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  • COMPUTER PROGRAMMING AND SOFTWARE  (295)
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  • 1
    Publication Date: 2004-12-04
    Description: Redundant search often makes Prolog programs inefficient. Prolog execution corresponds to a depth-first traversal of an AND/OR graph; often a large subgraph will be searched successfully, with failure resulting from a subsequent small one. It is shown how reordering of Prolog clauses and especially goals can prevent unnecessary search. The restrictions on reordering are characterized and how they may be detected is shown. A new system of calling modes for Prolog, geared to reordering, and a system for inferring them automatically are designed. An improved method for determining a good goal order for Prolog clauses is presented, and it is used as the basis for a reordering system, showing how it can be guided by information about modes and restrictions to generate reordered Prolog that behaves correctly.
    Keywords: COMPUTER PROGRAMMING AND SOFTWARE
    Type: Presentation Slides and Publications. NASA Review of ICLASS: Illinois Computer Laboratory for Aerospace Systems and Software; 41 p
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  • 2
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    Publication Date: 2011-08-19
    Description: An essential ingredient in scientific work is data. In disciplines such as Oceanography, data sources are many and volumes are formidable. The full value of large stores of data cannot be realized unless careful thought is given to data access. JPL has developed the Pilot Ocean Data System to investigate techniques for archiving and accessing ocean data obtained from space. These include efficient storage and rapid retrieval of satellite data, an easy-to-use user interface, and a variety of output products which, taken together, permit researchers to extract and use data rapidly and conveniently.
    Keywords: COMPUTER PROGRAMMING AND SOFTWARE
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  • 3
    Publication Date: 2011-08-19
    Description: Difficulties encountered in the modeling of fault-tolerant systems are discussed. The Hybrid Automated Reliability Predictor (HARP) approach to modeling fault-tolerant systems is described. The HARP is written in FORTRAN, consists of nearly 30,000 lines of codes and comments, and is based on behavioral decomposition. Using the behavioral decomposition, the dependability model is divided into fault-occurrence/repair and fault/error-handling models; the characteristics and combining of these two models are examined. Examples in which the HARP is applied to the modeling of some typical fault-tolerant systems, including a local-area network, two fault-tolerant computer systems, and a flight control system, are presented.
    Keywords: COMPUTER PROGRAMMING AND SOFTWARE
    Type: IEEE Transactions on Reliability (ISSN 0018-9529); R-36; 176-185
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  • 4
    Publication Date: 2011-08-19
    Description: The Common Data Format (CDF), a structure which provides true data independence for applications software and has been developed at the National Space Science Data Center, is discussed. The background to the CDF is reviewed, and the CDF is described. The conceptual organization of the CDF is discussed, and a sample CDF structure is shown and described. The implementation of CDF, its status, and its applications are examined.
    Keywords: COMPUTER PROGRAMMING AND SOFTWARE
    Type: EOS (ISSN 0096-3941); 68; 633-635
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  • 5
    Publication Date: 2011-08-19
    Description: The integration of CAD/CAM/mapping with image processing using geographic information systems (GISs) as the interface is examined. Particular emphasis is given to the development of software interfaces between JPL's Video Image Communication and Retrieval (VICAR)/Imaged Based Information System (IBIS) raster-based GIS and the CAD/CAM/mapping system. The design and functions of the VICAR and IBIS are described. Vector data capture and editing are studied. Various software programs for interfacing between the VICAR/IBIS and CAD/CAM/mapping are presented and analyzed.
    Keywords: COMPUTER PROGRAMMING AND SOFTWARE
    Type: Photogrammetric Engineering and Remote Sensing (ISSN 0099-1112); 53; 1391-139
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  • 6
    Publication Date: 2011-08-19
    Description: The FDDI Token Ring Protocol controls communication over fiber optic rings with transmission rates in the range of 100 megabits per second. It is intended to give guaranteed response to time-critical messages by using a 'timed token' protocol, in which noncritical messages may be transmitted only if recent movement of the token among stations has been sufficiently fast relative to a 'target' token rotation line (TTRT). In this paper, two important properties of the protocol are proved. The first is that the average token cycle time is bounded above by the TTRT, and the second is that the maximum token cycle time is at most twice the TTRT. Each property is treated first under the assumption that all overheads are negligible, and second with certain sources of overhead taken into account explicitly. It is found that the proposed standard protocol can be improved for situations of practical interest by a slight modification.
    Keywords: COMPUTER PROGRAMMING AND SOFTWARE
    Type: IEEE Transactions on Software Engineering (ISSN 0098-5589); SE-13; 376-385
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  • 7
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    In:  CASI
    Publication Date: 2013-08-31
    Description: The prototype demonstrates the feasibility of using Ada for expert systems and the implementation of an expert-friendly interface which supports knowledge entry. In the Ford LISP-Ada Connection (FLAC) system LISP and Ada are used in ways which complement their respective capabilities. Future investigation will concentrate on the enhancement of the expert knowledge entry/debugging interface and on the issues associated with multitasking and real-time expert systems implementation in Ada.
    Keywords: COMPUTER PROGRAMMING AND SOFTWARE
    Type: NASA, Goddard Space Flight Center, Proceedings of 1987 Goddard Conference on Space Applications of Artificial Intelligence (AI) and Robotics; 14 p
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  • 8
    Publication Date: 2013-08-31
    Description: Two expert systems were written in OPS5 by the expert, a Ph.D. astronomer with no prior experience in artificial intelligence or expert systems, without the use of a knowledge engineer. The first system was built from scratch and uses 146 rules to check for duplication of scientific information within a pool of prospective observations. The second system was grafted onto another expert system and uses 149 additional rules to estimate the spacecraft and ground resources consumed by a set of prospective observations. The small vocabulary, the IF this occurs THEN do that logical structure of OPS5, and the ability to follow program execution allowed the expert to design and implement these systems with only the data structures and rules of another OPS5 system as an example. The modularity of the rules in OPS5 allowed the second system to modify the rulebase of the system onto which it was grafted without changing the code or the operation of that system. These experiences show that experts are able to develop their own expert systems due to the ease of programming and code reusability in OPS5.
    Keywords: COMPUTER PROGRAMMING AND SOFTWARE
    Type: NASA, Goddard Space Flight Center, Proceedings of 1987 Goddard Conference on Space Applications of Artificial Intelligence (AI) and Robotics; 14 p
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  • 9
    Publication Date: 2013-08-31
    Description: The proposal selection process for the Hubble Space Telescope is assisted by a robust and easy to use query program (TACOS). The system parses an English subset language sentence regardless of the order of the keyword phases, allowing the user a greater flexibility than a standard command query language. Capabilities for macro and procedure definition are also integrated. The system was designed for flexibility in both use and maintenance. In addition, TACOS can be applied to any knowledge domain that can be expressed in terms of a single reaction. The system was implemented mostly in Common LISP. The TACOS design is described in detail, with particular attention given to the implementation methods of sentence processing.
    Keywords: COMPUTER PROGRAMMING AND SOFTWARE
    Type: NASA, Goddard Space Flight Center, Proceedings of 1987 Goddard Conference on SpaceApplications o f Artificial Intelligence (AI) and Robotics; 17 p
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  • 10
    Publication Date: 2013-08-31
    Description: The principle focus of one of the RICIS (Research Institute for Computing and Information Systems) components is computer systems and software engineering in-the-large of the lifecycle of large, complex, distributed systems which: (1) evolve incrementally over a long time; (2) contain non-stop components; and (3) must simultaneously satisfy a prioritized balance of mission and safety critical requirements at run time. This focus is extremely important because of the contribution of the scaling direction problem to the current software crisis. The Computer Systems and Software Engineering (CSSE) component addresses the lifestyle issues of three environments: host, integration, and target.
    Keywords: COMPUTER PROGRAMMING AND SOFTWARE
    Type: RICIS 1987 Symposium. Executive Summary 5 p(SEE N91-18616 10-61); RICIS 1987 Symposium
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  • 11
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    In:  CASI
    Publication Date: 2013-08-31
    Description: A cooperative program was initiated by JSC with the University of Houston - Clear Lake to support research in computing and information systems. The objective of this program is to provide continuing long-term research in support of the numerous mission and mission-related endeavors of NASA/JSC. The Research Institute for Computing and Information Systems (RICIS) concept is presented in form of viewgraphs. History of RICIS, its organization, and research status are discussed.
    Keywords: COMPUTER PROGRAMMING AND SOFTWARE
    Type: Houston Univ., RICIS 1987 Symposium. Executive Summary; 35 p
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  • 12
    Publication Date: 2013-08-31
    Description: Quality of software not only is vital to the successful operation of the space station, it is also an important factor in establishing testing requirements, time needed for software verification and integration as well as launching schedules for the space station. Defense of management decisions can be greatly strengthened by combining engineering judgments with statistical analysis. Unlike hardware, software has the characteristics of no wearout and costly redundancies, thus making traditional statistical analysis not suitable in evaluating reliability of software. A statistical model was developed to provide a representation of the number as well as types of failures occur during software testing and verification. From this model, quantitative measure of software reliability based on failure history during testing are derived. Criteria to terminate testing based on reliability objectives and methods to estimate the expected number of fixings required are also presented.
    Keywords: COMPUTER PROGRAMMING AND SOFTWARE
    Type: NASA. Johnson Space Center, NASA(ASEE Summer Faculty Fellowship Program, 1987, Volume 2; 20 p
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  • 13
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    In:  CASI
    Publication Date: 2013-08-31
    Description: The ability to determine the contents of a scene by a machine has obvious applications. There are reasons for seeking horizontal, vertical and diagonal line segments of varying lengths in order to interpret the content of a scene. Such line segments aid in determining edges that determine the boundaries of objects within the scene. Algorithms for each of the above as well as for data compacting are presented.
