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Gonsalvez, David J. A.On orbital allotments for geostationary satellites /
Doctor of Philosophy, The Ohio State University, 1986, Graduate School

Committee:

Not Provided (Other)

Subjects:

Operations Research

Keywords:

Geostationary satellites;Artificial satellites in telecommunication

Schrello, Dominick MichaelThe effect of aerodynamic torques on the angular motion of an artificial satellite /
Doctor of Philosophy, The Ohio State University, 1960, Graduate School

Committee:

Not Provided (Other)

Subjects:

Engineering

Keywords:

Artificial satellites;Aerodynamics

Chin, Paul B.The attitude motion and stability of a spinning satellite under the influence of the earth's gravity gradient torque /
Doctor of Philosophy, The Ohio State University, 1962, Graduate School

Committee:

Not Provided (Other)

Subjects:

Education

Keywords:

Satellites;Gravity

Reilly, James PatrickStation position determination from correlated satellite observations in the NGS/DOD (BC-4) worldwide network /
Doctor of Philosophy, The Ohio State University, 1974, Graduate School

Committee:

Not Provided (Other)

Subjects:

Education

Keywords:

Geodetic satellites;Azimuth

Papo, Haim BenzionOptimal selenodetic control /
Doctor of Philosophy, The Ohio State University, 1971, Graduate School

Committee:

Not Provided (Other)

Subjects:

Education

Keywords:

Artificial satellites;Selenodesy

Blaha, GeorgesInvestigations of critical configurations for fundamental range networks /
Doctor of Philosophy, The Ohio State University, 1971, Graduate School

Committee:

Not Provided (Other)

Subjects:

Education

Keywords:

Geodesy;Geodetic satellites

Poli, C.A study of the effect of man's motion on the attitude and orbital motion of a satellite /
Doctor of Philosophy, The Ohio State University, 1965, Graduate School

Committee:

Not Provided (Other)

Subjects:

Education

Keywords:

Artificial satellites;Astrodynamics

Selan, Nicholas H.Survivability of Planetary Satellites During Uranus-Neptune Ejection
Master of Science, Miami University, 2008, Physics
Recent work has proposed that the ice giant planets, Uranus and Neptune, did not form where they are located today in the Solar System. Instead, they originated in the present region of the gas giants, Jupiter and Saturn, and then were later gravitationally scattered into highly eccentric orbits that took them out into the Kuiper belt. Interactions with the Kuiper belt objects would slowly circularize their orbits to their present semi-major axes and eccentricities. It is unclear if the ejection process has any effect on systems of planetary satellites that may have existed at this time. We investigate this possibility through a series of simulations that include satellite systems around both the gas giants and the ice giants. For initial conditions, we chose to duplicate those of Tsiganis et al. (2005) where the ejection is caused by a Jupiter/Saturn resonance crossing.

Committee:

Stephen Alexander, PhD (Advisor); S. Douglas Marcum, PhD (Committee Member); Paul DeVries, PhD (Committee Member)

Subjects:

Astrophysics

Keywords:

Uranus; Neptune; Moons; Satellites; Late stage formation

Hayes, ChristopherAnalyzing the performance of new TCP extensions over satellite links
Master of Science (MS), Ohio University, 1997, Electrical Engineering & Computer Science (Engineering and Technology)
It has been shown in Kruse that long delay satellite channels suffer poor throughput using the Transmission Control Protocol, TCP. Performance is limited by the delay inherent in geosynchronous satellites. Several changes have been proposed that could help TCP performance over long delay paths. These changes include big windows and PAWS proposed in RFC 1323, Selective Acknowledgments(SACK), proposed in RFC 2018, Hoe's fast retransmit modifications, and Mathis and Mahdavi's Forward Acknowledgments(FACK). This thesis examines the performance of the new TCP extensions over long delay links. Performance is examined using one, two, and three drop loss events and transfers of various file sizes. This thesis also investigates the performance of the new TCP extensions when encountering varying degrees of bit errors in the satellite channel.

