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The electrical engineering has been contributed with medical science to improve the knowledge and the practical applications in disabled ones life. In general, these researches aim to restore mobility and freedom to the disabled. This paper intends to develop a system that uses Surface Electromyography and Support-Vector Machines (SVM) for the characterization of specific movements of a human arm...
This paper discusses the acquisition of image and depth data from the Microsoft Kinect's sensors for the subsequent reconstruction of a tridimensional environment, also emphasizing the stage of data pre-processing. Additionally, an algorithm that uses 3D reconstruction in order to verify if a selected trajectory is a viable route without obstacles along its path is proposed. Results from tridimensional...
This work presents an alternative method to detect events correlated to eyes opening and closing, based on electroencephalography (EEG) measured from the occipital lobe. The goal is to propose a method based on linear discriminant function to classify segments of EEG signals that contain activities originated by eyes closing. A linear discriminant function presented by Fisher is employed to detect...
The proposal of this research is to present the development of a tool that might be useful in rehabilitation, for subjects with disability, that suffer from some kind of limbs movement limitation. This tool carries a 3D Virtual Reality Environment (VRE), which emulates the movement of a healthy person, using the immersion of the subject through an avatar. To do so, and test its feasibility, pre acquired...
An Electromyogram model for the Tibialis Anterior muscle with novel firing rate equation, recruitment threshold, and spatial localisation of muscle fibres has been designed. This model has used a parallel-fibred volume conductor equation for this pennate muscle. Surface EMG was simulated using the experimental based parameters. Eight healthy subjects performed isometric dorsiflexion at 10, 20, 30,...
This article describes the development of a quantitative method for computer-aided diagnosis (CAD) of intervertebral disc degeneration according to Pfirrmann's scale, a semiquantitative scale with five degrees of degeneration, in T2-weighted magnetic resonance images of the lumbar spine. The dataset consists of images of 210 discs obtained from 42 healthy individuals. The intervertebral discs were...
Blind people face several problems related to access information. A Braille language symbol is a technique to solve this problem. A set of points which when nerve endings felt by the finger lets to form a character. With the exponential growth in technological era, the need arose to bring the users a Braille computer. For this, electromechanical devices were created, called Braille displays, allowing...
Rhythmic patterns in passwords are addressed as a kind of biometrics. Experimental results are obtained through two publicly available databases. A preprocessing step (time interval equalization) is applied to both down-down keystroke latency and key hold-down time. Improvements from this preprocessing step are shown through experiments intentionally adapted from papers by the owners of both databases...
It is a well-known fact that exposure of living tissues to ionizing radiation can result on several health problems, where cancer is probably the most complicated. This issue has been strengthening the efforts of both academy and industry to develop and improve non-invasive methods in the last decades. Electrical Impedance Tomography (EIT) is a non-invasive imaging technique that offers a vast field...
Genital organ detection of fetus in B-mode ultrasound images has a considerable significance. It is useful to know any malformations present in the genital organs and also to determine the sex of the fetus. In this paper we propose a Feature from Accelerated Segment Test (FAST) technique for approximate detection of fetal genitals in ultrasound images. FAST algorithm is capable of producing the corner...
People with severe motor disabilities present reduction or absence of motor control. However, in different stages of these conditions, some people can perform voluntary movements of low amplitude. This paper presents the development of an Human Computer Interface — HCI — for controlling an augmented and alternative communication system. The device consists of an accelerometer to capture voluntary...
The estimation of functional interdependencies within the autonomous nervous system (ANS) has gained increasing importance to quantify the relationship between neuronal and cardiac activity. The present paper introduces a biomedical signal processing approach based on computational resources to serve as a supportive tool in the characterisation of sleep. By making use of linear methods and statistical...
This research reports the identification of motor tasks in a human hand from weak myoelectric signals, aimed to control a prosthesis with individual finger flexion and wrist and grasps movements. The gestures were evaluated in two groups, independently. Four channel sEMG signals were captured on the forearm from able-body and amputees volunteers, taking into account low level contraction. Linear and...
In percutaneous surgical procedures, the precise positioning of the needle tip is of paramount relevance for good performance. Nevertheless, locate the tip of a inserted needle in a patient still represent a challenge. An imaging technique widely used for this task is the ultrasound imaging, however the low signal/noise ratio often make virtually impossible the use of simple image processing techniques...
The fields of non-invasive imaging and e-health have been increasing in the last decades, due to the need of avoiding to exposure living tissues to ionizing radiation, increasing monitoring levels of critical patients, and promoting the increasing of quality life. Furthermore, the use of image-reconstruction devices based on ionizing radiation can result on several health problems for patients in...
Stress can affect all people, regardless of age, gender or ethnicity. The human body uses stress as an adaptive response against several situations, but it can cause physical, mental or emotional distress. In stress situation the nervous system evokes the same physiological responses, whatever the type of stress and these responses cause changes in the physical, cognitive, emotional and social performance...
In this study we propose an approach for increasing mobility scooter safety by detecting and avoiding obstacles. The detection system is based on obstacle detection and implemented using infrared and ultrasonic devices. The system is fully embedded and is composed of six infrared and three ultrasonic devices which allow: far detection for crossing objects or normal speed obstacle detection; close...
One of the most promising methods to assist amputated or paralyzed patients in the control of prosthetic devices is the use of a brain computer interface (BCI). The use of a BCI allows the communication between the brain and the prosthetic device through signal processing protocols. However, due to the noisy nature of the brain signal, available signal processing protocols are unable to correctly...
Interactive robots can help people with or without disabilities. In this sense, research has been made in order to help children with motor disabilities to explore the world around them, which is important for their cognitive development. However, most of these initiatives lack on natural and intuitive interfaces, or are prohibitively expensive to be adopted in a larger scale. This paper describes...
Spasticity is a motor disorder that affects over 12 million people worldwide. Its pathophysiology is rather complex and might be caused by cortical problems or spinal cord injury, for example, and involves different circuitries and networks. The measurement of spasticity is very important for providing better support for the patients, both in diagnosis and treatment. However, there's not an agreement...
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