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Mathematics polynomial equations

The so-called S-FIT method and the sum-of-broadened-rectangles (SOBR) method both use more sophisticated mathematical assumptions to model the shape of the S-phase region of the histogram. A polynomial equation (S-FIT) or a series of broadened Gaussian dis-... [Pg.136]

When discussing diffusion, one inevitably needs to solve diffusion equations. The Laplace transform has proven to be the most effective solution for these differential equations, as it converts them to polynomial equations. The Laplace transform is also a powerful technique for both steady-state and transient analysis of linear time-invariant systems such as electric circuits. It dramatically reduces the complexity of the mathematical calculations required to solve integral and differential equations. Furthermore, it has many other important applications in areas such as physics, control engineering, signal processing, and probability theory. [Pg.353]

Prediction of the log reduction of an inoculated organism as a function of acid concentration, time, and temperature can also be done by a mathematical model developed for this purpose, using the second-order polynomial equation to fit the data. The following tests justified the reliability of the model the analysis of variance for the response variable indicated that the model was significant (P < 0.05 and R2 = 0.9493) and had no significant lack of fit (P > 0.05). Assumptions underlying the ANOVA test were also investigated and it was demonstrated that with the normal probability plot of residuals, plot of residuals versus estimated values for the responses, and plot of residuals versus random order of runs, that the residuals satisfied the assumptions of normality, independence, and randomness (Jimenez et al., 2005). [Pg.235]

The relative merits of these different methods can be compared by differentiating a known mathematical function. The model we will use is y = x + x /2), X = 0. .. 4, at X = 2. Various levels of noise are imposed on the signal y (Table 3.2). The resulting derivatives are shown in Table 3.3. As the noise level reduces and tends to zero, the derivative results from applying the five-point polynomial (Equation 3.4) converge more quickly towards the correct noise-free value of 3 for the first derivative, and 1 for the second derivative (Equation 3.5). As with polynomial smoothing, the Savitzky-Golay differentiation technique is available with many commercial spectrometers. [Pg.60]

Table 27.12 gives common relationships for determination of the thermal conductivity of selected major seed types. To improve the fit of data to mathematical expressions, polynomial equations are also used or temperature is introduced into the expression [39,56],... [Pg.579]

The information in Figure 3.7 can be converted to molar concentrations, after which we can apply the usual mathematical methods used in a chemical kinetics investigation. Figure 3.8 shows sucrose concentration as a function of time for Run 19. The polynomial equation fitting sucrose concentration to time is displayed in Figure 3.8. Note that it has the general form... [Pg.41]

Therefore, research focused on the development of new membrane materials and up-scaling for production is still important. In that direction, and in order to understand better the membrane behaviour of PEO-PBT copolymers, the CO2 permeability (Table 12.1) were fitted to polynomial mathematical models (Equation 12.2), and plotted versus the molecular weight (M ) of the PEO block, as shown in Figure 12.2. [Pg.232]

Coulson attended Clifton College in Bristol where his "wise and cunning mathematics master" H. C. Beaven, a Balliol graduate, invited him to a lecture at the University of Bristol by Selig Brodetsky, a rather well-known applied mathematician. Years later, Coulson remembered how flattered he was to be asked to a lecture at the university and also how impressed he was by what he heard. The speaker explained how a specific root-squaring process could be used to find the roots of a polynomial equation. The event marked him for life. [Pg.158]

As we shall see for every kind of solution, pH calculations are, as a rule, always possible from a purely mathematical point of view. Indeed, the expressions of equilibria and those of charge and mass balances are always required to provide the same number of equations as the number of unknowns. However, the resulting polynomial equations may be difficult to solve because their order is higher than 2 in the existing unknown. Then numerical calculations may be made. Additionally, they can be performed with pocket calculators. Another way is to make approximations, which greatly simplify the solution of the problem (see below) in Eqs. (5.5) and (5.6), no parameter is characteristic of some particular acid, provided it is strong. The result is that every strongly acidic solution exhibits the same pH value for the same analytical concentration in the above Eqs. (5.1), (5.3), and (5.4), we have not set up... [Pg.79]

