The Experts below are selected from a list of 53499 Experts worldwide ranked by ideXlab platform
Bernhard J. M. Hess - One of the best experts on this subject based on the ideXlab platform.
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Inertial representation of Angular Motion in the vestibular system of rhesus monkeys. II. Otolith-controlled transformation that depends on an intact cerebellar nodulus.
Journal of neurophysiology, 1995Co-Authors: Dora E. Angelaki, Bernhard J. M. HessAbstract:1. We recently studied the spatial representation of Angular Motion signals in rhesus monkeys by examining the orientation of postrotatory vestibuloocular responses during tilt of the head and body...
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Inertial representation of Angular Motion in the vestibular system of rhesus monkeys. I. Vestibuloocular reflex.
Journal of neurophysiology, 1994Co-Authors: Dora E. Angelaki, Bernhard J. M. HessAbstract:1. The spatial organization of the vestibuloocular reflex (VOR) was studied in six rhesus monkeys by applying fast, short-lasting, passive head and body tilts immediately after constant-velocity rotation (+/- 90 degrees/s) about an earth-vertical axis. Two alternative hypotheses were investigated regarding the reference frame used for coding Angular Motion. 1) If the vestibular system is organized in head-centered coordinates, postrotatory eye velocity would decay invariably along the direction of applied head Angular acceleration. 2) Alternatively, if the vestibular system codes Angular Motion in inertial, gravity-centered coordinates, postrotatory eye velocity would decay along the direction of gravity. 2. Horizontal VOR was studied with the monkeys upright. Pitch (roll) tilts away from upright elicited a transient vertical (torsional) VOR and shortened the time constant of the horizontal postrotatory slow phase velocity. In addition, an orthogonal torsional (after pitch tilts) or vertical (after roll tilts) response gradually built up. As a result, the eye velocity vector transiently deviated in the roll (pitch) plane and then gradually rotated in the same direction as gravity in the pitch (roll) head plane until the orthogonal component reached a peak value. Subsequently, the residual postrotatory eye velocity decayed along a line parallel to gravity. 3. The time constant of the horizontal postrotatory response was maximal in upright position (21.5 +/- 5.7 s, mean +/- SD) and minimal after tilts to prone (3.8 +/- 0.7 s), supine (4.5 +/- 1.2 s), and ear-down (5.2 +/- 1.6 s) positions. A similar dependence on head orientation relative to gravity characterized the dynamics of the resultant eye velocity vector in the pitch and roll planes. 4. Torsional VOR was studied with the monkeys in supine or prone position. Pitch (yaw) tilts from the supine or prone position toward upright (ear-down) position elicited a transient vertical (horizontal) VOR and shortened the time constant of the torsional postrotatory response while a horizontal (vertical) orthogonal component slowly built up. As a result the eye velocity vector gradually rotated in the pitch (yaw) plane until the orthogonal component reached a peak value. Subsequently residual postrotatory eye velocity decayed along a line parallel to gravity. 5. The time constant of the torsional postrotatory response in supine/prone positions was 16.5 +/- 6.8 s. After tilts from supine/prone positions toward upright position, time constants decreased and were minimal after tilts to upright position (2.7 +/- 0.7 s).(ABSTRACT TRUNCATED AT 400 WORDS)
Seiji Kawamura - One of the best experts on this subject based on the ideXlab platform.
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Standard quantum limit of Angular Motion of a suspended mirror and homodyne detection of a ponderomotively squeezed vacuum field
Physical Review A, 2016Co-Authors: Yutaro Enomoto, Koji Nagano, Seiji KawamuraAbstract:Compared to the quantum noise in the measurement of the translational Motion of a suspended mirror using laser light, the quantum noise in the measurement of the Angular Motion of a suspended mirror has not been investigated intensively despite its potential importance. In this article, an expression for the quantum noise in the Angular Motion measurement is explicitly derived. The expression indicates that one quadrature of the vacuum field of the first-order Hermite-Gaussian mode of light causes quantum sensing noise and the other causes quantum back-action noise, or in other words the first-order vacuum field is ponderomotively squeezed. It is also shown that the Gouy phase shift the light acquires between the mirror and the position of detection of the light corresponds to the homodyne angle. Therefore, the quantum back-action noise can be canceled and the standard quantum limit can be surpassed by choosing the appropriate position of detection analogously to the cancellation of quantum radiation pressure noise by choosing an appropriate homodyne angle.
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standard quantum limit of Angular Motion of a suspended mirror and homodyne detection of ponderomotively squeezed vacuum of the first order hermite gaussian modes of light field
arXiv: Quantum Physics, 2016Co-Authors: Yutaro Enomoto, Koji Nagano, Seiji KawamuraAbstract:Compared to the quantum noise in the measurement of the translational Motion of a suspended mirror using laser light, the quantum noise in the measurement of the Angular Motion of a suspended mirror has not been investigated intensively despite its potential importance. In this letter, an expression for the quantum noise in the Angular Motion measurement is explicitly derived. The expression indicates that one quadrature of the vacuum field of the first-order Hermite-Gaussian mode of light causes quantum sensing noise and the other causes quantum backaction noise, or in other words the first-order vacuum field is ponderomotively squeezed. It is also shown that the Gouy phase shift the light acquires between the mirror and the position of detection of the light corresponds to the homodyne angle. Therefore, the quantum backaction noise can be cancelled and the standard quantum limit can be surpassed by choosing the appropriate position of detection analogously to the cancellation of quantum radiation pressure noise by choosing an appropriate homodyne angle.
