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Accurate modeling of the patient flow within an Emergency Department (ED) is required by all studies dealing with the increasing and well-known problem of overcrowding. Since Discrete Event Simulation (DES) models are often adopted with the aim of assessing solutions for reducing the impact of this worldwide phenomenon, an accurate estimation of the service time of the ED processes is necessary to guarantee the reliability of the results. However, simulation models concerning EDs are frequently affected by missing data, thus requiring a proper estimation of some unknown parameters. In this paper, a simulation-based optimization approach is used to estimate the incomplete data in the patient flow within an ED by adopting a model calibration procedure. The objective function of the resulting minimization problem represents the deviation between simulation output and real data, while the constraints ensure that the response of the simulation is sufficiently accurate according to the precision required. Data from a real case study related to a big ED in Italy is used to test the effectiveness of the proposed approach. The experimental results show that the model calibration allows recovering the missing parameters, thus leading to an accurate DES model. [ABSTRACT FROM AUTHOR]

The agricultural sectors' contribution to the provision of energy is a central issue in Horizon 2020 strategies and has shaped the public and research debates on the future of the bioeconomy. The common agricultural policy (CAP) has been one of the main drivers of farmers' behavioural changes and represents the main agricultural policy instrument to address viability of rural areas and maintaining the profitability of the agricultural sector. To contribute to the ongoing policy debate towards CAP reform, this paper will provide an empirical model to simulate the impact of an alternative CAP mechanism on the provision of renewable energy. By applying a dynamic mathematical programming model, the paper tests the impact that new policy measures will have on the provision of a second-generation of bio fuel crops that represent a relevant option for Tuscan farmers. Results show that CAP reform positively impacts the supply of energy crops mainly due to the introduction of greening payments, which allows an enlarging of crop diversification. Model results stress also the income stabilisation effects of energy production introduction at farm level, due to reduction of farm exposure to market prices fluctuations. [ABSTRACT FROM AUTHOR]

This paper aims to critically examine the issue of rendering historic buildings energy efficient. Although this subject has been discussed to some extent on the national and international levels, it largely has been under-theorised as the existing literature focuses mainly on technical matters related to the improvement of energy performance. Indeed, one of the main issues which has not been thoroughly addressed in the literature is balancing conservation needs on the one hand and improved energy performance of historic buildings on the other, partly due to improper analytical tools, methods, and parameters that are commonly used to classify the energy behaviour of historic buildings. It is the matter of insufficient existing tools which triggered the development of this paper. This paper is based on experimental measurements in order to determine the most relevant parameters and the average thermo-physical data of the historic building envelope. The experiments were followed by evaluation of the energy performance of three listed buildings in Italy using static (used for energy certification in Italy), semi- dynamic, and dynamic computer simulations, in order to understand which energy audit schemes best simulate the actual energy performance of historic buildings while identifying the strengths and limitations of each type of software. The simulations were carried out using experimental data on the thermo-physical parameters of the building envelope components, energy bills, temperature, and relative humidity of air. The ultimate goal was to define the appropriate intervention for 'particular' types of historic buildings, in order to optimise the energy-efficiency requirements along with preservation of their inherent cultural values. [ABSTRACT FROM AUTHOR]

This paper addresses the master surgical scheduling problem. First, we present a mixed integer programming model. The model assumes that the cases in a hospital's waiting list can be classified into homogeneous surgery groups based on the resources (e.g. operating room, post-surgical beds) that they are expected to require. Hence, it produces a solution that indicates, for each day of the month and for each time slot of the day, the number of cases to treat and the surgery group these cases must belong to. The model maximizes the patient throughput, takes into account the cases' due dates and allows for control of the waiting list. Secondly, we illustrate the results of a simulation study through which we test the model solution's robustness against the randomness of surgery duration and the length of stay. Finally, we present a combined optimization–simulation approach that allows us to fine tune the optimization model to trade-off robustness and efficiency. Our study shows that, by planning surgery groups instead of individual cases and by combining optimization and simulation, it is possible to obtain schedules that are both robust and easy to implement. In addition, it shows that such a combined approach allows for the performance of more accurate scenario analyses. The results presented in this paper are based on real data from the Meyer University Children's Hospital in Florence, which is one of the most renowned children's hospitals in Italy. [ABSTRACT FROM PUBLISHER]

This paper describes the application of the combined finite-discrete element method (FDEM) for the simulation of two different rock slides observed at the Alpetto Mine in Cesana Brianza (Italy). Previous numerical modeling conducted to study the stability conditions of the high rock cut are used as comparison for the results obtained. The paper presents how the FDEM simulation was performed and discusses the ability and limits of the currently available combined method to simulate rock slide problems for practical purposes. [ABSTRACT FROM AUTHOR]

