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This paper describes the results of experimental tests and computer simulation modelling aimed at evaluating the performance of an electrochromic (EC) window with respect to solar radiation control and the relative impact on the energy consumption of buildings of the residential type for two typical Italian climates. The research is carried out by a test-cell equipped with a small area EC double glazing unit and by a simulation program of buildings’ energy behaviour in transient regime. The experimental results show that EC devices which modulate solar radiation mainly by absorption, like the one investigated in this paper, generate secondary solar heat gains which entails a 20% decrease of the maximum potential energy flux reduction. Also, this effect could rise the temperature of the internal glass pane of the glazing to levels for which risk of thermal discomfort for the occupants may occur. The computer simulation modelling involves a residential building unoccupied during a large fraction of daytime in weekdays. The savings potential of the investigated EC window are calculated relative to a conventional clear float double glazing unit. Results show that the EC glazing may lead to a considerable decrease of the cooling energy demand (and of the total building energy consumption) in cooling dominated climates. The energy saving benefits become less marked in heating dominated climates and, for low values of the window-to-wall ratio, can be overcame by the increase in lighting and heating energy requirements that results in an increase of the total building energy demand. [ABSTRACT FROM AUTHOR]

Abstract: Sandstones quarried in the Firenzuola district (Florence, Italy) have been investigated in order to evaluate their outdoor durability. We have studied the relationships between mineralogical, petrographical, physical and mechanical properties. The sandstones from Firenzuola are characterized by a heterogeneity of mineralogical, petrographical characteristics that strongly affected the physical and mechanical properties. Simulation of different environmental conditions has been performed using accelerating ageing tests (freeze/thaw, salt crystallization, acid rains) and a comparison with the real cases of use of this stone in the urban, marine and mountain environments is proposed. This paper highlights how the mineralogical and petrographical characteristics affect the physical and mechanical properties: the presence of a high amount of carbonatic cement determines a low effective porosity; a prevalence of small pores and a high value of uniaxial compressive strength, while a high amount of clay matrix determines high effective porosity; a prevalence of larger pores and a low uniaxial compressive strength. These parameters, in turn, determine a different proneness of this material to decay. The most relevant cause of decay for these sandstones is salt crystallization, which determines a decrease in mechanical properties. This paper also stresses the need for new standard methodologies for evaluating the tendency to decay of superficial portions of material such as the analyzed pavements. [Copyright &y& Elsevier]

Abstract: FERMI@elettra is a fourth-generation light source user facility under construction at the Elettra Laboratory in Trieste, Italy. The high-quality 1.2GeV electron beam drives two-seeded Free Electron Lasers (FELs) in the wavelength range 100−10nm. Wavelength tunability, variable polarization and higher electron beam energies to reach even shorter output wavelengths are also in the machine delivery plan. This paper describes the physics processes that have been modelled to simulate FERMI@elettra and the computer codes used to optimize the machine design. The paper focuses on several design challenges and how these translate into modelling and simulation challenges. [Copyright &y& Elsevier]

Climatic conditions strongly affect the energy performance of buildings, and due to the synergy between global climate change and the Urban Heat Island (UHI) effect, the climatic conditions inside and outside the city are highly different. However, weather data collected at airports are commonly used for building energy simulations and these data do not take into account real temperature distribution in cities. Many studies in the literature address the topic but mostly considering only a couple of urban and non-urban stations. In this paper, the urban climate in Rome, Italy, is analysed after monitoring of the air temperature and relative humidity in four selected neighbourhoods and one reference station from October 2014 until September 2017. Rome is characterised by a composite urban pattern and high variability of building types, of which the four selected areas are representative. The heating degree days decrease up to 18% and cooling degree days increase up to 157% in the urban area with respect to the rural reference and the area most affected by the UHI is the city centre. The UHI is more intense in summer than in winter (average increase between 0.7 °C and 1 °C); while the diurnal and nocturnal UHI depends on the season and the neighbourhood. Then, the energy performance of a representative apartment block and a typical office building was computed using the measured data. Regarding the predicted energy performance, comparing the four urban sites and the reference site, the UHI causes a reduction of heating consumption up to 21% in residential building and 18% in the office building. An increase of cooling consumption up to 74% is instead computed for the residential building and up to 53% for the office building. [ABSTRACT FROM AUTHOR]

