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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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NASA NTRS1993

The molecular matching problem

Molecular chemistry contains many difficult optimization problems that have begun to attract the attention of optimizers in the Operations Research community. Problems including protein folding, molecular conformation, molecular similarity, and molecular matching have been addressed. Minimum energy conformations for simple molecular structures such as water clusters, Lennard-Jones microclusters, and short polypeptides have dominated the literature to date. However, a variety of interesting problems exist and we focus here on a molecular structure matching (MSM) problem.

Kincaid, Rex K.↗

NASA NTRS1994

Technical parameters for specifying imagery requirements

Providing visual information acquired from remote events to various operators, researchers, and practitioners has become progressively more important as the application of special skills in alien or hazardous situations increases. To provide an understanding of the technical parameters required to specify imagery, we have identified, defined, and discussed seven salient characteristics of images: spatial resolution, linearity, luminance resolution, spectral discrimination, temporal discrimination, edge definition, and signal-to-noise ratio. We then describe a generalizing imaging system and identified how various parts of the system affect the image data. To emphasize the different applications of imagery, we have constrasted the common television system with the significant parameters of a televisual imaging system for technical applications. Finally, we have established a method by which the required visual information can be specified by describing certain technical parameters which are directly related to the information content of the imagery. This method requires the user to complete a form listing all pertinent data requirements for the imagery.

Coan, Paul P.↗

NASA NTRS1992

Space medicine research: Needs for the 21st century

Space medicine research in the 21st century will continue to focus on the four major areas including: (1) expansion of the current incomplete knowledge base of clinical and subclinical physiological changes due to microgravity; (2) development of countermeasures to extend the capabilities of the human performance envelope in extended duration flights; (3) development of novel methods for delivering all aspects of a comprehensive health care system in extreme remote conditions: and (4) further research and application of systems for biological materials processing. New space transportation vehicles will place unique physiologic and human factors demands on the human system, while providing better access to platforms for materials processing. Success in meeting the demands in each of the noted research areas will require an extensive, interactive team approach. Personnel from the medical research,operational, developmental, and basic science communities will be essential to success.

Pepper, L. J.↗

NASA NTRS1996

The Role of Linear Acceleration in Visual-Vestibular Interactions and Implications in Aircraft Operations

While considerable attention has been given to visual-vestibular interaction (VVI) during angular motion of the head as might occur during an aircraft spin, much less attention has been given to VVI during linear motion of the head. Such interaction might occur, for example, while viewing a stationary or moving display during vertical take-off and landing operations Research into linear VVI, particularly during prolonged periods of linear acceleration, has been hampered by the unavailability of a programmable translator capable of large excursions We collaborated with Otis Elevator Co. and used their research tower and elevator, whose motion could be digitally programmed, to vertically translate human subjects over a distance of 92.3 meters with a peak linear acceleration of 2 meters/sec(exp 2) During pulsatile or sinusoidal translation, the subjects viewed moving stripes (optokinetic stimulus) or a fixed point source (light emitting diode, led, display), respectively and it was generally found that. The direction of linear acceleration relative to the cardinal head axes and the direction of the slow component of optokinetic nystagmus (OKN) determined the extent of VVI during concomitant stripe motion and linear acceleration. Acceleration along the z head axis (A(sub z)) produced the largest VVI, particularly when the slow component of OKN was in the same direction as eye movements produced by the linear acceleration and Eye movements produced by linear acceleration are suppressed by viewing a fixed target at frequencies below 10 Hz But, above this frequency the suppression produced by VVI is removed. Finally, as demonstrated in non-human primates, vergence of the eyes appears to modulate the vertical eye movement response to linear acceleration in humans.

Correia, Manning J.↗

NASA NTRS1995

[Development of Engineering Systems for Space Station Freedom]

From January, 1990 through September, 1995, Cleveland State University (CSU) and Lewis Research Center (LeRC) participated in a research cooperative agreement. Extensive study and experimentation were done by CSU on research technologies, methods, and techniques employed by the Space Station Freedom (SSF) project and, later, the Space Experiments Division (SED). In spite of many problems occasioned by the virtual cancellation of Space Station Freedom at LeRC, and organizational and financial problem at LeRC, CSU was able to do valuable work in the study and improvement of research operating methods there.