Abstract: Sediments of the Marano and Grado Lagoon (Adriatic Sea, Italy) represent one of the world’s most major repositories of mercury (Hg). Its presence is a direct consequence of the historical mining activity in nearby Idrjia (Slovenia), as well as significant discharges from a chlor-alkali plant into the Aussa–Corno river system, which connects to the lagoon. Previous studies have shown that sediment acts as secondary source of Hg species to the overlying water column in natural conditions. However, evidence for the effects of resuspension on the dynamics of Hg species is still lacking. The work reported in this paper formed part of the multidisciplinary “MIRACLE” project, aimed at identifying areas at low risk of Hg bioaccumulation in commercial Manila Clams, an important part of the local economy in this region. The effect of resuspension on the cycling of inorganic mercury (IHg), reactive mercury (RHg) and methylmercury (MeHg) between the sediment and water column was investigated in a mesocosm study. Two experiments were conducted in October 2009 and September 2010 based on material collected from sites heavily impacted by Hg and periodically subjected to dredging activities. Designed to mimic the resuspension of particles, both experiments revealed that the release of Hg species from the solid to the dissolved phase became negligible quickly after the event. MeHg values did not change according to total mercury (THg), suggesting that the enhancement of methylation processes may occur. The findings reported in this paper may be useful for the local management of dredging and fishing activities, although mass balance calculations showed that the total flux of Hg species are trivial compared to lagoon-wide processes. [Copyright &y& Elsevier]

Knowledge of social contact patterns still represents the most critical step for understanding the spread of directly transmitted infections. Data on social contact patterns are, however, expensive to obtain. A major issue is then whether the simulation of synthetic societies might be helpful to reliably reconstruct such data. In this paper, we compute a variety of synthetic age-specific contact matrices through simulation of a simple individual-based model (IBM). The model is informed by Italian Time Use data and routine socio-demographic data (e.g., school and workplace attendance, household structure, etc.). The model is named ''Little Italy'' because each artificial agent is a clone of a real person. In other words, each agent's daily diary is the one observed in a corresponding real individual sampled in the Italian Time Use Survey. We also generated contact matrices from the socio-demographic model underlying the Italian IBM for pandemic prediction. These synthetic matrices are then validated against recently collected Italian serological data for Varicella (VZV) and ParvoVirus (B19). Their performance in fitting sero-profiles are compared with other matrices available for Italy, such as the Polymod matrix. Synthetic matrices show the same qualitative features of the ones estimated from sample surveys: for example, strong assortativeness and the presence of super- and sub-diagonal stripes related to contacts between parents and children. Once validated against serological data, Little Italy matrices fit worse than the Polymod one for VZV, but better than concurrent matrices for B19. This is the first occasion where synthetic contact matrices are systematically compared with real ones, and validated against epidemiological data. The results suggest that simple, carefully designed, synthetic matrices can provide a fruitful complementary approach to questionnaire-based matrices. The paper also supports the idea that, depending on the transmissibility level of the infection, either the number of different contacts, or repeated exposure, may be the key factor for transmission. [ABSTRACT FROM AUTHOR]

Abstract: The safety of railway operations under wind actions has recently become a topical matter due to the development of high-speed trains, which are very sensitive to crosswind conditions. For this reason, RFI (the Italian railway network) has entrusted the University of Genoa with a study of the wind hazard of the Rome–Naples High Speed (HS)/High Capacity (HC) railway line. A consistent part of such a study is focused on the probabilistic analysis of the wind speed and direction along that railway line, with the aim of developing a general procedure that can be applied to any railway line. This paper represents the logical prosecution of a companion paper where numerical simulations have been carried out of the wind fields along the line. These results are used together with a large amount of data measured by neighbouring meteorological stations in order to establish a probabilistic model of the wind speed and direction along the line. Such model provides a full representation of the wind climate and hazard of the railway line, and represents the basic step towards the development of a full risk analysis. Preliminary evaluations are also reported in order to assess the robustness and reliability of the methodology applied and the results obtained. [Copyright &y& Elsevier]

Abstract: The safety of railway operation under wind actions has recently become a topical matter due to the development of high-speed trains, which are very sensitive to crosswind conditions. For this reason, RFI (the Italian railway network) has entrusted the University of Genoa with a study of the wind hazard of the Rome–Naples High Speed (HS)/High Capacity (HC) railway line. A consistent part of this study is focused on the probabilistic analysis of the wind speed and direction along that railway line, with the aim of developing a general procedure that can be applied to any railway line. This paper and its companion illustrate both the general procedure that has been developed and the main results of its application. The present paper specifically deals with the numerical modelling and wind simulations preliminary to the probabilistic assessment of the wind speed along the line, which is treated in the companion paper. [Copyright &y& Elsevier]

Abstract: The use of numerical simulation methods for the Cultural Heritage is of increasing importance for the analysis, conservation, restoration and appreciation of works of art. This is particularly important when their preservation and planned maintenance is the primary aim. Today museums, and particularly historical buildings converted to museums, should be considered as places where precious artefacts should have first-rate protection and conservation. It is a question of solving the compromise between protection, conservation and comfort for works of art and/or visitors, with the consequence that preservation and planned maintenance criteria must prevail over use requirements. Refurbishment and conservation of a building, and requirements for visitor presence and works of art need different thermo-physical indoor parameter values. The present paper concerns the thermal and air velocity analysis of the Salone dei Duecento (the Hall of the Two Hundred of the Palazzo Vecchio (Old Palace)) in Florence. In this paper an appropriate transient 3D model by Computational Fluid Dynamics (CFD) software based on the finite element method (FEM) was used. Variations and interaction between indoor and outdoor microclimatic conditions, and thermo-physical behaviour of the building connected to lighting, visitor presence and cooling–heating fan coils system were considered. The 3D modelling method provided by the present paper can be applied to several situations where there is interaction between outdoor and indoor climate variations and the building structure. It can be very useful for defining measures to preserve tapestries, understanding deterioration processes, and developing new conservation techniques and strategies for care and exhibition. [Copyright &y& Elsevier]

