Search NASA⌕ Search

SEARCH · Search NASA

Results for “program implementation”

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.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 703 records · Page 39

Wall Interference in Two-Dimensional Wind Tunnels

Viscosity and tunnel-wall constraints introduced via boundary conditions. TWINTN4 computer program developed to implement method of posttest assessment of wall interference in two-dimensional wind tunnels. Offers two methods for combining sidewall boundary-layer effects with upper and lower wall interference. In sequential procedure, Sewall method used to define flow free of sidewall effects, then assessed for upper and lower wall effects. In unified procedure, wind-tunnel flow equations altered to incorporate effects from all four walls at once. Program written in FORTRAN IV for batch execution.

Kemp, William B., Jr.↗

Software packager user's guide

Software integration is a growing area of concern for many programmers and software managers because the need to build new programs quickly from existing components is greater than ever. This includes building versions of software products for multiple hardware platforms and operating systems, building programs from components written in different languages, and building systems from components that must execute on different machines in a distributed network. The goal of software integration is to make building new programs from existing components more seamless -- programmers should pay minimal attention to the underlying configuration issues involved. Libraries of reusable components and classes are important tools but only partial solutions to software development problems. Even though software components may have compatible interfaces, there may be other reasons, such as differences between execution environments, why they cannot be integrated. Often, components must be adapted or reimplemented to fit into another application because of implementation differences -- they are implemented in different programming languages, dependent on different operating system resources, or must execute on different physical machines. The software packager is a tool that allows programmers to deal with interfaces between software components and ignore complex integration details. The packager takes modular descriptions of the structure of a software system written in the package specification language and produces an integration program in the form of a makefile. If complex integration tools are needed to integrate a set of components, such as remote procedure call stubs, their use is implied by the packager automatically and stub generation tools are invoked in the corresponding makefile. The programmer deals only with the components themselves and not the details of how to build the system on any given platform.

Callahan, John R.↗

Improvements to the adaptive maneuvering logic program

The Adaptive Maneuvering Logic (AML) computer program simulates close-in, one-on-one air-to-air combat between two fighter aircraft. Three important improvements are described. First, the previously available versions of AML were examined for their suitability as a baseline program. The selected program was then revised to eliminate some programming bugs which were uncovered over the years. A listing of this baseline program is included. Second, the equations governing the motion of the aircraft were completely revised. This resulted in a model with substantially higher fidelity than the original equations of motion provided. It also completely eliminated the over-the-top problem, which occurred in the older versions when the AML-driven aircraft attempted a vertical or near vertical loop. Third, the requirements for a versatile generic, yet realistic, aircraft model were studied and implemented in the program. The report contains detailed tables which make the generic aircraft to be either a modern, high performance aircraft, an older high performance aircraft, or a previous generation jet fighter.

Burgin, George H.↗

Circadian countermeasures for shiftworkers during USMP-2: A report to mission management

People who must work at night experience a number of physiological and psychological difficulties. These include sleepiness and fatigue at work, poor daytime sleep, gastrointestinal distress, impaired concentration and performance, disturbed mood, and increased health complaints and risk of disease. These difficulties arise because nocturnal work and daytime sleep take place at inappropriate phases of the body's circadian rhythms. Intense artificial light can shift the phase of human circadian rhythms, and can thus be used to promote adaptation to shifted work schedules. The first attempts to investigate the efficacy of light treatment for MSFC POCC shiftworkers took place during USML-1 and ATLAS-2. The findings from these studies led to the development of a Circadian Countermeasures Program that was implemented during USMP-2. Light treatment and other circadian countermeasures were employed to promote adjustment to mission shiftwork in POCC cadre volunteers. Treatment protocols were designed and customized for each volunteer's work hours and personal preferences. Treatment protocols included some or all of the following: scheduled self-administration of intense light, scheduled avoidance or attenuation of sunlight at other times, and sleep schedules. Data from post-mission questionnaires indicated that volunteers found the program to be effective, convenient, and beneficial.

