1,720,959 research outputs found
Design and Validation of an Electronic Unit for Monitoring Water Distribution in Plastic Pipes
No full textNeural Networks Embedded in Wearable Devices: a Preliminary Digital vs. Analog Comparison
No full textA fully connected artificial neural network (NN) for color identification (with 125 neurons and 11 color classes with inputs from an RGB sensor) was developed to study the challenges of real-time, low-power and low-latency machine learning to be embedded in wearable devices. Digital and analog approaches were compared in terms of miniaturization, power consumption, accuracy and speed. A prototype was built using a Nordic nRF52840 microcontroller with BLE, where the NN runs with an energy consumption of 6 μ J/class and sub-ms time. The feasibility of an alternative analog implementation of the NN in a dedicated integrated circuit by means of switched capacitors was evaluated through simulations, focusing in particular on the impact of weights quantization and the potentially significant saving in terms of energy dissipation (2 nJ/class)
Water Leak Monitoring by Means of a Wireless Network of Impedance Sensing Nodes
No full textWe present a novel impedance sensor to detect water leaks in water transportation pipes. The system comprises a set of impedance electrodes running along plastic pipes and measuring units. The sensor working principle is demonstrated experimentally with leaks as small as 1 liter volume. The low-power main electronic unit contains a battery, a LoRa radio module and conditioning stages of local sensors (temperature, pressure, flow rate), whereas a remote unit measures impedance to detect leak. The communication among the main unit and remote ones is achieved by the same copper electrodes employed for both impedance sensing, powering and digital communications. Low power design allows a global power consumption below 10 mW/h per day operation
IR Light Sensing at the Edges of Glasses Lenses for Invisible Eye Tracking
No full textWe propose a novel readout configuration of photo detectors (PD) employed for infrared (IR) oculography placed on the lateral edges of the standard lenses of glasses for eye tracking. They collect the amount of light reflected by the IR-illuminated eyeball and captured by the lens, which guides it towards the edges. A set of discrete photodetectors is thus hidden inside the rims and their signals are fed to an agile artificial neural network (ANN) allowing to reconstruct the direction of the incident light, thus enabling the estimation of the direction of gaze. Here we report the experimental validation of this sensing approach on both a rectangular and prescription lens. The accuracy of the ANN inference applied to the current preliminary setup with 4 PDs is ~5° and ~25° for pitch and yaw respectively. The robustness of the detection was also tested under spurious IR illumination, which is fully rejected by a differential measurement. We believe that this approach will allow the combination of aesthetics, suitable accuracy and low-power needed to shift eye tracking from specific trial conditions and devices (such as headsets with bulky external batteries) to a pervasive, full-time feature of next-generation smart glasses
A CubeSat-Sized Airborne Gamma-Ray Spectrometer for In-Flow Radioactivity Monitoring of Particulate Matter
No full textWe present a microcontroller-based in-flow airborne spectrometer to quantify the presence and activity of radioactive isotopes in particulate matter (PM). It is based on a hollow CsI(Tl) scintillator inside which air flows, thanks to a fan, and PM is captured by a micrometric filter placed in the middle, thus allowing full solid angle capture of gamma rays. The instrument is very compact, fitting in a 10 cm cube and thus being compatible with several unmanned flying vehicles, including an experimental rocket inside which it will be launched as scientific payload to evaluate the robustness of its design. Here we report the mechanical and electronics (for SiPM readout) design, as well as a preliminary characterization. Simulations have allowed to find the optimal compromise in the number and position of SiPM with an expected energy resolution better than 7% at 662 keV
A Low-Power, Non-Invasive and Contactless Eye Blink Detection Sensor Enabling Human-Machine Interfaces for Smart Eyewear Applications
No full textCUPIDO (Circuit for Unobtrusive Palpebral Interpretation and Detection Optimization) is an ultra-low-power electrostatic sensor able to convert eye blinks into digital events with a detection sensitivity up to 90.5 %. It can be easily integrated into the rims of smart glasses allowing for contactless interaction without compromising comfort and privacy (since no camera is used). Thanks to its extremely low power consumption (385.1 μW at peak during the blink), CUPIDO can extend battery life in smart glasses, allowing for continuous and real-time (detection latency of approximately 1 ms) monitoring applications like hands-free glasses control, assistive technologies, augmented reality, and drowsiness monitoring while driving
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
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