In this paper we show 3D physics-based numerical simulations of ground motion during one of the most devastating earthquakes in the recent Italian history, occurred on Jan 13, 1915, Marsica, Central Italy. The results provide a realistic estimate of the earthquake ground motion and fit reasonably well both the geodetic measurements of permanent ground settlement, and the observed macroseismic distribution of damage. In addition, these results provide a very useful benchmark to improve the current knowledge of near-source earthquake ground motion, including evaluation of the best distance metrics to describe the spatial variability of the peak values of ground motion, the relative importance of fault normal vs fault parallel components, the conditions under which vertical ground motion may prevail, as well as the adequacy of 1D vs 3D modelling of site amplification effects. [ABSTRACT FROM AUTHOR]

In this paper, the airflows developing in a room devoted to the wine-aging process are numerically predicted. A real study case is investigated, regarding an Italian company operating in the wine sector. The airflow is modeled by adopting the lattice Boltzmann method. Specifically, large eddy simulations are performed through the Smagorinsky turbulence model. In order to account for the presence of walls and barrels, the Immersed Boundary method is used. Scenarios characterized by different layouts of the room are investigated, showing the incidence of an extra opening in the room on the whole air circulation. Present findings can be successfully used by wine-makers, since these provide the effectiveness of a numerical framework which predicts the developing of the airflow. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, we present an ongoing project, named Talking Museum and developed within DATABENC - a high technology district for Cultural Heritage management. The project exploits the Internet of Things technologies in order to make objects of a museum exhibition able to “talk” during users’ visit and capable of automatically telling their story using multimedia facilities. In particular, we have deployed in the museum a particular Wireless Sensor Network that, using Bluetooth technology, is able to sense the surrounding area for detecting user devices’ presence. Once a device has been detected, the related MAC address is retrieved and a multimedia story of the closest museum objects is delivered to the related user. Eventually, proper multimedia recommendation techniques drive users towards other objects of possible interest to facilitate and make more stimulating the visit. As case of study, we show an example of Talking museum as a smart guide of sculptures’ art exhibition within the Maschio Angioino castle, in Naples (Italy). [Copyright &y& Elsevier]

Abstract: In this paper we present a high resolution assessment of the wave energy resources in the Mediterranean. The energy resources are evaluated through of a numerical simulation performed on the entire Mediterranean basin for the period 2001–2010 using a third generation ocean wave model. The model results are extensively validated against most of the available wave buoy and satellite altimeter data. Starting from the model results a detailed analysis of wave energy availability in the Mediterranean Sea is carried out. The western Sardinia coast and the Sicily Channel are found to be among the most productive areas in the whole Mediterranean. Simulation results show the presence of significant spatial variations of wave power availability even on relatively small spatial scales along these two coastlines. For a number of selected locations in these two areas we present an in-depth investigation of the distribution of wave energy among wave heights, periods and directions. Seasonal and inter-annual variability of wave energy potential are also analyzed and discussed. [Copyright &y& Elsevier]

Abstract: This paper presents the assessment of a NDVI-based parametric model (C-Fix) and a bio-geochemical model (BIOME-BGC) for the simulation of semi-natural grassland primary productivity in Italy. The two models are first calibrated using the gross primary productivity (GPP) data of an eddy covariance flux tower placed over a Mediterranean-temperate hilly area in Central Italy. Next, they are applied to estimate the net primary productivity (NPP) of three independent areas representative of different eco-climatic zones. The first area shows a typical Alpine climate, while the other two are characterized by more or less pronounced Mediterranean features. The accuracy of the NPP estimates is assessed through comparison with destructive dry matter measurements taken in the three areas. The results obtained support the capability of the two models to predict spatial NPP differences across the various grassland sites. The greatest estimation errors are found in the mountain area, mostly due to inaccuracies in the meteorological input data. These errors affect particularly the outputs of the bio-geochemical model and are mitigated by the use of C-Fix, which exploits the remotely sensed information related to the seasonal evolution of green biomass. [Copyright &y& Elsevier]

