On the Axisymmetric Thermoelastic Problem in Bispherical Coordinates

1967 ◽  
Vol 34 (4) ◽  
pp. 975-978
Author(s):  
W. E. Warren ◽  
J. A. Weese
Keyword(s):  
Elastic Medium ◽  
Interference Effect ◽  
Separation Distance ◽  
Thermoelastic Problem ◽  
The Other ◽  
Zero Temperature ◽  
Uniform Temperature ◽  
Thermoelastic Analysis ◽  
Spherical Cavities ◽  
Bispherical Coordinates

Results of the thermoelastic analysis of an infinite elastic medium containing two arbitrary-sized spherical cavities with arbitrary separation distance are presented graphically. Of particular interest is the interference effect of one cavity on the other. The cavity surfaces are assumed to be held at uniform temperature while zero temperature prevails at infinity. Examples treated include those for which the cavity surfaces are stress-free and those for which individually self-equilibrated rigid liners are bonded to the cavity surfaces.

The Axisymmetric Thermoelastic Problem in Bispherical Coordinates

1967 ◽  
Vol 34 (1) ◽  
pp. 146-152
Author(s):  
W. E. Warren ◽  
J. A. Weese
Keyword(s):  
Half Space ◽  
Spherical Cavity ◽  
Thermal Conditions ◽  
Separation Distance ◽  
The Body ◽  
Graphical Form ◽  
Zero Temperature ◽  
Spherical Cavities ◽  
Thermoelastic Problems ◽  
Bispherical Coordinates

Analytical methods are developed for treating steady-state axisymmetric thermoelastic problems defined in bispherical coordinates. Possible geometrical configurations include the infinite space with two spherical cavities of arbitrary radii and separation distance, the half-space with a spherical cavity, and the thick-walled shell having eccentric spherical boundaries. Thermal conditions must be prescribed at the surface of the body such that the temperature distribution is uniquely determined. The surfaces of the body are traction free. Numerical results for a half-space containing a spherical cavity heated to constant temperature with zero temperature on the plane and at infinity are presented in graphical form for representative geometrical variations.

Effects of Light on Schooling and Feeding of Jack Mackerel, Trachurus symmetricus

1968 ◽  
Vol 25 (2) ◽  
pp. 393-407 ◽  
Author(s):  
John R. Hunter
Keyword(s):  
Motion Picture ◽  
Nearest Neighbor ◽  
Motion Pictures ◽  
Separation Distance ◽  
The Other ◽  
Angular Deviation ◽  
Jack Mackerel ◽  
A Value

Schools of six jack mackerel each were photographed with infrared film at eight levels of luminance and also in darkness. Three indices were used to measure the behavior of the school from motion pictures. Two of the indices, mean distance to nearest neighbor and mean separation distance, were measures of the distances between individuals in a school; the other, mean angular deviation, was a measure of differences in orientation between individuals. A value for each index was calculated for each motion picture frame.From 12.1 to 6 × 10−6 ft-L no differences existed in the angular deviation of the school or in the distances between fish. At 6 × 10−7 ft-L the intervals between fish were much larger than at higher levels of brightness and groups showed little uniformity in their orientation. Below 6 × 10−7 ft-L (darkness) schools were dispersed and the distributions of values of angular deviation were random.The ability of jack mackerel to feed on live adult Artemia was also tested at eight levels of luminance and in darkness. The number of Artemia eaten at 6 × 10−5 ft-L was about half of that eaten at the normal daytime level of 12.1 ft-L. Few Artemia were eaten at 6 × 10−7 ft-L and none in darkness.Comparison of these data with measurements of light in the sea indicated that jack mackerel probably would be able to maintain schools near the surface on a moonless starlit night and that they probably could feed effectively near the surface on a full moonlight night.

scholarly journals The Effect of Several Intertrial Intervals on the 1 Hz Interference Effect

1981 ◽  
Vol 8 (1) ◽  
pp. 61-65 ◽  
Author(s):  
John Gaito ◽  
Stephen T. Gaito
Keyword(s):  
Brain Stimulation ◽  
Interference Effect ◽  
Intertrial Interval ◽  
Sine Wave ◽  
The Other ◽  
Steady Increase ◽  
Threshold Intensity ◽  
Effective Threshold ◽  
Effective Threshold Intensity ◽  
Group A

SUMMARYExperiments were conducted to evaluate the effect of two intertrial intervals of 1-Hz brain stimulation on kindling behavior induced by 60-Hz sine wave stimulation. In two experiments, the effective threshold intensity (ETI) to elicit a convulsion was determined on four separate occasions with 5 days of daily trials between determinations. On each day experimental rats were stimulated with 1-Hz current on the first and third trials for 120 seconds duration and with 60-Hz current for 30 seconds on the second trial (1-60-1 group). A second group was stimulated with 60-Hz current on each trial (60-60-60 group). A third group received no stimulation on Trials 1 and 3 and 60-Hz current on Trial 2 (X-60-X group). In Experiment I, the intertrial interval was 3 hours; a 24 hour interval was used in Experiment 2. The results were similar in both experiments. For the 1-60-1 group, there was a steady increase in the intensity required to elicit a convulsion with 60-Hz current from ETI to ETI. However, the 24 hour interval produced a lesser effect than did the 3 hour interval (or the 1 hour interval used in previous experiments). Rats in the other groups maintained relatively stable values from ETI to ETI, with a slight decline occurring. Suppression of convulsive behaviour on daily trials was present with the 1-60-1 groups, and nonexistent with the other groups.

