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Oscillation response

All the information about the response of the sample at this frequency [Pg.107]

In order to describe the material properties as a function of frequency for a body that behaves as a Maxwell model we need to use the constitutive equation. This is given in Equation (4.8), which describes the relationship between the stress and the strain. It is most convenient to express the applied sinusoidal wave in the exponential form of complex number notation  [Pg.108]

Now the stress response is shifted through a phase angle 5  [Pg.108]

So if we substitute the complex stress and strains into the constitutive equation for a Maxwell fluid the resulting relationship is given by Equation (4.21)  [Pg.109]

The ratio of the stress to the strain is the complex modulus G (a ). We can rearrange this expression to give the complex modulus and the frequency, and using Equation (4.14) we have  [Pg.109]


Figure 11 shows typical CL oscillating responses of this system as perturbed by vitamin B6 pulses, which decrease the oscillation amplitude. Arrowheads indicate the times at which analyte pulses were introduced. Zone A corresponds to the oscillating steady state zone B to the response of the oscillating system to vitamin B6 perturbations and zone C to the recovery following each perturbation (second response cycle), which was the measured parameter. This... [Pg.198]

K. Tomheim, Are metabolic oscillations responsible for normal oscillatory insulin secretion Diabetes 46, 1375-1380 (1997). [Pg.288]

The response has a high maximum deviation and there is a significant time of oscillation (response time). The period of this oscillation is moderate. For a sustained change in load, the controlled variable is not returned to its original value (the desired value) but attains a new equilibrium value termed the control point. This difference between the desired value and the control point is called the offset or droop. The reason for offset with proportional action can be seen if it is remembered that the control action is proportional to the error. [Pg.566]

R-band are mostly connected with motions of oxygen atoms, which actually determine the harmonic-oscillator response. Hence, these facts would be difficult to interpret if we didn t accept the viewpoint that cooperative effects should be superimposed on the motions of a water molecule as a whole. [Pg.239]

General Second-Order Element Figure 8-3 illustrates the fact that closed-loop systems can exhibit oscillatory behavior. A general second-order transfer function that can exhibit oscillatory behavior is important for the study of automatic control systems. Such a transfer function is given in Fig. 8-15. For a unit step input, the transient responses shown in Fig. 8-16 result. As can be seen, when t, < 1, the response oscillates and when t, < 1, the response is S-shaped. Few open-loop chemical processes exhibit an oscillating response most exhibit an S-shaped step response. [Pg.9]

A sufficient condition is lim oo i/ — ihy)B(t) = (A)(B (= 0 since A and B are centered).4 In systems with a finite number of degrees of freedom, and thus with oscillating response and correlation functions, this limit does not even exist. Nevertheless, Eqs. (40) and (41) still apply, provided we introduce a small damping which will be eventually let equal to zero, or, which amounts to the same, we treat the response and correlation functions as distributions. [Pg.272]

This relationship was recently questioned by Li et al. 40,116) when they reported the observation of bands at 490, 530 and 1125 cm in the UV-excited (244 nm) Raman spectra of TS-1. Bands at 1085 and 1110 cm were also observed for Ti-Si02 prepared by chemical grafting 117) and for Ti-MCM-41 118), respectively. Raman bands near 1120 cm in addition to the 960 cm band had been reported earlier for TS-1 by Scarano et al. 113) and Deo et al. 119), who used conventional Raman spectroscopy (NIR excitation), and later by Bordiga et al. 39), who used UV-visible- and NIR-excitation. Li et al. 40,116) were the first to show that the bands of TS-1 at 490, 530, and 1125 cm and the corresponding bands of Ti-MCM-41 were resonance-enhanced when the Raman spectra were excited in the UV (244 nm) in the wavelength region of the 0 Ti + ( whereas the 960 cm this observation, the authors concluded that the oscillator responsible for the 960 cm band cannot be located in the immediate vicinity of the Ti atom. Consequently, they also proposed that the three resonance-enhanced bands at... [Pg.41]

The upper curve was calculated by the method of characteristics program and it exhibits a true limit cycle or sustained oscillation response (19). The middle curve was calculated by the distance method of lines program. The response is attenuated and stretched out. The final long term oscillations had random unequal periods and they were out of phase with the MOC results. The lower curve was calculated by the time method of lines program. The initial part of the response is similar to the DMOL results but then the temperature incorrectly levels out to a steady state condition. Thus, it was evident that the distance and time method of lines techniques were not as accurate as the method of characteristics procedure for calculating the gasifier step responses and they were discarded. [Pg.345]

