Abstract Extreme-mass-ratio inspirals (EMRIs) are important targets for future space-borne gravitational-wave (GW) detectors, such as the Laser Interferometer Space Antenna (LISA). Recent works suggest that EMRIs may reside in a population of newly discovered X-ray transients called “quasiperiodic eruptions” (QPEs). Here, we follow this scenario and investigate whether LISA could detect QPEs. W...

Polydomain liquid crystalline (nematic) elastomers have highly unusual mechanical properties, dominated by the dramatically nonlinear stress–strain response that reflects stress-induced evolution of domain patterns. Here, we study classical Hertz indentation problem in such a material. Experimentally, find polydomain nematic display smaller exponent than 3/2 load vs. depth response. This is puz...

This article reviews the beginnings of the NICHD intramural clinical research program; it focuses on three men, Roy Hertz, Mort Lipsett, and Griff Ross, who were instrumental in providing the intramural research program with the vision and character seen today.

Abstract The paper focuses on local phenomena modelling in the ball-and-socket pivot of tilting pad journal bearings. It provides an in-depth analysis influence nonlinear normal force and friction forces generated dynamic behaviour bearing. Contemporary works often employ Hertz theory, which is valid for non-conformal contacts. This research, however, utilises a conformal sphere-to-sphere conta...

The author demonstrates a stable Lagrangian solid modeling method, tracking the interactions of solid mass particles rather than using a meshed grid. This numerical method avoids the problem of tensile instability often seen with smooth particle applied mechanics by having the solid particles apply stresses expected with Hooke’s law, as opposed to using a smoothing function for neighboring soli...

Computing the inverse dynamics of a robot arm is an active area of research in the control literature. We apply a backpropagation network to this problem and measure its performance on the first 2 joints of the CMU Direct-Drive Arm II for a family of "pick-and-place" trajectories. Trained on a random sample of actual trajectories, the network is shown to generalize with a root mean square error...

The theory of the tight span, a cell complex that can be associated to every metric D, offers a unifying view on existing approaches for analyzing distance data, in particular for decomposing a metric D into a sum of simpler metrics as well as for representing it by certain specific edge-weighted graphs, often referred to as realizations of D. Many of these approaches involve the explicit or im...

A model is developed which explains the collective plasma phenomena associated with the extended Franck-Hertz experiment described in an earlier paper by Nicoletopoulos [Eur. J. Phys. 23, 533 (2002)]. The particular focus is on the formation of the free steady-state monotonic double layer. The approach used is a Bernstein-Greene-Kruskal theory in which one postulates the space potential and a s...

Hertz contact theory has been widely used for the determination of cell elasticity based on AFM indentation experiments. In light of the adhesive contact between AFM tip and cell, this study applied Johnson-Kendall-Roberts (JKR) model to fit the indentation force-displacement (F-D) curves reported previously. A MIN6 cell has been modeled as first a sphere and then a flattened cell with differen...