    Keywords: COMPUTER PROGRAMMING AND SOFTWARE
    Type: NASA. Johnson Space Center, NASA(ASEE Summer Faculty Fellowship Program, 1987, Volume 1; 16 p
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  • 14
    Publication Date: 2013-08-31
    Description: Various computer programs based upon the SIMPLE or SIMPLER algorithm were studied and compared for numerical accuracy, efficiency, and grid dependency. Four two-dimensional and one three-dimensional code originally developed by a number of research groups were considered. In general, the accuracy and computational efficieny of these TEACH type programs were improved by modifying the differencing schemes and their solvers. A brief description of each program is given. Error reduction, spline flux and second upwind differencing programs are covered.
    Keywords: COMPUTER PROGRAMMING AND SOFTWARE
    Type: NASA, Lewis Research Center, Turbine Engine Hot Section Technology, 1987; p 129-130
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  • 15
    Publication Date: 2013-08-31
    Description: A large scale, general purpose finite element computer program, ANSYS, developed and marketed by Swanson Analysis Systems, Inc. is discussed. ANSYS was perhaps the first commercially available program to offer truly interactive finite element model generation. ANSYS's purpose is for solid modeling. This application is briefly discussed and illustrated.
    Keywords: COMPUTER PROGRAMMING AND SOFTWARE
    Type: Rensselaer Polytechnic Inst., Workshop on the Integration of Finite Element Modeling with Geometric Modeling; 17 p
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  • 16
    Publication Date: 2013-08-31
    Description: A framework is presented for developing computationally unified numerical algorithms for solving nonlinear equations that arise in modeling various problems in mathematical physics. The concept of computational unification is an attempt to encompass efficient solution procedures for computing various nonlinear phenomena that may occur in a given problem. For example, in Computational Fluid Dynamics (CFD), a unified algorithm will be one that allows for solutions to subsonic (elliptic), transonic (mixed elliptic-hyperbolic), and supersonic (hyperbolic) flows for both steady and unsteady problems. The objectives are: development of superior unified algorithms emphasizing accuracy and efficiency aspects; development of codes based on selected algorithms leading to validation; application of mature codes to realistic problems; and extension/application of CFD-based algorithms to problems in other areas of mathematical physics. The ultimate objective is to achieve integration of multidisciplinary technologies to enhance synergism in the design process through computational simulation. Specific unified algorithms for a hierarchy of gas dynamics equations and their applications to two other areas: electromagnetic scattering, and laser-materials interaction accounting for melting.
    Keywords: COMPUTER PROGRAMMING AND SOFTWARE
    Type: NASA. Ames Research Center, Supercomputing in Aerospace; p 87-107
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  • 17
    Publication Date: 2013-08-31
    Description: Turbo Prolog is a recently available, compiled version of the programming language Prolog. Turbo Prolog is designed to provide not only a Prolog compiler, but also a program development environment for the IBM Personal Computer family. An evaluation of Turbo Prolog was made, comparing its features to other versions of Prolog and to the community of languages commonly used in artificial intelligence (AI) research and development. Three programs were employed to determine the execution speed of Turbo Prolog applied to various problems. The results of this evaluation demonstrated that Turbo Prolog can perform much better than many commonly employed AI languages for numerically intensive problems and can equal the speed of development languages such as OPS5+ and CLIPS, running on the IBM PC. Applications for which Turbo Prolog is best suited include those which (1) lend themselves naturally to backward-chaining approaches, (2) require extensive use of mathematics, (3) contain few rules, (4) seek to make use of the window/color graphics capabilities of the IBM PC, and (5) require linkage to programs in other languages to form a complete executable image.
    Keywords: COMPUTER PROGRAMMING AND SOFTWARE
    Type: NASA. Lyndon B.; NASA. Lyndon B. John
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  • 18
    Publication Date: 2013-08-31
    Description: Dynamic model verification is the process whereby an analytical model of a dynamic system is compared with experimental data, and then qualified for future use in predicting system response in a different dynamic environment. There are various ways to conduct model verification. The approach adopted in MOVER II employs Bayesian statistical parameter estimation. Unlike curve fitting whose objective is to minimize the difference between some analytical function and a given quantity of test data (or curve), Bayesian estimation attempts also to minimize the difference between the parameter values of that function (the model) and their initial estimates, in a least squares sense. The objectives of dynamic model verification, therefore, are to produce a model which: (1) is in agreement with test data, (2) will assist in the interpretation of test data, (3) can be used to help verify a design, (4) will reliably predict performance, and (5) in the case of space structures, facilitate dynamic control.
    Keywords: COMPUTER PROGRAMMING AND SOFTWARE
    Type: NASA. Marshall Space Flight Center Structural Dynamics and Control Interaction of Flexible Structures; p 199-214
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  • 19
    Publication Date: 2013-08-31
    Description: A multiflexible body dynamics code intended for fast turnaround control design trades is described. Nonlinear rigid body dynamics and linearized flexible dynamics combine to provide efficient solution of the equations of motion. Comparison with results from the DISCOS code provide verification of accuracy.
    Keywords: COMPUTER PROGRAMMING AND SOFTWARE
    Type: NASA. Marshall Space Flight Center Structural Dynamics and Control Interaction of Flexible Structures; p 979-998
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  • 20
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    Publication Date: 2013-08-31
    Description: Some important aspects of design modeling for shape optimization are discussed for both stamped sheet metal components and cast solid components. For stamped components the basis for the modeling approach is a boundary design function. Design parameters control the shape of 2-D regions. For more complex, folded plate components, the 2-D regions can be assembled using translation and rotation operations. The analysis model is automatically created using a mesh generation procedure requiring only boundary data. For less complex solid components, it was found that this approach is not suitable. For these structures, the finite element models are typically created using very sophisticated graphical modeling systems. A new approach which overlays a parameterized surface design model on an existing analysis model is described. To summarize, the future needs for solid shape design is described in terms of an extension of the previously described 2-D capability.
    Keywords: COMPUTER PROGRAMMING AND SOFTWARE
    Type: Rensselaer Polytechnic Inst., Workshop on the Integration of Finite Element Modeling with Geometric Modeling; 6 p
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  • 21
    Publication Date: 2013-08-31
    Description: The octree technique is developed into the finite octree, and an overview is given. Modeler requirements are given. The octree discretization is discussed along with geometric communication operators. Geometric communication operators returning topological associativity and geometric communication operators returning spatial data are also discussed and illustrated. The advantages are given of the boundary representation and of geometric communication operators. The implementation plays an important role in the integration with a variety of geometric modelers. The capabilities of closed loop processes within a complete finite element system are presented.
    Keywords: COMPUTER PROGRAMMING AND SOFTWARE
    Type: Workshop on the Integration of Finite Element Modeling with Geometric Modeling; 26 p
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  • 22
    Publication Date: 2013-08-31
    Description: The structure to a geometry based finite element preprocessing system is presented. The key features of the system are the use of geometric operators to support all geometric calculations required for analysis model generation, and the use of a hierarchic boundary based data structure for the major data sets within the system. The approach presented can support the finite element modeling procedures used today as well as the fully automated procedures under development.
    Keywords: COMPUTER PROGRAMMING AND SOFTWARE
    Type: Workshop on the Integration of Finite Element Modeling with Geometric Modeling; 24 p
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  • 23
    Publication Date: 2013-08-31
    Description: This paper describes the use of computer graphic simulation techniques to resolve critical design and operational issues for robotic systems. Use of this technology will result in greatly improved systems and reduced development costs. The major design issues in developing effective robotic systems are discussed and the use of ROBOSIM, a NASA developed simulation tool, to address these issues is presented. Three representative simulation case studies are reviewed: off-line programming of the robotic welding development cell for the Space Shuttle Main Engine (SSME); the integration of a sensor to control the robot used for removing the Thermal Protection System (TPS) from the Solid Rocket Booster (SRB); and the development of a teleoperator/robot mechanism for the Orbital Maneuvering Vehicle (OMV).
    Keywords: COMPUTER PROGRAMMING AND SOFTWARE
    Type: NASA. Lyndon B. Johnson Space Center, Houston, Texas. First Annual Workshop on Space Operations Automation and Robotics (SOAR 87); p 501-511
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  • 24
    Publication Date: 2013-08-31
    Description: Part 1 presented an overview of the unified approach to manufacturing software. The specific characteristics of the approach that allow it to realize the goals of reduced cost, increased reliability and increased flexibility are considered. Why the blending of a components view, distributed languages, generics and formal models is important, why each individual part of this approach is essential, and why each component will typically have each of these parts are examined. An example of a specification for a real material handling system is presented using the approach and compared with the standard interface specification given by the manufacturer. Use of the component in a distributed manufacturing system is then compared with use of the traditional specification with a more traditional approach to designing the system. An overview is also provided of the underlying mechanisms used for implementing distributed manufacturing systems using the unified software/hardware component approach.
    Keywords: COMPUTER PROGRAMMING AND SOFTWARE
    Type: NASA. Lyndon B. Johnson Space Center, Houston, Texas, First Annual Workshop on Space Operations Automation and Robotics (SOAR 87); p 399-403
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  • 25
    Publication Date: 2013-08-31
    Description: For several years, a broad, unified approach to programming manufacturing cells, factory floors, and other manufacturing systems has been developed. It is based on a blending of distributed Ada, software components, generics and formal models. Among other things the machines and devices which make up the components, and the entire manufacturing cell is viewed as an assembly of software components. The purpose of this project is to reduce cost, increase the reliability and increase the flexibility of manufacturing software. An overview is given of the approach and an experimental generic factory floor controller that was developed using the approach is described. The controller is generic in the sense that it can control any one of a large class of factory floors making an arbitrary mix of parts.
