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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 145 records · Page 8
All sourcesNASA NTRSDOE OSTI
NASA NTRS2018

Far-Field Lorenz-Mie Scattering in an Absorbing Host Medium: Theoretical Formalism and FORTRAN Program

In this paper we make practical use of the recently developed first-principles approach to electromagnetic scattering by particles immersed in an unbounded absorbing host medium. Specifically, we introduce an actual computational tool for the calculation of pertinent far-field optical observables in the context of the classical Lorenzâ€"Mie theory. The paper summarizes the relevant theoretical formalism, explains various aspects of the corresponding numerical algorithm, specifies the input and output parameters of a FORTRAN program available at https://www.giss.nasa.gov/staff/mmishchenko/Lorenz-Mie.html, and tabulates benchmark results useful for testing purposes. This public-domain FORTRAN program enables one to solve the following two important problems: (i) simulate theoretically the reading of a remote well-collimated radiometer measuring electromagnetic scattering by an individual spherical particle or a small random group of spherical particles; and (ii) compute the single-scattering parameters that enter the vector radiative transfer equation derived directly from the Maxwell equations.

Far-field electromagnetic scattering; Absorbing ho↗
NASA NTRS1998

Practice Oriented Master's in Optics

The development of an interdisciplinary Masters Program with a concentration in Optics and Photonics Technology has been is described. This program was developed under the U.S. Manufacturing Education and Training Activity of the Technology Reinvestment Project. This development was a collaboration between the University of Alabama in Huntsville (UAH), Alabama A&M University, Northwest Shoals Community College, the NASA Marshall Space Flight Center (MSFC), the U.S. Army Missile Command, Oak Ridge National Laboratory (ORNL), Advanced Optical Systems Inc., Dynetics, Inc., Hughes Danbury Optical Systems, Inc., Nichols Research and Speedring Inc. These organizations as well as the National Institute for Standards and Technology and SCI, Inc. have been participating fully in the design, development and implementation of this program. This goal of the program is to produce highly trained graduates who can also solve practical problems. To this end, the program includes an on-site practicum at a manufacturing location. The broad curriculum of this program emphasizes the fundamentals of optics, optical systems manufacturing and testing, and the principles of design and manufacturing to cost for commercial products. The Master's of Science (MS) in Physics and Master's of Science in Engineering (MSE) in Electrical Engineering Degrees with concentration in Optics and Photonics Technology are offered by the respective UAH academic departments with support from and in consultation with a Steering Committee composed of representatives from each of the participating organizations, and a student representative from UAH. The origins of the programs are described. The curricula of the programs is described. The course outlines of the new courses which were developed for the new curriculum are included. Also included are samples of on-site practicums which the students have been involved in. Also included as attachments are samples of the advertisements, which includes flyers, and the program description given to prospective students. The expenditures in the development and information about the cost sharing among the participating organizations is also included. Finally a listing membership of the steering committee is attached.

Dimmock, John O.↗
NASA NTRS1971

The practical application of mishap data in Army aircraft system safety programs

The means are discussed by which the the United States Army Board for Aviation Accident Research (USABAAR) now utilizes the vast store of historical accident data in the application of the system safety concept for developmental aircraft. USABAAR serves as the central agency for the Army Accident Prevention Program which includes the receipt, processing, and analysis of all data and information related to Army aircraft accident experience. It is pointed out that methods which served the cause of accident prevention so well in the past are no longer adequate and that traditional parameters used to measure mishap experience have become obsolete. USABAAR has developed, and recently put into use, completely revised accident reporting forms which greatly expand the scope and detail of information provided as a result of investigation. This and other factors which have resulted in an improved data system are discussed in detail.

James T. Darrah, Jr↗
NASA NTRS1974

Testing of a flat conductor cable baseboard system for residential and commercial wiring

The results of extensive testing (mechanical, electrical, chemical, environmental, thermal, and analytical) are reported for a flat conductor cable baseboard system for residential and commercial wiring. In all of the tests, Underwriters Laboratories (UL) Standards, UL Tentative Test Programs, or Accepted Engineering Practices were followed during test selection, test setup, and test accomplishment.

