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Articles 8851 - 8880 of 9199
Full-Text Articles in Physical Sciences and Mathematics
Plasma Sheath Analysis By Computer Simulation, Leo J. Rahal
Plasma Sheath Analysis By Computer Simulation, Leo J. Rahal
Physics & Astronomy ETDs
The time development of a fully ionized, dense two-component plasma is investigated through the use of a one-dimensional particle simulation code. The plasma is initially composed of two distinct regions. One region is a uniform plasma in which electrons and ions are at the sane temperature and have no electric fields due to charge separation. The other region contains a charge separation of electrons and ions resulting in an electric field. There also exists an electron current which produces a confining magnetic field. This is the sheath region between the neutral plasma and the confining magnetic field. The simulation occurs …
Infrared Observations Of Hii Regions And Comet West, Paul A. Heckert
Infrared Observations Of Hii Regions And Comet West, Paul A. Heckert
Physics & Astronomy ETDs
In Chapter 1, I outline the methods of making ground-based infrared observations. I concentrate on the observational procedures rather than the instrumental design. Near-infrared observations of S 156A, _S 158A, S 159A, S 162A1, S 228, and G 45. 5 + 0 .1 (#2) made with a beam size of ̴1 are used to estimate the total near infrared flux. After correcting for the line of sight extinction the near infrared luminosities are greater than the Lyman-α luminosities inferred from radio observations. A strong double peaked infrared source was discovered near the region of G 25.3-0.1. The infrared …
¿Dónde Está El Límite Del Universo?, Aldemaro Romero Jr.
¿Dónde Está El Límite Del Universo?, Aldemaro Romero Jr.
Publications and Research
No abstract provided.
El Viento De Las Estrellas, Aldemaro Romero Jr.
El Viento De Las Estrellas, Aldemaro Romero Jr.
Publications and Research
No abstract provided.
The Nitrogen Dayglow On Mars, Jane L. Fox, Alexander Dalgarno, E. R. Constantinides, G. A. Victor
The Nitrogen Dayglow On Mars, Jane L. Fox, Alexander Dalgarno, E. R. Constantinides, G. A. Victor
Physics Faculty Publications
The ultraviolet dayglow spectrum arising from emission of N2 in the Mars atmosphere is predicted. The intensities are such that a high-resolution spectrum should readily reveal the presence of N2 at the abundances suggested by the Viking experiments.
Solar Magnetoatmospheric Waves-A Simplified Mathematical Treatment, John A. Adam
Solar Magnetoatmospheric Waves-A Simplified Mathematical Treatment, John A. Adam
Mathematics & Statistics Faculty Publications
The inhomogeneous wave equation for a special class of magnetoatmospheric waves is formally solved, and the principle of stationary phase used to provide information on the group velocity properties of such waves. General results are presented concerning the associated mechanical energy flux. The basic problem considered is relevant to waves initiated by sudden events in the solar atmosphere.
Computer Model Of A Fast Toroidal Plasma Compression, With Application To The Topolotron, H. Mark Nelson, Keith H. Brown, Charles A. Hart
Computer Model Of A Fast Toroidal Plasma Compression, With Application To The Topolotron, H. Mark Nelson, Keith H. Brown, Charles A. Hart
Faculty Publications
The method is developed for a comuputer sequence which models a fast toroidal theta or screw pinch for a highly conducting axially symmetric plasma. The computer sequence takes into account the self-inductances of the plasma and the external conductors which drive the compression as well as the mutual inductance which electromagnetically couples the two. The computer sequence is divided into three phases: a snowplow compression phase, an adiabatic compression phase, and a crowbarred circuit phase. The computer sequence is applied to a topolotron and an example is given of a magnetohydrodynamic equilibrium geometry for which the plasma surface possesses an …
Behavior Of A Manganin Coil At Elevated Temperatures And Pressures, Jonathan D. Weiss, Daniel L. Decker, H. B. Vanfleet
Behavior Of A Manganin Coil At Elevated Temperatures And Pressures, Jonathan D. Weiss, Daniel L. Decker, H. B. Vanfleet
Faculty Publications
We have determined the temperature dependence in the first-order pressure coefficient of a manganin coil to be dBetaB/dT= (4.2±0.8) ×10^-7 (kbar degrees C)^-1 in the equation R (T,P) =R (T,0)(1+BetaP+GammaP2), where R (T,P) is the coil resistance at temperature T and pressure P. The measurements were performed by simultaneously measuring the coil resistance and temperature at the transitions of mercury and bismuth, which were observed by differential thermal analysis.