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NASA NTRS2000

Space Research, Education, and Related Activities in the Space Sciences

The Universities Space Research Association received an award of Cooperative Agreement #NCC5-356 on September 29, 1998. The mission of this activity, know as the Cooperative Program in Space Sciences (CPSS), is to conduct space science research and leading-edge instrumentation and technology development, enable research by the space sciences communities, and to expedite the effective dissemination of space science research, technology, data, and information to the educational community and the general public. To fulfill this mission, USRA recruits and maintains a staff of scientific researchers, operates a series of guest investigator facilities, organizes scientific meetings and workshops, and encourages various interactions with students and university faculty members.

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NASA NTRS2000

Spaceport Operations Element

This viewgraph presentation gives an overview of the spaceport operations element, including details on NASA Ames air traffic management technologies, reusable launch vehicles, space transportation of the future, and spaceport flight operations research topics.

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NASA NTRS2002

Space Research, Education, and Related Activities in the Space Sciences

The Universities Space Research Association received an award of Cooperative Agreement NCC5-356 on September 29, 1998. The mission of this activity, known as the Cooperative Program in Space Sciences (CPSS), is to conduct space science research and leading-edge instrumentation and technology development, enable research by the space sciences communities, and to expedite the effective dissemination of space science research, technology, data, and information to the educational community and the general public. To fulfill this mission, USRA recruits and maintains a staff of scientific researchers, operates a series of guest investigator facilities, organizes scientific meetings and workshops, and encourages various interactions with students and university faculty members.

Black, David↗

NASA NTRS1998

Credible Software and Simulation Uncertainty

The utility of software primarily depends on its reliability and performance; whereas, its significance depends solely on its credibility for intended use. The credibility of simulations confirms the credibility of software. The level of veracity and the level of validity of simulations determine the degree of credibility of simulations. The process of assessing this credibility in fields such as computational mechanics (CM) differs from that followed by the Defense Modeling and Simulation Office in operations research. Verification and validation (V&V) of CM simulations is not the same as V&V of CM software. Uncertainty is the measure of simulation credibility. Designers who use software are concerned with management of simulation uncertainty. Terminology and concepts are presented with a few examples from computational fluid dynamics.

Mehta, Unmeel B.↗

NASA NTRS2002

Space Research, Education, and Related Activities In the Space Sciences

The mission of this activity, known as the Cooperative Program in Space Sciences (CPSS), is to conduct space science research and leading-edge instrumentation and technology development, enable research by the space sciences communities, and to expedite the effective dissemination of space science research, technology, data, and information to the educational community and the general public. To fulfill this mission, the Universities Space Research Association (USRA) recruits and maintains a staff of scientific researchers, operates a series of guest investigator facilities, organizes scientific meetings and workshops, and encourages various interactions with students and university faculty members. This paper is the final report from this now completed Cooperative Agreement.

Black, David↗

NASA NTRS2003

Cooperative Program In Space Science

The mission of this activity, know as the Cooperative Program in Space Sciences (CPSS), is to conduct space science research and leading-edge instrumentation and technology development, enable research by the space sciences communities, and to expedite the effective dissemination of space science research, technology, data, and information to the educational community and the general public. To fulfill this mission, USRA recruits and maintains a staff of scientific researchers, operates a series of guest investigator facilities, organizes scientific meetings and workshops, and encourages various interactions with students and university faculty members.

Black, David↗

NASA NTRS1999

Non-Traditional Displays for Mission Monitoring

Advances in automation capability and reliability have changed the role of humans from operating and controlling processes to simply monitoring them for anomalies. However, humans are traditionally bad monitors of highly reliable systems over time. Thus, the human is assigned a task for which he is ill equipped. We believe that this has led to the dominance of human error in process control activities such as operating transportation systems (aircraft and trains), monitoring patient health in the medical industry, and controlling plant operations. Research has shown, though, that an automated monitor can assist humans in recognizing and dealing with failures. One possible solution to this predicament is to use a polar-star display that will show deviations from normal states based on parameters that are most indicative of mission health.

