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• We investigated we can save optimizing delivery time and intensity of a street light. • Pre-defined regulation save a power consumption of 38%. • Traffic adaptive regulation save a power consumption of 60%. The aim of this work is to simulate and compare the energy savings potentially applicable to the consumption data of the Smart Street pilot system located at the ENEA Casaccia R.C. (Rome). The astronomical lighting system energy consumption (baseline) is compared to the simulation of a pre-defined regulation: it allows the lights dimming (and therefore a reduction of consumptions) based on a statistics averages of the traffic flow rate, differentiated according to the day of the week. Then the baseline consumption is compared to the simulation of an adaptive configuration based on the traffic flow rate. [ABSTRACT FROM AUTHOR]

This paper focuses on the development of a new logistic approach based on reliability and maintenance assessment, with the final aim of establishing a more efficient interval for the maintenance activities for Unmanned Aerial Vehicles (UAV). In the first part, we develop an architectural philosophy to obtain a more detailed reliability evaluation; then, we study the intrinsic reliability at the design stage in order to avoid severe critical issues in the UAV. In the second part, we compare different maintenance philosophies for UAVs and develop the concepts of preventive and corrective maintenance that consider the system subjected (until real “hard failure”) to partial performance degradation (“soft failure”). Finally, by evaluation of the uncertainty through the confidence interval, we determine the new soft failure limits, taking into account the general knowledge of the systems and subsystems in order to guarantee the proper preventive maintenance interval. [ABSTRACT FROM AUTHOR]

Abstract: The possible influence on the Castel Porziano Presidential Estate pine forest (Italy) of pollutant-rich air masses from the neighboring metropolitan area of Rome is analyzed. This study aims to highlight the consequences which this natural reserve located along the coast may suffer due to the vicinity of the metropolitan area. Two case studies, one representative of synoptic and the other of breeze patterns, are presented and analyzed to evaluate how the local wind circulation can influence these processes of mutual interaction between the wooded and the urban area nearby. This is a common situation in many other places around the world. To this end an up-to-date version of a method for gas profile retrieval in the lower troposphere, developed by the authors, is exploited to study the time evolution of the vertical structure of O3 and NO2 concentrations on the Estate. The method consists of applying an inversion technique, based on the weighted Chahine algorithm, to DOAS (Differential Optical Absorption Spectroscopy) remote-sensing measurements. The analysis of the retrieved vertical profiles shows that the degradation process associated with the arrival of air masses rich in photo-chemical pollutants, due to breeze circulation modified by the Coriolis Effect, is more apparent at upper levels than near the surface, affecting to a greater degree the higher branches of the trees. The paper also examines the impact of O3 on the wooded part of the Castel Porziano Estate. The incidence of this effect is evaluated with the analysis of the so-called AOT40 parameter. [Copyright &y& Elsevier]

This paper presents an evaluation of the nitrogen dioxide (NO2) trend inferred from UV-visible zenith-sky measurements performed at the 'Ottavio Vittori' ground-based research station (http://www.isac.cnr.it/cimone) at Monte Cimone (44.18° N, 10.7° E, 2165 m above sea level (a.s.l.)). Experimental data series are obtained from the measured spectra adopting a retrieval procedure according to differential optical absorption spectroscopy (DOAS) methodology. Data series cover the period from 1993 to 2009, with limited interruptions due to technical maintenance of the instrument or poor meteorological conditions. The NO2 trends are calculated with a linear regression model considering different factors assumed to contribute to NO2 atmospheric content. Before running the model, a procedure for data quality control was applied to reduce or exclude the influence of measurements affected by poor meteorological conditions or the vertical transport of polluted air masses from the lower troposphere. The negative trends obtained for sunrise (a.m.) and sunset (p.m.) NO2 measurements are in good agreement with previous studies accomplished for ground-based stations in the northern hemisphere. [ABSTRACT FROM AUTHOR]

This paper presents a methodology for the retrieval of the vertical profile of atmospheric gas pollutants in the boundary layer from ground-based remote sensing measurements. Nitrogen dioxide (NO2) and ozone (O3) slant column amounts were obtained with the differential optical absorption spectroscopy (DOAS) technique used in the multiple-axis configuration (referred to as multiaxis DOAS). The measurements were carried out in the Presidential Estate at Castel Porziano (near Rome) from September to November 2006, within a program started in 1994 for studying and monitoring the Estate's environment. The retrieval of information on trace gas vertical profiles from the slant column amounts requires as follows: 1) the simulation of the radiative transfer in the atmosphere for air mass factor calculation and 2) the application of inversion schemes. This paper illustrates and discusses the vertical profiles of NO2 and O3 obtained from multiaxis DOAS measurements and their daily evolution on October 29, 2006. [ABSTRACT FROM AUTHOR]