scholarly journals PERSISTENCE IN THE ZERO-TEMPERATURE DYNAMICS OF THE Q-STATES POTTS MODEL ON UNDIRECTED-DIRECTED BARABÁSI–ALBERT NETWORKS AND ERDÖS–RÉNYI RANDOM GRAPHS

2008 ◽  
Vol 19 (12) ◽  
pp. 1777-1785 ◽  
Author(s):  
F. P. FERNANDES ◽  
F. W. S. LIMA
Keyword(s):  
Random Graphs ◽  
Potts Model ◽  
Finite Size ◽  
Glauber Dynamics ◽  
The Other ◽  
Finite Size Effect ◽  
Zero Temperature ◽  
Temperature Dynamics ◽  
Short Times ◽  
Q Values

The zero-temperature Glauber dynamics is used to investigate the persistence probability P(t) in the Potts model with Q = 3, 4, 5, 7, 9, 12, 24, 64, 128, 256, 512, 1024, 4096, 16 384, …, 230 states on directed and undirected Barabási–Albert networks and Erdös–Rényi (ER) random graphs. In this model, it is found that P(t) decays exponentially to zero in short times for directed and undirected ER random graphs. For directed and undirected BA networks, in contrast it decays exponentially to a constant value for long times, i.e., P(∞) is different from zero for all Q values (here studied) from Q = 3, 4, 5, …, 230; this shows "blocking" for all these Q values. Except that for Q = 230 in the undirected case P(t) tends exponentially to zero; this could be just a finite-size effect since in the other "blocking" cases you may have only a few unchanged spins.

scholarly journals ADIABATIC EFFECTIVE ACTION FOR VORTICES IN NEUTRAL AND CHARGED SUPERFLUIDS

1996 ◽  
Vol 10 (15) ◽  
pp. 1875-1894 ◽  
Author(s):  
M. HATSUDA ◽  
M. SATO ◽  
S. YAHIKOZAWA ◽  
T. HATSUDA
Keyword(s):  
Effective Mass ◽  
Vortex Dynamics ◽  
Effective Action ◽  
Vortex Core ◽  
Berry Phase ◽  
Inertial Mass ◽  
The Other ◽  
Zero Temperature ◽  
Magnus Force ◽  
Phase Term

Adiabatic effective action for vortices in neutral and charged superfluids at zero temperature are calculated using the topological Landau-Ginzburg theory recently proposed by Hatsuda, Yahikozawa, Ao and Thouless, and vortex dynamics are examined. The Berry phase term arising in the effective action naturally yields the Magnus force in both neutral and charged superfluids. It is shown that in neutral superfluid there is only one degree of freedom, namely the center of vorticities, and the vortex energy is proportional to the sum of all vorticities so that it is finite only for the vanishing total vorticity of the system. On the other hand the effective mass and the vortex energy for a vortex in charged superfluids are defined individually as expected. The effects of the vortex core on these quantities are also estimated. The possible depinning scenario which is governed by the Magnus force and the inertial mass is also discussed.

Transient Heat Conduction in an Infinite Plate With a Transverse Circular Cylindrical Hole

1973 ◽  
Vol 95 (3) ◽  
pp. 414-416 ◽  
Author(s):  
C. D. Michalopoulos ◽  
J. J. Seco
Keyword(s):  
Heat Conduction ◽  
Temperature Distribution ◽  
Infinite Plate ◽  
Transient Heat Conduction ◽  
Cylindrical Hole ◽  
The Other ◽  
Graphical Form ◽  
Zero Temperature ◽  
Temperature Distributions ◽  
Axisymmetric Temperature

The flow of heat in an infinite plate with a transverse circular cylindrical hole is considered. The boundary conditions are zero temperature on the cylindrical surface and arbitrary but axisymmetric temperature distributions on the plane surfaces. The solution is obtained by means of Laplace and an unconventional Hankel transforms. Numerical results are given in graphical form for a plate with a step temperature distribution on one face and zero temperature on the other.

