RADIATION FROM AN ELECTRIC DIPOLE IN A MAGNETOPLASMA

1966 ◽  
Vol 44 (12) ◽  
pp. 3053-3067 ◽  
Author(s):  
S. R. Seshadri
Keyword(s):  
Electric Dipole ◽  
Radiation Resistance ◽  
Numerical Evaluation ◽  
Total Radiation ◽  
Magnetostatic Field ◽  
Azimuthal Mode ◽  
Cylindrical Waves ◽  
Axis Of Symmetry ◽  
The Individual ◽  
Parameters Of Interest

The fields radiated by an arbitrarily oriented electric dipole in an unbounded, loss-free magnetoplasma are synthesized in terms of cylindrical waves, with the direction of the magnetostatic field as their axis of symmetry. Six independent modes specified by two radial and three azimuthal mode numbers are found to be excited. The total radiation resistance of the electric dipole is shown to be obtainable as the superposition of the contributions arising from the individual modes. Integral expressions for the radiation resistance due to the various modes are obtained and are used in the numerical evaluation of the radiation resistance for some typical values of the parameters of interest. The radiation resistance of an arbitrarily oriented electric dipole is found to become infinite in two frequency ranges on account of the gyro- and plasma resonances, as well as at the upper hybrid resonant frequency, and a discussion of the procedure for eliminating the infinite behavior of the radiation resistance is included.

Elimination of Listeria monocytogenes from Ready-to-Eat Turkey and Cheese Tortilla Wraps Using Ionizing Radiation†

2005 ◽  
Vol 68 (1) ◽  
pp. 164-167 ◽  
Author(s):  
CHRISTOPHER H. SOMMERS ◽  
GLENN BOYD
Keyword(s):  
Listeria Monocytogenes ◽  
Radiation Dose ◽  
Ionizing Radiation ◽  
Wheat Flour ◽  
Radiation Resistance ◽  
Meat Product ◽  
Processed Cheese ◽  
Turkey Meat ◽  
Luncheon Meat ◽  
The Individual

Listeria monocytogenes is a common postprocess contaminant on ready-to-eat foods including premade ready-to-eat sandwiches. One popular type of sandwich product is the tortilla wrap, which contains sliced luncheon meats and cheeses rolled within a flour tortilla. This study determined the radiation resistance of L. monocytogenes surface inoculated onto two types of commercially available wheat flour tortillas, processed cheese slices, and deli turkey meat. The D10-values for L. monocytogenes (the radiation dose required to inactivate 1 log of the pathogen) were 0.27 kGy when inoculated onto two flour tortilla types, 0.28 and 0.30 kGy when inoculated onto two types of sliced processed cheeses, and 0.58 and 0.65 kGy when inoculated onto two types of sliced deli turkey meat. When two types of tortilla wraps were assembled from the individual components and L. monocytogenes was inoculated into the interfaces between the individual components, the D10-values were 0.27 to 0.37 kGy in the tortilla and cheese interfaces, 0.33 to 0.41 kGy in the cheese and turkey interfaces, and 0.25 to 0.33 kGy in the turkey and tortilla interfaces. The ability of ionizing radiation to reduce pathogen levels on the complex tortilla, cheese, and luncheon meat product was limited by the higher radiation resistance of L. monocytogenes when inoculated onto the ready-to-eat turkey-meat component.

scholarly journals In situ identification strategy of thermoacoustic stability in annular combustors

2018 ◽  
Vol 10 (4) ◽  
pp. 351-361 ◽  
Author(s):  
Driek Rouwenhorst ◽  
Jakob Hermann ◽  
Wolfgang Polifke
Keyword(s):  
Cylindrical Symmetry ◽  
Mode Shapes ◽  
Stable Operation ◽  
Combustion System ◽  
Azimuthal Mode ◽  
Annular Combustor ◽  
The Moment ◽  
Output Only ◽  
The Individual

In annular combustion systems, thermoacoustic eigenmodes can manifest as standing waves, traveling waves or some form in between. Which dynamic solution appears in a combustor depends on details, regarding the flow field and (unintentional) breaking of the cylindrical symmetry of the annular combustion system. When these details are unknown, the specific behavior cannot be predicted from the characteristics of a single burner. Due to the (nearly) degenerate nature of the acoustic solution, annular eigenmodes come in pairs with practically the same eigenfrequency. In order to identify the thermoacoustic modes, conventional analysis of a spectral peak from a measurement does not suffice, because the peak is a superposition of the two eigenmodes. A method has been proposed to identify the two eigenmodes of given azimuthal mode order from multiple simultaneous measurements around the circumference of the combustion system. Using output-only identification on the acoustic signals, it is possible to estimate the individual mode shapes, frequencies and growth rates of the co-existing eigenmode pair. In this work, the strategy is applied to experimental data from an annular combustor. A split in the growth rate pair is observed during stable operation, depending on the equivalence ratio and flame-to-flame distance. It shows that in situ identification of annular thermoacoustics can reveal subtle dynamic effects, which is useful for testing and online monitoring of annular combustors. The moment when instability occurs can be foreseen under prevailing conditions, with simultaneous identification of the azimuthal mode structure.

