Digital Commons Network^™

Insurance Issues For Small Satellites And Elvs, Peter Stark

Small Satellite Conference

This paper is intended to identify to those considering the use of small satellites and expendable launch vehicles the issues which may affect their ability to obtain insurance for their activities. It first discusses the types of insurance which are presently associated with space activities, including physical damage and liability coverages. It then addresses those aspects of small satellites and ELVs which appear to be different than present insurable space activities, and concludes by discussing how those differences might affect insurance requirements.

A Design Template For Gas Satellite Payloads, Daniel Sakoda

Small Satellite Conference

The Naval Postgraduate School has designed a small, low cost, general purpose satellite bus, ORION. An investigation of the structural requirements has been done for ORION as an extended Get Away Special (GAS) canister payload. The structure must be able to withstand the design limit load of 6.0 g's acceleration in ± X and ± Y, and a limit load of 10.0 g's in the ± Z. The structure must also have modal vibration greater than 35 Hz. A finite element analysis in linear bending considers an aluminum stiffened cylinder with two equipment plates and a top plate. Considerable weight …

Packet Store-And-Forward Communications Satellites For Relief And Development, Gary Garriott

Small Satellite Conference

The early history of proposed small satellites in low earth orbit using store-and-forward digital technology for humanitarian relief and development work is reviewed. A description of the current status of the PACSAT project being developed jointly by SST Ltd and VITA is is provided. The need to decrease the turnaround period of time-dependent technical information to and from isolated regions of the world is described, as well as limitations to project success when the right information is not available at the right time. Major PACSAT applications areas in relief and development are presented, and a functional description of several tiers …

A Framework For Analyzing The Market And Supporting Infrastructure For Small Satellites And Associated Systems, Stephen Morgan

Small Satellite Conference

A comprehensive, conceptual framework within which space programs, projects, and activities can be analyzed is presented. This framework consists of a number of largely functional dimensions. Most important is the division of space-based and space-oriented activity into two major segments: the space infrastructure, and space-derived products and services. The space infrastructure includes the various functions and devices which support space-oriented activity, including launch vehicles, payload and vehicle processing facilities plus those organizational and technological elements which support space-oriented activity, including the institutional support base. Space-derived products and services are those products and services which can only be produced within the …

Uogas - A Get Away Special Satellite With Orbit-Raising Capability, Ralph Lorenz

Small Satellite Conference

The low cost of satellite deployment from Shuttle GAS canister makes it an attractive launch option. However, the low deployment altitude severely constrains lifetime so the UoGAS (University of Surrey Get Away Special) spacecraft will incorporate a propulsion system. Lifetime extension methods are considered and a start-of-mission orbit-raising manoeuvre is selected. An orbit dynamics simulation method (taking into account the atmospheric drag) is discussed and results presented. Mission profiles, propulsion systems (including colloid, resistojet and cold gas thrusters, as well as a novel hybrid bipropellant combination) and stabilisation options are discussed: an aerodynamically stabilised vehicle with a resistojet propulsion system …

International Small Satellite Organization; Connecting The Small Space Systems Community, R. Fleeter

Small Satellite Conference

ISSO (International Small Satellite Organization) connects the diverse members of the low cost space systems community. The bimonthly ISSO newsletter, related ISSO activities, membership and membership services are described. The role of ISSO in the emerging small satellite/launcher industry and ISSO plans for 1989 are discussed. ISSO’s first 18 months and some publication highlights are reviewed.

Preliminary Design And Concept Of Operations For A Small Tactical Imaging Satellite, Neal Miller, Larry Chizek

Small Satellite Conference

Tactical commanders could use a reconnaissance satellite which is survivable, flexible in operations, and able to provide real time direct data of high quality imagery. By design, the imaging satellite would be inexpensive and mutually beneficial to all the armed services. The imaging satellite is solar powered and 3 axis stabilized. A constellation of satellites in sun synchronous orbits will provide near worldwide coverage with revisit times of 90 minutes. Command and control will come from a single field unit, although many units may have receive capability. The satellite could be used during times of crisis or stored for future …

Active Magnetic Control System For Gravity Gradient Stabilized Spacecraft, Francois Martel, Parimal Pal, Mark Psiaki

Small Satellite Conference

Active magnetic control is studied as a means to improve the capabilities and performance of gravity gradient stabilized spacecraft. Active magnetic control eliminates the need for a passive damper and can reduce significantly the costs and complexity of other functional parts of the spacecraft. The system under study includes three magnetic torquers, one three-axis magnetometer, and a control processor. It does not require any moving parts, and provides for rapid libration damping, tighter stabilization and active control of the yaw angle. Control algorithms are defined. Results of the analysis of the control laws and computer simulations, including high-order models of …

