The Distribution of Inductive Charge on the Plane of a Conductor under a Charged Thin Ring

Relatively few data on the development of the amygdaloid complex are available only at the light microscopic level (1-3). The existence of just general morphological criteria requires the performance of other investigations in particular ultrastructural in order to obtain new and more detailed information about the changes in the amygdaloid complex during development.The prenatal and postnatal development of rat amygdaloid complex beginning from the 12th embrionic day (ED) till the 33rd postnatal day (PD) has been studied. During the early stages of neurogenesis (12ED), the nerve cells were observed to be closely packed, small-sized, with oval shape. A thin ring of cytoplasm surrounded their large nuclei, their nucleoli being very active with various size and form (Fig.1). Some cells possessed more abundant cytoplasm. The perikarya were extremely rich in free ribosomes. Single sacs of the rough endoplasmic reticulum and mitochondria were observed among them. The mitochondria were with light matrix and possessed few cristae. Neural processes were viewed to sprout from some nerve cells (Fig.2). Later the nuclei were still comparatively large and with various shape.

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Tire Vibrations

Tire Science and Technology ◽

10.2346/1.2167240 ◽

1977 ◽

Vol 5 (4) ◽

pp. 202-225 ◽

Cited By ~ 35

Author(s):

G. R. Potts ◽

C. A. Bell ◽

L. T. Charek ◽

T. K. Roy

Keyword(s):

Natural Frequencies ◽

Standing Waves ◽

Resonant Mode ◽

Mode Shapes ◽

Resonant Vibrations ◽

Resonant Frequencies ◽

Radial Tire ◽

Analysis Techniques ◽

Thin Ring ◽

Good Agreement

Abstract Natural frequencies and vibrating motions are determined in terms of the material and geometric properties of a radial tire modeled as a thin ring on an elastic foundation. Experimental checks of resonant frequencies show good agreement. Forced vibration solutions obtained are shown to consist of a superposition of resonant vibrations, each rotating around the tire at a rate depending on the mode number and the tire rotational speed. Theoretical rolling speeds that are upper bounds at which standing waves occur are determined and checked experimentally. Digital Fourier transform, transfer function, and modal analysis techniques used to determine the resonant mode shapes of a radial tire reveal that antiresonances are the primary transmitters of vibration to the tire axle.

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Bending of Thin Ring-Sector Plates

Journal of Applied Mechanics ◽

10.1115/1.4010350 ◽

1951 ◽

Vol 18 (4) ◽

pp. 359-363

Author(s):

L. I. Deverall ◽

C. J. Thorne

Keyword(s):

Continuous Function ◽

Bending Moment ◽

Circular Ring ◽

Circular Plates ◽

Thin Ring ◽

Special Cases ◽

Edge Conditions

Abstract General expressions for the deflection of plates whose planform is a sector of a circular ring are given for cases in which the straight edges have arbitrary but given deflection and bending moment. The solutions are given for all combinations of physically important edge conditions on the two circular edges. Sectors of circular plates are included as special cases. Solutions are given for a general load which is a continuous function of r, and a sectionally continuous function of θ, where r and θ are the usual polar co-ordinates with the pole at the center of the ring. Several specific examples are given.

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Crushing of an Elastic-Perfectly Plastic Ring or Tube Between Two Planes

Journal of Applied Mechanics ◽

10.1115/1.3172951 ◽

1987 ◽

Vol 54 (1) ◽

pp. 159-164 ◽

Cited By ~ 17

Author(s):

C. Y. Wang

Keyword(s):

Plastic Deformation ◽

Numerical Integration ◽

Mathematical Problem ◽

Plastic Ring ◽

Perfectly Plastic ◽

Analytical Approximations ◽

Original Shape ◽

Thin Ring ◽

Elastic Perfectly Plastic

A thin ring is crushed between two rigid planes. Due to plastic deformation the ring does not recover its original shape when the compression is removed. For an elastic-perfectly plastic flexural material, the ring undergoes two to five different stages. The mathematical problem is formulated and solved by exact numerical integration and accurate analytical approximations.

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Dynamics of MEMS-Based Angular Rate Sensors Excited via External Electrostatic Forces

Volume 7A: Dynamics, Vibration, and Control ◽

10.1115/imece2020-24178 ◽

2020 ◽

Author(s):

Ibrahim F. Gebrel ◽

Ligang Wang ◽

Samuel F. Asokanthan

Keyword(s):

Dynamic Behavior ◽

Electrostatic Force ◽

Angular Rate ◽

Equations Of Motion ◽

Ring Structure ◽

Dynamic Responses ◽

Actuator Dynamics ◽

Vibratory Gyroscopes ◽

Thin Ring ◽

The Mathematical Model

Abstract This paper investigates the dynamic behavior of rotating MEMS-based vibratory gyroscopes which employs a thin ring as the vibrating flexible element. The mathematical model for the MEMS ring structure as well as a model for the nonlinear electrostatic excitation forces are formulated. Galerkin’s procedure is employed to reduce the equations of motion to a set of ordinary differential equations. Understanding the effects of nonlinear actuator dynamics is considered important for characterizing the dynamic behavior of such devices. A suitable theoretical model to generate nonlinear electrostatic force that acts on the MEMS ring structure is formulated. Dynamic responses in the driving and the sensing directions are examined via time responses, phase diagram, and Poincare’ map plots when the input angular motion and the nonlinear electrostatic force are considered simultaneously. The analysis is envisaged to aid fabrication of this class of devices as well as for providing design improvements in MEMS Ring-based Gyroscopes.

