Big Chemical Encyclopedia

Chemical substances, components, reactions, process design ...

Articles Figures Tables About

Equality-constrained conditions

V L is equal to the constrained derivatives for the problem, which should be zero at the solution to the problem. Also, these stationarity conditions very neatly provide the necessaiy conditions for optimality of an equality-constrained problem. [Pg.484]

Lichens are fascinating organisms with equally fascinating chemical compositions. Their ability to survive in harsh and constrained conditions is largely dependent upon their chemical diversity. This brief review illustrates lichens to be powerful sources of highly oxygenated aromatic compounds with diverse biological activities. Till June 2012, more than 1000 secondary... [Pg.257]

Iris type of constrained minimisation problem can be tackled using the method of Lagrange nultipliers. In this approach (see Section 1.10.5 for a brief introduction to Lagrange nultipliers) the derivative of the function to be minimised is added to the derivatives of he constraint(s) multiplied by a constant called a Lagrange multiplier. The sum is then et equal to zero. If the Lagrange multiplier for each of the orthonormality conditions is... [Pg.72]

In these cases there is no well defined notion of a looser constraint, the choice is then either to force those variables to be equal in x and y, or to find some path from their value to a constraint on another inter- or intrasituational variable and thus be able to show that their values in jc, y should obey some ordering based on these other constraints. This topic is the subject of current research, but is not limiting in the flowshop example, since no such constraints exist. Lastly, it is not enough to assert conditions on the state variables in x and y, since we have made no reference to the discrete space of alternatives that the two solutions admit. Our definition of equivalence and dominance constrains us to have the same set of possible completions. For equivalence relationships the previous statement requires that the partial solutions, x and y, contain the same set of alphabet symbols, and for dominance relations the symbols of JC have to be equal to, or a subset of those of y. Thus our sufficient theory can be informally stated as follows ... [Pg.301]

The specific explanation structure for the flowshop problem is given in Fig. 10. In the example we have assumed that the sufficient condition is satisfied by having all the end-times of x less than or equal to those of y. Thus the proof begins by selecting the appropriate variable set, and proceeds to prove that each variable is more loosely constrained in x than in y. The intersituational variables in the flowshop problem are the start-times of the next state. [Pg.320]

Now consider the imposition of inequality [g(x) < 0] and equality constraints 7i(x) = 0] in Fig. 3-55. Continuing the kinematic interpretation, the inequality constraints g(x) < 0 act as fences in the valley, and equality constraints h(x) = 0 act as "rails. Consider now a ball, constrained on a rail and within fences, to roll to its lowest point. This stationary point occurs when the normal forces exerted by the fences [- Vg(x )] and rails [- V/i(x )] on the ball are balanced by the force of gravity [— Vfix )]. This condition can be stated by the following Karush-Kuhn-Tucker (KKT) necessary conditions for constrained optimality ... [Pg.61]

The solution is of the type of Equation 3-51. To satisfy u x=o = Q, all the in Equation 3-51 must be zero (this is because not only collectively but also individually A sm(X x)+B cos(k x) must be zero). To satisfy u x=l = 0, must equal tm, where n = l, 2,. That is, = nn/L. This example shows why the boundary conditions must be zero for the Fourier series method, because otherwise cannot be constrained. Replacing B and into Equation 3-51 leads to... [Pg.211]

Alternatively, an auxiliary variable wk can be introduced, constrained to be dynamically equal to qk using a Lagrange multiplier that turns out to be the substituted variable pk. The constraint condition in this ingenious procedure is Xk = Pk wk = 0. The modified Lagrangian is... [Pg.15]

The conditions yielding the unconstrained maximum centerline deposition rate give a deposition uniformity of only about 25%. While this may well be acceptable for some fiber coating processes, there are likely applications for which it is not. We now consider the problem of maximizing the centerline deposition rate, subject to an additional constraint that the deposition uniformity satisfies some minimum requirement. Assuming that the required uniformity is better than that obtained in the unconstrained case, the constrained maximum centerline deposition rate should occur when the uniformity constraint is just marginally satisfied. This permits replacing the inequality constraint of a minimum uniformity by an equality constraint that is satisfied exactly. [Pg.197]

In summary, condition 1 gives a set of n algebraic equations, and conditions 2 and 3 give a set of m constraint equations. The inequality constraints are converted to equalities using h slack variables. A total of M + m constraint equations are solved for n variables and m Lagrange multipliers that must satisfy the constraint qualification. Condition 4 determines the value of the h slack variables. This theorem gives an indirect problem in which a set of algebraic equations is solved for the optimum of a constrained optimization problem. [Pg.2443]

To complete the calculation of C, we must know the temperature dependence of i5y, Vg, and most important, p. This can only be done by solving the self-consistency condition p = h(p), (6.13), in more detail. To reduce the number of free parameters, we use the viscosity data fitted by the parameters in Table II for the temperature dependence of Vy. For this reason, we limit our discussion to systems in which tj has been measured over a wide temperature range. The remaining parameters are then Oq, v, and K to describe/(c) andp, a,A,A, D, and in C. If we scale all volumes by vg taken equal to v , that leaves only v /vq and k = kvo as unknowns in f(v). The latter is constrained, since we know... [Pg.499]


See other pages where Equality-constrained conditions is mentioned: [Pg.277]    [Pg.67]    [Pg.148]    [Pg.56]    [Pg.64]    [Pg.97]    [Pg.297]    [Pg.181]    [Pg.465]    [Pg.245]    [Pg.157]    [Pg.127]    [Pg.68]    [Pg.178]    [Pg.148]    [Pg.76]    [Pg.235]    [Pg.143]    [Pg.121]    [Pg.222]    [Pg.263]    [Pg.4097]    [Pg.405]    [Pg.83]    [Pg.614]    [Pg.154]    [Pg.2443]    [Pg.365]    [Pg.222]    [Pg.127]    [Pg.70]    [Pg.267]    [Pg.22]    [Pg.188]    [Pg.514]   


SEARCH



Equal

Equaling

Equality

Equality-constrained

Equalization

© 2024 chempedia.info