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Derivatives continuous functions

V (ro) is continuous and has continuous lirst derivatives over the interval [0.271 ], which is the complete interval of ffi. It is convenient to rename the interval [ n, tc] (which is the same as [0. 27t ]) for the following discussion. Any continuous function can he repi esented ovei this interval by the Fourier. ieries... [Pg.119]

It is said in this case that the functional J has the derivative at the point u. Let V be the space dual of V, i.e. the space of all linear continuous functionals on V. If the operator J V —> V is defined such that for each u gV the derivative can be found at the point u, then the functional J is called differentiable. [Pg.22]

The functions v,aij,Sij v) represent the velocity, components of the stress tensor and components of the rate strain tensor. The dot denotes the derivative with respect to t. The convex and continuous function describes the plasticity yield condition. It is assumed that the set... [Pg.309]

Here i —> i is the convex and continuous function describing a plasticity yield condition, the dot denotes a derivative with respect to t, n = (ni,ri2) is the unit normal vector to the boundary F. The function v describes a vertical velocity of the plate, rriij are bending moments, (5.175) is the equilibrium equation, and equations (5.176) give a decomposition of the curvature velocities —Vij as a sum of elastic and plastic parts aijkiirikiy Vijy respectively. Let aijki x) = ajiki x) = akuj x), i,j,k,l = 1,2, and there exist two positive constants ci,C2 such that for all m = rriij ... [Pg.329]

Most engineering students are well aware that the first derivative of a continuous function is zero at a maximum or minimum of the function. Fewer recall that the sign of the second derivative signifies whether the stationary value determined by a zero first derivative is a maximum or a minimum. Even fewer are aware of what to do if the second derivative happens to be zero. Thus, this appendix is presented to put finding relative maxima and minima of a function on a firm foundation. [Pg.479]

A sigmoid (s-shaped) is a continuous function that has a derivative at all points and is a monotonically increasing function. Here 5,p is the transformed output asymptotic to 0 < 5/,p I and w,.p is the summed total of the inputs (- 00 < Ui p < -I- 00) for pattern p. Hence, when the neural network is presented with a set of input data, each neuron sums up all the inputs modified by the corresponding connection weights and applies the transfer function to the summed total. This process is repeated until the network outputs are obtained. [Pg.3]

Strict requirement and can be theoretically met only if we know the underlying continuous function that provides the values of the derivatives at the time points of a discrete representation. The availability, though, of such a continuous function is based on a series of ad hoc decisions on the character and properties of the functions, and if one prefers to avoid them, then one must accept a series of approximations for the evaluation of first and second derivatives. These approximations provide a sequence of representations with increasing abstraction, leading, ultimately, to qualitative descriptions of the state and trend as follows (Cheung and Stephanopoulos, 1990) ... [Pg.219]

Here, q> and j/ are continuous functions with continuous first and second derivatives, p is an observation point where the potential is determined, and q is an arbitrary point. [Pg.34]

Our task is to derive an explicit expression for the potential U proceeding from this equation. This means that we have to take the function U out of this integral. With this purpose in mind consider the limiting value of the second integral, when the radius of the spherical surface r tends to zero. Since both the potential and its derivatives are continuous functions inside the volume, we have... [Pg.35]

The behavior of the function U z) is shown in Fig. 1.15a. In the limiting case of surface masses the potential remains a continuous function, but its derivative, dUjdz, has a discontinuity at the plane z = 0, Fig. 1.15b. In deriving Equations (1.152 and 1.153) we used the fact that the potential is a continuous function at the layer boundaries otherwise the field would be infinitely large. [Pg.53]

The random-walk model of diffusion can also be applied to derive the shape of the penetration profile. A plot of the final position reached for each atom (provided the number of diffusing atoms, N, is large) can be approximated by a continuous function, the Gaussian or normal distribution curve2 with a form ... [Pg.214]

Consequently, it is permissible to equate the derivatives, as these are continuous functions,... [Pg.142]

