41 research outputs found
HUMAN GENDER CLASSIFICATION USING KINECT SENSOR: A REVIEW
Human Gender Classification using Kinect sensor aims to classifying people’s gender based on their outward appearance. Application areas of Kinect sensor technology includes security, marketing, healthcare, and gaming. However, because of the changes in pose, attire, and illumination, gender determination with the Kinect sensor is not a trivial task. It is based on a variety of characteristics, including biological, social network, face, and body aspects. In recent years, gender classification that utilizes the Kinect sensor became a popular and essential way for accurate gender classification. A variety of methods and approaches, like machine learning, convolutional neural networks, sport vector machine (SVM), etc., have been used for gender classification using a Kinect sensor. This paper presents the state of the art for gender classification, with a focus on the features, databases, procedures, and algorithms used in it. A review of recent studies on this subject using the Kinect sensor and other technologies is provided, together with information on the variables that affect the classification\u27s accuracy. In addition, several publicly accessible databases or datasets are used by researchers to classify people by gender are covered. Finlay, this overview offers insightful information about the potential future avenues for research on Kinect-based human gender classification
Flexible Virtual Reality System for Neurorehabilitation and Quality of Life Improvement
As life expectancy is mostly increasing, the incidence of many neurological
disorders is also constantly growing. For improving the physical functions
affected by a neurological disorder, rehabilitation procedures are mandatory,
and they must be performed regularly. Unfortunately, neurorehabilitation
procedures have disadvantages in terms of costs, accessibility and a lack of
therapists. This paper presents Immersive Neurorehabilitation Exercises Using
Virtual Reality (INREX-VR), our innovative immersive neurorehabilitation system
using virtual reality. The system is based on a thorough research methodology
and is able to capture real-time user movements and evaluate joint mobility for
both upper and lower limbs, record training sessions and save electromyography
data. The use of the first-person perspective increases immersion, and the
joint range of motion is calculated with the help of both the HTC Vive system
and inverse kinematics principles applied on skeleton rigs. Tutorial exercises
are demonstrated by a virtual therapist, as they were recorded with real-life
physicians, and sessions can be monitored and configured through tele-medicine.
Complex movements are practiced in gamified settings, encouraging
self-improvement and competition. Finally, we proposed a training plan and
preliminary tests which show promising results in terms of accuracy and user
feedback. As future developments, we plan to improve the system's accuracy and
investigate a wireless alternative based on neural networks.Comment: 47 pages, 20 figures, 17 tables (including annexes), part of the MDPI
Sesnsors "Special Issue Smart Sensors and Measurements Methods for Quality of
Life and Ambient Assisted Living
Extended Capabilities of the 3-D Smith Chart With Group Delay and Resonator Quality Factor
[EN] This paper extends the capabilities of the 3-D Smith
chart for representing positive and negative differential-phase
group delay and the associated loaded resonator quality factor,
displayed simultaneously with scattering (S)-parameters. Here,
mathematical concepts, inspired from elementary differential
geometry and topology, are used to implement 3-D projections.
It is shown that a condition for a circuit to exploit negative
differential-phase group delay is that its S-parameter winding
number should be ¿ 0 (relative to its origin). Finally, exemplar
network responses that exhibit both positive and negative
differential-phase group delay and loaded resonator quality
factor are shown with the 3-D Smith chart. The convenience of
being able to simultaneously display a wider range of parameters
on one visualization platform, with the 3-D Smith chart, may help
to speed-up the design and analysis of microwave circuits by the
user.The work of A. A. Muller was supported under SIWTUNE Marie Curie Integration Grant 322162. The work of E. Sanabria-Codesal was supported in part under DGCYT Grant MTM2015-64013-P.Müller, A.; Sanabria-Codesal, E.; Moldoveanu, A.; Asavei, V.; Lucyszyn, S. (2017). Extended Capabilities of the 3-D Smith Chart With Group Delay and Resonator Quality Factor. IEEE Transactions on Microwave Theory and Techniques. 65(1):10-19. https://doi.org/10.1109/TMTT.2016.2614931S101965
Improving the Audio Game-Playing Performances of People with Visual Impairments Through Multimodal Training
As the number of people with visual impairments
(that is, those who are blind or have low vision) is continuously increasing,
rehabilitation and engineering researchers have identified the need to design sensorysubstitution
devices that would offer assistance and guidance to these people for
performing navigational tasks. Auditory and haptic cues have been shown to be an
