Related items
Showing items related by title, author, creator and subject.
-
Design and implementation of a prototype of an electrooculographic signal processing system oriented to control - by wink - the instant messaging environment Telegram for users with motor limitations in upper limbs(Signal Processing, Images and Computer Vision (STSIVA), 2015 20th Symposium on, 2015-09)This paper is based upon the design and implementation of a Human Computer Interface (HCI) as a support tool for people with upper limb disabilities, especially those with difficulties in speech, so as to interact and communicate by Instant Messaging Environments (IME). For this, we have implemented the appropriate hardware for acquisition and conditioning of the electrooculografic signal. As for the software, we have developed a wink pattern recognition algorithm composed of three processes: zero crossing technique adapted to the level of direct current (DC), comparison of the energy threshold and the Pearson correlation coefficient. Besides, a virtual keyboard was implemented to allow users to select, by means of winks, the characters that they wanted to transmit messages by the IME Telegram. Finally, the system was tested by potential users obtaining a success rate of 94.90% that proof how effective and reliable it is.Acceso restringido temporalmente
-
Correspondence Between TOVA Test Results and Characteristics of EEG Signals Acquired Through the Muse Sensor in Positions AF7–AF8(2021-01-01)This paper seeks to study the correspondence between the results of the test of variable of attention (TOVA) and the signals acquired by the Muse electroencephalogram (EEG) in the positions AF7 and AF8 of the cerebral cortex. There are a variety of research papers that estimates an index of attention in which the different characteristics in discrete signals of the brain activity were used. However, many of these results were obtained without contrasting them with standardized tests. Due to this fact, in the present work, the results will be compared with the score of the TOVA, which aims to identify an attention disorder in a person. The indicators obtained from the test are the response time variability, the average response time, and the d′ prime score. During the test, the characteristics of the EEG signals in the alpha, beta, theta, and gamma subbands such as the energy, average power, and standard deviation were extracted. For this purpose, the acquired signals are filtered to reduce the effect of the movement of the muscles near the cerebral cortex and then went through a subband decomposition process by applying transformed wavelet packets. The results show a well-marked correspondence between the parameters of the EEG signal of the indicated subbands and the visual attention indicators provided by TOVA. This correspondence was measured through Pearson’s correlation coefficient which had an average result of 0.8.Acceso restringido temporalmente
-
Improving people's accessibility through a fully actuated signal control at intersections with high density of pedestrians(Institute of Electrical and Electronics Engineers Inc., 2020-09-30)The fully actuated signal control detects the pedestrian density using sensors and, according to that, it prioritizes pedestrians crossing. One major problem, worldwide, is using fixed time traffic light as a traffic regulator at intersections with high pedestrian and vehicular volume. Lima is no exception, continuing to use this kind of traffic lights completely harms pedestrian accessibility, it increases their waiting and crossing times, it also affects road safety and service levels at the structures. The proposal on this article is to design a fully actuated signal control using logical controls that are able to perceive the pedestrian density on the refuge islands, making everything more accessible. In order to do this, a study to identify the pedestrian and vehicle volume was conducted on the Lima Panamerican highway. There was a total of 7506 pedestrians during rush hour, proving there is a large amount of people at the intersection at that time. Thereby, by using the VisVap module of the Vissim, the study managed to simulate and validate the priority control required. All in all, the results showed a remarkable improvement, the pedestrian crossing time was reduced by 6.84% and the service level of the intersection went from E to D.Acceso restringido temporalmente