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3.25. Radiative avalanche driven by a circumnuclear starburst torus

Symposium - International Astronomical Union ◽

10.1017/s0074180900084382 ◽

1998 ◽

Vol 184 ◽

pp. 139-140

Author(s):

Ken Ohsuga ◽

Masayuki Umemura

Keyword(s):

Angular Momentum ◽

Active Galactic Nuclei ◽

Drag Force ◽

Compact Star ◽

Star Clusters ◽

Galactic Nuclei ◽

Curvature Radius ◽

Thin Ring ◽

Velocity Dispersions ◽

Half Thickness

Recently, a novel mechanism for fueling active galactic nuclei (AGNs) has been proposed by Umemura et al. (1997a, b). That is a radiative avalanche, in which a rotating gas disk sheds angular momentum due to the radiation drag force exerted by starlight from circumnuclear starbursts, so that the mass accretion onto nuclei is driven. Originally, a thin ring of a starburst region has been assumed for simplicity. However, recent observations have revealed that circumnuclear starburst rings have radial extension of ∼ 10pc up to kpc, and they often consist of compact star clusters of < 10pc Thus, the ratio of the half thickness to curvature radius of the ring can be minimally less than one tenth when all the star clusters are aligned on a plane of an inner gas disk, while the ratio could be larger if the distributions of star clusters are extended due to some velocity dispersions.

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X-ray light curves from realistic polar cap models: inclined pulsar magnetospheres and multipole fields

Monthly Notices of the Royal Astronomical Society ◽

10.1093/mnras/stz2524 ◽

2019 ◽

Vol 490 (2) ◽

pp. 1774-1783 ◽

Cited By ~ 9

Author(s):

Will Lockhart ◽

Samuel E Gralla ◽

Feryal Özel ◽

Dimitrios Psaltis

Keyword(s):

Light Curve ◽

Quadrupole Moment ◽

Large Scale ◽

Realistic Model ◽

Light Curves ◽

X Ray ◽

Polar Caps ◽

Thin Ring ◽

Magnetic Quadrupole ◽

South Asymmetry

ABSTRACT Thermal X-ray emission from rotation-powered pulsars is believed to originate from localized ‘hotspots’ on the stellar surface occurring where large-scale currents from the magnetosphere return to heat the atmosphere. Light-curve modelling has primarily been limited to simple models, such as circular antipodal emitting regions with constant temperature. We calculate more realistic temperature distributions within the polar caps, taking advantage of recent advances in magnetospheric theory, and we consider their effect on the predicted light curves. The emitting regions are non-circular even for a pure dipole magnetic field, and the inclusion of an aligned magnetic quadrupole moment introduces a north–south asymmetry. As the quadrupole moment is increased, one hotspot grows in size before becoming a thin ring surrounding the star. For the pure dipole case, moving to the more realistic model changes the light curves by $5\!-\!10{{\, \rm per\, cent}}$ for millisecond pulsars, helping to quantify the systematic uncertainty present in current dipolar models. Including the quadrupole gives considerable freedom in generating more complex light curves. We explore whether these simple dipole+quadrupole models can account for the qualitative features of the light curve of PSR J0437−4715.

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Development of Compact Damper Bearing

Volume 1: 20th Biennial Conference on Mechanical Vibration and Noise, Parts A, B, and C ◽

10.1115/detc2005-84775 ◽

2005 ◽

Author(s):

Hiroshi Kanki ◽

Yosichika Sato ◽

Takayuki Ueshima

Keyword(s):

Rotating Machinery ◽

Rolling Element Bearing ◽

Squeeze Film ◽

Test Results ◽

Thin Ring ◽

Compact Size ◽

Standard Design ◽

Rolling Element ◽

Aero Engine ◽

Element Bearing

The squeeze film damper bearings have been successfully applied for important rotating machinery such as aero engine, high pressure centrifugal compressors[1] and steam turbine[2]. This paper proposes the expansion of application of the damper bearing for small and medium sized rotating machinery. The new damper has a compact size that enable standard design combined with rolling element bearing. A new design of the damper is presented. The new design consists of thin ring and special patterned wire cut grooves. The design analysis and experimental study are presented. The dynamic tests were carried out for this model damper, one is no side seal and the other is with side seals in both ends. Test results showed the sufficient damping effect for actual applications.

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