Operation Of A Small Tethered Payload, Peter Banks, Roger Williamson, Thomas Vaneck, Burt Lee, Eric Stoneking

Small Satellite Conference

This paper presents results of a study currently being performed at Stanford University sponsored by NASA/Goddard Space Station Small Attached Payloads. The use of tethers as a means of dynamic isolation for small attached payloads shows promise in reducing orbital maneuvering vehicle requirements to service co-orbiting facilities while still providing a stable contamination-free platform for precision pointing instruments. Thethers may also be used as a means of deorbiting small sample return vehicles. These return vehicles might be dedicated small experiment carriers for a specific mission and require little manned interaction, or they might be loaded with experimental samples for de-orbit …

Observations Of Single-Event Memory Upsets On The Uosat-2 Satellite, Jeff Ward

Small Satellite Conference

This paper describes observations of single-event memory upsets in the UoSAT-2 satellite Digital Communications Experiment. Two years of SEU observations for Harris 6564 memories are included, presented both as error rate statistics and as a map of satellite orbital location at the time of error occurrence. The results presented here are the preliminary observations in a long-term single-event upset study funded by ESA-ESTEC.

Design Of A Small Satellite For Use In Astronautics Education, Walter Daniel

Small Satellite Conference

The Naval Academy is pursuing a small satellite project to give midshipmen hardware and ground control experience. The concept is for a lightweight, gravity-gradient stabilized satellite to be deployed from a Get Away Special cannister; the payload would be two small, low-resolution imagers (one visible and one infrared). The 40 foot diameter ground station antenna being installed at the Naval Academy can receive a power of 10 milliwatts from a satellite that uses an omnidirectional antenna and is in a typical Space Shuttle orbit. Approximately 5 to 7 watts of power is constantly available to the payload of up to …

Development Of A Responsive Small Spacecraft, P.A. Miller, C.A. Hughes

Small Satellite Conference

The development of a small spacecraft bus is presented. The approach applied seeks to respond to the requirements of potential users as represented by a large data base of payload missions, while minimizing cost. The development results in a general purpose spacecraft design that is responsive to a wide range of mission requirements, and provides a clear definition of capabilities and interfaces to facilitate user mission design.

A Modular Small Satellite Bus For Low Earth Orbit Missions, N.P. Bean

Small Satellite Conference

The University of Surrey has demonstrated its capability in the field of small, low-cost spacecraft with the UoSAT-1 and 2 missions launched into low earth orbit in 1981 and 1984. Surrey Satellite Technology Ltd., a company formed by the University of Surrey, is now developing a flexible spacecraft bus based on the experience gained from these missions. The paper describes how the design philosophy used on the UoSAT spacecraft has been advanced to produce a bus providing basic power conditioning, telecommand, telemetry and attitude control functions. This basic bus is sufficient to support a variety of payloads, but the architecture …

The Italian Approach To Small Satellites For Low Cost Access To Space Developments, G. Rondinelli, G. Barresi, A. Cramarossa, F. Graziani

Small Satellite Conference

Several technological institutions and scientific center are presently forbidden to access space exploration, because of the high costs involved with satellite development and launch. ITALSPAZIO has performed several studies directed toward the minimization of such costs. Possible design approaches are: use of a small bus capable to fly at marginal cost on expendable launch vehicles by paying delta-costs when passing from one launcher class to the upper next of the same launcher, (an example is constituted by the ARIANE IV when passing from AIRANE 40 to ARIANE 42s); use of left-over launcher capacities; use of subsystems and equipment’s developed for …

The Avatar Small Spacecraft System, Joseph Leblanc

Small Satellite Conference

American Microsat president Joseph A. LeBlanc will present the AVATAR Small Spacecraft System. The AVATAR Small Spacecraft System consists of the AVATAR satellite modules and the ground control and data collection facility. The AVATAR spacecraft is comprised of modules containing specific mission subsystems that are designed to work together or independently to satisfy mission requirements. Four modules provide payload space, control, propulsion and three axis stabilization. The different modules (described below) and the customer launch options will be discussed separately during the presentation. Common Services Module: The Common Services Module houses the spacecraft computer, the TT&C communications equipment, the attitude …

Deep Space Missions For Small Satellites, Paula Butler, Alan Stein

Small Satellite Conference

Small satellites, with masses well under 100 kg, can perform useful deep space science missions for costs similar to those of low earth orbit and geosynchronous smallsats. Space Explorations has identified several interesting missions for smallsats, with the objective of developing "turnkey" space-science packages which would have a cost to the customer of $10,000,000 and be operable by one or a few people. We have analyzed one mission, a Lunar Polar Photographic Orbiter, in great detail over the last year. We conclude that it is commercially and scientifically feasible to produce a small lunar satellite which is capable of doing …

