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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 91 records · Page 5

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NASA NTRS1991

NASA/Ames Research Center DC-8 data system

In-flight facility data acquisition, distribution, and recording on the NASA Ames Research Center (ARC) DC-8 are performed by the Data Acquisition and Distribution System (DADS). Navigational and environmental data collected by the DADS are converted to engineering units and distributed real-time to investigator stations once per second. Selected engineering units data are printed and displayed on closed circuit television monitors throughout flights. An in-flight graphical display of the DC-8 flight track (with barbs indicating wind direction and magnitude) has recently been added to the DADS capabilities. Logging of data run starts/stops and commentary from the mission director are also provided. All data are recorded to hard disk in-flight and archived to tape medium post-flight. Post-flight, hard copies of the track map and mission director's log are created by the DADS. The DADS is a distributed system consisting of a data subsystem, an Avionic Serial Data-to-VMEbus (ASD2VME) subsystem, and a host subsystem. Each subsystem has a dedicated central processing unit (CPU) and is capable of stand-alone operation. All three subsystems are housed in a single 20-slot VME chassis and communicate with each other over the VMEbus. The data and host subsystems are briefly discussed, and the DC-8 DADS internal configuration and system block diagram are presented.

Cherniss, S. C.↗

NASA NTRS1993

An analysis of the history of dust activity on Mars

A comprehensive list of dust storm activity on Mars has been compiled from various published lists and additional data. For uniformity and clarity, each event is classified using a new system that includes a well-defined nomenclature. Maps showing the reported locations of events have been compiled. Detailed commentaries describe the events and/or circumstances of their observation. The seasonal distribution of Martian dust events is diagrammed and discussed together with a seasonal and annual (Mars years) timeline that includes the frequency of photographic coverage. Regional dust storms tend to occur most frequently, and all planet-encircling dust storms have been observed during the southern spring and summer seasons, although there is significant interannual variability.

Martin, Leonard J.↗

NASA NTRS1993

Things that go bump in the light - On the optical specification of contact severity

Psychologists are intrigued with the idea that optical variables can specify not only the time until an object impacts an observer but also the severity of the impact. However, the mapping between the optical variables and the kinematic variables has been misstated, erroneously implying that there exist critical values of the optical variables used for locomotion and control. In this commentary, the mathematical relationship between the optical and kinematic variables is reexamined and the erroneous assumptions that have led to the proposal of critical values are shown. Also examined are the empirical data on deceleration to approach to assess whether the proposed optical variables are likely candidates for control strategies. Finally, problems associated with numerical approximations to dynamic systems, particularly when analytic solutions exist, are discussed.

Kaiser, Mary K.↗

NASA NTRS1978

A joint university-government technical editing program

The NASA Langley Research Center (LaRC) and Old Dominion University have designed a mutually useful technical editing program. A university team made up of an English instructor and two graduate students - one from English, one from engineering - works with a senior editor from LaRC to prepare technical reports for publication. A round-robin technique gives the university team editorial commentary from both language and technical specialists; the senior editor from LaRC supervises reports through final publication. To date, the system has provided LaRC with a respectable product and university students with valuable on-the-job training.

Stohrer, Freda F.↗

NASA NTRS1993

United States/Russia Space Cooperation Documentary

This video documents the initiative to develop a multinational, permanent space research laboratory. Historical background on the U.S. and Soviet manned space flight program as well as joint efforts such as the Apollo-Soyuz link up is shown. The current initiative will begin with collaborative missions involving NASA's space shuttle and Russia's Mir space station, and culminate in a permanently manned space station involving the U.S., Russia, Japan, Canada, and ESA. Shown are computer simulations of the proposed space station. Commentary is provided by the NASA administrator, former astronauts, cosmonauts, and Russian and American space experts.