Abstract: The paper presents a methodology that has been developed and implemented for the simulation of electricity use (kWh) as well as electricity pricing (c€/kWh) in buildings. In the simulation, electricity pricing has been treated as dependent on electricity use as energy pricing tariffs usually discriminate between specific electricity consumption zones, time periods, etc. Pricing and electricity use, together, may then provide an estimation of the building electric energy cost (€). The simulation runs on an hourly resolution allowing to highlight some potential wasteful and costly practices in energy use and management and providing insight to user behavior, which has been a key driver for its development. The key aspects of the simulation approach are presented and its use is demonstrated in two different buildings in Greece and Italy. The methodology is now adapted to allow for neural network based, real time training, which will also be briefly introduced. [Copyright &y& Elsevier]

Abstract: The recent crisis in Italian agriculture has forced operators to find new ways of deriving income from their activities. One of the most promising of these is the use of agricultural products and residues as an energy source. In particular, the exploitation of agricultural, industrial and forestry residues and by-products can be a definite advantage in the generation of electrical and thermal energy. This is due to the fact that these materials need to be disposed of and, therefore represent cost, and can be then transformed into an opportunity for revenue. Among the various technologies available for converting biomass into biofuels, thermochemical gasification appears to be the most suitable for the conversion of crop residues (corn and sunflower stalks, rapeseed straw, etc.) as these are characterized by low humidity and a high C/N ratio. On the other hand, the operational problems encountered with current plant architectures, such as the blocking of the biomass flow in the reactor due to low-melting ash content, have limited the use of crop residues in gasification so far. In this paper, a model for the simulation of the biomass thermochemical gasification process is presented. The model is based on a chemical equilibrium hypothesis, i.e. it is assumed that the chemical transformations inside the gasifier can be described by a series of equilibrium reactions independent of each other and, therefore, a precise relationship between products and reactants can be determined. The model is validated by a comparison with data from literature and a sensitivity analysis on process parameters is presented. Finally, the model is applied to the study of the reliability of the gasification of crop residues currently popular in Italy, both in terms of produced gas quality and quantity. [Copyright &y& Elsevier]

SUMMARY In this paper, we investigate ground-motion variability due to different faulting approximations and crustal-model parametrizations in the Messina Straits area (Southern Italy). Considering three 1-D velocity models proposed for this region and a total of 72 different source realizations, we compute broad-band (0-10 Hz) synthetics for Mw 7.0 events using a fault plane geometry recently proposed. We explore source complexity in terms of classic kinematic (constant rise-time and rupture speed) and pseudo-dynamic models (variable rise-time and rupture speed). Heterogeneous slip distributions are generated using a Von Karman autocorrelation function. Rise-time variability is related to slip, whereas rupture speed variations are connected to static stress drop. Boxcar, triangle and modified Yoffe are the adopted source time functions. We find that ground-motion variability associated to differences in crustal models is constant and becomes important at intermediate and long periods. On the other hand, source-induced ground-motion variability is negligible at long periods and strong at intermediate-short periods. Using our source-modelling approach and the three different 1-D structural models, we investigate shaking levels for the 1908 Mw 7.1 Messina earthquake adopting a recently proposed model for fault geometry and final slip. Our simulations suggest that peak levels in Messina and Reggio Calabria must have reached 0.6-0.7 g during this earthquake. [ABSTRACT FROM AUTHOR]

Abstract: The NIO1 (Negative Ion Optimization phase 1) experiment, whose construction has started in 2010 at Consorzio RFX in Padova in collaboration with INFN-LNL, is a radio frequency Hydrogen negative ion source designed to produce a beam current of 130mA with 60keV particle energy. The aim of the experiment is to provide a highly flexible system to test material properties of source components and to benchmark simulation codes for beam optics and plasma behavior. The paper focuses on a conceptual design for NIO1 power supply system on the basis of given operational and performance requirements. The requested ratings fall well within those of products available on the market and the design includes standard commercial solutions for the individual power supplies. The ion source operates at −60kV with respect to ground, leading to a number of design issues at system level and related to mutual connection between power supplies and load, layout and grounding. These aspects, along with the crucial point of ensuring protection to the arc prone beam source, are reviewed and discussed. The study leads to a scheme integrating high voltage power supplies, high current power supplies and a possible solution for passive protection components at the power supply output. [Copyright &y& Elsevier]

