764 research outputs found

    Imaging of the Building Contours with Through the Wall UWB Radar System

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    Any actual information about a building interior can be very useful before entering a dangerous area. It can be used to plan strategies in many rescue and security applications. The paper deals with imaging of the inner and outer building contours from the outside using through the wall UWB radar. The whole processing chain for obtaining the contours of a scanned building is explained. The image processing method of highlighting the building walls using Hough transform with assumed knowledge of the direction of walls is presented. The algorithm was tested on real measurement data acquired from a M-sequence UWB radar system

    Exploring EEG Features in Cross-Subject Emotion Recognition

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    Recognizing cross-subject emotions based on brain imaging data, e.g., EEG, has always been difficult due to the poor generalizability of features across subjects. Thus, systematically exploring the ability of different EEG features to identify emotional information across subjects is crucial. Prior related work has explored this question based only on one or two kinds of features, and different findings and conclusions have been presented. In this work, we aim at a more comprehensive investigation on this question with a wider range of feature types, including 18 kinds of linear and non-linear EEG features. The effectiveness of these features was examined on two publicly accessible datasets, namely, the dataset for emotion analysis using physiological signals (DEAP) and the SJTU emotion EEG dataset (SEED). We adopted the support vector machine (SVM) approach and the "leave-one-subject-out" verification strategy to evaluate recognition performance. Using automatic feature selection methods, the highest mean recognition accuracy of 59.06% (AUC = 0.605) on the DEAP dataset and of 83.33% (AUC = 0.904) on the SEED dataset were reached. Furthermore, using manually operated feature selection on the SEED dataset, we explored the importance of different EEG features in cross-subject emotion recognition from multiple perspectives, including different channels, brain regions, rhythms, and feature types. For example, we found that the Hjorth parameter of mobility in the beta rhythm achieved the best mean recognition accuracy compared to the other features. Through a pilot correlation analysis, we further examined the highly correlated features, for a better understanding of the implications hidden in those features that allow for differentiating cross-subject emotions. Various remarkable observations have been made. The results of this paper validate the possibility of exploring robust EEG features in cross-subject emotion recognition

    Modality effects in implicit artificial grammar learning: An EEG study

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    Recently, it has been proposed that sequence learning engages a combination of modality-specific operating networks and modality-independent computational principles. In the present study, we compared the behavioural and EEG outcomes of implicit artificial grammar learning in the visual vs. auditory modality. We controlled for the influence of surface characteristics of sequences (Associative Chunk Strength), thus focusing on the strictly structural aspects of sequence learning, and we adapted the paradigms to compensate for known frailties of the visual modality compared to audition (temporal presentation, fast presentation rate). The behavioural outcomes were similar across modalities. Favouring the idea of modality-specificity, ERPs in response to grammar violations differed in topography and latency (earlier and more anterior component in the visual modality), and ERPs in response to surface features emerged only in the auditory modality. In favour of modality-independence, we observed three common functional properties in the late ERPs of the two grammars: both were free of interactions between structural and surface influences, both were more extended in a grammaticality classification test than in a preference classification test, and both correlated positively and strongly with theta event-related-synchronization during baseline testing. Our findings support the idea of modality-specificity combined with modality-independence, and suggest that memory for visual vs. auditory sequences may largely contribute to cross-modal differences. (C) 2018 Elsevier B.V. All rights reserved.Max Planck Institute for Psycholinguistics; Donders Institute for Brain, Cognition and Behaviour; Fundacao para a Ciencia e Tecnologia [PTDC/PSI-PC0/110734/2009, UID/BIM/04773/2013, CBMR 1334, PEst-OE/EQB/1A0023/2013, UM/PSI/00050/2013

    Detection of emotions in Parkinson's disease using higher order spectral features from brain's electrical activity

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    Non-motor symptoms in Parkinson's disease (PD) involving cognition and emotion have been progressively receiving more attention in recent times. Electroencephalogram (EEG) signals, being an activity of central nervous system, can reflect the underlying true emotional state of a person. This paper presents a computational framework for classifying PD patients compared to healthy controls (HC) using emotional information from the brain's electrical activity

