Search results for "TRADE"
showing 10 items of 1475 documents
Apparato per tracciare lo stato della superficie di un pavimento e procedimento di bilanciamento dinamico di un tale apparato
2016
Approccio teorico-sperimentale per l'analisi delle condizioni opertaive di rotatorie urbane non convenizonali.
2008
I metodi tradizionali di analisi delle intersezioni a rotatoria non consentono una valutazione attendibile delle condizioni operative del traffico in presenza di schemi organizzativi dell’intersezione, nei quali la geometria, unitamente alla molteplicità delle situazioni di traffico ed all’inserimento in contesti vincolati, induce comportamenti di guida anche molto distanti da quelli osservabili in rotatorie convenzionali. Quanto evidenziato interessa, in particolare, gli schemi circolari di intersezione in area urbana, dove risultano particolarmente diffusi e si caratterizzano per requisiti geometrico-funzionali spesso distanti da quelli propri delle rotatorie convenzionali. I vincoli loca…
Conversion of existing roundabouts into turbo-roundabouts: case studies from real world, Journal of Civil Engineering and Architecture 6(8)
2012
Compared with roundabouts the main advantages of turbo-roundabouts are the reduction in the number of potential conflicting points and the lower speed of vehicles through the intersection; they both can improve road safety conditions at the junction. Moreover, the physical delimitation among lanes limits the side-by-side accident risk. These aspects make turbo-roundabouts more appropriate than roundabouts when a higher level of safety has to be guaranteed, particularly in presence of relevant pedestrian and two-wheels traffic volumes. The present paper has three main objectives : 1) to discuss general design criteria and functional principles of turbo roundabouts; 2) to give the geometric d…
TURBO-ROUNDABOUT GENERAL DESIGN CRITERIA AND FUNCTIONAL PRINCIPLES: CASE STUDIES FROM REAL WORLD
2010
Compared with usual roundabouts the main advantages of turbo-roundabouts are the reduction in the number of potential conflicting points and the lower speed of passing vehicles through the intersection; they both can improve road safety conditions at the junction. Also, the physical delimitation among lanes limits the side-by-side accident risk. These aspects make turbo-roundabouts more appropriate than roundabouts when a higher level of safety has to be guaranteed, particularly in presence of relevant pedestrian and two-wheels traffic volumes. In a previous paper authors proposed a theoretical approach to evaluate turbo-roundabouts capacity founded on gap acceptance theory. In particular, …
Safety diagnostic method in urban circular intersections
2004
The available knowledge of traffic safety at roundabouts is not a complete reference for geometric design; where there are organizational schemes for junctions characterized by a geometric design, quite different driving behaviours are required from those that are observable at roundabouts. This is very frequent in urban areas, where the existing constraints, particularly physical ones, often render it necessary to make “compromise choices” relating to one or more geometric features of the roundabout (central island shape, circulatory roadway width, symmetry and number of the arms, entry width, etc). The objective of this study is to explain the accident phenomenology of this kind of road s…
An Italian experience on crash modeling for roundabouts
2015
In the last few years a considerable amount of safety models and evaluation tasks have been developed and specifically dedicated to roundabouts. Several safety performance functions (SPFs), indeed, have been implemented for roundabouts worldwide. Since SPFs are developed using crashes, traffic volume and other characteristics of a specific site (or geographical area), their direct transferability to other contexts different from those in which SPFs were calibrated is not always possible and, in any case, it must be done very carefully. A safety performance function cannot be used without a transferability evaluation for sites not included in the geographic area for which it was developed. S…
La spécialisation des productions et les spécialistes: Une introduction
2018
With the emergence of manufacturing based economies, specialised productions take on new dimensions during the Neolithic. Production networks progressively develop during the Neolithic and the Metal Ages and can be characterised according to their scale, how they are organised, the status of producers and the intensification of the trade of manufactured goods. This results on the one hand in mass production and on the other in the creation of highly technical objects on demand within a complex economic system of consumption and exchange. This is not seen as a linear progression but as a diversification of productions, products and know-how, the chronological and social contextualisation of …
La spécialisation des productions et les spécialistes : Session XXXIV-2 du XVIIIe congrès de l'UISPP
2020
With the emergence of manufacturing based economies, specialised productions take on new dimensions during the Neolithic. Production networks progressively develop during the Neolithic and the Metal Ages and can be characterised according to their scale, how they are organised, the status of producers and the intensification of the trade of manufactured goods. This results on the one hand in mass production and on the other in the creation of highly technical objects on demand within a complex economic system of consumption and exchange. This is not seen as a linear progression but as a diversification of productions, products and know-how, the chronological and social contextualisation of …
The evolution and ecology of multiple antipredator defences
2023
Prey seldom rely on a single type of antipredator defence, often using multiple defences to avoid predation. In many cases, selection in different contexts may favour the evolution of multiple defences in a prey. However, a prey may use multiple defences to protect itself during a single predator encounter. Such “defence portfolios” that defend prey against a single instance of predation are distributed across and within successive stages of the predation sequence (encounter, detection, identification, approach (attack), subjugation and consumption). We contend that at present, our understanding of defence portfolio evolution is incomplete, and seen from the fragmentary perspective of speci…