    Keywords: COMPUTER PROGRAMMING AND SOFTWARE
    Type: NASA. Lyndon B. Johnson Space Center, Houston, Texas, First Annual Workshop on Space Operations Automation and Robotics (SOAR 87); p 397-398
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  • 26
    Publication Date: 2013-08-31
    Description: The conventional control and monitor software currently used by the Space Center for Space Shuttle processing has many limitations such as high maintenance costs, limited diagnostic capabilities and simulation support. These limitations have caused the development of a knowledge based (or model based) shell to generically control and monitor electro-mechanical systems. The knowledge base describes the system's structure and function and is used by a software shell to do real time constraints checking, low level control of components, diagnosis of detected faults, sensor validation, automatic generation of schematic diagrams and automatic recovery from failures. This approach is more versatile and more powerful than the conventional hard coded approach and offers many advantages over it, although, for systems which require high speed reaction times or aren't well understood, knowledge based control and monitor systems may not be appropriate.
    Keywords: COMPUTER PROGRAMMING AND SOFTWARE
    Type: NASA. Lyndon B. Johnson Space Center, Houston, Texas, First Annual Workshop on Space Operations Automation and Robotics (SOAR 87); p 355-360
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  • 27
    Publication Date: 2013-08-31
    Description: SWAN is an expert system and natural language interface for assessing the war fighting capability of Air Force units in Europe. The expert system is an object oriented knowledge based simulation with an alternate worlds facility for performing what-if excursions. Responses from the system take the form of generated text, tables, or graphs. The natural language interface is an expert system in its own right, with a knowledge base and rules which understand how to access external databases, models, or expert systems. The distinguishing feature of the Air Force expert system is its use of meta-knowledge to generate explanations in the frame and procedure based environment.
    Keywords: COMPUTER PROGRAMMING AND SOFTWARE
    Type: NASA. Lyndon B. Johnson Space Center, Houston, Texas, First Annual Workshop on Space Operations Automation and Robotics (SOAR 87); p 341-348
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  • 28
    Publication Date: 2013-08-31
    Description: Constraints are used in the CAMPS knowledge based planning system to represent those propositions that must be true for a plan to be acceptable. CAMPS introduces the make-mode for interpreting a constraint. Given an unsatisfied constraint, make evaluation mode suggests planning actions which, if taken, would result in a modified plan in which the constraint in question may be satisfied. These suggested planning actions, termed delta-tuples, are the raw material of intelligent plan repair. They are used both in debugging an almost-right plan and in replanning due to changing situations. Given a defective plan in which some set of constraints are violated, a problem solving strategy selects one or more constraints as a focus of attention. These selected constraints are evaluated in the make-mode to produce delta-tuples. The problem solving strategy then reviews the delta-tuples according to its application and problem-specific criteria to find the most acceptable change in terms of success likelihood and plan disruption. Finally, the problem solving strategy makes the suggested alteration to the plan and then rechecks constraints to find any unexpected consequences.
    Keywords: COMPUTER PROGRAMMING AND SOFTWARE
    Type: NASA. Lyndon B. Johnson Space Center, Houston, Texas, First Annual Workshop on Space Operations Automation and Robotics (SOAR 87); p 307-313
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  • 29
    Publication Date: 2013-08-31
    Description: The Space Shuttle community is currently developing a number of knowledge-based tools, primarily expert systems, to support Space Shuttle operations. It is proposed that anticipating and responding to the requirements of the operations environment will contribute to a rapid and smooth transition of expert systems from development to operations, and that the requirements for verification are critical to this transition. The paper identifies the requirements of expert systems to be used for flight planning and support and compares them to those of existing procedural software used for flight planning and support. It then explores software engineering concepts and methodology that can be used to satisfy these requirements, to aid the transition from development to operations and to support the operations environment during the lifetime of expert systems. Many of these are similar to those used for procedural hardware.
    Keywords: COMPUTER PROGRAMMING AND SOFTWARE
    Type: NASA. Lyndon B. Johnson Space Center, Houston, Texas, First Annual Workshop on Space Operations Automation and Robotics (SOAR 87); p 203-207
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  • 30
    Publication Date: 2013-08-31
    Description: The IDEAL (Integrated Design and Engineering Analysis Languages) modeling methodology has been formulated and applied over a five-year period. It has proven to be a unique, integrated approach utilizing a top-down, structured technique to define and document the system of interest; a knowledge engineering technique to collect and organize system descriptive information; a rapid prototyping technique to perform preliminary system performance analysis; and a sophisticated simulation technique to perform in-depth system performance analysis.
    Keywords: COMPUTER PROGRAMMING AND SOFTWARE
    Type: NASA. Lyndon B. Johnson Space Center, Houston, Texas, First Annual Workshop on Space Operations Automation and Robotics (SOAR 87); p 153-158
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  • 31
    Publication Date: 2013-08-31
    Description: Where the Knowledge Based Software Assistant (KBSA) is now, four years after the initial report, is discussed. Also described is what the Rome Air Development Center expects at the end of the first contract iteration. What the second and third contract iterations will look like are characterized.
    Keywords: COMPUTER PROGRAMMING AND SOFTWARE
    Type: NASA. Lyndon B. Johnson Space Center, Houston, Texas, First Annual Workshop on Space Operations Automation and Robotics (SOAR 87); p 45-52
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  • 32
    Publication Date: 2013-08-31
    Description: The generation of a set of tools for software lifecycle is a recurring theme in the software engineering literature. The development of such tools and their integration into a software development environment is a difficult task because of the magnitude (number of variables) and the complexity (combinatorics) of the software lifecycle process. An initial development of a global approach was initiated in 1982 as the Software Development Workbench (SDW). Continuing efforts focus on tool development, tool integration, human interfacing, data dictionaries, and testing algorithms. Current efforts are emphasizing natural language interfaces, expert system software development associates and distributed environments with Ada as the target language. The current implementation of the SDW is on a VAX-11/780. Other software development tools are being networked through engineering workstations.
    Keywords: COMPUTER PROGRAMMING AND SOFTWARE
    Type: NASA. Lyndon B. Johnson Space Center, Houston, Texas, First Annual Workshop on Space Operations Automation and Robotics (SOAR 87); p 31-38
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  • 33
    Publication Date: 2013-08-31
    Description: An overview is presented of the Automated Software Development Workstation Project, an effort to explore knowledge-based approaches to increasing software productivity. The project focuses on applying the concept of domain specific automatic programming systems (D-SAPSs) to application domains at NASA's Johnson Space Center. A version of a D-SAPS developed in Phase 1 of the project for the domain of space station momentum management is described. How problems encountered during its implementation led researchers to concentrate on simplifying the process of building and extending such systems is discussed. Researchers propose to do this by attacking three observed bottlenecks in the D-SAPS development process through the increased automation of the acquisition of programming knowledge and the use of an object oriented development methodology at all stages of the program design. How these ideas are being implemented in the Bauhaus, a prototype workstation for D-SAPS development is discussed.
    Keywords: COMPUTER PROGRAMMING AND SOFTWARE
    Type: NASA. Lyndon B. Johnson Space Center, Houston, Texas, First Annual Workshop on Space Operations Automation and Robotics (SOAR 87); p 39-44
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  • 34
    Publication Date: 2013-08-31
    Description: Control of on-orbit operation of a spacecraft requires retention and application of special purpose, often unique, knowledge of equipment and procedures. Real-time distributed expert systems (RTDES) permit a modular approach to a complex application such as on-orbit spacecraft support. One aspect of a human-machine system that lends itself to the application of RTDES is the function of satellite/mission controllers - the next logical step toward the creation of truly autonomous spacecraft systems. This system application is described.
    Keywords: COMPUTER PROGRAMMING AND SOFTWARE
    Type: NASA. Marshall Space Flight Center, Third Conference on Artificial Intelligence for Space Applications, Part 1; p 439-443
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  • 35
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    In:  CASI
    Publication Date: 2013-08-31
    Description: For the evolving discipline of programming, acquisition of programming knowledge is a difficult issue. Common knowledge results from the acceptance of proven techniques based on results of formal inquiries into the nature of the programming process. This is a rather slow process. In addition, the vast body of common knowledge needs to be explicated to a low enough level of details for it to be represented in the machine processable form. It is felt that this is an impediment to the progress of automatic programming. The importance of formal approaches cannot be overstated since their contributions lead to quantum leaps in the state of the art.
    Keywords: COMPUTER PROGRAMMING AND SOFTWARE
    Type: NASA. Marshall Space Flight Center, Third Conference on Artificial Intelligence for Space Applications, Part 1; p 427-431
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  • 36
    Publication Date: 2013-08-31
    Description: An overview of the knowledge acquisition component of the Bauhaus, a prototype computer aided software engineering (CASE) workstation for the development of domain-specific automatic programming systems (D-SAPS) is given. D-SAPS use domain knowledge in the refinement of a description of an application program into a compilable implementation. The approach to the construction of D-SAPS was to automate the process of refining a description of a program, expressed in an object-oriented domain language, into a configuration of software parts that implement the behavior of the domain objects.