Abstract: There is an increasing concern related to the releases of industrial hazardous materials (either toxic or flammable) due to terrorist attacks or accidental events in congested industrial or urban areas. In particular, a reliable estimation of the hazardous cloud footprint as a function of time is required to assist emergency response decision and planning as a primary element of any Decision Support System. Among the various hazardous materials, the hazard due to the road and rail transportation of liquefied petroleum gas (LPG) is well known since large quantities of LPG are commercialized and the rail or road transportation patterns are often close to downtown areas. Since it is well known that the widely-used dispersion models do not account for the effects of any obstacle like buildings, tanks, railcars, or trees, in this paper a CFD model has been applied to simulate the reported consequences of a recent major accident involving an LPG railcar rupture in a congested urban area (Viareggio town, in Italy), showing both the large influence of the obstacles on LPG dispersion as well as the potentials of CFD models to foresee such an influence. [Copyright &y& Elsevier]

Abstract: The European Energy Efficiency Building Directive 2002/91/CE, as well as other acts and funding programs, strongly promotes the adoption of passive strategies for buildings, in order to achieve indoor thermal comfort conditions above all in summer, so reducing or avoiding the use of air conditioning systems. In this paper, the energy performances achievable using an earth-to-air heat exchanger for an air-conditioned building have been evaluated for both winter and summer. By means of dynamic building energy performance simulation codes, the energy requirements of the systems have been analysed for different Italian climates, as a function of the main boundary conditions (such as the typology of soil, tube material, tube length and depth, velocity of the air crossing the tube, ventilation airflow rates, control modes). The earth-to-air heat exchanger has shown the highest efficiency for cold climates both in winter and summer. The possible coupling of this technology with other passive strategies has been also examined. Then, a technical-economic analysis has been carried out: this technology is economically acceptable (simple payback of 5–9 years) only in the cases of easy and cheap moving earth works; moreover, metallic tubes are not suitable. Finally, considering in summer a not fully air-conditioned building, only provided with diurnal ventilation coupled to an earth-to-air heat exchanger plus night-time ventilation, the possible indoor thermal comfort conditions have been evaluated. [Copyright &y& Elsevier]

Abstract: Solid Oxide Fuel Cells (SOFC) are very promising energy conversion devices, producing electricity and heat from a fuel directly via electrochemical reactions. The electrical efficiency of SOFCs is particularly high, so that such systems are very attractive for integration in complex polygeneration systems. In this paper, the integration of SOFC systems with solar thermal collector is investigated seeking to design a novel polygeneration system producing: electricity, space heating and cooling and domestic hot water, for a university building located in Naples (Italy), assumed as case study. The polygeneration system is based on the following main components: concentrating parabolic through solar collectors, a double-stage LiBr–H2O absorption chiller and an ambient pressure SOFC fuel cell. The system also includes a number of additional components required for the balance of plant, such as: storage tanks, heat exchangers, pumps, controllers, cooling tower, etc. The SOFC operates at full load, producing electric energy that is in part self-consumed for powering building lights and equipments, and in part is used for operating the system itself; the electric energy in excess is eventually released to the grid and sold to the public Company that operates the grid itself. The system was designed and then simulated by means of a zero-dimensional transient simulation model, developed using the TRNSYS software; the investigation of the dynamic behavior of the building is also included. The results of the case study were analyzed for different time bases, from both energetic and economic points of view. Finally, a thermoeconomic optimization is also presented aiming at determining the optimal set of system design parameters. The economic results show that the system under investigation may be profitable, provided that it is properly funded. However, the overall energetic and economic results are more encouraging than those claimed for other similar polygeneration systems in the recent literature. [Copyright &y& Elsevier]

The measurement of the physical characteristics of hailstones reaching the ground is usually carried out by means of hailpads, on which the impact of hailstones leaves dents. Hailstone dents provide information about parameters, such as the number N of hailstones, their size M, and their kinetic energy E. In the case of intense hailfalls, however, the dents often overlap and the final measurement may not be totally reliable. This paper presents a computerized simulation with the aim of assessing measurement errors caused by dent overlap. The simulated dents represent several random hailfalls with both exponential size distributions and monodispersed size distributions. The simulated hailpads were measured following the procedure employed in the case of hailpads exposed to authentic hailfalls, and it was thus possible to assess the error due to dent overlap. The results show that dent overlap makes it impossible to measure all the dents, which means that in a real hailfall the number of hailstones registered will often be lower than the number of hailstones that actually hit the ground (up to 25%% may go undetected). Consequently, the energy and mass of the hailstones are also underestimated (they may be up to 50%% higher than the values registered on a hailpad). The maximum size registered, however, does not depend on the degree of overlapping and neither does the slope parameter λλ of the exponential distribution, except when λλ takes higher values. Finally, the authors suggest a heuristic correction of the data obtained by real hailpads based on the results of the simulations. An example is provided that applies these corrections to the 228 hailfalls registered by the Italian hailpad network over a period of 10 yr. The results show that, on average, the correction applied because of overlapping increases the number of hailstones in 3.2%%, the mass in 1.9%%, and the energy in 5.4%%. However, there are cases in which these corrections reached much higher values of up to 6.9%% in N and M, and up to 25.2%% in E. It is therefore advisable to correct dent overlap before carrying out a regional climatic study of hail, since this study would certainly be affected by the errors accumulated by all the hailpads. [ABSTRACT FROM AUTHOR]

