16 research outputs found
Cálculo da eficiência da simetria usando a relação de simetria da marcha, aplicando deformação dinâmica normalizada ao longo do tempo
In this paper we propose a new method for symmetry calculation in wearable devices. The problem in this domain is that only discrete features such as stride length, stride duration, or duration of gait phases are used for the symmetry calculation. However, this can lead to failures, since the use of features can result in partial loss of information from the time series. From this we present a possibility to calculate the symmetry by using Dynamic Time Warping (DTW). DTW uses the complete time series for the analysis and is therefore independent of certain features.En este artículo proponemos un nuevo método para el cálculo de la simetría para la resistencia sensible a la fuerza (FSR) en dispositivos portátiles. El problema en este dominio es que solo se utilizan características discretas como la longitud de la zancada, la duración de la zancada o la duración de las fases de la marcha para el cálculo de la simetría. Sin embargo, esto puede conducir a fallas, ya que el uso de funciones puede resultar en una pérdida parcial de información de la serie temporal. A partir de esto, presentamos la posibilidad de calcular la simetría utilizando el método de Dynamic Time Warping (DTW). El DTW utiliza la serie de tiempo completa para el análisis y, por lo tanto, es independiente de ciertas características.Neste artigo propomos um novo método para cálculo de simetria para resistência sensível à força (FSR) em dispositivos portáteis. O problema neste domínio é que apenas são utilizadas características discretas, como comprimento da passada, duração da passada ou duração da fase da marcha para o cálculo de simetria. No entanto, isso pode levar a falhas, pois o uso de funções pode resultar em perda parcial de informações da série temporal. A partir disso, apresentamos a possibilidade de calcular a simetria utilizando o método Dynamic Time Warping (DTW). O DTW usa toda a série temporal para a análise e, portanto, é independente de determinados recursos
Laser-induced electron diffraction of the ultrafast umbrella motion in ammonia
Visualizing molecular transformations in real-time requires a structural retrieval method with Ångström spatial and femtosecond temporal atomic resolution. Imaging of hydrogen-containing molecules additionally requires an imaging method that is sensitive to the atomic positions of hydrogen nuclei, with most methods possessing relatively low sensitivity to hydrogen scattering. Laser-induced electron diffraction (LIED) is a table top technique that can image ultrafast structural changes of gas-phase polyatomic molecules with sub-Ångström and femtosecond spatiotemporal resolution together with relatively high sensitivity to hydrogen scattering. Here, we image the umbrella motion of an isolated ammonia molecule (NH3) following its strong field ionization. Upon ionization of a neutral ammonia molecule, the ammonia cation (NH+3) undergoes an ultrafast geometrical transformation from a pyramidal (FHNH=107°) to planar (FHNH=120°) structure in approximately 8 femtoseconds. Using LIED, we retrieve a near-planar (FHNH=117±5°) field-dressed NH+3 molecular structure 7.8-9.8 femtoseconds after ionization. Our measured field-dressed NH+3 structure is in excellent agreement with our calculated equilibrium field dressed structure using quantum chemical ab initio calculations.J.B. and group acknowledge financial support from the European Research Council for ERC
Advanced Grant “TRANSFORMER” (788218), ERC Proof of Concept Grant “miniX”
(840010), FET-OPEN “PETACom” (829153), FET-OPEN “OPTOlogic” (899794), Laserlab-
Europe (EU-H2020 654148), MINECO for Plan Nacional FIS2017-89536-P; AGAUR for
2017 SGR 1639, MINECO for “Severo Ochoa” (SEV- 2015-0522), Fundació Cellex
Barcelona, CERCA Programme / Generalitat de Catalunya, and the Alexander von
Humboldt Foundation for the Friedrich Wilhelm Bessel Prize. J.B., K.A. and R.Moszynski.
acknowledge the Polish National Science Center within the project Symfonia,
2016/20/W/ST4/00314. J.B and B.B. acknowledge Severo Ochoa” (SEV- 2015-0522). J.B.
and A.S. acknowledge funding from the Marie Sklodowska-Curie grant agreement No.
