On the inviscid stability of bi-layer axisymmetric coatings

This paper is concerned with the stability of fibre coatings at large Reynolds numbers. Both single- and double-layer coatings are considered; no restriction is placed on the coating thicknesses. Calculations for the maximum growth rate, together with the corresponding length scale of the instability, are presented. Rescaling with respect to the maximum growth rate generates universal dispersion relations over the unstable wavenumber range. For double-layer composite coatings, modifications are required when the density ratio becomes large.

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Non-normal stability analysis of a shear current under surface gravity waves

Journal of Fluid Mechanics ◽

10.1017/s0022112008002231 ◽

2008 ◽

Vol 609 ◽

pp. 49-58

Author(s):

D. AMBROSI ◽

M. ONORATO

Keyword(s):

Growth Rate ◽

Modal Analysis ◽

Gravity Waves ◽

Maximum Growth ◽

Maximum Growth Rate ◽

Surface Gravity ◽

Horizontal Shear ◽

Surface Gravity Waves ◽

Shear Current ◽

The Stability

The stability of a horizontal shear current under surface gravity waves is investigated on the basis of the Rayleigh equation. As the differential operator is non-normal, a standard modal analysis is not effective in capturing the transient growth of a perturbation. The representation of the stream function by a suitable basis of bi-orthogonal eigenfunctions allows one to determine the maximum growth rate of a perturbation. It turns out that, in the considered range of parameters, such a growth rate can be two orders of magnitude larger than the maximum eigenvalue obtained by standard modal analysis.

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Instabilities of a Baroclinic, Double Diffusive Frontal Zone

Journal of Physical Oceanography ◽

10.1175/2007jpo3770.1 ◽

2008 ◽

Vol 38 (4) ◽

pp. 840-861 ◽

Cited By ~ 10

Author(s):

W. D. Smyth

Keyword(s):

Growth Rate ◽

Frontal Zone ◽

Baroclinic Instability ◽

Flux Ratio ◽

Maximum Growth ◽

Maximum Growth Rate ◽

Variable Diffusivity ◽

The Stability ◽

Parameter Values ◽

Double Diffusive

Abstract The linear theory of double diffusive interleaving is extended to take account of baroclinic effects. This study goes beyond previous studies by including the possibility of modes with nonzero tilt in the alongfront direction, which allows for advection by the baroclinic frontal flow. This requires that the stability equations be solved numerically. The main example is based on observations of interleaving on the lower flank of Meddy Sharon, but a range of parameter values is covered, leading to conclusions that are relevant in a variety of oceanic regimes. The frontal zone is treated as infinitely wide with uniform gradients of temperature, salinity, and alongfront velocity. The stationary, vertically symmetric interleaving mode is shown to have maximum growth rate when its alongfront wavenumber is zero, providing validation for previous studies in which this property was assumed. Besides this, there exist two additional modes of instability: the ageostrophic Eady mode of baroclinic instability and a mode not previously identified. The new mode is oblique (i.e., it tilts in the alongfront direction), vertically asymmetric, and propagating. It is strongly dependent on boundary conditions, and its relevance in the ocean interior is uncertain as a result. Effects of variable diffusivity and buoyancy flux ratio are also considered.

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Stability of the solar wind against the whistler mode

Journal of Plasma Physics ◽

10.1017/s0022377800021528 ◽

1978 ◽

Vol 20 (2) ◽

pp. 225-230 ◽

Cited By ~ 5

Author(s):

P. Revathy

Keyword(s):

Growth Rate ◽

Solar Wind ◽

Relative Velocity ◽

Maximum Growth ◽

Maximum Growth Rate ◽

The Sun ◽

Thermal Velocity ◽

Whistler Mode ◽

Minimum Value ◽

The Stability

The stability of the solar wind against the whistler mode is analyzed. It is shown that the solar wind can become unstable owing to this mode after a distance of 100 R from the sun. The minimum value of the relative velocity (Ur) between ∝-particles and protons for the excitation of this instability is the proton thermal velocity αi. The maximum growth rate at 200 R occurs for the values of the parameters kρi = 0·3,(T┤/T∥)i = 0·3 and Ur/αi = 0·5.

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Water-bag stability theory for planar bounded plasmas with counter-streaming injection. Part 1. The neutralized diode

Journal of Plasma Physics ◽

10.1017/s0022377800025599 ◽

1975 ◽

Vol 14 (1) ◽

pp. 143-152 ◽

Cited By ~ 2

Author(s):

K. M. Hu ◽

E. H. Klevans

Keyword(s):

Growth Rate ◽

Lower Order ◽

Stability Theory ◽

Electron Distribution ◽

Electron Beams ◽

Maximum Growth ◽

Maximum Growth Rate ◽

Higher Order Modes ◽

The Stability ◽

System Approaches

The stability of a bounded, homogeneous, neutralized plasma with counter- streaming electron beams is analysed. A water-bag model is used to describe the electron distribution in velocity space, so that finite beam temperature and a background plasma are included in the theory. For boundary conditions, the absorber– source wall (the diode boundary) and the reflecting wall are considered. For the former, growth-rate calculations indicate that the instability is a combination of charge bunching (counter-streaming) and diode circuit effect. As the diode length increases, the growth rate of all modes in the system approaches the maximum growth rate. For the reflecting wall, as the length increases, the maximum growth rate transfers to higher and higher order modes with shorter wavelength, while the growth rate of the lower-order modes goes to zero.

