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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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All sourcesNASA NTRSDOE OSTI
NASA NTRS2009

The Establishment of a New Friction Stir Welding Process Development Facility at NASA/MSFC

Full-scale weld process development is being performed at MSFC to develop the tools, fixtures, and facilities necessary for Ares I production. Full scale development in-house at MSFC fosters technical acuity within the NASA engineering community, and allows engineers to identify and correct tooling and equipment shortcomings before they become problems on the production floor. Finally, while the new weld process development facility is currently being outfitted in support of Ares I development, it has been established to support all future Constellation Program needs. In particular, both the RWT and VWT were sized with the larger Ares V hardware in mind.

Carter, Robert W.↗
NASA NTRS1985

Measuring the impact of computer resource quality on the software development process and product

The availability and quality of computer resources during the software development process was speculated to have measurable, significant impact on the efficiency of the development process and the quality of the resulting product. Environment components such as the types of tools, machine responsiveness, and quantity of direct access storage may play a major role in the effort to produce the product and in its subsequent quality as measured by factors such as reliability and ease of maintenance. During the past six years, the NASA Goddard Space Flight Center has conducted experiments with software projects in an attempt to better understand the impact of software development methodologies, environments, and general technologies on the software process and product. Data was extracted and examined from nearly 50 software development projects. All were related to support of satellite flight dynamics ground-based computations. The relationship between computer resources and the software development process and product as exemplified by the subject NASA data was examined. Based upon the results, a number of computer resource-related implications are provided.

Mcgarry, Frank↗
NASA NTRS1988

Reasoning with case histories of process knowledge for efficient process development

The significance of compiling case histories of empirical process knowledge and the role of such histories in improving the efficiency of manufacturing process development is discussed in this paper. Methods of representing important investigations as cases and using the information from such cases to eliminate redundancy of empirical investigations in analogous process development situations are also discussed. A system is proposed that uses such methods to capture the problem-solving framework of the application domain. A conceptual design of the system is presented and discussed.

Bharwani, Seraj S.↗
NASA NTRS1990

Software Model Of Software-Development Process

Collection of computer programs constitutes software tool for simulation of medium- to large-scale software-development projects. Necessary to include easily identifiable and more-readily quantifiable characteristics like costs, times, and numbers of errors. Mathematical model incorporating these and other factors of dynamics of software-development process implemented in the Software Life Cycle Simulator (SLICS) computer program. Simulates dynamics of software-development process. In combination with input and output expert software systems and knowledge-based management software system, develops information for use in managing large software-development project. Intended to aid managers in planning, managing, and controlling software-development processes by reducing uncertainties in budgets, required personnel, and schedules.

Lin, Chi Y.↗
NASA NTRS2002

Preliminary Thermal-Mechanical Sizing of Metallic TPS: Process Development and Sensitivity Studies

The purpose of this research was to perform sensitivity studies and develop a process to perform thermal and structural analysis and sizing of the latest Metallic Thermal Protection System (TPS) developed at NASA LaRC (Langley Research Center). Metallic TPS is a key technology for reducing the cost of reusable launch vehicles (RLV), offering the combination of increased durability and competitive weights when compared to other systems. Accurate sizing of metallic TPS requires combined thermal and structural analysis. Initial sensitivity studies were conducted using transient one-dimensional finite element thermal analysis to determine the influence of various TPS and analysis parameters on TPS weight. The thermal analysis model was then used in combination with static deflection and failure mode analysis of the sandwich panel outer surface of the TPS to obtain minimum weight TPS configurations at three vehicle stations on the windward centerline of a representative RLV. The coupled nature of the analysis requires an iterative analysis process, which will be described herein. Findings from the sensitivity analysis are reported, along with TPS designs at the three RLV vehicle stations considered.

Poteet, Carl C.↗
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↗
DOE OSTI2022

Process development for recovering critical elements from acid mine drainage

The rapid development of advanced technologies has increased the demand for critical elements, such as Mn, Co, and Ni. For this work, a systematic study was conducted to develop a process for producing high-purity Mn, Co, and Ni products from an acid mine drainage (AMD). As major contaminants, Fe and Al in the solution were sequentially precipitated and eliminated by elevating the pH to around 4.00 and 6.50, respectively. After that, a pre-concentrated slurry containing 3,794 mg/L Mn, 59 mg/L Co, 127 mg/L Ni, and 300 mg/L Zn was obtained by collecting the precipitates formed in the pH range of 6.50 to 10.00. The pH of the pre-concentrated slurry was decreased to around 5.00 by adding HCl to re-dissolve Co, Ni, and Zn for further purification. At this pH, greater than 50% of Mn remained undissolved, and filtration of the undissolved material resulted in a product with around 30 wt.% Mn. Sodium sulfide was added into the re-dissolved solution to selectively precipitate Co, Ni, and Zn while remaining Mn in the solution. Almost 100% of Co, Ni, and Zn but only around 15% of Mn were precipitated using a sulfur to metal molar ratio of 1 at pH 4.00. The sulfide precipitate was calcined at 200 °C for 2 h and then completely dissolved in 1.2 M HCl. The critical elements existing in the dissolved solution were efficiently separated using a two-stage solvent extraction process. Ultimately, Co and Ni products with almost 94% and 100% purity were obtained by sulfide and alkaline precipitation, respectively.