In carrying out analytical or numerical optimization you will find it preferable and more convenient to work with continuous functions of one or more variables than with functions containing discontinuities. Functions having continuous derivatives are also preferred. Case A in Figure 4.1 shows a discontinuous function. Is case B also discontinuous ... [Pg.114]

I which f(V) is any continuous function of volume, e. Derive the expression... [Pg.152]

Application to Macromolecular Interactions. Chun describes how one can analyze the thermodynamics of a particular biological system as well as the thermal transition taking place. Briefly, it is necessary to extrapolate thermodynamic parameters over a broad temperature range. Enthalpy, entropy, and heat capacity terms are evaluated as partial derivatives of the Gibbs free energy function defined by Helmholtz-Kelvin s expression, assuming that the heat capacities integral is a continuous function. [Pg.366]

More recently, with the significant increases in computer power even on desktop PCs, methods for directly matching 3-D features of molecules have become more prevalent. Features here generally refer to various types of molecular fields, some such as electron density ( steric ) and electrostatic-potential fields are derived from fundamental physics (30,31) while others such as lipophilic potential fields (32) are constructed in an ad hoc manner. Molecular fields are typically represented as continuous functions. Discrete fields have also been used (33) albeit somewhat less frequently except in the case of the many CoMFA-based studies (34). [Pg.6]

In the following we derive an expression for without bothering about a physically valid core-valence separation, treating E " as if it were a continuous function of rt-The acceptable discrete solutions of E " are selected afterward. [Pg.27]

In addition to initial conditions, solutions to the Schrodinger equation must obey certain other constraints in form. They must be continuous functions of all of their spatial coordinates and must be single valued these properties allow VP P to be interpreted as a probability density (i.e., the probability of finding a particle at some position can not be multivalued nor can it be jerky or discontinuous). The derivative of the wavefunction must also be continuous except at points where the potential function undergoes an infinite jump (e.g., at the wall of an infinitely high and steep potential barrier). This condition relates to the fact that the momentum must be continuous except at infinitely steep potential barriers where the momentum undergoes a sudden reversal. [Pg.41]

Two major forms of the OCFE procedure are common and differ only in the trial functions used. One uses the Lagrangian functions and adds conditions to make the first derivatives continuous across the element boundaries, and the other uses Hermite polynomials, which automatically have continuous first derivatives between elements. Difficulties in the numerical integration of the resulting system of equations occur with the use of both types of trial functions, and personal preference must then dictate which is to be used. The final equations that need to be integrated after application of the OCFE method in the axial dimension to the reactor equations (radial collocation is performed using simple orthogonal collocation) can be expressed in the form... [Pg.153]

Local cubic interpolation results in a function whose derivative is not necessarily continuous at the grid points. With a non-local adjustment of the coefficients we can, however, achieve global differentiability up to the second derivatives. Such functions, still being cubic polynomials between each pair of grid points, are called cubic splines and offer a "stiffer" interpolation than the strictly local approach. [Pg.235]

The following proposition justifies the rehance on spherical harmonics in spherically symmetric problems involving the Laplacian. To state it succinctly, we introduce the vector space C2 C 2(R3) continuous functions whose first and second partial derivatives are all continuous. [Pg.365]

In an attempt to model the spectral functions of rare gas mixtures, Fig. 3.2, it was noted that a Gaussian function with exponential tails approximates the measurements reasonably well [75], about as well as the Lorentzian core with exponential tails. Two free parameters were chosen such that at the mending point a continuous function and a continuous derivative resulted the negative frequency wing was again chosen as that same curve, multiplied by the Boltzmann factor, to satisfy Eq. 3.18. Subsequent work retained the combination of a Lorentzian with an exponential wing and made use of a desymmetrization function [320],... [Pg.136]

With the knowledge that the pressure and each mole fraction are continuous functions of r and the temperature is independent of r, we can obtain the derivative... [Pg.382]


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See also in sourсe #XX -- [ Pg.22 , Pg.23 ]




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