25 research outputs found
Traffic Signal Control with Communicative Deep Reinforcement Learning Agents: a Case Study
In this work we theoretically and experimentally analyze Multi-Agent
Advantage Actor-Critic (MA2C) and Independent Advantage Actor-Critic (IA2C),
two recently proposed multi-agent reinforcement learning methods that can be
applied to control traffic signals in urban areas. The two methods differ in
their use of a reward calculated locally or globally and in the management of
agents' communication. We analyze the methods theoretically with the framework
provided by non-Markov decision processes, which provides useful insights in
the analysis of the algorithms. Moreover, we analyze the efficacy and the
robustness of the methods experimentally by testing them in two traffic areas
in the Bologna (Italy) area, simulated by SUMO, a software tool. The
experimental results indicate that MA2C achieves the best performance in the
majority of cases, outperforms the alternative method considered, and displays
sufficient stability during the learning process.Comment: 41 pages, 16 figure
EVALUATION OF FUGITIVE DUST FROM CONSTRUCTION SITES IN THE CITY OF SHANGHAI
China’s cities are growing faster, more than in other countries. The presence of conspicuous number of construction
yards can affect seriously the air quality of the cities, moreover the PM10 emissions from these sources are still underestimate. A
monitoring campaign and model simulation results are presented in this paper. The aim of the project, conduct in the city of
Shanghai, was to evaluate a dust emission factor from the constructions sites. A first assessment activity was developed from
October to November 2006, in the Peng Xin Mansion construction site, where 8 PM10 sequential samplers and 2 meteorological
towers, were deployed. The data collected were used to improve a new simplify methodology, also a Gaussian plume model
AERMOD was rund. Results from the air dispersion model comes by different emission factors calculated from two procedures, one
from the AP-42 Environmental Protection Agency (EPA-USA) and the second from an empirical areal emission factor. The first
procedure assigns different sources depending on construction activities and in this case no good results were achieved. The reason
was identify in the lack of a knowledge regarding the source locations depending on schedule time, the specific employed
machinery and the detailed construction operations. The second procedure, based on the determination, from the measured data, of
an areal emission factor, gave, for 6 selected days, good results regarding the trends and the values obtained comparing with the
measured data. Considering the results obtained, we found for the construction site, one seasonal emission factor: the value is 1.8
g/(m2*sec) of PM10 emitted. At the end to better understand the role of the construction yards in the air quality budget in a city of
Shanghai we use the estimated emission factor as input in the AERMOD model
Carbon Dioxide Removal with Tuff: Experimental Measurement of Adsorption Properties and Breakthrough Modeling Using CFD Approach
Abstract This work presents the study of tuff as an alternative material for CO 2 capturing and removal by pressure swing adsorption techniques. Tuff represents an economic and environmentally sustainable alternative to commonly-used synthetic zeolites. The proposed methodology includes a laboratory characterization of the CO 2 adsorption process under different operative conditions and experimental layouts. Measured data are also used to setup computational fluid dynamics simulations of the fixed-bed adsorption column. Results can be used to define optimal design parameters needed to implement and to improve different applications for biogas upgrading (CO 2 /CH 4 ratio adjustment) or carbon capture and storage
Sentinel-2 Remote Sensed Image Classification with Patchwise Trained ConvNets for Grassland Habitat Discrimination
The present study focuses on the use of Convolutional Neural Networks (CNN or ConvNet) to classify a multi-seasonal dataset of Sentinel-2 images to discriminate four grassland habitats in the “Murgia Alta” protected site. To this end, we compared two approaches differing only by the first layer machinery, which, in one case, is instantiated as a fully-connected layer and, in the other case, results in a ConvNet equipped with kernels covering the whole input (wide-kernel ConvNet).
