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Periodic extension

PERIODIC EXTENSIVE SMALL BUBBLE FORMATION, A STEADY CIRCULATION, 21... [Pg.491]

We used molecular combing to determine Young s modulus for individual microfibrils, and X-ray diffraction of zonular filaments of the eye to establish the linearity of microfibril periodic extension (Sherratt et al, 2003). Microfibril periodicity is not altered at physiological zonular tissue extensions, and Young s modulus is between 78 to 96 MPa, MPa, which is two orders of magnitude stiffer than elastin. Thus, elasticity... [Pg.419]

The dynamic methods depend on the fact that certain vibrations of a liquid cause periodic extensions and contractions of its surface, which are resisted or assisted by the surface tension. Surface tension therefore forms an important part, or the whole, of the restoring force which is concerned in these vibrations, and may be calculated from observations of their periodicity. Dynamic methods include determination of the wave-length of ripples, of the oscillations of jets issuing from non-circular orifices, and of the oscillations of hanging drops. Dynamic methods may measure a different quantity from the static methods, in the case of solutions, as the surface is constantly being renewed in some of these methods, and may not be old enough for adsorption to have reached equilibrium. In the formation of ripples there is so little interchange of material between the surface and interior, and so little renewal of the surface, that the surface tension measured is the static tension ( 12. ... [Pg.363]

Also of importance to note with the PVDF method, we observed Triton to contaminate the HPLC system, most notably the flow cell, after multiple injections. In several instances, this was serious enough to produce many high UV-absorbing peaks and prevented collection of the in-progress map. Periodic, extensive washing of the system may help resolve this. [Pg.158]

For a periodic boundary, all electric and magnetic fields are calculated via periodic extensions. [Pg.148]

As stated previously, with most applications in analytical chemistry and chemometrics, the data we wish to transform are not continuous and infinite in size but discrete and finite. We cannot simply discretise the continuous wavelet transform equations to provide us with the lattice decomposition and reconstruction equations. Furthermore it is not possible to define a MRA for discrete data. One approach taken is similar to that of the continuous Fourier transform and its associated discrete Fourier series and discrete Fourier transform. That is, we can define a discrete wavelet series by using the fact that discrete data can be viewed as a sequence of weights of a set of continuous scaling functions. This can then be extended to defining a discrete wavelet transform (over a finite interval) by equating it to one period of the data length and generating a discrete wavelet series by its infinite periodic extension. This can be conveniently done in a matrix framework. [Pg.95]

Another difficulty that arises with data sets is the non-standard size or length. That is, the DFT assumes a data size equal to a power of 2 which is not normally the size of spectra or other similar discrete data. When the data set size is a power of 2 (such as in an image), periodic extension with the DFT inherently handles such a situation. However, with non-standard sizes, some form of extension up to a power of 2 is usually performed, thereby allowing the application of the periodised DFT. This we also investigate in the context of the boundary extension techniques. [Pg.99]

A multi-resolution analysis for L"([0, K]) can be built with the sequence of sub-spaces being of finite dimension equal to 2 K and the top-level subspace representing the coarsest resolution. An alternative way of viewing the periodic extension of data is to periodically wrap the transform matrix. [Pg.99]

The major advantage of periodic extension is that no additional coefficients are required (if the number of data points is a power of 2) and it preserves the orthogonality of the DWT. However, if singular end-effects owing to nonperiodicity is a major concern, then consideration should be given to using other extension techniques, such as symmetric extension. [Pg.111]

Symmetric extension has the advantage, compared with periodic extension, that the function at the interval boundaries is continuous. However, the first... [Pg.111]

Fig. 16 shows the effect of symmetric boundary extension on the WPT (only the scaling coefficients at the first level of decomposition are shown) of the NMR spectrum of lohophytum contpactum coral (Fig. 4). The singularity generated by applying periodic extension (see Fig. 11) has been eliminated through the use of symmetric boundary extension. Fig. 16 shows the effect of symmetric boundary extension on the WPT (only the scaling coefficients at the first level of decomposition are shown) of the NMR spectrum of lohophytum contpactum coral (Fig. 4). The singularity generated by applying periodic extension (see Fig. 11) has been eliminated through the use of symmetric boundary extension.
As in the case of symmetric extension, the data will need to be padded (at both ends of the sequence) to 2- data points prior to applying periodic extension. Fig. 17 shows the resulting WPT for a ramp signal when zeropadding boundary extension has been applied. ... [Pg.114]

In what follows (unless otherwise stated), we study only those periodic solutions (determined by initial vector functions) which are periodic extensions of periodic solutions onto initial sets. [Pg.5]

Due to the thermal inertia of the system, the minimum time for the solidification is about 15-20 min. During this period, extensive changes of blends morphology may take place. The observed structure can hardly reflect the structure existing during the blending... [Pg.949]

In practice, one frequently encounters problems in which a function is defined on the interval [—tt, tt]. In these cases, a periodic extension as shown in Figure 5.2 can be made, and those functions can be represented by the Fourier series expansion even though one is only interested in the expansion on [—tt, tt]. [Pg.162]

We need the odd periodic extension of/(x) shown in Figure 5.6, which follows. [Pg.165]

What methods can measure Text In practice, the most convenient approach has been to study situations of relatively strong shear (s t 1), choosing transverse shears to ensure that the molecule rotates and experiences a periodic extension/contraction cycle. - The main parameters measured were nonlinear features in the viscosity and in the flow birefringence— the latter being slightly simpler to interpret. All these nonlinear corrections finally determine the product SText- The measurements... [Pg.199]

Secondly, if an application implying self-adhesive LR requires reliable bonding over the whole service period, extensive testing will be necessary prior to its use. [Pg.299]

Windows are weighting functions applied to data to reduce the order of the discontinuity at the boundary of the periodic extension. Harris [71] has given a comprehensive review of the properties of over 30 windowing functions and we illustrate their properties with reference to a Blackman window, W. ... [Pg.538]

In the same period, extensive investigations of lyotropic liquid crystalline phases, including cubic mesophases, were started by several groups. This fascinating subject has been developed into a separate field and will be covered in Vol. 3 of this handbook. However, some candidates exhibit cubic phases in the water-free state, these will be mentioned in this chapter. Luzzati and Spegt [5] and Spegt and Skoulios [6] have published investigations of strontium alka-noates which form (likewise) thermotropic... [Pg.1900]


See other pages where Periodic extension is mentioned: [Pg.491]    [Pg.177]    [Pg.505]    [Pg.167]    [Pg.174]    [Pg.333]    [Pg.10]    [Pg.135]    [Pg.79]    [Pg.595]    [Pg.99]    [Pg.104]    [Pg.109]    [Pg.112]    [Pg.117]    [Pg.118]    [Pg.465]    [Pg.838]    [Pg.31]    [Pg.162]    [Pg.167]    [Pg.887]    [Pg.63]    [Pg.64]   
See also in sourсe #XX -- [ Pg.3 , Pg.3 , Pg.292 ]

See also in sourсe #XX -- [ Pg.111 ]




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