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Polynomial, fitting with

An alternative approach is to apply stronger fields and only use energies calculated for positive field strengths in generating the polynomial fit. In this case the energy is a function of both odd and even powers in the polynomial fit. We will show that the dipole moments derived from our non-BO calculations with the procedure that uses only positive fields and polynomial fits with both even and odd powers match very well the experimental results. Thus in the present work we will show results obtained using interpolations with even- and odd-power polynomials. Methods other than the finite field method exist where the noise level in the numerical derivatives is smaller (such as the Romberg method), but such methods still do not allow calculation of odd-ordered properties in the non-BO model. [Pg.456]

Figure 3.6. Polynomial fit with a window width of 13 points. The smoothed value of data point 7is shown as X. Figure 3.6. Polynomial fit with a window width of 13 points. The smoothed value of data point 7is shown as X.
Gan, F. Ruan, G. Mo, J. (2006). Baseline correction by improved iterative polynomial fitting with automatic threshold. Chemometrics and Intelligent Laboratory Systems, Vol.82, No.l (May 2006), pp. 59-65, ISSN 0169-7439... [Pg.323]

However, Wilhelm et al. (31) noted that the advantage of equation (37) over polynomial fits with an equal number of coefficient is that, it correctly correlates solubility and temperature with a significantly smaller standard deviation. The differentiation of equation (37) yields the different thermodynamic functions, as... [Pg.72]

A eV 2 = 10.428 A eV, = -2.1316 A eV, uq = 0.5009 A. For the p block cations in their maximum oxidation state in bonds to chalcogenides a simpler second order polynomial fit with 02 = 1.9108 A eV, = 0.8287 A eV, flo = 0.2946 A (gray broken line in Fig. 8) can be used to predict the systematically lower b values, since the softness difference for aU observed cases was > 0.05 eV . Analogous polynomial fits (based on the smaller set of reference data available at that time) have been used to derive the systematic b values in the softBV parameter set. [Pg.118]

Lane improved on these tables with accurate polynomial fits to numerical solutions of Eq. 11-17 [16]. Two equations result the first is applicable when rja 2... [Pg.15]

FIG. 7-2 Linear analysis of catalytic rate equations, a), (h) Sucrose hydrolysis with an enzyme, r = 1curve-fitted with a fourth-degree polynomial and differentiated for r — (—dC/dt). Integrated equation,... [Pg.689]

SEC measurements were made using a Waters Alliance 2690 separation module with a 410 differential refractometer. Typical chromatographic conditions were 30°C, a 0.5-ml/min flow rate, and a detector sensitivity at 4 with a sample injection volume of 80 fil, respectively, for a sample concentration of 0.075%. All or a combination of PEO standards at 0.05% concentration each were used to generate a linear first-order polynomial fit for each run throughout this work. Polymer Laboratories Caliber GPC/SEC software version 6.0 was used for all SEC collection, analysis, and molecular weight distribution overlays. [Pg.502]

FIGURE 35.3 Free-energy functions for reactant (AE) and product Ag (AE) of an electron transfer reaction as calculated using umbrella sampling within a simple dipolar diatomic solvent. AG° is the reaction free energy. Solid lines are polynomial fittings to the simulated points. Dashed lines are parabolic extrapolations from the minimum of the curves. (From King and Warshel, 1990, with permission from the American Institute of Physics.)... [Pg.666]

Fig. 40.24. Polynomial smoothing window of 7 data points fitted with polynomials of degrees 0,1,2, 3 and 4. Fig. 40.24. Polynomial smoothing window of 7 data points fitted with polynomials of degrees 0,1,2, 3 and 4.
Figure 3b. A plot of the Mean Cnrvatnre data versns the 40% Compression Deflection valnes for the urethane foams made with constant tin catalyst concentration calculation by RS/1 for a polynomial fit. Figure 3b. A plot of the Mean Cnrvatnre data versns the 40% Compression Deflection valnes for the urethane foams made with constant tin catalyst concentration calculation by RS/1 for a polynomial fit.
The figure shows a polynomial fit to a dataset calculated according to a standard least squares algorithm (solid line) this is compared with a series of attempts to find a fit to the same data using a genetic algorithm. [Pg.3]

