**Andrew M. Bradley**

**Software**:

My github.

hmmvp 1.3, a package to construct an H-matrix and compute matrix-vector products of the form B*x, B(rs,:)*x, and B(rs,cs)*x(cs). The package hmmvpex 0.1 contains practical usage examples.

dc3dm 0.3, a package to construct and apply an H-matrix approximation to the displacement-discontinuity method (DDM) linear operator relating quasistatic dislocation and traction components on a nonuniformly discretized rectangular fault in a homogeneous elastic half space. See this AGU 2013 poster for details. Movie of slow slip in a region with many small asperities.

kfgs 0.4, a Matlab package to compute the gradient of the log likelihood function from a Kalman filter.

hmmvp 0.16, the old version. It has certain Matlab-focused features that may be useful, but it's much slower than hmmvp 1.0+.

**Publications**:

Hannah, W. M., Bradley, A. M., Guba, O., Tang, Q., Golaz, J. C., & Wolfe, J. Separating Physics and Dynamics grids for Improved Computational Efficiency in Spectral Element Earth System Models. Journal of Advances in Modeling Earth Systems, 2021, doi:10.1029/2020MS002419. [pdf, online]

Guba, O., Taylor, M. A., Bradley, A. M., Bosler, P. A., & Steyer, A. A framework to evaluate IMEX schemes for atmospheric models. Geoscientific Model Development, 13(12), 2020, doi:10.5194/gmd-13-6467-2020. [online]

L. Bertagna, O. Guba, M. Taylor, J. Foucar, J. Larkin, A. M. Bradley, S. Rajamanickam, and A. Salinger. A Performance-Portable Nonhydrostatic Atmospheric Dycore for the Energy Exascale Earth System Model Running at Cloud-Resolving Resolutions, in SC20: International Conference for High Performance Computing, Networking, Storage and Analysis (SC), pp. 1304-1317, IEEE Computer Society, 2020, doi:10.1109/SC41405.2020.00096. [pdf, online, dycore, tridiag solver]

A. M. Bradley, P. A. Bosler, O. Guba, M. A. Taylor, G. A. Barnett, Communication-efficient property preservation in tracer transport, SIAM J. Sci. Comput., 41(3), 2019, doi:10.1137/18M1165414. [pdf, online, implementation]

P. A. Bosler, A. M. Bradley, M. A. Taylor, Conservative multimoment transport along characteristics for discontinuous Galerkin methods, SIAM J. Sci. Comput., 41(4), 2019, doi:10.1137/18M1165943. [pdf, online, spherical polygon intersection and quadrature implementation]

L. Bertagna, M. Deakin, O. Guba, D. Sunderland, A. M. Bradley, I. K. Tezaur, M. A. Taylor, A. G. Salinger, HOMMEXX 1.0: a performance-portable atmospheric dynamical core for the Energy Exascale Earth System Model, Geosci. Model Dev., 12, 12, 2019, doi:10.5194/gmd-12-1423-2019. [pdf, online]

Y. Q. Wong, P. Segall, A. M. Bradley, and K. Anderson, Constraining the magmatic system at Mount St. Helens (2004-2008) using Bayesian inversion with physics-based models including gas escape and crystallization, J. Geophys. Res., 122, 2017, doi:10.1002/2017JB014343. [pdf]

J. Maurer, P. Segall, and A. M. Bradley, Bounding the moment deficit rate on crustal faults using geodetic data: Methods. J. Geophys. Res. Solid Earth, 2017, doi:10.1002/2017JB014300 [pdf, online]

K. Dmitrieva, P. Segall, and A. M. Bradley, Effects of linear trends on estimation of noise in GNSS position time series, Geophys. J. Int., 208, 2017, doi:10.1093/gji/ggw391. [pdf]

K. Kim, T. B. Costa, M. Deveci, A. M. Bradley, S. D. Hammond, M. E. Guney, S. Knepper, S. Story, and S. Rajamanickam, Designing vector-friendly compact BLAS and LAPACK kernels, SC17, doi:https://doi.org/10.1145/3126908.3126941 [pdf]

A. M. Bradley, A hybrid multithreaded direct sparse triangular solver, Proc. SIAM CSC, 2016, doi:10.1137/1.9781611974690.ch2. [pdf, online, code]

A. Bardin, F. Primeau, K. Lindsay, A. M. Bradley, Evaluation of the accuracy of an offline seasonally-varying matrix transport model for simulating ideal age, Ocean Modelling, 105, 2016, doi:10.1016/j.ocemod.2016.07.003. [online]

A. M. Bradley, Software for efficient static dislocation-traction calculations in fault simulators, Seis. Res. Lett., 85(6), 2014, doi:10.1785/0220140092. [pdf, online]

P. Segall, A. L. Llenos, S.-H. Yun, A. M. Bradley, and E. M. Syracuse, Time-dependent dike propagation from joint inversion of seismicity and deformation data, J. Geophys. Res. Solid Earth, 118, 2013, doi:10.1002/2013JB010251. [pdf]

K. M. Johnson, D. R. Shelly, and A. M. Bradley, Simulations of tremor-related creep reveal a weak crustal root of the San Andreas Fault, Geophys. Res. Lett., 2013, doi:10.1002/grl.50216. [online]

P. Segall and A. M. Bradley. Slow-slip evolves into megathrust earthquakes in 2D numerical simulations, Geophys. Res. Lett., 39(18), 2012, doi:10.1029/2012GL052811. [pdf]

P. Segall and A. M. Bradley. The role of thermal pressurization and dilatancy in controlling the rate of fault slip, J. of Applied Mechanics, 79(3), 2012, doi:10.1115/1.4005896. [pdf]

N. M. Bartlow, S. Miyazaki, A. M. Bradley, and P. Segall, Space-time correlation of slip and tremor during the 2009 Cascadia slow slip event, Geophys. Res. Lett., 2011, doi:10.1029/2011GL048714. [pdf]

P. Segall, A. M. Rubin, A. M. Bradley, and J. R. Rice, Dilatant strengthening as a mechanism for slow slip events, J. Geophys. Res., 115, 2010, doi:10.1029/2010JB007449. [pdf]

A. M. Bradley and L. Wein, Space debris: Assessing risk and responsibility,
Adv. in Space Res. 43,
2009, doi:10.1016/j.asr.2009.02.006. [online;
code to run model. Figs. 3a,b have label errors: in 3a,
*Intact-Intact* should be switched
with *Cat. Intact-Fragment*; in 3b, *Noncat.* should be
switched with *Cat.*. Fig. 5 erroneously shows (solid
line) *steady-state*, rather than *maximum*, lifetime
risk; these differ only for compliance rate near 1:
see this version for
details. Longer technical report.]

**Reports**:

A. M. Bradley, H-Matrix and Block Error Tolerances. [arXiv]

A. M. Bradley and W. Murray, Matrix-Free Approximate Equilibration. [arXiv]

**Posters and other formats**:

E3SM newsletter article on atmosphere transport and grid remap work.

Overview of atmosphere tracer transport work.

AGU 2013 poster.

**Tutorials**:

A tutorial on the adjoint method.

A code-based tutorial on some numerical linear algebra operations in Matlab.

A code-based tutorial (with solutions) on elementary, but important, concepts concerning the stability and order of accuracy of ODE integration methods. This is appropriate for a one-session review in a science class, for example.

**Thesis**:

*Algorithms for the Equilibration of Matrices and Their Application to
Limited-Memory Quasi-Newton Methods*, Ph.D. Thesis, Stanford ICME, May
2010. [pdf; `ssbin`
and `snbin` from Chapter 2 (with
improvements)]

Last updated 13 June 2021.