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Simple Scaling

In simple scaling, the criteria values are multiplied by 10 where K is a positive or negative integer including zero. This is the most common scaling method used in practice. If a criterion is to be minimized, its values should be multiplied by (-1) before computing the weighted score. [Pg.317]

Let T be the temperature, P the pressure, p the chemical potential, p the molar density, x = dpjdp)T= p dpldP)T the (isothermal) susceptibility, 5 m the molar entropy, the Helmholtz energy per mole, Cjz,m the isochoric molar heat capacity, and the isobaric molar heat capacity. The scaling law given by eq [Pg.328]

1 represents the singular part of the thermodynamic potential. To account for analytic background contributions it is convenient to introduce an analytic caloric background function Pq T) and an analytic mechanical background [Pg.328]

In order to normalize the scaling fields, the thermodynamic properties are made dimensionless with the aid of the critical parameters Tc and pc- [Pg.329]

The simplest theoretical prototype of the critical vapour-liquid transition is the lattice gas which is a reformulation of the 3D Ising model in terms of fluid variables. For the lattice gas the scaling fields are  [Pg.329]

Equation 10.17 represents a fundamental equation for the pressure as a function of chemical potential and temperature from which all other [Pg.329]


Another approach to the control of batching systems is to use a relatively simple scale indicator which does nothing but supply weight data to a controUer such as a PLC, which in turn controls the fiH and discharge system. The communications between the scale and controUer can be serial such as RS-232, or it can be an analogue signal such as 4-20 m A. While this system minimises operator interaction with the scale, it sacrifices speed and accuracy because of the relatively slow communications. [Pg.339]

The time constants characterizing heat transfer in convection or radiation dominated rotary kilns are readily developed using less general heat-transfer models than that presented herein. These time constants define simple scaling laws which can be used to estimate the effects of fill fraction, kiln diameter, moisture, and rotation rate on the temperatures of the soHds. Criteria can also be estabHshed for estimating the relative importance of radiation and convection. In the following analysis, the kiln wall temperature, and the kiln gas temperature, T, are considered constant. Separate analyses are conducted for dry and wet conditions. [Pg.49]

Experiments on a small scale with stoichiometric methane-air mixtures were carried out by Chan et al. (1980). Comparisons of results of these experiments with those performed by Moen et al. (1982) revealed that simple scaling is not possible for the results of explosions with very high flame speeds, in other words, flame speeds resulting from very intense turbulence. [Pg.84]

This estimate, which is based on simple scaling arguments, may be substantiated by calculating the free energy of a disordered Peierls chain, as we did in Ref. [31]. Treating the lattice vibrations classically, the final result for the kink... [Pg.53]

If a trial function 9 leads to a kinetic energy 1 and a potential energy Vx which do not fulfill the virial theorem (Eq. 11.15), the total energy (7 +Ei) is usually far from the correct result. Fortunately, there exists a very simple scaling procedure by means of which one can construct a new trial function which not only satisfies the virial theorem but also leads to a considerably better total energy. The scaling idea goes back to a classical paper by Hylleraas (1929), but the connection with the virial theorem was first pointed out by Fock.5 It is remarkable how many times this idea has been rediscovered and published in the modern literature. [Pg.219]

The positive results obtained at production scale give us confidence in the validity of our approach. Derivation of a simple scaling factor enabled us to conduct a series of experiments in a small pilot plant which would have been expensive and time-consuming on a production scale. Time series analysis not only provided us with estimates of the process gain, dead time and the process time constants, but also yielded an empirical transfer function which is process-specific, not one based on... [Pg.485]

More complete analyses have been effected [6,23], but we shall present here a simple scaling procedure in order to isolate the essential nature of the wetting ridge. Consider a zone of typical linear dimension to in the vicinity of the triple line, which corresponds to the solid disturbed by the capillary force 7 sin 0. Within this region, a stress of order of... [Pg.290]

Given that for a rubber compound, F = 3 ji, comparison of Eqs. (11) and (14) shows that the simple scaling argument is in agreement with the more exact expression to within a factor of about 2. [Pg.294]

The reason why simple scaling considerations do not lead to a unique result for the exponent a is due to the fact that the entanglement problem as a geometrical phenomenon contains two independent lengths the lateral distance between the chains s = (L/V) 1/2 and the step width of the random walk... [Pg.54]

A simple scaling law has been postulated to define the relationship between polymer length and Rg under various solvent conditions (Flory, 1953) ... [Pg.278]

The molar mass dependence of the intrinsic viscosity of rigid chain polymers cannot be described by a simple scaling relation in the form of Equation (36) with molar mass independent of K and a. over a broad molar mass range. Starting from the worm-like chain model, Bohdanecky proposed [29] the linearizing equation... [Pg.220]

In the first part to follow, the equations of motion of a soft solid are written in the harmonic approximation. The matrices that describe the potential, and hence the structure, of the material are then considered in a general way, and their properties under a normal mode transformation are discussed. The same treatment is given to the dissipation terms. The long wavelength end of the spectral density is of interest, and here it seems that detailed matrix calculations can be replaced by simple scaling arguments. This shows how the inertial term, usually absent in molecular problems, is magnified to become important in the continuum limit. [Pg.244]

The only difference with the exchange case is that the functional K [p] does not obey a simple scaling relation in Eq. (197) as in the exchange case. We determine the functional form of by requiring our approximate to satisfy the relation due to Averill and Painter [122] and Levy and Perdew [121]... [Pg.161]

With this correction all but one computed electron correlation energy fell within 10% of the exact solution. As Table 11 shows, the very simple scaling correction yields huge improvements on modest initial electron correlations. The use of the correction factor implies the loss of the variational principle and does not account for the use of different basis sets for example, the Dunning double-zeta basis set for Be is different for LiH [24, 25]. [Pg.437]

Scale-up of spin-filters has been often studied in the recent years, and simple scale-up procedures have been proposed by Yabannavar et al. [81] and Deo et al. [13]. Yabannavar et al. [81] suggested a procedure based on keeping the ratio of permeation drag to lift force constant for the different production scales, in... [Pg.151]

Although the fouling problem seems not yet to be completely solved, the simple scale-up, combined with reproducibility of repeated TFF runs, membrane reusability, and suitabihty of a TFF system for different cell lines and culture media [1] make TFF an attractive choice for mammahan cell separation. [Pg.156]

In this example, we show that for the same superficial contact time, the fluidized bed results in a different conversion, which is not the case for a fixed-bed reactor. As will be presented in Chapter 6, the complicated hydrodynamics of fluidized beds does not allow such simple scale-up rales to emerge. [Pg.502]


See other pages where Simple Scaling is mentioned: [Pg.96]    [Pg.455]    [Pg.83]    [Pg.82]    [Pg.223]    [Pg.390]    [Pg.612]    [Pg.674]    [Pg.351]    [Pg.111]    [Pg.296]    [Pg.50]    [Pg.479]    [Pg.44]    [Pg.72]    [Pg.381]    [Pg.291]    [Pg.382]    [Pg.293]    [Pg.143]    [Pg.118]    [Pg.202]    [Pg.100]    [Pg.6]    [Pg.192]    [Pg.68]    [Pg.159]    [Pg.158]    [Pg.230]    [Pg.19]    [Pg.228]    [Pg.71]    [Pg.183]    [Pg.76]   


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