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Minimum condition necessary conditions

The manufacture of sterile pharmaceuticals can only be performed in locations especially designed for this purpose, which in addition comply with the minimum conditions necessary to perform ... [Pg.344]

Consequently, in the system which satisfies the minimum conditions necessary for the realization of the ultimately stable state Dy — >, all the derivatives vanish which contain either the force Xk or the coordinates x, occurring in the stability coefficient (9Xk/9xk)xi... [Pg.110]

The coefficients Cj and Q are chosen so that the energy of this linear combination is a minimum, a necessary condition for which is that... [Pg.136]

These are only necessary conditions, as point ti may be a minimum, maximum, or saddle point. [Pg.484]

We now regard the experimental data as fixed and treat the model parameters as the variables. The goal is to choose C, w, n, and r such that > Q achieves its minimum possible value. A necessary condition for to be a minimum is that... [Pg.256]

The necessary conditions for k to be the optimal parameter values corresponding to a minimum of the augmented objective function SLo(k,a)) are given by Edgar and Himmelblau (1988) and Gill et al. (1981) and are briefly presented here. [Pg.166]

Examine the second term on the right-hand side of Equation (4.4) VTf(x ) Ax. Because Ax is arbitrary and can have both plus and minus values for its elements, we must insist that V/ (x ) = 0. Otherwise the resulting term added to/(x ) would violate Equation (4.5) for a minimum, or Equation (4.6) for a maximum. Hence, a necessary condition for a minimum or maximum of /(x) is that the gradient of/(x) vanishes at x ... [Pg.137]

With the second term on the right-hand side of Equation (4.4) forced to be zero, we next examine the third term (Axr) V2/(x )Ax. This term establishes the character of the stationary point (minimum, maximum, or saddle point). In Figure 4.17b, A and B are minima and C is a saddle point. Note how movement along one of the perpendicular search directions (dashed lines) from point C increases fix), whereas movement in the other direction decreases/(x). Thus, satisfaction of the necessary conditions does not guarantee a minimum or maximum. [Pg.137]

Recall that the first-order necessary condition for a local minimum is fix) = 0. Consequently, you can solve the equation/ ( ) = 0 by Newton s method to get... [Pg.158]

Let x be a local minimum or maximum for the problem (8.15), and assume that the constraint gradients Vhj(x ),j — 1,m, are linearly independent. Then there exists a vector of Lagrange multipliers A = (Af,..., A ) such that (x A ) satisfies the first-order necessary conditions (8.17)-(8.18). [Pg.271]

Examples illustrating what can go wrong if the constraint gradients are dependent at x can be found in Luenberger (1984). It is important to remember that all local maxima and minima of an NLP satisfy the first-order necessary conditions if the constraint gradients at each such optimum are independent. Also, because these conditions are necessary but not, in general, sufficient, a solution of Equations (8.17)-(8.18) need not be a minimum or a maximum at all. It can be a saddle or inflection point. This is exactly what happens in the unconstrained case, where there are no constraint functions hj = 0. Then conditions (8.17)-(8.18) become... [Pg.271]

The Kuhn-Tucker necessary conditions are satisfied at any local minimum or maximum and at saddle points. If (x, A, u ) is a Kuhn-Tucker point for the problem (8.25)-(8.26), and the second-order sufficiency conditions are satisfied at that point, optimality is guaranteed. The second order optimality conditions involve the matrix of second partial derivatives with respect to x (the Hessian matrix of the... [Pg.281]

Because — 2y is negative for all nonzero vectors in the set T, the second-order necessary condition is not satisfied, so (0, 0) is not a local minimum. [Pg.283]

Analytical solution. We set up the necessary conditions using calculus and also test to ensure that the extremum found is indeed a minimum. [Pg.465]

These give the necessary conditions for L to be minimum. The solution of the previous problem is... [Pg.119]

The achievement of various kinds of performance goiais is better discussed by assuming that the column is operated at the minimum pressure, a condition which is necessary in practice when the inlet pressure is in the hectobar range, that is, AP > 100 atm. This problem is titated in the next section. [Pg.188]

From the above, one can elicit that autopoiesis is not a necessary and sufficient condition for life. It is a necessary condition, but then it takes cognition, at least in the simplest stage, to arrive at the process of life. The union of autopoiesis and the most elementary form of cognition is the minimum that is needed for life. [Pg.171]

Now, it is useful to keep in mind our objective. The variational principle instructs us that as we get closer and closer to the true one-electron ground-state wave function, we will obtain lower and lower energies from our guess. Thus, once wc have selected a basis set, we would like to choose the coefficients a, so as to minimize the energy for all possible linear combinations of our basis functions. From calculus, we know that a necessary condition for a function (i.e., the energy) to be at its minimum is that its derivatives with respect to all of its free variables (i.e., the coefficients a,) are zero. Notationally, that is... [Pg.114]

From (8) the estimate zn < Tn z0 immediately follows, in which the quantity Tn depends on the parameters and rj2 Roughly speaking, a proper choice of such parameters is stipulated by the minimum condition for the norm Tn in connection with a minimal number of the necessary iterations. To be more specific, when making a substantiated choice, we have at our disposal two collections of parameters Ti t21 ... [Pg.714]


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See also in sourсe #XX -- [ Pg.366 , Pg.368 , Pg.369 ]




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