Governments and privately-held utilities will have to drastically reduce their carbon emissions to mitigate climate change. Such reductions will require transitioning electrical infrastructure to rely on cleaner fuels and power-generation technologies. Despite the myriad factors influencing both the process and eventual outcome of these transitions, it is typically transitions’ cost and individuals’ willingness to pay (WTP) for them that dominate both strategic planning and political...
Topics: Energy portfolios, Multi-criteria decision analysis, Social and environmental attributes,...
A generalized approach is proposed to support integrated traffic flow management decision making studies at both the U.S. national and regional levels. It can consider tradeoffs between alternative optimization and heuristic based models, strategic versus tactical flight controls, and system versus fleet preferences. Preliminary testing was accomplished by implementing thirteen unique traffic flow management models, which included all of the key components of the system and conducting 85,...
Topics: NASA Technical Reports Server (NTRS), AIR TRAFFIC CONTROL, DECISION MAKING, AIR TRANSPORTATION,...
The six studies which are addressed are entitled: Design Modularity and Commonality; Modification of Existing Hardware (COTS) vs. New Hardware Build Cost Analysis; Automation Cost vs. Crew Utilization; Hardware Miniaturization versus Cost; Space Station Freedom/Spacelab Modules Compatibility vs. Cost; and Prototype Utilization in the Development of Space Hardware. The product of these six studies was intended to provide a knowledge base and methodology that enables equipment produced for the...
Topics: NASA Technical Reports Server (NTRS), COST ANALYSIS, EXOBIOLOGY, FUNCTIONAL DESIGN SPECIFICATIONS,...
Papers presented at the NASA Symposium on Recent Experiences in Multidisciplinary Analysis and Optimization held at NASA Langley Research Center, Hampton, Virginia April 24 to 26, 1984 are given. The purposes of the symposium were to exchange information about the status of the application of optimization and associated analyses in industry or research laboratories to real life problems and to examine the directions of future developments. Information exchange has encompassed the following: (1)...
Topics: NASA Technical Reports Server (NTRS), AIRCRAFT DESIGN, COMPUTER AIDED DESIGN, CONFERENCES, DESIGN...
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47
Jul 14, 2016
07/16
by
MyMCM
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In this MyMCMedia Extra Video, Montgomery County Executive Isiah Leggett reminds residents at a recent budget forum about how much the county has going for it right now.
Topics: Maryland, Montgomery County, Montgomery County Media, MyMCM, Public Access TV, Community Media,...
There is increased awareness of anthropogenic factors affecting climate change and urgency to slow the negative impact. Greenhouse gases, oxides of Nitrogen and contrails resulting from aviation affect the climate in different and uncertain ways. This paper develops a flexible simulation and optimization software architecture to study the trade-offs involved in reducing emissions. The software environment is used to conduct analysis of two approaches for avoiding contrails using the concepts of...
Topics: NASA Technical Reports Server (NTRS), MAN ENVIRONMENT INTERACTIONS, CLIMATE CHANGE, CONTRAILS,...
The study of an Advanced Technology Space Station which would utilize the capabilities of subsystems projected for the time frame of the years 2000 to 2025 is discussed. The study includes tradeoffs of nuclear versus solar dynamic power systems that produce power outputs of 2.5 megawatts and analyses of the dynamics of the spacecraft of which portions are rotated for artificial gravity. The design considerations for the support of a manned Mars mission from low Earth orbit are addressed. The...
Topics: NASA Technical Reports Server (NTRS), ARTIFICIAL GRAVITY, DESIGN ANALYSIS, ROTATION, SPACE...
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210
May 31, 2011
05/11
by
Vinals, Jorg
texts
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The research summarized in this report has involved a combined theoretical and computational study of fluid flow that results from the random acceleration environment present onboard space orbiters, also known as g-jitter. We have focused on a statistical description of the observed g-jitter, on the flows that such an acceleration field can induce in a number of experimental configurations of interest, and on extending previously developed methodology to boundary layer flows. Narrow band noise...