    Keywords: COMPUTER PROGRAMMING AND SOFTWARE
    Type: NASA. Marshall Space Flight Center, Third Conference on Artificial Intelligence for Space Applications, Part 1; p 423-424
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  • 37
    Publication Date: 2013-08-31
    Description: Results of preliminary research on the design of a knowledge based fault diagnosis system for use with on-orbit spacecraft such as the Hubble Space Telescope are presented. A candidate data structure and associated search algorithm from which the knowledge based system can evolve is discussed. This algorithmic approach will then be examined in view of its inability to diagnose certain common faults. From that critique, a design for the corresponding knowledge based system will be given.
    Keywords: COMPUTER PROGRAMMING AND SOFTWARE
    Type: NASA. Marshall Space Flight Center, Third Conference on Artificial Intelligence for Space Applications, Part 1; p 403-407
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  • 38
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    In:  CASI
    Publication Date: 2013-08-31
    Description: Applications of linguistic principles to potential problems of human and machine communication in space settings are discussed. Variations in language among speakers of different backgrounds and change in language forms resulting from new experiences or reduced contact with other groups need to be considered in the design of intelligent machine systems.
    Keywords: COMPUTER PROGRAMMING AND SOFTWARE
    Type: NASA. Marshall Space Flight Center, Third Conference on Artificial Intelligence for Space Applications, Part 1; p 333-337
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  • 39
    Publication Date: 2013-08-31
    Description: Recently the artificial intelligence community has turned its attention to the process of discovery and found that the history of science is a fertile source for what Darden has called compiled hindsight. Such hindsight generates weak heuristics for discovery that do not guarantee that discoveries will be made but do have proven worth in leading to discoveries. Triangulation is one such heuristic that is grounded in historical hindsight. This heuristic is explored within the general framework of the BACON, GLAUBER, STAHL, DALTON, and SUTTON programs. In triangulation different bases of information are compared in an effort to identify gaps between the bases. Thus, assuming that the bases of information are relevantly related, the gaps that are identified should be good locations for discovery and robust analysis.
    Keywords: COMPUTER PROGRAMMING AND SOFTWARE
    Type: NASA. Marshall Space Flight Center, Third Conference on Artificial Intelligence for Space Applications, Part 1; p 285-289
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  • 40
    Publication Date: 2013-08-31
    Description: It is demonstrated that when iterative-deepening A asterisk (IDA asterisk) is applied to one type of resource allocation problem, it uses far less storage than A asterisk, but opens far more nodes and thus has unacceptable time complexity. This is shown to be due, at least in part, to the low-valued effective branching factor that is a characteristic of problems with real-valued cost functions. The semi-optimal, epsilon-admissible IDA asterisk sub epsilon search algorithm that the authors described was shown to open fewer nodes than both A asterisk and IDA asterisk with storage complexity proportional to the depth of the search tree.
    Keywords: COMPUTER PROGRAMMING AND SOFTWARE
    Type: NASA. Marshall Space Flight Center, Third Conference on Artificial Intelligence for Space Applications, Part 1; p 273-277
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  • 41
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    In:  CASI
    Publication Date: 2013-08-31
    Description: An architecture for a knowledge-based simulator is described. The task of scheduling represents an area in which such a tool might be applied. More specifically, scheduling for crew and ground support activities for the shuttle and space station would benefit from the application of knowledge-based simulation. The knowledge-based simulator would allow the crew and support personnel to schedule and reschedule activities in a timely and flexible manner in order to examine and test possible plans.
    Keywords: COMPUTER PROGRAMMING AND SOFTWARE
    Type: NASA. Marshall Space Flight Center, Third Conference on Artificial Intelligence for Space Applications, Part 1; p 249-253
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  • 42
    Publication Date: 2013-08-31
    Description: The development of a simulation assistant for modeling discrete event processes is presented. Included are an overview of the system, a description of the simulation generators, and a sample process generated using the simulation assistant.
    Keywords: COMPUTER PROGRAMMING AND SOFTWARE
    Type: NASA. Marshall Space Flight Center, Third Conference on Artificial Intelligence for Space Applications, Part 1; p 243-247
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  • 43
    Publication Date: 2013-08-31
    Description: A methodology for automatic mathematical modeling is described. The major objective is to create a very friendly environment for engineers to design, maintain and verify their model and also automatically convert the mathematical model into FORTRAN code for conventional computation. A demonstration program was designed for modeling the Space Shuttle Main Engine simulation mathematical model called Propulsion System Automatic Modeling (PSAM). PSAM provides a very friendly and well organized environment for engineers to build a knowledge base for base equations and general information. PSAM contains an initial set of component process elements for the Space Shuttle Main Engine simulation and a questionnaire that allows the engineer to answer a set of questions to specify a particular model. PSAM is then able to automatically generate the model and the FORTRAN code. A future goal is to download the FORTRAN code to the VAX/VMS system for conventional computation.
    Keywords: COMPUTER PROGRAMMING AND SOFTWARE
    Type: Third Conference on Artificial Intelligence for Space Applications, Part 1; p 233-242
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  • 44
    Publication Date: 2013-08-31
    Description: A method is proposed whereby the underlying domain knowledge is represented such that illustrative examples may be generated on demand. This method has the advantage that the generated example can follow changes in the domain in addition to allowing automatic customization of the example to the individual.
    Keywords: COMPUTER PROGRAMMING AND SOFTWARE
    Type: Third Conference on Artificial Intelligence for Space Applications, Part 1; p 221-226
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  • 45
    Publication Date: 2013-08-31
    Description: Progress is reported on the development of SCOTTY, an expert knowledge-based system to automate the analysis procedure following test firings of the Space Shuttle Main Engine (SSME). The integration of a large-scale relational data base system, a computer graphics interface for experts and end-user engineers, potential extension of the system to flight engines, application of the system for training of newly-hired engineers, technology transfer to other engines, and the essential qualities of good software engineering practices for building expert knowledge-based systems are among the topics discussed.
    Keywords: COMPUTER PROGRAMMING AND SOFTWARE
    Type: NASA. Marshall Space Flight Center, Third Conference on Artificial Intelligence for Space Applications, Part 1; p 203-212
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  • 46
    Publication Date: 2013-08-31
    Description: A Failure Modes and Effects Analysis workstation (FMESassist) was designed for use during the development of the space station. It assists engineers in the complex task of tracking failures and their effects on the system. Engineers experience increased productivity through reduced clerical loads, reduced data inconsistency, and significantly reduced analysis time. System developments benefit from a more thorough analysis than was available using previous methods.
    Keywords: COMPUTER PROGRAMMING AND SOFTWARE
    Type: NASA. Marshall Space Flight Center, Third Conference on Artificial Intelligence for Space Applications, Part 1; p 187-191
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  • 47
    Publication Date: 2013-08-31
    Description: The C Language Integrated Production System (CLIPS) is a forward chaining rule-based language. The requirements necessary for an expert system tool which is used for development, delivery, and training are examined. Because of its high portability, low cost, and ease of integration with external systems, CLIPS has great potential as an expert system tool for delivery and training. In addition, its representation flexibility, debugging aids, and performance, along with its other strengths, make it a viable alternative for expert system development.
    Keywords: COMPUTER PROGRAMMING AND SOFTWARE
    Type: NASA. Marshall Space Flight Center, Third Conference on Artificial Intelligence for Space Applications, Part 1; p 53-57
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  • 48
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    In:  CASI
    Publication Date: 2013-08-31
    Description: CLIPS is a language for writing expert systems applications on a personal or small computer. Here, the CLIPS programming language is described and compared to three other artificial intelligence (AI) languages (LISP, Prolog, and OPS5) with regard to the processing they provide for the implementation of a knowledge based system (KBS). A discussion is given on how CLIPS would be used in a control system.
    Keywords: COMPUTER PROGRAMMING AND SOFTWARE
    Type: NASA. Marshall Space Flight Center, Third Conference on Artificial Intelligence for Space Applications, Part 1; p 33-40
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  • 49
    Publication Date: 2013-08-31
    Description: The implementation of an inference engine for embedded diagnostic systems is described. The system consists of two distinct parts. The first is an off-line compiler which accepts a propositional logical statement of the relationship between facts and conclusions and produces data structures required by the on-line inference engine. The second part consists of the inference engine and interface routines which accept assertions of fact and return the conclusions which necessarily follow. Given a set of assertions, it will generate exactly the conclusions which logically follow. At the same time, it will detect any inconsistencies which may propagate from an inconsistent set of assertions or a poorly formulated set of rules. The memory requirements are fixed and the worst case execution times are bounded at compile time. The data structures and inference algorithms are very simple and well understood. The data structures and algorithms are described in detail. The system has been implemented on Lisp, Pascal, and Modula-2.
    Keywords: COMPUTER PROGRAMMING AND SOFTWARE
    Type: NASA. Marshall Space Flight Center, Third Conference on Artificial Intelligence for Space Applications, Part 1; p 47-51
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  • 50
    Publication Date: 2013-08-31
    Description: The Diagnostic System Development Shell (DSDS), an expert system development shell for diagnostic systems, is described. The major objective of building the DSDS is to create a very easy to use and friendly environment for knowledge engineers and end-users. The DSDS is written in OPS5 and CommonLisp. It runs on a VAX/VMS system. A set of domain independent, generalized rules is built in the DSDS, so the users need not be concerned about building the rules. The facts are explicitly represented in a unified format. A powerful check facility which helps the user to check the errors in the created knowledge bases is provided. A judgement facility and other useful facilities are also available. A diagnostic system based on the DSDS system is question driven and can call or be called by other knowledge based systems written in OPS5 and CommonLisp. A prototype diagnostic system for diagnosing a Philips constant potential X-ray system has been built using the DSDS.
