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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 181 records · Page 10
All sourcesNASA NTRSDOE OSTI
NASA NTRS1990

Photovoltaic superiority for Space Station Freedom power in the 21st century

Complete power systems capable of delivering 75 kW of continuous power in low earth orbit have been compared. Performance, liabilities, and advantages are discussed for a shielded nuclear system, a solar dynamic system, and photovoltaic systems, both current Freedom Si design and near-term GaAs/Ge with NaS storage. System components include power generation, storage (if required), heat rejection, power conversion and distribution, structural support, and shielding (if required). Performance parameters indicate the substantial advantage of the GaAs/Ge photovoltaic system, which does not require altering the support structure of the current Freedom design.

Bailey, Sheila G.↗
NASA NTRS1991

Real-time earthquake monitoring: Early warning and rapid response

A panel was established to investigate the subject of real-time earthquake monitoring (RTEM) and suggest recommendations on the feasibility of using a real-time earthquake warning system to mitigate earthquake damage in regions of the United States. The findings of the investigation and the related recommendations are described in this report. A brief review of existing real-time seismic systems is presented with particular emphasis given to the current California seismic networks. Specific applications of a real-time monitoring system are discussed along with issues related to system deployment and technical feasibility. In addition, several non-technical considerations are addressed including cost-benefit analysis, public perceptions, safety, and liability.

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NASA NTRS1991

An analysis of Space Shuttle countdown activities: Preliminaries to a computational model of the NASA Test Director

Before all systems are go just prior to the launch of a space shuttle, thousands of operations and tests have been performed to ensure that all shuttle and support subsystems are operational and ready for launch. These steps, which range from activating the orbiter's flight computers to removing the launch pad from the itinerary of the NASA tour buses, are carried out by launch team members at various locations and with highly specialized fields of expertise. The liability for coordinating these diverse activities rests with the NASA Test Director (NTD) at NASA-Kennedy. The behavior is being studied of the NTD with the goal of building a detailed computational model of that behavior; the results of that analysis to date are given. The NTD's performance is described in detail, as a team member who must coordinate a complex task through efficient audio communication, as well as an individual taking notes and consulting manuals. A model of the routine cognitive skill used by the NTD to follow the launch countdown procedure manual was implemented using the Soar cognitive architecture. Several examples are given of how such a model could aid in evaluating proposed computer support systems.

John, Bonnie E.↗
NASA NTRS1992

Shuttle Rocket Motor Program: NASA should delay awarding some construction contracts. Report to the Chair, Subcommittee on Government Activities and Transportation, Committee on Government Operations, House of Representatives

Even though the executive branch has proposed terminating the Advanced Solid Rocket Motor (ASRM) program, NASA is proceeding with all construction activity planned for FY 1992 to avoid schedule slippage if the program is reinstated by Congress. However, NASA could delay some construction activities for at least a few months without affecting the current launch data schedule. For example, NASA could delay Yellow Creek's motor storage and dock projects, Stennis' dock project, and Kennedy's rotation processing and surge facility and dock projects. Starting all construction activities as originally planned could result in unnecessarily incurring additional costs and termination liability if the funding for FY 1993 is not provided. If Congress decides to continue the program, construction could still be completed in time to avoid schedule slippage.

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NASA NTRS1930

Contribution to the theory of propeller vibrations

This report presents a calculation of the torsional frequencies of revolving bars with allowance for the air forces. Calculation of the flexural or bonding frequencies of revolving straight or tapered bars in terms of the angular velocity of revolution. Calculation on the basis of Rayleigh's principle of variation. There is also a discussion of error estimation and the accuracy of results. The author then provides an application of the theory to screw propellers for airplanes and the discusses the liability of propellers to damage through vibrations due to lack of uniform loading.

