Descrizione di tre specie di Prospaltella e di una di Encarsia (Hym. Chalcididae) parassite di Aleurocanthus (Aleyrodidae)

Fra i parassiti di specie di Aleurocanthus Quaint. et Baker, che jo ebbi occasione di osservare nell'Asia meridionale e orientale, figurano tre specie nuove del genere Prospaltella e una di Encarsia, che descrivo in questa nota.Peer reviewe

Contribución al conocimiento de los Japygidae (Thysan.) de España

Nada era conocido hasta hoy de los Yapygidae de España, pero una pequeña colección del Museo Nacional de Ciencias Naturales, de Madrid, enviada para examen por mi amigo y colega D. Cándido Bolívar y Pieltain, y recogida en su mayor parte por él mismo, nos hace conocer cinco especies, de las cuales tres son descritas en esta nota como especies nuevas y otra está representada por dos variedades, también nuevas, diferentes de la forma típica italiana.Peer reviewe

Network recovery after massive failures

This paper addresses the problem of efficiently restoring sufficient resources in a communications network to support the demand of mission critical services after a large scale disruption. We give a formulation of the problem as an MILP and show that it is NP-hard. We propose a polynomial time heuristic, called Iterative Split and Prune (ISP) that decomposes the original problem recursively into smaller problems, until it determines the set of network components to be restored. We performed extensive simulations by varying the topologies, the demand intensity, the number of critical services, and the disruption model. Compared to several greedy approaches ISP performs better in terms of number of repaired components, and does not result in any demand loss. It performs very close to the optimal when the demand is low with respect to the supply network capacities, thanks to the ability of the algorithm to maximize sharing of repaired resources

On critical service recovery after massive network failures

This paper addresses the problem of efficiently restoring sufficient resources in a communications network to support the demand of mission critical services after a large-scale disruption. We give a formulation of the problem as a mixed integer linear programming and show that it is NP-hard. We propose a polynomial time heuristic, called iterative split and prune (ISP) that decomposes the original problem recursively into smaller problems, until it determines the set of network components to be restored. ISP's decisions are guided by the use of a new notion of demand-based centrality of nodes. We performed extensive simulations by varying the topologies, the demand intensity, the number of critical services, and the disruption model. Compared with several greedy approaches, ISP performs better in terms of total cost of repaired components, and does not result in any demand loss. It performs very close to the optimal when the demand is low with respect to the supply network capacities, thanks to the ability of the algorithm to maximize sharing of repaired resources

Valutazione empirica dell'influenza della risposta sismica locale sul non sincronismo del moto in superficie

Le attività riassunte in questo contributo sono svolte nell’ambito del progetto di ricerca PRIN 2008: “Effetto del non sincronismo inclusa la risposta sismica locale sulla sicurezza dei ponti”, Linea 1 EQK. In tale ambito, gli Autori hanno analizzato gli effetti dell’asincronismo del moto sismico registrato da coppie di stazioni accelerometriche ubicate, a distanze dell’ordine delle centinaia di metri, su terreni con caratteristiche lito-stratigrafiche corrispondenti ad un sito di riferimento (sito R) e su sito con amplificazione stratigrafica (sito S) corrispondente nei diversi casi alle classi di sottosuolo B, C, D della Norme Tecniche per le Costruzioni (D.M. 14/1/2008). I risultati ottenuti da queste analisi preliminari mostrano che gli spostamenti differenziali valutati secondo le prescrizioni di normativa sono mediamente maggiori di quelli misurati sperimentalmente e che la formulazione analitica adottata dalla Norma è appropriata per descrivere la dipendenza di spostamenti relativi dall’accelerazione di riferimento

Future mobility and land use scenarios: Impact assessment with an urban case study

In recent years the interest in urban mobility has grown considerably, not only due to the local increase in negative externalities generated by transport, but also because recent technological innovations are offering effective solutions especially in urban context. In particular, the introduction of Connected and Automated Vehicles (CAVs) could radically change the mobility scenario allowing, on the one hand, a widespread diffusion of shared vehicles that could feed the stations of the mass rapid transit network, improving the attractiveness of Public Transportation (PT), and on the other, the implementation of Travel Demand Management (TDM) measures on large areas of the most densely urbanized (and congested) territory of a city, without reducing accessibility and creating social exclusion. The present study aims at evaluating, through a system of Land-Use Transportation Interaction (LUTI) models, the impacts on transport demand and on population and activities location, of transportation policies oriented to both enhancing PT and restricting the individual use of the car. The case study analyzed is represented by the urban area of Rome. Several scenarios have been simulated and compared by means of sustainability indicators. Preliminary results show that the improvement of PT services, combined with the introduction of car use restriction and car free areas, do induce not only a significant modal shift towards more sustainable transportation modes, but also a limitation of urban sprawl

Kinematic and Dynamic Study of Cam Mechanisms for Bottling Machines

The main objective of this study is to analyze and optimize the cam mechanisms of the cork capper station currently in use for wine bottling machines. For each machine model considered, current cam profiles and corresponding real trajectories performed during operation are analyzed. Subsequently, various alternative laws of motion are tested to implement the same process, respecting the same precision points but modifying other parts of trajectory to improve machine dynamic performances. A series of tests carried out on a reconfigurable prototype and using different types of cork have made it possible to verify the effectiveness of the new laws of motion and to obtain the load acting on the machine at different operating speeds