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Distribution assumed

If this criterion is based on the maximum-likelihood principle, it leads to those parameter values that make the experimental observations appear most likely when taken as a whole. The likelihood function is defined as the joint probability of the observed values of the variables for any set of true values of the variables, model parameters, and error variances. The best estimates of the model parameters and of the true values of the measured variables are those which maximize this likelihood function with a normal distribution assumed for the experimental errors. [Pg.98]

For turbulent flow, with roughly uniform distribution, assuming a constant fricdion factor, the combined effect of friction and inerrtal (momentum) pressure recovery is given by... [Pg.658]

Using the algebra of random variables we ean solve the probability of interferenee between the two toleranee distributions, assuming that the variables follow a... [Pg.352]

Note the parameters for the 3-parameter Weibull distribution, xo and 6, ean be estimated given the mean, /i, and standard deviation, cr, for a Normal distribution (assuming [3 = 3.44) by ... [Pg.357]

The relation between the mean velocity and the velocity at the axis is derived using this expression in Chapter 3. There, the mean velocity u is shown to be 0.82 times the velocity us at the axis, although in this calculation the thickness of the laminar sub-layer was neglected and the Prandtl velocity distribution assumed to apply over the whole cross-section. The result therefore is strictly applicable only at very high Reynolds numbers where the thickness of the laminar sub-layer is vety small. At lower Reynolds numbers the mean velocity will be rather less than 0.82 times the velocity at the axis. [Pg.683]

The relaxation time for each pore will still be expressed by Eq. (3.6.3) where each pore has a different surface/volume ratio. Calibration to estimate the surface relaxivity is more challenging because now a measurement is needed for a rock sample with a distribution of pore sizes or a distribution of surface/volume ratios. The mercury-air or water-air capillary pressure curve is usually used as an estimator of the cumulative pore size distribution. Assuming that all pores have the same surface relaxivity and ratio of pore body/pore throat radius, the surface relaxivity is estimated by overlaying the normalized cumulative relaxation time distribution on the capillary pressure curve [18, 25], An example of this process is illustrated in Figure 3.6.5. The relationship between the capillary pressure curve and the relaxation time distribution with the pore radii, assuming cylindrical pores is expressed by Eq. (3.6.5). [Pg.329]

The deposition rate of the attached fraction, plotted in Figure 3, is calculated from the aerosol size distribution assuming diffusion and electrophoresis to be the most important deposition mechanisms (Raes et al.,1985a). The accuracy of the absolute values was checked by forming the aerosol mass balance after the generation of a high aerosol concentration.In Table II is compared the decay of the... [Pg.309]

Another way of looking at the Boltzmann distribution assumes that the energy spectrum consists of closely spaced, but fixed energy levels, e . The probability that level u is populated is specified in terms of the canonical distribution... [Pg.449]

Figure 3. Particle scattering coefficient, China Lake, CA (1979 average). The distribution is calculated from 254 measured aerosol volume distributions assuming... Figure 3. Particle scattering coefficient, China Lake, CA (1979 average). The distribution is calculated from 254 measured aerosol volume distributions assuming...
Figure 4.11 Relative abundance for D L -stereoisomer groups of the oligo-tryptophan n-mers (n = 7 and 10, respectively), obtained after two racemic NCA-Trp feedings (a) in the absence (n = 7) and (b) in the presence of POPC liposomes (n = 10). The relative abundances of the stereoisomer subgroups (dark-gray columns) are mean values of three measurements. Standard deviations are given as error bars. The white columns correspond to the theoretical distribution, assuming a statistical oligomerization. (From Blocher et al., 2001.)... Figure 4.11 Relative abundance for D L -stereoisomer groups of the oligo-tryptophan n-mers (n = 7 and 10, respectively), obtained after two racemic NCA-Trp feedings (a) in the absence (n = 7) and (b) in the presence of POPC liposomes (n = 10). The relative abundances of the stereoisomer subgroups (dark-gray columns) are mean values of three measurements. Standard deviations are given as error bars. The white columns correspond to the theoretical distribution, assuming a statistical oligomerization. (From Blocher et al., 2001.)...
Figure 60. Comet-tail CO+(A1l —>X2 2+) spectra from (a, c) luminescent ion-molecule reaction C++02- C0+ + 0 at lab = 5 eV (b,d), charge-transfer reaction Ar+ +CO->CO+ + Ar at lab=1000 eV. Experimental spectra (a, b) were obtained with 2-nm spectral resolution. Tabulated band heads for CO+ (A— BX) system are indicated. Spectral lines designated as Ar(II) and C(I) do not belong to CO+ emission. Dashed portion of curves was not actually measured. Spectra simulated by computer calculations are given in diagrams (c and d). Rotational distributions assumed in simulation calculations were thermal with T= 45,000°K (c) and 1000°K ( Figure 60. Comet-tail CO+(A1l —>X2 2+) spectra from (a, c) luminescent ion-molecule reaction C++02- C0+ + 0 at lab = 5 eV (b,d), charge-transfer reaction Ar+ +CO->CO+ + Ar at lab=1000 eV. Experimental spectra (a, b) were obtained with 2-nm spectral resolution. Tabulated band heads for CO+ (A— BX) system are indicated. Spectral lines designated as Ar(II) and C(I) do not belong to CO+ emission. Dashed portion of curves was not actually measured. Spectra simulated by computer calculations are given in diagrams (c and d). Rotational distributions assumed in simulation calculations were thermal with T= 45,000°K (c) and 1000°K (</). 93...
Packer and Rees [3] extended the expression derived by Murday and Cotts [7] to include the effects of a droplet size distribution, assuming a log-normal distribution. By curve fitting they were able to determine the principal parameters of such a distribution from the experimental R-values. In the presence of a distribution of sizes, the observed echo attenuation ratio R is expressed in terms of the calculated attenuation of individual droplets, R ... [Pg.157]

