Assessing model credibility of CT-Based finite element model to predict bone strength

Osteoporosis is one of the major causes of mortality among the elderly. Nowadays, areal bone mineral density (aBMD) is used as diagnostic criteria for osteoporosis; however, this is a moderate predictor of the femur fracture risk and does not capture the effect of some anatomical and physiological properties on the bone strength estimation. Data from past research suggest that most fragility femur fractures occur in patients with aBMD values outside the pathological range. Subject-specific finite element models derived from computed tomography data are considered better tools to non-invasively assess hip fracture risk. In particular, the Bologna Biomechanical Computed Tomography (BBCT) is an In Silico methodology that uses a subject specific FE model to predict bone strength. Different studies demonstrated that the modeling pipeline can increase predictive accuracy of osteoporosis detection and assess the efficacy of new antiresorptive drugs. However, one critical aspect that must be properly addressed before using the technology in the clinical practice, is the assessment of the model credibility. The aim of this study was to define and perform verification and uncertainty quantification analyses on the BBCT methodology following the risk-based credibility assessment framework recently proposed in the VV-40 standard. The analyses focused on the main verification tests used in computational solid mechanics: force and moment equilibrium check, mesh convergence analyses, mesh quality metrics study, evaluation of the uncertainties associated to the definition of the boundary conditions and material properties mapping. Results of these analyses showed that the FE model is correctly implemented and solved. The operation that mostly affect the model results is the material properties mapping step. This work represents an important step that, together with the ongoing clinical validation activities, will contribute to demonstrate the credibility of the BBCT methodology.

Localizzazione e internazionalizzazione dei servizi di incrocio domanda/offerta di lavoro di Jopla S.r.l SB: tra traduzione umana e traduzione automatica

This thesis has been written as a result of the Language Toolkit project, organised by the Department of Interpreting and Translation of Forlì in collaboration with the Chamber of Commerce of Romagna. The aim of the project is to facilitate the internationalisation of small and medium enterprises in Romagna by making available to them the skills acquired by the students of the Faculty of Specialized Translation, who in turn are given the opportunity to approach an authentic professional context. Specifically, this thesis is the outcome of the 300-hour internship envisaged by the project, 75 of which were carried out at Jopla S.r.l. SB. The task assigned to the student was the translation into French of the Jopla For You web app and the Jopla PRO mobile app. This thesis consists of five chapters. The first chapter provides a general description of the Language Toolkit project and it focuses on the concept of translation into a non-native language. The second chapter outlines the theoretical context in which translation is set. Subsequently, the focus shifts to the topics of text, discourse, genre and textual typology, alongside a reflection on the applicability of these notions to web texts, and an analysis of the source text following Nord's model. The fourth chapter is dedicated to a description of the resources used in the preparation and translation phases. The fifth chapter describes the macro and micro strategies employed to carry out the translation. Furthermore, a comparative analysis between the human translation and the one provided by Google Translator is delivered. This analysis involves two methods: the first one follows the linguistic norms of the target language, while the second one relies on the error categorisation of the MQM model. Finally, the performance of Google Translate is investigated through the comparison of the results obtained from the MQM evaluation conducted in this thesis with the results obtained by Martellini (2021) in her analysis.

Quality of experience in skype video calls

Skype is one of the well-known applications that has guided the evolution of real-time video streaming and has become one of the most used software in everyday life. It provides VoIP audio/video calls as well as messaging chat and file transfer. Many versions are available covering all the principal operating systems like Windows, Macintosh and Linux but also mobile systems. Voice quality decreed Skype success since its birth in 2003 and peer-to-peer architecture has allowed worldwide diffusion. After video call introduction in 2006 Skype became a complete solution to communicate between two or more people. As a primarily video conferencing application, Skype assumes certain characteristics of the delivered video to optimize its perceived quality. However in the last years, and with the recent release of SkypeKit1, many new Skype video-enabled devices came out especially in the mobile world. This forced a change to the traditional recording, streaming and receiving settings allowing for a wide range of network and content dynamics. Video calls are not anymore based on static ‘chatting’ but mobile devices have opened new possibilities and can be used in several scenarios. For instance, lecture streaming or one-to-one mobile video conferences exhibit more dynamics as both caller and callee might be on move. Most of these cases are different from “head&shoulder” only content. Therefore, Skype needs to optimize its video streaming engine to cover more video types. Heterogeneous connections require different behaviors and solutions and Skype must face with this variety to maintain a certain quality independently from connection used. Part of the present work will be focused on analyzing Skype behavior depending on video content. Since Skype protocol is proprietary most of the studies so far have tried to characterize its traffic and to reverse engineer its protocol. However, questions related to the behavior of Skype, especially on quality as perceived by users, remain unanswered. We will study Skype video codecs capabilities and video quality assessment. Another motivation of our work is the design of a mechanism that estimates the perceived cost of network conditions on Skype video delivery. To this extent we will try to assess in an objective way the impact of network impairments on the perceived quality of a Skype video call. Traditional video streaming schemes lack the necessary flexibility and adaptivity that Skype tries to achieve at the edge of a network. Our contribution will lye on a testbed and consequent objective video quality analysis that we will carry out on input videos. We will stream raw video files with Skype via an impaired channel and then we will record it at the receiver side to analyze with objective quality of experience metrics.