Abstract: Artificial Neural Networks (ANNs) have been successfully employed for predicting and forecasting groundwater levels up to some time steps ahead. In this paper, we present an application of feed forward neural networks (FFNs) for long period simulations of hourly groundwater levels in a coastal unconfined aquifer sited in the Lagoon of Venice, Italy. After initialising the model with groundwater elevations observed at a given time, the developed FNN should able to reproduce water level variations using only the external input variables, which have been identified as rainfall and evapotranspiration. To achieve this purpose, the models are first calibrated on a training dataset to perform 1-h ahead predictions of future groundwater levels using past observed groundwater levels and external inputs. Simulations are then produced on another data set by iteratively feeding back the predicted groundwater levels, along with real external data. The results show that the developed FNN can accurately reproduce groundwater depths of the shallow aquifer for several months. The study suggests that such network can be used as a viable alternative to physical-based models to simulate the responses of the aquifer under plausible future scenarios or to reconstruct long periods of missing observations provided past data for the influencing variables is available. [Copyright &y& Elsevier]

Abstract: This paper describes the application of a methodology for the evaluation of debris-flow risk in alluvial fans by incorporating numerical simulations with Geographical Information Systems to identify potential debris-flow hazard areas. The methodology was applied to a small catchment located in the north-eastern part of Sicily, Italy where an extreme debris flow event occurred in October 2007. The adopted approach integrates a slope stability model that identifies the areas of potential shallow landslides under different meteorological conditions using a two-dimensional finite-element model based on the De Saint Venant equation for the debris-flow propagation. The mechanical properties of the debris were defined using both laboratory and in situ test results. The risk classification of the area under study was derived using total hydrodynamic force per unit width (impact pressure) as an indicator for event intensity. Based on the simulation results, a potential risk zone was identified and mapped. [Copyright &y& Elsevier]

Abstract: This paper summarizes the results of an extensive experimental study aiming to evaluate the performance and pollutant emissions of diesel and CNG waste collection trucks under realistic and controlled operating conditions in order to support a fleet renewal initiative in the city of Milan. Four vehicles (1 diesel and 3 CNG) were tested in two phases using a portable emission measurement system. The first phase included real world operation in the city of Milan while the second involved controlled conditions in a closed track. Emissions recorded from the diesel truck were on average 2.4kg/km for CO2, 0.21g/km for HC, 7.4g/km for CO, 32.3g/km for NOx and 46.4mg/km for PM. For the CNG the values were 3.6kg/km for CO2, 2.19g/km for HC, 15.8g/km for CO, 4.38g/km for NOx and 11.4mg/km for PM. CNG vehicles presented an important advantage with regards to NOx and PM emissions but lack the efficiency of their diesel counterparts when it comes to CO, HC and particularly greenhouse gas emissions. This tradeoff needs to be carefully analyzed prior to deciding if a fleet should be shifted towards either technology. In addition it was shown that existing emission factors, used in Europe for environmental assessment studies, reflect well the operation for CNG but were not so accurate when it came to the diesel engine truck particularly for CO2 and NOx. With regard to NOx, it was also shown that the limits imposed by current emission standards are not necessarily reflected in real world operation, under which the diesel vehicle presented almost 4 times higher emissions. Regarding CO2, appropriate use of PEMS data and vehicle information allows for accurate emission monitoring through computer simulation. [Copyright &y& Elsevier]

