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Results for “Locking”
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Small Signal Stability of Phase Locked Loop Based Current-Controlled Inverter in 100% Inverter-Based System
Not provided.
Phase-locked fiber interferometer with high frequency low voltage fiber-stretcher and application to optical field reconstruction.
Abstract not provided.
Generation and control of phase-locked Bessel beams with a persistent noninterfering region
We present, to the best of our knowledge, a novel method for the generation of multiple Bessel-like (Bessel–Gauss) beams with tilted wavefronts whose optical phases can be controlled independently. In the far field multiple field-free regions develop that are persistent to interference effects and the optical phase. The extent of these field-free regions can be controlled through the tilt angle of the wavefront with a theoretical maximum resolution of 0.1 mrad. Experimentally we employ a spatial light modulator, a lens, and an axicon, each suitable for narrow-band (continuous-wave) and broadband operation. Because of the simplicity in the optical elements, the number of noninterfering Bessel-like beams can be scaled on demand for applications that require multiple sources for coherent imaging or multiple intense beams over a controllable region with the added benefit of a field-free region for detection. Here, for reasons of clarity, we characterized two beams.
An Investigation of Multiple Phase-Locked Loop Control Methods for Nonlinear Force Appropriation Testing (Submission 10072).
Abstract not provided.
Continued Magnetron Injection Locking Studies
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Investigating Lock On in Gallium Nitride Photoconductive Solid State Switches.
Abstract not provided.
A 10GHz Low-Jitter Cryogenic Phase-Locked Loop (PLL) For Quantum Applications
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104Hz Linewidth, Self-injection Locked, Chip Scale NIR Laser
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Void and Helium Bubble Interactions with Dislocations in an fcc Stainless Steel Alloy: Anomalous Hardening and Void Cross-Slip Locking
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Breaking the Vendor Lock - Performance Portable Programming Through OpenMP as Target Independent Runtime Layer
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Switchable rocker arm
A rocker arm includes an outer arm defining a lock pin bore which is centered about a lock pin bore axis and an inner arm which selectively pivots relative to the outer arm about a pivot axis which is parallel to the lock pin bore axis. The inner arm includes a protrusion which defines an inner arm stop surface which is planar. A lock pin is disposed within the lock pin bore, the lock pin having a lock pin slot extending there into and also having a lock pin stop surface which is planar. The lock pin is displaced within the lock pin bore between a coupled position in which the lock pin stop surface is aligned with the inner arm stop surface and a decoupled position in which the lock pin slot is aligned with the protrusion.
Selectively adjustable interface assembly
A system includes a first component, a second component, a locking pin, and an interface assembly that is configured to selectively adjust a stiffness of a coupling interface between the first component and the second component. The interface assembly includes at least one support coupler secured to the first component. The support coupler(s) includes a main body, a first arm extending from a first side of the main body, a second arm extending from a second side of the main body, and a flange extending from the main body. The flange includes a locking pin hole that is configured to selectively receive the locking pin. The locking pin is selectively moveable between a retracted position in which the locking pin is out of the locking pin hole, and a deployed position in which the locking pin extends into the locking pin hole and a portion of the first component and locks the interface assembly to the first component.
Multiscale Models for Fibril Formation: Rare Events Methods, Microkinetic Models, and Population Balances
Amyloid fibrils are thought to grow by a two-step dock-lock mechanism. However, previous simulations of fibril formation (i) overlook the bi-molecular nature of the docking step and obtain rates with first-order units, or (ii) superimpose the docked and locked states when computing the potential of mean force for association and thereby muddle the docking and locking steps. Here, we developed a simple microkinetic model with separate locking and docking steps and with the appropriate concentration dependences for each step. We constructed a simple model comprised of chiral dumbbells that retains qualitative aspects of fibril formation. We used rare events methods to predict separate docking and locking rate constants for the model. The rate constants were embedded in the microkinetic model, with the microkinetic model embedded in a population balance model for “bottom-up” multiscale fibril growth rate predictions. These were compared to “top-down” results using simulation data with the same model and multiscale framework to obtain maximum likelihood estimates of the separate lock and dock rate constants. We used the same procedures to extract separate docking and locking rate constants from experimental fibril growth data. Our multiscale strategy, embedding rate theories, and kinetic models in conservation laws should help to extract docking and locking rate constants from experimental data or long molecular simulations with correct units and without compromising the molecular description.
Shapiro steps and stability of skyrmions interacting with alternating anisotropy under the influence of ac and dc drives
Here we use atomistic simulations to examine the sliding dynamics of a skyrmion in a two-dimensional system containing a periodic one-dimensional stripe pattern of variations between low and high values of the perpendicular magnetic anisotropy. The skyrmion changes in size as it crosses the interface between two anisotropy regions. On applying combined dc and ac driving in either parallel or perpendicular directions, we observe a wide variety of Shapiro steps, Shapiro spikes, and phase-locking phenomena. The phase-locked orbits have two-dimensional dynamics due to the gyrotropic or Magnus dynamics of the skyrmions and are distinct from the phase-locked orbits found for strictly overdamped systems. Along a given Shapiro step when the ac drive is perpendicular to the dc drive, the velocity parallel to the ac drive is locked while the velocity in the perpendicular direction increases with increasing drive to form Shapiro spikes. At the transition between adjacent Shapiro steps, the parallel velocity jumps up to the next step value, and the perpendicular velocity drops. The skyrmion Hall angle shows a series of spikes as a function of increasing dc drive, where the jumps correspond to the transition between different phase-locked steps. At high drives, the Shapiro steps and Shapiro spikes are lost. When both the ac and dc drives are parallel to the stripe periodicity direction, Shapiro steps appear, while if the dc drive is parallel to the stripe periodicity direction and the ac drive is perpendicular to the stripe periodicity, then there are only two locked phases, and the skyrmion motion consists of a combination of sliding along the interfaces between the two anisotropy values and jumping across the interfaces.