Hankins, J. D.↗
NASA NTRS1975

Tug fleet and ground operations schedules and controls. Volume 2: part 2, addenda

The results of a study to assess the tug safing requirements at postlanding are presented. The study considered the normal (green light) conditions from orbiter landing to completion of preparations for the next launch. Normal tug ground turnaround operations include handling and transportation activities and the performance of inspections, tests, and checkout functions. These activities dictate that hazards to ground personnel, the tug, GSE, facilities, and ecology be reduced to the lowest practical level consistent with program objectives, cost, and schedules. During flight operations, the tug contains energy sources that constitute potential hazards but are required for mission accomplishment. These potential hazards have been reduced to an acceptable level for flight operation by design features and by providing for control of energy sources.

Source record↗
NASA NTRS1983

Ada and the NASA software environment

The NASA software, in broad categories, is described, and the software life cycle is characterized. Programming language policy and practices are reviewed. Applicability, benefits, and transition, as well as present and potential problems with Ada are examined.

Ng, E. W.↗
NASA NTRS1985

Strength of Graphite/Metal Composite Lap Joints

Report presents results of tests on fastened lap joints between strips of graphite/aluminum and graphite/magnesium composites. Goal of test program was to establish practical load range and effect of such joint parameters as load direction relative to graphite fiber direction, edge distance, fastener diameters, and lateral spacing as function of net section efficiency.

Ellison, A.↗
NASA NTRS1993

Reentry systems: Material technology needs

The material technology needs are: (1) lightweight and durable rigid insulating and higher temperature flexible materials; and (2) inspection, repair, producibility, and maintainability of refractory composites. The direction of efforts are: (1) funding base is relatively small for future years; (2) to minimize returns, collaborative programs appear to be practical; and (3) SSD's approach is to implement NASA developed technology.

Ehret, Richard Michael↗
NASA NTRS1993

An assessment of space shuttle flight software development processes

In early 1991, the National Aeronautics and Space Administration's (NASA's) Office of Space Flight commissioned the Aeronautics and Space Engineering Board (ASEB) of the National Research Council (NRC) to investigate the adequacy of the current process by which NASA develops and verifies changes and updates to the Space Shuttle flight software. The Committee for Review of Oversight Mechanisms for Space Shuttle Flight Software Processes was convened in Jan. 1992 to accomplish the following tasks: (1) review the entire flight software development process from the initial requirements definition phase to final implementation, including object code build and final machine loading; (2) review and critique NASA's independent verification and validation process and mechanisms, including NASA's established software development and testing standards; (3) determine the acceptability and adequacy of the complete flight software development process, including the embedded validation and verification processes through comparison with (1) generally accepted industry practices, and (2) generally accepted Department of Defense and/or other government practices (comparing NASA's program with organizations and projects having similar volumes of software development, software maturity, complexity, criticality, lines of code, and national standards); (4) consider whether independent verification and validation should continue. An overview of the study, independent verification and validation of critical software, and the Space Shuttle flight software development process are addressed. Findings and recommendations are presented.

Source record↗
NASA NTRS1995

Easing The Calculation Of Bolt-Circle Coordinates

Bolt Circle Calculation (BOLT-CALC) computer program used to reduce significant time consumed in manually computing trigonometry of rectangular Cartesian coordinates of holes in bolt circle as shown on blueprint or drawing. Eliminates risk of computational errors, particularly in cases involving many holes or in cases in which coordinates expressed to many significant digits. Program assists in many practical situations arising in machine shops. Written in BASIC. Also successfully compiled and implemented by use of Microsoft's QuickBasic v4.0.