Liebers, F↗
NASA NTRS1994

Regenerating using aqueous cleaners with ozone and electrolysis

A new process converts organic oil and grease contaminates in used water based cleaners into synthetic surfactants. This permits the continued use of a cleaning solution long after it would have been dumped using previously known methods. Since the organic soils are converted from contaminates to cleaning compounds the need for frequent bath dumps is totally eliminated. When cleaning solutions used in aqueous cleaning systems are exhausted and ready for disposal, they will always contain the contaminates removed from the cleaned parts and drag-in from prior cleaning steps. Even when the cleaner is biodegradable these contaminants will frequently cause the waste cleaning solution to be a hazardous waste. Chlorinated solvents are rapidly being replaced by aqueous cleaners to avoid the new ozone-depletion product-labeling-law. Many industry standard halocarbon based solvents are being completely phased out of production, and their prices have nearly tripled. Waste disposal costs and cradle-to-grave liability are also major concerns for industry today. This new process reduces the amount of water and chemicals needed to maintain the cleaning process. The cost of waste disposal is eliminated because the water and cleaning compounds are reused. Energy savings result by eliminating the need for energy currently used to produce and deliver fresh water and chemicals as well as the energy used to treat and destroy the waste from the existing cleaning processes. This process also allows the cleaning bath to be maintained at the peak performance of a new bath resulting in decreased cycle times and decreased energy consumption needed to clean the parts. This results in a more efficient and cost effective cleaning process.

Mcginness, Michael P.↗
NASA NTRS1993

Applying formal methods and object-oriented analysis to existing flight software

Correctness is paramount for safety-critical software control systems. Critical software failures in medical radiation treatment, communications, and defense are familiar to the public. The significant quantity of software malfunctions regularly reported to the software engineering community, the laws concerning liability, and a recent NRC Aeronautics and Space Engineering Board report additionally motivate the use of error-reducing and defect detection software development techniques. The benefits of formal methods in requirements driven software development ('forward engineering') is well documented. One advantage of rigorously engineering software is that formal notations are precise, verifiable, and facilitate automated processing. This paper describes the application of formal methods to reverse engineering, where formal specifications are developed for a portion of the shuttle on-orbit digital autopilot (DAP). Three objectives of the project were to: demonstrate the use of formal methods on a shuttle application, facilitate the incorporation and validation of new requirements for the system, and verify the safety-critical properties to be exhibited by the software.

Cheng, Betty H. C.↗
NASA NTRS1995

The use of ion mobility spectrometry and gas chromatography/mass spectrometry for the detection of illicit drugs on clandestine records

Illicit drug distribution has over the past decade grown tremendously from simple 'drug pushing' where drugs were distributed from poorly organized individuals to today's well organized and well financed drug cartels. This change to a more 'corporate-like' atmosphere has resulted in a greater use of record keeping to monitor the profits generated. The use of record keeping by drug distributors is not restricted to high level drug smugglers but is used at all levels within the distribution network. Dealers at all levels including street dealers are generally 'fronted', given on consignment quantities of drugs that they in turn sell to customers, thereby requiring the need for records to keep track of drug sales versus liabilities. These records because of their illicit nature are often encrypted to hide the fact that they are indeed records of drug transactions. The creation of a handwritten notation concerning a drug transaction is normally brought on because of a purchase or sale. In a sale, this is commonly accomplished through a consignment, or the designation of a quantity to a customer to whom that amount has been 'fronted'. Because this activity generates a debt, it follows that an accounting for payments made, as well as new transactions completed, is only logical. One of the most common means of representing these is through an 'accounting flow', in which payments are subtracted from a running balance while new sales are added to it. The examination of illicit drug records has been the key to the prosecution of numerous federal, state, and local drug cases for a number of years. The Document Section of the FBI Laboratory, through its Racketeering Records Analysis Unit (RRAU), has been involved in such analytical efforts since 1983. Detailed analytical research brought about an evolution in the systematic approach utilized in the RRAU since that time. The close proximity of the drugs to the records often results in trace drug evidence being transferred to the records. The detection of trace drug residue on surfaces by ion mobility spectrometry (IMS) is well documented in literature. The following procedure will deal primarily with the newer techniques of trace drug analysis and drug record analysis developed by the Chemistry/Toxicology Unit of the FBI Laboratory since the more traditional techniques of latent finger print analysis and document analysis are well known.

Donnelly, Brian↗
NASA NTRS1993

Managing systems faults on the commercial flight deck: Analysis of pilots' organization and prioritization of fault management information

In rare instances, flight crews of commercial aircraft must manage complex systems faults in addition to all their normal flight tasks. Pilot errors in fault management have been attributed, at least in part, to an incomplete or inaccurate awareness of the fault situation. The current study is part of a program aimed at assuring that the types of information potentially available from an intelligent fault management aiding concept developed at NASA Langley called 'Faultfinde' (see Abbott, Schutte, Palmer, and Ricks, 1987) are an asset rather than a liability: additional information should improve pilot performance and aircraft safety, but it should not confuse, distract, overload, mislead, or generally exacerbate already difficult circumstances.

