1,720,959 research outputs found
RadNet: A Testbed for mmWave Radar Networks
No full textHuman sensing with millimeter waves (mmWaves) is rapidly gaining momentum. In particular, mmWave radars are becoming the technology of choice in applications like contactless vital signs monitoring, people tracking, or activity recognition, when preserving the users privacy is a concern. However, single mmWave radar sensors have limited range (up to 6 - 8 m) and are affected by occlusions. For this reason, covering medium to large indoor spaces requires the deployment of multiple radar devices, i.e., radar networks. Because of the complexity of reflections produced by people moving in real life environments, the development and validation of algorithms for mmWave radar networks can only be fulfilled through extensive experimental campaigns. In this work, we present RadNet, the first experimental testbed for the easy deployment and testing of radar network algorithms. We describe its architecture and functioning and we show experimental results of a multi-radar people tracking algorithm implemented on the RadNet experimental platform
milliTRACE-IR: Contact Tracing and Temperature Screening via mmWave and Infrared Sensing
No full textSocial distancing and temperature screening have been widely employed to counteract the COVID-19 pandemic, sparking great interest from academia, industry and public administrations worldwide. While most solutions have dealt with these aspects separately, their combination would greatly benefit the continuous monitoring of public spaces and help trigger effective countermeasures. This work presents milliTRACE-IR, a joint mmWave radar and infrared imaging sensing system performing unobtrusive and privacy preserving human body temperature screening and contact tracing in indoor spaces. milliTRACE-IR combines, via a robust sensor fusion approach, mmWave radars and infrared thermal cameras. It achieves fully automated measurement of distancing and body temperature, by jointly tracking the subjects's faces in the thermal camera image plane and the human motion in the radar reference system. Moreover, milliTRACE-IR performs contact tracing: a person with high body temperature is reliably detected by the thermal camera sensor and subsequently traced across a large indoor area in a non-invasive way by the radars. When entering a new room, a subject is re-identified among several other individuals by computing gait-related features from the radar reflections through a deep neural network and using a weighted extreme learning machine as the final re-identification tool. Experimental results, obtained from a real implementation of milliTRACE-IR, demonstrate decimeter-level accuracy in distance/trajectory estimation, inter-personal distance estimation (effective for subjects getting as close as 0.2 m), and accurate temperature monitoring (max. errors of 0.5 degrees C). Furthermore, milliTRACE-IR provides contact tracing through highly accurate (95%) person re-identification, in less than 20 seconds
mmSCALE: Self-Calibration of mmWave Radar Networks from Human Movement Trajectories
No full textWe present mmSCALE, a practical self-calibration method that automatically estimates the relative position and orientation of a network of millimeter wave (mmWave) radars by post-processing the trajectories of detected targets that move within the radars' fields of view (FoVs). This is a key component of multi-device mmWave radar deployments for indoor human sensing. As commercial mmWave radars have limited range (up to 6-8 m) and are subject to occlusion, covering large indoor spaces requires multiple radars. A fully self-contained system should estimate the location and orientation of each radar with no intervention by a human operator. To solve this problem, mmSCALE fuses target detections from multiple radars, yielding median errors of 0:18 m and 2:86 degrees for radar location and orientation estimates, respectively. For this, mmSCALE requires no specific target trajectories or controlled conditions, it autonomously assesses the calibration quality over time, and is robust to occlusion and to the presence of multiple subjects
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe 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
Get PDF“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
Get PDFWe 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
An Experimental Prototype for Multistatic Asynchronous ISAC
No full textWe prototype and validate a multistatic millimeter-wave (mmWave) Integrated Sensing And Communication (ISAC) system based on IEEE 802.11ay. Compensation of the clock asynchrony between each transmitter (TX) and receiver (RX) pair is performed using the sole line-of-sight (LoS) wireless signal propagation. As a result, our system provides concurrent target tracking and micro-Doppler (μD) estimation from multiple points of view, paving the way for practical multistatic data fusion. Our results on human movement sensing, complemented with precise, quantitative ground-truth (GT) data, demonstrate the enhanced sensing capabilities of multistatic ISAC, due to the spatial diversity of the RX nodes
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe 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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