Stewart, Karen T.↗

The MHOST finite element program: 3-D inelastic analysis methods for hot section components. Volume 2: User's manual

The user options available for running the MHOST finite element analysis package is described. MHOST is a solid and structural analysis program based on the mixed finite element technology, and is specifically designed for 3-D inelastic analysis. A family of 2- and 3-D continuum elements along with beam and shell structural elements can be utilized, many options are available in the constitutive equation library, the solution algorithms and the analysis capabilities. The outline of solution algorithms is discussed along with the data input and output, analysis options including the user subroutines and the definition of the finite elements implemented in the program package.

Nakazawa, Shohei↗

Large space structure damping design

Several FORTRAN subroutines and programs were developed which compute complex eigenvalues of a damped system using different approaches, and which rescale mode shapes to unit generalized mass and make rigid bodies orthogonal to each other. An analytical proof of a Minimum Constrained Frequency Criterion (MCFC) for a single damper is presented. A method to minimize the effect of control spill-over for large space structures is proposed. The characteristic equation of an undamped system with a generalized control law is derived using reanalysis theory. This equation can be implemented in computer programs for efficient eigenvalue analysis or control quasi synthesis. Methods to control vibrations in large space structure are reviewed and analyzed. The resulting prototype, using electromagnetic actuator, is described.

Pilkey, W. D.↗

STARS: A general-purpose finite element computer program for analysis of engineering structures

STARS (Structural Analysis Routines) is primarily an interactive, graphics-oriented, finite-element computer program for analyzing the static, stability, free vibration, and dynamic responses of damped and undamped structures, including rotating systems. The element library consists of one-dimensional (1-D) line elements, two-dimensional (2-D) triangular and quadrilateral shell elements, and three-dimensional (3-D) tetrahedral and hexahedral solid elements. These elements enable the solution of structural problems that include truss, beam, space frame, plane, plate, shell, and solid structures, or any combination thereof. Zero, finite, and interdependent deflection boundary conditions can be implemented by the program. The associated dynamic response analysis capability provides for initial deformation and velocity inputs, whereas the transient excitation may be either forces or accelerations. An effective in-core or out-of-core solution strategy is automatically employed by the program, depending on the size of the problem. Data input may be at random within a data set, and the program offers certain automatic data-generation features. Input data are formatted as an optimal combination of free and fixed formats. Interactive graphics capabilities enable convenient display of nodal deformations, mode shapes, and element stresses.

Gupta, K. K.↗

Getting Involved with the Discovery Program

NASA's Discovery Program represents the implementation of NASA Administrator Daniel Goldin's vision of 'faster, better, cheaper' planetary missions; encompasses a series of low-cost solar system exploration missions intended to accomplish high quality, focused planetary science investigations using innovative, streamlined, and efficient approaches to assure the highest science value for the cost; and aims to enhance our understanding of the solar system by exploring the planets, their moons and other small bodies, either by traveling to them or remotely from the vicinity of Earth. The objectives of this program include the following: (1) Provide exciting and important scientific data to the global community; (2) Pursue new and innovative ways of doing business; (3) Encourage technological development by designing and testing new technologies and transferring them to the private sector; (4) Increase public awareness of, and appreciation for, solar system exploration through exciting education and public outreach activities; (5) Support national education initiatives through mission-specific programs; and (6) Ensure participation of small disadvantaged businesses, women-owned businesses, HBCUs, and other minority educational institutions in procurements.

Asplund, Shari↗

TOAD Editor

Transferable Output ASCII Data (TOAD) computer program (LAR-13755), implements format designed to facilitate transfer of data across communication networks and dissimilar host computer systems. Any data file conforming to TOAD format standard called TOAD file. TOAD Editor is interactive software tool for manipulating contents of TOAD files. Commonly used to extract filtered subsets of data for visualization of results of computation. Also offers such user-oriented features as on-line help, clear English error messages, startup file, macroinstructions defined by user, command history, user variables, UNDO features, and full complement of mathematical statistical, and conversion functions. Companion program, TOAD Gateway (LAR-14484), converts data files from variety of other file formats to that of TOAD. TOAD Editor written in FORTRAN 77.

