Initially, the original rock mass rating (RMR) and quality (Q) systems were used for rock mass characterization, but difficulties were experienced in determining a number of input parameters required, particularly by the RMR system.
Limitations on morphological characterization, including difficulties concerning the definition and validation of neutral traits, experimental costs, evaluation time and genotype × environment interaction are widely discussed in germplasm characterization studies [ 30, 31].
Another disadvantage of using these indirect methods for variant characterization is the difficulties encountered to compare datasets generated in different laboratories, or in the same laboratory but at different times.
Its chemical formula and crystal structure have been the subject of considerable debate due to difficulties in characterization caused by its small particle size (<10 nm).
This study demonstrates that PAI, in conjugation with conventional US, provides opportunities to resolve the difficulties in characterization and therapy of inflammatory arthritis.
Results showed that even a relatively simple layering with less than an order magnitude difference in permeability leads to difficulty in characterization and remediation using flushing technologies.
This is partially due to the difficulty of characterization of non-DA neurons in the VTA because of the lack of a clear boundary between the VTA and surrounding nuclei.
These pitfalls are most often due to difficulty in characterization of nodes that have intermediate levels of uptake of the contrast rather than complete uptake (i.e. a black node) or non-uptake (i.e. a white node).
However, gene and genome duplications pose difficulties for functional characterization and translational research.
The results demonstrate that difficulties in the characterization of the pH, one of the most important parameters for drug delivery and polymer degradation, can be overcome by spectral spatial e.p.r.i.