    Optimizing the Prioritization of Natural Disaster Recovery Projects

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    Prioritizing reconstruction projects to recover a base from a natural disaster is a complicated and arduous process that involves all levels of leadership. The project prioritization phase of base recovery has a direct affect on the allocation of funding, the utilization of human resources, the obligation of projects, and the overall speed and efficiency of the recovery process. The focus of this research is the development of an objective and repeatable process for optimizing the project prioritization phase of the recovery effort. This work will focus on promoting objectivity in the project prioritizing process, improving the communication of the overall base recovery requirement, increasing efficiency in utilizing human and monetary resources, and the creation of a usable and repeatable decision-making tool based on Value-Focused Thinking and integer programming methods

    Threat modulates neural responses to looming visual stimuli

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    Objects on a collision course with an observer produce a specific pattern of optical expansion on the retina known as looming, which in theory exactly specifies the time-to-collision (TTC) of approaching objects. We recently demonstrated that the affective content of looming stimuli influences perceived TTC, with threatening objects judged as approaching sooner than non-threatening objects. Here, we investigated the neural mechanisms by which perceived threat modulates spatiotemporal perception. Participants judged the TTC of threatening (snakes, spiders) or non-threatening (butterflies, rabbits) stimuli, which expanded in size at a rate indicating one of five TTCs. We analysed visual-evoked potentials (VEPs) and oscillatory neural responses measured with electroencephalography (EEG). The arrival time of threatening stimuli was underestimated compared to non-threatening stimuli, though an interaction suggested that this underestimation was not constant across TTCs. Further, both speed of approach and threat modulated both VEPs and oscillatory responses. Speed of approach modulated the N1 parietal and oscillations in the beta band. Threat modulated several VEP components (P1, N1 frontal, N1 occipital, EPN and LPP) and oscillations in the alpha and high gamma band. The results for the high gamma band suggest an interaction between these two factors. Previous evidence suggests that looming stimuli activate sensorimotor areas, even in absence of an intended action. Our results show that threat disrupts the synchronization over the sensorimotor areas that are likely activated by the presentation of a looming stimulus

    Monitorování tréninku rychlosti u fotbalistů U13

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    Název: Monitorování tréninku rychlosti u fotbalistů U13 Cíl: Popsat v rámci literární rešerše základní atributy mládežnického fotbalu a na základě průřezové studie ve formě jednorázového testování monitorovat indikátory kondiční připravenosti hráčů kategorie U13 ve vybraném klubu se zvláštním zřetelem na rychlost. Metody: Výzkumný soubor tvořilo 17 hráčů SK Aaritm Praha z kategorie U13. Pro testování byla zvolena jedná testová baterie, která obsahovala 5 různých testů. Test na akcelerační rychlost (sprint na 10 m s mezičasem na 5 m). Test na absolutní lokomoční rychlost (letmý sprint na 20 m letmo). Test pro zjištění rychlosti a obratnosti (505-agility test). Test pro zjištění explosivní síly dolních končetin (vertikální výskok z místa) a test pro zjištění explosivní síly horních končetin (hod s medicinbal zponad hlavy s dvěma rukama). K vyhodnocení naměřených dat byl použit párový oboustranný (dvoj ocasní) t-test a interval spolehlivosti studentova rozdělení s 95% pravděpodobností. Výsledky: Výsledky ukázaly, že výrazně zhoršení rychlosti nastalo s přibývajícími pokusy v běžeckých testech, ale při silových testech průměrná hodnota zůstala konstantní nebo se zlepšila s přibývajícím pokusem. Zobecněním výsledků se průměry dvou pokusů ze tří jednoho testu shodovaly s naší určenou pravděpodobností,...Title: Monitoring of speed training of soccer players U13 Objective: In the literature research to describe the basic atributes of youth soccer and on the basis of cross - sectional study in the form of single testing monitor to examine indicators of condition level of U13 youth soccer players in one soccer team, with particular regard to speed. Methods: The research group consisted of 17 youth soccer players from SK Aritma Praha U13. We used single testing monitor, consisted from 5 different assessments: Acceleration speed test (10m sprint with 5m recorded time), Absolute locomotion speed test (20m sprint), Agility and speed test (505- agility test), Test for explosive power of lower limbs (vertical jump) and test for upper limbs explosive power (overhead two- handed throw with medicine ball). To evaluate data we used paired double sides (two-tails) T- test and confident interval of student dividing with 95% probability. Results: The result of our study showed significant decrease of speed with growing number of attempts in running tests, while in power tests mean rate remain constant or was increased with the next attempt. In general we could say that mean rate of two attempts of the same test was same as our predictions, althought in every test was almost one attempt significantly different....AtletikaFakulta tělesné výchovy a sportuFaculty of Physical Education and Spor
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