Repositório Colecção: Artigos em Actas de Congressos NacionaisArtigos em Actas de Congressos Nacionaishttps://hdl.handle.net/1822/12832024-03-29T00:40:04Z2024-03-29T00:40:04ZLong neuroprobes based on silicon dicing and iridium oxide for electrical stimulation/recordingOliveira, Maria J.Peixoto, Alexandre Coumiotis MoreiraCorreia, J. H.Gonçalves, Sandra Beatriz ToméFerreira da Silva, Alexandrehttps://hdl.handle.net/1822/899792024-03-25T20:53:25ZTítulo: Long neuroprobes based on silicon dicing and iridium oxide for electrical stimulation/recording
Autor: Oliveira, Maria J.; Peixoto, Alexandre Coumiotis Moreira; Correia, J. H.; Gonçalves, Sandra Beatriz Tomé; Ferreira da Silva, Alexandre
Resumo: This paper synthesizes the development of a new 3D neuroprobe array, constituted by microelectrodes capable of electrical stimulation and recording. The array's design relies on a bulk silicon substrate dicing technology and it comprises 6 x 6 neuroprobes with three different penetrating lengths (from 3 to 4 mm) and a 180 mu m cross-section. A reproducible fabrication method was demonstrated, capable of producing longer shafts than in previously reported arrays. In addition, sputtered titanium/iridium oxide microelectrodes have shown the required performance, with a consistent reversible electrochemical behavior and an impedance value of 145 Omega in the same frequency range as the stimulation protocols.
<b>Tipo</b>: conferencePaperHuman activity recognition systems: State of artAlpoim, LuisFerreira da Silva, AlexandreSantos, Cristinahttps://hdl.handle.net/1822/899332024-03-25T20:46:31ZTítulo: Human activity recognition systems: State of art
Autor: Alpoim, Luis; Ferreira da Silva, Alexandre; Santos, Cristina
Resumo: The present paper surveys the current research directions of the human activity recognition (HAR). Firstly, it is presented the problem of the occupational diseases and the importance of the HAR systems in the prevention of these illnesses. Then, the main steps and the most used techniques of the activity recognition process are described. Therefore, are referred some issues related to the HAR systems, that could affect both the system usability and recognition performance. By the end, the capital limitations related to these systems are discussed, as well as, some considerations to take into account in a future work.
<b>Tipo</b>: conferencePaperInertial measurement units: a brief state of the art on gait analysisRibeiro, Nuno Miguel FerreteSantos, Cristinahttps://hdl.handle.net/1822/717282021-04-14T19:53:06Z2021-04-14T14:18:53ZTítulo: Inertial measurement units: a brief state of the art on gait analysis
Autor: Ribeiro, Nuno Miguel Ferrete; Santos, Cristina
Resumo: Gait analysis systems are monitoring systems that establish a symbiosis relationship with Ambient Assisted Living (AAL) environments. Human locomotion analysis has a very important role always aiming at improving the quality of life both for individuals needing treatment or rehabilitation, as well as for healthy and elderly people. In fact, a deep and detailed knowledge about gait characteristics at a given time, and not least, monitoring and evaluating over time, will allow early diagnosis of diseases and their complications, and contribute to the decision of the treatment that should be chosen. There are several techniques used for gait measuring such as: Image Processing, Floor Sensors, and Wearable Sensors. Among the wearable sensors, has emerged an electronic device that combines multiple sensors designated by Inertial Measurement Unit (IMU). This device measures angular rate, body's specific force, and in some cases the magnetic field, and this information may be used to monitor human gait. In this article, the aim is: i) to verify the sensors that build up the IMUs, and the resulting designations that the device may have depending on the sensors it contains; ii) to list the applications of the IMUs on gait analysis; iii) to be aware of the devices available on the market and the associated commercial brands; and iv) to list the advantages and disadvantages associated with the device compared to other gait analysis systems. Concerning the literature in the scientific community, although there are some studies that focus on gait analysis or IMUs, none of them aggregates the purposes that will be addressed in this article.
<b>Tipo</b>: conferencePaper2021-04-14T14:18:53ZA preliminary strategy for fall prevention in the ASBGo smart walkerPereira, Ana RitaRibeiro, Nuno Miguel FerreteSantos, Cristinahttps://hdl.handle.net/1822/716582022-02-28T12:15:42Z2021-04-13T18:48:35ZTítulo: A preliminary strategy for fall prevention in the ASBGo smart walker
Autor: Pereira, Ana Rita; Ribeiro, Nuno Miguel Ferrete; Santos, Cristina
Resumo: Fall-related injuries affect a large part of the population and related costs. Thus, there is a concern in studying a fall prevention strategy to minimize the consequences of falls. Walkers are assistive devices used to improve the balance, stability and reduce the load on the lower limb of the user. In this sense, there is a concern to improve the safety in smart walkers and, consequently, to prevent falls in these devices. However, in this field, the only approach is to stop the walker in risk situations. So, the aim of this paper is to define a preliminary strategy to prevent a fall event in the Adaptive System Behaviour Group (ASBGo) Smart Walker. For ASBGo Smart Walker, two modes of security are discussed in this paper. One approach is based on monitoring the center of mass and changing the trajectory when a near fall is detected. The other mechanism consists only in to stop the walker when a dangerous situation is detected. The first or the second mode are activated depending if the user drives the walker with the forearm on forearm support or not.
<b>Tipo</b>: conferencePaper2021-04-13T18:48:35ZA survey of fall prevention systems implemented on smart walkersPereira, Ana RitaRibeiro, Nuno Miguel FerreteSantos, Cristinahttps://hdl.handle.net/1822/716572022-02-28T12:16:53Z2021-04-13T18:44:12ZTítulo: A survey of fall prevention systems implemented on smart walkers
Autor: Pereira, Ana Rita; Ribeiro, Nuno Miguel Ferrete; Santos, Cristina
Resumo: A large number of people die around the world in consequence of a fall. The costs related to fatal and non-fatal falls have an enormous impact on society and have been growing over the years. There are several risk factors that increase the probability of falling, such as poor balance and lower extremity weakness. Patients with balance impairment, in order to overcome these problems, use walkers. The aim of this work is to do an analysis of the fall-related strategies already implemented in a smart walker. Therefore, an online search was performed based on the literature through Scopus and Web of Science databases. A study was also conducted on a commercial level on Google, as well as a patent review on Espacenet and United States Trademark Office. It was possible to conclude that exist a concern related to the development of an approach to prevent the fall event. However, the only implemented strategy that was found throughout this research consists in stopping the walker when a near fall is detected.
<b>Tipo</b>: conferencePaper2021-04-13T18:44:12Z