Bingle, Bradford D.↗

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.↗

Space Station needs, attributes and architectural options, volume 2, book 3: Cost and programmatics

The cost and programmatic considerations which integrate mission requirements and architectural options into a cohesive system for exploitation of space opportunities within affordable limits are discussed. The mission requirements, baseline architecture, a top level baseline schedule, and acquisition costs are summarized. The work breakdown structure (WBS) used to structure the program, and the WBS dictionary are included. The costing approach used, including the operation of the primary costing tool, the SPACE cost model are described. The rationale for the choice of cost estimating relationships is given and costs at the module level are shown. Detailed costs at the subsystem level are shown. The baseline schedule and annual funding profiles are provided. Alternate schedules are developed to provide different funding profiles. Alternate funding sources are discussed and foreign and contractor participation is outlined. The results of the benefit analysis are given and the accrued benefits deriving from an implemented space station program are outlined.

Source record↗

Overview of environmental test plans for Space Station Freedom work package 4

The generation and distribution of electric power for Space Station Freedom (SSF) is critical to the station's success. Work Package 4 (WP-04) has the responsibility for the design, development, test, and delivery of the Electric Power System (EPS) for the SSF. During launch, assembly, and operation, the EPS will be subjected to various environments. A test and verification approach has been developed to assure that the EPS will function in these environments. An overview of that test program is presented with emphasis on environmental testing of hardware. Two key areas of the test program are highlighted in the overview. One area is the verification of the Solar Power Module (SPM) and associated cargo element hardware. This area includes detailing the plans for development and qualification testing of the SPM hardware. One series of tests, including modal and acoustic, has been completed on a development cargo element. Another area highlighted is the acceptance testing of high-power Orbital Replacement Units (ORU). The environmental test equipment plans are presented and reviewed in light of an aggressive production rate, which delivers ORU's to the WP-04 and other Space Station Work Packages. Through implementing the test program as outlined, the EPS hardware will be certified for flight and operation on the Space Station Freedom.

Peterson, Tom J.↗

Recertification analysis and inspection planning for environmental test facilities

Program development and implementation for recertification of pressure vessels used at NASA facilities are outlined, together with inspection procedures. The recertification is carried out in three phases: analysis, inspection planning, and long term inspection plans and management. A data base was developed for each piece of equipment and the associated performance parameters. Either documentation was obtained or NDT was performed on the vessels to confirm design and Code compliance. A Failure Modes and Effects Analysis technique was used to target recurring inspection items and guidelines were drawn up for inspections of parts and systems and intervals between inspections. The steps taken in establishing the program are considered applicable in both research and industrial situations.

Rebeck, K. J.↗

Verification of a Constraint Force Equation Methodology for Modeling Multi-Body Stage Separation

This paper discusses the verification of the Constraint Force Equation (CFE) methodology and its implementation in the Program to Optimize Simulated Trajectories II (POST2) for multibody separation problems using three specially designed test cases. The first test case involves two rigid bodies connected by a fixed joint; the second case involves two rigid bodies connected with a universal joint; and the third test case is that of Mach 7 separation of the Hyper-X vehicle. For the first two cases, the POST2/CFE solutions compared well with those obtained using industry standard benchmark codes, namely AUTOLEV and ADAMS. For the Hyper-X case, the POST2/CFE solutions were in reasonable agreement with the flight test data. The CFE implementation in POST2 facilitates the analysis and simulation of stage separation as an integral part of POST2 for seamless end-to-end simulations of launch vehicle trajectories.