Ultraviolet Radiation Effects On Rotifers, Syed Asim Hussain
Ultraviolet Radiation Effects On Rotifers, Syed Asim Hussain
Masters Theses & Specialist Projects
The purpose of this investigation was to study ultraviolet radiation effects on rotifers. The rotifer studied was Philodina acuticornis odiosa Milne. Isolation cultures were used to grow the rotifers individually in separate U-plate depressions. The source of ultraviolet radiation consisted of four mercury germicidal lamps used in combination to deliver a uniform flux of 315 uW/cm2 over the sample. Five groups of rotifers, one control and four experimental groups of 96 each, were used. The rotifers used were 2-10 hours of age at the beginning of the experiment. The experimental groups were exposed to uv radiation for 3 minutes, …
"The Search For Extra-Terrestrial Life", Donald L. Devincenzi
"The Search For Extra-Terrestrial Life", Donald L. Devincenzi
Special Collections: Oregon Public Speakers
No abstract provided.
Sensitivity Of A Gas Filter Correlation Instrument To Variations In Atmospheric Profile And Earth Surface Temperatures, Joseph C. Casas
Sensitivity Of A Gas Filter Correlation Instrument To Variations In Atmospheric Profile And Earth Surface Temperatures, Joseph C. Casas
Physics Theses & Dissertations
The Gas Filter Correlation Radiometer Analyzer (GFCR), in application to the remote sensing of trace gases in the atmosphere, is potentially limited by the sensitivity of the measured upwelling thermal radiation to surface temperature and atmospheric temperature conditions. This study has been carried out to examine the principles of operation of the GFCR Analyzer and to obtain quantitative estimates of the errors produced in GFCR Analyzer measurements of CO (4.6μ), S02 (8.6μ), NH3 (11.0μ), and CH4 (8.1μ) resulting from uncertainties in the atmospheric temperature profile and ground temperature.
A simple mathematical prototype GFCR Analyzer was assumed. A line-by-line atmospheric radiative …
The Determination Of Double Mode Variable Star Periods, Arne A. Henden
The Determination Of Double Mode Variable Star Periods, Arne A. Henden
Physics & Astronomy ETDs
ABSTRACT
The problem of determining the periods of objects oscillating in one or more modes is discussed. Although the methods described are applicable to many different kinds of objects and observations, the discussion has been limited to double mode Cepheid stars.
Two methods of solution are followed in detail. An autocorrelation technique based on the scatter of points in an amplitude-phase plane is used for most cases. A means of calculating smoothed mean curves is discussed. A Fourier transform method is presented for closely spaced data points, with prewhitening included for accurate secondary period and amplitude determinations.
Three test problems …
Gravitational Motion: An Interaction?, Frank H. Meyer
Gravitational Motion: An Interaction?, Frank H. Meyer
Journal of the Minnesota Academy of Science
"Non-implications" in Newton's Law of Gravitation are discussed to emphasize different approaches in two books treating the subject: Dewey Larson's Beyond Newton, and Gravitation, by Misner, Thorne and Wheeler. The author notes that the latter book ignores the possibility that gravitation may not be an interaction; while Larson accepts Newton's Law of Gravitation as a mathematically valid statement of Kepler's Laws of Planetary Motion, thus being applicable to the sun and planets even if they are not actually interacting.
Una Roca Lunar En Barcelona, Aldemaro Romero Jr.
Una Roca Lunar En Barcelona, Aldemaro Romero Jr.
