A Chemistry-Inspired Framework for Achieving Consensus in Wireless Sensor Networks

The aim of this paper is to show how simple interaction mechanisms, inspired by chemical systems, can provide the basic tools to design and analyze a mathematical model for achieving consensus in wireless sensor networks, characterized by balanced directed graphs. The convergence and stability of the model are first proven by using new mathematical tools, which are borrowed directly from chemical theory, and then validated by means of simulation results, for different network topologies and number of sensors. The underlying chemical theory is also used to derive simple interaction rules that may account for practical issues, such as the estimation of the number of neighbors and the robustness against perturbations. Finally, the proposed chemical solution is validated under real-world conditions by means of a four-node hardware implementation where the exchange of information among nodes takes place in a distributed manner (with no need for any admission control and synchronism procedure), simply relying on the transmission of a pulse whose rate is proportional to the state of each sensor.Comment: 12 pages, 10 figures, submitted to IEEE Sensors Journa

Production cost model of the multi-jet-fusion technology

© IMechE 2019. The paper presents a model of the production costs of the multi-jet-fusion technology that is based on a model of production costs of the selective laser sintering technology. The model is developed using the methodology of analysis of the event-driven process chain, which consists of modeling, batch assembly, setup, building, removal, and blasting activities. Production costs of each of the activities are separated to direct (labor, material, and energy) costs and indirect (equipment, overheads, and other indirect) costs. The developed model represents a basis for the development of algorithms and software tools for the calculation of the production costs of the multi-jet-fusion technology, since it defines all the necessary inputs and calculation procedures that enable the calculation of the total costs of a batch of products. Besides, the paper presents a procedure for the estimation of production costs that are attributed to a single product or product type.The authors wish to acknowledge the support of European Commission through the project “Advanced design rules for optimal dynamic properties of additive manufacturing products – A_MADAM”, which has received funding from the European Union’s Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie grant agreement No 734455

Intensive archaeological survey at Piscina Torta:use of a low-cost RTK portable kit to materialise a UTM grid on the ground

We tested the use of a low-cost GPS RTK to set up a grid during the intensive archaeological survey of the Piscina Torta site, in the framework of the Salt and Power project of the University of Groningen. We also suggest not using a local grid but the WGS84 UTM grid and naming the single cells with the coordinates of one of its vertices. This would facilitate the use and exchange of the data (e.g. about the potsherds collected in the cell) among the scientific community

Intensive archaeological survey at Piscina Torta:use of a low-cost RTK portable kit to materialise a UTM grid on the ground

We tested the use of a low-cost GPS RTK to set up a grid during the intensive archaeological survey of the Piscina Torta site, in the framework of the Salt and Power project of the University of Groningen. We also suggest not using a local grid but the WGS84 UTM grid and naming the single cells with the coordinates of one of its vertices. This would facilitate the use and exchange of the data (e.g. about the potsherds collected in the cell) among the scientific community

Progettazione energeticamente efficiente degli Automated Storage and Retrieval Systems

In un ottica di quick response e di orientamento alla customer satisfaction gli Automated Storage and Retrieval Systems (AS/RS) risultano essere una notevole risorsa per la competitivit\ue0 aziendale; tuttavia, il continuo aumento dei costi energetici e il ruolo significativo ricoperto dalla generazione di energia nella produzione di gas serra clima-alteranti ha ultimamente posto l\u2019efficienza energetica al centro dell\u2019attenzione, ponendo l\u2019Energy efficient manufacturing e conseguentemente l\u2019Energy-aware production planning and control come obiettivo primario da perseguire. Nonostante gli AS/RS siano stati riconosciuti \u201cto make a play for sustainability\u201d in quanto, permettendo un migliore utilizzo dello spazio e contenendo i consumi di energia per il riscaldamento, il raffreddamento, l\u2019illuminazione e la ventilazione, riducono le emissioni di gas serra clima-alteranti, essi richiedono energia per gli spostamenti del trasloelevatore e questo aspetto \ue8 stato del tutto trascurato nei processi di ottimizzazione di tali strutture. Alla luce di ci\uf2, nella tesi si sono analizzate le varie problematiche riscontrate nella letteratura degli AS/RS, spostando il focus dal tradizionale orientamento alla minimizzazione del picking time, direttamente collegato al servizio percepito dal cliente, ad un\u2019ottica sostenibile, perseguendo l\u2019obiettivo di una maggiore efficienza energetica, in grado di influenzare positivamente le prestazioni sia economiche sia ambientali. Si sono indagate le politiche di controllo dell\u2019AS/RS quali lo storage assignment (capitolo 3), il dwell point (capitolo 4) e il sequencing (capitolo 5), considerando la minimizzazione del consumo energetico quale obiettivo primario di ottimizzazione, senza per\uf2 trascurare l\u2019analisi delle prestazioni di tempo, dato il loro importante legame con il servizio percepito dal cliente. Vengono pertanto proposte nuove tipologie di allocazione dei prodotti e ottimizzazioni dei cicli che deve compiere il trasloelevatore in modo da minimizzare il consumo energetico per la movimentazione. Oltre alle politiche di controllo, sono stati creati dei modelli di supporto alle decisioni di progettazione del sistema, tali modelli ottimizzano la progettazione dal punto di vista economico o ambientale (capitolo 6 e capitolo 7)