Rogers, William H.↗
NASA NTRS1996

The search for materials to mitigate spacecraft charging

As spacecraft orbit the earth, they encounter a variety of particles and radiation. Charged particles are common enough that a spacecraft can collect substantial charges on its surfaces. If these charges are not bled off, they can accumulate until electrostatic discharges occur between a charged surface and some lower-potential location on the craft. Electrostatic discharge (ESD) is the suspected culprit in a number of spacecraft failures. Silverized Teflon film has become the standard heat-reflecting outer layer of spacecraft because of its flexibility, chemical inertness, and low volatiles content. However, as spacecraft are designed to operate in orbits with greater probability of accumulating enough ions and electrons to create ESD, the Teflon-based thermal control blankets are becoming a liability. Unless stringent (and sometimes burdensome) shielding measures are taken, ESD can upset delicate electronic systems by upsetting or destroying components, interfering with radio signals, garbling internal instructions, and so on. As orbits become higher and more eccentric, as electronics become more sensitive, and as fault-free operation becomes more crucial, it is becoming necessary to find a replacement for silver/Teflon that has comparable strength, flexibility and chemical inertness, as well as a much lower potential for ESD. This is a report of the steps taken toward the goal of selecting a replacement for silver/Teflon during the Summer of 1995. It is a condensation of a much larger report available on request from the author. Three tasks were undertaken. Task 1 was to specify desirable properties for thermal control blankets. The second task was to collect data on materials properties from the literature and organize into a format useful for identifying candidate materials. The third task was to identify candidate materials and begin testing.

Losure, Nancy S.↗
NASA NTRS1999

Employee Assistance Program Issues

Employee Assistance Program (EAP) officers, as well as personnel in other disciplines from eight NASA Centers, attended this breakout session. Ms. Brenda Blair, MA, CEAP, a guest speaker at the conference, also attended as a consultant. Representatives from the NASA Centers introduced themselves and spoke briefly about their programs. In a discussion related to the conference theme on benchmarking, quality control issues within the EAP community and adequate documentation of cases were addressed. Disposition and provision for quality assurance checks for EAP providers in single person offices were also discussed. Ms. Blair presented methods for consulting with other NASA personnel in single person EAP offices as a quality control measure. EAP intervention in critical incidents was discussed. The question of whether EAP assistance is an asset or a potential liability in those situations was addressed. Suggestions were made of topics for future EAP video-teleconference topics. A program on EAP ethics was planned for a September video teleconference. Each person was asked to provide intake forms they use to Mr. Gettleman or Ms. Blair. Ms. Blair said she would review the forms to ensure that adequate notification is provided to the client for confidentiality. She would also review them to ensure they have adequate limits of confidentiality--a topic for future video teleconferencing. Mr. Gettleman described the NASA initiative to reduce stresses in the workplace, and the activities of an ad-hoc EAP group that will make recommendations to NASA senior management. Alternative training methods were discussed for reaching target audiences such as employees at risk, supervisors, and others. Pfc. David A. Pendleton, Victim Assistance Coordinator, U.S. Capitol Police. U.S. House of Representatives made a special presentation. Pfc. Pendleton was on duty during the tragic shooting of two Federal guards at the U.S. Capitol. He related the events immediately after the incident. He described the nature and structure of the EAP's and the separate nature of the House and Senate programs. This episode was a particularly difficult situation as large numbers of tourists were involved. William S. Barry, MD, the new Manager of the NASA Occupational Health Program Office was introduced to those attending the breakout session.

Gettleman, Alan G.↗
NASA NTRS1999

The Wallops Flight Facility Model for an Integrated Federal/Commercial Launch Range

