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2001

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Major Nutrient Distribution In Relation To The Physical Structure Of The Gulf Of Alaska Shelf, Amy Ruehs Childers Aug 2001

Major Nutrient Distribution In Relation To The Physical Structure Of The Gulf Of Alaska Shelf, Amy Ruehs Childers

Oceanography

The northern Gulf of Alaska is a biologically productive downwelling shelf. Nutrient sources supporting such productivity have not been adequately studied. Thirteen primary stations were occupied twelve times throughout 1998 and 1999 in an attempt to clarify nutrient distributions and sources. The shelf waters were warmer, fresher, lower in nitrate, and higher in phytoplankton biomass in the spring of 1998 compared to 1999. Nitrate, silicate, and phosphate were positively correlated with salinity indicating an offshore nutrient source. The largest rates of new production, estimated from nitrate drawdown in the upper layer between March and July/August, were 2.6 mmole nitrate m⁻² …

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Hacking Digital Video Recorders: Potential Copyright Liability For Dvr Hackers And Service Providers, Ashley A. Johnson Aug 2001

Hacking Digital Video Recorders: Potential Copyright Liability For Dvr Hackers And Service Providers, Ashley A. Johnson

Duke Law & Technology Review

To what extent does Sony's time-shifting fair use argument extend to recent innovations that make it easier for hackers use DVR technology to generate copies of protected material? The author assesses the potential liability of DVR manufacturers against the backdrop of traditional fair use doctrines.

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Development Of A Differential Gps Tracking System For Sounding Rocket Payloads, Jay Gregory Helmericks Aug 2001

Development Of A Differential Gps Tracking System For Sounding Rocket Payloads, Jay Gregory Helmericks

Engineering

The purpose of this thesis was to develop a system that could track a sounding rocket payload with a commercial GPS receiver. A GPS receiver was chosen that still outputs raw data when the COCOM limits are exceeded. All the hardware to support the OEM GPS receiver in a reverse differential system was designed and built, including both a ground system and two flight systems to support both on-board storage and telemetry. A software program was developed to archive and compute positions from the raw data. The GPS system has been ground tested and flown on an Orion sounding rocket. …

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Design Of Circularly Polarized, Omnidirectional Microstrip Sounding Rocket Antennas For Telemetry And Gps Applications, Ty Sullins Aug 2001

Design Of Circularly Polarized, Omnidirectional Microstrip Sounding Rocket Antennas For Telemetry And Gps Applications, Ty Sullins

Engineering

The orientation of a sounding rocket with respect to ground stations or GPS satellites is often highly variable and sometimes unpredictable due to its trajectory and spin. Therefore, a sounding rocket antenna should have a radiation pattern that is nearly omnidirectional to ensure sufficient signal strength in any direction, and the antennas should be circularly polarized to minimize polarization loss. Microstrip antennas are well suited to meet these requirements because they are low profile, lightweight, durable, and can be conformed to nonplanar geometries. Additionally, circularly polarization can be achieved using simple geometries and small size. This dissertation presents the theory …

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Making Life And Taking Life: The Psychology Of Assassination In The Mideast, Ibpp Editor Aug 2001

Making Life And Taking Life: The Psychology Of Assassination In The Mideast, Ibpp Editor

International Bulletin of Political Psychology

This article explores the variants of assassination through linguistic analysis of political conflict within and between Israel, the West Bank, the Gaza Strip, and a global context of nation-states and non-state political actors.

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Portrayal Vs. Reality: Images Of African Americans In Magazine Advertisements, Catherine Elizabeth Davis Aug 2001

Portrayal Vs. Reality: Images Of African Americans In Magazine Advertisements, Catherine Elizabeth Davis

Communication

The images of African Americans in magazine advertisements are changing. As these images change, researchers question whether or not African American socioeconomic and familial status are being accurately represented. George Gerbner's cultivation theory suggests that media play a role in shaping people's perceptions of minority groups. Using content analysis, this study compares the portrayal of African American socioeconomic and familial status in magazine advertisements with 1999 United States Census Bureau socioeconomic statistics of African Americans in the United States. This study found that a discrepancy exists between the portrayal and the reality of African American socioeconomic and familial status than …

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Feeding Ecology Of Maturing Sockeye Salmon (Oncorhynchus Nerka) In Nearshore Waters Of The Kodiak Archipelago, Bruce Charles Mcintosh Aug 2001