Abstract: A correct interpretation of diffuse solar radiation measurements made by Differential Optical Absorption Spectroscopy (DOAS) remote sensors require the use of radiative transfer models of the atmosphere. The simplest models consider radiation scattering in the atmosphere as a single scattering process. More realistic atmospheric models are those which consider multiple scattering and their application is useful and essential for the analysis of zenith and off-axis measurements regarding the lowest layers of the atmosphere, such as the boundary layer. These are characterized by the highest values of air density and quantities of particles and aerosols acting as scattering nuclei. A new atmospheric model, PROcessing of Multi-Scattered Atmospheric Radiation (PROMSAR), which includes multiple Rayleigh and Mie scattering, has recently been developed at ISAC-CNR. It is based on a backward Monte Carlo technique which is very suitable for studying the various interactions taking place in a complex and non-homogeneous system like the terrestrial atmosphere. PROMSAR code calculates the mean path of the radiation within each layer in which the atmosphere is sub-divided taking into account the large variety of processes that solar radiation undergoes during propagation through the atmosphere. This quantity is then employed to work out the Air Mass Factor (AMF) of several trace gases, to simulate in zenith and off-axis configurations their slant column amounts and to calculate the weighting functions from which informations about the gas vertical distribution is obtained using inversion methods. Results from the model, simulations and comparisons with actual slant column measurements are presented and discussed. [Copyright &y& Elsevier]

An UVVis spectrometer was installed at Mt. Cimone Station in 1993. Since then it carried out zenith scattered solar radiation measurements at sunrise and sunset in the 407–464 nm spectral region. Data has been processed through DOAS methodology in order to obtain NO2 slant column. An inversion algorithm is used to calculate the gas vertical distribution from ground based column amount measurements so that the gas content in stratosphere and troposphere is evidenced. Two years data (1995–1996) are shown and discussed. [Copyright &y& Elsevier]

The paper shows the steps for the preliminary studies of an AUV for shallow water: the first part illustrates the vehicle architecture and the philosophy that permeates the various design choices. In the second part illustrates an innovative method for increasing longitudinal stability based on Takagi-Sugeno (T-S) Fuzzy Inference System: it saves a lot of computational time and, by simplifying the calculation, it is also suitable for remarkably simple computers such as Arduino. in the third part is simulated the behavior of the AUV: thanks to the data taken from the previous hydrodynamic simulation, we can establish the behavior of its longitudinal stability and the computational savings due to the T-S method. [ABSTRACT FROM AUTHOR]

The paper shows the simulation of the behavior of a swarm of underwater drones (AUV) diffused in a closed section of the sea and inserted from a single starting point: Based on a few essential rules, we will see how their behavior evolves and how they manage to spread throughout the area assigned to them. In the first part of this work, after defining the design of the vehicle, we introduce our vision of the swarm, its problems, and its strengths. Later, we show how to spread a series of underwater drones with "diffused intelligence" (swarm) and its microscopic diffusion model. In the last part, we present the simulation that supports our approach to the swarm. [ABSTRACT FROM AUTHOR]

This paper is a section of several preliminary studies of the Underwater Drones Group of the Università degli Studi "Roma Tre" Science Department: We describe the study philosophy, the theoretical technological considerations for sizing and the development of a technological demonstrator of a high accuracy buoyancy and depth control. We develop the main requirements and the boundary conditions that design the buoyancy system and develop the mathematical conditions that define the main parameters. [ABSTRACT FROM AUTHOR]

The automatic identification system (AIS) facilitates the monitoring of ship movements and provides essential input parameters for traffic safety. Previous studies have employed AIS data to detect behavioral anomalies and classify vessel types using supervised and unsupervised algorithms, including deep learning techniques. The approach proposed in this work focuses on the recognition of vessel types through the "Take One Class at a Time" (TOCAT) classification strategy. This approach pivots on a collection of adaptive models rather than a single intricate algorithm. Using radar data, these models are trained by taking into account aspects such as identifiers, position, velocity, and heading. However, it purposefully excludes positional data to counteract the inconsistencies stemming from route variations and irregular sampling frequencies. Using the given data, we achieved a mean accuracy of 83% on a 6-class classification task. [ABSTRACT FROM AUTHOR]