Topics: ALUMINUM NITRIDES, HIGH TEMPERATURE, FIELD EFFECT TRANSISTORS, METAL OXIDE SEMICONDUCTORS,...
The computer program CASCOMP, which may be used in comparative design studies of lighter than air vehicles by rapidly providing airship size and mission performance data, was prepared and documented. The program can be used to define design requirements such as weight breakdown, required propulsive power, and physical dimensions of airships which are designed to meet specified mission requirements. The program is also useful in sensitivity studies involving both design trade-offs and...
Topics: NASA Technical Reports Server (NTRS), AIRSHIPS, COMPUTER PROGRAMS, PERFORMANCE, SIZING (SHAPING),...
The effects of slowly varying and persisting covariate effects on the accuracy and precision of experimental result is reviewed, as is the rationale for run-order randomization as a quality assurance tactic employed in the Modern Design of Experiments (MDOE) to defend against such effects. Considerable analytical complexity is introduced by restrictions on randomization in configuration aerodynamics tests because they involve hard-to-change configuration variables that cannot be randomized...
Topics: NASA Technical Reports Server (NTRS), AERODYNAMIC CONFIGURATIONS, AERODYNAMICS, EXPERIMENT DESIGN,...
A hardware simulation which emulates an automatically acquiring transmit receive spread spectrum communication and tracking system and developed for use in future NASA programs involving digital communications is considered. The system architecture and tradeoff analysis that led to the selection of the system to be simulated is presented.
Topics: NASA Technical Reports Server (NTRS), BIT SYNCHRONIZATION, COMPUTERIZED SIMULATION, PULSE...
Real-time AI systems have begun to address the challenge of restructuring problem solving to meet real-time constraints by making key trade-offs that pursue less than optimal strategies with minimal impact on system goals. Several approaches for adapting to dynamic changes in system operating conditions are known. However, simultaneously adapting system decision criteria in a principled way has been difficult. Towards this end, a general technique for dynamically making such trade-offs using a...
Topics: NASA Technical Reports Server (NTRS), ARTIFICIAL INTELLIGENCE, DATA MANAGEMENT, DECISION THEORY,...
386
386
Sep 20, 2010
09/10
by
Cane, H. V.; Richardson, I. G.; Vonrosenvinge, T. T
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The time histories of particles in the energy range 1 MeV to 1 GeV at times of all greater than 3 percent cosmic ray decreases in the years 1978 to 1982 are studied. Essentially all 59 of the decreases commenced at or before the passages of interplanetary shocks, the majority of which accelerated energetic particles. We use the intensity-time profiles of the energetic particles to separate the cosmic ray decreases into four classes which we subsequently associate with four types of solar wind...
Topics: EXTRATERRESTRIAL RESOURCES, GENERAL OVERVIEWS, HIGH VACUUM, LUNAR SOIL, MICROGRAVITY, MINING,...
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392
Jun 13, 2011
06/11
by
Kremic, TIbor; Tukel, Oy
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There has been a tremendous growth in outsourcing practices in recent years. The public organizations in the United States have outsourced some functions and are now being compelled to outsource additional ones. While there are numerous studies that document and analyze outsourcing practices, there is limited research to guide public or governmental organizations in determining what functions to outsource. This study fills this gap by developing a decision support model for a typical public...
Topics: COMMERCIAL AIRCRAFT, MONTE CARLO METHOD, VARIABILITY, REGULATIONS, PROTOTYPES, POSITION (LOCATION),...
The probe bus and orbiter subsystems are defined, and tradeoffs analyzed. Subsystems discussed include: communications, electric power, data handling, attitude determination and control, propulsion, thermal control, structure and mechanisms, NASA/ESRO orbiter interface, mission operation, and flight support.
Topics: NASA Technical Reports Server (NTRS), SYSTEMS ENGINEERING, TRADEOFFS, VENUS PROBES, ATTITUDE...
