Automatic X-ray Image Segmentation and Clustering for Threat Detection

Firearms currently pose a known risk at the borders. The enormous number of X-ray images from parcels, luggage and freight coming into each country via rail, aviation and maritime presents a continual challenge to screening officers. To further improve UK capability and aid officers in their search for firearms we suggest an automated object segmentation and clustering architecture to focus officers’ attentions to high-risk threat objects. Our proposal utilizes dual-view single/ dual-energy 2D X-ray imagery and is a blend of radiology, image processing and computer vision concepts. It consists of a triple-layered processing scheme that supports segmenting the luggage contents based on the effective atomic number of each object, which is then followed by a dual-layered clustering procedure. The latter comprises of mild and a hard clustering phase. The former is based on a number of morphological operations obtained from the image-processing domain and aims at disjoining mild-connected objects and to filter noise. The hard clustering phase exploits local feature matching techniques obtained from the computer vision domain, aiming at sub-clustering the clusters obtained from the mild clustering stage. Evaluation on highly challenging single and dual-energy X-ray imagery reveals the architecture’s promising performance

H∞ LIDAR odometry for spacecraft relative navigation

Current light detection and ranging (LIDAR) based odometry solutions that are used for spacecraft relative navigation suffer from quite a few deficiencies. These include an off-line training requirement and relying on the iterative closest point (ICP) that does not guarantee a globally optimum solution. To encounter this, the authors suggest a robust architecture that overcomes the problems of current proposals by combining the concepts of 3D local feature matching with an adaptive variant of the H∞ recursive filtering process. Trials on real laser scans of an EnviSat model demonstrate that the proposed architecture affords at least one order of magnitude better accuracy compared to ICP

A Fuzzy Criticality Assessment System of Process Equipment for Optimized Maintenance Management.

yesIn modern chemical plants, it is essential to establish an effective maintenance strategy which will deliver financially driven results at optimised conditions, that is, minimum cost and time, by means of a criticality review of equipment in maintenance. In this article, a fuzzy logic-based criticality assessment system (FCAS) for the management of a local company’s equipment maintenance is introduced. This fuzzy system is shown to improve the conventional crisp criticality assessment system (CCAS). Results from case studies show that not only can the fuzzy logic-based system do what the conventional crisp system does but also it can output more criticality classifications with an improved reliability and a greater number of different ratings that account for fuzziness and individual voice of the decision-makers

CONTRIBUTION TO HYDRAULIC CHARACTERISTICS OF PLIO-PLEISTOCENE DEPOSITS OF THRIASSION PLAIN OF ATTICA

Η γεωλογική δομή της ευρύτερης περιοχής του Θριασίου Πεδίου είναι σε γενικές γραμμές πολύπλοκη και έχει επηρεασθεί σε διάφορες περιόδους από σύνθετες τεκτονικές δράσεις και τελευταία από την νεοτεκτονική, η οποία έχει δημιουργήσει πολύ σύνθετες δομές κεράτων και βυθισμάτων. Η γεωλογική και τεκτονική δομή έχει επηρεάσει τις υδρογεωλογικές συνθήκες και την κίνηση του υπόγειου νερού. Τα υδραυλικά χαρακτηριστικά των πλειολειστοκαινικών ιζημάτων διαφέρουν από θέση νσε θέση. Σε αυτό το άρθρο παρουσιάζονται αποτελέσματα αντλητικών δοκιμασιών που πραγματοποιήθηκαν στις πλειο πλειστοκαινικές αποθέσεις και προσδιορίσθηκαν τα υδραυλικά χαρακτηριστικά τους. Οι αντλήσεις πραγματοποιήθηκαν σε 8 πηγάδια και εφαρμόσθηκαν οι μέθοδοι Cooper-Jacob, Theis, Papadopoulos-Cooper, Neuman και η μέθοδος της Επαναφοράς. Οι αντλήσεις αυτές ανέδειξαν την μέθοδο της Επαναφοράς ως την πλέον αξιόπιστη. Η μεταβιβαστικότητα T κυμαίνεται μεταξύ 18-279.1 m2/d, η αποθηκευτικότητα S μεταξύ 2.5*10-3-3*10-2 και η υδραυλική αγωγιμότητα Κ κυμαίνεται μεταξύ 16-360 m3/d/m. Η έρευνα αυτή συμβάλλει, ουσιαστικά, στην προσέγγιση των υδρογεωλογικών συνθηκών που επικρατούν στο Θριάσιο Πεδίο.The geological structure of Thriassion Plain is generally complex and has been affected at different times by many tectonic activities. The last ones are the neotectonic, which caused horsts and grabens structures. Geologic and tectonic structures have influenced the hydrogeological conditions and the groundwater flow. Hydraulic characteristics of Plio-Pleistocene deposits differ throughout their extent. In this study, pumping tests in Plio-Pleistocene deposits are represented and the hydraulic characteristics transmissivity T, storativity S and hydraulic conductivity K are assigned. Pumping tests, in 8 totally wells, were conducted in the dry period. Methods as Cooper-Jacob’s, Theis’s, Papadopoulos Cooper’s and Neuman’s and last the Recovery method, are used to assign the hydraulic characteristics. These tests highlighted the Recovery method as the most reliable. Transmissivity T: 18-279.1 m2/d, storativity S: 2.5*10-3 3*10-2and hydraulic conductivity K: 0.4-25.1 m/d. Specific capacity is also determined ranging between 16-360 m3/d/m. This study contributes, essentially, in the approach of hydrogeological conditions of Thriassion Plain