Minimum Cost Design of Cellular Networks in Rural Areas with UAVs, Optical Rings, Solar Panels and Batteries

Bringing the cellular connectivity in rural zones is a big challenge, due to the large installation costs that are incurred when a legacy cellular network based on fixed Base Stations (BSs) is deployed. To tackle this aspect, we consider an alternative architecture composed of UAV-based BSs to provide cellular coverage, ground sites to connect the UAVs with the rest of the network, Solar Panels (SPs) and batteries to recharge the UAVs and to power the ground sites, and a ring of optical fiber links to connect the installed sites. We then target the minimization of the installation costs for the considered UAV-based cellular architecture, by taking into account the constraints of UAVs coverage, SPs energy consumption, levels of the batteries and the deployment of the optical ring. After providing the problem formulation, we derive an innovative methodology to ensure that a single ring of installed optical fibers is deployed. Moreover, we propose a new algorithm, called DIARIZE, to practically tackle the problem. Our results, obtained over a set of representative rural scenarios, show that DIARIZE performs very close to the optimal solution, and in general outperforms a reference design based on fixed BSs

Nest box selection and reproduction of European Rollers in Central Italy: a 7-year study

Background: Changes and increased mechanisation of agricultural practices have influenced the biodiversity composition of farmland habitats and caused a decline of bird communities in many European countries. The removal of shrubs and large trees rich in natural cavities, has also led to a drastic decrease in nest site availability for cavity-nesting bird species. Nest-boxes are a common conservation tool used to improve nest-site availability, and have helped to reverse declines in many endangered bird populations. Nonetheless to maximize the results of such interventions it is crucial to know where nest-boxes should be sited. The objective of this study was to investigate the effectiveness of the nest-box program for the European Roller (Coracias garrulus) population of Lazio region (Central Italy). More specifically, we focused on what landscape features were preferred (or avoided) in the process of nest box selection and how they influenced population's breeding parameters. Particular attention was paid to identifying potential limitations and to provide management recommendations for future interventions. Methods: Using data from 70 nest boxes sited on power lines monitored over a 7-year period (representing 140 breeding attempts), we developed probability functions to evaluate if nest box location, in terms of distance from habitat resources and habitat composition and structure, had an effect on nest box occupancy and on the main reproductive parameters. Results: Nest boxes were more likely to be occupied if they were located near arable fields and in areas characterized by a higher amount of incoming solar radiation. Higher fledging success was associated with fallow fields and with a moderate/low habitat structural complexity. Higher breeding success was associated with solar radiation and with greater distance from urban areas. Conclusions: Our results highlight the importance of specific habitat variables in influencing nest occupancy, and show which drivers primarily affect species’ reproduction and persistence over time. Siting nest boxes in habitats where occupancy rate and fledging success is higher, such as in arable and fallow fields and on south-facing slopes where solar radiation is maximised, may help to extend the suitable habitat for rollers and facilitate its local expansion

Improved Adaptation and Survivability via Dynamic Service Composition of Ubiquitous Computing Middleware

These days, ubiquitous computing has radically changed the way users access and interact with services and content on the Internet: novel smart mobile devices and broadband wireless communication channels allow users to seamlessly access them anytime and anywhere. Middleware infrastructures to support ubiquitous computing need to support an extremely dynamic and ever-changing scenario, where novel contents/services, devices, formats, and media channels become available. Service-oriented architectures and service composition techniques have proven to be the key in designing flexible and extensible platforms that are able to reliably support ubiquitous computing. However, current trends in service composition for ubiquitous computing tend to be either too formal and, therefore, poorly used by average final users, or too vertical and poorly flexible and extensible. This paper proposes novel service composition middleware for ubiquitous computing that relies on a translucent composition model to achieve a flexible, extensible, highly-available, but also easily understandable and usable platform. The proposed system has been widely tested, benchmarked, and deployed on a number of different and heterogeneous ubiquitous scenarios