Tartabini, Paul V.↗

Comprehensive analysis of helicopters with bearingless rotors

A modified Galerkin method is developed to analyze the dynamic problems of multiple-load-path bearingless rotor blades. The development and selection of functions are quite parallel to CAMRAD procedures, greatly facilitating the implementation of the method into the CAMRAD program. A software is developed implementing the modified Galerkin method to determine free vibration characteristics of multiple-load-path rotor blades undergoing coupled flapwise bending, chordwise bending, twisting, and extensional motions. Results are in the process of being obtained by debugging the software.

Murthy, V. R.↗

Eclipse-Free-Time Assessment Tool for IRIS

IRIS_EFT is a scientific simulation that can be used to perform an Eclipse-Free- Time (EFT) assessment of IRIS (Infrared Imaging Surveyor) mission orbits. EFT is defined to be those time intervals longer than one day during which the IRIS spacecraft is not in the Earth s shadow. Program IRIS_EFT implements a special perturbation of orbital motion to numerically integrate Cowell's form of the system of differential equations. Shadow conditions are predicted by embedding this integrator within Brent s method for finding the root of a nonlinear equation. The IRIS_EFT software models the effects of the following types of orbit perturbations on the long-term evolution and shadow characteristics of IRIS mission orbits. (1) Non-spherical Earth gravity, (2) Atmospheric drag, (3) Point-mass gravity of the Sun, and (4) Point-mass gravity of the Moon. The objective of this effort was to create an in-house computer program that would perform eclipse-free-time analysis. of candidate IRIS spacecraft mission orbits in an accurate and timely fashion. The software is a suite of Fortran subroutines and data files organized as a "computational" engine that is used to accurately predict the long-term orbit evolution of IRIS mission orbits while searching for Earth shadow conditions.

Eagle, David↗

Scaling Demand Flexibility: Building on 30 Years of Energy Efficiency Success

With electricity consumption across the United States (US) and Canada anticipated to grow, energy efficiency program administrators have a key role to play in helping to ensure energy affordability and reliability in support of the broader economic systems utilities and grid support. Connected, demand side load balancing solutions, such as load shifting heating, ventilation and air conditioning (HVAC) systems and managed charging for electric vehicles (EVs), can dynamically manage energy, allowing for more volumetric electricity consumption without incurring the expense of upgraded transmission and distribution capabilities. When combined, or aggregated, many small loads can be managed to have meaningful impact on energy demand on the grid. Utilities and their partners have an opportunity to leverage decades of experience and the infrastructure needed to assess, design, implement, and measure programs to scale up the adoption of equipment with built-in load flexibility capabilities. Current efforts among a wide variety of electricity system service providers, utilities, standards agencies, regulators, national labs and private industry stakeholders aim to identify common standards, metrics, and methodologies for valuing grid services offered by demand side equipment. By combining those efforts with decades of proven energy efficiency resources, utilities are poised to effectuate a scaling up of equipment with energy management capabilities installed in homes and businesses across the US and Canada. This paper will provide an overview of how utilities are approaching this era of load growth and new peak demands across the United States and Canada. It will highlight the specific strategies that program administrators are employing to advance market transformation for grid-enabled products and devices that have the greatest potential to reduce energy use and increase load flexibility.

Grant, Peter↗

Initial experience with distributing structural calculations among computers operating in parallel

An existing program is currently being adapted to perform finite element analysis by distributing substructures over a network of four Apple IIe microcomputers connected to a shared disk. In this network, one microcomputer controls the entire process while the others perform the analysis on each substructure in parallel. This substructure analysis is used in an iterative, fully stressed, structural resizing procedure. This procedure allows experimentatation with resizing in which all analyses are not completed during a single iteration. This research gives some insight on how to configure multidiscriplinary analysis and optimization procedures for decomposable engineering systems using either high performance engineering workstations or a parallel processor supercomputer. In addition, the operational experience gained facilitates the implementation of analysis programs on these new computers when they become available in an engineering environment.

Rogers, J. L., Jr.↗