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This paper suggests a methodology based on the image processing technique able to automatically calculate the vehicle traffic and its components (light vehicles, heavy vehicles and motorcycles). The method also allows to evaluate instant vehicle speeds and, where necessary, to rebuild vehicle trajectories. Traffic data obtained through the procedure described below (capacities and speeds) can be also usefully applied to estimate pollutant emissions from vehicle traffic per year; therefore, the suggested method employs the algorithms defined with CORINAIR procedures, implemented in Copert 4 software. In order to evaluate how effective is the methodology, an experiment has been carried out in a suburban area, more precisely in a motorway section approaching the International airport “Falcone e Borsellino” of Palermo in Italy.

La sovrastruttura ferroviaria durante la sua vita utile è sottoposta oltre ai carichi dinamici generati dai rotabili (azioni verticali, laterali, ecc.), anche ai carichi termici e ad azioni ambientali di varia natura. Tali sollecitazioni, interagendo sinergicamente tra loro, determinano il deterioramento della sovrastruttura ferroviaria inteso come discostamento dalla configurazione geometrica di progetto e l’usura dei singoli componenti del binario e della massicciata. Per valutare lo stato di efficienza della sovrastruttura è consuetudine far riferimento ad alcuni parametri geometrici del binario che, peraltro, permettono di formulare un giudizio oggettivo circa il livello di sicurezza offerto dalla linea ferroviaria in una data tratta. A tal riguardo, in genere, vengono esaminati distintamente in seguenti parametri geometrici [1] e [2]: i) scartamento; ii) allineamento “A”; iii) livello longitudinale “L”; iv) livello trasversale XL; v) scarto di livello trasversale SCARTXL; vi) difetto di sopraelevazione H; vii) sghembo; viii) ulteriori parametri geometrici (scartamento depurato ed in media mobile, allineamento su base 20 m, ecc.). Invece, per quanto riguarda il deterioramento dei materiali, generalmente vengono presi in esame: i) usura verticale della rotaia; ii) usura a 45° della rotaia; iii) usura orizzontale della rotaia; iv) presenza nelle campate delle rotaie di fori, fenditure, e stato delle saldature alluminotermiche ed a scintillio nelle lunghe rotaie saldate; v) tenuta degli attacchi; vi) stato delle traverse in c.a.p. ed in legno. Con riferimento allo stato di usura delle rotaie, oltre ai tradizionali metodi di auscultazione, in futuro, in ambito ferroviario, potrebbero trovare ampio impiego anche le tecniche basate sull’image processing, in grado di ricostruire con alto livello di dettaglio il profilo trasversale di una rotaia in esercizio, e dunque, di poter effettuare il confronto con il profilo originario (rotaia nuova) al fine di determinare lo stato di usura del profilato. Tale approccio metodologico, dettagliatamente descritto nei seguenti paragrafi, si basa sulle “informazioni” contenute in immagini fotografiche ad alta risoluzione delle rotaie e su specifici algoritmi che permettono di ottenere l’esatto profilo geometrico delle rotaie stesse. A new procedure for reconstructing the transverse profile of worn-out tracks by means of the image-processing technique is studied. In order to analyze the image of a track plane section, the first step of the procedure is the edge detection of the transverse profile through Canny's algorithm. This algorithm examines the behavior of the gradient operator applied to a noisy contour. Moreover, the algorithm is able to distinguish some clearer pixels near the track edge which do not belong to its micro-wrinkles, obtained from an enlargement of the upper profile of the railhead. For every chromatic plane of the analyzed image, a median filter is applied. The centroid position of the worn-out track and its contour coordinates were determined, gathered from Freeman's algorithm developed on the result formalized by relations after carrying out the proper morphological closing operations. The distances between the two profiles have been determined by the intercepts of the straight lines from the centroid of the profile IT

Purpose: High-grade glioma surgery has evolved around the principal belief that a safe maximal tumor resection improves symptoms, quality of life, and survival. Mapping brain function has been recently improved by resting-state functional magnetic resonance imaging (rest-fMRI), a novel imaging technique that explores networks connectivity at “rest.” Methods: This prospective study analyzed 10 patients with high-grade glioma in whom rest-fMRI connectivity was assessed both in single-subject and in group analysis before and after surgery. Seed-based functional connectivity analysis was performed with CONN toolbox. Network identification focused on 8 major functional connectivity networks. A voxel-wise region of interest (ROI) to ROI correlation map to assess functional connectivity throughout the whole brain was computed from a priori seeds ROI in specific resting-state networks before and after surgical resection in each patient. Results: Reliable topography of all 8 resting-state networks was successfully identified in each participant before surgical resection. Single-subject functional connectivity analysis showed functional disconnection for dorsal attention and salience networks, whereas the language network demonstrated functional connection either in the case of left temporal glioblastoma. Functional connectivity in group analysis showed wide variations of functional connectivity in the default mode, salience, and sensorimotor networks. However, salience and language networks, salience and default mode networks, and salience and sensorimotor networks showed a significant correlation (P uncorrected

