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La letteratura scientifica evidenzia che la temperatura, la qualità dell’aria interna, la ventilazione, il rumore, la luce e la possibilità di controllare questi parametri individualmente influenzano le prestazioni umane. Per l’analisi dei costi-benefici degli edifici non è sufficiente avere dei dati che dimostrano l’influenza della qualità dell’ambiente interno sulla salute e sulle prestazioni lavorative, è necessario quantificarla. Per la temperatura e per la qualità dell’aria interna è stato possibile sviluppare relazioni quantitative circa i loro effetti. Le relazioni presentate hanno un elevato grado d’incertezza. Comunque, quando si progettano gli edifici e si scelgono le modalità operative è meglio utilizzare queste relazioni che ignorarne gli effetti sulla salute e sulle prestazioni poiché questi hanno un forte impatto economico. Un incremento dell’1% delle prestazioni lavorative può compensare completamente i costi annuali energetici. Gli interi costi di installazione ed esercizio di un impianto di condizionamento in un edificio possono essere compensati con un incremento della produttività del 10%. Usualmente il tempo di ritorno di un investimento per migliorare la qualità dell’ambiente interno è inferiore a due anni.L’obiettivo principale di questo lavoro è quello di presentare la traduzione della guida REHVA dedicata all’influenza del clima interno sulle prestazioni lavorative al fine di promuovere nei proprietari degli edifici, nei datori di lavoro, negli occupanti degli edifici e nei progettisti italiani la consapevolezza su questo argomento

La qualità degli ambienti interni può essere valutata chiedendo direttamente agli occupanti, attraverso opportuni questionari, un giudizio sul loro luogo di lavoro. Secondo ASHRAE, USGBC e CISBE questo è il metodo più efficace. Ora è disponibile una versione in lingua italiana del questionario più utiliz-zato negli Stati Uniti (versione demo: www. cbesurvey.org/survey/italian). Attualmente l’esecuzione del test è gratuita.

The scientific literature shows that the temperature, indoor air quality and venti¬lation, noise and light, and the possibility to control them individually does affect human performance. For cost-benefit analysis it is not sufficient to have information demonstrating a statistically-significant effect of the indoor environmental quality on health and work performance, the dose response relationship of the effect must be quantified. For the temperature, ventilation and indoor air quality was it possible to develop the quantitative relationships describing their effects on office work or sick leave. These relationships have a high level of uncertainty. However, using them is preferable to the current practice of ignoring the effects on health and performance when designing buildings and selecting building operation practices because they have a high economical impact. Usually an increment of 1% of productivity may offset the yearly energy costs. The full costs of installation and running the building can be offset by productivity gains of just under 10%. The pay-back time for investments to improve indoor environmental quality is generally below 2 years.The main aim of this paper is to present the Italian translation of the REHVA guidebook about indoor climate and productivity in offices in order to attract the attention of building owners, employees, employers and building designers on the effects of indoor environment on office work.

important cause for that is acknowledged in the human activity. Many research projects are performed at international level and many initiatives were defined, in order to manage the actions of Countries and avoid the irreversible environmental alteration. Then, several solutions have been conceived till now. Among them, renewable energy sources are designated to become really relevant. This paper deals with such a topic and is intended to show the present situation, both on the environmental and on the energy sides, in the field of heating and cooling of buildings. At first, the convenient use of renewable energy sources must start from energy efficiency actions. Moreover, the exploitation of renewable energy sources will push to adopt higher design expertise, since both buildings and national energy networks will be modeled in order to increase interactions and optimize the energy production and distribution.

Cooling energy savings and improved thermal comfort in hot climates can be achieved using cool roofing materials. High solar reflectance and infrared emittance values reduce the amount of absorbed solar radiation and the surface temperature of a material exposed to sun radiation, consequently the heat transfer into the building is lowered. A reduction of the urban heat island effect, caused by the presence of high absorption surfaces and the lack of vegetation, may be obtained using cool roofing materials.Computer energy simulations have been used to assess the energy savings and temperature profiles consequent to the application of a cool roofing material when applied to industrial premises in three Mediterranean cities: Genoa, Madrid and Cairo. In particular, the related influence on cooling energy demand and maximum temperature at the outside face of the roof are analyzed, varying the roofing material and the insulation thickness.The results of this study showed that using a cool roofing material in the Mediterranean area for industrial premises leads to significant sensible cooling energy savings, up to 42%. Moreover, it was obtained that the maximum roof outside surface temperatures decrease of 40÷50°C when cool roofing materials are applied.

Cause, conseguenze e strategie di mitigazione Proponiamo il primo di una serie di articoli in cui affronteremo l’attuale problema dei mutamenti climatici. Presentiamo il documento redatto, votato e pubblicato dall’Ipcc - Comitato intergovernativo sui cambiamenti climatici - che illustra la sintesi delle ricerche svolte su questo tema rilevante.

Politiche, misure e strumenti per contenere le emissioni di CO2 Illustriamo l’ultimo contributo al quarto Rapporto sui cambiamenti climatici votato a maggio 2007 dal terzo gruppo di lavoro del Comitato intergovernativo “Intergovernmental Panel on Climate Change”.Il Rapporto affronta la problematica delle tendenze delle emissioni dei gas serra e il tema della mitigazione a breve e lungo termine. Presentiamo un’analisi critica delle proposte del documento.