Publications and Research
No abstract provided.
Pole Stars Of Other Planets, Paul C. Sharrah
Pole Stars Of Other Planets, Paul C. Sharrah
Journal of the Arkansas Academy of Science
The north celestial pole of the Earth and the other planets is discussed. Right ascension and declination information on the location of the poles on the celestial sphere is summarized. The name of the brightest visible star near each pole is given and the special case of Uranus is discussed.
Thermal Instability In Supernova Shells, R. Mccray, R. F. Stein, Menas Kafatos
Thermal Instability In Supernova Shells, R. Mccray, R. F. Stein, Menas Kafatos
Mathematics, Physics, and Computer Science Faculty Articles and Research
Thermal instability in the radiative cooling region behind a shock will cause upstream density fluctuations to collapse into thin sheets aligned parallel to the shock front. A linearized calculation demonstrates the development of this instability. Thermal conduction suppresses the development of small-scale perturbations. Estimates of the scale sizes for the fully developed condensations agree roughly with the scale sizes of fine structure observed in supernova shells such as the Cygnus Loop.
Sources Of Excitation Of The Interstellar Gas And Galactic Structure, J. J. Cowan, Menas Kafatos, W. K. Rose
Sources Of Excitation Of The Interstellar Gas And Galactic Structure, J. J. Cowan, Menas Kafatos, W. K. Rose
Mathematics, Physics, and Computer Science Faculty Articles and Research
The excitation of the interstellar gas. is discussed in the light of recent evidence from γ-ray, molecular, and 21-cm line observations. Previous studies of the excitation of the interstellar gas have not taken into account the substantial density contrast that exists between spiral arms and interarm regions. We examine the role played by the galactic distribution of three sources of excitation (supernovae, OB stars, and ultraviolet stars) in determining the physical state of the interstellar gas in arm and interarm regions.
E.S.A., N.A.S.A. Europea…, Aldemaro Romero Jr.
E.S.A., N.A.S.A. Europea…, Aldemaro Romero Jr.
Publications and Research
No abstract provided.
Christian Astronomy Vs. Secular Astronomy, Richard G. Hodgson
Christian Astronomy Vs. Secular Astronomy, Richard G. Hodgson
Pro Rege
No abstract provided.
General Geodesic Motion In The Extended Kerr Manifold, Richard H. St. John
General Geodesic Motion In The Extended Kerr Manifold, Richard H. St. John
Physics & Astronomy ETDs
The timelike and null geodesics in the Kerr metric describe important properties of the space surrounding a rotating black hole. The general characteristics of these geodesics, with an emphasis on those on the axis of symmetry and the equatorial plane, are found in this paper. On the axis of symmetry, the behavior of all timelike and null geodesics is completely described. The accessibility of various spaces added for geodesic completeness in the extended manifold is found by making local observations of geodesics in one coordinate patch from geodesics in another. The analysis on the equatorial plane shows that for a …
Ultraviolet Photosimulated Thermoluminescence Of Lithium Flouride, Martin Payne
Ultraviolet Photosimulated Thermoluminescence Of Lithium Flouride, Martin Payne
Masters Theses & Specialist Projects
TLD-100 (lithium fluoride) thermoluminescence dosimeters are widely employed for the detection of ionizing radiations. This paper shows that these dosimeters may also serve as practical germicidal ultraviolet radiation dosimeters. To measure ultraviolet radiation, the TLD-100 dosimeters are first exposed to 500,000 roentgens of gamma radiation and then annealed at 300°C. Subsequent dosage of ultraviolet radiation may be determined by observation of photostimulated thermoluminescence of the crystal. The presented data indicate that the thermoluminescence response is linear for exposures up to 6,000 µjoule/cm2 and independent of exposure rate from 0.1 µ watt/cm2 to above 50 µwatt/cm2. Optical …
A Method For Measuring The Electrical Conductivity Of A Shocked Liquid, Richard James Hassman
A Method For Measuring The Electrical Conductivity Of A Shocked Liquid, Richard James Hassman
Physics & Astronomy ETDs
Development of a simple technique for the measurement of the gross electrical conductivity of a shock compressed liquid is attempted. A cell containing the sample is constructed from glass cylinders and aluminum foil. The foil is sandwiched between two cylinders of the same diameter to form a two compartment cylinder. The cylinder is mounted on a metal target plate. With both chambers of the system full of liquid, only insignificant reflections can arise from the sample-foil interface. A voltage is placed across the cell between the foil and the target plate, and the change in voltage as the shock front …
Hand Held Probe For Use In Electrical Sensing Of Plane Coordinates, George S. Hurst
Hand Held Probe For Use In Electrical Sensing Of Plane Coordinates, George S. Hurst
Physics and Astronomy Faculty Patents
A probe with a puncturing, electrically conducting needle is constructed to enable the user, whether right or left handed, to position the needle rapidly and accurately at a selected coordinate of a sensor package.
