peclet : peclet number (negative means no Brownian force)
length : unit of the length scale [nm]
BD-seed : seed for Brownian force random number generator
n-cheb-minv : number of Chebyshev coefficients for M^{-1}
n-cheb-lub : number of Chebyshev coefficients for L
(if zero is given, use Cholesky decomposition)
BD-scheme : Brownian dynamics time integration scheme
"mid-point" The mid-point algorithm.
"BanchioBrady03" Banchio and Brady (2003).
"BallMelrose97" Ball and Melrose (1997).
"JendrejackEtal00" Jendrejack et al (2000).
"semi-implicit-PC" semi-implicit predictor-corrector.
"SI-connector" semi-implicit for connector vectors.
BB-n : step parameter for Banchio-Brady03 algorithm.
BD-nl-solver : nonlinear solver for implicit schemes
"GSL" GSL multiroot solver
"NITSOL" Newton-GMRES solver by Pernice and Walker (1998)
"fastSI" fast semi-implicit solver (only for "SI-connector")
* dt-ajustment parameters for Brownian dynamics
NOTE: if rmin is defined by non-zero, the process is skipped.
BD-rmin : overlap-param for dt-adjustment process in BD.
the condition is (r2 < rmin * a2).
dt-lim : lower bound to shrink dt to prevent overlaps.
set equal to "dt" if you don't want to adjust "dt"
but just reject it.