A patchwise approach, tessellating training reference data in square patches, was adopted. Besides assessing the effectiveness of ConvNets with patched multispectral data, we analyzed how the information needed for classification spreads to patterns over convex sets of pixels. Our results show that: (a) with an F1-score of around 97% (5 x 5 patch size), ConvNets provides an excellent tool for patch-based pattern recognition with multispectral input data without requiring special feature extraction; (b) the information spreads over the limit of a single pixel: the performance of the network
increases until 5 x 5 patch sizes are used and then ConvNet performance starts decreasing
Trends in social acceptance of renewable energy across Europe. A literature review
Social acceptance has proven to be a significant barrier in the implementation of renewable energy systems (hereinafter "RES"). While a general acceptance of RES is high, low local acceptance has hindered the development of renewable energy projects (hereinafter "REP"). This study assesses the determinants of local and general social acceptance of REP across Europe through a qualitative analysis from 25 case studies of the most significant social drivers and barriers that include all European countries. These case studies contain qualitative and quantitative analyses of the main factors for social acceptance of many representative groups including residents, stakeholders, and experts. Understanding the influences of social acceptance enables us to create strategies that will promote the development of REP by mitigating any public opposition
Assessment of energy, mobility, waste, and water management on Italian small islands
Small islands are recognized for their vulnerability to climate change. In this context, mitigation and adaptation policies are needed, but the ecological transition must be based on data. This study aims to assess the level of sustainability reached by 26 of the inhabited Italian small islands; it collects and analyzes the data and initiatives on the energy, mobility, waste, and water sectors and discusses the islands’ steps toward sustainability. The findings show that 18 of the 26 islands are not interconnected with the national grid and that the renewable sources cover less than 5% of the energy demand on 25 of the 26 islands. The number per capita of private vehicles reaches 90 cars per 100 inhabitants on three islands. The average of the separate collection of waste on the islands is 52%, which is far from the minimum recommended threshold of 65%. Pipelines or tankers on 17 of the 26 islands guarantee the water supply, and desalination plants are still not the rule, while the presence of wastewater treatment has been detected on 12 islands, and it often provides only partial treatment. An ambitious multi-stakeholder sustainability plan for each island should be developed to overcome the typical barriers of the island and to increase the building capacity in order to use economic incentives for that goal
The Bortoluzzi Mud Volcano (Ionian Sea, Italy) and its potential for tracking the seismic cycle of active faults
The Ionian Sea in southern Italy is at the center
of active interaction and convergence between the Eurasian
and African–Adriatic plates in the Mediterranean. This area
is seismically active with instrumentally and/or historically
recorded Mw > 7:0 earthquakes, and it is affected by recently
discovered long strike-slip faults across the active Calabrian
accretionary wedge. Many mud volcanoes occur on
top of the wedge. A recently discovered one (called the Bortoluzzi
Mud Volcano or BMV) was surveyed during the Seismofaults
2017 cruise (May 2017). Bathymetric backscatter
surveys, seismic reflection profiles, geochemical and earthquake
data, and a gravity core are used here to geologically,
geochemically, and geophysically characterize this structure.
The BMV is a circular feature ' 22m high and ' 1100m in
diameter with steep slopes (up to a dip of 22 ). It sits atop
the Calabrian accretionary wedge and a system of flowerlike
oblique-slip faults that are probably seismically active as
demonstrated by earthquake hypocentral and focal data. Geochemistry
of water samples from the seawater column on top
of the BMV shows a significant contamination of the bottom
waters from saline (evaporite-type) CH4-dominated crustalderived
fluids similar to the fluids collected from a mud volcano
located on the Calabria mainland over the same accretionary
wedge. These results attest to the occurrence of open
crustal pathways for fluids through the BMV down to at least
the Messinian evaporites at about 3000 m. This evidence
is also substantiated by helium isotope ratios and by comparison
and contrast with different geochemical data from
three seawater columns located over other active faults in the
Ionian Sea area. One conclusion is that the BMV may be
useful for tracking the seismic cycle of active faults through
geochemical monitoring. Due to the widespread diffusion of
mud volcanoes in seismically active settings, this study contributes
to indicating a future path for the use of mud volcanoes
in the monitoring and mitigation of natural hazards.Published1-233SR TERREMOTI - AttivitĂ dei CentriJCR Journa
RETRACE-3D PROJECT, a multidisciplinary approach for the construction of a 3D crustal model: first results and seismotectonic implications
The RETRACE-3D (centRal italy EarThquakes integRAted Crustal modEl) Project has
been launched with the ambitious goal to build, as first result, a new, robust, 3D geological
model of broad consensus of the area struck by the 2016-2018 Central Italy seismic sequencePublishedBologna3T. Sorgente sismica4T. SismicitĂ dell'Itali