33 research outputs found
An engineering approach to automatic programming
An exploratory study of the automatic generation and optimization of symbolic programs using DECOM - a prototypical requirement specification model implemented in pure LISP was undertaken. It was concluded, on the basis of this study, that symbolic processing languages such as LISP can support a style of programming based upon formal transformation and dependent upon the expression of constraints in an object-oriented environment. Such languages can represent all aspects of the software generation process (including heuristic algorithms for effecting parallel search) as dynamic processes since data and program are represented in a uniform format
Parallel processing for scientific computations
The main contribution of the effort in the last two years is the introduction of the MOPPS system. After doing extensive literature search, we introduced the system which is described next. MOPPS employs a new solution to the problem of managing programs which solve scientific and engineering applications on a distributed processing environment. Autonomous computers cooperate efficiently in solving large scientific problems with this solution. MOPPS has the advantage of not assuming the presence of any particular network topology or configuration, computer architecture, or operating system. It imposes little overhead on network and processor resources while efficiently managing programs concurrently. The core of MOPPS is an intelligent program manager that builds a knowledge base of the execution performance of the parallel programs it is managing under various conditions. The manager applies this knowledge to improve the performance of future runs. The program manager learns from experience
Fifth Conference on Artificial Intelligence for Space Applications
The Fifth Conference on Artificial Intelligence for Space Applications brings together diverse technical and scientific work in order to help those who employ AI methods in space applications to identify common goals and to address issues of general interest in the AI community. Topics include the following: automation for Space Station; intelligent control, testing, and fault diagnosis; robotics and vision; planning and scheduling; simulation, modeling, and tutoring; development tools and automatic programming; knowledge representation and acquisition; and knowledge base/data base integration
Redundant disk arrays: Reliable, parallel secondary storage
During the past decade, advances in processor and memory technology have given rise to increases in computational performance that far outstrip increases in the performance of secondary storage technology. Coupled with emerging small-disk technology, disk arrays provide the cost, volume, and capacity of current disk subsystems, by leveraging parallelism, many times their performance. Unfortunately, arrays of small disks may have much higher failure rates than the single large disks they replace. Redundant arrays of inexpensive disks (RAID) use simple redundancy schemes to provide high data reliability. The data encoding, performance, and reliability of redundant disk arrays are investigated. Organizing redundant data into a disk array is treated as a coding problem. Among alternatives examined, codes as simple as parity are shown to effectively correct single, self-identifying disk failures
EDITH - experimental in-torus maintenance system for fusion reactors. Final report
Experimentelles Handhabungssystem für Wartungsarbeiten im Torus eines Fusionsreaktors
Wegen der besonderen Umgebungsbedingungen - erhöhte -Strahlung und Temperatur - können Reparaturarbeiten in der Plasmakammer eines Fusionsreaktors wie NET/ITER nur mittels eines fernbedienten Handhabungssystems durchgeführt werden. EDITH (Experimental Device for In-Torus Handling) ist der Prototyp eines solchen Systems. Es basiert auf einem Vielgelenkarm, der für die jeweiligen Aufgaben mit verschiedenen Endeffektoren bzw. Werkzeugen ausgerüstet ist. EDITH ist die zentrale Komponente eines Teststandes, mit dem in Originalgröße in einem nachgebildeten Ausschnitt einer Plasmakammer Fernhantierungsvorgänge experimentell untersucht werden. Exemplarisch für solche Aufgaben wurde der fernbediente Austausch von Schutzziegeln und Divertorplatten durchgeführt. Um den Operateuren eine schnelle und zuverlässige Durchführung der Arbeiten zu ermöglichen, wurde ein neuartiges Leit- und Steuersystem entwickelt. Das Leitsystem bildet in Form einer Fernhandhabungs-Arbeitsstation zusammen mit den Servomanipulatoren die Mensch-Maschine-Schnittstelle zur Steuerung und Überwachung aller Geräte. Die Arbeitsstation unterstützt die Operateure bei allen manuell zu steuernden Arbeiten, bei der Planung, Simulation und Programmierung automatisch durchzuführender Teilaufgaben und dient mit ihrem multimedialen Dokumentationssystem als ständig verfügbare Informationsquelle. Bei der Konzeption der Steuerung standen das dynamische Verhalten, die Betriebssicherheit und die Kopplung an das Leitsystem im Vordergrund. Qualifikationstests und erste Experimentiererfahrungen bestätigten, daß mit der bei FZK entwickelten Fernhantierungstechnik die gestellten Aufgaben sicher, zuverlässig und in vertretbarer Zeit ausgeführt werden können
NASA Tech Briefs, July 1993
Topics include: Data Acquisition and Analysis: Electronic Components and Circuits; Electronic Systems; Physical Sciences; Materials; Computer Programs; Mechanics; Machinery; Fabrication Technology; Mathematics and Information Sciences; Life Sciences
Conference on Intelligent Robotics in Field, Factory, Service, and Space (CIRFFSS 1994), volume 1
The AIAA/NASA Conference on Intelligent Robotics in Field, Factory, Service, and Space (CIRFFSS '94) was originally proposed because of the strong belief that America's problems of global economic competitiveness and job creation and preservation can partly be solved by the use of intelligent robotics, which are also required for human space exploration missions. Individual sessions addressed nuclear industry, agile manufacturing, security/building monitoring, on-orbit applications, vision and sensing technologies, situated control and low-level control, robotic systems architecture, environmental restoration and waste management, robotic remanufacturing, and healthcare applications
NASA Tech Briefs, May 1993
Topics include: Advanced Composites and Plastics; Electronic Components and Circuits; Electronic Systems; Physical Sciences; Materials; Computer Programs; Mechanics; Machinery; Fabrication Technology; Mathematics and Information Sciences; Life Sciences