Explore the vast range of titles available.

A sharp quantitative version of the anisotropic isoperimetric inequality is established, corresponding to a stability estimate for the Wulff shape of a given surface tension energy. This is achieved by exploiting mass transportation theory, especially Gromov’s proof of the isoperimetric inequality and the Brenier-McCann Theorem. A sharp quantitative version of the Brunn-Minkowski inequality for convex sets is proved as a corollary.

In this paper we consider a very general form of a non-local energy in integral form, which covers most of the usual ones (for instance, the sum of a positive and a negative power). Instead of admitting only sets, or L∞ functions, as admissible objects, we define the energy for all the Radon measures. We prove the existence of optimal measures in a wide generality, and we show that in several cases the optimal measures are actually L∞ functions, providing an a priori bound on their norm. We also derive a uniqueness result for minimizers.

A quantitative sharp form of the classical isoperimetric inequality is proved, thus giving a positive answer to a conjecture by Hall.

Cianchi et al prove a sharp quantitative version of the isoperimetric inequality in the space R^sup n^ endowed with the Gaussian measure. The isoperimetric inequality in Gauss space asserts that among all subsets of R^sup n^ with prescribed Gaussian measure, half-spaces have the least Gaussian perimeter. They also provide a geometric proof of the Gaussian isoperimetric theorem.

In dependence upon a given geometric configuration, an actual or forecasted number of vehicles arriving at an intersection can turn left or right, otherwise proceed straight through it. This article can be placed in between a research working paper, and a kind of informational brief report. Indeed, it deals with forecasting techniques for estimation of intersection turning movements. Such issue is crucial, both in network planning and in traffic engineering, while its applications span from traffic safety and environmental impacts, to signal timing, roundabout design and setting of traffic control strategies. The number of vehicles making each movement on an existing intersection can be manually collected, especially when operational analyses are undertaken. Nevertheless, when the intersection is at the planning or design stage, an estimation process is required. In its first part, this paper provides a brief literature review of some of theoretical and practical methods focused to forecast the intersection turning movements. Such a review is limited on methods used to distribute the incoming and exiting traffic volumes within the different intersection branches, then generating an estimation of the so-called intersection O/D matrix of turning flows. The second part of the paper is experimental. Two different, but similar, heuristic procedures have described. Then, they have successively applied to some selected intersection real traffic data sets, and the respective computational performances were compared. Namely, the first one is known as proportion methods, while the second one is called as the difference, or deviation, method. Each method of these two starts from an initial matrix, and through iterative steps it reaches the best estimate of the matrix of turning flows, with respect to a given distribution model. Test intersections with their related set of real traffic data have been used as input, and each of the two procedures, as described in advance, was applied to the same numeric instances. The obtained values were compared in respect to few selected performance indicators. Finally, the computational results were displayed and discussed. On this basis, some insights are drawn and useful remarks for application and future research have been addressed.

In this paper we consider a very general form of a non-local energy in integral form, which covers most of the usual ones (for instance, the sum of a positive and a negative power). Instead of admitting only sets, or L ∞ functions, as admissible objects, we define the energy for all the Radon measures. We prove the existence of optimal measures in a wide generality, and we show that in several cases the optimal measures are actually L ∞ functions, providing an a priori bound on their norm. We also derive a uniqueness result for minimizers.

Catastrophic events which are able to generate great emergency situations involving very large areas and huge networks are usually characterized by very low values of occurrence probability. This leads us to believe that individual risk perception is consequently and most likely affected by errors and it is also rather far from the effective risk level. Therefore, a priori assignment of an event risk factor is not very correct, because it can lead to large misevaluations. The risk measure of an event is a research field where some concepts belonging to psychometrics, physics and sociology are often interacting, if not mutually overlapped. This paper deals with a relatively new approach to individual risk perception and evaluation based on Prospect Theory and shows its applications for disaster and emergency management in a transport network. The main differences and advantages with other more traditional approaches are also displayed and discussed. Finally, some practical examples are referred to in order to support the strengths of Prospect Theory potential applications.

This study aims to investigate how the port waterfront structure of the city of Messina can be resilient against the stresses induced by road freight transport, and generated by the port, because of Short Sea Shipping activities. For this study, the configurational approach of the Space Syntax Analysis was used, in order to consider the relationship between the spaces of the urban grid. This urban grid has considered, on one hand as the primary matrix of the settlement processes, and on the other hand as an ordering factor for the formation of social relations between the individuals. The case study is significant due to the presence of a strong historical matrix linking the spaces of the port infrastructure with the urban structure, and such a condition appears to be common to most medium-sized Mediterranean port cities. The present work is divided into three analytical phases: (a) Structuring: geometric definition of the urban grid considering various historical periods; (b) Characterization: configurational analysis of the urban grid in the various historical periods; (c) Interaction: analysis of the relational effects of heavy freight traffic generated by the port on the configuration of the urban grid as defined above.

Illegal pedestrian crossing situations at signalized intersections are observed worldwide. The main goal of this study was to observe attributes and determine the proportion and type of pedestrian violations and dangerous crossing situations at a traffic light located in a recreational tourist urban environment, i.e. the beach town of Viareggio on the coast of Tuscany, Italy. A large signalized intersection placed close to the beach was observed for some days in Summer 2015, for several hours, both in the morning and in the afternoon, to collect data. The main aim was to identify the illegal pedestrian crossing behaviour with red traffic light. Pedestrian crossing data were recorded with a video camera. Then, the video data were processed using a semi-automated software self-written in MaTlab to extract information on different pedestrian factors. Some factors, identified in the current literature as having an influence on the proportion of violations, such as age, sex and group size, were analysed. furthermore, the impact of the amber length time on the proportion of dangerous performed crossings was studied. The obtained results highlight that pedestrians in a recreational tourist environment are generally more in compliance with traffic light than those in a weekday urban context. It is also important to pay particular attention to pedestrian yellow time (amber steady man) in order to avoid dangerous legal crossings. In fact it was often observed that pedestrians start to cross on the green walking man but end under the red light.

This paper makes an overview on modern roundabouts design and practice. Modern roundabout have become an issue of great interest over the last decade in Italy. This fact is partially drawn on the great success of roundabout traffic solutions in some European countries, where intersections design practice has changed in consequence of the performances gained with roundabouts and their general good acceptance by drivers. Modern roundabouts can have significant impacts and benefits in terms of circulation safety, delays and capacity. These quoted items form as many sections of the paper.