This work presents measurements obtained with the multi‐input spectroradiometer GASCOD/A4π, the Fourier transform far‐infrared interferometer SAFIRE‐A and the two‐channel chromatograph HAGAR, on board the M‐55 Geophysica stratospheric aircraft during the APE–GAIA campaign, held in September–October 1999 over the Antarctic Peninsula. The paper aims to investigate the gas mixing ratio distributions at the flight altitude, during a recovery phase of the reservoir species in the lower stratosphere in the Antarctic spring. Attention is focused on the daytime flight of 23 September, when the aircraft flew inside the vortex at two different altitudes (about 16.5  km and 18.5  km). Concentration distributions were examined for NO 2 , N 2 O, O 3 , BrO, ClO, HCl, H 2 O and HNO 3 , during flight inside and outside the vortex. The NO 2 maxima were well defined in the edge region both on entry into and exit from the vortex at different flight altitudes. Simultaneous concentration measurements of HNO 3 and H 2 O showed a denitrification but not dehydration inside the vortex core. The reformation of chlorine reservoirs is investigated. It was evident that the re‐conversion of HCl was favoured in the Cl+CH 4 branches, and its high mixing ratio up to 1  ppbv at 425K surface confirms that low ozone air masses inside the vortex and strong sunlight greatly favour a more rapid formation of passive chlorine reservoirs. [ABSTRACT FROM AUTHOR]

A geometrical method to determine the vertical distribution of a trace gas in the lower troposphere is presented. The technique is based on quasi-simultaneous measurements of diffuse solar radiation with spectrometric equipment observing the atmosphere from different viewing directions and a measurement of a distant lamp. Differential optical absorption spectroscopy (DOAS) algorithms are applied to retrieve the slant column densities (SCDs) of the analyzed compound. A recursive procedure involving the set of observed SCDs, the geometry of measurement, and several offline radiative transfer simulations provides the vertical profile of the target trace gas. This technique is applied to nitrogen dioxide (NO2) SCDs, and the results are compared to the output of the modeling system Gas Aerosol Modeling Evaluation System (GAMES). The correlation coefficient between the DOAS and GAMES NO2 concentration profiles is 0.7 and shows a nonnegligible variability as a function of altitude and sky conditions. [ABSTRACT FROM PUBLISHER]

Abstract: The environmental impact of large vessel exhaust gases on port and coastal areas is a subject of great interest due both to increasing maritime traffic and the vicinity to highly populated urban zones. In lagoon cities the pollution from maritime traffic is greater than in other coastal areas. Therefore monitoring and evaluation of pollutants produced by ships navigating through the principal transport channels become necessary. In the case of Venice, the Giudecca Channel, crossing the city centre, is used both by urban maritime traffic and by large vessels docking in the port. In this work, the FRE–DOAS (Flow Rate Emission with Differential Optical Absorption Spectroscopy) methodology developed to evaluate gaseous pollutant flow rates from moving sources is presented. This methodology is applied to a set of spectral measurements performed with a Multi axis DOAS remote sensing system, allowing a determination of vessel emissions and evaluation of their impact on pollution in Venice. Two one-month measurement campaigns were carried out: from June 12 2007 to July 12 2007 and from September 12 2007 to October 12 2007. The individual flow rates released by large and medium-sized vessels and the total flow rate emissions due to the total traffic along the Giudecca Channel for every day with appropriate meteo conditions during the campaigns are estimated. The average daily mass of gas emitted by large and medium-sized ships during their passage through the Channel was evaluated as about 205 kg for SO2 and 284 kg for NO2. These values make up only about 30% of total daily traffic emission. These results are extremely interesting, because they demonstrate inequivocably the effectiveness of the proposed system for remote measurements, opening a new frontier in maritime traffic emission control in harbour areas or in those coastal zones subject to heavy maritime traffic. Moreover, the low values obtained for some large modern cruise ships indicate the use of Low Sulphur Fuels, even though these are not yet required by local regulations. [Copyright &y& Elsevier]

Abstract: Areas with dimensions of 1000–3000km in which the total ozone content (TOC) decreases fast are called ozone mini-holes. They are generated mainly dynamically in two ways, either by poor-ozone air mass transport from the tropics to higher latitudes by planetary wave activity or, they are connected with strong adiabatic uplifting of the tropopause height. An ozone mini-hole, generated by the second mechanism, was observed over the Balkan Peninsula on 19/21 March 2005. In the middle of March, the polar vortex was strongly disturbed by Rossby waves, reaching up to the lower stratosphere. Warming episodes over a geographical area, covering the Barents Sea and the Polar Sea north from Central Siberia, displaced a polar vortex fragment extremely southwards. However, the vorticity was weak and the stratospheric temperatures did not reach low values, providing conditions for ozone chemical destruction via heterogenic reactions. At the same time, a Rossby wave ridge was located below the European polar fragment. In the period from 13 to 19 March, the thermal tropopause over Sofia was uplifted almost by 3km. Ozone distributions observed by the SCIAMACHY instrument on 18–21 March show a fast TOC decrease westwards from Ireland, which was moving eastwards during the next days, increasing the area in which the ozone content decreased. On 20/21 March low ozone content was observed above the Stara Zagora (42°N, 25°E) ground-based station by means of the GASCOD instrument, using DOAS technique. The TOMS Earth probe instrument detected 237DU over Sofia. This is a record low March value from the beginning of the TOMS instrument measurements in 1978. In March/April the ozone distribution was characterized by its mean annual maximum of 360DU at 42°N. Using the TUV model, the UV-index was calculated for regions of 2000m height, typical for the mountains southwards of Sofia. The UV-index was very high (almost 10). This is a result not only of the low TOC but also of the relatively high zenith angle at middle latitudes in March. [Copyright &y& Elsevier]