Historically, the federal government has been the predominant purchaser of space launches in the United States. The government met its needs through purchase of hardware and services. It also provided the infrastructure necessary to conduct launch operations through federal launch ranges, both military and NASA. Under this model, the government had the complete ownership, responsibility, liability, and expense for launch activities. As the commercial space sector grew, there emerged a corresponding growth in demand for launch range services. However, the expense and complexity of activities has thus far deterred a rapid rise in the establishment of purely commercial launch sites. In this context, purely commercial is defined as "without benefit of capabilities provided by the federal government." Consistent with the Commercial Space Launch Act, in recent years NASA and the Air Force have supported commercial launches from government launch ranges on a cost-reimbursable, non-interference basis. In this mode the commercial launch service providers contract with the government to provide services including use of facilities, tracking and data services, and range safety. As the commercial market projections began to show significant opportunities for economic development, several states established spaceports to provide the services necessary to meet these projected commercial needs. In 1997, NASA agreed to the establishment of the Virginia Space Flight Center (VSFC) at the Wallops Flight Facility. Under this arrangement, NASA agreed to allow Virginia Commercial Space Flight Authority (VCSFA) to construct facilities on NASA property and agreed to provide services in accordance with the Space Act of 1958 and the Commercial Space Launch Act of 1984 (as amended) to support VSFC launch customers. The relationship between NASA and VCSFA, however, has evolved beyond a customer supplier relationship. A partnership relationship has emerged which pairs the strengths of the established NASA test range and the state-sponsored, commercial launch facility provider, in an attempt to satisfy the needs for flexible, low-cost access to space. Furthermore, the future of the NASA/Wallops Test Range is closely linked with the success of VCSFA in promoting commercial launches from Wallops. This paper will describe the changing paradigm of the federal launch range and the unique aspects of the NASA/Wallops Facility relationship with VCSFA. Discussion will include institutional cost-sharing, business development and marketing, joint educational programs, and strategic planning.

Underwood, Bruce E.↗
NASA NTRS2001

An Overview of In-Stu Treatability Studies at Marshall Space Flight Center, Huntsville, Alabama

Marshall Space Flight Center (MSFC) is located in Huntsville, Alabama (north-central Alabama), on approximately 1,840 acres near the center of the U.S. Army's Redstone Arsenal (RSA). MSFC is the National Aeronautics and Space Administration's (NASA's) principal propulsion development center. Its scientists, engineers, and support personnel play a major role in the National Space Transportation System by managing space shuttle mission activities, including the microgravity laboratory. In addition, MSFC will be a significant contributor to several of NASA's future programs, including the Reusable Launch Vehicle (X-33), International Space Station, and Advanced X-ray Astrophysics Facility, as well as research on a variety of space science applications. MSFC has been used to develop, test and manufacture space vehicles and components since 1960, when civilian rocketry and missile activities were transferred from RSA to MSFC. In 1994, MSFC was placed on the National Priority List for the management of hazardous waste sites, under the requirements of the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA). One requirement of the CERCLA program is to evaluate the nature and extent of environmental contamination resulting from identified CERCLA sites, assess the public health and environmental risks associated with the identified contamination, and identify potential remedial actions. A CERCLA remedial investigation (RI) for the groundwater system has identified at least five major plumes of chlorinated volatile organic compounds (CVOCs) in the groundwater beneath the facility. These plumes are believed to be the result of former management practices at 14 main facility locations (termed "source areas") where CVOCs were released to the subsurface. Trichloroethene (TCE) is the predominant CVOC and is common to all the plumes. Perchloroethene (PCE) also exists in two of the plumes. In addition to TCE and PCE, carbon tetrachloride and 1,1,2,2-tetrachloroethane are contained in one of the plumes. The CVOCs are believed to exist as dense non-aqueous phase liquids (DNAPLs) beneath many of the source areas.

McElroy, Bill↗
NASA NTRS2001

Impacts of Interannual Climate Variability on Agricultural and Marine Ecosystems

The El Nino - Southern Oscillation (ENSO) is the dominant mode of global interannual climate variability, and seems to be the only mode for which current prediction methods are more skillful than climatology or persistence. The Zebiak and Cane intermediate coupled ocean-atmosphere model has been in use for ENSO prediction for more than a decade, with notable success. However, the sole dependence of its original initialization scheme and the improved initialization on wind fields derived from merchant ship observations proved to be a liability during 1997/1998 El Nino event: the deficiencies of wind observations prevented the oceanic component of the model from reaching the realistic state during the year prior to the event, and the forecast failed. Our work on the project was concentrated on the use of satellite data for improving various stages of ENSO prediction technology: model initialization, bias correction, and data assimilation. Close collaboration with other teams of the IDS project was maintained throughout.

