1,721,015 research outputs found
Antonio Zannoni progettista di ferrovie
No full textA oltre 100 anni dalla scomparsa verrà ricordata la figura poliedrica dell’Ing. Antonio Zannoni, Professore ordinario di Architettura Tecnica presso la Reale Scuola di applicazione per Ingegneri dell’ateneo bolognese, ingegnere capo del Comune di Bologna, consigliere comunale a Faenza, progettista di profondi rinnovamenti urbanistici ed architettonici anche al di fuori della città di Bologna, progettista della Ferrovia Faentina e artefice del restauro dell’acquedotto romano. Per sua iniziativa nacque il Museo Archeologico di Bologna
Looking behavior to vertical road signs on rural roads
No full textIn this study visual fixations at vertical road signs was tested in15 participants who drove a rural road of 15 km. Drivers gaze was assessed by mobile eye tracking glasses and vehicle performances were measured by VBOX PRO device. The route was the same for all participants and included a total of 277 vertical road signs. The results shown that only 24% of vertical signs were looked. The results were explained in terms of signs’ type, road environment conditions, traffic conditions and gende
The role of peripheral vision in vertical road sign identification and discrimination
No full textThe role of peripheral vision in road sign identification and discrimination was investigated in two studies. Peripheral vision plays an important role in road signs perception due to their lateral positioning. In the first study 20 participants identified road signs presented at five levels of horizontal eccentricity (1.1°-12.4°), and two levels of vertical eccentricity (0°-2.5°). In the second study road sign discrimination was tested in a same-different discrimination task. The first study showed that a vertical offset of 2.5° degraded proportion correct rate by 9%. Proportion correct rate decreased from 79% to 41% in the transition from 1.1° to 12.4° of horizontal offset. The second study showed an accurate discrimination for road signs presented within a horizontal offset of 6.4°. Road signs with angular shapes and prominent vertexes as triangular or cross signs were better identified in peripheral vision than signs with more compact shapes (circular signs). Practitioner summary: Vertical road signs, due to their lateral positioning, are often perceived in peripheral vision. Horizontal and vertical eccentricity negatively impacts the driver's ability to correctly identify and discriminate traffic signs. The use of singular shapes and a design with simple pictograms and large contrasting areas strongly facilitate road sign perception in peripheral vision
Le "Città 30" per una mobilità più sicura e inclusiva
No full textL'eccessiva velocità dei veicoli all’interno delle aree urbane è una delle principali cause di incidenti stradali che coinvolgono pedoni, ciclisti e motociclisti, identificati come utenti vulnerabili della strada. Ovunque è da tempo forte l’impegno per migliorare la protezione di tali utenti, anche se il problema rimane preoccupante e non può certo dirsi risolto. In Italia, nel 2019, il numero di vittime per incidenti stradali è stato pari a 3173 di cui il 46,8% pedoni, ciclisti e motociclisti. Un design stradale inadeguato associato ad un volume di traffico elevato, la coesistenza di più categorie veicolari insieme a utenti vulnerabili, e un comportamento inappropriato dei conducenti sono potenziali cause di rischio di collisione.
Al fine di creare zone più sicure e vivibili per gli utenti vulnerabili della strada, in numerose aree urbane è stato introdotto il limite di velocità di 30 km/h. Le “Città 30” hanno lo scopo di proteggere pedoni e ciclisti, migliorare la funzionalità e la sicurezza della strada e ridurre l'inquinamento atmosferico, acustico e visivo. Studi precedenti hanno dato prova dei consistenti vantaggi, in termini di sicurezza stradale, derivanti dall'introduzione del limite di velocità di 30 km/h. Un veicolo che viaggia a 50 km/h e che colpisce un pedone o un ciclista provoca un tasso di mortalità compreso tra il 55% e il 90%. Al contrario, ad una velocità di marcia di 30 km/h il tasso di mortalità è inferiore o uguale al 10%. Il 50% dei decessi di pedoni riguarda incidenti dovuti al contatto con un veicolo che viaggia ad una velocità compresa tra 50 km/h e 80 km/h e il rischio di morte a 50 km/h è più del doppio del rischio a 40 km/h, e più di cinque volte superiore al rischio a 30 km/h. A seguito dell’introduzione del limite di velocità di 30 km/h si è ottenuta una significativa riduzione della frequenza e della gravità degli incidenti sulle strade urbane. Dal confronto tra incidenti mortali o con conseguenze molto gravi all’interno di zone con e senza limite di velocità a 30 km/h è risultato che, nonostante il numero totale di incidenti nel caso di “zone 30km/h” non fosse inferiore il numero dei decessi è stato notevolmente minore. Il tema delle “Città 30” è centrale nell’evoluzione della mobilità sostenibile, ma il dibattito che lo accompagna si basa spesso su sensazioni, ‘sentito dire’ e posizioni ideologiche. È pertanto importante inquadrarlo con dati scientifici e concreti. Per questa ragione il Comune di Bologna ha monitorato le velocità di tre diverse classi veicolari (moto, macchine e autobus/veicoli pesanti) all’interno di una zona 30 km/h, lungo sei strade con caratteristiche infrastrutturali differenti, al fine di valutare il rispetto del limite previsto dalla normativa. Ciò ha reso possibile una maggiore consapevolezza delle velocità sostenute dai veicoli in questi luoghi e ha consentito di trovare soluzioni ad hoc per le strade in cui la velocità media risulta essere superiore al limite consentito, aumentando la sicurezza per ciclisti e pedoni
