Workshop proceedings: Information Systems for Space Astrophysics in the 21st Century, volume 1

The Astrophysical Information Systems Workshop was one of the three Integrated Technology Planning workshops. Its objectives were to develop an understanding of future mission requirements for information systems, the potential role of technology in meeting these requirements, and the areas in which NASA investment might have the greatest impact. Workshop participants were briefed on the astrophysical mission set with an emphasis on those missions that drive information systems technology, the existing NASA space-science operations infrastructure, and the ongoing and planned NASA information systems technology programs. Program plans and recommendations were prepared in five technical areas: Mission Planning and Operations; Space-Borne Data Processing; Space-to-Earth Communications; Science Data Systems; and Data Analysis, Integration, and Visualization

Army-NASA aircrew/aircraft integration program (A3I) software detailed design document, phase 3

The capabilities and design approach of the MIDAS (Man-machine Integration Design and Analysis System) computer-aided engineering (CAE) workstation under development by the Army-NASA Aircrew/Aircraft Integration Program is detailed. This workstation uses graphic, symbolic, and numeric prototyping tools and human performance models as part of an integrated design/analysis environment for crewstation human engineering. Developed incrementally, the requirements and design for Phase 3 (Dec. 1987 to Jun. 1989) are described. Software tools/models developed or significantly modified during this phase included: an interactive 3-D graphic cockpit design editor; multiple-perspective graphic views to observe simulation scenarios; symbolic methods to model the mission decomposition, equipment functions, pilot tasking and loading, as well as control the simulation; a 3-D dynamic anthropometric model; an intermachine communications package; and a training assessment component. These components were successfully used during Phase 3 to demonstrate the complex interactions and human engineering findings involved with a proposed cockpit communications design change in a simulated AH-64A Apache helicopter/mission that maps to empirical data from a similar study and AH-1 Cobra flight test

Mission-based reliability prediction in component-based systems

This paper develops a framework for the extraction of a reliability block diagram in component-based systems for reliability prediction with respect to specific missions. A mission is defined as a composition of several high-level functions occurring at different stages and for a specific time during the mission. The high-level functions are decomposed into lower-level functions, which are then mapped to their corresponding components or component assemblies. The reliability block diagram is obtained using functional decomposition and function-component association. Using the reliability block diagram and the reliability information on the components such as failure rates, the reliability of the system carrying out a mission can be estimated. The reliability block diagram is evaluated by converting it into a logic (Boolean) expression. A modeling language created using the Generic Modeling Environment (GME) platform is used, which enables modeling of a system and captures the functional decomposition and function-component association in the system. This framework also allows for real-time monitoring of the system performance where the reliability of the mission can be computed over time as the mission progresses. The uncertainties in the failure rates and operational time of each high-level function are also considered which are quantified through probability distributions using the Bayesian framework. The dependence between failures of components are also considered and are quantified through a Bayesian network (BN). Other quantities of interest such as mission feasibility and function availability can also be assessed using this framework. Mission feasibility analysis determines if the mission can be accomplished given the current state of components in the system, and function availability provides information whether the function will be available in the future given the current state of the system. The proposed methodology is demonstrated using a radio-controlled (RC) car to carry out a simple surveillance mission

On the engineering of crucial software

The various aspects of the conventional software development cycle are examined. This cycle was the basis of the augmented approach contained in the original grant proposal. This cycle was found inadequate for crucial software development, and the justification for this opinion is presented. Several possible enhancements to the conventional software cycle are discussed. Software fault tolerance, a possible enhancement of major importance, is discussed separately. Formal verification using mathematical proof is considered. Automatic programming is a radical alternative to the conventional cycle and is discussed. Recommendations for a comprehensive approach are presented, and various experiments which could be conducted in AIRLAB are described

Parallel Multi-core Verilog HDL Simulation

In the era of multi-core computing, the push for creating true parallel applications that can run on individual CPUs is on the rise. Application of parallel discrete event simulation (PDES) to hardware design verification looks promising, given the complexity of today’s hardware designs. Unfortunately, the challenges imposed by lack of inherent parallelism, suboptimal design partitioning, synchronization and communication overhead, and load balancing, render this approach largely ineffective. This thesis presents three techniques for accelerating simulation at three levels of abstraction namely, RTL, functional gate-level (zero-delay) and gate-level timing. We review contemporary solutions and then propose new ways of speeding up simulation at the three levels of abstraction. We demonstrate the effectiveness of the proposed approaches on several industrial hardware designs

NASA Tech Briefs, January 1999

Topics include: special coverage sections on sensors and data acquisition and sections on electronic components and circuits, electronic software, materials, mechanics, bio-medical physical sciences, book and reports, and a special section of Photonics Tech Briefs

The Automatist Storytelling System : putting the editor's knowledge in software

Thesis (M.S.)--Massachusetts Institute of Technology, Program in Media Arts & Sciences, 1996.Includes bibliographical references (p. 75-76).by Michael Luke Murtaugh.M.S

The Apothecary's Tales: a game of language in a language of games

A thesis submitted to the University of Bedfordshire, in partial fulfilment requirements for the degree of Doctor of Philosophy (Creative Writing)The thesis shows how the novel The Apothecary's Tales manipulates narrative frames to create a 'simulachron', an unreliable virtual world, which problematises the reader's conceptions of the past. The novel transgresses the generic rules of 'historical fiction' to create a quality of 'historicity' located in the affect of alterity. This is argued to be a somatic response to peril deferred. The novel seeks to evoke alterity by defamiliarising linguistic norms. It does this principally through the use of 'diachronic polysemia' (lexical 'false friends') and intertexts to syncopate the reader continually between the disparate sensibilities of the 1ih and 21 st centuries. These sensibilities are simulated in the novel by the imbedment of sociolects and 'hypomemes', the tacit thoughtways supposed peculiar to a given milieu. To self-authenticate its fictions, the novel employs the 'parafictive' devices of a testamentary found artifact, an unreliable narrator and editor, plausible sociologuemes (social conventions) and ideologuemes (ideologies that inform behaviour), along with a density of period minutiae putatively grounded in the record. Any truth effects achieved are then ludically subverted by a process of critique in which structural units of the novel systematically parody the other. The novel is patterned in the structure of a nested diptych, of expositions contra posed in a mutual commentary, which extends from the defining templates of plot and episode to the micro levels of morphemes in polysemic wordplay. The tropes of nested framing and repetition of form and syntagm are defined in the thesis, respectively, as encubi/atio and 'emblematic resonance'. It is argued that these tropes, encoded in a fictive discourse that defies closure, provide a simulation of hermetic form that -when mapped upon the aleatory life world -can be productive of aesthetic affect. The agonistic elements of plot and incident in the novel are figured within the tapas of theatre, foregrounded by the duplicitous self-fashioning of the characters, and by the continual metaleptic shifts or 'frame syncopation' of narrative viewpoint, both intra and extra-diegetic. Frame syncopation is used advisedly to dilemmatise significations at both the structural and syntagmatic levels. The thesis contends that such contrived collisions of narrative interpretation may be the dynamic of affectivity in all aesthetic discourse