The aim of this study was to introduce resting-state functional magnetic resonance imaging (rest-fMRI) capability for brain tumor surgical planning. rest-fMRI is an emerging functional neuroimaging technique potentially able to provide new insights into brain physiology and to provide useful information regarding brain tumors in preoperative and postoperative settings. rest-fMRI evaluates low-frequency fluctuations in the blood oxygen level–dependent signal while the subject is at rest during magnetic resonance imaging examination. Multiple resting-state networks have been identified, including the somatosensory, language, and visual networks, which are of primary importance for surgical planning. We discuss the feasibility of rest-fMRI examination before and after surgical resection of brain tumors in routine clinical practice and the usefulness of the information obtained for surgical planning in brain tumor resection. rest-fMRI is particularly useful for patients who are unable to cooperate with the task-based paradigm, such as children or patients who are sedated, paretic, or aphasic. Although standardization and validation of rest-fMRI are still ongoing, this technique is feasible and valuable and can be implemented for routine clinical surgical planning. © 2019 Elsevier Inc.

In order to guarantee safety and driving comfort and to maintain an efficient railway infrastructure, the first step is to carefully monitor the track geometry and wear level of the materials constituting the superstructure. To that end diagnostic trains are widely used on main lines, in that they can detect several geometric track parameters and rail wear, but under no circumstances they can yet detect ballast gradation. Due to the practical implications for the planning of maintenance operations on the railway network, this article presents a “DIP” digital image processing technique for measuring the transverse profile and corrugations of the rails as well as ballast gradation. The research was carried out in the laboratory on samples of worn-out rails taken from operational railway lines and in situ in the case of ballast analyses. For the latter, the reliability of the results obtained was assessed by comparison with available results yielded by traditional testing methods. It is shown that the proposed technique can be used not only for laboratory analyses, but most conveniently for high-efficiency in situ surveys, along with the methods traditionally adopted by the railway managing authorities thus contributing to lowering the maintenance cost associated with rail inspection.

The macroscopic mechanical behaviour of dense sands originates to a great extent from their microstructural characteristics such as the coordination number, the grain contact and the packing density indexes. The study of intergranular contacts and the reckoning of these indexes may be carried out on planar images of the grains either by means of time-consuming visual inspection assisted by CAD or by automatic image analysis. An innovative method for the automatic determination of microstructural characteristics of sands based on image analysis of thin section is proposed. Tests performed on a locked sand show that the proposed method is much more effective, convenient and faster than the usual visual inspection technique. Therefore, it can be considered an extremely useful tool for calibrating predictive models for arrangements of granular media based on computer simulations.

The mechanical characteristics of the railway superstructure are related to the properties of the ballast, and especially to the particle size distribution of its grains. Under the constant stress-strain of carriages, the ballast can deteriorate over time, and consequently it should properly be monitored for safety reasons. The equipment which currently monitors the railway superstructure (like the Italian diagnostic train Archimede) do not make any “quantitative” evaluation of the ballast. The aim of this paper is therefore to propose a new methodology for extracting railway ballast particle size distribution by means of the image processing technique. The procedure has been tested on a regularly operating Italian railway line and the results have been compared with those obtained from laboratory experiments, thus assessing how effective is the methodology which could potentially be implemented also in diagnostic trains in the near future.

Road pollutant emissions are correlated mainly to infrastructural capacity and to traffic intensity and typology. With the aim to improve road intersections performances in the last years was designed many new geometric layouts, like turbo roundabouts and flower roundabouts. The main objective of this paper is carried out a comparative analysis between conventional and innovative roundabouts in terms of CO, CO2, NO and PM2,5 vehicular emissions, evaluated by means of COPERT Software which is developed as a European tool for the calculation of emissions from the road transport sector.

The purpose of this paper is to suggest a new procedure for reconstructing the transverse profile of rails in operation by means of image-processing technique. This methodological approach is based on the “information” contained in high-resolution photographic images of tracks and on specific algorithms which allow to obtain the exact geometric profile of the rails and therefore to measure the state of the rail-head extrados wear. The analyses and the results concern rails taken from railway lines under upgrading by means of mono- and stereoscopic methods which are appropriate to be employed in laboratory applications or in high-efficiency surveys in situ.

