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Showing 1 to 17 of 17 for “"Nutation"”.
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Nutation in the spinning SPHERES spacecraft and fluid slosh
… in predicting the likelihood of rapid nutation growth due to onboard liquids. Solely analytical methods of prediction are mainly unsuccessful and physical tests to gather slosh data have only been done for a few specific spacecraft. Data from past spacecraft is subject to a number …
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Parameter Estimation of Spacecraft Fuel Slosh Using Pendulum Analogs
<p>The nutation (wobble) of a spinning spacecraft in the presence of energy dissipation is a well-known problem in dynamics and is of particular concern for space missions. Its rate of growth is characterized by the Nutation Time Constant (NTC). For analytical prediction of the NTC, fuel slosh is …
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Implications for Microtubule Mediated Ethylene Effects in Pea Stem Sections
… of swelling, hook curvature, and horizontal nutation. Electron microscopy shows that microtubules are reoriented after treatment with ethylene for as little as 12 hours. The findings indicate that some of the ethylene responses may be due to a stabilizing effect on microtubules in plant …
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Coherent control of polarized neutron interferometry
… of film rotators are presented showing a spin nutation > 90° from incident orientation. An architecture is presented for which any nutation angle can be achieved by tuning the separation of two composite film structures. We also propose an experimental implementation of the deterministic …
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Nuclear Magnetic Resonance Studies of the Effect of Vortices on the High Temperature Superconductor Yttrium Barium Copper Oxide
… vortices and the physics of these materials. NMR nutation curves show that the vortices produce lossy (Ohmic) conduction in this material and greatly enhance the penetration depth over the London value. This enhancement is necessary to study crystal samples. The vortices induce supercurrents in …
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Nuclear magnetic resonance studies of the effect of vortices on the high temperature superconductor YBa2̳Cu3̳O7̳
… vortices and the physics of these materials. NMR nutation curves show that the vortices produce lossy (Ohmic) conduction in this material and greatly enhance the penetration depth over the London value. This enhancement is necessary to study crystal samples. The vortices induce supercurrents in …
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Design, analysis, and testing of a precision guidance, navigation, and control system for a dual-spinning Cubesat
… of the payload's angular momentum induces nutation behavior. An extended Kalman filter is implemented on a 16-bit P1C24 microcontroller to combine gyroscope, limb sensor, and magnetometer data to provide attitude estimation accuracy of approximately 20 arcminutes. Simulations show that the …
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Measurement and Modeling of OPNMR Phenomena in GaAs Semiconductors
… are observations of perturbations to the nutation and echo behavior of GaAs under optical pumping conditions.</p>
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Collective behavior of driven Janus colloids in external fields
… field, a single Janus sphere performs curious nutation-like motion with adjustable phases. By synchronizing their dynamics, these magnetic Janus spheres self-assembles into microtubular structures that further synchronize with the constituent particles. Upon the introduction of AC electric …
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Hybrid Induction Drive for a Magnetically Levitated Control Moment Gyroscope
… up to 3.0 μNm were measured, with no significant nutation observed, indicating such a hybrid drive may be a viable architecture for future reaction sphere ACS designs requiring both rotor simplicity and 6 axes of control.
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Accurate monitoring of x, y, and z magnetization for analysis of hardware and pulse sequence performance in NMR spectroscopy
… were examined showing that an expected pulse nutation angle, such as a 90° pulse, is only achieved for a very small portion of the sample. The protocol was also used to assess the performance of the widely used inversion-recovery sequence (180° - τ - 90°) for spin-lattice relaxation …
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Experimental Investigation into the Long-Term Seismic Performance of Dry Storage Casks
… These motions turn into a precession and nutation motion, with or without sliding, when rocking about two or more directions simultaneously. Anchored casks resisted sliding and uplift, and the use of stretch length anchors provided more ductility and resilience when compared to …
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The Use of Driven Equilibrium Conditions in the Measurement of NMR Relaxation Times
… technique depends on rapid multipulsing at nutation angles, normally less than 90^o. Work in this area has highlighted the possible time saving for spectral acquisition over the classical technique (90^o-5T_1)_n. A new method based on these principles has been developed which permits the …
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Optically induced orientational transitions in nematic liquid crystals
… and corresponds to a precession and nutation of the director. As the intensity increases further, this state disappears at a certain critical value where the period of nutation becomes infinite. There a strongly hysteretic transition to a state with large reorientation occurs via a …
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Development of an end-effector system for autonomous spraying applications and radiation surveying
This thesis presents the design and testing of a scale proof-of-concept prototype end-effector system for autonomous shotcrete application and radiation surveying in underground uranium mining environments. The prototype end-effector system presented consists of two functionally distinct prototype …
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High-precision pointing and attitude estimation and control algorithms for hardware-constrained spacecraft
… to the decreasing momentum, which excites nutation in the spacecraft and maintains a full-rank nonlinear observability matrix. To search for the Sun, a guidance and control law is developed that efficiently searches the sky while navigating based on the body magnetic field direction alone …
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Optical Performance and Prototyping of a Liquid Lens Laser Communications Transceiver
… the receive path, and strategies to beacon using nutation. Characterization of prototype 1550 nm (optical C-band) optimized lenses from Corning Varioptic are also characterized. Preliminary simulation results for steering multiple beam using a single optical train of variable focuses lenses is …