Comparison Between Reactive and Proactive Protocols of Wireless Sensor Networks: Railway Application

Railway is a critical application; hence, all systems that compose the railway infrastructure must meet two conditions: availability and safety. The availability ensures continuous operation of the system; on the other hand, safety is achieved when the device works properly regardless of the environmental or operating conditions. In addition, Wireless Sensor Networks (WSN) are used to perform tasks previously performed manually. However, it is necessary to analyse what protocol is appropriate for the railway industry, since availability and safety are the required attributes. In this work, a recently proposed routing protocol, the Multi-Parent Hierarchical (MPH), has been compared with a well-known protocol, the Ad-hoc On-Demand Distance Vector (AODV), in order to find the most suitable one for the railway applications. For this purpose, a simulator has been developed, which faithfully reifies the workings of a given protocol, considering a fixed, reconfigurable ad-hoc network given by the number and location of participants, and general network conditions.</p

Image-based Automated Width Measurement of Surface Cracking

The detection of cracks is an important monitoring task in civil engineering infrastructure devoted to ensuring durability, structural safety, and integrity. It has been traditionally performed by visual inspection, and the measurement of crack width has been manually obtained with a crack-width comparator gauge (CWCG). Unfortunately, this technique is time-consuming, suffers from subjective judgement, and is error-prone due to the difficulty of ensuring a correct spatial measurement as the CWCG may not be correctly positioned in accordance with the crack orientation. Although algorithms for automatic crack detection have been developed, most of them have specifically focused on solving the segmentation problem through Deep Learning techniques failing to address the underlying problem: crack width evaluation, which is critical for the assessment of civil structures. This paper proposes a novel automated method for surface cracking width measurement based on digital image processing techniques. Our proposal consists of three stages: anisotropic smoothing, segmentation, and stabilized central points by k-means adjustment and allows the characterization of both crack width and curvature-related orientation. The method is validated by assessing the surface cracking of fiber-reinforced earthen construction materials. The preliminary results show that the proposal is robust, efficient, and highly accurate at estimating crack width in digital images. The method effectively discards false cracks and detects real ones as small as 0.15 mm width regardless of the lighting conditions

Available Technologies and Commercial Devices to Harvest Energy by Human Trampling in Smart Flooring Systems: a Review

Technological innovation has increased the global demand for electrical power and energy. Accordingly, energy harvesting has become a research area of primary interest for the scientific community and companies because it constitutes a sustainable way to collect energy from various sources. In particular, kinetic energy generated from human walking or vehicle movements on smart energy floors represents a promising research topic. This paper aims to analyze the state-of-art of smart energy harvesting floors to determine the best solution to feed a lighting system and charging columns. In particular, the fundamentals of the main harvesting mechanisms applicable in this field (i.e., piezoelectric, electromagnetic, triboelectric, and relative hybrids) are discussed. Moreover, an overview of scientific works related to energy harvesting floors is presented, focusing on the architectures of the developed tiles, the transduction mechanism, and the output performances. Finally, a survey of the commercial energy harvesting floors proposed by companies and startups is reported. From the carried-out analysis, we concluded that the piezoelectric transduction mechanism represents the optimal solution for designing smart energy floors, given their compactness, high efficiency, and absence of moving parts

Enfermería como una postura política para la implementación de la justicia social

La justicia social no es excluyente de la enfermería, pues al brindar el cuidado se está resguardando la integridad del paciente al ir más allá de la persona enferma, ya que, a través de ésta, es que se posibilita la instauración de formas de poder más equitativas. Enfermería es partícipe de la experiencia del cuidado de la salud humana; pero para que esto trascienda debe evitar imponer normas, estándares y reglas, siendo más un observador que un elemento activo en la experiencia del autocuidado y respetando a su vez la autonomía propia del sujeto del cuidado. Así, al transformar la perspectiva de su autocuidado, es que la enfermería podrá generar un verdadero impacto a nivel social

