1,720,957 research outputs found
Infrared Thermography for Real-Time Assessment of the Effectiveness of Scoliosis Braces
Full text linkThis work proposes an innovative method, based on the use of low-cost infrared thermography (IRT) instrumentation, to assess in real time the effectiveness of scoliosis braces. Establishing the effectiveness of scoliosis braces means deciding whether the pressure exerted by the brace on the patient’s back is adequate for the intended therapeutic purpose. Traditionally, the evaluation of brace effectiveness relies on empirical, qualitative assessments carried out by orthopedists during routine follow-up examinations. Hence, it heavily depends on the expertise of the orthopedists involved. In the state of the art, the only objective methods used to confirm orthopedists’ opinions are based on the evaluation of how scoliosis progresses over time, often exposing people to ionizing radiation. To address these limitations, the method proposed in this work aims to provide a real-time, objective assessment of the effectiveness of scoliosis braces in a non-harmful way. This is achieved by exploiting the thermoelastic effect and correlating temperature changes on the patient’s back with the mechanical pressure exerted by the braces. A system based on this method is implemented and then validated through an experimental study on 21 patients conducted at an accredited orthopedic center. The experimental results demonstrate a classification accuracy slightly below 70% in discriminating between adequate and inadequate pressure, which is an encouraging result for further advancement in view of the clinical use of such systems in orthopedic centers
A Novel Measurement Method for Performance Assessment of Hands-Free, XR-Based Human-Machine Interfaces
Full text linkThis article presents an innovative measurement method for assessing the information transfer performance of hands-free human-machine interfaces (HMIs) based on extended reality (XR) technology. The proposed method primarily involves the design and implementation of a dedicated XR environment, which serves as a testbed for data acquisition. Following this, an experimental campaign is conducted, involving multiple acquisition cycles for different individuals. Finally, the proposed method enables extraction of two primary metrics, namely, selection accuracy and information transfer rate (ITR), indicative of the potential of the considered HMIs to transfer information. These metrics account for both intraindividual and interindividual variabilities within the HMIs, thus providing a metrologically sound assessment of performance. The proposed method is validated through a practical case study. Three NHMIs are considered: eye-tracking, head-tracking, and brain-computer interfaces (BCIs) based on steady-state visually evoked potentials (SSVEPs), as they allow hands-free interactions solely through visual observation. Without loss of generality, Microsoft HoloLens 2 and Unicorn Hybrid Black were used as XR and BCI platforms, respectively. The experimental findings obtained from eight healthy individuals allowed a comparative analysis of the performance of the three distinct HMIs, facilitating a better understanding of which interface might be more robust for a given application scenario. Overall, the proposed method represents a reliable performance assessment of innovative HMIs. This becomes increasingly significant considering the evolution of wearable HMIs and the current lack of comprehensive strategies for their characterization
Broadband Power Line Communication in Railway Traction Lines: A Survey
No full textPower line communication (PLC) is a technology that exploits existing electrical transmission and distribution networks as guiding structures for electromagnetic signal propagation. This facilitates low-rate data transmission for signaling and control operations. As the demand in terms of data rate has greatly increased in the last years, the attention paid to broadband PLC (BPLC) has also greatly increased. This concept also extended to railways as broadband traction power line communication (BTPLC), aiming to offer railway operators an alternative data network in areas where other technologies are lacking. However, BTPLC implementation faces challenges due to varying operating scenarios like urban, rural, and galleries. Hence, ensuring coverage and service continuity demands the suitable characterization of the communication channel. In this regard, the scientific literature, which is an indicator of the body of knowledge related to BTPLC systems, is definitely poor if compared to that addressed to BPLC systems installed on the electrical transmission and distribution network. The relative papers dealing with BTPLC systems and focusing on the characterization of the communication channel show some theoretical approaches and, rarely, measurements guidelines and experimental results. In addition, to the best of the author’s knowledge, there are no surveys that comprehensively address these aspects. To compensate for this lack of information, a survey of the state of the art concerning BTPLC systems and the measurement methods that assist their installation, assessment, and maintenance is presented. The primary goal is to provide the interested readers with a thorough understanding of the matter and identify the current research gaps, in order to drive future research towards the most significant issues
Expanding the Frontiers of Wearable Brain-Computer Interfaces Combining Augmented Reality and Visually Evoked Potentials
No full textGiven the increasing demand for systems that enable seamless human-computer interaction, this study presents the design and implementation of a highly wearable Brain-Computer Interface (BCI). The proposed BCI leverages Augmented Reality (AR) technology to elicit users' Steady-State Visually Evoked Potential (SSVEP) in a more immersive manner compared to traditional state-of-the-art setups. Additionally, the employment of a portable, wireless EEG acquisition system represents a significant enhancement in terms of system wearability, thereby facilitating the adoption of BCI technology also in everyday contexts
A method for the metrological characterization of eye- and head-tracking interfaces for human–machine interaction through eXtended Reality head-mounted displays
No full textGiven the increasing interest in novel and powerful Human–Machine Interaction modalities, as well as the role that eXtended Reality (XR) plays in the contemporary societal framework, this paper proposes a metrologically sound method for the experimental characterization of innovative XR-based Human–Machine Interfaces (HMIs). The aim is to thoroughly analyze the interaction between users and the digital content rendered within the XR environment, focusing on two hands-free HMIs, namely eye- and head-tracking. Starting from the acquisition of eye gaze and head pose, the proposed method encompasses the analysis of metrics such as horizontal and vertical offsets, and Euclidean distance with respect to digital reference points. From these metrics, the proposed method yields a novel figure of merit, named Maximum Number, providing insight into the optimal configuration of the XR content to maximize the information transfer. As a case study, but without loss of generalization, the XR head-mounted display Microsoft HoloLens 2 is considered. Experimental findings, derived from a campaign involving 16 subjects, contribute to a deeper understanding of the accuracy and precision in content selection, along with the number of objects that can be accommodated within the XR environment for the developed HMIs. This addresses a critical gap in current knowledge and offers valuable insights, compensating for the lack of information available in technical specifications, paving the way for the development of reliable hands-free applications in contexts with stringent requirements, such as industry or healthcare inspection tasks
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
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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