Orbital Payload Recovery, Roland Mayer

Small Satellite Conference

The growing focus on orbital manufacture and associated experimentation highlights an increasing need for reliable, low cost recovery of orbital payloads. Simplistic recovery operations and vehicles designed for refurbishment and reuse can provide this desired economy. Based on prior operational experience and present conceptional thinking both are immediately feasible. With the accelerated commercial booster development now in progress, the operational facets of such programs remain the only significant cost elements still requiring definition and resolution. This paper will describe the range of vehicles anticipated for such operations, the economies effecting their operation and restrictions and limitations they impose on planned …

The Uosat-C,D & E Technology Demonstration Satellites, N.P. Bean, J.M. Radbone, M.N. Sweeting, J.W. Ward

Small Satellite Conference

The University of Surrey (UK) planned a small, inexpensive spacecraft (UoSAT-C) to be launched by NASA on a DELTA launch vehicle as a secondary payload into low-Earth orbit in 1989. This launch has been postponed, but the University has obtained two launch slots on ARIANE. Two spacecraft, UoSATs D & E are currently under construction at The UoSAT Spacecraft Engineering Research Unit at Surrey and they involve collaboration with international experimenters. The spacecraft will carry the majority of the payloads from the postponed UoSAT-C mission. UoSAT-D & E will established by the spacecraft launched NASA, develop further the objectives preceding …

Ultrastructural Characteristics Of The Fetal And Neonatal Rat Urinary Bladder, Samuel M. Cohen, Martin Cano, Takao Sakata, Sonny L. Johansson

Scanning Microscopy

The embryologic and neonatal development of the normal rat urinary bladder was investigated in Sprague-Dawley rats by light, transmission, and scanning electron microscopy from day 11 of gestation through 21 days of age. The epithelium at day 11 of gestation is composed of small, loosely-connected, rounded cells with occasional short microvilli on their surfaces. The large polygonal cells characteristic of the adult bladder begin to appear by day 15, but the microridges are not apparent until day 17. By day 20, the epithelium appears morphologically similar to the adult bladder. Several morphological features are observed at different times of gestation …

Optimal Conjunctive Use-Sustained Yield Pumping Analysis For Eastern Arkansas, Rosalinda R.A. Cantiller, Richard C. Peralta, Hossein Azarmnia

Civil and Environmental Engineering Faculty Publications

The likelihood that irrigated agricultural acreages will increase in eastern Arkansas is high. This results from favorable agricultural soils, climate, and the availability of significant water resources.

Effect Of X-Irradiation On Adenylate Cyclase Activity And Cyclic Amp Content Of Primary Human Fibroblasts, Z. Somosy, A. Takáts, Tamara Kubasova, F. Sudár, G. J. Köteles

Scanning Microscopy

Ionizing radiation provokes an increase of the cAMP level in several organs and body fluids. After reviewing the relevant literature we present the results of our own experiments on primary human fibroblasts. X-irradiation at doses of 0.5 and 2.5 Gy in vitro evoked a rapid and reversible increase of adenylate cyclase enzyme activity. A significant increase in cAMP level of these cells was also observed.

Adenylate cyclase was usually localized basolaterally on the surface of unirradiated cells, while irradiation resulted in a modification of distribution, i.e., the enzyme activity also appeared in apical localization.

Measurement And Simulation Of One-Dimensional Transient Three Phase Flow For Monotonic Liquid Drainage, R. J. Lenhard, J. Dane, J. C. Parker, Jagath J. Kaluarachchi

Civil and Environmental Engineering Faculty Publications

Simultaneous movement of oil, water, and air in a sandy porous medium was investigated experimentally under transient flow conditions and results were compared to numerical simulations employing a finite element multiphase flow code. The liquid hydrocarbon was Soltrol 170, a low-density branched alkane mixture. Liquid saturations were measured using a collinear dual-energy gamma radiation apparatus and liquid pressures were measured using hydrophilic (untreated) and hydrophobic (treated) ceramic tensiometers connected to pressure transducers. The experimental regime was selected to impose monotonically draining water and total liquid saturation paths to avoid hysteretic effects. Measured saturations and pressures are compared to values obtained …

The Role Of Scanning Electron Microscopy In Ophthalmic Science, P. Versura, M. C. Maltarello

Scanning Microscopy

The eyeglobe is one of the classical domains of Scanning Electron Microscopy (SEM) in biology as it exposes several inner and outer surfaces. Both corneal and conjunctival epithelia towards the tear film as well as the corneal endothelial cells facing the anterior chamber may be accurately evaluated. The architecture of the angle and particularly the morphology of the Schlemm's canal inner wall are clarified by SEM more than by TEM serial reconstruction. The surfaces of the iris and ciliary body, the zonula and the choroidal vessel arrangement are described in great detail. Three distinct types of membrane anchoring devices are …