An image analysis technique for automatic traffic sign detection and classification is proposed. This analysis makes it possible, after proper training, to detect, recognize and classify vertical road signs from video frames acquired on a moving vehicle equipped with cameras, as well as to identify anomalies with respect to road sign regulations (positioning and visibility). The experimental results show that this technique allows one to correctly detect and classify almost all vertical signs and, mainly in extra-urban environment, it can be considered as highly reliable, apart from being really versatile and user-friendly for road inventory and road maintenance purposes.

The mechanical properties of bituminous mixture strongly depend on the gradation of the aggregate that represents the mineral skeleton of the mixture, since for open and gap-graded mixtures, stresses due to vehicles in movement on the pavement are mainly transmitted through their contacts. Internal structure of bituminous mixture is, therefore, of great interest for road and infrastructure engineering and it is appropriate to study it with recently developed image analysis method. The purpose of this study was to finalize an effective analysis of asphalt section image for automatically extracting aggregate gradation without the need of separation of the bitumen from the aggregate. This paper proves that, thanks to the synergic use of different segmentation methods of the digital images taken on slices of cores from the pavement, it is possible to obtain a reliable gradation of the mineral skeleton of the mixture. The proposed methodology allows one to estimate the aggregate gradation that, otherwise, it would be necessary to establish via specially equipped laboratory, undertaking time-consuming tests that also imply health risks for the operators, due to the use of solvents and other hazardous materials.

Monitoring the wear condition of the tramway superstructure is one of the key points to guarantee an adequate safety level of the light rail transport system. The purpose of this paper is to suggest a new non-conventionalprocedure for measuring the transverse profile of rails in operation by means of image-processing technique. This methodological approach is based on the “information” contained in high-resolution photographic images of tracks and on specific algorithms which allow to obtain the exact geometric profile of the rails and therefore to measure the state of the rail-head extrados wear.

La misura dei valori assunti dai parametri geometrici del binario e lo stato di usura delle rotaie, ormai da diversi anni viene effettuata con tecniche laser ad alto rendimento e con treni diagnostici (come ad esempio i treni Archimede e Talete per le ferrovie ordinarie). Nel presente lavoro viene descritta una nuova procedura per la stima dell’usura del profilo trasversale di rotaie tranviarie in esercizio mediante la tecnica dell’image processing; tale approccio metodologico si basa sulle “informazioni” contenute in immagini fotografiche ad alta risoluzione delle rotaie e su specifici algoritmi che permettono di ottenere l’esatto profilo geometrico delle rotaie stesse e quindi di poter misurare l’usura del loro estradosso e, più in particolare, della superficie di rotolamento. Le analisi ed i risultati presentati nello studio sono relativi a ricerche svolte in laboratorio con metodiche mono e stereoscopiche effettuate su sezioni trasversali di rotaie tranviarie prelevate da linee già in esercizio. Grazie alle loro specifiche peculiarità ed alla elevata precisione nella stima dell’usura ed alla velocità di analisi, le due tecniche si prestano ad essere usate, in potenza, sia per analisi in laboratorio (dove sono di semplice applicazione le tecniche monoscopiche), sia per rilievi ad alto rendimento in situ mediante l’installazione di idonea apparecchiatura sui rotabili diagnostici (tecniche stereoscopiche) opportunamente attrezzati, eventualmente in associazione alle metodiche di auscultazione del binario tradizionalmente impiegate in ambito ferroviario.

— Over its useful life a railway track is subject to many mechanical and environmental stresses which gradually lead to its deterioration. Monitoring the wear condition of the railway superstructure is one of the key points to guarantee an adequate safety level of the railway transport system; in this field, the use of high-efficiency laser techniques has become consolidated and implemented in diagnostic trains (e.g. the “Archimede train” and the “Talete train” ) which allow to detect the track geometric parameters (gauge, alignment, longitudinal level, cross level, superelevation defect, etc.) and the state of rail wear (vertical, horizontal, 45-degree etc.) with very high accuracy. The objective of this paper is to describe a new non-conventional procedure for detecting the transverse profile of worn-out rails by means of image-processing technique. This methodological approach is based on the analysis of the information contained in high-resolution photographic images of rails and on specific algorithms which allow to obtain the exact geometric profile and the measurement of the relevant deviations compared to new rails of the same typology. The analyses and the first results, obtained from laboratory researches, concern rails cross sections taken from railway lines under upgrading. The procedure has shown high precision in the wear evaluation as well as great rapidity in being performed.