A Portable Piezoelectric Tactile Terminal for Braille Readers

This paper introduces a novel concept on reading assistive technologies for the blind: the TactoBook, a system that is able to translate entire electronic books (eBooks) to Braille code and to reproduce them in portable electronic Braille terminals. The TactoBook consists of a computer-based translator that converts fast and automatically any eBook into Braille. The Braille version of the eBook is then encrypted as a file and stored in a USB memory drive which is later inserted and reproduced in a compact, lightweight, and highly-portable tactile terminal. In particular, this paper presents a piezoelectric ultrasonic actuation approach to design and implement such portable Braille terminal. Actuating mechanism, design concept, first prototype, and performance results are presented and discussed

Diseño Mecánico y Análisis Cinemático del Robot Humanoide AXIS

Este artículo presenta el desarrollo y la implementación del robot humanoide AXIS: una plataforma antropomórfica bípeda basada en el modelo biomecánico humano, el cual consiste de 4 extremidades y 20 grados de libertad (GDL). AXIS está construido enteramente de aluminio por lo que es ligero y compacto además de ser fuerte y robusto. AXIS incorpora algoritmos de inteligencia artificial que le brindan un alto grado de autonomía para realizar tareas humanas simples como caminar, girar, agacharse, acostarse y levantarse. Además, AXIS es capaz de realizar seguimiento y reconocimiento de objetos usando una videocámara en su cabeza. La principal motivación detrás de este proyecto es la creación de una plataforma propia de investigación y desarrollo en robótica humanoide: desde el estudio de la marcha bípeda y movimientos que imitan la locomoción humana hasta técnicas avanzadas de control. Este artículo se concentra en el diseño mecánico y el análisis cinemático del prototipo AXIS. En particular se simulan los espacios de trabajo y se determinan los límites de movimiento de las articulaciones con el fin de establecer un control adecuado de movimiento y evitar colisiones

SISTEMA AUTOMÁTICO DE INSPECCIÓN DE COMPONENTES MEDIANTE VISIÓN POR COMPUTADORA

ResumenEn este artículo se presenta el diseño, implementación y evaluación de un sistema de inspección de interruptores eléctricos basado en técnicas de visión por computadora. El sistema comprende dos elementos principales: una plataforma giratoria y un módulo de adquisición de imágenes digitales. El movimiento rotativo de alta precisión de la plataforma permite que dos cámaras RGB obtengan imágenes de las distintas caras de la pieza. Algoritmos morfológicos y de segmentación se aplican a las imágenes para buscar en tiempo real un sinnúmero de defectos en los interruptores. La evaluación del prototipo muestra una tasa de detección de defectos del 100% en las piezas analizadas lo que demuestra su eficiencia y pertinencia para mejorar las inspecciones visuales dentro de los procesos de manufactura de una empresa del ramo de sensores electrónicos.Palabras Claves: Detección de defectos, inspección automática, interruptores eléctricos, procesamiento digital de imágenes, visión por computadora. AUTOMATIC SYSTEM FOR INSPECTION OF COMPONENTS VIA COMPUTER VISIONAbstractThis paper presents the design, development, and experimental evaluation of an automatic inspection system for circuit breakers based on computer vision. The system basically consists of a turntable where circuit breakers are placed. Its rotating motion allows two high-resolution RGB cameras to obtain images of the different sides of the pieces. Morphological and segmentation algorithms are then applied to the images to detect in real-time flaws in the circuit breakers. An experimental evaluation of the prototype system shows a 100% detection rate which demonstrates its efficiency and pertinence to improve the visual inspections procedures inside the manufacturing processes of a company devoted to electronic sensors.Keywords: Automatic inspection, circuit breakers, computer vision, digital image processing, fault detection