Abstract: Parabolic trough collectors were investigated, applying the study results to a plant prototype installed in Florence (Italy) for residential supply. Ray tracing simulations examined optical characteristics and collection performance on the base of prototype geometry and functionality. The purpose was to control the realisation errors and overcome the difficulties arising in the development of the solar trough plant. The paper summarises the results of several studies analysing the interactions between collection efficiency, angular misalignments, mirror deformations, sun tracking and trough placement. The mirror deformations are reproduced introducing an original procedure. The unusual subject of imprecision in trough axis placement is discussed. [Copyright &y& Elsevier]

Abstract: An unusually intense subsynoptic-scale cyclone has been documented in southeastern Italy on 26 September 2006. Numerical simulations are performed with the Weather Research and Forecasting model (WRF). Model results show that the model is able to realistically capture the timing and intensity of the cyclone, identifying in this small-scale cyclone the typical characteristics of a Mediterranean tropical-like cyclone. Sensitivity experiments to sea surface temperature (SST) of the simulated cyclone are discussed in the present paper. In these experiments the SST was changed by a constant few degrees uniformly throughout the Mediterranean Sea. The simulated-cyclone sensitivity to SST is studied in the framework of an air–sea interaction theory, in particular during the two phases that are fundamental for the development of an environment favorable to severe convection and thus for the cyclone to be self-sustained. The modifications of the properties of the simulated cyclones are then analyzed using an objective evaluation, based on a phase diagram used to study the tropical–extratropical transition of cyclones. The present simulations show that the features typical of a tropical cyclone are progressively lost as the SST is reduced. In the colder SST experiments, the lower intensity of the sea-surface fluxes has the effect of delaying and reducing the development of convection and the intensification of the cyclone, so that the cyclone loses the characteristics of a tropical cyclone when SST is reduced by more than 4°C. On the other hand, the cyclone shows a pressure minimum deeper than the control run, with a persistent symmetric warm core, for SST increased by more than 2°C. Finally, when SST is changed by less than 2°C, the cyclone depth and trajectory are not significantly affected by the change in SST and, like the control run, show tropical-like features only for a limited period. [Copyright &y& Elsevier]

Abstract: A new geoid computed with high-resolution for Italy, is presented in this paper. The computation of this gravimetric geoid is based on the most recent geopotential model: EGM2008 (Earth Gravity Model released in 2008). The method used in the computation of this new gravimetric geoid has been the Stokes integral in convolution form. The terrain correction has been applied to the gridded gravity anomalies, to obtain the corresponding reduced anomalies. Also the indirect effect has been taken into account. Thus, a new geoid model has been calculated and it is provided as a data grid in the Geodetic Reference System of 1980 (GRS80), distributed for the study area from 37° to 48° of latitude and 6° to 19° of longitude, on a 441×521 regular grid with a mesh size of 1.5′×1.5′. This new high-resolution geoid and the global geoid EGM2008; are compared with the geoid undulations measured for 11 points of the EUropean Vertical Network (EUVN) on Italy. The new geoid shows an improvement in precision and reliability, fitting the geoidal heights of these EUVN points with more accuracy than the global geoid. Moreover, this new geoid has a smaller standard deviation (12.5cm) than that obtained by any previous geoid developed for Italy (and the surrounding area) up to date (). This new model will be useful for orthometric height determination by GPS over this study area, because it will allow orthometric height determination in the mountains and remote areas, in which levelling has many logistic problems. This new model can be also interesting for other geophysical purposes, other than geodesy and the height measurements, because it can provide a constraint for the density distribution and the thermal state of lithosphere and the viscosity in the mantle. Such details can be inferred from a geoid model and the seismic velocity structure. [ABSTRACT FROM AUTHOR]

Abstract: In this paper we exploit the dynamic allocation scheme for input redundant control systems proposed in to achieve elongation control on FTU (Frascati Tokamak Upgrade). The scheme first serves as a means for regulating the current in the F coils. Then, due to the quasi-static relationship between the plasma elongation and the F coils current, elongation control is achieved by suitably generalizing the allocation scheme. Both simulation and experimental results are reported. [ABSTRACT FROM AUTHOR]

