Due to the prohibitive computational time required for even a single heuristic search under the MP criterion, we employed the parsimony ratchet method [65]; this approach was implemented by means of the program PAUPRAT [66] using 500 repetitions and randomly perturbing 25% of the characters for each re-weighting.
In order to reduce the prohibitive computational time, migration estimates were carried out on a proportional sub-sampling of each cluster.
For example, it is impossible to apply standard implementations such as LIBSVM [ 9] and SVM light[ 10], because it requires prohibitive computational time and the size of the kernel matrix for compound-protein pairs is too huge to construct explicitly in the memory.
However, some models, including detailed solute transport models, are further limited by prohibitive computation times.
A serious limitation of the compound-filling framework is that it is not suitable for predicting pathways for many compounds at a time owing to prohibitive computational cost.
One serious problem with pairwise SVMs is that the complexity of the 'training' phase scales with the square of the 'number of training ligands times the number of training proteins', leading to prohibitive computational difficulties for large-scale problems.
However, due to the mixed binary integer programming, it is prohibitive computational burden at CBS, which leads the increase of computation cost and allocation delay.
Both [9] and [10] equalized SC-FDMA without reference symbols but the equalizer was implemented in time domain making it unsuitable for channels with long impulse responses due to prohibitive computational complexity.
Direct time integration of full, nonlinear, finite element models can provide accurate results, but at a prohibitive computational expense.
However, simulation results show that the effort and computational times required for such a coupled simulation, in particular in a general three-dimensional (3D) case, could be prohibitive and unrealistic.