Feeding Ecology Of Maturing Sockeye Salmon (Oncorhynchus Nerka) In Nearshore Waters Of The Kodiak Archipelago, Bruce Charles Mcintosh

Fisheries

The diet and feeding behavior of maturing sockeye salmon (Oncorhynchus nerka) were investigated during the final marine phase of the spawning migration, prior to reentering natal streams. The stomach contents of commercially caught sockeye salmon, migrating within the nearshore waters of the Kodiak Archipelago during 1998 and 1999, were examined to determine the level of feeding activity and taxa of dominant prey items. Samples were collected throughout the majority of the migration (early June to late August) from areas known to be used principally as migration corridors, and from areas proximate to several natal streams. Dominant prey of sockeye salmon …

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An Age Structured Model For Assessment And Management Of Copper River Chinook Salmon, James W. Savereide Aug 2001

An Age Structured Model For Assessment And Management Of Copper River Chinook Salmon, James W. Savereide

Fisheries

Chinook salmon in Alaska support human uses through a variety of fisheries. Age-structured assessment models are rarely used for estimating the abundance of exploited stocks. This thesis develops a model for the Copper River chinook salmon population to show its advantages over typical assessment models. Information consists of catch-age data from three fisheries (commercial, recreational, subsistence), and two sources of auxiliary data (escapement index, spawner-recruit relationship). Four approaches utilizing different information sources are explored. Results suggest that an approach utilizing pooled catch-age data with time-varying brood-year proportions produces the best estimates, although retrospective and sensitivity analyses suggest that all four …

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Aerobraking To Lower Apogee In Earth Orbit With The Small Payload Orbit Transfer (Sport™) Microsatellite Vehicle , Paul Gloyer, Tony Robinson, Adeena Mignogna, Yasser Ahmad Aug 2001

Aerobraking To Lower Apogee In Earth Orbit With The Small Payload Orbit Transfer (Sport™) Microsatellite Vehicle , Paul Gloyer, Tony Robinson, Adeena Mignogna, Yasser Ahmad

Small Satellite Conference

AeroAstro, Inc. and Astronautic Technology Sdn. Bhd. (a Malaysian space company) are commercially developing the Small Payload ORbit Transfer (SPORT) vehicle, which uses advanced earth aerobraking technology to achieve efficient orbit transfer from Geosynchronous-Transfer Orbit (GTO) to Low Earth Orbit (LEO). After being delivered to GTO by a large launch vehicle, such as Ariane, SPORT uses its onboard propulsion system to adjust its perigee altitude to about 150 km. At this altitude, the large deployable aerobrake produces enough drag to reduce the apogee altitude from 36,000+ km to about 1,000 km in approximately 300 orbits. Upon reaching the target apogee …

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Development Of A Reusable, Low-Shock Clamp Band Separation System For Small Spacecraft Release Applications , David Dowen, Scott Christiansen, Andrew Peffer Aug 2001

Development Of A Reusable, Low-Shock Clamp Band Separation System For Small Spacecraft Release Applications , David Dowen, Scott Christiansen, Andrew Peffer

Small Satellite Conference

In small spacecraft, the proximity of sensitive components to release systems has led to the need for lowshock spacecraft release systems. Marmon band systems are often desirable for their flight history, structural capability, and reliability. Until recently, only pyrotechnically released clamp bands were readily available. The clamp band system described in ths paper reduces shock in two ways: it eliminates shock typically associated with pyrotechnic release devices as well as utilizing a release device that reduces the shock associated with the rapid release of the preload strain energy. Patented Fast Acting Shockless Separation Nut (FASSN) technology is utilized to convert …

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Specifics Of Small Satellite Propulsion: Part 1, Vadim Zakirov, Martin Sweeting, Peter Erichsen, Timothy Lawrence Aug 2001

Specifics Of Small Satellite Propulsion: Part 1, Vadim Zakirov, Martin Sweeting, Peter Erichsen, Timothy Lawrence

Small Satellite Conference

Small satellite propulsion is a subject of unique constraints and requirements. Based on University of Surrey experience in small satellite building and operation, these features are listed and explained. Available volume is often identified as the most severe constraint for a small satellite with power and cost being the other two major constraints. Mass is often only of secondary importance for small satellites. Propulsion dry mass fraction for a spacecraft grows upon the system scaling-down. For small spacecraft propulsion fraction can easily exceed 85%. In such a case, a combination of independent systems for multifunctional propulsion mission scenarios would aggravate …