Tachyonic braneworld mimetic cosmology

2019 ◽  
Vol 34 (21) ◽  
pp. 1950162 ◽  
Author(s):  
S. Davood Sadatian ◽  
Alireza Sepehri
Keyword(s):  
Cosmological Model ◽  
Separation Distance ◽  
The Other ◽  
Late Time ◽  
Moduli Stabilization ◽  
Inflation Model ◽  
Braneworld Model ◽  
And Behavior ◽  
The Universe ◽  
Mimetic Gravity

Recently, some authors have generalized the idea of mimetic gravity to a Randall–Sundrum II braneworld model [L. Randall and R. Sundrum, Phys. Rev. Lett. 83, 3370 (1999); L. Randall and R. Sundrum, Phys. Rev. Lett. 83, 4690 (1999)] and introduced Braneworld Mimetic Cosmology. In this paper, we extend their new cosmological model to brane–anti-brane systems and obtain the explicit form of potential which appeared in their action. This potential depends on the tachyonic fields, the separation distance between two branes and time. On the other hand, our universe is located on one of the branes and its evolution is controlled by the potential between two branes. By passing time and decreasing the separation distance between branes, more energy dissolves into branes and the universe expands. In the following, we presented the physical applications such as late time accelerating phase, inflation model and behavior of perturbations, with respect to brane–anti-brane system. Finally, we briefly discussed the moduli stabilization of the model.

Thermostatics of an elastic Cosserat plate containing a circular hole

1971 ◽  
Vol 70 (1) ◽  
pp. 169-174 ◽  
Author(s):  
İ. T. Gürgöze
Keyword(s):  
Temperature Gradient ◽  
General Theory ◽  
Circular Hole ◽  
Thermal Stresses ◽  
Plate Theory ◽  
The Other ◽  
Uniform Temperature ◽  
Classical Plate Theory ◽  
Cosserat Surface ◽  
Limiting Case

AbstractIn this paper, the general theory of a Cosserat surface given by Green, Naghdi and Wainwright(1), has been applied to the problem of a thermo-elastic Cosserat plate containing a circular hole of radius a. We assume that the major surfaces of the plate and the boundary of the hole are thermally insulated and that a uniform temperature gradient τ exists at infinity. In the limiting case, when h/a → 0, where h is the thickness of the plate, the thermal stresses at the circular hole reduce to those obtained by Florence and Goodier (4), by means of the classical plate theory. Results for the other limiting case h/a → ∞ are also given.

Effect of the Inclination on Three-Dimensional Incompressible Fluid Flow in a Discretely Heated Cavity

2013 ◽  
Vol 597 ◽  
pp. 3-8
Author(s):  
Lahoucine Belarche ◽  
Btissam Abourida ◽  
Slawomir Smolen ◽  
Touria Mediouni
Keyword(s):  
Heat Transfer ◽  
Heat Flux ◽  
Fluid Flow ◽  
Vertical Wall ◽  
Three Dimensional ◽  
The Other ◽  
Uniform Temperature ◽  
Incompressible Fluid Flow ◽  
Electronic Components ◽  
Flow And Heat Transfer

Natural convection in inclined cubic cavity, discretely heated, is studied numerically using a three-dimensional finite volume formulation. Two heating square portions are placed on the vertical wall of the enclosure, while the rest of the considered wall is adiabatic. These sections, similar to the integrated electronic components, generate a heat flux q". The opposite vertical wall is maintained at a cold uniform temperature Tc and the other walls are adiabatic. The fluid flow and heat transfer in the cavity are studied for different sets of the governing parameters, namely the Rayleigh number Ra (103 ≤ Ra ≤ 107), the cavity inclination γ (- 45° ≤ γ ≤ 45°) and the position of the heating sections λ (0.3 ≤ λ ≤ 0.7). The dimensions of the heater sections, ε = D / H and the longitudinal aspect ratio of the cavity Ax = H / L are respectively fixed to 0.35 and 1.

Heat Transfer and Temperature Field Experiments in a Cavity With Rotation, Recirculation, and Coolant Throughflow

1975 ◽  
Vol 97 (1) ◽  
pp. 22-28 ◽  
Author(s):  
E. M. Sparrow ◽  
T. C. Buszkiewicz ◽  
E. R. G. Eckert
Keyword(s):  
Heat Transfer ◽  
Field Experiments ◽  
Rotating Disk ◽  
Separation Distance ◽  
The Other ◽  
Fluid Temperature ◽  
Transfer Coefficients ◽  
Heat Transfer Coefficients ◽  
Annular Gap ◽  
Isothermal Fluid

Local wall heat transfer coefficients and fluid temperature distributions were measured in a cavity consisting of a pair of parallel disks and a cylindrical shroud. One of the disks was rotating, whereas the other disk and the shroud were stationary. Coolant air entered the cavity through a central aperture in the rotating disk and exited through an annular gap at the rim of the rotating disk. The coolant flow rate, the disk rotational speed, and the cavity aspect ratio (disk separation distance to radius) were varied throughout the course of the experiments. The latter parameter took on values as large as two. The heat transfer results and the fluid isotherm maps suggested that the flow pattern within the cavity was markedly different depending upon whether the coolant stream or the pumping action of the rotating disk was predominant. The surface distributions of the heat transfer coefficients reversed the direction of their spatial variation over the range from no rotation to high rotation. However, the maximum values of the Nusselt number curves for no rotation were as high as the maximum values of the curves for corresponding cases with high rotation. The isotherm maps for the no-rotation cases revealed that the major portion of the cavity was filled with nearly isothermal fluid. On the other hand, in the presence of strong rotation, there were substantial fluid temperature variations throughout the cavity.

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