Committee:

Shawn Ostermann (Advisor)

Keywords:

Satellite Channels; Selective Acknowledgments; Geosynchronous Satellites

Yee, Jennifer Chun MingExploring the Extremes of Exoplanet Detection and Characterization in High-Magnification Microlensing Events
Doctor of Philosophy, The Ohio State University, Astronomy
The field of microlensing planet searches is about to enter a new phase in which wide-field surveys will be the dominant mode of planet detection. In addition, there are now plans to execute microlensing surveys from space allowing the technique to reach smaller planets and resolve some of difficulties of ground-based microlensing where the resolution is poor. This new phase of observations also requires a new mode of analysis in which events are analyzed en masse rather than as individuals. Until now, there has not been any investigation into the detection threshold for planets in real data. Some people have suggested that the threshold for detecting planets may be as small as Delta chi^2 of 160, and that is frequently used in microlensing simulations of planet yields. However, no planets have been published with signals that small. I have done the first empirical investigation of the detection threshold for planets in high-magnification microlensing events. I found that MOA-2008-BLG-310 (Delta chi^2=880), MOA-2011-BLG-293 (Delta chi^2=500 without followup data), and MOA-2010-BLG-311 (Delta chi^2=80) form a sequence that spans from detected with high confidence (mb310) to marginally detected (mb293) to something too small to claim with confidence (mb311). This suggests that the detection threshold for planets in high-magnification events is 500 <= Delta chi^2<880. I have also analyzed OGLE-2008-BLG-279 to determine the range of planets that are detectable for this event given the excellent data quality and the high-magnification. This event illustrates that high-magnification events will still be important in the era of surveys because each event is much more sensitive to planets than any individual low-magnification event. Because they probe the central caustics, high-magnification events are sensitive to planets at any angle, meaning that they place more stringent limits on the presence of planets. For this event, Jupiter-mass companions can be ruled out from 0.5-20 AU. As the field extends to new modes of observations, it is worth considering how we can maximize the information we can obtain for each microlensing event, particularly given the limitation that microlensing is primarily sensitive to mass ratio rather than planet mass. I propose a means to take advantage of the excellent light curves that will be available from space and combine them with ground-based observations to measure microlens parallax for a large fraction of the microlensing events that will be seen by a space-based microlensing survey. This measurement will enable the measurement of the planet masses for these events.

Committee:

Andrew Gould (Advisor); B. Scott Gaudi (Committee Member); Richard Pogge (Committee Member)

Subjects:

Astronomy; Astrophysics

Keywords:

gravitational lensing - micro; planets and satellites - detection; microlensing; planets

Kumar, MuneendraMonitoring of crustal movements in the San Andreas fault zone by a satellite-borne ranging system /
Doctor of Philosophy, The Ohio State University, 1976, Graduate School

Committee:

Not Provided (Other)

Subjects:

Education

Keywords:

Geodetic satellites;San Andreas Fault

Van Gelder, Boudewijn Hendricus W.Estimability and simple dynamical analyses of range (range-rate and range-difference) observations to artificial satellites /
Doctor of Philosophy, The Ohio State University, 1978, Graduate School

Committee:

Not Provided (Other)

Subjects:

Education

Keywords:

Artificial satellites

SYED, ANEESCOLLISON PREDICTION AND AVOIDANCE OF SATELLITES IN FORMATION
MS, University of Cincinnati, 2004, Engineering : Mechanical Engineering
Satellites flying in formation has been the focus of current research. Sometimes,there are issues with the amount of information available about the satellites. Due to hardware limitations, full measurements of relative positions and velocities of the spacecraft may not be available. In the long-term, the only information available might be the inter-satellite ranges between the satellites. The first part of the present work aims at the reconstruction of the trajectory of a satellite from this limited information, i.e., the time history of inter-satellite range. The present work deals with the case of three satellites in formation. One satellite is at the reference in a near circular orbit and the other two satellites trace Hill’s orbits relative to the reference. The geometry and phasing of one satellite is assumed to be known and the trajectory parameters of the other satellite relative to the reference are computed. Due to atmospheric drag there is a possibility that one of the satellites may drift and slip out of the formation. This may lead to a collision between the two satellites which might damage any appendages on the spacecraft like the antennas. The objective of the second part of the thesis is to devise a strategy to avoid the collision. The solution from the first part will be used to predict a possible collision in the future and a suitable thrusting technique will be applied to avoid the collision. The only collision scenario considered, in the present work, is 'tangential orbits'.