Source record↗

NASA NTRS1995

Earth observations from space: History, promise, and reality. Executive summary

In this report the Committee on Earth Studies (CES), a standing committee of the Space Studies Board (SSB) within the National Research Council (NRC), reviews the recent history (nominally from 1981 to 1995) of the U.S. earth observations programs that serve civilian needs. The principal observations programs examined are those of NASA and the National Oceanic and Atmospheric Administration (NOAA). The Air Force' s Defense Meteorological Satellite Program (DMSP) is discussed, but only from the perspective of its relationship to civil needs and the planned merger with the NOAA polar-orbiting system. The report also reviews the interfaces between the earth observations satellite programs and the major national and international environmental monitoring and research programs. The monitoring and research programs discussed are the U.S. Global Change Research Program (USGCRP), the International Geosphere-Biosphere Program (IGBP), the World Climate Research Program (WCRP), related international scientific campaigns, and operational programs for the sharing and application of environmental data. The purpose of this report is to provide a broad historical review and commentary based on the views of the CES members, with particular emphasis on tracing the lengthy record of advisory committee recommendations. Any individual topic could be the subject of an extended report in its own right. Indeed, extensive further reviews are already under way to that end. If the CES has succeeded in the task it has undertaken. This report will serve as a useful starting point for any such more intensive study. The report is divided into eight chapters: ( I ) an introduction, (2) the evolution of the MTPE, (3) its relationship to the USGCRP, (4) applications of earth observations data, (5) the role that smaller satellites can play in research and operational remote sensing, (6) earth system modeling and information systems, (7) a number of associated activities that contribute to the MTPE and the USGCRP, and (8) organizational issues in the conduct of civil earth observations programs. Following the body of the report is a series of appendixes: after a list of acronyms and abbreviations and collected short biographies of CES members, six brief tutorials discuss several scientific topics important to the science and applications of earth observations. Highlights from the eight chapters follow.

Source record↗

NASA NTRS2001

D3: A Collaborative Infrastructure for Aerospace Design

Walton, Joan↗

NASA NTRS2003

Tensegrity I. Cell structure and hierarchical systems biology

In 1993, a Commentary in this journal described how a simple mechanical model of cell structure based on tensegrity architecture can help to explain how cell shape, movement and cytoskeletal mechanics are controlled, as well as how cells sense and respond to mechanical forces (J. Cell Sci. 104, 613-627). The cellular tensegrity model can now be revisited and placed in context of new advances in our understanding of cell structure, biological networks and mechanoregulation that have been made over the past decade. Recent work provides strong evidence to support the use of tensegrity by cells, and mathematical formulations of the model predict many aspects of cell behavior. In addition, development of the tensegrity theory and its translation into mathematical terms are beginning to allow us to define the relationship between mechanics and biochemistry at the molecular level and to attack the larger problem of biological complexity. Part I of this two-part article covers the evidence for cellular tensegrity at the molecular level and describes how this building system may provide a structural basis for the hierarchical organization of living systems--from molecule to organism. Part II, which focuses on how these structural networks influence information processing networks, appears in the next issue.

NASA Program Fundamental Space Biology↗

NASA NTRS2002

The D3 Middleware Architecture

DARWIN is a NASA developed, Internet-based system for enabling aerospace researchers to securely and remotely access and collaborate on the analysis of aerospace vehicle design data, primarily the results of wind-tunnel testing and numeric (e.g., computational fluid-dynamics) model executions. DARWIN captures, stores and indexes data; manages derived knowledge (such as visualizations across multiple datasets); and provides an environment for designers to collaborate in the analysis of test results. DARWIN is an interesting application because it supports high-volumes of data. integrates multiple modalities of data display (e.g., images and data visualizations), and provides non-trivial access control mechanisms. DARWIN enables collaboration by allowing not only sharing visualizations of data, but also commentary about and views of data. Here we provide an overview of the architecture of D3, the third generation of DARWIN. Earlier versions of DARWIN were characterized by browser-based interfaces and a hodge-podge of server technologies: CGI scripts, applets, PERL, and so forth. But browsers proved difficult to control, and a proliferation of computational mechanisms proved inefficient and difficult to maintain. D3 substitutes a pure-Java approach for that medley: A Java client communicates (though RMI over HTTPS) with a Java-based application server. Code on the server accesses information from JDBC databases, distributed LDAP security services, and a collaborative information system. D3 is a three tier-architecture, but unlike 'E-commerce' applications, the data usage pattern suggests different strategies than traditional Enterprise Java Beans - we need to move volumes of related data together, considerable processing happens on the client, and the 'business logic' on the server-side is primarily data integration and collaboration. With D3, we are extending DARWIN to handle other data domains and to be a distributed system, where a single login allows a user transparent access to test results from multiple servers and authority domains.