42 ENGINEERING↗
NASA NTRS2006

The Cassini-Huygens Sequence Development Process

Each phase of the sequence development process had to overcome many operational challenges due to the immense complexity of the spacecraft, tour design, pointing capabilities, flight rules and software development. This paper will address the specific challenges related to each of those complexities and the methods used to overcome them during operation.

science planning↗
NASA NTRS1985

Process development

An overview is given of seven process development activities which were presented at this session. Pulsed excimer laser processing of photovoltaic cells was presented. A different pulsed excimer laser annealing was described using a 50 w laser. Diffusion barrier research focused on lowering the chemical reactivity of amorphous thin film on silicon. In another effort adherent and conductive films were successfully achieved. Other efforts were aimed at achieving a simultaneous front and back junction. Microwave enhanced plasma deposition experiments were performed. An updated version of the Solar Array Manufacturing Industry Costing Standards (SAMICS) was presented, along with a life cycle cost analysis of high efficiency cells. The last presentation was on the evaluation of the ethyl vinyl acetate encapsulating system.

Bickler, D. B.↗
NASA NTRS2008

Three-dimensional cell to tissue development process

An improved three-dimensional cell to tissue development process using a specific time varying electromagnetic force, pulsed, square wave, with minimum fluid shear stress, freedom for 3-dimensional spatial orientation of the suspended particles and localization of particles with differing or similar sedimentation properties in a similar spatial region.

Goodwin, Thomas J.↗
NASA NTRS1996

Operations engineering: Applying hands-on experience to the development process

The concepts behind operations engineering as applied to the requirements, design, development and testing of data processing systems are presented, together with the associated benefits. The objective of operations engineering is to reduce the overall life cycle costs by integrating operations experience with the development process. To achieve this goal, operations engineering seeks to reduce the development costs by that assuring operational requirements are incorporated into the design and development process as early as possible, and reduce the operational costs by decreasing operations staffing requirements and other related costs through improved system capabilities. The areas for improved system capabilities include: system recovery; data recovery; fault isolation; system operability; system flexibility; system automation; and system reporting. It is described how operations engineering is integrated with the development process, and the difficulties and misconceptions experienced in using operations engineering are discussed.

Alcott, Gary↗
NASA NTRS2005

New Deep Reactive Ion Etching Process Developed for the Microfabrication of Silicon Carbide

Silicon carbide (SiC) is a promising material for harsh environment sensors and electronics because it can enable such devices to withstand high temperatures and corrosive environments. Microfabrication techniques have been studied extensively in an effort to obtain the same flexibility of machining SiC that is possible for the fabrication of silicon devices. Bulk micromachining using deep reactive ion etching (DRIE) is attractive because it allows the fabrication of microstructures with high aspect ratios (etch depth divided by lateral feature size) in single-crystal or polycrystalline wafers. Previously, the Sensors and Electronics Branch of the NASA Glenn Research Center developed a DRIE process for SiC using the etchant gases sulfur hexafluoride (SF6) and argon (Ar). This process provides an adequate etch rate of 0.2 m/min and yields a smooth surface at the etch bottom. However, the etch sidewalls are rougher than desired, as shown in the preceding photomicrograph. Furthermore, the resulting structures have sides that slope inwards, rather than being precisely vertical. A new DRIE process for SiC was developed at Glenn that produces smooth, vertical sidewalls, while maintaining an adequately high etch rate.

Evans, Laura J.↗
NASA NTRS1993

Automating the training development process

The Automated Training Development System (ATDS) was developed as a training tool for the JPL training environment. ATDS is based on the standard for military training programs and is designed to develop training from a system perspective, focusing on components in terms of the whole process. The principal feature of ATDS is data base maintainability. Everything is contained and maintained within the data base, and, if properly developed, it could be a training component of a software delivery and provided to CM as a controlled item. The analysis, development, design, presentation, and reporting phases in the ATDS instructional design method are illustrated.

Scott, Carol J.↗
NASA NTRS1989

Computer-aided software development process design

The authors describe an intelligent tool designed to aid managers of software development projects in planning, managing, and controlling the development process of medium- to large-scale software projects. Its purpose is to reduce uncertainties in the budget, personnel, and schedule planning of software development projects. It is based on dynamic model for the software development and maintenance life-cycle process. This dynamic process is composed of a number of time-varying, interacting developmental phases, each characterized by its intended functions and requirements. System dynamics is used as a modeling methodology. The resulting Software LIfe-Cycle Simulator (SLICS) and the hybrid expert simulation system of which it is a subsystem are described.

Lin, Chi Y.↗
NASA NTRS2015

Review of Exploration Systems Development (ESD) Integrated Hazard Development Process: Appendices - Volume 1

The Chief Engineer of the Exploration Systems Development (ESD) Office requested that the NASA Engineering and Safety Center (NESC) perform an independent assessment of the ESD's integrated hazard development process. The focus of the assessment was to review the integrated hazard analysis (IHA) process and identify any gaps/improvements in the process (e.g., missed causes, cause tree completeness, missed hazards). This document contains the outcome of the NESC assessment.

Smiles, Michael D.↗
NASA NTRS2015

Review of Exploration Systems Development (ESD) Integrated Hazard Development Process: Volume 2 - Appendices

The Chief Engineer of the Exploration Systems Development (ESD) Office requested that the NASA Engineering and Safety Center (NESC) perform an independent assessment of the ESD's integrated hazard development process. The focus of the assessment was to review the integrated hazard analysis (IHA) process and identify any gaps/improvements in the process (e.g. missed causes, cause tree completeness, missed hazards). This document contains the outcome of the NESC assessment.

Smiles, Michael D.↗