A Decision Support System for the safety evaluation of urban pedestrian crossings
Full text linkThis paper proposes an innovative methodology, based on a Decision Support Systems, for the safety evaluation of pedestrian
crossings without traffic lights in urban neighborhood areas. It provides an on-site inspection performed using ad-hoc data check
lists, and it allows to assign a safety rate to the pedestrian crossing, in order to define a priority list of interventions and to suggest
which features need to be improved. This new approach can be useful and easy to use for public administration managers and local
governances, when they need to allocate limited financial resources to several pedestrian crossings. It has been applied to 10
pedestrian crossings on two roads in the urban area of Bologna and the resulted ranking list has been used by the Municipality of
Bologna in its Urban Road Safety Plan 2016-201
Safety roads: the analysis of driving behaviour and the effects on the infrastructural design
Full text linkRoad design should ensure the correct behaviour of drivers in terms of speed and level of attention. Nevertheless, in some cases
users are not able to visualize the carriageway enough correctly, owing to the misled road layout or the loss of visibility.
In this research, road safety management was assessed with the driving and visual behaviour of users, considering the impact of
different configurations of pedestrian crossings and road signs in order to reduce accidents. Even if users focus their attention on
the zebra crossing (60%) and the vertical sign (24%), 16% of them have had no perception of the pedestrian crossings. This result
shows how pedestrian crossings represent critical points that could compromise the safety of vulnerable users also in relation to
speed. In fact, driving behaviour highlights 50 km/h of the average speed at 100 meters before the crosswalk, which allows having
a too short time to stop the vehicle in safety. Moreover, the maximum speed underlines that users drive beyond the limit imposed
by the road’s rules. It is thus necessary to require the implementation of road infrastructure so as to modify the driving behaviour.
Starting from the Road Safety Review, it was then possible to detect the critical issues and correlate a visual and kinematic analysis
so as to intervene accurately
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Driver's visual attention to different categories of roadside advertising signs
Full text linkRoadside advertising signs are a salient potential source of driver's distraction. Previous research has mainly investigated driver's visual attention to billboards, which represents only one category of advertising signs. In this study, driver's visual attention was assessed in a naturalistic driving setting for six categories of roadside advertising signs: vendor signs, billboards, movable display boards, single and multiple commercial directional signs, and gas price LED displays. Fixation rate, fixation duration, fixation distance and driving speed were assessed in a sample of 15 drivers along a 30-km route including a total of 154 advertising signs belonging to the six categories described above. The role of clearance from the road, elevation, height, width, surface, number and size of characters, total number of characters, side of the road (driving side, opposite side), context (rural, urban), were also considered. Overall 24% of the roadside advertising signs were fixated. Fixation rate was significantly influenced by sign category, clearance from the road and number of characters. Median value for fixation duration was 297 ms. Fixation duration was significantly influenced by speed, elevation from road level, number of medium size characters, and was higher in the rural context. Median value for fixation distance was 58.10 m, and was significantly influenced by advertising sign category, character count and speed
The safety and conspicuity of pedestrian crossing at roundabouts: The effect of median refuge island and zebra markings
Full text linkRoundabouts are one of the most used road intersections because, compared to signalized
ones, they reduce conflict points between traffic flows and moderate driving speed. Great
attention should also be paid to vulnerable road users at roundabouts. According to accident
statistics, in fact, accessibility of pedestrians and cyclists is not always ensured.
This paper has evaluated the effects on the visibility of pedestrian crossing before and
after the displacement of zebra markings, moved before intersections, and the introduction
of media refuge islands and ‘‘Yield here to pedestrians” vertical signs. The above effects
have been assessed by before-after analysis of speed and visual behaviour of drivers
approaching the crosswalk.
Moreover, the analysis of the drivers’ eye movements has highlighted the most salient
elements of the pedestrian crossing. The relation between the drivers’ visual behaviour
and the vehicle speed have also been calculated. Results have confirmed that the intervention
carried out has increased both visibility and safety of the studied pedestrian crosswalks.
Zebra markings and the median refuge island have turned out to be the most glanced elements,
respectively seen by 93.75% and 56.25% of the drivers, followed by the ‘‘Yield here
to pedestrians” vertical sign. The mean distance of first fixation of the crosswalk increased
from 21.98 m before the intervention, to 40.69 m after it. The drivers perceived the pedestrian
crossings from a longer distance after the intervention, and they continued to glance
at the crosswalk while approaching it, enhancing their visual attention
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