Anton V. Doroshin - One of the best experts on this subject based on the ideXlab platform.
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Exact solutions for Angular Motion of coaxial bodies and attitude dynamics of gyrostat-satellites
International Journal of Non-Linear Mechanics, 2013Co-Authors: Anton V. DoroshinAbstract:Abstract Dynamics of the torque-free Angular Motion of gyrostat-satellites and dual-spin spacecraft are examined. New analytical solutions for the Angular moment components are obtained in terms of Jacobi elliptic functions. Also analytical solutions for Euler's angles are found. These solutions can be used for a dual-spin spacecraft and gyrostat-satellites attitude dynamics analysis and synthesis.
N. A. Yudanov - One of the best experts on this subject based on the ideXlab platform.
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Angular Motion of the TNS-0 # 2 Nanosatellite after Launch from the International Space Station
Cosmic Research, 2019Co-Authors: D. S. Ivanov, M. Yu. Ovchinnikov, O. A. Pantsyrnyi, A. S. Selivanov, A. S. Sergeev, I. O. Fedorov, O. E. Khromov, N. A. YudanovAbstract:Description of the passive magnetic attitude control system of the TNS-0 # 2 nanosatellite is presented. The parameters of the main components of the attitude control system are given and their choice is justified. Using telemetry data, the passive Angular Motion of TNS-0 # 2 was determined after processing measurements of the on-board sensors after launching from the ISS on August 17, 2017. The damping time of the initial Angular velocity was estimated. The accuracy of magnetic stabilization after the end of transient processes was determined.
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Angular Motion of the tns 0 2 nanosatellite after launch from the international space station
Cosmic Research, 2019Co-Authors: D. S. Ivanov, O. A. Pantsyrnyi, A. S. Selivanov, A. S. Sergeev, I. O. Fedorov, O. E. Khromov, Yu M Ovchinnikov, N. A. YudanovAbstract:Description of the passive magnetic attitude control system of the TNS-0 # 2 nanosatellite is presented. The parameters of the main components of the attitude control system are given and their choice is justified. Using telemetry data, the passive Angular Motion of TNS-0 # 2 was determined after processing measurements of the on-board sensors after launching from the ISS on August 17, 2017. The damping time of the initial Angular velocity was estimated. The accuracy of magnetic stabilization after the end of transient processes was determined.
Dora E. Angelaki - One of the best experts on this subject based on the ideXlab platform.
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Inertial representation of Angular Motion in the vestibular system of rhesus monkeys. II. Otolith-controlled transformation that depends on an intact cerebellar nodulus.
Journal of neurophysiology, 1995Co-Authors: Dora E. Angelaki, Bernhard J. M. HessAbstract:1. We recently studied the spatial representation of Angular Motion signals in rhesus monkeys by examining the orientation of postrotatory vestibuloocular responses during tilt of the head and body...
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Inertial representation of Angular Motion in the vestibular system of rhesus monkeys. I. Vestibuloocular reflex.
Journal of neurophysiology, 1994Co-Authors: Dora E. Angelaki, Bernhard J. M. HessAbstract:1. The spatial organization of the vestibuloocular reflex (VOR) was studied in six rhesus monkeys by applying fast, short-lasting, passive head and body tilts immediately after constant-velocity rotation (+/- 90 degrees/s) about an earth-vertical axis. Two alternative hypotheses were investigated regarding the reference frame used for coding Angular Motion. 1) If the vestibular system is organized in head-centered coordinates, postrotatory eye velocity would decay invariably along the direction of applied head Angular acceleration. 2) Alternatively, if the vestibular system codes Angular Motion in inertial, gravity-centered coordinates, postrotatory eye velocity would decay along the direction of gravity. 2. Horizontal VOR was studied with the monkeys upright. Pitch (roll) tilts away from upright elicited a transient vertical (torsional) VOR and shortened the time constant of the horizontal postrotatory slow phase velocity. In addition, an orthogonal torsional (after pitch tilts) or vertical (after roll tilts) response gradually built up. As a result, the eye velocity vector transiently deviated in the roll (pitch) plane and then gradually rotated in the same direction as gravity in the pitch (roll) head plane until the orthogonal component reached a peak value. Subsequently, the residual postrotatory eye velocity decayed along a line parallel to gravity. 3. The time constant of the horizontal postrotatory response was maximal in upright position (21.5 +/- 5.7 s, mean +/- SD) and minimal after tilts to prone (3.8 +/- 0.7 s), supine (4.5 +/- 1.2 s), and ear-down (5.2 +/- 1.6 s) positions. A similar dependence on head orientation relative to gravity characterized the dynamics of the resultant eye velocity vector in the pitch and roll planes. 4. Torsional VOR was studied with the monkeys in supine or prone position. Pitch (yaw) tilts from the supine or prone position toward upright (ear-down) position elicited a transient vertical (horizontal) VOR and shortened the time constant of the torsional postrotatory response while a horizontal (vertical) orthogonal component slowly built up. As a result the eye velocity vector gradually rotated in the pitch (yaw) plane until the orthogonal component reached a peak value. Subsequently residual postrotatory eye velocity decayed along a line parallel to gravity. 5. The time constant of the torsional postrotatory response in supine/prone positions was 16.5 +/- 6.8 s. After tilts from supine/prone positions toward upright position, time constants decreased and were minimal after tilts to upright position (2.7 +/- 0.7 s).(ABSTRACT TRUNCATED AT 400 WORDS)