On VLF Radiation Resistance of an Electric Dipole in a Cold Magnetoplasma

Radio Science ◽  
1970 ◽  
Vol 5 (3) ◽  
pp. 605-610 ◽  
Author(s):  
T. N. C. Wang ◽  
T. F. Bell
Keyword(s):  
Electric Dipole ◽  
Radiation Resistance

scholarly journals Psychology of ustoychivost': numerical scale for assessing human’s ustoychivost' according to the golden ratio rule

2020 ◽  
Vol 210 ◽  
pp. 20018
Author(s):  
Vyacheslav Kazankov ◽  
Vladimir Gubin
Keyword(s):  
Numerical Evaluation ◽  
Golden Ratio ◽  
Road Map ◽  
Modern Psychology ◽  
Numerical Scale ◽  
Individual Personality ◽  
Ratio Rule ◽  
The Subject ◽  
The Stability ◽  
The Individual

Exploring man, the modern psychology of Europe and America began to actively apply the concepts stability and/or resistance that, in Russia psychology, are combined into one concept — ustoychivost’. In modern psychology, there is no methodology for numerically assessing human ustoychivost’. The article presents the author’s scale of numerical evaluation of ustoychivost ’person and outlines an approach to the formation of its road map. Human ustoychivost ’refers to his ability to maintain health at the psychophysiological, psychological and psychosocial levels of life, forming the unity of the individual, personality and the subject of work in a person. Three hypotheses are put forward. Hypothesis 1: it is possible to numerically establish human ustoychivost ' if you create a scale for assessing it by applying the golden ratio rule — the stability scale for the golden ratio (SUGP). Hypothesis 2: if a person subjectively evaluates his ustoychivost ’in the range from 0.382 to 0.618, then objectively he is stability; if a person subjectively evaluates his ustoychivost ’in the intervals from 0.382 to 0 or from 0.618 to 1, then objectively he is resistance. To test the hypotheses put forward, an experiment on a sample of firefighters is presented, which confirms their fidelity, and also indicates the appropriateness of using SUGP in extreme psychology, labor psychology.

EFFECT OF ION SHEATH ON RADIATION IN A MAGNETOIONIG MEDIUM: II. SOURCE CURRENT PERPENDICULAR TO THE MAGNETOSTATIC FIELD

1967 ◽  
Vol 45 (2) ◽  
pp. 279-299
Author(s):  
S. R. Seshadri ◽  
K. L. Bhatnagar
Keyword(s):  
Radiation Resistance ◽  
Free Space ◽  
Magnetized Plasma ◽  
Magnetostatic Field ◽  
Source Current ◽  
Point Electric Dipole ◽  
Two Peaks ◽  
Limiting Case ◽  
Finite Extent ◽  
A Current

The radiation characteristics of current sources situated along the axis of an infinite cylindrical column of free space and surrounded by a homogeneous, loss-free magnetoionic medium are discussed for the case in which the source current is perpendicular to the magnetostatic field. The static magnetic field is assumed to be parallel to the axis of the free-space column, which is an idealization of the ion sheath formed around the antenna in the ionosphere. Both a point electric dipole and a finite and continuous array of the same are investigated. The dependence of the radiation resistance of these sources on the frequency and the ion-sheath thickness is examined. Even in the limiting case of vanishing thickness of the ion sheath, the radiation resistances of these sources are found to be different from those corresponding to an unbounded plasma. In contrast to those in an unbounded magnetoplasma, the radiation resistance remains finite for all frequencies. For the source of finite extent having a current distribution that falls off sufficiently rapidly towards the ends, the radiation resistance is quite insensitive to the changes in the thickness of the ion sheath.The radiation-resistance curve, in general, has two peaks at the so-called dipolar resonant frequencies, which depend primarily on the strength of the magnetostatic field. These dipolar resonances, which are quite analogous to those in an axially magnetized plasma column, are found to become sharper as the radius of the free-space column becomes smaller.

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