The final goal for a delivered system (whether a car, aircraft, avionics box or computer) should be its availability to operate and perform its intended function over its expected design life. Hence, in designing a system, we cannot think in terms of delivering the system and just walking away. The system supplier needs to provide support throughout the operating life of the product. Here, supportability requires an effective combination of reliability, maintainability, logistics and operations...
Topics: NASA Technical Reports Server (NTRS), AVIONICS, LOGISTICS, MAINTAINABILITY, RELIABILITY, SERVICE...
472
472
Jul 12, 2010
07/10
by
Padfield, G. D.; Duval, R. K
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A set of results on rotorcraft system identification is described. Flight measurements collected on an experimental Puma helicopter are reviewed and some notable characteristics highlighted. Following a brief review of previous work in rotorcraft system identification, the results of state estimation and model structure estimation processes applied to the Puma data are presented. The results, which were obtained using NASA developed software, are compared with theoretical predictions of roll,...
Topics: FLIR DETECTORS, FLIGHT SIMULATION, LOW ALTITUDE, NAVIGATION AIDS, PILOT PERFORMANCE, TRADEOFFS,...
Recent advances in low-end processor and network technology have made it possible to build a "supercomputer" out of commodity components. We develop simple models of the NAS Parallel Benchmarks version 2 (NPB 2) to explore the cost/performance trade-offs involved in building a balanced parallel computer supporting a scientific workload. We develop closed form expressions detailing the number and size of messages sent by each benchmark. Coupling these with measured single processor...
Topics: NASA Technical Reports Server (NTRS), PERFORMANCE PREDICTION, PARALLEL COMPUTERS, COSTS, WORKLOADS...
A technology program was conducted to identify and verify the optimum valve and actuation system concept for the Space Shuttle Orbit Maneuvering System engine. Of major importance to the valve and actuation system selection was the ten-year, 100-mission, 10,000-cycle life requirement, while maintaining high reliability, low leakage, and low weight. Valve and actuation system concepts were comparatively evaluated against past valve failure reports and potential failure modes due to the shuttle...
Topics: NASA Technical Reports Server (NTRS), ACTUATORS, CONTROL VALVES, ENGINE CONTROL, FUEL VALVES, SPACE...
The Global Exploration Roadmap (GER) was released by the International Space Exploration Coordination Group (ISECG) in September of 2011. It describes mission scenarios that begin with the International Space Station and utilize it to demonstrate necessary technologies and capabilities prior to deployment of systems into Earth-Moon space. Deployment of these systems is an intermediate step in preparation for more complex deep space missions to near-Earth asteroids and eventually Mars. In one of...
Topics: NASA Technical Reports Server (NTRS), DESIGN ANALYSIS, ORBITAL MECHANICS, SPACE EXPLORATION, SPACE...
The methodology evaluation and recommendation are part of an effort to improve Hardware versus Manpower (HARDMAN) methodology for projecting manpower, personnel, and training (MPT) to support new acquisition. Several different validity tests are employed to evaluate the methodology. The methodology conforms fairly well with both the MPT user needs and other accepted manpower modeling techniques. Audits of three completed HARDMAN applications reveal only a small number of potential problem areas...
Topics: NASA Technical Reports Server (NTRS), EDUCATION, MANPOWER, PERSONNEL DEVELOPMENT, PERSONNEL...
With a temperature higher than the inside of your oven and atmospheric pressure equal to that a kilometer under the ocean, the surface of Venus is one of the most hostile environments in the solar system, and Venus exploration presents a challenge to technology. This lecture presents mission trade-offs and discusses a proposed mission concept for rover and aircraft based exploration of the surface and atmosphere of Venus. Several approaches to the technology, electronics, mechanical parts, and...
Topics: NASA Technical Reports Server (NTRS), VENUS ATMOSPHERE, VENUS SURFACE, ATMOSPHERIC PRESSURE,...
