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As worldwide landslides frequently result in enormous casualties and huge economic losses, new landslide monitoring technologies are urgently required to develop for preventing and mitigating landslide hazard. In this paper, a self‐powered, flexible, timbo‐like triboelectric force and bend sensor (TTEFBS) is proposed and implemented, with the aim of effectively monitoring landslides. The fabricated TTEFBS, based on a single‐electrode working mode, consists of a timbo‐like inner polydimethylsiloxane (PDMS) core coated with a carbon electrode and an outer silicon rubber tube. Owing to the novel structure and sensing mechanism, the TTEFBS achieves high sensitivities (5.20 V N−1 under pressing and 1.61 V rad−1 under bending), fast response/relaxation time (<6 ms), and long‐term stability/reliability (more than 40 000 cycles). Furthermore, a wireless and distributed monitoring system using an array of TTEFBSs is developed for systematically detecting rockfalls, deep‐seated landslides, and superficial landslides. Additionally, a zigzag‐structured triboelectric nanogenerator (Z‐TENG), characterized by an open‐circuit voltage of ≈2058 V and a short‐circuit current of ≈154 µA, is successfully fabricated for scavenging energy from moving cars to provide power in wild environments, thereby forming a self‐powered monitoring system. This work may further inspire rapid progress of TENG in applications of wireless, distributed sensing, and environmental/infrastructure monitoring.

We study gravitational waves emitted by a binary system of non-spinning bodies in a quasi-circular inspiral within the framework of Einstein-aether theory. In particular, we compute explicitly and analytically the expressions for the time-domain and frequency-domain waveforms, gravitational wave polarizations, and response functions for both ground-and space-based detectors in the post-Newtonian approximation. We find that, when going beyond leading-order in the post-Newtonian approximation, the non-Einsteinian polarization modes contain terms that depend on both the first and the second harmonics of the orbital phase. We also calculate analytically the corresponding parameterized post-Einsteinian parameters, generalizing the existing framework to allow for different propagation speeds among scalar, vector and tensor modes, without assumptions about the magnitude of its coupling parameters, and meanwhile allowing the binary system to have relative motions with respect to the aether field. Such results allow for the easy construction of Einstein-aether templates that could be used in Bayesian tests of General Relativity in the future. * Anzhong Wang@baylor.edu; Corresponding Author 1 Recently, various GWs have been detected after LIGO/Virgo resumed operations on April 1, 2019, possibly including the coalescence of a neutron-star (NS)/BH binary. The details of these detections have not yet been released [3].

We calculate the gravitational waveform radiated from spinning black holes (BHs) binary in dynamical Chern-Simons (dCS) gravity. The equation of motion (EOM) of the spinning binary BHs is derived based on the modified Mathisson-Papapetrou-Dixon equation for the spin-aligned circular orbits. The leading-order effects induced by the dCS theory contain spin-spin interaction and monopole-quadrupole interaction, which influences both the EOM of the binary system and corresponding gravitational waveform at the second post-Newtonian (PN) order (i.e., 2PN order). After reporting the waveforms, we investigate the polarization modes of gravitational waves (GWs) in dCS theory. None of the extra modes appears in this theory up to the considered PN order. Moreover, since the time scale of the binary merger is much smaller than that of the cosmological expansion, the parity-violating effect of the dCS theory does not appear in the process of GW generation. However, during the process of GW propagation, amplitude birefringence, a typical parity-violating effect, makes plus and cross modes convert to each other, which modifies the gravitational waveform at 1.5PN order.

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Considering a thermal state of the dual CFT with a uniform deformation by a scalar operator, we study a holographic renormalization group flow at nonzero temperature in the bulk described by the Einstein-scalar field theory with the self-interaction term λφ 4 in asymptotic anti-de Sitter spacetime. We show that the holographic flow with the self-interaction term could run smoothly through the event horizon of a black hole and deform the Schwarzschild singularity to a Kasner universe at late times. Furthermore, we also study the effect of the scalar self-interaction on the deformed near-singularity Kasner exponents and the relationship between entanglement velocity and Kasner singularity exponents at late times.

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