Characterization Of Wolbachia Postica Which Causes Hybrid Incompatibility In Alfalfa Weevil, Sy-Jye Christine Leu

Biology

The rickettsia Wolbachia postica is the cause of hybrid incompatibility between males of the western alfalfa weevil and females of eastern or Egyptian weevils. Studies were carried out to obtain information about the biochemical and immunological characteristics of this microorganism. Because of the similarity between rickettsia and mycoplasma under the electron microscope, hybridization of DNA from this microorganism with a mycoplasma-specific gene probe confirmed a previous observation that this microorganism is a rickettsia. A rapid and accurate diagnostic assay for the infection of alfalfa weevils by wolbachia has been accomplished by the production of a polyclonal antibody against Wolbachia postica …

Effects Of Macrocyclic Trichothecene Mycotoxins On The Murine Immune System, Brian J. Hughes

Biology

The macrocyclic trichothecenes are a unique group of toxins which have some antileukemic properties. In the first study, verrucarin A and roridin A were examined. Both mycotoxins were administered intraperitoneally at an equitoxic dose of 0.35 mg/kg to CD-1 mice. Lymphocyte proliferation was studied on days 2, 4, and 7 after animals were dosed with verrucarin A. After day 2, no differences in ³HThymidine (³H-TdR) incorporation were observed using concanavalin A (Con A), phytohaemagglutinin (PHA), pokeweed mitogen (PWM), or lipopolysaccharide (LPS). On day 4, DNA synthesis induced by Con A, PHA, and PWM increased significantly. On day …

Biochemical Purification Of Nuclear Antigens And A Possible Autoimmune Reaction Against These Antigens In Autism, Mohamed Maroof Middib

Biology

Autism is a severe behaviorally defined disorder with a cause (or causes) that is still unknown. The objective of this study was to explore the possibility that autoreactivity against nuclear antigens is associated with this severe developmental disorder. Sera of autistic patients were tested for the presence of antibodies which were reactive with one or more of eight nuclear antigens including double-stranded deoxyribonucleic acid (DS-DNA), single-stranded deoxyribonucleic acid (SS-DNA), histone, deoxyribonucleoprotein (DNP), ribonucleoproteins Ro/SS-A and La/SS-B, RNP, and Smith's antigen (SM). Sera of autistic patients were found to be reactive with four of the nuclear antigens. These antigens included RNP, …

Gene Amplification And Cobalt Resistance In The Eukaryote Dictyostelium Discoideum, Hassan Ashktorab

Biology

The cob-354 cobalt resistance trait of the cellular slime mold Dictyostelium discoideum was shown to be associated with a DNA amplification. The amplified DNA was present in all cob-354 strains and absent from all cobalt sensitive strains. Cured strains, derived by passage of cob-354 strains in the absence of cobaltions, lost both the amplification and the cobalt resistance. The copy number of the amplified DNA was determined to be about 50 in cobalt resistant strain HU1628 by both Southern blot and slot blot analyses. Using transverse alternating field electrophoresis and a cloned portion of the amplification as probe, a band …

Inter-Rater Reliability: A Question Of Measurement In Social Science Research, Lani Kai Eggertsen Goff

Undergraduate Honors Capstone Projects

Erik Erikson (1968) set forth the framework for the conceptualization and adolescent identity formation in the late 1960's. The assessment of identity invokes a subjective measurement of a youth's process and current standing regarding sociopsychological development. According to Adams (1987) throughout Erikson's writings a "conscious sense of individual identity," a process of "ego synthesis" and formation of sense of social "ideals and social identity" are central considerations when discussing identity.

Innovative Government, Laura Elizabeth Huggins

Undergraduate Honors Capstone Projects

American citizens are often dissatisfied with government. They are upset over crumbling city streets, unmowed county lawns, trash on the side of state highways and neglected canyons and parks. In general, they are discontented with the amount of taxes they pay compared to the benefits they see.

Quaternary Geology And Tectonic Geomorphology Of The Pocatello Valley Area, Idaho-Utah, John D. Garr

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Pocatello Valley in southeastern Idaho and northern Utah is a structural and topographic basin bounded on all sides by mountains composed of Paleozoic platform carbonates and elastics. In the late Pleistocene it contained pluvial Lake Utaho, which, prior to 1981, was considered to have been an arm of Lake Bonneville. This study corroborates the finding of Currey (1981) that the two lakes were separate.

The Quaternary deposits examined in this study are divided into two broad groups: those that were deposited prior to the last pluvial lake cycle, and those that were deposited during and after the pluvial lake maximum, …