    Keywords: COMPUTER PROGRAMMING AND SOFTWARE
    Type: NASA. Marshall Space Flight Center, Third Conference on Artificial Intelligence for Space Applications, Part 1; p 41-45
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  • 51
    Publication Date: 2013-08-31
    Description: A basic paradigm that allows representation of physical systems with a focus on context and time is presented. Paragon provides the capability to quickly capture an expert's knowledge in a cognitively resonant manner. From that description, Paragon creates a simulation model in LISP, which when executed, verifies that the domain expert did not make any mistakes. The Achille's heel of rule-based systems has been the lack of a systematic methodology for testing, and Paragon's developers are certain that the model-based approach overcomes that problem. The reason this testing is now possible is that software, which is very difficult to test, has in essence been transformed into hardware.
    Keywords: COMPUTER PROGRAMMING AND SOFTWARE
    Type: NASA. Marshall Space Flight Center, Third Conference on Artificial Intelligence for Space Applications, Part 1; p 15-19
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  • 52
    Publication Date: 2013-08-31
    Description: The techniques described provide an effective tool which knowledge engineers and domain experts can utilize to help in evaluating and refining rules. These techniques have been used successfully as learning mechanisms in a prototype adaptive diagnostic expert system and are applicable to other types of expert systems. The degree to which they constitute complete evaluation/refinement of an expert system depends on the thoroughness of their use.
    Keywords: COMPUTER PROGRAMMING AND SOFTWARE
    Type: NASA. Marshall Space Flight Center, Third Conference on Artificial Intelligence for Space Applications, Part 1; p 9-13
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  • 53
    Publication Date: 2013-08-31
    Description: Verification and validation of expert systems is very important for the future success of this technology. Software will never be used in non-trivial applications unless the program developers can assure both users and managers that the software is reliable and generally free from error. Therefore, verification and validation of expert systems must be done. The primary hindrance to effective verification and validation is the use of methodologies which do not produce testable requirements. An extension of the flight technique panels used in previous NASA programs should provide both documented requirements and very high levels of verification for expert systems.
    Keywords: COMPUTER PROGRAMMING AND SOFTWARE
    Type: NASA. Marshall Space Flight Center, Third Conference on Artificial Intelligence for Space Applications, Part 1 1-7 (SEE N88-16360 08-61); NASA. Marshall Space
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  • 54
    Publication Date: 2013-08-31
    Description: Programming of the space station is to be done in the Ada programming language. A breadboard of selected parts of the work package for Marshall Space Flight Center is to be built, and programming this small part will be a good testing ground for Ada. One coding of the upper levels of the design brings out several problems with top-down design when it is to be carried out strictly within the language. Ada is evaluated on the basis of this experience, and the points raised are compared with other experience as related in the literature. Rapid prototyping is another approach to the initial programming; several different types of prototypes are discussed, and compared with the art of specification. Some solutions are proposed and a number of recommendations presented.
    Keywords: COMPUTER PROGRAMMING AND SOFTWARE
    Type: NASA. Marshall Space Flight Center, Research Reports: 1987 NASA(ASEE Summer Faculty Fellowship Program; 22 p
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  • 55
    Publication Date: 2013-08-31
    Description: This description of the Transportable Applications Executive (TAE) is intended to serve to test the feasibility of its use as the Space Station User Interface Language (SSUIL). TAE was developed by the Space Data and Computing Division, Space and Earth Sciences Directorate of NASA/GSFC, and by Century Computing, Inc. in 1980. TAE is an executive program which ties a system of application programs into a single easily operated whole and supports users' operations of programs through a consistent friendly and flexible interactive user interface. TAE also supplies the interface between the user and the various application programs in a particular computer system. It appears to be an effective user interface for infrequent as well as for expert users.
    Keywords: COMPUTER PROGRAMMING AND SOFTWARE
    Type: NASA. Marshall Space Flight Center, Research Reports: 1987 NASA(ASEE Summer Faculty Fellowship Program; 22 p
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  • 56
    Publication Date: 2013-08-31
    Description: The focus of this research is the investigation of data structures and associated search algorithms for automated fault diagnosis of complex systems such as the Hubble Space Telescope. Such data structures and algorithms will form the basis of a more sophisticated Knowledge Based Fault Diagnosis System. As a part of the research, several prototypes were written in VAXLISP and implemented on one of the VAX-11/780's at the Marshall Space Flight Center. This report describes and gives the rationale for both the data structures and algorithms selected. A brief discussion of a user interface is also included.
    Keywords: COMPUTER PROGRAMMING AND SOFTWARE
    Type: NASA. Marshall Space Flight Center, Research Reports: 1987 NASA(ASEE Summer Faculty Fellowship Program; 15 p
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  • 57
    Publication Date: 2013-08-31
    Description: Experience with the three-dimensional (3-D), chimera grid embedding scheme is described. Applications of the inviscid version to a multiple-body configuration, a wind/body/tail configuration, and an estimate of wind tunnel wall interference are described. Applications to viscous flows include a 3-D cavity and another multi-body configuration. A variety of grid generators is used, and several embedding strategies are described.
    Keywords: COMPUTER PROGRAMMING AND SOFTWARE
    Type: NASA. Ames Research Center, Supercomputing in Aerospace; p 271-277
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  • 58
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    In:  CASI
    Publication Date: 2013-08-31
    Description: With the advent of supercomputers, modern computational chemistry algorithms and codes, a powerful tool was created to help fill NASA's continuing need for information on the properties of matter in hostile or unusual environments. Computational resources provided under the National Aerodynamics Simulator (NAS) program were a cornerstone for recent advancements in this field. Properties of gases, materials, and their interactions can be determined from solutions of the governing equations. In the case of gases, for example, radiative transition probabilites per particle, bond-dissociation energies, and rates of simple chemical reactions can be determined computationally as reliably as from experiment. The data are proving to be quite valuable in providing inputs to real-gas flow simulation codes used to compute aerothermodynamic loads on NASA's aeroassist orbital transfer vehicles and a host of problems related to the National Aerospace Plane Program. Although more approximate, similar solutions can be obtained for ensembles of atoms simulating small particles of materials with and without the presence of gases. Computational chemistry has application in studying catalysis, properties of polymers, all of interest to various NASA missions, including those previously mentioned. In addition to discussing these applications of computational chemistry within NASA, the governing equations and the need for supercomputers for their solution is outlined.
    Keywords: COMPUTER PROGRAMMING AND SOFTWARE
    Type: Supercomputing in Aerospace; p 299-311
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  • 59
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    In:  CASI
    Publication Date: 2013-08-31
    Description: The past decade has seen considerable activity in algorithm development for the Navier-Stokes equations. This has resulted in a wide variety of useful new techniques. Some examples for the numerical solution of the Navier-Stokes equations are presented, divided into two parts. One is devoted to the incompressible Navier-Stokes equations, and the other to the compressible form.
    Keywords: COMPUTER PROGRAMMING AND SOFTWARE
    Type: Supercomputing in Aerospace; p 191-200
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  • 60
    Publication Date: 2013-08-31
    Description: The increasing development of small microprocessor systems has allowed the use of more advanced software in the area of control systems. This paper discusses the development of software for small Space Shuttle Getaway Special Project payloads using payload G285 as a case example. The development process behind a space related software package (as in any software package) is a major factor. The design process for G285 is discussed in some detail along with the general scheme behind data acquisition and thermal environmental control for a space related payload. Additionally, key concepts in a software system concern the implementation of redundant systems, error detection, and error response. All of these factors are discussed.
    Keywords: COMPUTER PROGRAMMING AND SOFTWARE
    Type: NASA. Goddard Space Flight Center The 1986 Get Away Special Experimenter's Symposium; p 71-78
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  • 61
    Publication Date: 2013-08-31
    Description: It has been shown by Fiacco that convexity or concavity of the optimal value of a parametric nonlinear programming problem can readily be exploited to calculate global parametric upper and lower bounds on the optimal value function. The approach is attractive because it involves manipulation of information normally required to characterize solution optimality. A procedure is briefly described for calculating and improving the bounds as well as its extensions to generalized convex and concave functions. Several areas of applications are also indicated.
    Keywords: COMPUTER PROGRAMMING AND SOFTWARE
    Type: NASA. Langley Research Center Sensitivity Analysis in Engineering; p 11-18
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  • 62
    Publication Date: 2011-08-19
    Description: Large, randomly sparse matrix vector products are important in a number of applications in computational chemistry, such as matrix diagonalization and the solution of simultaneous equations. Vectorization of this process is considered for the CRAY XMP, CRAY 2, and CYBER 205, using a matrix of dimension of 20,000 with from 1 percent to 6 percent nonzeros. Efficient scatter/gather capabilities add coding flexibility and yield significant improvements in performance. For the CYBER 205, it is shown that minor changes in the IO can reduce the CPU time by a factor of 50. Similar changes in the CRAY codes make a far smaller improvement.
    Keywords: COMPUTER PROGRAMMING AND SOFTWARE
    Type: Journal of Computational Chemistry (ISSN 0192-8651); 8; 5, 19
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  • 63
    Publication Date: 2013-08-31
    Description: Engineering Automation at Northrop encompasses the various design and analytical phases of air vehicle development. Design systems addresses automation of engineering/tooling design and computer aided manufacturing processes. The analysis systems automate aeroelastic modeling and postprocessing analysis results. These systems interface with aircraft loft and geometric entities thru localized transfer techniques. However, total integration effort based on a geometric database nucleus with peripheral design, analytical and manufacturing systems is well underway. An outline of the present and future trends is presented to help channel the RPI effort in this direction.
