When a plane-wave basis set is used (as opposed to the more familiar atom-centred basis sets), the electron density is (indirectly) described as a Fourier series, automatically rendering the electron density three-dimensional periodic: an obvious choice for crystals.
To form monolayer polymer sheet with periodic structural order, the choice of monomer is critical.
The choice of periodic boundary conditions is motivated by the difficulty in the study of the PBVP textstylebegin{cases} D_{0^^{beta} phi_{p}(D_{0^^{alpha}x t)) )=h(t),quad tin [0,T], x 0)=x(T),quadquad D_{0^^{alpha}x 0)=D_{0^^{alpha}x(T).
Most phase-change materials contain at least one element from group 6 of the periodic table, and the choice of available materials can be further widened by doping these materials [104 107].
The treatment of choice involves periodic doctor-administered injections of medication directly into the affected eye(s).
We need, as Ellen Hodgson Brown suggests, a new debtor's bill of rights; otherwise we face the continuing choice between periodic economic collapse or rising inequalities and social chaos.
D.F., aged 40, talked about how she is using the "rhythm method" (or periodic abstinence) as her choice of birth control.
Note that other choices like periodic B-splines, periodic wavelets, oder calender month dummies would be possible as well.
Although a couple may make a private choice to use periodic abstinence, just as they might buy condoms, most modern methods of periodic abstinence require careful training by a trained counsellor.
Second, a natural question arising regards the choice of the periodic genes in the SCC as starting point for the shortest paths connecting to other periodic genes outside the SCC.