Abstract: In this paper the thermal behaviour of a rainscreen ventilated façade has been investigated both experimentally and numerically. Field measurements were performed during the 2009/10 winter season in a test building located in San Mauro Pascoli (Italy) having a squared base of internal dimension of 2.89m and a total internal height of 7.75m. The external walls of this tower are rainscreen ventilated façades with a 24cm air cavity and an external side composed of stoneware with open joints. Ventilation grills are located at the top and at the bottom of the tower. In this work the modelling of the test building using a dynamic thermal simulation program (ESP-r) is presented and the main results discussed. In order to study the rainscreen ventilated façade three different multi-zone models were defined and the comparison with the experimental results has been used in order to select the best ESP-r air flow network for the modelling of this kind of envelope component. The thermal analysis of this envelope component evidenced that the ventilated façade is able to reverse the direction of the heat flux through the envelope in regions characterized by large solar irradiation during the winter and moderate wind velocity, when the indoor–outdoor air temperature difference is small, thereby reducing the energy consumption required for indoor heating. [Copyright &y& Elsevier]

Rockfalls represent a significant geohazards along the SS18 road of Basilicata Region, Italy. The management of these rockfall hazards and the mitigation of the risk require innovative approaches and technologies. This paper discusses a hazard assessment strategy and risk mitigation for rockfalls in a section of SS118, along the coast of Maratea, using LIDAR technique and spatial modelling. Historical rockfall records were used to calibrate the physical characteristics of the rockfall processes. The results of the simulations were used to define the intervention actions and engineering strategy for the mitigation of the phenomena. Within two months, 260 linear meters of high-energy rockfall barriers for impact energies up to 3000 kJ were installed. After that, according to road authority, the SS18 road was opened in a safe condition. The results represent a valid cognitive support to choose the most appropriate technical solution for topography strengthening and an example of good practice for the cooperation between innovative technologies and field emergency management. [ABSTRACT FROM AUTHOR]

Abstract: The energy policy in Europe regarding buildings and the energy efficiency sector are regulated by two directives: 2002/91/CE – EPBD and 2006/32/CE – EEESD . The CEN has elaborated a standard to revise all European normatives about building energy performance and HVAC plants. The “CEN Umbrella” CEN/TR 15615 includes a new version of EN ISO 13790:2008 and a new standard about heating plant, use and contributions of renewable energy sources. Furthermore, the CEN Standard provides a software version for technicians. In this paper we present a Round Robin Test between a selection of softwares applied to an Italian case study. The selected calculation methodologies, range from research packages to extra-simplified software. Furthermore, the Italian procedure described in UNI TS 11300 has been analyzed and considered as the reference for all other calculation methodologies. The results of the Round Robin Test show the relationship between thoroughness of data input and energy evaluation accurancy. The more the input data is affected by uncertainty, the less precise is the energy efficiency calculation. On the other hand the energy performance of building evaluation accurancy depends on the aim of the simulation: the energy audit, the energy design or the energy labeling (certification). [ABSTRACT FROM AUTHOR]

Abstract: The paper addresses the issues of modelling and managing Intermodal Transportation Systems (ITS) at the operational level, considering the impact of the new Information and Communication Technologies (ICT). ITS are regarded as discrete event systems and are modelled in a timed Petri net framework. In order to show the efficiency of the ITS modelling and controlling technique, the case study of the ferry terminal of Trieste (Italy) is considered. The results show that the approach can be employed to verify the potential of ICT for efficient real time management of ITS, and their impact on the ITS infrastructures. [Copyright &y& Elsevier]

Abstract: This paper describes the results of a rockfall hazard assessment for the village of San Quirico (Abruzzo region, Italy) based on an engineering-geological model. After the collection of geological, geomechanical, and geomorphological data, the rockfall hazard assessment was performed based on two separate approaches: i) simulation of detachment of rock blocks and their downhill movement using a GIS; and ii) application of geostatistical techniques to the analysis of georeferenced observations of previously fallen blocks, in order to assess the probability of arrival of blocks due to potential future collapses. The results show that the trajectographic analysis is significantly influenced by the input parameters, with particular reference to the coefficients of restitution values. In order to solve this problem, the model was calibrated based on repeated field observations. The geostatistical approach is useful because it gives the best estimation of point-source phenomena such as rockfalls; however, the sensitivity of results to basic assumptions, e.g. assessment of variograms and choice of a threshold value, may be problematic. Consequently, interpolations derived from different variograms have been used and compared among them; hence, those showing the lowest errors were adopted. The data sets which were statistically analysed are relevant to both kinetic energy and surveyed rock blocks in the accumulation area. The obtained maps highlight areas susceptible to rock block arrivals, and show that the area accommodating the new settlement of S. Quirico Village has the highest level of hazard according to both probabilistic and deterministic methods. [Copyright &y& Elsevier]