In the past, people was apt to think that the best way to increase the prediction ability of the mathematical models obtained from data processing is to find a function to fit the training data set as close as possible. In other words, best training could assure best prediction result. But this concept has been found to be not correct in the practice of the application work of artificial neural networks or nonlinear regression with polynomial equations. Therefore, it has become an imminent task to find a strict mathematical theory for solving the problem of overfitting [68]. [Pg.12]

The field of process dynamics and control often requires the location of the roots of transfer functions that usually have the form of polynomial equations. In kinetics and reactor design, the simultaneous solution of rate equations and energy balances results in mathematical models of simultaneous nonlinear and transcendental equations. Methods of solution for these and other such problems are developed in this chapter. [Pg.3]

For the case of polynomial equations, the solution values of x which satisfy the equation are frequently called roots of flic polynomial. In general these may be real numbers or complex numbers. For the case of transcendental equations such as Eq. (3.3) the solution values are typically called zeros of the function. Mathematically the terms roots and zeros are used interchangeably. [Pg.43]

In the first study by Tan et al. in order to obtain a mathematical relationship between the structural components of the nonsolvent additives and the gas performance, each nonsolvent additive was split into structural components such as -CH3, -CH2-, =CH- and = C = groups. Table 20 shows the grouping of all the nonsolvent additives. Several linear polynomial 1st and 2nd order equations as well as nonlinear polynomial equations were attempted to derive an empirical correlation between the number of structural components and gas permeation data. A correlation could only be determined for the CO2/CH4 permeance ratio. This model is... [Pg.278]

For some reactions, the equation for x in terms of K ma> be a higher-order polynomial. If an approximation is not valid, one approach to solving the equation is to use a graphing calculator or mathematical software to find the roots of the equation. [Pg.494]

Let us notice that due to orthogonality of Legendre s polynomials many functions can be represented as a series, which is similar to Equation (1.162), and this fact is widely used in mathematical physics. Now, we will derive the differential equation, one of the solutions of which are Legendre s functions. [Pg.57]

Mathematically this operation can be described by the same equation (eq. (40.13)) as derived for polynomial smoothing, namely ... [Pg.547]

The radial functions Sni p) and R i(r) may be expressed in terms of the associated Laguerre polynomials L p), whose definition and mathematical properties are discussed in Appendix F. One method for establishing the relationship between Sniip) and L p) is to relate Sni p) in equation (6.50) to the polynomial L p) in equation (F.15). That process, however, is long and tedious. Instead, we show that both quantities are solutions of the same differential equation. [Pg.171]

At this point, we may proceed in one of two ways, which are mathematically equivalent. In the first procedure, we note that from the generating function (E.l) for Legendre polynomials Pi, equation (J.3) may be written as... [Pg.341]

The mathematics of fitting a polynomial by least squares are relatively straightforward, and we present a derivation here, one that follows Arden, but is rather generic, as we shall see Starting from equation 66-4, we want to find coefficients (the at) that minimize the sum-squared difference between the data and the function s estimate of that data, given a set of values of X. Therefore we first form the differences ... [Pg.442]

Full second-order polynomial models used with central composite experimental designs are very powerful tools for approximating the true behavior of many systems. However, the interpretation of the large number of estimated parameters in multifactor systems is not always straightforward. As an example, the parameter estimates of the coded and uncoded models in the previous section are quite different, even though the two models describe essentially the same response surface (see Equations 12.63 and 12.64). It is difficult to see this similarity by simple inspection of the two equations. Fortunately, canonical analysis is a mathematical technique that can be applied to full second-order polynomial models to reveal the essential features of the response surface and allow a simpler understanding of the factor effects and their interactions. [Pg.254]

In this chapter we consider the performance of isothermal batch and continuous reactors with multiple reactions. Recall that for a single reaction the single differential equation describing the mass balance for batch or PETR was always separable and the algebraic equation for the CSTR was a simple polynomial. In contrast to single-reaction systems, the mathematics of solving for performance rapidly becomes so complex that analytical solutions are not possible. We will first consider simple multiple-reaction systems where analytical solutions are possible. Then we will discuss more complex systems where we can only obtain numerical solutions. [Pg.146]

Regression generally means the fitting of mathematical equations to experimental data ( 3). Nonlinear regression, unlike linear regression, encompasses methods vdiich are not limited to fitting equations linear in the coefficients (e.g. simple polynomial forms). [Pg.203]


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