Abstract: Studies have shown that the total ozone amount and the ozone mixing ratio on the Earth’s equator correlate with the 27-day rotational modulation of the solar activity.We report some first results of our research, concerning possible links between the short-term solar activity, i.e., variations on the rotational time-scale, and the stratospheric NO2. The solar activity variations and the atmospheric responses were studied by means of wavelet analysis, cross-correlation and cross-wavelet analysis. It is found out that the 27-day solar cycle in the UV irradiation is modulated by a longer period of several months; this longer period is probably related with active region growth and decay (ARGD). That kind of modulation produces shortening or extension of the 27-day basic period, ranging from 22 to 34 days. The modulation is a consequence of ARGD and hence, results from a variable pattern of spots and active regions on the solar surface. We find a similar time-frequency behaviour in the wavelet maps of NO2 slant column amounts, derived from DOAS measurements at the Stara Zagora station as well as in the total ozone amount, obtained by the GOME instrument during solar cycle 23. For those time intervals when the cross-correlation between the variation of the short-term solar activity and that of the trace gas species is positive, the cross-correlation coefficients are up to 0.6 for the NO2 and up to 0.5 for the ozone variation. [Copyright &y& Elsevier]

Several UV–visible spectrometers have been developed at the ISAC‐CNR Institute. Differential Optical Absorption Spectroscopy (DOAS) methodology is applied to their measurements to monitor the amounts of stratospheric trace gases: mainly ozone (O 3 ) and nitrogen dioxide (NO 2 ) which is involved in the ozone cycle. Observations of the scattered zenith‐sky light were performed with one of these instruments installed at the Terra Nova Bay station (TNB), Antarctica. GASCOD (Gas Analyzer Spectrometer Correlating Optical Differences) is described briefly and a method for data analysis and validation of the results introduced. Some aspects of the DOAS technique are presented: the algorithm allowing the best spectral alignment between spectra obtained with GASCOD and a high‐resolution wavelength calibrated spectrum, is explained. Simple considerations allow for calculation of the NO 2 concentration in the background spectrum used in DOAS analysis. For the period of activity of the GASCOD at TNB (1996–2003), the results of NO 2 vertical column density (VCD) at twilight show a maximum in the summer and a minimum in the winter. Three years of measurements (2001–2003) are analysed in terms of stratospheric temperature and potential vorticity to obtain information about stratospheric warming that occurred in 2002 over Antarctica. The correlation between NO 2 atmospheric content and stratospheric temperature is highlighted. The diurnal variations of NO 2 , which are controlled by photochemistry, show an unusual behaviour at high latitudes. Analysis of the a.m./p.m. ratios—the sunrise NO 2 VC (a.m.) over the sunset VC (p.m.)—during different seasons and at various Solar Zenith Angles (SZA) is presented and discussed. [ABSTRACT FROM AUTHOR]

Nitrogen dioxide (NO2) is a representative of a family of chemically very active radicals NOx=NO+NO2. These radicals catalytically destroy the ozone and play a significant role in other ozone-destroying catalytic cycles. In the polar night NO2 can deactivate ClO by a termolecular reaction to form the reservoir gas Cl0NO2. In this way NO2 restricts the ozone destruction in the polar vortex. NO2 also takes part in heterogeneous reactions, which occur on the surface of polar stratospheric clouds.For the trace gases study and particularly for the nitrogen dioxide a spectrometric instrument GASCOD-BG was installed at the Solar Terrestrial Influences Laboratory - Bulgarian Academy of Sciences , Stara Zagora Department in August 1999. The instrument was developed at the Institute of Atmospheric and Oceanic Sciences at the Council of National Research, Italy, Bologna. The results of the NO2 observation for more than two years are presented in this paper. [Copyright &y& Elsevier]