    Keywords: COMPUTER PROGRAMMING AND SOFTWARE
    Type: Rensselaer Polytechnic Inst., Workshop on the Integration of Finite Element Modeling with Geometric Modeling; 32 p
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  • 64
    Publication Date: 2013-08-31
    Description: How graphics postprocessing techniques are currently used to examine the results of 3-D nonlinear analyses, some new techniques which take advantage of recent technology, and how these results relate to both the finite element model and its geometric parent are reviewed.
    Keywords: COMPUTER PROGRAMMING AND SOFTWARE
    Type: Rensselaer Polytechnic Inst., Workshop on the Integration of Finite Element Modeling with Geometric Modeling; 8 p
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  • 65
    Publication Date: 2013-08-31
    Description: Finite element meshes derived automatically from solid models through recursive spatial subdivision schemes (octrees) can be made to inherit the hierarchical structure and the spatial addressability intrinsic to the underlying grid. These two properties, together with the geometric regularity that can also be built into the mesh, make octree based meshes ideally suited for efficient analysis and self-adaptive remeshing and reanalysis. The element decomposition of the octal cells that intersect the boundary of the domain is discussed. The problem, central to octree based meshing, is solved by combining template mapping and element extraction into a procedure that utilizes both constructive solid geometry and boundary representation techniques. Boundary cells that are not intersected by the edge of the domain boundary are easily mapped to predefined element topology. Cells containing edges (and vertices) are first transformed into a planar polyhedron and then triangulated via element extractor. The modeling environments required for the derivation of planar polyhedra and for element extraction are analyzed.
    Keywords: COMPUTER PROGRAMMING AND SOFTWARE
    Type: Rensselaer Polytechnic Inst., Workshop on the Integration of Finite Element Modeling with Geometric Modeling; 15 p
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  • 66
    Publication Date: 2013-08-31
    Description: Finite element modeling is dominated by geometric modeling type operations. Therefore, an effective interface to geometric modeling requires access to both the model and the modeling functionality used to create it. The use of a dynamic interface that addresses these needs through the use of boundary data structures and geometric operators is discussed.
    Keywords: COMPUTER PROGRAMMING AND SOFTWARE
    Type: Workshop on the Integration of Finite Element Modeling with Geometric Modeling; 12 p
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  • 67
    Publication Date: 2013-08-31
    Description: Presented is a compilation of the history of a two-month project concerned with a survey, evaluation, and specification of a new computer system for the Applications Software Branch of the Software and Data Management Division of Information and Electronic Systems Laboratory of Marshall Space Flight Center, NASA. Information gathering consisted of discussions and surveys of branch activities, evaluation of computer manufacturer literature, and presentations by vendors. Information gathering was followed by evaluation of their systems. The criteria of the latter were: the (tentative) architecture selected for the new system, type of network architecture supported, software tools, and to some extent the price. The information received from the vendors, as well as additional research, lead to detailed design of a suitable system. This design included considerations of hardware and software environments as well as personnel issues such as training. Design of the system culminated in a recommendation for a new computing system for the Branch.
    Keywords: COMPUTER PROGRAMMING AND SOFTWARE
    Type: NASA. Marshall Space Flight Center, Research Reports: 1987 NASA(ASEE Summer Faculty Fellowship Program; 43 p
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  • 68
    Publication Date: 2013-08-31
    Description: An overview of the acceptance software and certification testing procedures is presented.
    Keywords: COMPUTER PROGRAMMING AND SOFTWARE
    Type: Experiments in Fault Tolerant Software Reliability; 36 p
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  • 69
    Publication Date: 2013-08-31
    Description: It is a fact that adjacent pixels in a Voyager image are very similar in grey level. This fact can be used in conjunction with the Maximum-Likelihood Convolutional Decoder (MCD) to decrease the error rate when decoding a picture from Voyager. Implementing this idea would require no changes in the Voyager spacecraft and could be used as a backup to the current system without too much expenditure, so the feasibility of it and the possible gains for Voyager were investigated. Simulations have shown that the gain could be as much as 2 dB at certain error rates, and experiments with real data inspired new ideas on ways to get the most information possible out of the received symbol stream.
    Keywords: COMPUTER PROGRAMMING AND SOFTWARE
    Type: The Telecommunications and Data Acquisition Report; p 32-41
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  • 70
    Publication Date: 2013-08-31
    Description: Effective user interface design in software systems is a complex task that takes place without adequate modeling tools. By combining state transition diagrams and the storyboard technique of filmmakers, State Transition Storyboards were developed to provide a detailed modeling technique for the Goldstone Solar System Radar Data Acquisition System human-machine interface. Illustrations are included with a description of the modeling technique.
    Keywords: COMPUTER PROGRAMMING AND SOFTWARE
    Type: The Telecommunications and Data Acquisition Report; p 94-102
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  • 71
    Publication Date: 2013-08-31
    Description: The elements of a simulation program written in Ada were developed. The program will eventually serve as a data generator of typical readings from various space station equipment involved with Communications and Tracking, and will simulate various scenarios that may arise due to equipment malfunction or failure, power failure, etc. In addition, an evaluation of the Ada language was made from the viewpoint of a FORTRAN programmer learning Ada for the first time. Various strengths and difficulties associated with the learning and use of Ada are considered.
    Keywords: COMPUTER PROGRAMMING AND SOFTWARE
    Type: NASA. Lyndon B.; NASA. Lyndon B. John
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  • 72
    Publication Date: 2013-08-31
    Description: A new methodology to increase the utility of the Massively Parallel Processor (MPP) was developed, and is presented as an addition to the current methods of using the MPP. This methodology provides for the development of an MPP side abstraction layer that is callable from any host side high level language. Routines in the abstraction layer have the option of using a powerful software tool for accessing the stager as virtual memory. An additional abstraction layer that allows for remote access to the MPP via DECnet is discussed. This integrated approach to programming the MPP is a valuable tool for the implementation of interactive user driver systems that require the computational capabilities of the MPP as well as a controlled user view. It is expected that this methodology will be used to integrate the MPP into many such systems, and thus promote greater use of the MPP by scientific researchers who are accustomed to user friendly environments.
    Keywords: COMPUTER PROGRAMMING AND SOFTWARE
    Type: NASA. Goddard Space Flight Center, Frontiers of Massively Parallel Scientific Computation; p 271-273
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  • 73
    Publication Date: 2013-08-31
    Description: In pursuit of real time animation of computer simulated space plasma phenomena, the code was rewritten for the Massively Parallel Processor (MPP). The program creates a dynamic representation of the global bowshock which is based on actual spacecraft data and designed for three dimensional graphic output. This output consists of time slice sequences which make up the frames of the animation. With the MPP, 16384, 512 or 4 frames can be calculated simultaneously depending upon which characteristic is being computed. The run time was greatly reduced which promotes the rapid sequence of images and makes real time animation a foreseeable goal. The addition of more complex phenomenology in the constructed computer images is now possible and work proceeds to generate these images.
    Keywords: COMPUTER PROGRAMMING AND SOFTWARE
    Type: NASA. Goddard Space Flight Center, Frontiers of Massively Parallel Scientific Computation; p 223-225
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  • 74
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    In:  CASI
    Publication Date: 2013-08-31
    Description: Generating graphics to faithfully represent information can be a computationally intensive task. A way of using the Massively Parallel Processor to generate images by ray tracing is presented. This technique uses sort computation, a method of performing generalized routing interspersed with computation on a single-instruction-multiple-data (SIMD) computer.
    Keywords: COMPUTER PROGRAMMING AND SOFTWARE
    Type: Frontiers of Massively Parallel Scientific Computation; p 211-215
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  • 75
    Publication Date: 2013-08-31
    Description: The capability was developed of rapidly producing visual representations of large, complex, multi-dimensional space and earth sciences data sets via the implementation of computer graphics modeling techniques on the Massively Parallel Processor (MPP) by employing techniques recently developed for typically non-scientific applications. Such capabilities can provide a new and valuable tool for the understanding of complex scientific data, and a new application of parallel computing via the MPP. A prototype system with such capabilities was developed and integrated into the National Space Science Data Center's (NSSDC) Pilot Climate Data System (PCDS) data-independent environment for computer graphics data display to provide easy access to users. While developing these capabilities, several problems had to be solved independently of the actual use of the MPP, all of which are outlined.
    Keywords: COMPUTER PROGRAMMING AND SOFTWARE
    Type: Frontiers of Massively Parallel Scientific Computation; p 217-222
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  • 76
    Publication Date: 2013-08-31
    Description: Classifiers are often used to produce land cover maps from multispectral Earth observation imagery. Conventionally, these classifiers have been designed to exploit the spectral information contained in the imagery. Very few classifiers exploit the spatial information content of the imagery, and the few that do rarely exploit spatial information content in conjunction with spectral and/or temporal information. A contextual classifier that exploits spatial and spectral information in combination through a general statistical approach was studied. Early test results obtained from an implementation of the classifier on a VAX-11/780 minicomputer were encouraging, but they are of limited meaning because they were produced from small data sets. An implementation of the contextual classifier is presented on the Massively Parallel Processor (MPP) at Goddard that for the first time makes feasible the testing of the classifier on large data sets.