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Afrl’S Multi-Satellite Deployment System (Msds), 1lt. Carrie Brackett, Mark Kumashiro, Andrew Peffer Aug 2001

Afrl’S Multi-Satellite Deployment System (Msds), 1lt. Carrie Brackett, Mark Kumashiro, Andrew Peffer

Small Satellite Conference

One new way to perform missions from space is the concept of clusters of microsatellites that operate cooperatively to perform the function of a larger, single satellite. Each smaller satellite communicates with the others and shares the processing, communications, and payload or mission functions. The Air Force Research Laboratory (AFRL) is exploring this new paradigm for performing space missions in a partnership program with AFOSR, DARPA, STP and GSFC, called the University Nanosatellite program. Through this program, AFRL is sponsoring the development and launch of 9 university designed and built nanosatellites. The universities are pursuing creative low-cost space experiments to …

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Suitable Strategies For In-Plane Orbit Acquisition Using Micro-Thrusters, N. Nagarajan, Tan Soon Hie, Teck Boon Lee, Tan Boon Liong Aug 2001

Suitable Strategies For In-Plane Orbit Acquisition Using Micro-Thrusters, N. Nagarajan, Tan Soon Hie, Teck Boon Lee, Tan Boon Liong

Small Satellite Conference

The deviations in the injection orbital parameters, resulting from launcher dispersions, need to be corrected through a set of acquisition maneuvers to achieve the desired nominal parameters. When multiple satellites are injected into a single orbital plane, as a part of constellation establishment, they have to positioned in the plane with appropriate semi-major axis ‘a’ and mean anomaly ‘M’. In this paper, three strategies are studied for achieving orbit acquisition. The first strategy is by deriving an analogy to the Linear Quadratic Regulator (LQR). The state dynamics and the control law are of the form X&= AX + BU and …

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Small Orbit Transfer Vehicle (Otv) For On-Orbit Satellite Servicing And Resupply, John Collins, Hans Meissinger, Robert Bell Aug 2001

Small Orbit Transfer Vehicle (Otv) For On-Orbit Satellite Servicing And Resupply, John Collins, Hans Meissinger, Robert Bell

Small Satellite Conference

The field of on-orbit servicing of space systems has been studied extensively, and techniques for performing satellite resupply and repair functions have been developed in detail. They are covered extensively in the literature. Based on this background, Microcosm has performed design studies, partly under NASA/MSFC contract, of a small-size, 300 kg-class multi-function Orbital Transfer Vehicle (OTV) that can provide servicing and resupply functions for the International Space Station (ISS). It carries the required payload from a launch vehicle upper stage to the Station, and after berthing it supports servicing activities of the ISS crew members. The vehicle has a payload-carrying …

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Cluster Launches Of Small Satellites On Dnepr Launch Vehicle, Vladimir Andreev, Vladimir Mikhailov, Vladislav Solovey, Vladimir Kainov Aug 2001

Cluster Launches Of Small Satellites On Dnepr Launch Vehicle, Vladimir Andreev, Vladimir Mikhailov, Vladislav Solovey, Vladimir Kainov

Small Satellite Conference

September 26, 2000 marked the launch of Dnepr launch vehicle ( converted SS-18 ICBM) with a group of small spacecraft. The rocket was launched from a silo located on Baikonur Cosmodrome. Five spacecraft were injected into a 650 km circular orbit inclined 65 degrees – MegSat-1 and UniSat (Italy), SaudiSat-1A and 1B (Saudi Arabia), and TiungSat-1 (Malaysia). For the purposes of rational use of the SS-18s being eliminated under the START treaty, an International Space Company Kosmotras was established in 1997 by the decision of the governments of Russia and Ukraine, which incorporated rocket and space industry enterprises of both …

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New Launch Methodologies For The Micro-Millennia, Chrishma Hunter Singh-Derewa Aug 2001

New Launch Methodologies For The Micro-Millennia, Chrishma Hunter Singh-Derewa

Small Satellite Conference

Rapid advancements in nano-technology have led to numerous improvements in microsatellite design. In the past twenty years, this class of satellites (10-100 kg mass) has repeatedly demonstrated their worth as vehicles for space science, technology demonstration, communications, remote sensing, education and information transfer. Within the past decade, the dramatic transition from experimentation to significant applications has prompted the implementation of numerous new launch methodologies. However, none have adequately met all the requirements stipulated by the small satellite market. The STARSAT launch vehicle has been tailored to specifically address the needs of the micro-satellite mission at a fraction of the cost …

