A NEW HIGH-EFFICIENCY PROCEDURE FOR AGGREGATE GRADATION DETERMINATION OF THE RAILWAY BALLAST BY MEANS IMAGE RECOGNITION METHOD

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

un approccio teorico-sperimentale per la ricostruzione del profilo trasversale di rotaie usurate

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 I

Mono and stereoscopic image analysis for detecting the transverse profile of worn-out rails

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

Assessment of Functional Connectome in End-Stage Organ Disease Patients After Life-Threatening Surgery

Purpose The purpose of this study was to assess the organization of intrinsic functional brain networks (functional connectome) in neurologically asymptomatic patients with end-stage organ disease who had undergone major surgery for life-threating conditions and compare it to a control group. Materials and Methods Resting-state functional magnetic resonance imaging (rest-fMRI) was performed in 10 adult, post-operative patients with end-stage organ disease. The patients (7 men, 3 women, mean age 57.9 ± 7.4 years) had undergone: n=4 coronary artery bypass graft for heart failure, n=2 orthotopic liver transplantation for non-alcoholic cirrhotic liver failure, n=3 mitral valve repair for heart failure, n=1 pancreaticoduodenectomy for pancreatic papillary tumor. Rest-fMRI was acquired within 48 hours after intensive care unit discharge. Structural brain MR imaging was acquired with T1-weighted, T2-weighted, diffusion weighted imaging, and susceptibility weighted imaging along with 3D isotropic T1-weighted MR images. MR examinations were performed on a 3T MR scanner (Discovery 750w, General Electric Healthcare, Milwaukee, WI, USA). Ten age- and sex-matched healthy controls were studied with the same protocol. Brain functional networks were analyzed by calculating the interregional correlation of low-frequency fluctuations in spontaneous brain activity. Weighted graph-based models were employed to topologically recognize reproducibly determined large-scale functional networks, including default mode, salience, dorsal attention, sensorimotor, visual and language networks using a seed-based approach with Functional Connectivity Toolbox (CONN) (https://web.conn-toolbox.org/) running under MatLab (The MathWorks Inc., Natick, MA, USA). A p-uncorrected < 0.0025 was used to threshold connectomes for voxel-wise paired statistical analysis to take in account the lateralization effect. Network comparisons were thresholded using a false discovery rate (FDR) cluster-level correction approach in patients and controls using the MatLab function “mafdr” for p-uncorrected <0.0025 obtaining the p-FDR < 0.077. Results Functional connectivity in patients and controls was successfully assessed for the default mode, salience, dorsal attention, sensorimotor, visual, and language networks of the brain. There was statistically significant (p <0.05) reduced connectivity between seeds in the default mode, salience, sensorimotor, and language networks in patients compared to controls (Fig. 1). No acute structural lesions were observed in patients at MR imaging. Conclusion Assessment of functional connectome in end-stage organ disease patients is feasible in routine clinical setting. Rest-fMRI can demonstrate reduced connectivity of several intrinsic functional networks in critically ill, post-operative patients and it may be a useful prognostic indicator of early and long-term clinical outcome. References Ma X, et al. Aberrant functional connectome in neurologically asymptomatic patients with end-stage renal disease. PloS One 2015;10:e0121085. Lariviere S, et al. Disrupted functional network integrity and flexibility after stroke: Relation to motor impairments. NeuroImage. Clinical 2018;19:883–891. Cheng Y, et al. Longitudinal Intrinsic Brain Activity Changes in Cirrhotic Patients before and One Month after Liver Transplantation. Korean Journal of Radiology, 2017;18,370–377. Zhang XD, et al. Long-and short-range functional connectivity density alteration in non-alcoholic cirrhotic patients one month after liver transplantation: A resting-state fMRI study. Brain Research, 2015;1620:177–187. Whitfield-Gabrieli S, Nieto-Castanon A. Conn: a functional connectivity toolbox for correlated and anticorrelated brain networks. Brain Connect. 2012; 2:125-141. Additional Video Material: https://youtu.be/15lzif0MOO

Statistical Approaches to Identify Pairwise and High-Order Brain Functional Connectivity Signatures on a Single-Subject Basis

Keeping up with the shift towards personalized neuroscience essentially requires the derivation of meaningful insights from individual brain signal recordings by analyzing the descriptive indexes of physio-pathological states through statistical methods that prioritize subject-specific differences under varying experimental conditions. Within this framework, the current study presents a methodology for assessing the value of the single-subject fingerprints of brain functional connectivity, assessed both by standard pairwise and novel high-order measures. Functional connectivity networks, which investigate the inter-relationships between pairs of brain regions, have long been a valuable tool for modeling the brain as a complex system. However, their usefulness is limited by their inability to detect high-order dependencies beyond pairwise correlations. In this study, by leveraging multivariate information theory, we confirm recent evidence suggesting that the brain contains a plethora of high-order, synergistic subsystems that would go unnoticed using a pairwise graph structure. The significance and variations across different conditions of functional pairwise and high-order interactions (HOIs) between groups of brain signals are statistically verified on an individual level through the utilization of surrogate and bootstrap data analyses. The approach is illustrated on the single-subject recordings of resting-state functional magnetic resonance imaging (rest-fMRI) signals acquired using a pediatric patient with hepatic encephalopathy associated with a portosystemic shunt and undergoing liver vascular shunt correction. Our results show that (i) the proposed single-subject analysis may have remarkable clinical relevance for subject-specific investigations and treatment planning, and (ii) the possibility of investigating brain connectivity and its post-treatment functional developments at a high-order level may be essential to fully capture the complexity and modalities of the recovery

Applicazioni dell’image processing nel campo delle infrastrutture viarie. il caso della viabilità in esercizio

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

Automated Railway Signs Detection. Preliminary Results

Nowadays safety in railways is mostly achieved by automated system technologies such as ERTMS/ETCS. Nevertheless, on local railways (suburban and regional lines) several tasks still depend on the choices and actions of a human crew. With the aim to improve safety in such type of railways, this research proposes a system for the automatic detection and recognition of railway signs by means of the digital image processing technique. First field applications, carried out on the Italian railway network, show that the proposed system is very accurate (the percentage of correctly detected railway signs is about 97%), even at high train speeds

Applicazioni dell’image processing nel campo delle infrastrutture viarie. Il monitoraggio della viabilità in esercizio

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

A NEW METHODOLOGY TO ESTIMATE DEFORMATION OF LONGITUDINAL SAFETY BARRIERS

The correct sizing of storage areas in the port areas is aimed to optimizing the management of intermodal transport and to ensure efficiency and functionality to the entire port system. In this paper is proposed a simulation model for design the port storage areas taking into account many parameters like: the service time, the randomness of the arrivals process, the storage capacity in terms of TEU that can be stored (and handled) in the unit of time. The capacity of the terminal warehouse is determined by the interrelation between fixed and static parameters in the short period which are: i) the extension of the storage area; ii) the height of the overlapping batteries of container (defined also like number of “shooting”); iii) the means of movements; iv) a series of parameters that can vary the efficiency degree according to the operativity conditions of the terminal. The optimal level of use is achieved when it is employed approximately the 60-65% of the maximum storage capacity; it is kept in account, therefore, a tolerance necessary in order to make forehead to eventual peaks of traffic