    Keywords: COMPUTER PROGRAMMING AND SOFTWARE
    Type: Frontiers of Massively Parallel Scientific Computation; p 171-181
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  • 77
    Publication Date: 2013-08-31
    Description: Massively Parallel Processor algorithms were developed for the interactive manipulation of flat shaded digital terrain models defined over grids. The emphasis is on real time manipulation of stereo images. Standard graphics transformations are applied to a 128 x 128 grid of elevations followed by shading and a perspective projection to produce the right eye image. The surface is then rendered using a simple painter's algorithm for hidden surface removal. The left eye image is produced by rotating the surface 6 degs about the viewer's y axis followed by a perspective projection and rendering of the image as described above. The left and right eye images are then presented on a graphics device using standard stereo technology. Performance evaluations and comparisons are presented.
    Keywords: COMPUTER PROGRAMMING AND SOFTWARE
    Type: NASA. Goddard Space Flight Center, Frontiers of Massively Parallel Scientific Computation; p 135-140
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  • 78
    Publication Date: 2013-08-31
    Description: Balanced correlation method and the Maximum Entropy Method (MEM) were implemented to reconstruct a laboratory X-ray source as imaged by a Uniformly Redundant Array (URA) system. Although the MEM method has advantages over the balanced correlation method, it is computationally time consuming because of the iterative nature of its solution. Massively Parallel Processing, with its parallel array structure is ideally suited for such computations. These preliminary results indicate that it is possible to use the MEM method in future coded-aperture experiments with the help of the MPP.
    Keywords: COMPUTER PROGRAMMING AND SOFTWARE
    Type: Frontiers of Massively Parallel Scientific Computation; p 111-119
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  • 79
    Publication Date: 2013-08-31
    Description: A method is described for algebraic image restoration capable of treating astronomical images. For a typical 500 x 500 image, direct algebraic restoration would require the solution of a 250,000 x 250,000 linear system. The block iterative approach is used to reduce the problem to solving 4900 121 x 121 linear systems. The algorithm was implemented on the Goddard Massively Parallel Processor, which can solve a 121 x 121 system in approximately 0.06 seconds. Examples are shown of the results for various astronomical images.
    Keywords: COMPUTER PROGRAMMING AND SOFTWARE
    Type: Frontiers of Massively Parallel Scientific Computation; p 99-109
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  • 80
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    In:  CASI
    Publication Date: 2013-08-31
    Description: Many of the models now used in science and engineering are over a century old. And most of them can be implemented on modern digital computers only with considerable difficulty. Some new basic models are discussed which are much more directly suitable for digital computer simulation. The fundamental principle is that the models considered herein are as suitable as possible for implementation on digital computers. It is then a matter of scientific analysis to determine whether such models can reproduce the behavior seen in physical and other systems. Such analysis was carried out in several cases, and the results are very encouraging.
    Keywords: COMPUTER PROGRAMMING AND SOFTWARE
    Type: NASA. Goddard Space Flight Center, Frontiers of Massively Parallel Scientific Computation; p 87-95
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  • 81
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    In:  CASI
    Publication Date: 2013-08-31
    Description: The Massively Parallel Processor (MPP) is an ideal machine for computer experiments with simulated neural nets as well as more general cellular automata. Experiments using the MPP with a formal model neural network are described. The results on problem mapping and computational efficiency apply equally well to the neural nets of Hopfield, Hinton et al., and Geman and Geman.
    Keywords: COMPUTER PROGRAMMING AND SOFTWARE
    Type: NASA. Goddard Space Flight Center, Frontiers of Massively Parallel Scientific Computation; p 69-73
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  • 82
    Publication Date: 2013-08-31
    Description: The Applicative Programming System Architecture (APSA) combines an applicative language interpreter with a novel parallel computer architecture that is well suited for Very Large Scale Integration (VLSI) implementation. The Massively Parallel Processor (MPP) can simulate VLSI circuits by allocating one processing element in its square array to an area on a square VLSI chip. As long as there are not too many long data paths, the MPP can simulate a VLSI clock cycle very rapidly. The APSA circuit contains a binary tree with a few long paths and many short ones. A skewed H-tree layout allows every processing element to simulate a leaf cell and up to four tree nodes, with no loss in parallelism. Emulation of a key APSA algorithm on the MPP resulted in performance 16,000 times faster than a Vax. This speed will make it possible for the APSA language interpreter to run fast enough to support research in parallel list processing algorithms.
    Keywords: COMPUTER PROGRAMMING AND SOFTWARE
    Type: NASA. Goddard Space Flight Center, Frontiers of Massively Parallel Scientific Computation; p 75-84
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  • 83
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    In:  CASI
    Publication Date: 2013-08-31
    Description: Research in cognitive science suggests that much of cognition involves the rapid manipulation of complex data structures. However, it is very unclear how this could be realized in neural networks or connectionist systems. A core question is: how could the interconnectivity of items in an abstract-level data structure be neurally encoded? The answer appeals mainly to positional relationships between activity patterns within neural arrays, rather than directly to neural connections in the traditional way. The new method was initially devised to account for abstract symbolic data structures, but it also supports cognitively useful spatial analogue, image-like representations. As the neural model is based on massive, uniform, parallel computations over 2D arrays, the massively parallel processor is a convenient tool for simulation work, although there are complications in using the machine to the fullest advantage. An MPP Pascal simulation program for a small pilot version of the model is running.
    Keywords: COMPUTER PROGRAMMING AND SOFTWARE
    Type: NASA. Goddard Space Flight Center, Frontiers of Massively Parallel Scientific Computation; p 59-68
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  • 84
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    In:  CASI
    Publication Date: 2013-08-31
    Description: The complexity of codes for solutions of real aerodynamic problems has progressed from simple two-dimensional models to three-dimensional inviscid and viscous models. As the algorithms used in the codes increased in accuracy, speed and robustness, the codes were steadily incorporated into standard design processes. The highly sophisticated codes, which provide solutions to the truly complex flows, require computers with large memory and high computational speed. The advent of high-speed supercomputers, such that the solutions of these complex flows become more practical, permits the introduction of the codes into the design system at an earlier stage. The results of several codes which either were already introduced into the design process or are rapidly in the process of becoming so, are presented. The codes fall into the area of turbomachinery aerodynamics and hypersonic propulsion. In the former category, results are presented for three-dimensional inviscid and viscous flows through nozzle and unducted fan bladerows. In the latter category, results are presented for two-dimensional inviscid and viscous flows for hypersonic vehicle forebodies and engine inlets.
    Keywords: COMPUTER PROGRAMMING AND SOFTWARE
    Type: NASA. Ames Research Center, Supercomputing in Aerospace; p 149-158
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  • 85
    Publication Date: 2013-08-31
    Description: The advent of direct numerical simulations of turbulence has opened avenues for research on turbulence physics and turbulence modeling. Direct numerical simulation provides values for anything that the scientist or modeler would like to know about the flow. An overview of some recent advances in the physical understanding of turbulence and in turbulence modeling obtained through such simulations is presented.
    Keywords: COMPUTER PROGRAMMING AND SOFTWARE
    Type: NASA. Ames Research Center, Supercomputing in Aerospace; p 201-209
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  • 86
    Publication Date: 2013-08-31
    Description: The development of the technology of ballistics as applied to gun launched Army weapon systems is the main objective of research at the U.S. Army Ballistic Research Laboratory (BRL). The primary research programs at the BRL consist of three major ballistic disciplines: exterior, interior, and terminal. The work done at the BRL in these areas was traditionally highly dependent on experimental testing. A considerable emphasis was placed on the development of computational modeling to augment the experimental testing in the development cycle; however, the impact of the computational modeling to this date is modest. With the availability of supercomputer computational resources recently installed at the BRL, a new emphasis on the application of computational modeling to ballistics technology is taking place. The major application areas are outlined which are receiving considerable attention at the BRL at present and to indicate the modeling approaches involved. An attempt was made to give some information as to the degree of success achieved and indicate the areas of greatest need.
    Keywords: COMPUTER PROGRAMMING AND SOFTWARE
    Type: NASA. Ames Research Center, Supercomputing in Aerospace; p 175-182
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  • 87
    Publication Date: 2017-10-02
    Description: In advanced robot control problems, on-line computation of inverse Jacobian solution is frequently required. Parallel processing architecture is an effective way to reduce computation time. A parallel processing architecture is developed for the inverse Jacobian (inverse differential kinematic equation) of the PUMA arm. The proposed pipeline/parallel algorithm can be inplemented on an IC chip using systolic linear arrays. This implementation requires 27 processing cells and 25 time units. Computation time is thus significantly reduced.
    Keywords: COMPUTER PROGRAMMING AND SOFTWARE
    Type: Jet Propulsion Lab., California Inst. of Tech., Proceedings of the Workshop on Space Telerobotics, Volume 3; p 317-324
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  • 88
    Publication Date: 2017-10-02
    Description: An experimental telerobotics (TR) simulation suitable for studying human operator (H.O.) performance is described. Simple manipulator pick-and-place and tracking tasks allowed quantitative comparison of a number of calligraphic display viewing conditions. A number of control modes could be compared in this TR simulation, including displacement, rate and acceleratory control using position and force joysticks. A homeomorphic controller turned out to be no better than joysticks; the adaptive properties of the H.O. can apparently permit quite good control over a variety of controller configurations and control modes. Training by optimal control example seemed helpful in preliminary experiments. An introduced communication delay was found to produce decrease in performance. In considerable part, this difficulty could be compensated for by preview control information. That neurological control of normal human movement contains a data period of 0.2 second may relate to this robustness of H.O. control to delay. The Ames-Berkeley enhanced perspective display was utilized in conjunction with an experimental helmet mounted display system (HMD) that provided stereoscopic enhanced views.
