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Point space

Equation (4-210) is known as the sampling theorem. It states that any time function limited to a frequency W can be uniquely determined by its values at sample points spaced 1/2W apart. Thus if both the input and output from a channel are limited to a frequency W, then we can represent the input and output as sequences of real numbers spaced at intervals of 1/2 W. If each output in this sequence depends on only one input, then the results for continuous input, continuous output channels can be applied. One particularly important case in which ... [Pg.245]

A well point system consists of several individual well points spaced at 0.6 m to 1.8 m intervals along a specified alignment. A well point is a well screen (length 0.5 to 1.0 m) with a conical steel drive point at bottom. Individual well points are attached to a riser pipe (diameter 2.5 to 7.5 cm) and connected to a header pipe (diameter 15 to 20 cm). At the midpoint, the header pipe is connected to a centrifugal pump. As yield at different well points may vary, a valve at the top of each riser pipe is used to control the drawdown so that the screen bottom is exposed. The pump provides 6 to 7.5 m of suction, but friction losses reduce the effective suction to 4.5 to 5.4 m. [Pg.621]

The method we have used until now for estimating the derivative, simply calculating the difference between absorbance values of two data points spaced some distance apart (and dividing by that AX, of course), is probably the simplest method available. As we discussed in out previous chapter [4], however, there is a disadvantage associated with... [Pg.360]

The nature of the convolution function matters, however, and so do the details of the way it is computed. To see this, let us begin by considering the two-point derivative we have been dealing with in most of this sub-series of chapters. For our first examination of the effect, let us consider that we are computing the derivative from adjacent data points spaced 1 nm apart (such as in our initial discussion of derivatives [1]). [Pg.373]

Test Procedures. Coatings were tested by the following procedures. For crosshatch adhesion, ASTM-D3359, a special scribe was employed which had 11 sharp points spaced approximately 1 mm apart. The film was scored twice with this tool so that scratches were perpendicular. Special tape was then placed firmly over the scored area and pulled off. The number of squares of film coating remaining were counted, and this provided a numerical basis for measuring surface adhesion. No squares are removed for a satisfactory coating. [Pg.221]

If the fluid enters the vessel at one central point, as indicated in Figure 23.3, rather than at many points spaced across a circular distributor, as in Figure 23.1, the action is different as us increases a spouted bed results rather than a fluidized bed. A spouted bed is characterized by a high-velocity spout of gas moving up the center of the bed, carrying particles to the top. This action induces particle circulation, with particle motion toward the wall and downward around the spout and toward the center. The particles in a spouted bed are relatively large and uniformly sized. [Pg.571]

Calculation of well-point spacing and expected pumping rate is usually based on procedures using the Dupuit (steady-state) equation, as described in standard tests. The following factors must be considered in addition to standard water pumping considerations ... [Pg.218]

Horticulture Pit. Core samples of soil of about 100 g size to a depth of 10 cm and liquid samples of 500 mL were taken from eight sampling points spaced uniformly across the pit surface. Each sample was then solvent extracted individually and the pesticides and degradation products were separated and quantitated. [Pg.72]

A fill stop (period), not a comma, is used for the decimal point. Spaces, not commas, are used for thousands (not the case for the house style of this book, unfortunately). [Pg.307]

A related issue is that the potential can be very sensitive to grid points very near the cavity surface, where die dielectric constant is changing instantaneously. By construction, die cavity is actually defined only to within the grid-point spacing. The van der Waals radii defining the cavity surface that determines whedier a given gridpoint is inside or outside the solute may either be chosen arbitrarily or optimized for a particular computational model (see, for example, Banavali and Roux 2002). [Pg.399]

The cracking reaction in all catalytic cracking processes is affected by the following factors (2) catalyst type and inherent activity charge stock characteristics and midboiling point space rate, usually measured in terms of liquid oil volume per volume of catalyst per hour ratio of catalyst to oil, the amount of catalyst in the reaction zone per unit of oil reacted, which in the fixed-bed process becomes the ratio of reciprocal space rate to time on stream, and in the moving-bed process is the ratio of catalyst rate to oil rate temperature and oil partial pressure. [Pg.16]

