Author:
Publisher:
ISBN:
Category : Engineering
Languages : en
Pages : 712
Book Description
Journal of Research of the National Bureau of Standards
Author:
Publisher:
ISBN:
Category : Engineering
Languages : en
Pages : 712
Book Description
Publisher:
ISBN:
Category : Engineering
Languages : en
Pages : 712
Book Description
Minimax Detection Station Placement
Author: Richard D. Smallwood
Publisher:
ISBN:
Category : Mathematical optimization
Languages : en
Pages : 28
Book Description
Publisher:
ISBN:
Category : Mathematical optimization
Languages : en
Pages : 28
Book Description
Earth-to-space Communications at Millimeter Wavelengths
Author: Edward E. Altshuler
Publisher:
ISBN:
Category : Astronautics
Languages : en
Pages : 46
Book Description
It is expected that with the exploration of outer space, a requirement for high data rate earth-to-space communication channels will arise. A program to investigate the feasibility of using the millimeter-wave region of the spectrum for this application is presented. The theory of atmospheric attenuation resulting from losses due to absorption, scattering and refraction processes is reviewed and used to estimate propagation losses produced by atmospheric gases, clouds and precipitation. Curves of total atmospheric attenuation and noise level as a function of meteorological parameters and antenna elevation angle are also presented. A series of experiments designed to obtain as much information as possible on the limitations imposed by the atmosphere on millimeter-wave propagation is considered. Although experiments using natural celestial bodies such as the sun, moon, planets and galaxies as radio sources are emphasized, those which would utilize aircraft, rockets and satellites are also mentioned. Finally, the characteristics of a recently installed precision 29-ft antenna designed to operate at 35 Gc (wavelength = 8.6 mm) with a traveling-wave maser as a preamplifier for the radiometer are outlined along with the specific experiments for which this antenna system will be used. (Author).
Publisher:
ISBN:
Category : Astronautics
Languages : en
Pages : 46
Book Description
It is expected that with the exploration of outer space, a requirement for high data rate earth-to-space communication channels will arise. A program to investigate the feasibility of using the millimeter-wave region of the spectrum for this application is presented. The theory of atmospheric attenuation resulting from losses due to absorption, scattering and refraction processes is reviewed and used to estimate propagation losses produced by atmospheric gases, clouds and precipitation. Curves of total atmospheric attenuation and noise level as a function of meteorological parameters and antenna elevation angle are also presented. A series of experiments designed to obtain as much information as possible on the limitations imposed by the atmosphere on millimeter-wave propagation is considered. Although experiments using natural celestial bodies such as the sun, moon, planets and galaxies as radio sources are emphasized, those which would utilize aircraft, rockets and satellites are also mentioned. Finally, the characteristics of a recently installed precision 29-ft antenna designed to operate at 35 Gc (wavelength = 8.6 mm) with a traveling-wave maser as a preamplifier for the radiometer are outlined along with the specific experiments for which this antenna system will be used. (Author).
Electron-impact Energy Spectra of Acetone and 2-Butanone
Author: S. M. Silverman
Publisher:
ISBN:
Category : Acetone
Languages : en
Pages : 10
Book Description
Publisher:
ISBN:
Category : Acetone
Languages : en
Pages : 10
Book Description
Reflection of Gigacycle-per-second Ultrasonic Waves from an Optical-contact Bond
Author: Paul H. Carr
Publisher:
ISBN:
Category : Acoustics
Languages : en
Pages : 12
Book Description
Publisher:
ISBN:
Category : Acoustics
Languages : en
Pages : 12
Book Description
Ozone Absorption in the 9.0 Micron Region
Author: Shepard Anthony Clough
Publisher:
ISBN:
Category : Hanscom AFB (Mass.)
Languages : en
Pages : 90
Book Description
The absorption of ozone in the 9.0 micron region of the infrared spectrum, due to transitions from the ground state to the v1 and v3 states, has been studied. This report gives the numerical results of an anlysis of the spectrum including transition frequencies and perturbed intensities ordered by quantum number and by frequency. Calculated and observed special contours are included.
Publisher:
ISBN:
Category : Hanscom AFB (Mass.)
Languages : en
Pages : 90
Book Description
The absorption of ozone in the 9.0 micron region of the infrared spectrum, due to transitions from the ground state to the v1 and v3 states, has been studied. This report gives the numerical results of an anlysis of the spectrum including transition frequencies and perturbed intensities ordered by quantum number and by frequency. Calculated and observed special contours are included.
Effects of Experimental Parameters on Thermoluminescence of a Type II-a Diamond
Author: Albert D. Johnson
Publisher:
ISBN:
Category : Crystals
Languages : en
Pages : 42
Book Description
Thermoluminescence provides a method for studying properties of those crystalline imperfections which behave as electron traps and recombination centers in wide bandgap materials. This approach, however, has been used relatively little, possibly due to the fact that the shapes and intensities of thermoluminescent glow curves are functions of several experimental parameters and are often complicated by the overlapping of a number of individual glow peaks. In the present work, experimental parameters were isolated and some of their effects on thermoluminescent glow curves were analyzed. This yielded information on activation energies associated with trapping levels, the nature of the kinetics involved in electron transitions, and electron retrapping. A Type II-a diamond, which has a wide distribution of thermoluminescent glow peaks, was used in this work. (Author).