However, this collection of convolution coefficients appears nowhere in the S-G tables. The nine-point S-G second derivative with a Quadratic or Cubic polynomial fit has the coefficients ... [Pg.364]

Recently, a U.S.S.R.-Czechoslovokian research group have reported 14C data for dated wine samples from the Caucasus Mountains [27]. Their results are in fairly close agreement with our results for the time of overlapping data (figure 5). If the anomalous data for A.D. 1943 are omitted, the fifth order polynomial fit to the data yields a 5 per mil peak to trough amplitude with a phase lag of 4 years behind sunspot numbers. The amplitude... [Pg.240]

The initial rate is given by the numerical value of m1 from polynomial fitting. The rate proved to be a function of three concentration variables, [1], [PyO] and [PPh3]. Values of the rate were determined in series with two variables maintained constant and the third varied. This led to this tentative rate equation ... [Pg.167]

Numerical differentiation may be quite sensitive to the correlating equation. In problem PI.03.01, the results with four different curvefits do not agree well although the curvefits themselves are statistically satisfactory. In problem PI.0302, however, the agreement between the higher polynomial fits is more nearly acceptable. [Pg.16]

The data are plotted as (B,A) and (C,A) and fitted with cubic polynomials, although the fits are poor. Then they are differentiated to obtain the derivatives,... [Pg.251]

Procedures for curve fitting by polynomials are widely available. Bell shaped curves usually are fitted better and with fewer constants by ratios of polynomials. Problem P5.02.02 compares a Gamma fit with those of other equations, of which a log normal plot is the best. In figuring chemical conversion, fit of the data at low values of Ett) need not be highly accurate since those regions do not affect the overall result very much. [Pg.509]

The relationship between the temperature difference, AT, and the input power is shown in Fig. 4.5 for microhotplate simulations and measurements. The simulated values are plotted together with the mean value of the experimental data for a set of three hotplates of the same wafer. The experimental curve was fitted with a second-order polynomial according to Eq. (3.24). As a result of the curve fit, the thermal resistance at room temperature, tjo, is 5.8 °C/mW with a standard deviation of 0.2 °C/mW, which is mainly due to variations in the etching process. [Pg.37]

The modulus data were fitted with a second degree polynomial equation, and these functions were used in the calculations of the thermal stresses from Equations 1 through 3. The polynomial coefficients and the correlation coefficient for each sample are given in Table III. [Pg.225]

As with all window-based smoothers, the choice of the window size in polynomial smoothers is very imponani. Another decision to make for polynomial smoothers is the order of the polynomial to be fit (Barak, 1995). Typically, a second- or third-order polynomial is used. An example of applying a polynomial smoother is shown in Figure 3.7, wliere a second-order polynomial is fit with window sizes of 7, 13, and 25 points. As the window size increases, the noise is continually reduced. Howe -er, when the window is too large, sharp peaks may be removed and the remaining peaks distorted. This is demonstrated in Figure 3.8 where a spectrum is shown before (solid) and after (dashed) applying a 49-point second-order polynomial smoother. [Pg.200]

Figure 5. Calibration Curves Fitted with Polynomial and Yau-Malone Function Followed by Polynomial. Figure 5. Calibration Curves Fitted with Polynomial and Yau-Malone Function Followed by Polynomial.

See other pages where Polynomial, fitting with is mentioned: [Pg.277]    [Pg.277]    [Pg.13]    [Pg.4]    [Pg.350]    [Pg.304]    [Pg.430]    [Pg.117]    [Pg.389]    [Pg.396]    [Pg.337]    [Pg.295]    [Pg.371]    [Pg.150]    [Pg.241]    [Pg.118]    [Pg.258]    [Pg.40]    [Pg.138]    [Pg.457]    [Pg.72]    [Pg.289]    [Pg.403]    [Pg.129]    [Pg.472]    [Pg.16]   
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