Abstract: The paper investigates the energetic and economic feasibility of a solar-assisted heating and cooling system (SHC) for different types of school buildings and Italian climates. The SHC system under investigation is based on the coupling of evacuated solar collectors with a single-stage LiBr–H2O absorption chiller; auxiliary energy for both heating and cooling is supplied by an electric-driven reversible heat pump. The SHC system was coupled with different types of school buildings located in three different Italian climatic zones. The analysis is carried out by means of a zero-dimensional transient simulation model, developed using the TRNSYS software; the analysis of the dynamic behaviour of the building was also included. An economic model is proposed, in order to assess the operating and capital costs of the systems under analysis. Furthermore, a parametric analysis and a subsequent mixed heuristic-deterministic optimization algorithm was implemented, in order to determine the set of the synthesis/design variables that maximize system profitability. The results are encouraging, as for the potential of energy saving. On the contrary, the SHC economic profitability can be achieved only in case of public funding policies (e.g. feed-in tariffs), as always happens for the great majority of renewable energy systems. [Copyright &y& Elsevier]

The paper introduces a simulation/optimization procedure for the assessment and the selection of infrastructure alternatives in a complex water resources system, i.e. in a multisource (reservoirs) multipurpose bulk water supply scheme. An infrastucture alternative is here a vector X of n decision variables describing the candidate expansions/new plants/water transfers etc. Each parameter may take on a discrete number of values, with its own investment cost attached. The procedure uses genetic algorithms for the search of the optimal vector X through operators mimicking the mechanisms of natural selection. For each X, the value of the objective function (O.F.) is assessed via a simulation model. Simulation is necessary as the O.F. contains, besides investment costs, also incremental operation costs and benefits that depend on the incremental water amounts which the alternative can provide. The simulation model transforms a thirty-year hydrologic input at daily/monthly scale in water allocations, accounting for the usual nonnegativity constraints and using some simple, sytem-specific rules aimed at reducing spills and at sharing water deficits among demand centres. Different O.Fs and constraints have been tested, such as incremental financial cost/benefit minimization under various maximum water deficit constraints scenarios or cost/benefit mimization including scarcity costs. This latter approach has the advantage of implicitly allowing for the magnitude of deficits, but requires the assessment of deficit-scarcity cost relationships. The application of the procedure to a water resources system in south-western Sicily shows that the model is able to converge to results that are consistent with the planning options expressed by the selected O.Fs. [ABSTRACT FROM AUTHOR]

Abstract: Complex decision-making problems, related to planning and management of irrigation water resources, generally preclude the use of large, distributed-parameter models, which are then commonly substituted by lumped-parameter models. This paper, with the aim of improving the quality of these latter, introduces a new approach for their design. This approach is based on metamodelling, which proposes to identify a simple, lumped-parameter model on the basis of the data produced via simulation with a distributed-parameter model. The approach proposed is tested on a real-world case study, namely the identification of a metamodel describing the water demand of the Muzza–Bassa Lodigiana irrigation district (Italy). The metamodel, which inherits the physical description of the original distributed-parameter model, is sufficiently simple to permit the resolution of an optimal control problem, i.e. the design, via stochastic dynamic programming, of the release policy of Lake Como, serving the Muzza irrigation district. [Copyright &y& Elsevier]

For at least a century academics and governmental researchers have been developing measures that would aid them in understanding income distributions, their differences with respect to geographic regions, and changes over time periods. It is a fascinating area due to a number of reasons, one of them being the fact that different measures, or indices, are needed to reveal different features of income distributions. Keeping also inmind that the notions of poor and rich are relative to each other, Zenga (2007) proposed a new index of economic inequality. The index is remarkably insightful and useful, but deriving statistical inferential results has been a challenge. For example, unlike many other indices, Zenga's new index does not fall into the classes of L-, U-, and V - statistics. In this paper we derive desired statistical inferential results, explore their performance in a simulation study, and then use the results to analyze data from the Bank of Italy Survey on Household Income and Wealth (SHIW). [ABSTRACT FROM AUTHOR]

Abstract: The activity of Stromboli volcano is characterized by very low energy explosions, occurring every 10–15 min, throwing out lava above the crater rim. During 2007, the volcano showed an anomalous activity in which new effusive vents developed (27 February and 9 March) and a major explosion took place on 15 March. This paper presents an integrated study based on a structural geological field survey, interferometric radar monitoring and numerical modelling on the deformations of the upper NW flank of the volcano (Sciara del Fuoco — SdF). The field survey carried out during the 2007 events shows the development of mainly NE-striking fissures and fractures on the northern part of the upper SdF. In January 2007, the ground-based synthetic aperture radar (GB-InSAR), installed on the flank of the SdF, showed a progressive acceleration of movement on the NE crater preceding the eruption of 27 February 2007. By the first half of February, the acceleration also involved the upper portion of the SdF and on 27 February the eruption started with the opening of new vents and deformation rates higher than the measurement capability of the radar device. On 8–9 March 2007, the GB-InSAR highlighted the formation of a bulge on the NW sector of the SdF, preceding the opening of an additional vent. To understand the deformation pattern recorded during the eruption, a numerical simulation was carried out by using the FLAC 3D code. Based on the integration of all the data, the deformations observed in the pre-effusive phase (before 27 February) seem to be related to the intrusion of a SW–NE striking dyke. The bulging recorded before the 9 March vent opening is instead to be associated with the intrusion of a sub-horizontal sill. [Copyright &y& Elsevier]

