The Italica Project is the implementation of an Electronic Health Record system at the Italian Hospital of Buenos Aires. The present work shows the implementation of a Medical Signal Grid Repository module and its int...
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In this paper a cumulant-based method for identification of gait using accelerometer data is presented. Acceleration data of three different walking speeds (slow, normal and fast) for each subject was acquired by the ...
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In this paper a cumulant-based method for identification of gait using accelerometer data is presented. Acceleration data of three different walking speeds (slow, normal and fast) for each subject was acquired by the accelerometer embedded in cell phone which was attached to the person's hip. Data analysis was based on gait cycles that were detected first. Cumulants of order from 1 to 4 with different number of lags were calculated. Feature vectors for classification were built using dimension reduction on calculated cumulants by principal component analysis (PCA). The classification was accomplished by support vector machines (SVM) with radial basis kernel. According to portion of variance covered in the calculated principal components, different lengths of feature vectors were tested. Six healthy young subjects participated in the experiment. The average person recognition rate based on gait classification was 90.3±3.2%. A similarity measure for discerning different walking types of the same subject was also introduced using dimension reduction on accelerometer data by PCA.
A generalization of the modified Cagniard method (‘Cagniard‐DeHoop method’) is used to obtain closed‐form analytic time‐domain expressions for the line‐source excited pulsed acoustic wave pressure associated wit...
A generalization of the modified Cagniard method (‘Cagniard‐DeHoop method’) is used to obtain closed‐form analytic time‐domain expressions for the line‐source excited pulsed acoustic wave pressure associated with the reflection against the mass‐loaded planar boundary of a semi‐infinite fluid. The expressions reveal the generation of anomalous waveforms near the boundary at large offsets from the source. Their occurrence can be interpreted as a surface effect. As the analysis shows, they are, however, not surface waves in the strict sense of the definition.
Experimental skin reflectance measurement setup is presented to acquire skin color signals under different illuminant conditions directly by an image sensor. To obtain stimulus of varying illuminant conditions an adju...
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Experimental skin reflectance measurement setup is presented to acquire skin color signals under different illuminant conditions directly by an image sensor. To obtain stimulus of varying illuminant conditions an adjustable RGB light source is used. Skin color modeling is an important step for efficient skin color image segmentation, which plays an important role when defining regions of interest in image sequence for a successful hand tracking and gesture recognition within spatially defined vision based interaction. To improve detection accuracy of pixel based skin color segmentation a parametric skin color model can be used, which is able to adapt different illuminant conditions. Therefore skin reflectance under different illuminants plays an important role to obtain such a model. Experimental results of hand skin reflectance measurements within chromaticity space are shown.
In this paper we present an extended Krylov method to simulate the transient response of multiconductor transmission lines. The extended Krylov space is generated by the transmission line system matrix and its inverse...
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In this paper we present an extended Krylov method to simulate the transient response of multiconductor transmission lines. The extended Krylov space is generated by the transmission line system matrix and its inverse. Loosely speaking, the idea is that early-times are approximated by powers of the system matrix, while late-times are approximated by powers of its inverse. Acting with the system matrix or its inverse on a given vector is an O(p) process, where p is the order of the total system. Moreover, both matrices are so-called J-symmetric matrices and we show that it is possible to generate a J-orthogonal basis of the extended Krylov space via short Lanczos/CG-type recurrence relations.
The superconducting SmFeAsO1−xFx (x=0.2) polycrystalline bulks were prepared by the powder-in-tube (PIT) method. The magnetic field and temperature dependences of critical current densities in the samples were investi...
The superconducting SmFeAsO1−xFx (x=0.2) polycrystalline bulks were prepared by the powder-in-tube (PIT) method. The magnetic field and temperature dependences of critical current densities in the samples were investigated by resistive and ac inductive (Campbell's) methods. It was found that a fairly large shielding current density over 109 A/m2, which is considered to correspond to the local critical current density, flows locally with the perimeter size similar to the average grain size of the bulk samples, while an extremely low transport current density of about 105 A/m2 corresponding to the global critical current density flows through the whole sample. Furthermore, a unique history dependence of global critical current density was observed, i.e., it shows a smaller value in the increasing-field process than that in the decreasing-field process. The history dependence of global critical current characteristic in our case can be ascribed to the existence of the weak-link property between the grains in SmFeAsO1−xFx bulk.
The IEEE WLAN 802.11a/g standard requires short time interval (5.6 mus) for automatic gain control (AGC) convergence during reception of the preamble in each data packet. Due to this stringent settling time requiremen...
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The IEEE WLAN 802.11a/g standard requires short time interval (5.6 mus) for automatic gain control (AGC) convergence during reception of the preamble in each data packet. Due to this stringent settling time requirement, most of the AGC is implemented after the baseband filter, which leads to high power consumption in the baseband filter. In this paper, we present syllabic companding using switched capacitor (SC) ciruits as a solution to achieve gain control in the baseband filter without sacrificing any of the AGC settling time. A 5 th order syllabic companding, Chebyshev type, SC filter with a cut-off frequency of 10 MHz is implemented in IBM's 1.2 V, 130 nm CMOS technology. The filter consumes a total power of 45 mW. It is estimated that companding by a factor of 4 achieves 12 dB improvement in dynamic range and a reduction in power consumption by a factor of 4.3 with respect to conventional filters.
The coupling between a dielectric waveguide and a photonic crystal waveguide is studied theoretically and experimentally. The coupling methods studied in this work include graded photonic crystal coupler, photonic cry...
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Flame Spray Synthesis, FSS, was used to grow TiO2-based nanopowders from which TiO2:Cr nanosensors were obtained. Structural properties of crystalline TiO2:Cr nanopowders at different Cr loadings (0.1-5.0 at. % Cr) ha...
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ISBN:
(纸本)9781617823848
Flame Spray Synthesis, FSS, was used to grow TiO2-based nanopowders from which TiO2:Cr nanosensors were obtained. Structural properties of crystalline TiO2:Cr nanopowders at different Cr loadings (0.1-5.0 at. % Cr) have been investigated. Material studies have been performed using standard methods: X-ray Diffraction, XRD, Transmission Electron Microscopy, TEM, and Brunauer-Emmett- Teller, BET, adsorption isotherms. High specific surface area SSA (37-126 m2/g) and small crystallite size (9-27 nm) have been reached. Incorporation of Cr into TiO2 lattice affects the specific surface area of nanopowders, crystallite size and rutile - to anatase ratio. Gas sensing characteristics of TiO2:Cr nanosensors upon interaction with H2 have been recorded in the self - assembled experimental system. The detection of hydrogen was carried out over the concentration range of 50-3000 ppm at the temperatures extending from 200 to 400oC. It is demonstrated that nanomaterials based on TiO2:Cr are attractive for ultimate sensors applications due to a decrease in the operating temperature down to 210-250oC, accompanied by an increase in the sensor response. Taking into account the possible operating costs the best candidates for the commercial use are TiO2: 1 at. % Cr and TiO2: 5 at. % Cr nanosensors.
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