Committee:

Dr. David Thompson (Advisor)

Keywords:

satellites; satellite formations; formation control; orbital mechanics

Obenson, Gabriel Francis TambeDirect evaluation of the earth's gravity anomaly field from orbital analysis of artificial earth satellites /
Doctor of Philosophy, The Ohio State University, 1970, Graduate School

Committee:

Not Provided (Other)

Subjects:

Geophysics

Keywords:

Gravity anomalies;Gravity;Artificial satellites;Satellite geodesy

Barritt, Brian JamesThe Modeling, Simulation, and Operational Control of Aerospace Communication Networks
Doctor of Philosophy, Case Western Reserve University, 2017, EECS - Computer Engineering
A paradigm shift is taking place in aerospace communications. Traditionally, aerospace systems have relied upon circuit switched communications; geostationary communications satellites act as bent-pipe transponders and are not burdened with packet processing and the complexity of mobility in the network topology. But factors such as growing mission complexity and NewSpace development practices are driving the rapid adoption of packet-based network protocols in aerospace networks. Meanwhile, several new aerospace networks are being designed to provide either low latency, high-resolution imaging or low-latency Internet access while operating in non-geostationary orbits -- or even lower, in the upper atmosphere. The need for high data-rate communications in these networks is simultaneously driving greater reliance on beamforming, directionality, and narrow beamwidths in RF communications and free-space optical communications. This dissertation explores the challenges and offers novel solutions in the modeling, simulation, and operational control of these new aerospace networks. In the concept, design, and development phases of such networks, the dissertation motivates the use of network simulators to model network protocols and network application traffic instead of relying solely on link budget calculations. It also contributes a new approach to network simulation that can integrate with spatial temporal information systems for high-fidelity modeling of time-dynamic geometry, antenna gain patterns, and wireless signal propagation in the physical layer. And towards the operational control of such networks, the dissertation introduces Temporospatial Software Defined Networking (TS-SDN), a new approach that leverages predictability in the propagated motion of platforms and high-fidelity wireless link modeling to build a holistic, predictive view of the accessible network topology and provides SDN applications with the ability to optimize the network topology and routing through the direct expression of network behavior and requirements. This is complemented by enhancements to the southbound interface to support synchronized future enactment of state changes in order to tolerate varying delay and disruption in the control plane. A high-level overview of an implementation of Temporospatial SDN at Alphabet is included. The dissertation also describes and demonstrates the benefits of the application of TS-SDN in Low Earth Orbiting (LEO) satellite constellations and High Altitude Platform Systems (HAPS).

Committee:

Frank Merat (Committee Chair); Rabinovich Michael (Committee Member); Daniel Saab (Committee Member); Mark Allman (Committee Member)

Subjects:

Aerospace Engineering; Computer Engineering; Computer Science

Keywords:

temporospatial; SDN; TS-SDN; aerospace; networks; satellites; LEO; NGSO; constellations; HAPS; high-altitude platforms; STK; wireless; mesh; networking; modeling; simulation; ns-3

Devasirvatham, Daniel Manoharan JothirajEffects of atomospheric turbulence on microwave and milimeter wave satellite communications systems /
Doctor of Philosophy, The Ohio State University, 1981, Graduate School

Committee:

Not Provided (Other)

Subjects:

Engineering

Keywords:

Artificial satellites in telecommunication;Atmospheric turbulence

Cortes, MichaelSymphony No. 1 “The Galilean Satellites”
MM, University of Cincinnati, 2010, College-Conservatory of Music : Composition
Symphony No. 1 "The Galilean Satellites" was written from 2008 to 2009. These four moons, discovered in 1610 by Galileo Galilee are very unique objects in our solar system. Europa is one of the smoothest objects in the solar system and has the best chance of containing possible life. Ganymede is the largest moon in the solar system and to this point is the only moon that has its own magnetic field. Io is one of the most geologically active objects in the solar system and contains many volcanoes. Callisto is one of the most heavily cratered objects in the entire solar system. As you can tell, each of these moons is very different so I wanted to try to make each movement unique on its own, but at the same time I felt it was important to do something to unify all of the movements together somehow because these moons, although very different from each other, are all part of the great discovery of Galileo Galilee. In addition, Europa, Ganymede, and Callisto are all believed to contain a liquid ocean beneath their surface. When listening to the music, a very familiar slow motive will play, which is my portrayal of the possibility of life. At the very end of the entire work, you will hear ideas/motives from all of the previous movements. The electronics in this piece use not only software synthesizers and edited sounds created in MAX/MSP, but there are real sounds taken from NASA that was actually recorded through data received from space equipment that were visiting these moons from outer space.

Committee:

Mara Helmuth, DMA (Committee Chair); Mike Fiday, PhD (Committee Member); Joel Hoffman, DMA (Committee Member)

Subjects:

Music

Keywords:

Symphony; Galilean Satellites; pipe organ; band; moons

Engelis, TheodossiosRadial orbit error reduction and sea surface topography determination using satellite altimetry /
Doctor of Philosophy, The Ohio State University, 1987, Graduate School

Committee:

Not Provided (Other)

Subjects:

Education

Keywords:

Artificial satellites;Sea level;Altimeter

Wichiencharoen, ChugiatRecovery of 1⁰-mean anomalies in a local region from a low-low satellite to satellite tracking mission /
Doctor of Philosophy, The Ohio State University, 1985, Graduate School

Committee:

Not Provided (Other)

Subjects:

Education

Keywords:

Gravity;Geodetic satellites

Wintz, Edward KennaGeometric applications of artificial earth satellite observations /
Doctor of Philosophy, The Ohio State University, 1965, Graduate School

Committee:

Not Provided (Other)

Subjects:

Physics

Keywords:

Artificial satellites

Knipling, Louis HenryThe metric cartographic potential of geostationary/geosynchronous satellites /
Doctor of Philosophy, The Ohio State University, 1973, Graduate School

Committee:

Not Provided (Other)

Subjects:

Education

Keywords:

Artificial satellites in geographical research;Cartography

Wang, Cou-wayOptimization of orbital assignment and specification of service areas in satellite communications /
Doctor of Philosophy, The Ohio State University, 1986, Graduate School

Committee:

Not Provided (Other)

Subjects:

Engineering

Keywords:

Artificial satellites in telecommunication

Pavlis, Erricos C.On the geodetic applications of simultaneous range-differencing to Lageos /
Doctor of Philosophy, The Ohio State University, 1983, Graduate School

Committee:

Not Provided (Other)

Subjects:

Education

Keywords:

Geodetic satellites

Kennedy, James ClarenceGravity gradient effects on some of the basic stability requirements for an orbiting satellite having long flexible antennae /
Doctor of Philosophy, The Ohio State University, 1967, Graduate School

Committee:

Not Provided (Other)

Subjects:

Education

Keywords:

Artificial satellites;Antennas ;Gravity gradient booms

Moussa, Osama MoursySatellite data based sediment-yield models for the Blue Nile and the Atbara River Watersheds /
Doctor of Philosophy, The Ohio State University, 1987, Graduate School

Committee:

Not Provided (Other)

Subjects:

Engineering

Keywords:

Remote sensing;Earth resources technology satellites;Blue Nile River Watershed;Atbara River Watershed

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