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Cruising-for-parking in an urban area is a time-consuming and frustrating activity. We present four machine learning-based models to predict the parking availability of street segments in an urban area on a three-level scale, which navigator and smart-parking apps can exploit to ease and reduce the cruising phase. The models were trained with data generated by a cruising-for-parking simulator that we developed, replicating four parking behavior types (workers, residents, buyers, and visitors). The generated data is comparable to that collectible with smartphones’ sensors. We simulated 40 users moving for 200 weeks in the city area of San Giovanni in Rome. We collected information about users’ parking, unparking, and cruising actions over considered road segments at different time slots. Once a significant amount of trips were collected, we extracted ten features for each road segment at a given time slot. With the obtained dataset, which contained 761 samples, we trained and compared four supervised machine learning models that receive the history of a segment and, in return, classify the Parking Availability Level of the segment as Green, Yellow or Red. The four models were further evaluated in a different city area, San Lorenzo, and obtained very accurate results. We can predict parking availability with an accuracy above 97% for all the street segments where we collected 30 or more user actions, confirming the robustness of the simulator in generating synthetic cruising-for-parking data and the suitability of designing a Parking Availability Classifier (PAC) based on data collectible by smartphones.

Surge arresters may represent an efficient choice for limiting lightning surge effects, significantly reducing the outage rate of power lines. The present work firstly presents an efficient numerical approach suitable for insulation coordination studies based on an implicit Crank–Nicolson finite difference time domain method; then, the IEEE recommended surge arrester model is reviewed and implemented by means of a local implicit scheme, based on a set of non-linear equations, that are recast in a suitable form for efficient solution. The model is proven to ensure robustness and second-order accuracy. The implementation of the arrester model in the implicit Crank–Nicolson scheme represents the added value brought by the present study. Indeed, its preserved stability for larger time steps allows reducing running time by more than 60 % compared to the well-known finite difference time domain method based on the explicit leap-frog scheme. The reduced computation time allows faster repeated solutions, which need to be looked for on assessing the lightning performance (randomly changing, parameters such as peak current, rise time, tail time, location of the vertical leader channel, phase conductor voltages, footing resistance, insulator strength, etc. would need to be changed thousands of times).

Gasification converts biomass into syngas; however, severe cleaning processes are necessary due to the presence of tars, particulates and contaminants. The aim of this work is to propose a cleaning method system based on tar physical adsorption coupled with the production of pure H2 via a chemical looping process. Three fixed-bed reactors with a double-layer bed (NiO/Al2O3 and Fe-based particles) working in three different steps were used. First, NiO/Al2O3 is used to adsorb tar from syngas (300 °C); then, the adsorbed tar undergoes partial oxidization by NiO/Al2O3 to produce CO and H2 used for iron oxide reduction. In the third step, the reduced iron is oxidized with steam to produce pure H2 and to restore iron oxides. A double-layer fixed-bed reactor was fed alternatively by guaiacol and as tar model compounds, air and water were used. High-thermal-stability particles 60 wt% Fe2O3/40 wt% MgO synthetized by the coprecipitation method were used as Fe-based particles in six cycle tests. The adsorption efficiency of the NiO/Al2O3 bed is 98% and the gas phase formed is able to partially reduce iron, favoring the reduction kinetics. The efficiency of the process related to the H2 production after the first cycle is 35% and the amount of CO is less than 10 ppm.

In a multiuser scenario, the bit-loading, which has proven decisive in resource optimization for Power Line Communications (PLCs), has to be coupled with channel assignment to fully exploit its potential. Unfortunately, finding the most performing combination of channel and power allocation leads to integer (or mixed) programming problems, which are known to be NP-hard. To overcome the complexity of the resulting optimization problem, in this paper we propose an iterative solution that is able to guarantee both fairness and Quality of Service (QoS) to the users when the overall power consumption of the system is bounded and each subchannel emission is limited. This solution embeds a Connection Admission Control (CAC) that allows to leave out badly-connected users that otherwise would negatively affect the comprehensive system performance. Numerical results compare the presented resource allocation with the common greedy-based single user approach.