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A note on growth curves of rabbit lines selected on growth rate or litter size

Animal Science ◽

10.1017/s000335610000698x ◽

1993 ◽

Vol 57 (2) ◽

pp. 332-334 ◽

Cited By ~ 13

Author(s):

A. Blasco ◽

E. Gómez

Keyword(s):

Growth Rate ◽

Litter Size ◽

Growth Curves ◽

Live Weight ◽

Maximum Growth ◽

Maximum Growth Rate ◽

Standard Errors ◽

Adult Weight ◽

Weight Growth ◽

Using Data

Two synthetic lines of rabbits were used in the experiment. Line V, selected on litter size, and line R, selected on growth rate. Ninety-six animals were randomly collected from 48 litters, taking a male and a female each time. Richards and Gompertz growth curves were fitted. Sexual dimorphism appeared in the line V but not in the R. Values for b and k were similar in all curves. Maximum growth rate took place in weeks 7 to 8. A break due to weaning could be observed in weeks 4 to 5. Although there is a remarkable similarity of the values of all the parameters using data from the first 20 weeks only, the higher standard errors on adult weight would make 30 weeks the preferable time to take data for live-weight growth curves.

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Reassessment of Maximum Growth Rates for C3 and C4 Crops

Experimental Agriculture ◽

10.1017/s0014479700008255 ◽

1978 ◽

Vol 14 (1) ◽

pp. 1-5 ◽

Cited By ~ 129

Author(s):

J. L. Monteith

Keyword(s):

Growth Rate ◽

Growth Rates ◽

Growing Season ◽

Maximum Growth ◽

Maximum Growth Rate ◽

Crop Growth ◽

Close Inspection ◽

Similar Difference ◽

Photosynthetic Efficiencies

SUMMARYFigures for maximum crop growth rates, reviewed by Gifford (1974), suggest that the productivity of C3 and C4 species is almost indistinguishable. However, close inspection of these figures at source and correspondence with several authors revealed a number of errors. When all unreliable figures were discarded, the maximum growth rate for C3 stands fell in the range 34–39 g m−2 d−1 compared with 50–54 g m−2 d−1 for C4 stands. Maximum growth rates averaged over the whole growing season showed a similar difference: 13 g m−2 d−1 for C3 and 22 g m−2 d−1 for C4. These figures correspond to photosynthetic efficiencies of approximately 1·4 and 2·0%.

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Interpretation of Experimental Data with Regard to the Activated Sludge Model No.1 and Calibration of the Model for Municipal Wastewater Treatment Plants

Water Science & Technology ◽

10.2166/wst.1992.0121 ◽

1992 ◽

Vol 25 (6) ◽

pp. 167-183 ◽

Cited By ~ 16

Author(s):

H. Siegrist ◽

M. Tschui

Keyword(s):

Experimental Data ◽

Growth Rate ◽

Activated Sludge ◽

Municipal Wastewater ◽

Wastewater Treatment Plants ◽

Treatment Plant ◽

Maximum Growth ◽

Maximum Growth Rate ◽

Municipal Wastewater Treatment ◽

Activated Sludge Model

The wastewater of the municipal treatment plants Zürich-Werdhölzli (350000 population equivalents), Zürich-Glatt (110000), and Wattwil (20000) have been characterized with regard to the activated sludge model Nr.1 of the IAWPRC task group. Zürich-Glatt and Wattwil are partly nitrifying treatment plants and Zürich-Werdhölzli is fully nitrifying. The mixing characteristics of the aeration tanks at Werdhölzli and Glatt were determined with sodium bromide as a tracer. The experimental data were used to calibrate hydrolysis, heterotrophic growth and nitrification. Problems arising by calibrating hydrolysis of the paniculate material and by measuring oxygen consumption of heterotrophic and nitrifying microorganisms are discussed. For hydrolysis the experimental data indicate first-order kinetics. For nitrification a maximum growth rate of 0.40±0.07 d−1, corresponding to an observed growth rate of 0.26±0.04 d−1 was calculated at 10°C. The half velocity constant found for 12 and 20°C was 2 mg NH4-N/l. The calibrated model was verified with experimental dam of me Zürich-Werdhölzli treatment plant during ammonia shock load.

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Factors which influence the timing of maximum growth rate of the head in low birthweight infants.

Archives of Disease in Childhood ◽

10.1136/adc.52.2.113 ◽

1977 ◽

Vol 52 (2) ◽

pp. 113-117 ◽

Cited By ~ 8

Author(s):

M Fujimura

Keyword(s):

Growth Rate ◽

Low Birthweight ◽

Maximum Growth ◽

Maximum Growth Rate

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Dietary Protein Requirements of Fishes — A Reassessment

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f87-244 ◽

1987 ◽

Vol 44 (11) ◽

pp. 1995-2001 ◽

Cited By ~ 52

Author(s):

Stephen H. Bowen

Keyword(s):

Growth Rate ◽

Dietary Protein ◽

Protein Concentration ◽

Trophic Ecology ◽

Maximum Growth ◽

Maximum Growth Rate ◽

Intake Rate ◽

Protein Requirement ◽

Fish Physiology ◽

Protein Retention

It is widely believed that fishes require more dietary protein than other vertebrates. Many aspects of fish physiology, nutrition, and trophic ecology have been interpreted within the context of this high protein requirement. Here, fishes are compared with terrestrial homeotherms in terms of (1) protein requirement for maintenance, (2) relative protein concentration in the diet required for maximum growth rate, (3) protein intake rate required for maximum growth rate, (4) efficiency of protein retention in growth, and (5) weight of growth achieved per weight of protein ingested. The two animal groups compared differ only in relative protein concentration in the diet required for maximum growth rate. This difference is explained in terms of homeotherms' greater requirement for energy and does not reflect absolute differences in protein requirement. The remaining measures of protein requirement suggest that fishes and terrestrial homeotherms are remarkably similar in their use of protein as a nutritional resource. Reinterpretation of the role of protein in fish physiology, nutrition, and trophic ecology is perhaps in order.

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