CONTRIBUTION TO HYDRAULIC CHARACTERISTICS OF PLIO-PLEISTOCENE DEPOSITS OF THRIASSION PLAIN OF ATTICA

Η γεωλογική δομή της ευρύτερης περιοχής του Θριασίου Πεδίου είναι σε γενικές γραμμές πολύπλοκη και έχει επηρεασθεί σε διάφορες περιόδους από σύνθετες τεκτονικές δράσεις και τελευταία από την νεοτεκτονική, η οποία έχει δημιουργήσει πολύ σύνθετες δομές κεράτων και βυθισμάτων. Η γεωλογική και τεκτονική δομή έχει επηρεάσει τις υδρογεωλογικές συνθήκες και την κίνηση του υπόγειου νερού. Τα υδραυλικά χαρακτηριστικά των πλειολειστοκαινικών ιζημάτων διαφέρουν από θέση νσε θέση. Σε αυτό το άρθρο παρουσιάζονται αποτελέσματα αντλητικών δοκιμασιών που πραγματοποιήθηκαν στις πλειο πλειστοκαινικές αποθέσεις και προσδιορίσθηκαν τα υδραυλικά χαρακτηριστικά τους. Οι αντλήσεις πραγματοποιήθηκαν σε 8 πηγάδια και εφαρμόσθηκαν οι μέθοδοι Cooper-Jacob, Theis, Papadopoulos-Cooper, Neuman και η μέθοδος της Επαναφοράς. Οι αντλήσεις αυτές ανέδειξαν την μέθοδο της Επαναφοράς ως την πλέον αξιόπιστη. Η μεταβιβαστικότητα T κυμαίνεται μεταξύ 18-279.1 m2/d, η αποθηκευτικότητα S μεταξύ 2.5*10-3-3*10-2 και η υδραυλική αγωγιμότητα Κ κυμαίνεται μεταξύ 16-360 m3/d/m. Η έρευνα αυτή συμβάλλει, ουσιαστικά, στην προσέγγιση των υδρογεωλογικών συνθηκών που επικρατούν στο Θριάσιο Πεδίο.The geological structure of Thriassion Plain is generally complex and has been affected at different times by many tectonic activities. The last ones are the neotectonic, which caused horsts and grabens structures. Geologic and tectonic structures have influenced the hydrogeological conditions and the groundwater flow. Hydraulic characteristics of Plio-Pleistocene deposits differ throughout their extent. In this study, pumping tests in Plio-Pleistocene deposits are represented and the hydraulic characteristics transmissivity T, storativity S and hydraulic conductivity K are assigned. Pumping tests, in 8 totally wells, were conducted in the dry period. Methods as Cooper-Jacob’s, Theis’s, Papadopoulos Cooper’s and Neuman’s and last the Recovery method, are used to assign the hydraulic characteristics. These tests highlighted the Recovery method as the most reliable. Transmissivity T: 18-279.1 m2/d, storativity S: 2.5*10-3 3*10-2and hydraulic conductivity K: 0.4-25.1 m/d. Specific capacity is also determined ranging between 16-360 m3/d/m. This study contributes, essentially, in the approach of hydrogeological conditions of Thriassion Plain

A hazard analysis method for systematic identification of safety requirements for user interface software in medical devices

© Springer International Publishing AG (outside the US) 2017. Formal methods technologies have the potential to verify the usability and safety of user interface (UI) software design in medical devices, enabling significant reductions in use errors and consequential safety incidents with such devices. This however depends on comprehensive and verifiable safety requirements to leverage these techniques for detecting and preventing flaws in UI software that can induce use errors. This paper presents a hazard analysis method that extends Leveson’s System Theoretic Process Analysis (STPA) with a comprehensive set of causal factor categories, so as to provide developers with clear guidelines for systematic identification of use-related hazards associated with medical devices, their causes embedded in UI software design, and safety requirements for mitigating such hazards. The method is evaluated with a case study on the Gantry-2 radiation therapy system, which demonstrates that (1) as compared to standard STPA, our method allowed us to identify more UI software design issues likely to cause use-related hazards; and (2) the identified UI software design issues facilitated the definition of precise, verifiable safety requirements for UI software, which could be readily formalized in verification tools such as Prototype Verification System (PVS).- U.S. Food and Drug Administration(NORTE-01-0145-FEDER-000016)Sandy Weininger (FDA), Scott Thiel (Navigant Consulting, Inc.), Michelle Jump (Stryker), Stefania Gnesi (ISTI/CNR) and the CHI+MED team (www.chi-med.ac.uk) provided useful feedback and inputs. Paolo Masci’s work is supported by the North Portugal Regional Operational Programme (NORTE 2020) under the PORTUGAL 2020 Partnership Agreement, and by the European Regional Development Fund (ERDF) within Project “NORTE-01-0145-FEDER-000016”.info:eu-repo/semantics/publishedVersio