Plane-wave GGA density-functional calculations [58] and similar computational conditions as used in the study by Koudriachova et al. [136], in the present work a kinetic energy cutoff of 380 eV and a k-point spacing of 0.06 A-1. c From ref. [137], where a modification of the 6-31G basis set was used. d For studies of pure anatase employing local density approximation (LDA) DFT calculations, see e.g. ref. [138]. [Pg.247]

Near-infrared spectra were collected with a Nicolet 670 Nexus Fourier transform (FT) spectrometer.6 Solutions were thermally equilibrated at 37.0 0.1 °C prior to collecting spectra. The following two unique sets of near-infrared spectra were collected (1) first-overtone spectra (6500-5500 cm-1) with a 7.5 mm optical path length and (2) combination spectra (5000-4000 cm-1) with a 1.5 mm optical path length. Single-beam spectra were collected in triplicate as 256 coadded interfero-grams that were Fourier transformed to produce spectra with 1.94 cm-1 point spacing. [Pg.366]

Fig. 19 Main plot SAXS intensity (I) vs momentum transfer for a solution of 51 in acetonitrile (5.1 g L 1). The symbols and the solid line correspond to the experimental data points and the numerical fit using GNOM/DAMMIN simulated annealing, constraining the symmetry to the point group P432 (% = 1.397). Inset reconstructed low resolution particle shape for 51 obtained by the GNOM/DAMMIN fit (semitransparent spheres) superimposed onto the PM3 stationary point (space-filling model, iso-butyl groups substituted by methyl groups)... Fig. 19 Main plot SAXS intensity (I) vs momentum transfer for a solution of 51 in acetonitrile (5.1 g L 1). The symbols and the solid line correspond to the experimental data points and the numerical fit using GNOM/DAMMIN simulated annealing, constraining the symmetry to the point group P432 (% = 1.397). Inset reconstructed low resolution particle shape for 51 obtained by the GNOM/DAMMIN fit (semitransparent spheres) superimposed onto the PM3 stationary point (space-filling model, iso-butyl groups substituted by methyl groups)...
There is one unequal sequence of points for which the second derivative, when applied directly to the points, retains the second-order nature of an even point spacing. This was found by Sundqvist and Veronis [537] in 1970. Their stretching function was... [Pg.108]

The Feldberg expansion consists of a starting (first) box length of length H. Subsequent boxes are then defined such that box number i has length /5 -1 Hi. See Fig. B.l for this and the points spacing. Points spacing uses the transformation relations... [Pg.295]

In publishing, type is measured in points space is measured in picas. There are 72 points to an inch there are 6 picas to an inch. The size of the type you are reading on this page is 10 points.The column is 28 picas wide,and the text page is 44 picas long. [Pg.356]

The point space definition is pursued here. Here reference is given to the coordinate system defined by our origin and the basis vectors a, b, c in Eq. 1.2,... [Pg.12]

In the coupled system the lES runs in a T159 spectral resolution and the grid point space is represented in the reduced Gaussian grid (Hortal and Simmons 1991). The vertical coordinate system is given by 60 hybrid sigma-pressure levels. In order... [Pg.112]

As a second example, consider the growth of the diamond lattice about a central point. Space group 227 (Fd3m O ) describes the diamond crystal structure and we see from this information that the structure is non-symmorphic and that while the factor group is of order 48, not all of these symmetry operations are common to the point symmetry group Oh. Table 2.5 lists the point symmetry operations of O, in which the non-primitive translation j)... [Pg.63]


See other pages where Point space is mentioned: [Pg.209]    [Pg.110]    [Pg.25]    [Pg.216]    [Pg.357]    [Pg.16]    [Pg.164]    [Pg.180]    [Pg.186]    [Pg.233]    [Pg.318]    [Pg.121]    [Pg.121]    [Pg.6]    [Pg.248]    [Pg.34]    [Pg.370]    [Pg.56]    [Pg.64]    [Pg.429]    [Pg.12]    [Pg.109]    [Pg.213]    [Pg.12]    [Pg.36]    [Pg.620]    [Pg.229]    [Pg.9]    [Pg.321]    [Pg.343]    [Pg.199]   
See also in sourсe #XX -- [ Pg.285 ]




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