    Keywords: COMPUTER PROGRAMMING AND SOFTWARE
    Type: Jet Propulsion Lab., California Inst. of Tech., Proceedings of the Workshop on Space Telerobotics, Volume 2; p 413-421
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  • 89
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    In:  CASI
    Publication Date: 2017-10-02
    Description: The properties of a temporal language are determined by its constituent elements: the temporal objects which it can represent, the attributes of those objects, the relationships between them, the axioms which define the default relationships, and the rules which define the statements that can be formulated. The methods of inference which can be applied to a temporal language are derived in part from a small number of axioms which define the meaning of equality and order and how those relationships can be propagated. More complex inferences involve detailed analysis of the stated relationships. Perhaps the most challenging area of temporal inference is reasoning over disjunctive temporal constraints. Simple forms of disjunction do not sufficiently increase the expressive power of a language while unrestricted use of disjunction makes the analysis NP-hard. In many cases a set of disjunctive constraints can be converted to disjunctive normal form and familiar methods of inference can be applied to the conjunctive sub-expressions. This process itself is NP-hard but it is made more tractable by careful expansion of a tree-structured search space.
    Keywords: COMPUTER PROGRAMMING AND SOFTWARE
    Type: Jet Propulsion Lab., California Inst. of Tech., Proceedings of the Workshop on Space Telerobotics, Volume 3; p 9-15
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  • 90
    Publication Date: 2017-10-02
    Description: The present work on robot instructability is based on an ongoing effort to apply modern manipulation technology to serve the needs of the handicapped. The Stanford/VA Robotic Aid is a mobile manipulation system that is being developed to assist severely disabled persons (quadriplegics) in performing simple activities of everyday living in a homelike, unstructured environment. It consists of two major components: a nine degree-of-freedom manipulator and a stationary control console. In the work presented here, only the motions of the Robotic Aid's omnidirectional motion base have been considered, i.e., the six degrees of freedom of the arm and gripper have been ignored. The goal has been to develop some basic software tools for commanding the robot's motions in an enclosed room containing a few objects such as tables, chairs, and rugs. In the present work, the environmental model takes the form of a two-dimensional map with objects represented by polygons. Admittedly, such a highly simplified scheme bears little resemblance to the elaborate cognitive models of reality that are used in normal human discourse. In particular, the polygonal model is given a priori and does not contain any perceptual elements: there is no polygon sensor on board the mobile robot.
    Keywords: COMPUTER PROGRAMMING AND SOFTWARE
    Type: Jet Propulsion Lab., California Inst. of Tech., Proceedings of the Workshop on Space Telerobotics, Volume 2; p 381-391
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  • 91
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    In:  Other Sources
    Publication Date: 2019-01-25
    Description: Finite element meshes derived automatically from solid models through recursive spatial subdivision schemes (octrees) can be made to inherit the hierarchical structure and the spatial addressability intrinsic to the underlying grid. These two properties, together with the geometric regularity that can also be built into the mesh, make octree based meshes ideally suited for efficient analysis and self-adaptive remeshing and reanalysis. The element decomposition of the octal cells that intersect the boundary of the domain is emphasized. The problem, central to octree based meshing, is solved by combining template mapping and element extraction into a procedure that utilizes both constructive solid geometry and boundary respresentation techniques. Boundary cells that are not intersected by the edge of the domain boundary are easily mapped to predefined element topology. Cells containing edges (and vertices) are first transformed into a planar polyhedron and then triangulated via element extractors. The modeling environments required for the derivation of planar polyhedra and for element extraction are analyzed.
    Keywords: COMPUTER PROGRAMMING AND SOFTWARE
    Type: Rensselaer Polytechnic Inst., Workshop on the Integration of Finite Element Modeling with Geometric Modeling; 1 p
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  • 92
    Publication Date: 2018-12-01
    Description: Semi-Markov models (a generalization of Markov models) can be used to calculate the reliability of virtually any fault-tolerant system. However, the process of delineating all of the states and transitions in the model of a complex system can be devastatingly tedious and error-prone. The ASSIST program allows the user to describe the semi-Markov model in a high-level language. Instead of specifying the individual states of the model, the user specifies the rules governing the behavior of the system, and these are used by ASSIST to automatically generate the model. A small number of statements in the abstract language can be used to describe a very large, complex model. Because no assumptions are made about the system being modeled, the ASSIST program can be used to generate models describing the behavior of any type of system. The ASSIST program and its input language are described and illustrated by examples.
    Keywords: COMPUTER PROGRAMMING AND SOFTWARE
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  • 93
    Publication Date: 2018-12-01
    Description: A traditional programming technique for controlling the display of optional flight information in a civil transport cockpit is compared to a rule-based technique for the same function. This application required complex decision logic and a frequently modified rule base. The techniques are evaluated for execution efficiency and implementation ease; the criterion used to calculate the execution efficiency is the total number of steps required to isolate hypotheses that were true and the criteria used to evaluate the implementability are ease of modification and verification and explanation capability. It is observed that the traditional program is more efficient than the rule-based program; however, the rule-based programming technique is more applicable for improving programmer productivity.
    Keywords: COMPUTER PROGRAMMING AND SOFTWARE
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  • 94
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    In:  CASI
    Publication Date: 2019-06-28
    Description: The Space Station contains safety critical computer software components in systems that can affect life and vital property. These components require a multilevel secure system that provides dynamic access control of the data and processes involved. A study is under way to define requirements for a security model providing access control through level B3 of the Orange Book. The model will be prototyped at NASA-Johnson Space Center.
    Keywords: COMPUTER PROGRAMMING AND SOFTWARE
    Type: NASA-CR-187656 , NAS 1.26:187656
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  • 95
    Publication Date: 2019-06-28
    Description: NASA's software engineering and Ada skill base are assessed and information that may result in new models for software engineering, Ada training plans, and curricula are provided. A quantitative assessment which reflects the requirements for software engineering and Ada training across NASA is provided. A recommended implementation plan including a suggested curriculum with associated duration per course and suggested means of delivery is also provided. The distinction between education and training is made. Although it was directed to focus on NASA's need for the latter, the key relationships to software engineering education are also identified. A rationale and strategy for implementing a life cycle education and training program are detailed in support of improved software engineering practices and the transition to Ada.
    Keywords: COMPUTER PROGRAMMING AND SOFTWARE
    Type: NASA-CR-187390 , NAS 1.26:187390
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  • 96
    Publication Date: 2019-06-28
    Description: An Initial Graphics Exchange Specification (IGES) test file is called the 28 Entity IGES Test File. This file contains 28 geometric and annotation entities which are considered the basic entities that an IGES translator for any CAD system should support. The main purpose was to determine how the IGES preprocessor supports the 28 entities through recreation of the 28 Entity IGES Test File on the ComputerVision CADDS 4X. Test procedure is described and test results are presented.
    Keywords: COMPUTER PROGRAMMING AND SOFTWARE
    Type: NASA-CR-187403 , NAS 1.26:187403
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  • 97
    Publication Date: 2019-06-28
    Description: The objective was to introduce the basic terminology and concepts of software engineering and Ada. The life cycle model is reviewed. The application of the goals and principles of software engineering is applied. An introductory understanding of the features of the Ada language is gained. Topics addressed include: the software crises; the mandate of the Space Station Program; software life cycle model; software engineering; and Ada under the software engineering umbrella.
    Keywords: COMPUTER PROGRAMMING AND SOFTWARE
    Type: NASA-CR-187266 , NAS 1.26:187266 , Clear Lake, TX; United States
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  • 98
    Publication Date: 2019-06-28
    Description: System interface sets (SIS) for large, complex, non-stop, distributed systems are examined. The SIS of the Space Station Program (SSP) was selected as the focus of this study because an appropriate virtual interface specification of the SIS is believed to have the most potential to free the project from four life cycle tyrannies which are rooted in a dependance on either a proprietary or particular instance of: operating systems, data management systems, communications systems, and instruction set architectures. The static perspective of the common Ada programming support environment interface set (CAIS) and the portable common execution environment (PCEE) activities are discussed. Also, the dynamic perspective of the PCEE is addressed.
    Keywords: COMPUTER PROGRAMMING AND SOFTWARE
    Type: NASA-CR-187399 , NAS 1.26:187399
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  • 99
    Publication Date: 2019-06-28
    Description: This report is a user's manual for version 2.1 of pEst, a FORTRAN 77 computer program for interactive parameter estimation in nonlinear dynamic systems. The pEst program allows the user complete generality in definig the nonlinear equations of motion used in the analysis. The equations of motion are specified by a set of FORTRAN subroutines; a set of routines for a general aircraft model is supplied with the program and is described in the report. The report also briefly discusses the scope of the parameter estimation problem the program addresses. The report gives detailed explanations of the purpose and usage of all available program commands and a description of the computational algorithms used in the program.
    Keywords: COMPUTER PROGRAMMING AND SOFTWARE
    Type: NASA-TM-88280 , H-1390 , NAS 1.15:88280
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  • 100
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    In:  CASI
    Publication Date: 2019-06-28
    Description: The developed Earth Science and Application Division (ESAD) system/software provides the research scientist with the following capabilities: an extensive data base management capibility to convert various experiment data types into a standard format; and interactive analysis and display package (AVE80); an interactive imaging/color graphics capability utilizing the Apple III and IBM PC workstations integrated into the ESAD computer system; and local and remote smart-terminal capability which provides color video, graphics, and Laserjet output. Recommendations for updating and enhancing the performance of the ESAD computer system are listed.
    Keywords: COMPUTER PROGRAMMING AND SOFTWARE
    Type: NASA-CR-179151 , NAS 1.26:179151 , ACI-072087-FR
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