Trujillo, Anna C.↗

NASA NTRS2003

An Application of the Methodology for Assessment of the Sustainability of Air Transport System

An assessment and operationalization of the concept of sustainable air transport system is recognized as an important but complex research, operational and policy task. In the scope of the academic efforts to properly address the problem, this paper aims to assess the sustainability of air transport system. It particular, the paper describes the methodology for assessment of sustainability and its potential application. The methodology consists of the indicator systems, which relate to the air transport system operational, economic, social and environmental dimension of performance. The particular indicator systems are relevant for the particular actors such users (air travellers), air transport operators, aerospace manufacturers, local communities, governmental authorities at different levels (local, national, international), international air transport associations, pressure groups and public. In the scope of application of the methodology, the specific cases are selected to estimate the particular indicators, and thus to assess the system sustainability under given conditions.

Janic, Milan↗

NASA NTRS2005

Systemic Analysis Approaches for Air Transportation

Air transportation system designers have had only limited success using traditional operations research and parametric modeling approaches in their analyses of innovations. They need a systemic methodology for modeling of safety-critical infrastructure that is comprehensive, objective, and sufficiently concrete, yet simple enough to be used with reasonable investment. The methodology must also be amenable to quantitative analysis so issues of system safety and stability can be rigorously addressed. However, air transportation has proven itself an extensive, complex system whose behavior is difficult to describe, no less predict. There is a wide range of system analysis techniques available, but some are more appropriate for certain applications than others. Specifically in the area of complex system analysis, the literature suggests that both agent-based models and network analysis techniques may be useful. This paper discusses the theoretical basis for each approach in these applications, and explores their historic and potential further use for air transportation analysis.

Conway, Sheila↗

NASA NTRS2005

STS-114: Multi-Cut Profiles and Mission Overviews

Profiles of the seven crewmembers of the STS-114 Discovery are shown. Eileen Collins, Commander, talks about her fascination with flying as a young child and her eagerness to have someone teach her to fly at age 19. Her eagerness and hard work earned her a master's in operations research from Stanford University in 1986 and a master's in space systems management from Webster University in 1989. Jim Kelly, Pilot, talks about his desire to become an astronaut at a very young age. Charles Camarda, Mission Specialist, always wanted to become an astronaut and earned a Bachelor's degree in aerospace engineering from Polytechnic Institute of Brooklyn in 1974, a Master's in engineering Science from George Washington University in 1980 and a doctorate in aerospace engineering from Virginia Polytechnic Institute and State University in 1990. Wendy Lawrence, Mission Specialist decided that she wanted to become an astronaut when she saw the first man to walk on the moon. Soichi Noguchi, Mission Specialist from JAXA expresses that people like scientists, doctors and engineers could fly and he also wanted to venture into spaceflight. Steve Robinson, Mission Specialist says that he was fascinated with things that flew as a child and wanted to make things fly. Australian born Andrew Thomas, Mission Specialist wanted to become an astronaut as a young boy but never realized that he would fulfill his dream. The crewmember profiles end with an overview of the STS-114 Discovery mission. Paul Hill, Lead Flight Director talks about the main goal of the STS-114 mission which is to demonstrate that changes to the Orbiter and flight procedures are good and the second goal is to finish construction of the International Space Station. Sergei Krikalev, Commander talks about increasing the capability of the International Space Station, Jim Kelly discusses the work that is being performed in the external tank, Andy Thomas talks about procedures done to stop foam release and Soichi Noguchi discusses his duty to film the external tank after separation.

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NASA NTRS2004

Probability Distribution Estimated From the Minimum, Maximum, and Most Likely Values: Applied to Turbine Inlet Temperature Uncertainty

Modern engineering design practices are tending more toward the treatment of design parameters as random variables as opposed to fixed, or deterministic, values. The probabilistic design approach attempts to account for the uncertainty in design parameters by representing them as a distribution of values rather than as a single value. The motivations for this effort include preventing excessive overdesign as well as assessing and assuring reliability, both of which are important for aerospace applications. However, the determination of the probability distribution is a fundamental problem in reliability analysis. A random variable is often defined by the parameters of the theoretical distribution function that gives the best fit to experimental data. In many cases the distribution must be assumed from very limited information or data. Often the types of information that are available or reasonably estimated are the minimum, maximum, and most likely values of the design parameter. For these situations the beta distribution model is very convenient because the parameters that define the distribution can be easily determined from these three pieces of information. Widely used in the field of operations research, the beta model is very flexible and is also useful for estimating the mean and standard deviation of a random variable given only the aforementioned three values. However, an assumption is required to determine the four parameters of the beta distribution from only these three pieces of information (some of the more common distributions, like the normal, lognormal, gamma, and Weibull distributions, have two or three parameters). The conventional method assumes that the standard deviation is a certain fraction of the range. The beta parameters are then determined by solving a set of equations simultaneously. A new method developed in-house at the NASA Glenn Research Center assumes a value for one of the beta shape parameters based on an analogy with the normal distribution (ref.1). This new approach allows for a very simple and direct algebraic solution without restricting the standard deviation. The beta parameters obtained by the new method are comparable to the conventional method (and identical when the distribution is symmetrical). However, the proposed method generally produces a less peaked distribution with a slightly larger standard deviation (up to 7 percent) than the conventional method in cases where the distribution is asymmetric or skewed. The beta distribution model has now been implemented into the Fast Probability Integration (FPI) module used in the NESSUS computer code for probabilistic analyses of structures (ref. 2).

