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Abstract

Dynamic testing of bridges has as target to establish their response on pulse forces between the wheels and unevenness of road surface. Generally, during the tests, real time accelerations or deformations are to be measured and which through successive processing methods lead to other data as velocities, displacements, dynamic impact factor, but also the damping ratio. In order to validate the bridge response following testing, the measured data are compared both with allowable limits existing in standards and with the results obtained using analytical or numerical models.

In Romania, the dynamic testing of bridges is recommended by the current standards, only for important bridges, erected in complex or special solutions and also for large span bridges.

The aim of this paper is to outline the results obtained from the on-site measurements during dynamic testing of a viaduct placed on the motorway A1, sector Orăştie-Sibiu. The bridge superstructure is a composite one, continuous girder on 12 spans: 40+10×60+40 m, the substructure consisting in 11 piers with lamellar elevations and variable height in the range 8.50-24m.

In the paper a finite element model is also presented which was used for time-history analyses using an impulse type load. Finally, the results obtained on the site and using the numerical model are compared and discussed.

Abstract

In this paper a functional model to estimate the inelastic displacement ratio as a function of the ductility factor is presented. The coefficients of the functional model are approximated using nonlinear regression. The used data is in the form of computed displacement for an inelastic single degree of freedom system with a fixed ductility factor. The inelastic seismic response spectra of constant ductility factors are used for generating data. A method for selecting ground-motions that have similar frequency content to that of the ones picked for the comparison is presented. The variability of the seismic response of nonlinear single degree of freedom systems with different hysteretic behavior is presented.

Non-Intrusive Device for Real-Time Circulatory System Assessment with Advanced Signal Processing Capabilities

This paper presents a device that uses three cardiography signals to characterize several important parameters of a subject's circulatory system. Using electrocardiogram, finger photoplethysmogram, and ballistocardiogram, three heart rate estimates are acquired from beat-to-beat time interval extraction. Furthermore, pre-ejection period, pulse transit time (PTT), and pulse arrival time (PAT) are computed, and their long-term evolution is analyzed. The system estimates heart rate variability (HRV) and blood pressure variability (BPV) from the heart rate and PAT time series, to infer the activity of the cardiac autonomic system. The software component of the device evaluates the frequency content of HRV and BPV, and also their fractal dimension and entropy, thus providing a detailed analysis of the time series' regularity and complexity evolution, to allow personalized subject evaluation.

G, Georgoulis A. Frequency content asymmetry of the isokinetic curve between ACL deficient and healthy knee. J Biomech, 2004; 37: 857-864 Weerdesteyn V, Nienhuis B, Duysens J. Advancing age progressively affects obstacle avoidance skills in the elderly. Hum Mov Sci, 2005; 24: 865-80 Zampeli F, Moraiti CO, Xergia S, Tsiaras VA, Stergiou N, Georgoulis AD. Stride-to-stride variability is altered during backward walking in anterior cruciate ligament deficient patients. Clin Biomech, 2010; 25: 10371041

. Journal of the Royal Statistical Society: Series A (Statistics in Society), 2008; 171: 5-19 Suter E, Herzog W. Extent of muscle inhibition as a function of knee angle. Journal of electromyography and kinesiology : official journal of the International Society of Electrophysiological Kinesiology, 1997; 7: 123-130 Tsepis E, Giakas G, Vagenas G, Georgoulis A. Frequency content asymmetry of the isokinetic curve between ACL deficient and healthy knee. Journal of biomechanics, 2004; 37: 857-864 Welsch MA, Williams PA, Pollock ML, Graves JE, Foster DN, Fulton MN

[11] Z. M. Hussain, A. Z. Sadik, and P. O'Shea, Digital Signal Processing . Berlin: Springer, 2011, p. 15. [12] Q. Q. Ni, “Wavelet transform of acoustic emission signals in failure of model composites,” Engineering Fracture Mechanics , vol. 69, no. 6, pp. 717–728, 2002. https://doi.org/10.1016/S0013-7944(01)00105-9 [13] C. R. Ramirez-Jimenez, N. Papadakis, N. Reynolds, T. H. Gan, P. Purnell, and M. Pharaoh, “Identification of failure modes in glass/polypropylene composites by means of the primary frequency content of the acoustic emission event,” Composites

1 Introduction Inward burning engines are regularly prepared for and debilitate suppressor on smother those acoustic pulse created toward those ignition methodology. A high intensity pressure wave produced toward burning in the motor barrel propagates along the fumes channel and radiates from the fumes channel end. Those pulse repeats toward those terminating recurrence of the motor which may be characterized by f = (engine rpm x number from claiming cylinders)/120 to a four stroke motor. The frequency content of exhaust noise may be commanded by an pulse in the

frequencies, which is introduced in [ 27 ]. However, in the case of pulmonary oedema, the effect of this delay will be suppressed by averaging and does not require additional attention. The scope of this paper relates only to the relationship between the frequency content of an interfering signal and the impedance sampling rate and compromises within this context. The design of a system for acquisition of impedance spectra involves greater number of degrees of freedom, such as choice of estimation method, e.g. swept sine, multi sine, or other, and the number of frequencies

necessary to interpose a transmission (gear) to optimize the transfer of mechanical power from the motor to the joint. During this transfer, the power is dissipated as a result of friction. The use of gearing is a well-established means for accomplishing such an objective because it is possible to use smaller actuators to deliver larger torques [ 7 ]. However, one of the biggest disadvantages of the addition of gearing is the presence of backlash that reduces the effective bandwidth of the controller since high frequency content in the control produces noisy and

. Rewards also come from the audience. Table 2 Frequency, content (number of articles per subject) and ads Site and company Time span 20 updates Local politics Crime and accidents Local events Local business Local culture Local sports Lifestyle (food, interior design) Not local Other Visible ads on landing page Comments NyheterSTO 3 days 1 12 1 1 1 1 0 0 3 18 13 partners, plus 6 advertisers, but also several links to other sites Bättre stadsdel 5 days 7 7 4 1 0 0 0 0 1 10 Märsta.nu 4 days 1 6 2 2 0 8 0 0 1 20 Frilagt.se 16 days 15 2 0 0 0 1 0 0 2 1 Measured in January