Abstract: In the present paper some numerical simulations and experiments were carried out to study jet-wall interaction in shallow waters. Namely, modifications of the hydrodynamic field concerning the interaction of river run-off with a shallow coastal water body, due to the presence of marine structures, were investigated. Stratification effects due to salinity and temperature were neglected, and the interest was focused on barotropic features (Coanda effect). The numerical analysis was carried out by means of shallow water equations, numerically solved by finite difference, and the present method was validated by means of a typical simple-shaped test case. The experiments were carried out in a shallow water tank, flow visualizations were performed, and the velocity field was obtained by PIV. The main features of jet-wall interaction flow were investigated in simple-shaped geometries, and applications were shown for two practical cases: Pescara channel harbour (Adriatic Sea, Italy) and the proposed design of Latina harbour (Tyrrhenian Sea, Italy). [Copyright &y& Elsevier]

Abstract: The seismic analysis of a large monument subjected to strong earthquakes is the object of the present paper. As a case study, the response of the “Maniace Castle” of Syracuse has been investigated by a multi-level approach which adopts traditional finite element modelling as well as a specific mechanistic computational model for the final non-linear seismic analyses. At first, the linear behaviour of the monument was studied by means of two 3D FE models in order to understand the global response of the building, its points of weakness, and the kinematics of the corresponding collapse mechanisms. Then, these results were used to calibrate a mechanistic 2D plane rigid body and spring model, RBSM, specifically formulated with the aim of approximating the macroscopic behaviour of masonry walls with reduced degrees of freedom, and taking into account the influence of the masonry texture and energy dissipation capacity of the material. Given the uncertainties and the variability of the material characteristics, an extensive parametric non-linear static analysis and the dynamic analyses, with artificial and natural accelerograms, were made in accord with the EC8 seismic code, and compared together. These results were then used to formulate and verify a simple proposal for the restoration design. [Copyright &y& Elsevier]

Abstract: Some architectural structures inside historical buildings are often interpreted as cooling systems. The problem is the knowledge about the real functioning of these systems during the past and at the present. Full scale measurements can provide data on ventilation rate, airflow distribution, mean air velocity around and inside a building, but these experiments are really expensive and time consuming. In this paper, the airflow patterns, distribution and velocity and the air temperature distribution inside a historical building in Palermo (Italy) were investigated by a transient simulation. A three-dimensional model of the library room, actually used as book deposit, where an ancient natural ventilation system is operating, was investigated using a CFD tool during the hottest day of the summer of 2006 in Palermo. The simulation results are in agreement with the trends of air velocity and temperature of the experimental values measured during a test campaign. [Copyright &y& Elsevier]

Abstract: Mt. Etna in Sicily (Italy) is one of the best monitored basaltic volcanoes in the world due to the frequent eruptions from its summit and flanks. Routine monitoring carried out by Istituto Nazionale di Geofisica e Vulcanologia, Sezione di Catania, for surveillance purposes permits following the evolution of volcanic events. In this paper, a description of the ash monitoring system as occurred during the August–December 2006 summit eruption at the Southeast Crater (SEC) is shown. This eruption was characterized by lava flow effusions and vigorous Strombolian activity. Eighteen paroxysmal episodes occurred up to the end of November, forming weak ash plumes accompanied by moderate tephra fallout over Etna''s slopes. During these events, we applied a multidisciplinary approach to promptly monitor the paroxysmal activity and the associated tephra fallout, through analysis from seismic tremor and observation from live-cameras, sampling operations, mapping and analysis of the deposit. During the most significant episodes, we carried out textural and grain-size analysis on tephra samples and evaluated the total grain-size deposit and the erupted volume, while numerical simulations of tephra dispersal allowed better understanding eruptive dynamics. An example of this methodology is applied to the 16 November episode, during which seismic tremor furnished important constraints on the chronology. This paroxysmal eruption produced light fallout on the north-east sector of the volcano for about ten hours and a number of debris-avalanches over the slopes of the SEC cone. The erupted deposit was composed for the most part of lithic components and characterized by a total-size distribution centered on 2.2 Φ, while its total mass was evaluated 7×106 kg. On the whole, such integrated studies help to obtain information on magma fragmentation and eruptive mechanisms, to characterize the explosive styles shown by Etna and finally, to better approach the monitoring of imminent eruptions. [Copyright &y& Elsevier]