È ben noto che il comportamento meccanico microscopico delle sabbie - e in generale dei terreni granulari - trae origine dalle loro caratteristiche microstrutturali, quali, per esempio, il numero di coordinazione dei singoli grani, l’indice di contatto intergranulare (grain contact ratio) e l’indice di addensamento dei grani (packing density index). Appare, quindi, di notevole importanza la determinazione degli indici predetti con alto grado di affidabilità e di ripetibilità. Lo studio dell’assetto dei contatti intergranulari e il calcolo degli indici che lo caratterizzano, viene condotta comunemente su immagini piane dell’insieme di grani mediante esame visuale e restituzione grafica assistite da cad or per mezzo di analisi di immagini automatizzate. Nella presente memoria si propone un metodo innovativo per la determinazione automatica degli indici microstrutturali prima indicati, basato sull’analisi delle immagini. I risultati di un’applicazione a una sabbia “serrata” (locked sand) dimostrano che il metodo proposto è più efficace, rapido e conveniente rispetto alla tecnica di ispezione visiva il cui esito dipende, in misura non trascurabile, dall’operatore. It is well known that macroscopic mechanical behaviour of sand - and in general, of granular soils - originates from their microstructural characteristics such as, for example, the coordination number, the grain contact and the packing density index. It is therefore important the determination of the above mentioned with a high degree of reliability and repeatability. The study of the arrangement of intergranular contacts and the derivation of the values of pertaining indexes are carried out usually on planar images of the assemblage of grains either by means of visual inspection assisted by cad or by automatic image analysis. An innovative method for the automatic determination of particle coordination number, grain contact and packing density of sands based on image analysis of micrographs taken on thin sections of the sand is proposed in the paper. Tests performed on a locked sand show that the proposed method is more effective, fast and convenient than the usual visual inspection technique, whose output depends considerably upon the ability of the operator.

Nel settore delle infrastrutture di trasporto, si stanno sempre più sviluppando specifiche tecniche di rilievo automatico, ad alto rendimento, utilizzate per il monitoraggio dei parametrici caratteristici del traffico e di quelli geometrici dell’infrastruttura. Di particolare interesse per la loro semplicità, flessibilità d’uso, economia ed affidabilità sono le tecniche basate sull’image processing, che prevedono l’impiego sinergico di un sistema di monitoraggio e di elaborazione delle sequenze video registrate con strumentazioni digitali o analogiche. In questo ambito, le molteplici esperienze di ricerca già maturate hanno dimostrato la versatilità di tali procedure in numerose applicazioni dell’ingegneria dei trasporti. Nel presente articolo, sono descritti in modo dettagliato alcuni algoritmi matematici innovativi specificamente studiati per il monitoraggio della viabilità in esercizio, con particolare riferimento al rilievo automatizzato dei parametri cinematici dei veicoli in moto (traiettorie, velocità, accelerazioni) e al riconoscimento della segnaletica stradale di tipo verticale. Entrambe le applicazioni si prestano ad essere impiegate in modo diffuso, oltre che dai professionisti, anche dagli Enti proprietari e/o gestori di strade che, a fronte di investimenti economici relativamente modesti per acquistare le necessarie apparecchiature (hardware e software), possono monitorare di frequente l’evoluzione della domanda di traffico e lo stato di efficienza dell’arredo funzionale delle strade.

Nel settore delle infrastrutture di trasporto, si stanno sempre più sviluppando specifiche tecniche di rilievo automatico, ad alto rendimento, utilizzate per il monitoraggio dei parametrici caratteristici del traffico e di quelli geometrici dell’infrastruttura. Di particolare interesse per la loro semplicità, flessibilità d’uso, economia ed affidabilità sono le tecniche basate sull’image processing, che prevedono l’impiego sinergico di un sistema di monitoraggio e di elaborazione delle sequenze video registrate con strumentazioni digitali o analogiche. In questo ambito, le molteplici esperienze di ricerca già maturate hanno dimostrato la versatilità di tali procedure in numerose applicazioni dell’ingegneria dei trasporti. Nel presente articolo, sono descritti in modo dettagliato alcuni algoritmi matematici innovativi specificamente studiati per il monitoraggio della viabilità in esercizio, con particolare riferimento al rilievo automatizzato dei parametri cinematici dei veicoli in moto (traiettorie, velocità, accelerazioni) e al riconoscimento della segnaletica stradale di tipo verticale. Entrambe le applicazioni si prestano ad essere impiegate in modo diffuso, oltre che dai professionisti, anche dagli Enti proprietari e/o gestori di strade che, a fronte di investimenti economici relativamente modesti per acquistare le necessarie apparecchiature (hardware e software), possono monitorare di frequente l’evoluzione della domanda di traffico e lo stato di efficienza dell’arredo funzionale delle strade.