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Optimization methods, deterministic

We start with continuous variable optimization and consider in the next section the solution of NLP problems with differentiable objective and constraint functions. If only local solutions are required for the NLP problem, then very efficient large-scale methods can be considered. This is followed by methods that are not based on local optimality criteria we consider direct search optimization methods that do not require derivatives as well as deterministic global optimization methods. Following this, we consider the solution of mixed integer problems and outline the main characteristics of algorithms for their solution. Finally, we conclude with a discussion of optimization modeling software and its implementation on engineering models. [Pg.60]

II with a new chapter (for the second edition) on global optimization methods, such as tabu search, simulated annealing, and genetic algorithms. Only deterministic optimization problems are treated throughout the book because lack of space precludes discussing stochastic variables, constraints, and coefficients. [Pg.663]

Of course, besides stochastic global optimization methods, there are also many deterministic methods [138-140]. Typical applications of these to clusters have so far been possible only for trivially small clusters, for example, LJ7 in Ref. [ 141 ] or LJ 13 in Ref. [ 142]. Clearly, this is no match at all for the stochastic methods that have now reached LJ309 in the CSA work of Lee et al. [133]. [Pg.47]

The major problem with structured models is their large number of parameters, which makes the estimation procedure a difficult task. The use of deterministic optimization methods, such as QN, to estimate a large number of parameters (in the studied case 43) usually leads to lack of convergence. On the other hand, GAs are well suited to large-scale problems but have the drawback of slow convergence. In this work, it is proposed an estimation methodology in four steps that can be used always that a re-estimation of parameters is necessary. [Pg.673]

The optimization methods introduced in (Huseby Haavardsson, 2009) and (Haavardsson et al., 2008) always assumes that the PPR-functions are completely known. Thus, the search is carried out in a fully deterministic setting. In real life apphcations, however, this will rarely be the case. Thus, a natural question to ask is how well a deterministically optimal production strategy performs in the presence of uncertainty. [Pg.414]

Even when the production profiles are uncertain, it is possible to apply optimization methods similar to those used in the deterministic case. A very simple approach to this problem is to simply replace the uncertain quantities in the model by point estimates, and then solve the optimization problem deterministically using these estimates. If the imcertainty is not too substantial, this approach may produce reasonably good results. On the other hand if the optimal solution varies a lot even for small changes in the parameter values, this approach may not produce a robust solution. [Pg.414]

GA is a new parallel optimization search method which is different from the traditional optimization methods in the field of application. Goldberg [114] summarized the differences between GA and traditional optimization method as follows GA operates the code of the solution set not the solution set itself GA searches from one population, not a single solution GA uses the compensation information (fitness function), not derivatives or other complementation knowledge GA uses methods of probability, not the deterministic rule of state transition. [Pg.30]

New methods for global optimization are continually generating interest in chemical engineering. Recent advances in deterministic global optimization methods for the enclosure of all solutions of non linearly constrained problem allow us to consider a wide range of chemical engineering optimisation problems Floudas (1999). [Pg.23]

There are multiple approaches that one could take to examine the literature on operability analysis, but the method taken in this chapter is to divide the body of research into steady-state and dynamic classifications. Each of these classifications further consists of different approaches that utilize linear and non-linear analysis, statistical models versus deterministic models, open loop versus closed loop analysis, and optimization methods versus less numerically intense methods. These subcategories are incorporated into the two main divisions of steady-state and dynamic analysis. The most complete picture of the existing research is best gained by examining the body of literature in this manner. [Pg.98]

The global optimization method aBB deterministically locates the global minimum solution of (1) based on the refinement of converging lower and upper bounds. The lower bounds are obtained by the solution of (15), which is formulated as a convex programming problem. Upper bounds are based on the solution of (1) using local minimization techniques. [Pg.276]

The problem posed in Eq. (51) involves the solution of a system of nonlinear equations. The identification of all multiple global solutions requires the use of a deterministic global optimization method, as outlined in Section n.B. The application of this method to protein systems will be described fully in Section IV.B. [Pg.318]

In molecular structure space, the Hamiltonian variables are associated with the atom types and their spatial arrangement.Different stochastic and deterministic optimization algorithms have been adapted to work in inverse molecular design methods. The choice of an optimization method depends on how the particular Hamiltonian, linking structure and property, is varied during a search (i.e. depends on the set of Hamiltonian parameters/variables that are varied). [Pg.2]

Floudas CA (2000) Deterministic Global Optimization Theory, Methods and Applications, Kluwer Academic Publishers. [Pg.15]

The problem of multivariable optimization is illustrated in Figure 3.4. Search methods used for multivariable optimization can be classified as deterministic and stochastic. [Pg.38]

Bias is allowed between laboratories when constant and deterministic. For any method of optimization we must consider the requirements for precision and bias, specificity, and MDL. [Pg.483]

The use of uncertainty conscious schedulers - schedulers which consider the uncertain parameters already at the scheduling stage - have the potential to lead to a significant increase in the profit compared to deterministic methods. However, the resulting optimization problems are usually of large scale and it is difficult to solve them within the short period of time available in a real-time environment. [Pg.185]

So far, only techniques, starting from some initial point and searching locally for an optimum, have been discussed. However, most optimization problems of interest will have the complication of multiple local optima. Stochastic search procedures (cf Section 4.4.4.1) attempt to overcome this problem. Deterministic approaches have to rely on rigorous sampling techniques for the initial configuration and repeated application of the local search method to reliably provide solutions that are reasonably close to globally optimal solutions. [Pg.70]


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