Holland, Frederic A., Jr.↗

NASA NTRS2004

Developing Advanced Support Technologies for Planetary Exploration Missions

The United States Vision for Space Exploration calls for sending robots and humans to explore the Earth s moon, the planet Mars, and beyond. The National Aeronautics and Space Administration (NASA) is developing a set of design reference missions that will provide further detail to these plans. Lunar missions are expected to provide a stepping stone, through operational research and evaluation, in developing the knowledge base necessary to send crews on long duration missions to Mars and other distant destinations. The NASA Exploration Systems Directorate (ExSD), in its program of bioastronautics research, manages the development of technologies that maintain human life, health, and performance in space. Using a systems engineering process and risk management methods, ExSD s Human Support Systems (HSS) Program selects and performs research and technology development in several critical areas and transfers the results of its efforts to NASA exploration mission/systems development programs in the form of developed technologies and new knowledge about the capabilities and constraints of systems required to support human existence beyond Low Earth Orbit. HSS efforts include the areas of advanced environmental monitoring and control, extravehicular activity, food technologies, life support systems, space human factors engineering, and systems integration of all these elements. The HSS Program provides a structured set of deliverable products to meet the needs of exploration programs. these products reduce the gaps that exist in our knowledge of and capabilities for human support for long duration, remote space missions. They also reduce the performance gap between the efficiency of current space systems and the greater efficiency that must be achieved to make human planetary exploration missions economically and logistically feasible. In conducting this research and technology development program, it is necessary for HSS technologists and program managers to develop a common currency for decision making and the allocation of funding. A high level assessment is made of both the knowledge gaps and the system performance gaps across the program s technical project portfolio. This allows decision making that assures proper emphasis areas and provides a key measure of annual technological progress, as exploration mission plans continue to mature.

Berdich, Debra P.↗

NASA NTRS2004

Developing Advanced Human Support Technologies for Planetary Exploration Missions

The United States Vision for Space Exploration calls for sending robots and humans to explore the Earth's moon, the planet Mars, and beyond. The National Aeronautics and Space Administration (NASA) is developing a set of design reference missions that will provide further detail to these plans. Lunar missions are expected to provide a stepping stone, through operational research and evaluation, in developing the knowledge base necessary to send crews on long duration missions to Mars and other distant destinations. The NASA Exploration Systems Directorate (ExSD), in its program of bioastronautics research, manages the development of technologies that maintain human life, health, and performance in space. Using a system engineering process and risk management methods, ExSD's Human Support Systems (HSS) Program selects and performs research and technology development in several critical areas and transfers the results of its efforts to NASA exploration mission/systems development programs in the form of developed technologies and new knowledge about the capabilities and constraints of systems required to support human existence beyond Low Earth Orbit. HSS efforts include the areas of advanced environmental monitoring and control, extravehicular activity, food technologies, life support systems, space human factors engineering, and systems integration of all these elements. The HSS Program provides a structured set of deliverable products to meet the needs of exploration programs. These products reduce the gaps that exist in our knowledge of and capabilities for human support for long duration, remote space missions. They also reduce the performance gap between the efficiency of current space systems and the greater efficiency that must be achieved to make human planetary exploration missions economically and logistically feasible. In conducting this research and technology development program, it is necessary for HSS technologists and program managers to develop a common currency for decision making and the allocation of funding. A high level assessment is made of both the knowledge gaps and the system performance gaps across the program s technical project portfolio. This allows decision making that assures proper emphasis areas and provides a key measure of annual technological progress, as exploration mission plans continue to mature.

Berdich, Debra P.↗