides the particular humidity’s conditions. Are so obtained caves that if, on one hand, change the slope’s natural morphology thanks to the simple fact that are excavated works, on the other hand they marry with the landscape becoming almost invisibles. A good example is the rich town of Pietragalla, in Basilicata, in which is located a group of 200 tufaceous caves, distributed harmonically on more level’s shares. Today the Palmenti of Pietragalla are one of the evidences of rural productive centre of greatest importance of the lucan territory, in half way between rural and urban landscape, that must be preserved and recovered. Finished, in the majority of cases, the function for which they where realized, we ask on which are the compatible interventions for this kind of architecture, where the missing of a constant maintenance determine a quick ruin. The analysis of what has been shortly said, supported by a capillary documentary searching of the past interventions, besides a metric and material survey, has lead to the writing of a “practice code” for the compatible recovery of those very important evidences of the past
Analisi termografica su una cassa mobile refrigerata ibrida per il rilievo dei ponti termici
Full text linkL’obiettivo di questo lavoro è effettuare un’analisi termografica di una cassa intermodale refrigerata in modalità ibrida, attiva con il compressore e passiva con le piastre eutettiche, nel corso di un viaggio simulato, allo scopo di rilevare eventuali ponti termici sulle pareti della cassa, in corrispondenza di collegamenti od altre strutture di supporto. La cassa, durante le prove statiche, è stata portata in regime di freddo e quindi è iniziata la simulazione delle diverse fasi del viaggio gomma-nave-treno. I rilievi termografici outdoor della cassa mobile sono stati effettuati pertanto in diversi momenti, significativi del cambio della modalità di funzionamento, da più punti di ripresa, al fine di monitorare tutte le pareti della cassa mobile nelle diverse condizioni di viaggio. In questo rapporto sono riportati i risultati di tale analisi termografica ottenuti confrontando le riprese in digitale della cassa mobile con le relative termografie nelle varie fasi della prova statica.The objective of this work is to perform thermographic analysis of an intermodal container refrigerated in hybrid mode, active by compressor and passive by eutectic, in the course of a simulated trip, in order to detect any thermal bridges on the walls of the container, in correspondence of links or other support structures. During static test, once the container reached cold conditions, the simulation of the different phases of the road – ship – train trip began. The outdoor thermal images were therefore made at different and significant times, representative of the operating mode change, from several points of recording, in order to monitor all the walls of the container in the different travel conditions. This report shows the results of the thermographic analysis obtained by comparing the digital shootings
with its thermal images at various stages of the static test
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
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