85 research outputs found

    A Simulation of daylight levels for the determination of visual comfort in large spaces

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    In sizable environments, such as the collective areas of a big university building, characterised by very long corridors, large hallways and broad glazed surfaces, the daytime illumination factor is often only excellent near to the latter, due to their predominantly horizontal, rather than vertical, nature. His study, which has been carried out thanks to a simulation software, shows the results of a correlation between light contributions, come out from the wide glass surface and those of a big skylight which cross lenghtways the main part of the building. Such results have been compared with some instrumental measurements considering the shifting and getting from them important informations on simulations reliability

    RESEARCH ON MICROCLIMATE LIGHT CONDITIONS IN A SCHOLASTIC ENVIRONMENT, BASED ON ADAPTIVE MODEL

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    This paper shows the results of a deep research, carried out on a scholastic setting and based on a questionnaire, to evaluate the light microclimate and the satisfaction degree of the users. Through simulations, we have previously identified a number of classrooms where the conditions could be critical, both in terms of over-lightning, glare and disrespected values (suggested by the current normative). The proposed method consist in using device-made-surveys, a simulation software and questionnaires submission to users of the studied rooms. The questionnaires, based on an adaptive model, has been developed to detect subjective data (place, visus…) and other information about the setting and its relationship with the users (difficulty in eyesight, year average frequency using light shelf. The results obtained after the questionnaires’ submission, mapped in a chromatic scale that considers each position held by every users, show high degrees of dissatisfaction even if the device-madesurveys has found values considered quantitatively acceptable. Another simulation shows the possibility of corrective actions, not invasive, in order to control natural light, which results shows a quantitative values reduction from the optimal range followed by a significant improvement in terms of quality of the microclimate light conditions. The procedure we developed derives by the integration of traditional and experimental methods, evaluating the gap that, in this case, seemed to be too high considering the whole school time

    Evaluation through adaptive model (ATC) in the levels of thermal comfort in summer in offices in Mediterranea locations.

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    The design of the building-plant system in the case of office buildings has rarely considered the adaptive model of comfort almost always limited to the control of temperature and humidity and only in some cases of PMV and PPD. Specifically when the building interacts with a climate characterized by high values of external temperature and humidity for long periods, and with high solar radiation in the presence of large glazed areas, it is crucial to take into account relevant aspects of the principle of thermal adaptation. The long stay of the occupants in an air-conditioned environment leads, at the request of colder temperatures very distant from those indicated by the criteria of acceptability of an environment from those occurring at the same moment outside the building, characterizing in this way, a greatly exceeding to negative values with respect to static model of comfort. By using of the adaptive model, the occupant of a building is no longer simply understood as a passive subject, as it appeared in the static model of Fanger, but as an active agent that interacts at all levels with the environment in which stays. This article shows an experimental study, which shows that the results of this model defines comfort temperatures greater and more flexible than the model of Fanger, even with significant energy savings on air conditioning in summer

    Thermo-hygrometric comfort in the lecture hall of a library: methodology and experimental evidence.

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    The present study verifies the thermo hygrometric comfort conditions in subjects of a university library users, evaluating the differences and peculiarities in the data collected at the measurement campaign. Particularities of the investigation is the period studied concerning the time frame of the Middle season, which is not expected to power the air conditioning systems. Based on assumptions on the thermal resistance of clothing in the spring and the metabolic type of subjects, the environmental parameters were monitored in some work position in the reading hall in the library of the Faculty of Medicine and Surgery of the University of Palermo. The article presents analyses of the measured data correlating the passive structure behavior and the variation of the internal temperature increases caused by the occupants and by the external temperature gradient. These results are compared with the limits and the guidelines provided by legislation for the main variables measured and derived, and which constitute the essential support to test the tolerability of the occupiers against the thermal environment with which they interact. Keywords: PMV PPD Indexes, Thermo-hygrometric comfort, acceptability classes

    Regional policies for sustainability in the Mediterranean countries: the role of a proper HVAC system maintenance in museums

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    Italy, like several Mediterranean countries, holds a very large number of cultural artifacts that are often exhibited and saved inside museums. Museums are usually part of historical buildings that, not rarely, originally had a different intended use and that have been currently transformed in place for conservation and for exhibition of works of art. The use of historical buildings as museums leads to limitations in the management and distribution of exhibition space, in design and managing HVAC systems and in the achievement of targets relating to the continuous monitoring of the microclimate for people comfort and for preservation of works of art. Moreover, the costs of the operation and maintenance of the HVAC system for this particular type of confined environment are often very expensive and the proper optimization of the required operations plays a main role. In this paper, authors propose a new decision support tool for curators regarding the operation and maintenance management of HVAC systems in museums especially in the case of their belonging to cultural heritage buildings

    Urban Waste As Resource For Sustainable Environment

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    The emerging model of waste disposal, develops an integrated approach based on waste reduction, selection, recycling, energy recovery and residual use of landfill. Here we discuss the fundamentals of a proper planning of waste disposal system, specially the thermal recovery, the integration and the methodological approach, either from the environmental and economic point of view. The growing demand for energy, the resulting environmental problems due to satisfy the demand for energy and the complex-economic system, necessitate the study of new technologies such as energy from municipal solid waste (MSW) obtaining as a result of decrease huge mass of solid waste to sanitary landifill and emissions of landifill gas as (CH4 and CO2 ). Therefore, we propose to validate a technical, economical and environmental analysis of waste-treatment systems with enphasis on generation of energy. The recovery of heat from a waste-to-energy plant, can make a useful contribution to the city energy needs. Whilst we have been slow to exploit fully this resource in Sicily, economically in urban areas

    A Mathematical Model For Evaluating Energy Consumptions In Life Cycle Assessment.

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    This paper takes up the ecobalance topic giving prominence to a calculation procedure of necessary energy consumptions for the production of a product in the different phases of a whole life cycle. Are used to identify all stages of the life cycle are determined and simplified formulas for the calculation of specific energy consumption. Is also examined a case where the components of the final product are up to 8. The model is valid for any type of product and through operations research (ie, placing constraints on the variables) you could get to optimal solutions minimizing the objective function

    Extracellular vesicles in airway homeostasis and pathophysiology

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    The epithelial–mesenchymal trophic unit (EMTU) is a morphofunctional entity involved in the maintenance of the homeostasis of airways as well as in the pathogenesis of several diseases, including asthma and chronic obstructive pulmonary disease (COPD). The “muco-microbiotic layer” (MML) is the innermost layer of airways made by microbiota elements (bacteria, viruses, archaea and fungi) and the surrounding mucous matrix. The MML homeostasis is also crucial for maintaining the healthy status of organs and its alteration is at the basis of airway disorders. Nanovesicles produced by EMTU and MML elements are probably the most important tool of communication among the different cell types, including inflammatory ones. How nanovesicles produced by EMTU and MML may affect the airway integrity, leading to the onset of asthma and COPD, as well as their putative use in therapy will be discussed here
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