Cane, M. A.↗
NASA NTRS2001

NASA Alternate Access to Station Service Concept

The evolving nature of the NASA space enterprise compels the agency to develop new and innovative space systems concepts. NASA, working with increasingly strained budgets and a declining manpower base, is attempting to transform from operational activities to procurement of commercial services. NASA's current generation reusable launch vehicle, the Shuttle, is in transition from a government owned and operated entity to a commercial venture to reduce the civil servant necessities for that program. NASA foresees its second generation launch vehicles being designed and operated by industry for commercial and government services. The "service" concept is a pioneering effort by NASA. The purpose the "service" is not only to reduce the civil servant overhead but will free up government resources for further research - and enable industry to develop a space business case so that industry can sustain itself beyond government programs. In addition, NASA desires a decreased responsibility thereby decreasing liability. The Second Generation Reusable Launch Vehicle (RLV) program is implementing NASA's Space Launch Initiative (SLI) to enable industry to develop the launch vehicles of the future. The Alternate Access to Station (AAS) project office within this program is chartered with enabling industry to demonstrate an alternate access capability for the International Space Station (ISS). The project will not accomplish this by traditional government procurement methods, not by integrating the space system within the project office, or by providing the only source of business for the new capability. The project funds will ultimately be used to purchase a service to take re-supply cargo to the ISS, much the same as any business might purchase a service from FedEx to deliver a package to its customer. In the near term, the project will fund risk mitigation efforts for enabling technologies. AAS is in some ways a precursor to the 2nd Generation RLV. By accomplishing ISS resupply with existing technologies, not only will a new category of autonomous vehicles deliver cargo, but a commercial business base will be incubated that will improve the likelihood of commercial convergence with the next generation of RLVs. Traditional paradigms in government management and acquisition philosophy are being challenged in order to bring about the objective of the AAS project. The phased procurement approach is proving to be the most questionable aspect to date. This work addresses the fresh approach AAS is adopting in management and procurement through a study of the AAS history, current solutions, key technologies, procurement complications, and an incremental forward plan leading to the purchase of a service to deliver goods to ISS. Included in this work is a discussion of the Commercial Space Act of 1998 and how it affects government purchase of space launch and space vehicle services. Industry should find these topics pertinent to their current state of business.

Bailey, Michelle D.↗
NASA NTRS2001

Design of Critical Components

Critical component design is based on minimizing product failures that results in loss of life. Potential catastrophic failures are reduced to secondary failures where components removed for cause or operating time in the system. Issues of liability and cost of component removal become of paramount importance. Deterministic design with factors of safety and probabilistic design address but lack the essential characteristics for the design of critical components. In deterministic design and fabrication there are heuristic rules and safety factors developed over time for large sets of structural/material components. These factors did not come without cost. Many designs failed and many rules (codes) have standing committees to oversee their proper usage and enforcement. In probabilistic design, not only are failures a given, the failures are calculated; an element of risk is assumed based on empirical failure data for large classes of component operations. Failure of a class of components can be predicted, yet one can not predict when a specific component will fail. The analogy is to the life insurance industry where very careful statistics are book-kept on classes of individuals. For a specific class, life span can be predicted within statistical limits, yet life-span of a specific element of that class can not be predicted.

Hendricks, Robert C.↗
NASA NTRS2002

National Aeronautics and Space Administration Fiscal Year 2001 Accountability Report

The National Aeronautics and Space Administration (NASA) is an independent Agency established to plan and manage the future of the Nation's civil aeronautics and space program. This Accountability Report covers Federal Fiscal Year (FY) 2001 (October 1, 2000, through September 30, 2001), with discussion of some subsequent events. The Report contains an overview addressing the Agency's critical programs and financial performance and includes highlights of performance organized by goals and objectives of the Enterprises and Crosscutting Processes. The Report also summarizes NASA's stewardship over budget and financial resources, including audited financial statements and footnotes. The financial statements reflect an overall position of offices and activities, including assets and liabilities, as well as results of operations, pursuant to requirements of Federal law (31 U.S.C. 3515(b)). The auditor's opinions on NASA's financial statements, reports on internal controls, and compliance with laws and regulations are included in this report.

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NASA NTRS1991

Performance Testing

Systems Technology, Inc., Hawthorne, CA, developed an electronic Critical Tracking Task (CTT) system that analyzes and rates a subject's visual/motor responses for Ames Research Center. Originally applied to measuring the effects of long term confinement in the mid 1960's, the CTT system is now marketed as FACTOR 1000 by Performance Factors, Inc. Alameda, CA, under a licensing agreement with Systems Technology. The system is a non-invasive, self-administered test that takes less than a minute and detects impairment from a broad range of causes, including stress, fatigue, illness, drugs, or alcohol. It is used daily by Old Town Trolley Tours, San Diego, CA, to assess each driver's physical coordination skills prior to the start of each shift. FACTOR 1000 reduces liabilities and costs related to accidents, and costs less than one dollar per day per employee. Performance Factors is now BioFactors, Inc.

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