Stenchikov G., Robock A., Ramaswamy V., Schwarzkopf M. D., Hamilton K., and Ramachandran S. (2002) Arctic Oscillation response to the 1991 Mount Knambo eruption effects of volcanic aerosols and ozone depletion. J. Geophys. Res. Doi 10.1029/2002JD002090 (28 December 2002). [Pg.1429]

Conservation of momentum is also found in the oscillator responses from molecules but here the simultaneous conservation of energy as well... [Pg.206]

The parameters of the oscillating response are basically related to the features of the key volatile compound while the presence of other compounds instead of the key one will significantly change the appearance of the oscillations. The detection time might be reduced to the duration of the two initial periods of the oscillating response without a loss of the information about the gas mixture. [Pg.178]

The increase in the speed of system s response and the decrease in the offset, both very desirable features, come at the expense of higher overshoots (maximum errors) and longer oscillating responses. Thus, as Kc increases, causing to decrease ... [Pg.146]

On the contrary, if Kc < 8.56, then AR < 1 when = -180°. Consequently, the oscillating response of the closed loop of Figure 18.3b will exhibit a continuously decreasing amplitude, leading to an eventual dying out of the oscillation. [Pg.183]

How would you select the sampling rate for (a) the response of a general underdamped open-loop system, and (b) the oscillating response of a closed-loop system ... [Pg.660]

In fact, the electronic control system of the fuel feed, which is back-fed from the . oxygen sensor, shows a quick oscillating response to A/F fluctuations with a frequency of about 1-4 Hz. [Pg.169]

From changes of the surface pressure n with time the elasticity can be obtained, while the phase shift between the generation of area oscillations and the pressure oscillation response is a measure of the exchange of matter [introduced by Lucassen as dilational viscosity, cf. (180)]. [Pg.28]

Suppose now that we work in a particular fixed value B of the magnetic field (different from for which the two levels of interest have the values and separated by the small interval E2 -(see Fig. 5). Each successive incoherent pulse produces a decaying and oscillating response Sj (t) analogous to the one of Fig. 4. We represent on Fig. 6 these successive responses S], S2, S3,. .., which have the same frequency 0012 but random phases. At a particular time t, the whole fluorescence intensity l(B,t) is obtained by summation of the intensities Si(t), S2(t), S3(t) emitted by different atoms, which have been... [Pg.159]

Since the jp-polarized radiation at cpi 0° has tangential and normal electric field components (1.4.4°), these components will interact with those dipoles within the film that are oriented parallel and perpendicnlar to the snrface, respectively, according to the selection mle (1.27). Fmthermore, under action of the external electric field normal to the surface, the dipoles experience an additional electric field induced by the polarized chemical bonds within the layer. It follows that in the jp-polarized spectra, the band near the longitudinal optical mode vlo will be observed, in addition to the band near vro resulting from the dipoles parallel to the film. In light of the discussion in Section 1.8.2, it is evident that because the dipole oscillations responsible for the vro band are directed along the surface, these oscillations will be quenched by a metal surface and, hence, be absent in p-polarized spectra of films on mefal substrates, as demonstrated in Fig. 3.2. [Pg.146]

McGuire, R. K. Seismic Design Spectra and Mapping Procedures Using Risk Analysis Based Directly on Oscillator Response. Branch of Seismicity and Risk Analysis, USGS, Denver, CO, 1975. [Pg.126]

Fig. 2.9 A monochromatic light beam passing through the Fourier transform spectrometer creates an oscillating response on the detector (a). The signal fiom polychromatic light creates an interferogram (b), which can be deconvoluted by a Fourier transform to recover the frequency domain spectrum. The frequencies forming the interferogram will be represented by peaks whose amplitude is proportional to the intensity of the the light of that frequency impinging on the detector (c)... Fig. 2.9 A monochromatic light beam passing through the Fourier transform spectrometer creates an oscillating response on the detector (a). The signal fiom polychromatic light creates an interferogram (b), which can be deconvoluted by a Fourier transform to recover the frequency domain spectrum. The frequencies forming the interferogram will be represented by peaks whose amplitude is proportional to the intensity of the the light of that frequency impinging on the detector (c)...

See other pages where Oscillation response is mentioned: [Pg.723]    [Pg.95]    [Pg.198]    [Pg.41]    [Pg.107]    [Pg.238]    [Pg.396]    [Pg.198]    [Pg.527]    [Pg.53]    [Pg.547]    [Pg.364]    [Pg.109]    [Pg.176]    [Pg.178]    [Pg.521]    [Pg.653]    [Pg.68]    [Pg.727]    [Pg.160]    [Pg.161]    [Pg.306]    [Pg.276]    [Pg.64]    [Pg.247]   
See also in sourсe #XX -- [ Pg.107 ]




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