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Cost function term

In an analogous approach, the additional cost function terms are now determined. In addition to manufacturing costs, percentage increases for general management, sales and profit and risk to determine the net offer price have to be added. The following applies ... [Pg.643]

It is possible to construct a Cl wave function starting with an MCSCF calculation rather than starting with a HF wave function. This starting wave function is called the reference state. These calculations are called multi-reference conhguration interaction (MRCI) calculations. There are more Cl determinants in this type of calculation than in a conventional Cl. This type of calculation can be very costly in terms of computing resources, but can give an optimal amount of correlation for some problems. [Pg.25]

If the matrix A is positive definite, i.e. it is symmetric and has positive eigenvalues, the solution of the linear equation system is equivalent to the minimization of the bilinear form given in Eq. (64). One of the best established methods for the solution of minimization problems is the method of steepest descent. The term steepest descent alludes to a picture where the cost function F is visualized as a land-... [Pg.166]

The take home message of this section is that local and GGA functionals perform more or less similarly for IR and Raman intensities, whereas the hybrid ones offer a significant improvement, yielding results comparable or even better than MP2 for significantly less computational cost. In terms of basis sets, at least double-zeta sets augmented by flexible polarization and diffuse functions are needed. The POL basis set seems to offer a particularly good price/performance ratio. [Pg.211]

In the formulation above, the discrete optimization on the number of compressors has been transformed into a continuous optimization on suction and delivery pressures. This transformation was made possible by the form of the compressor cost function which vanishes when pd = ps. However, if the compressor costs include a fixed capital outlay, i.e., the cost function is a linear function of horsepower with a nonzero constant term, then a branch and bound procedure must be used in conjunction with the GRG method. [Pg.183]

The occurrence of the set-up procedure in period i is denoted by the binary variable Wi (0 = no, 1 = yes). The production costs per batch are denoted by p = 1.0 and the cost for a set-up is y = 3.0. Demands di that are satisfied in the same period as requested result in a regular sale Mi with a full revenue of a = 2.0 per unit of product. Demands that are satisfied with a tardiness of one period result in a late sale Mf with a reduced revenue of aL = 1.5 per unit. Demands which are not satisfied in the same or in the next period result in a deficit Bf with a penalty of a = 0.5 per unit. The surplus production of each period is stored and can be sold later. The amount of batches stored at the end of a period is denoted by Mf and the storage costs are a+ =0.1 per unit. The objective is to maximize the profit over a horizon of H periods. The cost function P contains terms for sales revenues, penalties, production costs, and storage costs. For technical reasons, the model is reformulated as a minimization problem ... [Pg.187]

Step 5. Look at the total cost function, Equation (c). Observe that the cost function includes a constant term, K3Q. If the total cost function is differentiated, the term K3Q vanishes and thus K3 does not enter into the determination of the optimal value for D. K3, however, contributes to the total cost. [Pg.22]

Objective function. The objective function for the reactor optimization is based on the difference between the value of the product gas (heating value and ammonia value) and the value of the feed gas (as a source of heat only) less the amortization of reactor capital costs. Other operating costs are omitted. As shown in Murase et al., the final consolidation of the objective function terms (corrected here) is... [Pg.490]

In designing or improving a waveform library certain questions arise. Firstly it is important to establish the measure of effectiveness (MoE) for individual waveforms (cost function) and then to extend this to an MoE for the library. If a particular set of waveforms is added, will this improve the library in these terms and, on the other hand, how much will removing some waveforms reduce the utility of the library It is the purpose of this chapter to develop an information theoretic framework... [Pg.277]

An alternative chemical product classification in terms of volume produced, cost, function of product and processing needs has been discussed in chapter 1. [Pg.475]

For a trait to be selected for, or not selected against, its benefits should increase fitness more than its costs reduce fitness, on average. A growing literature on the evolution of chemical defenses suggests that decreased susceptibility to consumers can be achieved only by diverting materials and energy from other functions.7 19 65-68 While there are several theoretical reasons to believe that defenses are costly in terms of trade-offs, this common assumption is supported by litde direct evidence.65 However, there is much circumstantial evidence that supports the idea that the production, maintenance, transport, and storage of secondary metabolites have associated costs. [Pg.331]

The system identification step in the core-box modeling framework has two major sub-steps parameter estimation and model quality analysis. The parameter estimation step is usually solved as an optimization problem that minimizes a cost function that depends on the model s parameters. One choice of cost function is the sum of squares of the residuals, Si(t p) = yi(t) — yl(t p). However, one usually needs to put different weights, up (t), on the different samples, and additional information that is not part of the time-series is often added as extra terms k(p). These extra terms are large if the extra information is violated by the model, and small otherwise. A general least-squares cost function, Vp(p), is thus of the form... [Pg.126]

Rawlings and co-workers proposed to carry out parameter estimation using Newton s method, where the gradient can be cast in terms of the sensitivity of the mean (Haseltine, 2005). Estimation of one parameter in kinetic, well-mixed models showed that convergence was attained within a few iterations. As expected, the parameter values fluctuate around some average values once convergence has been reached. Finally, since control problems can also be formulated as minimization of a cost function over a control horizon, it was also suggested to use Newton s method with relatively smooth sensitivities to accomplish this task. The proposed method results in short computational times, and if local optimization is desired, it could be very useful. [Pg.52]

All of these direct NOE penalty functions have several features in common. First, they are all, in principle, more correct than refinement against calculated distances. Unfortunately, they vary from moderately to extremely costly in terms of CPU time. Each implementation also raises the question of the nature of the spectral density function used to model the molecule s motions. In each case, except that of Baleja et al.,66 isotropic motion was assumed, although all the methods could be readily adapted to use more elaborate spectral density functions. As experience with these methods accumulates, it should become clear when the extra computational time is worth investing and what the effects of different motional models are. [Pg.157]

For closest-packed oxides, a Pannetier-type cost function [58] is more robust and faster to evaluate than the lattice energy as defined earlier. Here, the bond valence model [59] is used to calculate the charge on the ions and the discrepancy with the expected value is used to measure the quality of the structure. With an additional term, the discrepancy in the expected and calculated coordination numbers, the cost function becomes... [Pg.108]

It is desired to find non-negative values of xu x2, and xa that minimize this function and at the same time satisfy the constraints of the previous example. We shall begin with the basis xa, u1( and u2, which was shown to be feasible in the last example. At the end of the last example these variables were expressed in terms of the nonbasic variables Xi and x2) and so it only remains to express the new cost function in terms of these variables. Eliminating xa with the second line of the final table there gives... [Pg.322]

Ordinarily we would introduce artificial variables and begin using the simplex method to reduce the sum of these variables to zero. However, in order to save space, as well as to demonstrate the effect of the quadratic term in the cost function, we shall start with the basis which was optimal in the linear case just solved. This basis, namely x2, x3, and u2, will of course be feasible for the three original constraints. If we filled out the basis by using vly v2, and v2, the basis would be feasible and there would be no artificial variables. Although at first glance it would appear that the basis x2) x3l u2, vlt v2 and v3 is optimal, this is not true because of the complementary slackness condition, which prohibits having both x2 and v2, or both x3 and v3, in the same basis. [Pg.327]


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