effective approach towards creating a rich spatial representation of the environment,
so they are considered for inclusion in the development of assistive tools that would
enable people with visual impairments to acquire knowledge of the surrounding
space in a way close to the visually based perception of sighted individuals. However,
achieving efficiency through a sensory substitution device requires extensive training for
visually impaired users to learn how to process the artificial auditory cues and convert
them into spatial information. Methods: Considering all the potential advantages gamebased
learning can provide, we propose a new method for training sound localization and
virtual navigational skills of visually impaired people in a 3D audio game with hierarchical
levels of difficulty. The training procedure is focused on a multimodal (auditory
and haptic) learning approach in which the subjects have been asked to listen to 3D
sounds while simultaneously perceiving a series of vibrations on a haptic headband that
corresponds to the direction of the sound source in space. Results: The results we
obtained in a sound-localization experiment with 10 visually impaired people showed
that the proposed training strategy resulted in significant improvements in auditory
performance and navigation skills of the subjects, thus ensuring behavioral gains in the
spatial perception of the environment.Sound of Vision, Horizon 2020 nr. 643636Peer Reviewe
Relative vibrotactile spatial acuity of the torso
While tactile acuity for pressure has been extensively investigated, far less is known about acuity for vibrotactile stimulation. Vibrotactile acuity is important however, as such stimulation is used in many applications, including sensory substitution devices. We tested discrimination of vibrotactile stimulation from eccentric rotating mass motors with in-plane vibration. In 3 experiments, we tested gradually decreasing center-to-center (c/c) distances from 30 mm (experiment 1) to 13 mm (experiment 3). Observers judged whether a second vibrating stimulator (‘tactor’) was to the left or right or in the same place as a first one that came on 250 ms before the onset of the second (with a 50-ms inter-stimulus interval). The results show that while accuracy tends to decrease the closer the tactors are, discrimination accuracy is still well above chance for the smallest distance, which places the threshold for vibrotactile stimulation well below 13 mm, which is lower than recent estimates. The results cast new light on vibrotactile sensitivity and can furthermore be of use in the design of devices that convey information through vibrotactile stimulation.Peer Reviewe
A Review and Mathematical Treatment of Infinity on the Smith Chart, 3D Smith Chart and Hyperbolic Smith Chart
[EN] This work describes the geometry behind the Smith chart, recent 3D Smith chart tool and previously reported conceptual Hyperbolic Smith chart. We present the geometrical properties of the transformations used in creating them by means of inversive geometry and basic non-Euclidean geometry. The beauty and simplicity of this perspective are complementary to the classical way in which the Smith chart is taught in the electrical engineering community by providing a visual insight that can lead to new developments. Further we extend our previous work where we have just drawn the conceptual hyperbolic Smith chart by providing the equations for its generation and introducing additional properties.This research was partially funded by DGCYT grant number MTM2015-64013-P.Pérez Peñalver, MJ.; Sanabria-Codesal, E.; Moldoveanu, F.; Moldoveanu, A.; Asavei, V.; Müller, A.; Ionescu, A. (2018). A Review and Mathematical Treatment of Infinity on the Smith Chart, 3D Smith Chart and Hyperbolic Smith Chart. Symmetry (Basel). 10(10):1-13. https://doi.org/10.3390/sym10100458S113101
The Sound of Vision Project: On the Feasibility of an Audio-Haptic Representation of the Environment, for the Visually Impaired
The Sound of Vision project involves developing a sensory substitution device that is aimed at creating and conveying a rich auditory representation of the surrounding environment to the visually impaired. However, the feasibility of such an approach is strongly constrained by neural flexibility, possibilities of sensory substitution and adaptation to changed sensory input. We review evidence for such flexibility from various perspectives. We discuss neuroplasticity of the adult brain with an emphasis on functional changes in the visually impaired compared to sighted people. We discuss effects of adaptation on brain activity, in particular short-term and long-term effects of repeated exposure to particular stimuli. We then discuss evidence for sensory substitution such as Sound of Vision involves, while finally discussing evidence for adaptation to changes in the auditory environment. We conclude that sensory substitution enterprises such as Sound of Vision are quite feasible in light of the available evidence, which is encouraging regarding such projects.This work was supported by the European Union’s Horizon 2020 Research and Innovation
Programme under grant agreement No 643636 “Sound of Vision.”Peer Reviewe