Publisher:
ISBN:
Category : Crystals
Languages : en
Pages : 42
Book Description
Thermoluminescence provides a method for studying properties of those crystalline imperfections which behave as electron traps and recombination centers in wide bandgap materials. This approach, however, has been used relatively little, possibly due to the fact that the shapes and intensities of thermoluminescent glow curves are functions of several experimental parameters and are often complicated by the overlapping of a number of individual glow peaks. In the present work, experimental parameters were isolated and some of their effects on thermoluminescent glow curves were analyzed. This yielded information on activation energies associated with trapping levels, the nature of the kinetics involved in electron transitions, and electron retrapping. A Type II-a diamond, which has a wide distribution of thermoluminescent glow peaks, was used in this work. (Author).
An Algorithm for the Deformation Method of Quadratic Programming
Author: Roger Even Bove
Publisher:
ISBN:
Category : Algorithms
Languages : en
Pages : 118
Book Description
The following paper represents work to date on the deformation method for quadratic programming and thus may be regarded as a sequel to Zahl, S. (1964) A Deformation Method for Quadratic Programming, Research Note AFCRL-63-132. It gives an explanation of a modified Iverson programming language and uses this to give a detailed algorithm for the Zahl Deformation Method of Quadratic Programming.
Publisher:
ISBN:
Category : Algorithms
Languages : en
Pages : 118
Book Description
The following paper represents work to date on the deformation method for quadratic programming and thus may be regarded as a sequel to Zahl, S. (1964) A Deformation Method for Quadratic Programming, Research Note AFCRL-63-132. It gives an explanation of a modified Iverson programming language and uses this to give a detailed algorithm for the Zahl Deformation Method of Quadratic Programming.
Adsorption of Inorganic Anions on a Mercury Electrode from Solutions of Formamide
Author: Richard Payne
Publisher:
ISBN:
Category : Anions
Languages : en
Pages : 28
Book Description
A theory of hydromagnetic ionizing waves has been developed which is valid in the region in which gas pressure is negligible, compared with magnetic pressure. The theory takes into account the energy expended in partial ionization of the gas behind the wave. The usual high conductivity boundary condition behind the wave is not employed. The electric field in front of the wave is taken as a parameter. Results of this theory are compared with available experimental measurements, and show good agreement. (Author).
Publisher:
ISBN:
Category : Anions
Languages : en
Pages : 28
Book Description
A theory of hydromagnetic ionizing waves has been developed which is valid in the region in which gas pressure is negligible, compared with magnetic pressure. The theory takes into account the energy expended in partial ionization of the gas behind the wave. The usual high conductivity boundary condition behind the wave is not employed. The electric field in front of the wave is taken as a parameter. Results of this theory are compared with available experimental measurements, and show good agreement. (Author).
Nonlinear Terms in the Generalized Ohm's Law
Author: Noel Stone
Publisher:
ISBN:
Category : Electric currents
Languages : en
Pages : 58
Book Description
It is shown that a spatial gradient in the steady flow of an ionized gas introduces terms into the generalized Ohm's law that represent an exchange of momentum between the electrons and the gas flow. Depending upon the flow geometry and gas compressibility this electrokinetic exchange can behave like a generator, a Hall current, or a resistive current. The scale of the phenomenon is L = +/V, where V is fluid velocity, + is electron-positive charge collision time. Electrokinetic conditions apply largely at boundaries. In a resistive medium with a static B-field, the principal condition for electron-flow interchange is that magnetic pressure dominate dynamic pressure. At the boundary of a plasma jet the scale over which EK terms are important is of the order of 1 mm. Only geometry and scale considerations are used in the momentum equation. The electrokinetic generation of surface currents is as fundamental for describing moving media as spacecharge effects are in the static case. (Author).
Publisher:
ISBN:
Category : Electric currents
Languages : en
Pages : 58
Book Description
It is shown that a spatial gradient in the steady flow of an ionized gas introduces terms into the generalized Ohm's law that represent an exchange of momentum between the electrons and the gas flow. Depending upon the flow geometry and gas compressibility this electrokinetic exchange can behave like a generator, a Hall current, or a resistive current. The scale of the phenomenon is L = +/V, where V is fluid velocity, + is electron-positive charge collision time. Electrokinetic conditions apply largely at boundaries. In a resistive medium with a static B-field, the principal condition for electron-flow interchange is that magnetic pressure dominate dynamic pressure. At the boundary of a plasma jet the scale over which EK terms are important is of the order of 1 mm. Only geometry and scale considerations are used in the momentum equation. The electrokinetic generation of surface currents is as fundamental for describing moving media as spacecharge effects are in the static case. (Author).