Figure 8. Dipole coupling shifts (experimental points) as function of coverage in Stage 1, compared with theoretical shifts for random (S ) and regular (S oc 3/2) distributions assuming free molecule polarizabilities... Figure 8. Dipole coupling shifts (experimental points) as function of coverage in Stage 1, compared with theoretical shifts for random (S ) and regular (S oc 3/2) distributions assuming free molecule polarizabilities...
Figure 10. (Top) experimental values (X) of the relative IR band intensity compared with Q2 X , where Q is based on ay = 0.18A3 and d = 1.85A (bottom,) coverage dependence of the dipole coupling shift (experimental points) compared with theoretical shifts for random (S a ) and regular (S a 3/2) distributions, assuming the same values of ay and d, and with at = 2086 cm 1... Figure 10. (Top) experimental values (X) of the relative IR band intensity compared with Q2 X , where Q is based on ay = 0.18A3 and d = 1.85A (bottom,) coverage dependence of the dipole coupling shift (experimental points) compared with theoretical shifts for random (S a ) and regular (S a 3/2) distributions, assuming the same values of ay and d, and with at = 2086 cm 1...
The one-compartment model of distribution assumes that an administered drug is homogeneously distributed throughout the tissue fluids of the body. For instance, ethyl alcohol distributes uniformly throughout the body, and therefore any body fluid may be used to assess its concentration. The two-compartment model of distribution involves two or multiple central or peripheral compartments. The central compartment includes the blood and extracellular fluid volumes of the highly perfused organs (i.e., the brain, heart, liver, and kidney, which receive three fourths of the cardiac output) the peripheral compartment consists of relatively less perfused tissues such as muscle, skin, and fat deposits. When distributive equilibrium has occurred completely, the concentration of drug in the body will be uniform. [Pg.12]

Figure 2 The expected electron energy distribution assuming a classical scattering process (dashed line). The initial photoelectron spectrum is shown as solid line. Figure 2 The expected electron energy distribution assuming a classical scattering process (dashed line). The initial photoelectron spectrum is shown as solid line.
The administration of a drug by a rapid intravenous injection places the drug in the circulatory system where it is distributed (see section 2.7.1) to all the accessible body compartments and tissues. The one compartment model (Figure 8.3(a)) of drug distribution assumes that the administration and distribution of the drug in the plasma and associated tissues is instantaneous. This does not happen in practice and is one of the possible sources of error when using this model to analyse experimental pharmacokinetic data. [Pg.163]

Generally, good agreement was found between the experimentally observed and the statistically predicted population distributions assuming diradicals (as shown above) are formed initially instead of their alkene isomers. Table I summarizes results which show the comparison between the experimentally determined average product CO vibrational energies and the statistically expected values. [Pg.405]

We note first that immediately following the injection of a sample at the head of the channel, the flow of carrier is stopped briefly to allow time for the sample particles to accumulate near the appropriate wall. As the particles concentrate near the wall, the growing concentration gradient leads to a diffusive flux which counteracts the influx of particles. Because channel thickness is small (approximately 0.25 mm), these two mass transport processes quickly balance one another, leading to an equilibrium distribution near the accumulation wall. This distribution assumes the exponential form... [Pg.222]

To determine precision, we need to know something about the manner in which data is customarily distributed. For example, high precision (i.e., the data are very close together) produces a very narrow distribution, while low precision (i.e., the data are spread far apart) produces a wide distribution. Assuming that the data are normally distributed (which holds true for many cases and can be used as an approximation in many other cases) allows us to use the well understood mathematical distribution known as the normal or Gaussian error distribution. The advantage to using such a model is that we can compare the collected data with a well understood statistical model to determine the precision of the data. [Pg.12]

A site distribution assuming no lateral interaction was determined using Steele s method (4) for neon on titanium dioxide. The site energies and distribution are given in Table II (columns 3 and 5). With this site distribution, Equations 2.3 and 3.6 of Aston, Tykodi, and Steele (2) were used to calculate the isotherm and differential heats of adsorption for neon on titanium dioxide which already has been treated by Aston, Tykodi, and Steele. Table II (columns 2 and 4) also gives the site distribution of Aston, Tykodi, and Steele. In Figure 4,... [Pg.334]

Here ey is the cross section for a collisionally induced transition and v is the thermal velocity of the colliding particle, < av > is the average value of ov for a Maxwellian velocity distribution. Assuming a typical dipole moment of 1 Debye, a = 1CT15 cm"2, v = 5 x 104 cm/s, one obtains the density n % 103/X3. Thus for the detection of an emission line in the centimeter-wave region (X = 1 cm) the density within the cloud is expected to be of the order of 103 cm-3. On the other hand, a detection of a millimeter-wave transition in emission at X = 1 mm requires densities of the order of 10s to 106 particles/cm3. [Pg.49]


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See also in sourсe #XX -- [ Pg.16 ]




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