We explore features of rupture dynamics that (1) lead to slip heterogeneity in earthquake ruptures and (2) maintain conditions that permit slip heterogeneity in subsequent events. Our 3-D finite-element simulations of magnitude 7 events on a vertical, planar strike-slip fault show that the conditions that lead to slip heterogeneity remain in place after large events when the initial shear stres...

We show that computing the lexicographically first four-coloring for planar graphs is ∆p2hard. This result optimally improves upon a result of Khuller and Vazirani who prove this problem NP-hard, and conclude that it is not self-reducible in the sense of Schnorr, assuming P 6= NP. We discuss this application to non-self-reducibility and provide a general related result. We also discuss when rai...

[1] We examine how frictional heating drives the evolution of temperature, strength, and fracture energy during earthquake slip. For small slip distances, heat and pore fluid are unable to escape the shearing fault core, and the behavior is well approximated by simple analytical models that neglect any transport. Following large slip distances, the finite width of the shear zone is small compar...

Abstract. We investigate spectral properties of a quantum particle confined to an infinite straight planar strip by imposing Robin boundary conditions with variable coupling. Assuming that the coupling function tends to a constant at infinity, we localize the essential spectrum and derive a sufficient condition which guarantees the existence of bound states. Further properties of the associated...

A number of planar deformation mechanisms, such as microtwinning, a[112] dislocation ribbon, and superlattice intrinsic and superlattice extrinsic stacking fault formation, can operate during the intermediate temperature deformation of nickle-based superalloys. The fundamental, rate-limiting processes controlling these deformation mechanisms are not fully understood. It has been recently postul...

Fault-tolerant motion of redundant manipulators can be obtained by joint velocity reconfiguration. For faulttolerant manipulators, it is beneficial to determine the configurations that can tolerate the locked-joint failures with a minimum relative joint velocity jump. This is because the manipulator can rapidly reconfigure itself to tolerate the fault. This paper uses the properties of conditio...

For a planar directed graph G, Postnikov’s boundary measurement map sends positive weight functions on the edges of G onto the appropriate totally nonnegative Grassmann cell. Assuming, without much loss of generality, that G is perfectly oriented, we establish an explicit formula for Postnikov’s map by expressing each Plücker coordinate as a ratio of two combinatorially defined polynomials in t...

The plasma wave acceleration of electron in the bubble regime is investigated in a new configuration containing a planar wiggler. The space-charge field of the laser-created ion channel can focuse and stabilize the electron trajectory to guide it toward the acceleration region. The high-gradient plasma wave field can resonantly accelerate the trapped electron to higher energies in the presence ...

The tsunami source of the 2016 Fukushima Earthquake, which was generated by a normal faulting earthquake mech‐ anism, is estimated by inverting the tsunami waveforms that were recorded by seven tide gauge stations and two wave gauge stations along the north Pacific coast of Japan. Two fault models based on different available moment tensor solutions were employed, and their locations were const...

This paper presents a new observer design methodology for a time varying actuator fault estimation. A new linear matrix inequality (LMI) design algorithm is developed to tackle the limitations (e.g. equality constraint and robustness problems) of the well known so called fast adaptive fault estimation observer (FAFE). The FAFE is capable of estimating a wide range of time-varying actuator fault...