A sampling campaign was conducted in the city of Milan, Italy before and during a transportation strike in January 2004. This strike provided a unique opportunity to investigate the influence of public transportation on the air quality in a major metropolitan area. Twenty-four air samples were collected each day around the city on January 2nd, 7th and 9th. The samples were analyzed for methane, carbon monoxide, non-methane hydrocarbons (NMHCs), halocarbons and alkyl nitrates. Significant differences in the mixing ratios were observed among the three days of sampling, with January 2nd showing the lowest concentrations as a result of decreased activity in the city during the holiday season. January 9th showed the highest NMHC concentrations because of increased vehicular activity in the city due to a public transportation strike. This paper investigates the correlation between the increased number of vehicles and decreased air quality because of a reduction in public transportation. Computer simulations were able to reproduce measurements of ozone production during the January 2004 strike and a July 2005 strike. The measurements and simulations suggest that reduced VOC emissions due to the existence of public transportation lowers peak ozone by 11–33% during the summer months. [Copyright &y& Elsevier]

• Precast RC shear wall structures have been largely built in Italy after WWII. • Most of these buildings have been designed with little or no attention to seismic issues. • Seismic assessment of these structures requires information on their ductility. • Careful FE analyses have been carried out to evaluate the ductility of several precast system. • Sensitivity and validation analysis have been performed to test the accuracy of FE models. This paper investigates the seismic behaviour of structural RC shear walls made with precast panels according to several proprietary technologies to build existing structures. The study focuses on determining the maximum ductility of these construction systems through in-plane lateral thrust numerical simulations by means of FE analysis. The investigations are carried out on three types of precast constructions systems, each one characterized by its own details and reinforcements, used to construct many buildings in central Italy between the early 70′s and the late 80′s. For reference and comparison purposes a coeval cast-in-place shear wall has been also analysed. The ductility values obtained from the analyses show that the shear walls made with these techniques have a similar or, in some cases, grater ductility than the cast-in-place shear walls built in the same period. In detail the lowest value of ductility, equal to 3.42, has been obtained by the cast-in-place shear wall while ductility values in the range 4.15–6.29, have been obtained by the three precast RC assemblies. The results of this research may provide a support for the seismic vulnerability analysis of existing buildings constructed with precast RC shear walls and may supply information for the behaviour factors estimation of this type of structures. [ABSTRACT FROM AUTHOR]

This paper analyses the performance of a multi-attribute auction for securing agri-environmental outcomes and cost-effective agri-environmental payments (AEPs). We set up a discriminatory price auction model in which farmers make an offer based on two attributes (i.e. the AEP and a proxy of environmental outcome). We provide a numerical simulation for a hypothetical agri-environmental scheme (AES) in Italy using FADN data 2011 for the Emilia-Romagna region (E-R). In three implementation scenarios, we compare the Budgetary cost-effectiveness (BCE), the Economic cost-effectiveness (ECE) and Information rent (IR) of the auction with that of two alternative policy instruments (i.e. uniform payment and marginal flat rate payment). Due to the heterogeneity in bidders' opportunity costs, the auction is more cost-effective than a uniform payment in delivering the target outcome. The performance indicators are sensitive to the farmers' expectations about the bid caps, revealing the opportunity of using both competition effect and information leverage associated with the implementation mechanism to increase the auction outcome when the budget is limited. • Reviews agri-environmental auction designs. • Simulates the performance of a multi-attribute auction for securing agri-environmental outcomes. • Applies an empirical methodology to derive farmers' compliance costs. • Analyses budgetary cost-effectiveness, economic cost-effectiveness and the information rent • Introduces independent bidders'' expectations and the joint acceptance probability rule. [ABSTRACT FROM AUTHOR]