641272. C.D.L is supported in part by Chemical Sciences, Geosciences and Biosciences
Division, Office of Basic Energy Sciences, Office of Science, U. S. Department of Energy
under Grant No. DE-FG02-86ER13491. J.S. and S.G. highly acknowledges support from
the European Research Council (ERC) for the ERC Consolidator Grant QUEM-CHEM
(772676). The authors thank Alejandro Saenz for helpful discussions.Peer ReviewedPostprint (author's final draft
Imaging the Renner-Teller effect using laser-induced electron diffraction
Structural information on electronically excited neutral molecules can be
indirectly retrieved, largely through pump-probe and rotational spectroscopy
measurements with the aid of calculations. Here, we demonstrate the direct
structural retrieval of neutral carbonyl disulfide (CS) in the BB
excited electronic state using laser-induced electron diffraction (LIED). We
unambiguously identify the ultrafast symmetric stretching and bending of the
field-dressed neutral CS molecule with combined picometer and attosecond
resolution using intrapulse pump-probe excitation and measurement. We invoke
the Renner-Teller effect to populate the BB excited state in neutral
CS, leading to bending and stretching of the molecule. Our results
demonstrate the sensitivity of LIED in retrieving the geometric structure of
CS, which is known to appear as a two-center scatterer
Binocular video head impulse test: Normative data study
IntroductionThe video head impulse test (vHIT) evaluates the vestibulo-ocular reflex (VOR). It’s usually recorded from only one eye. Newer vHIT devices allow a binocular quantification of the VOR.Purpose (Aim)To investigate the advantages of simultaneously recorded binocular vHIT (bvHIT) to detect the differences between the VOR gains of the adducting and the abducting eye, to define the most precise VOR measure, and to assess gaze dys/conjugacy. We aimed to establish normative values for bvHIT adducting/abducting eye VOR gains and to introduce the VOR dysconjugacy ratio (vorDR) between adducting and abducting eyes for bvHIT.MethodsWe enrolled 44 healthy adult participants in a cross-sectional, prospective study using a repeated-measures design to assess test–retest reliability. A binocular EyeSeeCam Sci 2 device was used to simultaneously record bvHIT from both eyes during impulsive head stimulation in the horizontal plane.ResultsPooled bvHIT retest gains of the adducting eye significantly exceeded those of the abducting eye (mean (SD): 1.08 (SD = 0.06), 0.95 (SD = 0.06), respectively). Both adduction and abduction gains showed similar variability, suggesting comparable precision and therefore equal suitability for VOR asymmetry assessment. The pooled vorDR here introduced to bvHIT was 1.13 (SD = 0.05). The test–retest repeatability coefficient was 0.06.ConclusionOur study provides normative values reflecting the conjugacy of eye movement responses to horizontal bvHIT in healthy participants. The results were similar to a previous study using the gold-standard scleral search coil, which also reported greater VOR gains in the adducting than in the abducting eye. In analogy to the analysis of saccade conjugacy, we propose the use of a novel bvHIT dysconjugacy ratio to assess dys/conjugacy of VOR-induced eye movements. In addition, to accurately assess VOR asymmetry, and to avoid directional gain preponderance between adduction and abduction VOR-induced eye movements leading to monocular vHIT bias, we recommend using a binocular ductional VOR asymmetry index that compares the VOR gains of only the abduction or only the adduction movements of both eyes
Imaging an isolated water molecule with an attosecond electron wave packet
We use laser-induced electron diffraction (LIED) to self-image the molecular structure of an isolated water molecular ion using its own retuning attosecond electron wave packet (EWP). Using LIED’s sub-femtosecond and picometre spatio-temporal resolution imaging capabilities, we observe the symmetric stretching of the O-H and H-H internuclear distances with increasing laser field strength.Postprint (published version
Ultrafast imaging of the Renner-Teller effect in a field-dressed molecule
We present experimental results of linear-to-bent transition of field-dressed molecules, mediated by Renner-Teller effect. Using the state-of-the-art laser-induced electron diffraction (LIED) technique, we image a bent and symmetrically stretched carbon disulfide (CS2) molecule populating an excited electronic state under the influence of strong laser field. Our findings are well-supported by ab initio quantum mechanical calculations.Peer ReviewedPostprint (published version
Analysis and Classification of Motor Dysfunctions in Arm Swing in Parkinson’s Disease
Due to increasing life expectancy, the number of age-related diseases with motor dysfunctions (MD) such as Parkinson’s disease (PD) is also increasing. The assessment of MD is visual and therefore subjective. For this reason, many researchers are working on an objective evaluation. Most of the research on gait analysis deals with the analysis of leg movement. The analysis of arm movement is also important for the assessment of gait disorders. This work deals with the analysis of the arm swing by using wearable inertial sensors. A total of 250 records of 39 different subjects were used for this task. Fifteen subjects of this group had motor dysfunctions (MD). The subjects had to perform the standardized Timed Up and Go (TUG) test to ensure that the recordings were comparable. The data were classified by using the wavelet transformation, a convolutional neural network (CNN), and weight voting. During the classification, single signals, as well as signal combinations were observed. We were able to detect MD with an accuracy of 93.4% by using the wavelet transformation and a three-layer CNN architecture
За кадры. 1977. № 37 (2032)
Добро пожаловать на электроэнергетический факультет! / Н. Г. ВолковПриумножая традиции / Н. БанныхЭлектрические станции / И. Д. КутявинКибернетика электрических систем / Р. А. ВайнштейнЭлектрические системы / Н. БанныхТехника высоких напряжений / В. Я. УшаковЭлектроснабжение промышленных предприятий / М. А. МельниковМы - целине, целина - нам / Т. КуммерЗаботы профбюро / С. БалакинСильные, ловкие, смелые / Л. АзаренковаУсловия прием
Far Away and Yet Nearby - A Framework for Practical Distance Fraud on Proximity Services for Mobile Devices (Demo)
Gesture recognition with 3D sensors using Hidden Markov Models and clustering
We propose a method for recognizing dynamic gestures using a 3D sensor. New aspects of the developed system include problem-adapted data conversion and compression as well as automatic detection of different variants of the same gesture via clustering with a suitable metric inspired by Jaccard metric. The combination of Hidden Markov Models and clustering leads to robust detection of different executions based on a small set of training data. We achieved an increase of 5% recognition rate compared to regular Hidden Markov Models. The system has been used for human-machine interaction and might serve as an assistive system in physiotherapy and neurological or orthopedic diagnosis