Ua77/1 Western Alumnus, Vol. 43, No. 4, Wku Alumni Association
Ua77/1 Western Alumnus, Vol. 43, No. 4, Wku Alumni Association
WKU Archives Records
WKU alumni magazine. Features the following articles:
- Conway, Sheila. Competency Based Teacher Education
- Scarborough, John. Enthusiasm & Planning, Powerful One-Two Punch for Education
- Burkeen, Emmett. Counselor Education, A Study in Development
- Stuart, Robert. The Stage is His Classroom - Bill Leonard
- Just, Paul. Remember When, 1955-56
- Conway, Sheila. Women's Athletics Return
- Armstrong, Don. Biology for Real - Tech Aqua Biological Station
- Goldwater, Barry. On the Energy Crisis
- Porter, William. Third World Realities
- Muskie, Edmund. Restoring Our Confidence
- Dickey, Debbie. The Big Red Western Band
- Given, Ed. Instant Alumni
- Topper Power Carries WKU to National Finals - Football
- Jimmy Feix, Coach …
Theories On Planetary Motions, Jerry Thomason
Theories On Planetary Motions, Jerry Thomason
Honors Theses
Anyone who has gazed into the starry sky with awe and amazement has often wondered what holds things together, where space ends and if there is no end, what wonders are beyond. The planets that are contained in this solar system and the growth of theories of the causes of the motions of these bodies are just some of the many wonders that a person can research.
In this work, I have intended to trace more or less a history of man's theories that govern the motions of the planets. I must admit that I will not cover by far …
Mercurio: El Redescubrimiento De Un Planeta, Aldemaro Romero Jr.
Mercurio: El Redescubrimiento De Un Planeta, Aldemaro Romero Jr.
Publications and Research
No abstract provided.
Júpiter: Sencillamente Fantástico, Aldemaro Romero Jr.
Júpiter: Sencillamente Fantástico, Aldemaro Romero Jr.
Publications and Research
No abstract provided.
El Instituto Nacional De Técnica Aeroespacial, Un Ejemplo De Muchas Cosas, Aldemaro Romero Jr.
El Instituto Nacional De Técnica Aeroespacial, Un Ejemplo De Muchas Cosas, Aldemaro Romero Jr.
Publications and Research
No abstract provided.
Nubes De Moléculas Orgánicas En El Espacio, Aldemaro Romero Jr.
Nubes De Moléculas Orgánicas En El Espacio, Aldemaro Romero Jr.
Publications and Research
No abstract provided.
Twenty Years Of Experience With The University Of Arkansas Planetarium, Paul C. Sharrah
Twenty Years Of Experience With The University Of Arkansas Planetarium, Paul C. Sharrah
Journal of the Arkansas Academy of Science
The Model A-1 Spitz planetarium was placed in operation at the University of Arkansas in 1954. It was moved to its present location in 1972 and has continued to have a much expanded use. More than 8,000 persons attended demonstrations between 1 August 1972 and 31 March 1974. Approximately one third of these were University students in classes and laboratories; the remaining two thirds were accounted for by school and other youth groups and the public demonstrations.