Burley, Richard K.↗
NASA NTRS2006

2006 NASA Strategic Plan

On January 14, 2004, President George W. Bush announced A Renewed Spirit of Discovery: The President's Vision for U.S. Space Exploration, a new directive for the Nation's space program. The fundamental goal of this directive is "to advance U.S. scientific, security, and economic interests through a robust space exploration program." In issuing it, the President committed the Nation to a journey of exploring the solar system and beyond: returning to the Moon in the next decade, then venturing further into the solar system, ultimately sending humans to Mars and beyond. He challenged NASA to establish new and innovative programs to enhance understanding of the planets, to ask new questions, and to answer questions that are as old as humankind. NASA enthusiastically embraced the challenge of extending a human presence throughout the solar system as the Agency's Vision, and in the NASA Authorization Act of 2005, Congress endorsed the Vision for Space Exploration and provided additional guidance for implementation. NASA is committed to achieving this Vision and to making all changes necessary to ensure success and a smooth transition. These changes will include increasing internal collaboration, leveraging personnel and facilities, developing strong, healthy NASA Centers,a nd fostering a safe environment of respect and open communication for employees at all levels. NASA also will ensure clear accountability and solid program management and reporting practices. Over the next 10 years, NASA will focus on six Strategic Goals to move forward in achieving the Vision for Space Exploration. Each of the six Strategic Goals is clearly defined and supported by multi-year outcomes that will enhance NASA's ability to measure and report Agency accomplishments in this quest.

Source record↗
NASA NTRS2007

Emphasizing Spectrum Management for Sustainable Development Research and Applications in Disaster Management

NASA's spaceborne Earth and Heliospheric Observatories and airborne sensors provide a plethora of measurements. These measurements are used in science research to understand the climatology of our home planet and the solar fluxes and cycle of the only star in our solar system 'Sun' which is critical driver for the retention of life on Earth. Specifically, these measurements help us to understand the water and energy cycle, the carbon cycle, weather and climate, atmospheric chemistry, solar variability, and solid Earth and interior to feed into sophisticated mathematical models to analyze and predict the Earth's behavior as an integrated system. The main thrust of this research is on improving the prediction capability in the areas of weather, long term climate and solid Earth processes, and further help the humanity and future generations in terms of societal benefits in managing natural disasters, sustainability issues and many more. This work is further linked with our contributions in the Global Earth Observing System of Systems (GEOSS) Specifically, the data and knowledge resulting from the Earth observing systems and analytical models of the Earth can be made available for assimilation into decision support systems to serve society for disaster management. Through partnerships with national and international agencies and organizations, NASA's Science Mission Directorate's, Applied Sciences Program contributes to benchmarking practical uses of observations and predictions from Earth science remote sensing systems research. The objective is to establish innovative solutions using Earth observations and science information to provide decision support that can be adapted in applications of national and international priority. We along with the international community will continue this critical field of investigation by using our existing and future sensors from space, airborne and insitue environment. In our quest to expanding our knowledge, there will be a need for deploying additional sensors to obtain high spatial, temporal and spectral resolution measurements. These sensors operate in multiple spectral band ranging from UV, visible, infrared, microwave and radio frequency ranges. Of a particular concern is the microwave frequency bands which play a key role in land, ocean, moisture sensing. This is because of a growing commercial demand in the area of high speed broadband communication all over the world, the electronic manufacturers are looking into high frequency microwave spectral bands. This may present a risk to the remote sensing sensors because of additional sources of noise that can impair the highly sensitive passive remote sensing instruments.

Ambrose, Stephen↗
NASA NTRSDate not supplied

Pathfinder Networks for Measuring Operator Mental Model Structure with a Simple Autopilot System

Pathfinder networks are a method to represent mental models from empirically generated pairwise relatedness ratings. This study examined the effects of training exposure on mental model structures based on relatedness ratings collected using the Target Rating method. Forty-eight participants read instruction slides with or without explicit information on the functionality of an autopilot system (Advanced Mental Model or Basic Mental Model groups, respectively). Participants provided relatedness ratings and completed a comprehension test. The Advanced Mental Model group had more common links with the expected model, higher within-group network similarity scores, and higher mental model assessment questionnaire scores than the Basic Mental Model group. Both groups had coherence scores above the minimum threshold for internal consistency. Pathfinder network analysis was sensitive to changes produced by a simple exposure training intervention. In practice, a simple training program may effectively influence operator mental models in novel technological environments such as Advanced Air Mobility.