The digital control portion of a low-cost 406-MHz COSPAS/SARSAT emergency beacon has been designed and breadboarded at the NASA Lewis Research Center. This report discusses the requirements and design tradeoffs of the digital controller and describes the hardware and software design, which is available only to United States citizens and companies.
Topics: NASA Technical Reports Server (NTRS), BEACONS, CONTROLLERS, COSPAS, DIGITAL SYSTEMS, EMERGENCY...
The object of the Maintenance and Supply Option was to develop a high level operational philosophy related to maintenance and supply operations and incorporate these concepts into the Lunar Base Study. Specific products to be generated during this task were three trade studies and a conceptual design of the Logistic Supply Module. The crew size study was performed to evaluate crew sizes from the baseline size of four to a crew size of eight and determine the preferred crew size. The second...
Topics: NASA Technical Reports Server (NTRS), EXTRAVEHICULAR ACTIVITY, LIFE SUPPORT SYSTEMS, LUNAR BASES,...
The gas turbine combustion system design and development effort is an engineering exercise to obtain an acceptable solution to the conflicting design trade-offs between combustion efficiency, gaseous emissions, smoke, ignition, restart, lean blowout, burner exit temperature quality, structural durability, and life cycle cost. For many years, these combustor design trade-offs have been carried out with the help of fundamental reasoning and extensive component and bench testing, backed by...
Topics: NASA Technical Reports Server (NTRS), AEROTHERMODYNAMICS, COMBUSTION CHAMBERS, COMBUSTION...
Pulsed CO2 lasers have many applications in aeronautics, space research, weather monitoring and other areas. Full exploitation of the potential of these lasers is hampered by the dissociation of CO2 that occurs during laser operation. The development of closed-cycle CO2 lasers requires active CO-O2 recombination (CO oxidation) catalysts and design methods for implementation of catalysts inside lasers. The performance criteria and constraints involved in the design of catalyst configurations for...
Topics: NASA Technical Reports Server (NTRS), CARBON DIOXIDE, CARBON DIOXIDE LASERS, CATALYSTS, COMPUTER...
The Advanced Rotorcraft Transmission (ART) program is structured to incorporate key emerging material and component technologies into an advanced rotorcraft transmission with the intention of making significant improvements in the state of the art (SOA). Specific objectives of ART are: (1) Reduce transmission weight by 25 pct.; (2) Reduce transmission noise by 10 dB; and (3) Improve transmission life and reliability, while extending Mean Time Between Removal to 5000 hr. Boeing selected a...
Topics: NASA Technical Reports Server (NTRS), BEARINGS, GEARS, HELICOPTER PROPELLER DRIVE, PROPULSIVE...
A discrete, semi-analytical sensitivity analysis procedure has been developed for calculating aerodynamic design sensitivities. The sensitivities of the flow variables and the grid coordinates are numerically calculated using direct differentiation of the respective discretized governing equations. The sensitivity analysis techniques are adapted within a parabolized Navier Stokes equations solver. Aerodynamic design sensitivities for high speed wing-body configurations are calculated using the...
Topics: NASA Technical Reports Server (NTRS), SONIC BOOMS, NOISE REDUCTION, AERODYNAMIC CHARACTERISTICS,...
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314
Jun 2, 2011
06/11
by
Miller, Dean R.; Lynch, Christopher J.; Tate, Peter A
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The Icing Branch and Imaging Technology Center at NASA Glenn Research Center have recently been involved in several projects where high speed close-up imaging was used to investigate water droplet impact/splash, and also ice particle impact/bounce in an icing wind tunnel. The combination of close-up and high speed imaging capabilities were required because the particles being studied were relatively small (d < 1 mm in diameter), and the impact process occurred in a very short time period...
Topics: NUCLEAR ELECTRIC PROPULSION, POWER REACTORS, SPACECRAFT MODULES, OPTIMIZATION, GENETIC ALGORITHMS,...
