Like most NP-Complete problems, what is easy for a few small objects becomes impractical for larger more numerous objects.
Books require storage, and it quickly becomes impractical for publishers to keep low numbers of thousands of titles in their warehouses.
As workloads vary significantly according to current time of day, season, promotions and linking, it becomes impractical for some ecommerce sites to keep over-dimensioned infrastructures to accommodate the whole load.
However, all aforementioned works on BS cooperation assume full CSI at BSs, which becomes impractical for OFDMA systems due to their multiple carrier nature.
However, the expensive computing cost becomes impractical for disease studies involving genome scale markers and thousands of individuals.
The number of potential SNP combinations, however, increases exponentially and becomes impractical for our current GWAS sample size.
ODEs or PDEs mathematically represent signal transduction by introducing many parameters in the model, which becomes impractical for extremely large networks due to the increasing difficulty in parameter estimation [ 1].
When forces are applied to a linkage, these techniques need to compute the accelerations of all the joints and can become impractical for rapid prototyping of highly complex linkages with a large number of joints.
For volume mesh deformation driven by surface motion, the RBF system can become impractical for large meshes due to the large number of surface (control) points, and so a particularly effective data reduction scheme has been developed to vastly reduce the number of surface points used.
However, this way may become impractical for 3D cases as the memory requirement often exceeds the machine capacity.