Mental Models↗
NASA NTRSDate not supplied

Crew Health and Performance (CHP) Technology Roadmaps

The Environmental Control and Life Support System (ECLSS) – Crew Health and Performance (CHP) Systems Capability Leadership Team (SCLT) is a community of practice (not a funded program) sponsored by Headquarters to develop, retain, and infuse the ECLSS and CHP capabilities necessary to enable the human exploration of the Moon and Mars through the integration and empowerment of experts across NASA, other government agencies, commercial industry, and academia. The goals of the SCLT are as follows: Use the Architecture Definition Document use cases and functions to identify gaps in NASA’s current technological capabilities to meet Agency objectives and develop strategies and roadmaps for closing such gaps Make technical/strategic recommendations on ECLSS and CHP technology development efforts and investments for PPBE, acquisition strategies, and leveraging NASA’s critical capabilities Establish key performance parameters and participate in key program and project reviews Maintain cognizance of relevant ECLSS and CHP national and international technology activities in government, industry, and academia, specifically, emerging innovations and technologies, trends, and opportunities Coordinate with commercial and international partners to identify areas of mutual interest and cooperation Support future mission and system architecture studies for human exploration This document is intended to be a comprehensive overview of the strategic development plans, or Roadmaps, of key technologies and capabilities identified by the SCLT. Each Roadmap is organized by Capability Gap as the gap name and number appears in STARPort, follows a fiscal year timeline, and displays any additional information on milestones, decision points, or important details on the right-hand side of the page. The Roadmaps should be used to facilitate discussion, decision making, and planning for programs and development projects, but are not expected to accurately depict the details and statuses of the projects and tasks appearing within the plans.

Human Health and Performance↗
NASA NTRSDate not supplied

The Future of Integrated Performance Modeling in the Crew Health and Performance – Probabilistic Risk Assessment Project

The NASA engineering community utilizes event-driven and fault-tree probabilistic techniques to classify risks in the space environment by taking advantage of the inherent knowledge of complex spaceflight system design and testing to quantify failure risk. In harmonizing the risk of human space flight, answering the question of ‘How do we balance health, performance and resource risks with other engineering risks on long duration space missions?’ remains a deeply challenging and largely qualitative practice. The Human Research Program’s Medical Extensible Dynamic Probabilistic Risk Assessment Tool (MEDPRAT) was a significant step forward in efforts to robustly quantify the risk to crew health for exploration missions. However, there remains a significant gap in the ability to comprehensively assess and characterize risk across the disparate functionalities and capabilities which comprise the Crew Health and Performance (CHP) system. The Crew Health and Performance – Probabilistic Risk Assessment (CHP-PRA) project seeks to characterize CHP risks by expanding beyond the foundation established by its PRA predecessors like IMM and MEDPRAT, that simulate medical risk metrics like loss of crew life and evacuations. One of the new risk measures in the CHP-PRA system is embodied in our Performance Risk Model (PRisM). PRisM provides a novel way of assessing crew performance on mission tasks, using a generalized framework which relates back to NASA-STD-3001. This approach allows PRisM to capture and integrate data from a variety of different domains into a single, unified, reproducible representation of astronaut performance. In this presentation, we discuss the motivation for the CHP-PRA work and give a high level overview of the goals of the project, outline the forward work for PRisM, and discuss collaboration opportunities for the community who might explore if their domain knowledge and data could be represented, integrated, and quantified with these tools, whose outcomes are metrics useful for supporting operational mission planning and decision making.

Lauren McIntyre↗
NASA NTRS1972

Simulation, Manual and Computerized (SMAC)

The guiding concept was to develop a simulation modeling method which can be quickly taught and learned, yet can be used to solve significant real world problems. SMAC consists of two manual simulation methods and one computer program. One of the manual methods is designed to impart an understanding of simulation; the other is designed to be a practical simulation method. The computer program will simulate queueing situations with up to five parallel servers or up to three series servers. The program is built around GASP 2A routines and retains the 8K capability of GASP.

Parker, M. W.↗