Walton, Joan↗

NASA NTRS2005

"The Evolution of Photosynthesis and the Transition from an Anaerobic to an Aerobic World"

This project was focused on elucidating the evolution of photosynthesis, in particular the evolutionary developments that preceded and accompanied the transition from anoxygenic to oxygenic photosynthesis. Development of this process has clearly been of central importance to evolution of life on Earth. Photosynthesis is the mechanism that ultimately provides for the energy needs of most surface-dwelling organisms. Eukaryotic organisms are absolutely dependent on the molecular oxygen that has been produced by oxygenic photosynthesis. In this project we have employed a multidisciplinary approach to understand some of the processes that took place during the evolution of photosynthesis. In this project, we made excellent progress in the overall area of understanding the origin and evolution of photosynthesis. Particular progress has been made on several more specific research questions, including the molecular evolutionary analysis of photosynthetic components and biosynthetic pathways (2,3, 5, 7, 10), as well as biochemical characterization of electron transfer proteins related to photosynthesis and active oxygen protection (4,6,9). Finally, several review and commentary papers have been published (1, 8, 1 1). A total of twelve publications arose out of this grant, references to which are given below. Some specific areas of progress are highlighted and discussed in more detail.

Blankenship, Robert E.↗

NASA NTRS2006

The Molecular Ecology of Guerrero Negro: Justifying the Need for Environmental Genomics

The record of life on the only planet where it is known to exist is contained in the biogeochemical processes that organisms catalyze for their survival, in the compounds that they produce, and in their phylogenetic (evolutionary) relationships to each other. We manipulated sulfate and nutrient concentrations in intact microbial mats over periods of time up to a year. The objectives of the manipulations were: 1) characterize the diversity of process-associated functional genes; 2) understand environmental conditions leading to shifts in microbial guilds; 3) monitor/identify competitive responses of organisms sharing a metabolic niche. Characterization of functional genes associated with carbon (mcrA), nitrogen (nifH, nirK) and sulfur (dsrkB) cycling performed to date provided insight into the diversity and metabolic potential of the system; however, we only identified broad scale correlations between gene abundances and changes in mat physiology. For instance, increases in methane production by mats subjected to lowered sulfate and salinity concentrations were correlated with an observed increase in abundance of hydrogenotroph-like mcrA genes. However, due to low sequence similarity to any cultured isolates, phylogenetic associations only allow order level taxonomic commentary, preventing any associations being made on the cellular level. In each of the genes characterized from these experiments, a significant portion of sequences recovered show minimal phylogenetic affiliation to cultured organisms, preventing any understanding of inter-community dynamics and the functional capacities of these unknown organisms. Environmental genomics may provide insight into mat systems by allowing the correlation of functional genes with phylogenetic markers.

Smith, Jason M.↗

NASA NTRS2008

Stability and Controls Analysis and Flight Test Results of a 24-Foot Telescoping Nose Boom on an F-15B Airplane

The Quiet Spike(TradeMark) F-15B flight research program investigated supersonic shock reduction using a 24-ft telescoping nose boom on an F-15B airplane. The program goal was to collect flight data for model validation up to 1.8 Mach. In the area of stability and controls, the primary concerns were to assess the potential destabilizing effect of the oversized nose boom on the stability, controllability, and handling qualities of the airplane and to ensure adequate stability margins across the entire research flight envelope. This paper reports on the stability and control analytical methods, flight envelope clearance approach, and flight test results of the F-15B telescoping nose boom configuration. Also discussed are brief pilot commentary on typical piloting tasks and refueling tasks.

Moua, Cheng M.↗

NASA NTRS2009

Tool for Human-Systems Integration Assessment: HSI Scorecard

This paper describes the development and rationale for a human-systems integration (HSI) scorecard that can be used in reviews of vehicle specification and design. This tool can be used to assess whether specific HSI related criteria have been met as part of a project milestone or critical event, such as technical reviews, crew station reviews, mockup evaluations, or even review of major plans or processes. Examples of HSI related criteria include Human Performance Capabilities, Health Management, Human System Interfaces, Anthropometry and Biomechanics, and Natural and Induced Environments. The tool is not intended to evaluate requirements compliance and verification, but to review how well the human related systems have been considered for the specific event and to identify gaps and vulnerabilities from an HSI perspective. The scorecard offers common basis, and criteria for discussions among system managers, evaluators, and design engineers. Furthermore, the scorecard items highlight the main areas of system development that need to be followed during system lifecycle. The ratings provide a repeatable quantitative measure to what has been often seen as only subjective commentary. Thus, the scorecard is anticipated to be a useful HSI tool to communicate review results to the institutional and the project office management.

