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Predicting the separation of time scales in a heteroclinic network

section we shall see why this simplification is useful. While in all of the following we work with eq. (3) , our results are still valid for the special case s i ≥ 0 ∀i , corresponding to eq. (1) after reversing the coordinate change. 3 Poincaré sections and return map Our goal is to construct a Poincaré map to determine the number of revolutions in an SHC before the trajectory turns to the heteroclinic connection of the LHC. We derive the return map by proceeding in the standard way, e.g. similarly to [ 19 ]. First, we determine local maps ϕ abc that

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Slurry shield tunneling in soft ground. Comparison between field data and 3D numerical simulation

simulation procedures, an experimental device was implemented. It is located in two different geological sites and consists of continuously measuring the displacements both on the surface and inside the massif, in order to identify the origin of the movements as well as to follow their evolution. The first site, which was intended to test the operating parameters of the TBM in a break-in area, consists of two sections (S1 and S2) with similar geologies but different geometries. They are located, respectively, at 30 and 65 m from the launching shaft, before crossing under

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Remarks On The Sources Of Error In The Modelling Of Lunar Geotechnical Structures

realized by the new 3D printing technology [ 11 ] , which could be the way for constructing the moon base. The described structure is founded on a natural regolith layer, which allows settlements of the same structure. The walls can translate and rotate and consequently active earth pressures in the soil can arise. In order to carry out the numerical simulations, the PLAXIS 3D FEM [ 12 ] code has been used. The setup for calculation has been characterized by a tolerated error of 0.01 and a maximum number of iterations equal to 60. To generate mesh ( Figure 2 ), a

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Construction and Monitoring of Cement/Bentonite Cutoff Walls: Case Study of Karkheh Dam, Iran

. Hence, to avoid this phenomenon, the following measures are recommended (based on experiences concluded from the construction of Karkheh Dam’s cut-off wall): Increasing the amount of bentonite consumed in plastic concrete Reducing the amount of water and cement Decreasing the diameter of the aggregates (decreasing the diameter of the largest aggregates of stone materials) Increasing the number of fine aggregates (aggregates passing through the No. 200 [75 μm ] sieve) Adding admixtures to concrete to increase shear strength and mortar specific gravity

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Geometric parameters optimization of planar interdigitated electrodes for bioimpedance spectroscopy

design parameters and frequency behavior in a coplanar impedance sensor is presented. The theoretical optimization of the geometrical parameters of the sensor is conducted by developing impedance equations and modeling equivalent circuits. One objective was to get the optimal ratio between the width of the electrodes and the gap between the electrodes to expand the useful frequency band, and the optimal number of electrodes. A sensor model including a priori the human blood medium was described with the finite element method FEM using CoventorWare® software for

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Development of a real-time, semi-capacitive impedance phlebography device

local maximum near n f s ≈ $\frac{n}{{{f}_{\text{s}}}}\approx $ 0.7s. Therefore, s f ( n ) was smoothed by a low-pass while the zero crossings of s df ( n ) were used to detect the maxima points. Due to the strong smoothing, there was a considerable time delay for the detection of a zero crossing, from positive to negative, in s df ( s ). Therefore, the algorithm detected only zero crossings, from negative to positive, in s df ( n ). After a zero-crossing was detected, s f ( n ) was maintained for the first value, which was smaller than the previous

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Extraction of cardiac and respiration signals in electrical impedance tomography based on independent component analysis

demands higher frame rates from the EIT instrument to capture the changes within a cardiac cycle. New generation EIT systems have overcome these demerits. The averaging over a large number of cardiac cycles requires long duration of data acquisition and therefore may not be suitable for continuous bedside or real-time monitoring. Furthermore, as Deibele et al [ 14 ] pointed out, this averaging over a large data set could result in the fact that ‘sudden changes or irregular anomalies cannot be detected’. In addition, with this method of acquisition, the ventilation

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Systematic variability in ICG recordings results in ICG complex subtypes – steps towards the enhancement of ICG characterization

ejection [ 5 ]. Additionally, to avoid interference in the baseline, the crossing point with the baseline of the dZ/dt signal (noted as the B point) [ 4 ] (opening of the aortic valve) was changed to a 15% response of the dZ/dt waveform from the baseline [ 5 ]. Fig. 1 Typical model of dZ/dt waveform recorded simultaneously with an ECG signal. Each signal is marked by characteristic points. Another group used the characteristic points of the dZ/dt signal as a simultaneous reference signal for phonocardiogram events [ 6 ], suggesting that dZ/dt can also provide

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Frequency dependent rectifier memristor bridge used as a programmable synaptic membrane voltage generator

memristance and correlates voltage and current. Thus, similar to a linear resistor its dimension is Ohm. x _ $\underset{\scriptscriptstyle-}{x}$ is a vector of the dimension n which is given by the number of internal state variables. The dynamics of this vector are specified by the equations (1) and (2) . HP memristor The HP memristor was realized in 2007 by a team of Hewlett Packard researchers led by Stanley Williams [ 8 , 9 ]. While this memristor is passive, the latest realization of a memristor is that of an active one on the base of niobium oxide [ 10

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