Abstract: The paper discusses a model of robot perception based on a comparison loop process between the actual and the expected robot input sensory data generated by a 3D robot/environment simulator. The perception loop process is operating in CiceRobot, a functional robot architecture implemented on an autonomous robot RWI B21 offering guided tours at the Archaeological Museum of Agrigento, Italy. [Copyright &y& Elsevier]

Summary: The main objective of this paper is to evaluate a threshold-based flash flood warning method, by considering a wide range of climatic and physiographic conditions, and by focusing on ungauged basins. The method is derived from the flash flood guidance (FFG, hereafter) approach. The FFG is the depth of rain of a given duration, taken as uniform in space and time on a certain basin, necessary to cause minor flooding at the outlet of the considered basin. This rainfall depth, which is computed based on a hydrological model, is compared to either real-time-observed or forecasted rainfall of the same duration and on the same basin. If the nowcasted or forecasted rainfall depth is greater than the FFG, then flooding in the basin is considered likely. The study provides an assessment of this technique based on operational quality data from 11 mountainous basins (six nested included in five larger parent basins) located in north-eastern Italy and central France. The model used in this study is a semi-distributed conceptual rainfall–runoff model, following the structure of the PDM (probability distributed moisture) model. Two general questions are addressed: (1) How does the efficiency of the method evolve when the simulation parameters can not be calibrated but must be transposed from parent gauged basins to ungauged basins? (2) How sensitive are the results to the method used to estimate the initial soil moisture status? System performances are evaluated by means of categorical statistics, such as the critical success index (CSI). Results show that overall CSI is equal to 0.43 for the parent basins, where the hydrological model has been calibrated. CSI reduces to 0.28 for the interior basins, when model parameters are transposed from parent basins, and to 0.21, when both model parameters and soil moisture status is transposed from parent basins. Performance differences between FFG and use of time-constant soil moisture status are very high for the parent basins and decrease with decreasing the system accuracy. The percent difference amounts to 53% for the parent basins, to 25% for interior basins with parameter transposition, and to 19% for interior basins with parameter and soil moisture status transposition. These results improve our understanding of the applicability and reliability of this method at various scales and under various scenarios of data availability. [Copyright &y& Elsevier]

Abstract: In the frame of the activities related to ITER divertor R&D, ENEA CR Brasimone was in charge by EFDA (European Fusion Development Agreement) to investigate the thermal-hydraulic behaviour of the full-scale divertor plasma facing components, i.e. the outer vertical target, the inner vertical target and the dome-liner, both in steady state and during draining and drying transient. The investigation was performed by means of both experimental test campaigns performed at ENEA CR Brasimone and theoretical simulation developed in RELAP5 Mod.3.3 environment at the Department of Nuclear Engineering of the University of Palermo (DIN). This paper presents the achieved experimental results for both steady state and transient tests. Moreover, the level of the implementation of the predictive hydraulic model, based on RELAP5 code, as well as its results are described, discussed and compared with the experimental ones. [Copyright &y& Elsevier]

High frequency dissolved oxygen measurements in Mediterranean coastal lagoons show different dynamics on different time scales. In this paper the seasonal and daily dynamics are analysed and discussed and a continuous simulation model is developed to represent them for the salt lake of Fogliano (Italy). Field and laboratory experiments evidenced that primary production slows down in highly oxygenated and irradiated summer days, acting in feedback regime with the oxygen already present in the media, that wind stress contributes in exceeding the oxygen saturation concentration and that there is a firm correlation between oxygen consumption at the sediment layer and overhanging water temperature. Water temperature, solar radiation and wind regime are the forcing functions of the model; the main state variables are dissolved oxygen and detritus in the pelagic and benthic layers, together with carbon dioxide and vegetal biomass. The slow seasonal and fast diel dynamics are both revealed by the model evidencing detailed aspects of oxygen dynamics in a coherent agreement with field observed data trends. [Copyright &y& Elsevier]

The analysis of socio-ecological systems requires new, qualitatively distinct, evaluation schemes and appropriate investigation tools that enable an integrated assessment of ecological, social, and economic factors since human land use is a major force driving landscape change, landscape dynamics can be better understood in the context of complex social-ecological systems (SESs). Tourist resorts are deemed as socio-ecological systems, and tourism is a tool for development but could affect the quality of ecosystem goods and services since it could degrade natural renewable and non-renewable resources. In this paper we develop a minimal descriptive model of socio-ecological systems based on tourism, starting from the work of Casagrandi and Rinaldi [Casagrandi, R., Rinaldi, S., 2002. A theoretical approach to tourism sustainability. Conserv. Ecol. 6 (1), 13 (Online). URL: http://www.consecol.org/vol6/iss1/art33], and based on data from a real tourist destination in southern Italy. We develop the model focusing on the interplay among tourists (T), quality of ecosystem goods and services (E), and capital (C), intended as accommodation and entertainment facilities, to make the model more realistic, and to provide a tool for scenario building to support more effectively sustainable management of tourist destination. In particular, we focus on the interplay between tourism and ecosystem quality, distinguishing two main tourist typologies – mass and eco-tourists – and taking into account ecosystem quality in terms of ecosystem goods and services, with a time dependent function, and defining a degradation coefficient of tourist site to be used as a bifurcation parameter. We explore different scenarios, with regards to coexistence of tourist classes and equilibria stability, as generated by variation of the bifurcation parameter. Finally, we discuss the overall results in terms of basins of attraction and stability landscape, and system resilience together with their implications for sustainable tourist destination management. [Copyright &y& Elsevier]