L’obiettivo di questo articolo è presentare, per quanto possibile in modo organico, semplice e obiettivo il tema del riscaldamento globale. Per la stesura dell’articolo ci si è basati fedelmente sul documento redatto, votato e pubblicato quest’anno dal comitato intergovernativo sui cambiamenti climatici (Intergovernmental Panel on Climate Change, IPCC). Esso rappresenta la sintesi, delle varie ricer- che svolte sul tema, che gode del consenso mondiale più ampio. Ci si è basati su tale documento poiché si desidera fornire ai professionisti dei dati condivisi dai più a livello mondiale, per poterli utilizzare nel loro lavoro e nelle loro argomentazioni. Si desidera inoltre stimolare, in modo costruttivo, l’interesse verso un problema che va a influenzare la nostra vita e quella delle generazioni future.

Impatti, adattamento e vulnerabilità Le cause e le responsabilità dei cambiamenti climatici sono state trattate sul numero di ottobre della rivista Cda. Approfondiamo l’argomento presentando il documento: “Cambiamenti climatici 2007: impatti, adattamento e vulnerabilità” votato ad aprile 2007 dal secondo gruppo di lavoro del Comitato Intergovernativo sui Cambiamenti Climatici (Intergovernmental Panel on Climate Change). Si tratta del secondo di tre documenti che compongono il quarto rapporto sui cambiamenti climatici.

Ground-coupled heat pumps are increasingly being utilized to heat and cool buildings. Although it is difficult to size and to predict their behavior and performance, their design can be optimized via simulations. EnergyPlus is a popular energy simulation program for modeling building heating and other energy flows and, since it is organized to consider borehole heat exchangers via the well-known g-functions approach, it can be used advantageously for that purpose. The Capacity Resistance Model is another recent numerical simulation tool devoted to ground and borehole heat exchangers. In this work, two methods to calculate the g-fucntions were analyzed, using as case-study a real office building, whose imbalance between the heat extracted and injected into the ground was found to be appreciable. The energy imbalance involves a ground temperature drift affecting the system efficiency. The results of the EnergyPlus g-functions and the Capacity Resistance Model model approaches were compared. The capacity of the two methodologies to accurately simulate this phenomenon were analysed also with reference to the available building's long-term monitoring data. The analysis showed the importance of using g-functions suitable to reflect the layout of the borehole field, in order to correctly evaluate the energy performance of the entire ground source heat pump system. [ABSTRACT FROM AUTHOR]

This study evaluates the indoor environmental conditions and children’s comfort levels in 8 classrooms in three Italian primary schools. It is a development of a pilot study previously carried out by the authors in other educational buildings. Spot and long-term measurements were made to evaluate microclimatic conditions (i.e. air temperature, relative humidity, CO2 concentration, and illuminance). A questionnaire, distributed three times, investigated the students’ perception of thermal and lighting comfort, their satisfaction with building-related factors, and their interactions with the environment. Predicted mean vote and predicted percentage dissatisfied indexes were calculated and an adaptive approach was also applied, but their results did not correspond to the students’ subjective evaluation of thermal comfort. An innovative multivariate ranking method was developed as a possible tool to assess building stocks in order to establish priorities for repair, maintenance, and refurbishment. The problem which the students complained about the most was the thermal comfort in the hot season and solar penetration. Moreover, the school with the worst microclimatic conditions was also judged the worst for building-related and psychological factors. [ABSTRACT FROM AUTHOR]

This article deals with the problem of classifying and ranking several multivariate populations of interests using the permutation and combination approach providing also an inferential validity of the procedure. The need to define an appropriate classification of populations, i.e., products, services, teaching courses, degree programs, and so on, is very common within many areas of applied research. Many times the populations of interest are multivariate in nature meaning that many aspects of that populations can be simultaneously observed on the same unit/subject. From a statistical point of view, when the response variable of interest is multivariate in nature, the problem may become quite difficult to cope with especially in case of ordered categorical responses, due to the large dimensionality of the parametric space. Nonparametric inference based on the NPC methodology however, allows us to overcome these limitations, without the need of referring to assume any specified random distribution. [ABSTRACT FROM PUBLISHER]

Ground coupled heat pumps are a notoriously efficient system for heating and cooling buildings. Sometimes the characteristics of the building and the user's needs are such that the amount of heat extracted from the ground during the winter season can be considerably different from the amount injected in summer. This situation can cause a progressive cooling or heating of the ground with a negative effect on the energy efficiency and correct operation of the system. In these cases, an accurate sizing has to be done. In systems already built, it could be necessary to intervene a posteriori to remedy an excessive ground thermal drift due to the energy unbalance. In this work, such a situation relating to a real office building in Italy is investigated and several solutions are examined, one of which has been then implemented. In particular, a hybrid heat pump using as heat sink both the ground and external air is compared with common solutions through computer simulations using a dedicated numerical model, which has also been compared with monitoring data. As a result, the hybrid heat pump shows better performance and limits the thermal drift of the ground temperature. [ABSTRACT FROM AUTHOR]