An Efficient Point-Matching Method Based on Multiple Geometrical Hypotheses

Point matching in multiple images is an open problem in computer vision because of the numerous geometric transformations and photometric conditions that a pixel or point might exhibit in the set of images. Over the last two decades, different techniques have been proposed to address this problem. The most relevant are those that explore the analysis of invariant features. Nonetheless, their main limitation is that invariant analysis all alone cannot reduce false alarms. This paper introduces an efficient point-matching method for two and three views, based on the combined use of two techniques: (1) the correspondence analysis extracted from the similarity of invariant features and (2) the integration of multiple partial solutions obtained from 2D and 3D geometry. The main strength and novelty of this method is the determination of the point-to-point geometric correspondence through the intersection of multiple geometrical hypotheses weighted by the maximum likelihood estimation sample consensus (MLESAC) algorithm. The proposal not only extends the methods based on invariant descriptors but also generalizes the correspondence problem to a perspective projection model in multiple views. The developed method has been evaluated on three types of image sequences: outdoor, indoor, and industrial. Our developed strategy discards most of the wrong matches and achieves remarkable F-scores of 97%, 87%, and 97% for the outdoor, indoor, and industrial sequences, respectively

APROXIMACIÓN AL RECONOCIMIENTO DE EMOCIONES FACIALES BASADO EN POSICIÓN DE PUNTOS DE INTERÉS

ResumenCon las técnicas actuales de reconocimiento facial, es posible descubrir automáticamente las emociones de una persona a través de una imagen de su rostro. Este estudio se vale de una aplicación en línea para detectar algunos puntos de interés en imágenes de rostros que expresan alguna emoción y compara sus posiciones con las de una expresión considerada neutral. Se busca establecer una relación entre el resultado obtenido y el propuesto por la herramienta FACS de Paul Ekman para determinar la viabilidad de un algoritmo de reconocimiento de emociones, así como posibles pautas para su desarrollo.Palabras Claves: Face++, FACS, reconocimiento de emociones, reconocimiento facial. APPROACH TO THE RECOGNITION OF FACIAL EMOTIONS BASED ON POSITION OF POINTS OF INTERESTAbstractWith the current facial recognition techniques, it is possible to automatically determine an individual's emotions through a digital image of his face. The present study employs an online API to detect certain landmarks in images of faces affected by some emotion and compares their positions with those of a neutral expression. We seek to establish a relationship between the obtained results and the one proposed by Paul Ekman's FACS tool to determine the viability of an emotion recognition algorithm, as well as some possible guidelines for its development.Keywords: Emotion recognition, Face++, face recognition, FACS

An Energy Model Using Sleeping Algorithms for Wireless Sensor Networks under Proactive and Reactive Protocols: A Performance Evaluation

The continuous evolution of the Internet of Things (IoT) makes it possible to connect everyday objects to networks in order to monitor physical and environmental conditions, which is made possible due to wireless sensor networks (WSN) that enable the transfer of data. However, it has also brought about many challenges that need to be addressed, such as excess energy consumption. Accordingly, this paper presents and analyzes wireless network energy models using five different communication protocols: Ad Hoc On-Demand Distance Vector (AODV), Multi-Parent Hierarchical (MPH), Dynamic Source Routing (DSR), Low Energy Adaptive Clustering Hierarchy (LEACH) and Zigbee Tree Routing (ZTR). First, a series of metrics are defined to establish a comparison and determine which protocol exhibits the best energy consumption performance. Then, simulations are performed and the results are compared with real scenarios. The energy analysis is conducted with three proposed sleeping algorithms: Modified Sleeping Crown (MSC), Timer Sleeping Algorithm (TSA), and Local Energy Information (LEI). Thereafter, the proposed algorithms are compared by virtue of two widely used wireless technologies, namely Zigbee and WiFi. Indeed, the results suggest that Zigbee has a better energy performance than WiFi, but less redundancy in the topology links, and this study favors the analysis with the simulation of protocols with different nature. The tested scenario is implemented into a university campus to show a real network running