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Heuristic algorithms

Examples of learning mechanisms are neural networks and ant algorithms. Heuristics remains a reliable approach for the solution of practical instances of hard combinatorial problem such as the vehicle routing problem (Langevin and Riopel 2005). [Pg.764]

Definition 3-7 Algorithmic learning is performed by the sole execution of a learning algorithm. Heuristic learning is at least partially based on heuristics. [Pg.37]

Keywords Traveling Salesman Problem, Nature-based Algorithms, Heuristic Algorithms, Ant Colony Optimization Algorithms. [Pg.163]

The algorithm may calculate an increase in Qnmin and Qcmin- This means that the match is transferring heat across the pinch or that there is some feature of the design that will cause cross-pinch heat transfer if the design was completed. If the match is not transferring heat across the pinch directly, then the increase in utility will result from the match being too big as a result of the tick-off heuristic. [Pg.387]

The optimization of the backtracking algorithm usually consists of an application of several heuristics which reduce the number of candidate atoms for mapping from Gq to Gj. These heuristics are based on local properties of the atoms such as atom types, number of bonds, bond orders, and ring membership. According to these properties the atoms in Gq and Gj are separated into different classes. This step is known in the literature as partitioning [13]. Table 6.1 illustrates the process of partitioning. [Pg.301]

The first is a network that has minimum area but a maximum number of exchangers as proposed by the algorithmic—evolutionary approach (10). The algorithmic part of this method is the development of a minimum area network. The evolutionary part employs a set of rules to modify systematically the initial network. The three rules presented ate heuristic in nature and seek to combine exchangers and stream spHts to reduce network cost. The problem of reducing stream spHts appears difficult to researchers. [Pg.525]

The number of neurons to be used in the input/output layer are based on the number of input/output variables to be considered in the model. However, no algorithms are available for selecting a network structure or the number of hidden nodes. Zurada [16] has discussed several heuristic based techniques for this purpose. One hidden layer is more than sufficient for most problems. The number of neurons in the hidden layer neuron was selected by a trial-and-error procedure by monitoring the sum-of-squared error progression of the validation data set used during training. Details about this proce-... [Pg.3]

This index is employed by both the k-means (MacQueen, 1967) and the isodata algorithms (Ball and Hall, 1965), which partition a set of data into k clusters. With the A -means algorithm, the number of clusters are prespecified, while the isodata algorithm uses various heuristics to identify an unconstrained number of clusters. [Pg.29]

The algorithm originally proposed by Moody and Darken (1989) uses >means clustering to determine the centers of the clusters. The hypersphere around each cluster center is then determined to ensure sufficient overlap between the clusters for a smooth fit by criteria such as the P-nearest neighbor heuristic,... [Pg.29]

This is especially true for the pharmaceutical and the chemical industry where a great range of details have to be taken into account. To here successfully plan and optimize large supply chain scenarios it needs a specifically sophisticated combination of algorithms and heuristics [15,16, 29, 30]. [Pg.59]

Goldberg, A. and Radzik, T. (1993) A heuristic improvement of the bellman-ford algorithm. AMLETS Appl Math Lett, 6, 3-6. [Pg.90]

Since the program (DEP) represents a mixed-integer linear program (MILP), it can be solved by commercially available state-of-the-art MILP solvers like CPLEX [3] or XPRESS-MP [4], These solvers are based on implementations of modem branch-and-bound search algorithms with cuts and heuristics. [Pg.198]


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Heuristics

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