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Re-Injecting Innovation Into The Space Test Process, Brian Horais, Robert Twiggs Aug 2001

Re-Injecting Innovation Into The Space Test Process, Brian Horais, Robert Twiggs

Small Satellite Conference

The U.S. Space industry is losing market share to the International community, both in the launch vehicle and satellite fabrication marketplaces. Although many argue that this is due to restrictive export controls, this paper presents the concept that the erosion of innovation in the U.S. Space Industry has caused this downturn in U. S. market share. As U.S. space programs have grown in scope and cost, the capacity to accept risk as part of the development process has diminished. As a result, the U.S. Space industry is experiencing erosion in innovation, the foundation of our national security and space commerce …

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Checkup, Lehigh Valley Health Network Aug 2001

Checkup, Lehigh Valley Health Network

Checkup

No abstract provided.

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Summer Mustang, August 16, 2001 Aug 2001

Summer Mustang, August 16, 2001

Cal Poly Student Newspaper

Student newspaper of California Polytechnic State University, San Luis Obispo, CA.

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Bookstore Celebrates Grand Reopening, Lindenwood University Aug 2001

Bookstore Celebrates Grand Reopening, Lindenwood University

Archived Lindenwood Press Releases

No abstract provided.

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Baucus-Rehburg Highway Roundtable Meeting, Max S. Baucus Aug 2001

Baucus-Rehburg Highway Roundtable Meeting, Max S. Baucus

Max S. Baucus Speeches and Remarks

Baucus-Rehburg Highway Roundtable Meeting

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Illinois State University Report, August 16, 2001, Illinois State University Aug 2001

Illinois State University Report, August 16, 2001, Illinois State University

Illinois State University Report (1966-2012)

Illinois State University bi-weekly employee newsletter.

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Wireless Network, Computers, Student-Run Business To Greet Ud Students When They Return To Campus Aug. 22, University Of Dayton Aug 2001

Wireless Network, Computers, Student-Run Business To Greet Ud Students When They Return To Campus Aug. 22, University Of Dayton

News Releases

News release announces that a wireless computer network will be the latest high-tech initiative to greet University of Dayton students when they arrive for the first day of class.

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Crystal Growth, Structure Determination And Magnetism Of A New Hexagonal Rhodate: Ba9rh8o24, Katharine E. Stitzer, M. D. Smith, J. Darriet, Hans Conrad Zur Loye Aug 2001

Crystal Growth, Structure Determination And Magnetism Of A New Hexagonal Rhodate: Ba9rh8o24, Katharine E. Stitzer, M. D. Smith, J. Darriet, Hans Conrad Zur Loye

Faculty Publications

Single crystals of Ba9Rh8O24, grown from a molten potassium carbonate flux, crystallize in the spacegroup R¯3c with lattice parameters of a = 10.0899(4) and c = 41.462(2) Å. Magnetic measurements on oriented single crystals reveal the existence of magnetic anisotropy

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A Study On Thermal Modeling And Heat Load Mitigation For Satellite Electronic Components , Young-Keun Chang, Min-Young Kang, Jin-Han Park, Young-Jin Choi Aug 2001

A Study On Thermal Modeling And Heat Load Mitigation For Satellite Electronic Components , Young-Keun Chang, Min-Young Kang, Jin-Han Park, Young-Jin Choi

Small Satellite Conference

Since most of the satellite components are using various EEE (Electrical, Electronic and Electromechanical) parts, the reliability of EEE parts acts very important in the satellite system. There are many factors that influence the reliability of EEE parts in the satellite system. Excessively dissipated heat can cause the failure of EEE parts and consequently, leading to a failure of total satellite system. In this paper, the thermal modeling using nodal network was compared with that using plate modeling to find out which one is the most suitable methodology. For a comparison, KOMPSAT- 1 SAR was modeled by two different modeling …

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An Rf Plasma Thruster For Use In Small Satellites, Lynn Olson Aug 2001