Whitmore, Nihriban↗

NASA NTRS2007

Flight Test Results on the Stability and Control of the F-15B Quiet Spike Aircraft

The Quiet Spike (QS) flight research program was an aerodynamic and structural proof-of-concept of a telescoping sonic-boom suppressing nose boom on an F-15 B aircraft. The program goal was to collect flight data for model validation up to 1.8 Mach. The primary test philosophy was maintaining safety of flight. In the area of stability and controls the primary concerns were to assess the potential destabilizing effect of the spike on the stability, controllability, and handling qualities of the aircraft and to ensure adequate stability margins across the entire QS flight envelop. This paper reports on the stability and control methods used for flight envelope clearance and flight test results of the F-15B Quiet Spike. Also discussed are the flight test approach, the criteria to proceed to the next flight condition, brief pilot commentary on typical piloting tasks, approach and landing, and refueling task, and air data sensitivity to the flight control system.

Moua, Cheng↗

NASA NTRS2009

Unmanned Aerial Vehicle Systems for Disaster Relief: Tornado Alley

Unmanned aerial vehicle systems are currently in limited use for public service missions worldwide. Development of civil unmanned technology in the United States currently lags behind military unmanned technology development in part because of unresolved regulatory and technological issues. Civil unmanned aerial vehicle systems have potential to augment disaster relief and emergency response efforts. Optimal design of aerial systems for such applications will lead to unmanned vehicles which provide maximum potentiality for relief and emergency response while accounting for public safety concerns and regulatory requirements. A case study is presented that demonstrates application of a civil unmanned system to a disaster relief mission with the intent on saving lives. The concept utilizes unmanned aircraft to obtain advanced warning and damage assessments for tornados and severe thunderstorms. Overview of a tornado watch mission architecture as well as commentary on risk, cost, need for, and design tradeoffs for unmanned aerial systems are provided.

DeBusk, Wesley M.↗

NASA NTRS2011

Data Analysis Techniques for a Lunar Surface Navigation System Testbed

NASA is interested in finding new methods of surface navigation to allow astronauts to navigate on the lunar surface. In support of the Vision for Space Exploration, the NASA Glenn Research Center developed the Lunar Extra-Vehicular Activity Crewmember Location Determination System and performed testing at the Desert Research and Technology Studies event in 2009. A significant amount of sensor data was recorded during nine tests performed with six test subjects. This paper provides the procedure, formulas, and techniques for data analysis, as well as commentary on applications.

Chelmins, David↗

NASA NTRS2012

Potential Applications of Modularity to Enable a Deep Space Habitation Capability for Future Human Exploration Beyond Low-Earth Orbit

Evaluating preliminary concepts of a Deep Space Habitat (DSH) enabling long duration crewed exploration of asteroids, the Moon, and Mars is a technically challenging problem. Sufficient habitat volumes and equipment, necessary to ensure crew health and functionality, increase propellant requirements and decrease launch flexibility to deliver multiple elements on a single launch vehicle; both of which increase overall mission cost. Applying modularity in the design of the habitat structures and subsystems can alleviate these difficulties by spreading the build-up of the overall habitation capability across several smaller parts. This allows for a more flexible habitation approach that accommodates various crew mission durations and levels of functionality. This paper provides a technical analysis of how various modular habitation approaches can impact the parametric design of a DSH with potential benefits in mass, packaging volume, and architectural flexibility. This includes a description of the desired long duration habitation capability, the definition of a baseline model for comparison, a small trade study to investigate alternatives, and commentary on potentially advantageous configurations to enable different levels of habitability. The approaches investigated include modular pressure vessel strategies, modular subsystems, and modular manufacturing approaches to habitat structure. The paper also comments upon the possibility of an integrated habitation strategy using modular components to create all short and long duration habitation elements required in the current exploration architectures.

Simon, Matthew A.↗

NASA NTRS2012

Flight Test Results on the Stability and Control of the F-15 Quiet Spike(TradeMark) Aircraft

The Quiet Spike F-15B flight research program investigated supersonic shock reduction using a 24-ft sub-scale telescoping nose boom on an F-15B airplane. The program primary flight test objective was to collect flight data for aerodynamic and structural models validation up to 1.8 Mach. Other objectives were to validate the mechanical feasibility of a morphing fuselage at the operational conditions and determine the near-field shock wave characterization. The stability and controls objectives were to assess the effect of the spike on the stability, controllability, and handling qualities of the aircraft and to ensure adequate stability margins across the entire research flight envelop. The two main stability and controls issues were the effects of the telescoping nose boom influenced aerodynamics on the F-15B aircraft flight dynamics and air data and angle of attack sensors. This paper reports on the stability and controls flight envelope clearance methods and flight test analysis of the F-15B Quiet Spike. Brief pilot commentary on typical piloting tasks, approach and landing, refueling task, and air data sensitivity to the flight control system are also discussed in this report.

Moua, Cheng M.↗