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392
Nov 9, 2020
11/20
by
Everything-Voluntary.com
audio
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his episode features a talk by economist and Nobel Laureate Milton Friedman from 1993. From the grand opening of the Cato Institutes's headquarters in Washington, D.C. in 1993, Friedman gives a talk about popular political aphorisms, one of his favorites being the one he helped popularize in the title of his 1975 book, "There's no such thing as a free lunch."
Topics: economics, econ101, government, finance, social democracy, welfare state, tradeoffs, taxation,...
Concepts for the 1990's space station envision an initial operational capability with electrical power output requirements of approximately 75 kW and growth power requirements in the range of 300 kW over a period of a few years. Photovoltaic and solar dynamic power generation techniques are contenders for supplying this power to the space station. A study was performed to identify growth power subsystem impacts on other space station subsystems. Subsystem interactions that might suggest early...
Topics: NASA Technical Reports Server (NTRS), GROWTH, SPACE STATIONS, SPACECRAFT POWER SUPPLIES, SYSTEMS...
288
288
Jul 11, 2010
07/10
by
LEBLANC, G
texts
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DISTANCE PREDICTING METHODS FOR AIRCRAFT BRAKING PERFORMANCE IS DISCUSSED FOR THE CASE WHEN BRAKING IS NOT LIMITED BY THE BRAKES, BUT BY THE CHARACTERISTICS OF TIRE-RUNWAY CONTACT. RECENTLY DEVELOPED FIGHTER AND LARGE CAPACITY TRANSPORT AIRCRAFT REQUIRE THAT STOPPING DISTANCES AND RUNWAY LENGTHS BE ACCURATELY CORRELATED FOR DIFFERENT TOUCHDOWN VELOCITIES, WIND, AND RUNWAY CONDITIONS.
Topics: NUCLEAR ELECTRIC PROPULSION, SPACECRAFT CONFIGURATIONS, PAYLOADS, SPACECRAFT DESIGN, TEMPERATURE...
Trade studies plans for a number of elements in the Liquid Rocket Booster (LRB) component of the Space Transportation System (STS) are given in viewgraph form. Some of the elements covered include: avionics/flight control; avionics architecture; thrust vector control studies; engine control electronics; liquid rocket propellants; propellant pressurization systems; recoverable spacecraft; cryogenic tanks; and spacecraft construction materials.
Topics: NASA Technical Reports Server (NTRS), AVIONICS, BOOSTER ROCKET ENGINES, ROCKET ENGINE CONTROL,...
The mission, systems, operations, ground systems, and reliability analysis of the Thor/Delta baseline design used for the Pioneer Space Probe are discussed. Tradeoff decisions concerning spin axis orientation, bus antenna design, communication system design, probe descent, and reduced science payload are analyzed. The reliability analysis is made for the probe bus mission, large probe mission, and small probe mission. Detailed mission sequences were established to identify critical areas and...
Topics: NASA Technical Reports Server (NTRS), MISSION PLANNING, PIONEER SPACE PROBES, SPACE MISSIONS,...
A feasibility analysis and trade-offs for a one-way Doppler extractor using digital VCO techniques is presented. The method of Doppler measurement involves the use of a digital phase lock loop; once this loop is locked to the incoming signal, the precise frequency and hence the Doppler component can be determined directly from the contents of the digital control register. The only serious error source is due to internally generated noise. Techniques are presented for minimizing this error...
Topics: NASA Technical Reports Server (NTRS), DIGITAL TECHNIQUES, DOPPLER EFFECT, EXTRACTION, PHASE LOCKED...
We use numerical simulation to investigate the high-temperature (up to 500K) operation of SOI MOSFETs with Aluminum-Nitride (AIN) buried insulators, rather than the conventional silicon-dioxide (SiO2). Because the thermal conductivity of AIN is about 100 times that of SiO2, AIN SOI should greatly reduce the often severe self-heating problem of conventional SOI, making SOI potentially suitable for high-temperature applications. A detailed electrothermal transport model is used in the...