Sustainable development aims to achieve social justice, sustainable economies and environmental sustainability. However, developed nations use sustainability levels that are different from equivalents of undeveloped countries. Origin of these differences depends from standard quality of life that is permitted in each country obviously. Principles of sustainable development are invariants but, in the last period and in the developed nations, public opinion is more sensible to environmental problems. So, different weight for each element of triad (social justice, economy, environment) is adopted in each country. But many problems about energy, environment, poorness, loss of biodiversity, climate change, ozone layer, etc., cannot be resolved by a country or nation alone. And minimum value of sustainability must be agreed from countries united in world summits. Models have been achieved to monitor sustainability and to assure development. Then, a lot of indicators have been proposed as products or inputs of these models. Models together with indicators define an information system. This one is main instrument to support decision about complex problem in sustainable development. Between different information systems, Territorial Information Systems (TIS) are more adapted to manage environmental data. In the last period we used TIS support to examine new questions about different fields that are all into sustainable development area: air-pollution and urban transportation, agriculture and farm activity support, environmental impact, etc.. Finally, we presents some examples of our TIS applications: planning support dedicated to farm activity, planning rural area to guarantee effective biological culture and urban transport. Planning support consists of several parameter controls and of a programmed activity necessary to increase quality of products. Planning rural area supports politician decision and association of farms. Sustainability of transport represents a problematic issue, because its regulation involves in other fields as environment and economic structure and the same transport sustainability defines complex interaction between mobility, commerce, social justice and development.

Turbulence is still an unsolved issue with enormous implications in several fields, from the turbulent wakes on moving objects to the accumulation of heat in the built environment or the optimization of the performances of heat exchangers or mixers. This review deals with the techniques and trends in turbulent flow simulations, which can be achieved through both laboratory and numerical modeling. As a matter of fact, even if the term “experiment” is commonly employed for laboratory techniques and the term “simulation” for numerical techniques, both the laboratory and numerical techniques try to simulate the real-world turbulent flows performing experiments under controlled conditions. The main target of this paper is to provide an overview of laboratory and numerical techniques to investigate turbulent flows, useful for the research and technical community also involved in the energy field (often non-specialist of turbulent flow investigations), highlighting the advantages and disadvantages of the main techniques, as well as their main fields of application, and also to highlight the trends of the above mentioned methodologies via bibliometric analysis. In this way, the reader can select the proper technique for the specific case of interest and use the quoted bibliography as a more detailed guide. As a consequence of this target, a limitation of this review is that the deepening of the single techniques is not provided. Moreover, even though the experimental and numerical techniques presented in this review are virtually applicable to any type of turbulent flow, given their variety in the very broad field of energy research, the examples presented and discussed in this work will be limited to single-phase subsonic flows of Newtonian fluids. The main result from the bibliometric analysis shows that, as of 2021, a 3:1 ratio of numerical simulations over laboratory experiments emerges from the analysis, which clearly shows a projected dominant trend of the former technique in the field of turbulence. Nonetheless, the main result from the discussion of advantages and disadvantages of both the techniques confirms that each of them has peculiar strengths and weaknesses and that both approaches are still indispensable, with different but complementary purposes.

An efficient yet accurate procedure was developed for the seismic assessment of reinforced concrete (RC) bridges subject to chloride-induced corrosion. The procedure involves using incremental modal pushover analysis to assess corroded bridges as an alternative and less computationally demanding approach to non-linear dynamic analysis. A multi-physics finite-element analysis is performed to evaluate the effects of chloride-induced corrosion on bridge columns. In doing so, chloride ingress in concrete is numerically simulated as a diffusion process by considering the effects of temperature, humidity, corrosion-induced cover cracking and concrete aging. The estimated chloride concentration is then employed to evaluate the corrosion current density, from which the effects of corrosion on reinforcement, cracked cover concrete, confinement and plastic hinge length can be determined for subsequent non-linear static analysis. A case study of a typical bridge structure is presented. The proposed procedure can be used to assess the seismic performance of irregular RC bridges exposed to severe corrosive environments.