An Rf Plasma Thruster For Use In Small Satellites, Lynn Olson

Small Satellite Conference

New England Space Works is developing an RF plasma thruster for use in small satellites. The RF plasma thruster is an excellent choice for small satellites because it is compact, low power, and does not require high voltages to operate. Specific impulse can be varied over a range of 1500- 3000 seconds. Electric propulsion is finally entering the spacecraft mainstream. Deep Space 1 was the first spacecraft to use an ion thruster as primary propulsion and electric propulsion is in use for north-south stationkeeping on many communications satellites. Research is active on electric propulsion for small satellites, although limited to …

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Revolutionary Propulsion Concepts For Small Satellites, Steven Wassom Aug 2001

Revolutionary Propulsion Concepts For Small Satellites, Steven Wassom

Small Satellite Conference

This paper addresses the results of a trade study in which four novel propulsion approaches are applied to a 100-kg-class satellite designed for rendezvous, reconnaissance, and other on-orbit operations. The technologies, which are currently at a NASA technology readiness level of 4, are known as solar thermal propulsion, digital solid motor, water-based propulsion, and solid pulse motor. Sizing calculations are carried out using analytical and empirical parameters to determine the propellant and inert masses and volumes. The results are compared to an offthe- shelf hydrazine system using a trade matrix “scorecard.” Other factors considered besides mass and volume include safety, …

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Micro Digital Solar Attitude Detector And Imager, Stephen Jaskulek, Kim Strohbehn, Mark Martin Aug 2001

Micro Digital Solar Attitude Detector And Imager, Stephen Jaskulek, Kim Strohbehn, Mark Martin

Small Satellite Conference

The Johns Hopkins University Applied Physics Laboratory (JHU/APL) has developed the first generation of a micro digital solar attitude detector (DSAD). The micro-DSAD (ìDSAD) design is based on our patented approach of combining a centroiding position-sensitive active-pixel architecture with standard imaging capability for providing optional “engineering channel” images. This approach avoids the need for a DSP (digital signal processor) in computing the position, thus dramatically lowering the required mass and power resources. The ìDSAD technology is presently at Technology Readiness Level (TRL) 5. We have demonstrated robust performance, significant total dose radiation tolerance, and single-event latchup immunity on small format …

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Design And Development Of A Compact Magnetic Bearing Momentum Wheel For Micro And Small Satellites , Michael Scharfe, Thomas Roschke, Enrico Bindl, Daniel Blonski Aug 2001

Design And Development Of A Compact Magnetic Bearing Momentum Wheel For Micro And Small Satellites , Michael Scharfe, Thomas Roschke, Enrico Bindl, Daniel Blonski

Small Satellite Conference

Reaction and momentum wheels have become standard equipment for three-axis attitude stabilisation of conventional satellite classes as used e.g. for telecommunication and remote sensing missions. Owing to very compact mechanical designs and highly integrated electronics, wheels are now also more and more interesting for small satellites up to 100…200 kg with increasingly demanding requirements on attitude control. Wheels suitable for small satellites have a typical momentum capacity up to approximately 0.4 Nms, and masses up to about 2 kg. All existing miniature wheels known to the authors are relying on ball bearings for rotor suspension, which may limit the lifetime …

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Yamsat: The First Picosatellite Being Developed In Taiwan, Albert Lin, Chih-Li Chang, Steven Tsai, Joe Fong, Chan-Peng Chang, Robin Lin, Chin Wen Liu, Marco Yeh, M.H. Chung, Hsu-Pin Pan, Chi-Hung Hwang Aug 2001

Yamsat: The First Picosatellite Being Developed In Taiwan, Albert Lin, Chih-Li Chang, Steven Tsai, Joe Fong, Chan-Peng Chang, Robin Lin, Chin Wen Liu, Marco Yeh, M.H. Chung, Hsu-Pin Pan, Chi-Hung Hwang

Small Satellite Conference

This paper describes the current planning and design of the YamSat, the first picosatellite being developed in Taiwan. The design, analysis, manufacture, integration, test and operation of the YamSat will be performed by the National Space Program Office (NSPO), Taiwan, R.O.C, in cooperation with other domestic organizations and companies. It is a member of the CubeSat [1], 10cm x 10cm x 10cm size and within 1kg mass. The major objective of the YamSat is to qualify in space the components and technology developed in Taiwan, including a micro-spectrometer payload using Micro Electro Mechanical Systems (MEMS) technology. The YamSat will be …

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