Topics: NASA Technical Reports Server (NTRS), ALUMINUM NITRIDES, HIGH TEMPERATURE, FIELD EFFECT...
This paper describes the development of an efficient algorithm for computing the product of a matrix and vector on a CYBER 205 vector computer. The desire to provide software which allows the user to choose between the often conflicting goals of minimizing central processing unit (CPU) time or storage requirements has led to a diagonal-based algorithm in which one of four types of storage is selected for each diagonal. The candidate storage types employed were chosen to be efficient on the...
Topics: NASA Technical Reports Server (NTRS), CDC CYBER 205 COMPUTER, COMPUTER STORAGE DEVICES, MATRIX...
One way to implement a fault-tolerant service is by using multiple servers that fail independently. The state of the service is replicated and distributed among these servers, and updates are coordinated so that even when a subset of the servers fail, the service remains available. A common approach to structuring such replicated services is to designate one server as the primary and all the others as backups. Clients make requests by sending messages only to the primary. If the primary fails,...
Topics: NASA Technical Reports Server (NTRS), BLOCKING, FAULT TOLERANCE, MESSAGE PROCESSING, PROTOCOL...
This report defines a hardware architecture approach for software-defined radios to enable commonality among NASA space missions. The architecture accommodates a range of reconfigurable processing technologies including general-purpose processors, digital signal processors, field programmable gate arrays, and application-specific integrated circuits (ASICs) in addition to flexible and tunable radiofrequency front ends to satisfy varying mission requirements. The hardware architecture consists...
Topics: NASA Technical Reports Server (NTRS), RADIO EQUIPMENT, TELECOMMUNICATION, APPLICATION SPECIFIC...
The solar power satellite and associated microwave system was reoptimized with larger antennas (at 2.45 GHz), reduced output powers, and smaller rectennas. Four constraints were considered: (1) the 23 mw/sq cm ionospheric limit; (2) a higher (54 mW/sq cm) ionospheric limit; (3) the 23 KW/sq cm thermal limit in the antenna; and (4) an improved thermal design allowing 33% additional waste heat. The differential costs in electricity for seven antenna/rectenna configurations operating at 2.45 GHz...
Topics: NASA Technical Reports Server (NTRS), RECTENNAS, SIZE (DIMENSIONS), SOLAR POWER SATELLITES,...
399
399
Jun 12, 2011
06/11
by
Clancey, William J.; Semple, Abigail, et al; Sierhaus, Maarten; Alena, Richard L.; Berrios, Daniel; Dowding, John; Graham, Jeffrey S.; Tyree, Kim S.; Hirsh, Robert L.; Garry, W. Brent
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We have developed and tested an advanced EVA communications and computing system to increase astronaut self-reliance and safety, reducing dependence on continuous monitoring and advising from mission control on Earth. This system, called Mobile Agents (MA), is voice controlled and provides information verbally to the astronauts through programs called personal agents. The system partly automates the role of CapCom in Apollo-including monitoring and managing EVA navigation, scheduling, equipment...
Topics: COMMERCIAL AIRCRAFT, TAIWAN, SELECTION, SEATS, PASSENGERS, EXPANSION, CIVIL AVIATION, AIRLINE...
To determine the feasibility of providing efficient RF power transmission from a Mars-stationary orbit to the surface of the planet, an assessment was made focussing on RF propagation in the 2.45- to 300-GHz range. The proposed orbiting system configuration provides for power generation by either photovoltaic array or nuclear reactor, the conversion of the dc output to RF, and subsequent propagation of RF energy from the orbiting array to the Martian surface. On the planet, a rectenna array...
Topics: NASA Technical Reports Server (NTRS), ENERGY CONVERSION, MARS SURFACE, MICROWAVE POWER BEAMING,...
An analysis was made of cost tradeoffs for shaping modified square wafers from cylindrical crystals. Tests were conducted of the effectiveness of texture etching for removal of surface damage on sawed wafers. A single step texturing etch appeared adequate for removal of surface damage on wafers cut with multiple blade reciprocating slurry saws.