— The study of surface deformation due to seismic activity is often made using dislocations with uniform slip and simple geometries. A better modeling of coseismic and postseismic surface displacements can be obtained by using dislocations with variable slip and nonregular shapes. This is consistent with the asperity model of fault surfaces, assuming a friction distribution on faults made of locked zones with much higher friction than surrounding zones. In this paper we consider the 1997–1998 Colfiorito seismic sequence. The coseismic surface displacements in the Colfiorito zone are used in order to infer the slip distribution on the fault surface at different stages of the sequence. The displacement field has been modeled varying the slip distribution on the fault, and comparing the deformation observed by SAR and GPS techniques with model results. The slip distribution is calculated by Monte Carlo simulations on a normal fault with the dip angle equal to 40°. A good approximation is obtained by using square asperity units of 1.5×1.5 km2. In the first stage, we employed a simplified model with uniform slip, in which each asperity unit is allowed to slip a constant amount or not to slip at all, and in the second stage, we evaluate the slip distribution in the dislocation area determined by the Monte Carlo inversion: in this case we allow unit cells to undergo different values of slip in order to refine the initial dislocation model. The results show that the 1997 seismic events of the sequence can be modeled by irregular dislocations, obtaining a good fit to the DInSAR and GPS observations. The model also confirms the results of previous studies by a different methodology, defining the distribution of asperities on the fault plane using the fault geometry, the geodetic data and the seismic moment of the 1997–1998 Colfiorito seismic sequence. Furthermore, the analysis of 1997 aftershocks in the seismogenic region shows a strong correlation between most events and the asperity distribution, which can be considered as an independent test of the validity of the model. [ABSTRACT FROM AUTHOR]

The paper presents a comparison between the performances of two full scale wastewater treatment plants operating in Italy, considering the mass balances including P treatments, and results coming from an analysis of 16 similar plants in Europe and USA, in order to evaluate sludge overproduction due to chemical P removal adoption. Specific production of 9.5 and 12.5 kgTS/P.E.y were found for a BNR and denitrification plant scheme respectively. These results were compared, on a mass balance basis, with the performances coming from the adoption of the integrated waste/wastewater cycles, in which OFMSW fermentation is used as C source to promote BNR performances and P removal from anaerobic supernatants as struvite crystals. ASM2 simulations are used to verify the advantages coming from this approach in terms of sludge reduction. A complete mass balance of the process is carried out, and it is shown that this last process allows us to achieve the lowest sludge production among the processes considered, coupling this with the economic benefits coming from OFMSW disposal and struvite crystallisation. [ABSTRACT FROM AUTHOR]

This paper presents a new tool for failure mode and effect analysis developed for a new Integrated Gasification and Combined Cycle plant in an important Italian oil refinery. The methodology is based on the integration between a modified Failure Mode Effect and Criticality Analysis (FMECA) and a Monte Carlo simulation as a method for testing the weights assigned to the measure of the risk priority numbers (RPNs). The RPN proposed consists of a weighted sum of six parameters (safety, machine importance for the process, maintenance costs, failure frequency, downtime length, and operating conditions) multiplied by a seventh factor (the machine access difficulty). Adopting this tool and considering the budget constraints, the best maintenance policy has been selected for each plant facility (about 140 in total). Copyright © 2000 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Hazelnut is an emerging tree crop in the global market and current production levels are unable to sustain the demand for fruits. Research efforts are needed to support private and public stakeholders with knowledge that can help improving the management of the agricultural systems, by enhancing yield levels and safeguarding environmental sustainability. This paper extends the application of a process-based hazelnut simulation model from the single orchard where it was initially calibrated to four orchards located in Italy, Chile and Georgia, using three-year experimental datasets (2015–2017). The model sensitivity to parameter changes was assessed twice (screening and quantitative analysis) to identify the most relevant parameters affecting the prediction of leaf area index, fruit yield and soil moisture. These parameters were automatically calibrated to maximize the model accuracy in predicting field data, by comparing model performances with original parameterization. According to current model structure, canopy expansion and plant dimensions accounted for most of the variability in leaf area index simulation. Photosynthesis and root water uptake played a prominent role in affecting the model predictions of yield and soil moisture, respectively. The automatic calibration increased the accuracy in predicting leaf area index (average RRMSE = 19.3%), fruit yield (average RRMSE = 16.3%) and soil moisture (average RRMSE = 12.5%). This study provides quantitative information to support calibration activities and insights for collection of new experimental data in the short-term, while laying the groundwork for the use of the model for yield forecasting activities as the medium goal. • A hazelnut simulation model is applied on four orchards in Chile, Italy and Georgia. • The sensitivity analysis identifies the key parameters affecting model accuracy. • The model is calibrated with experimental data to maximize its accuracy. • The methodological workflow is reusable for further operational use of the model. [ABSTRACT FROM AUTHOR]