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Numerals—continued

Contimious liquid extraction techniques are used when the sample volume is large, the distribution constant is small, or the rate of extraction is slow. The efficiency of extraction depends on many factors including the viscosity of the phases, the magnitude of the distribution constant, the relative phase volumes, the interfacial surface area, and the relative velocity of the phases. Numerous continuous extractors using llghter-than-water and heavier-than-water solvents vee been described [3,2 7,42,73,74]. Generally, either the ligi Pr or heavier density... [Pg.385]

Before discussing how clinical data are described and analyzed, it is helpful to introduce several categories of data. Data are numerical representations of information, and different forms of numerical information have different characteristics that permit (or do not permit) certain analyses to be conducted on them. In clinical research, the term variable is often used when describing data for a particular characteristic of interest, since values for participants in a clinical trial will vary from one individual to another. Clinical data can fall within several categories, including numerical (continuous and discrete) data and categorical (ordinal and nominal) data. [Pg.84]

It is well known (see, e.g.. Ref. 13) that the normal form transformations do not converge in the sense that normalization to all orders generally does not yield a meaningful result. However, this is of no consequence for our purposes. We view the technique more as the input to a numerical method for realizing the NHIM, its stable and unstable manifolds, and the TS. In this sense the limitations of machine precision make normalization beyond a certain finite order meaningless. This is a local result valid in the neighborhood of the equilibrium point of center center saddle type. However, once the phase-space structure is established locally, it can be numerically continued outside of the local region. [Pg.186]

In contrast to the patchwork-like Munsell system, the CIE system and its modifications (developed by the International Commission on Illumination, CIE, in 1931) create numerically continuous color spaces. They are based on the principle of tricliromaticity of vision which states that the... [Pg.35]

It can be concluded from the various results described above that numerous continuous efforts have been devoted to the synthesis of enantiopure epoxides over the last twenty to thirty years which has led to important fundamental knowledge on this topic. Unfortunately, many of these approaches still suffer from severe limitations as far as large-scale (industrial) applications are concerned. This is particularly the case for direct epoxidation of alkenes using monooxygenases. Indeed, most of these biocatalytic routes imply multienzy-matic processes, and/or are hampered by substrate and/or product inhibition leading to low productivity. Highly sophisticated processes had therefore to be set up in order to partially overcome these drawbacks. [Pg.185]

The velocity of an individual phase front is uniquely determined by the properties of the medium and the forcing parameters. For wave trains, it additionally depends on the spatial period A of a train. Figure 7.2b shows dependences F(A) for two different values of the coefficient /3, obtained by numerical continuation of wave train solutions of equation (7.1) with n = 1. When (3 = 5.0, velocity V remains positive for all spatial periods. This means that both a solitary kink and any kink train in such a medium possess the right chirality. In contrast to this, kinks move at a positive velocity (and have the right chirality) only for sufficiently short spatial periods at /3 = 1.8. At a critical spatial period Ac, the propagation velocity of the train vanishes and F(A) <0 when A > Ac. Thus, solitary kinks and kink trains with large periods have the opposite left chirality in the latter case. [Pg.216]

Ringland, J. Rapid reconnaissance of a model of a chemical oscillator by numerical continuation of a bifurcation feature of codimension-2. J. Chem. Phys. 1991, 95, 555-562. [Pg.168]

A 0) s numeric (continuous, discrete) measurable explanatory (independent) controllable... [Pg.172]

State bifurcations, arise. Two widely used packages that implement numerical continuation methods are AUTO (Doedel et al., 1991) and CONT (Marek and Schreiber, 1991). These programs trace out curves of steady states and follow the properties of limit cycles by using techniques similar to the predictor-corrector approach described above to improve their computational efficiency. An example is shown in Figure 7.8. [Pg.151]

To afford the reader some insight into how numerical continuation methods work, we offer two examples. The problems we tackle are trivial they are easily... [Pg.151]

Table 7.1 Exact Roots and Numerical Continuation Approximations for eq. (7.13)... Table 7.1 Exact Roots and Numerical Continuation Approximations for eq. (7.13)...
The procedures outlined here are, in a more sophisticated form, those that go into a numerical continuation package. Starting from a reference solution at some chosen set of parameters, the derivatives of the steady-state or oscillatory solutions and of the Jacobian are estimated with respect to the parameters of interest... [Pg.154]

We employ a method of numerical continuation which has been earlier developed into a software tool for analysis of spatiotemporal patterns emerging in systems with simultaneous reaction, diffusion and convection. As an example, we take a catalytic cross-flow tubular reactor with first order exothermic reaction kinetics. The analysis begins with determining stability and bifurcations of steady states and periodic oscillations in the corresponding homogeneous system. This information is then used to infer the existence of travelling waves which occur due to reaction and diffusion. We focus on waves with constant velocity and examine in some detail the effects of convection on the fiiont waves which are associated with bistability in the reaction-diffusion system. A numerical method for accurate location and continuation of front and pulse waves via a boundary value problem for homo/heteroclinic orbits is used to determine variation of the front waves with convection velocity and some other system parameters. We find that two different front waves can coexist and move in opposite directions in the reactor. Also, the waves can be reflected and switched on the boundaries which leads to zig-zag spatiotemporal patterns. [Pg.725]

Allgower, E. and Georg, K., 1990, Numerical continuation methods-An introduction . Springer Verlag. [Pg.838]

AG90] Allgower E. L. and Georg K. (1990) Numerical Continuation Methods. Springer. [Pg.277]

E. L. Allgowerand K. Georg, Numerical Continuation Methods. An Introduction , Springer Series in Computational Mathematics, Vol. 13, Springer-Verlag, Berlin, 1990. [Pg.543]


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