Topics: NASA Technical Reports Server (NTRS), COST ANALYSIS, PHOTOVOLTAIC CELLS, SILICON, SOLAR ARRAYS,...
NASA Ames Research Center (ARC) is evaluating options of reuse of its historic Hangar 1. As a part of this evaluation, a qualitative fire risk assessment study was performed to evaluate the potential threat of combustion of the historic hangar. The study focused on the fire risk trade-off of either installing or not installing a Special Hazard Fire Suppression System in the Hangar 1 deck areas. The assessment methodology was useful in discussing the important issues among various groups within...
Topics: NASA Technical Reports Server (NTRS), FIRES, RISK ASSESSMENT, FIRE PREVENTION, HANGARS, COMBUSTION,...
A conceptual design was performed for a 6-U cubesat for a technology demonstration to be launched on the NASA Space Launch System (SLS) test launch EM-1, to be launched into a free-return translunar trajectory. The mission purpose was to demonstrate use of electric propulsion systems on a small satellite platform. The candidate objective chosen was a mission to visit a Near-Earth asteroid. Both asteroid fly-by and asteroid rendezvous missions were analyzed. Propulsion systems analyzed included...
Topics: NASA Technical Reports Server (NTRS), SPACECRAFT LAUNCHING, ASTEROID MISSIONS, TRADEOFFS,...
As space power levels increase to meet mission objectives and also as the transmission distance between power source and load increases, the mass, volume, power loss, and operating voltage and temperature become important system design considerations. This analysis develops the dependence of the specific mass and percent power loss on hte power and voltage levels, transmission distance, operating temperature and conductor material properties. Only radiation cooling is considered since the...
Topics: NASA Technical Reports Server (NTRS), COOLING, DIRECT CURRENT, RADIATIVE HEAT TRANSFER, SPACE...
System level trade-offs carried out during Mobile Satellite (M-SAT) design activities are described. These trade-offs relate to the use of low level beam forming, flexible power and spectrum distribution, and selection of the number of beams to cover the service area. It is shown that antenna performance can be improved by sharing horns between beams using a low level beam forming network (BFN). Additionally, greatly increased power utilization is possible using a hybrid matrix concept to share...
Topics: NASA Technical Reports Server (NTRS), ANTENNA DESIGN, ANTENNA FEEDS, COLLIMATION, MSAT, SATELLITE...
This report describes an analytical and experimental investigation of AeroVironment's Quasi-Bipolar battery concept. The modelling/battery design part of the study demonstrates that there is a trade-off between thermal and specified electrical performance. Even so, quasi-bipolar batteries can be designed, with ten times better thermal uniformity, that meet or exceed current state-of-the-art hybrid-electric vehicle battery pack performance, even using the same active materials. The thermal...
Topics: NASA Technical Reports Server (NTRS), BIPOLARITY, ELECTRIC BATTERIES, FABRICATION, PRODUCT...
A wide range of information transfer demands were identified and analyzed. They were then combined into an appropriate set of requirements for satellite communication services. In this process the demands were ranked and combined into single and multipurpose satellite systems. A detailed analysis was performed on each satellite system to determine: total system cost, including both ground and space segments; sensitivities of the systems to various system tradeoffs; and forcing functions which...
Topics: NASA Technical Reports Server (NTRS), ARTIFICIAL SATELLITES, COMMUNICATING, COST ANALYSIS,...
This paper presents a high-level design for a reliable computing platform for real-time control applications. The design tradeoffs and analyses related to the development of a formally verified reliable computing platform are discussed. The design strategy advocated in this paper requires the use of techniques that can be completely characterized mathematically as opposed to more powerful or more flexible algorithms whose performance properties can only be analyzed by simulation and testing....
Topics: NASA Technical Reports Server (NTRS), RELIABILITY ANALYSIS, ARCHITECTURE (COMPUTERS), ALGORITHMS,...
