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Transformation as a Design Process and Runtime Architecture for High Integrity Software

Description: We have discussed two aspects of creating high integrity software that greatly benefit from the availability of transformation technology, which in this case is manifest by the requirement for a sophisticated backtracking parser. First, because of the potential for correctly manipulating programs via small changes, an automated non-procedural transformation system can be a valuable tool for constructing high assurance software. Second, modeling the processing of translating data into information as a, perhaps, context-dependent grammar leads to an efficient, compact implementation. From a practical perspective, the transformation process should begin in the domain language in which a problem is initially expressed. Thus in order for a transformation system to be practical it must be flexible with respect to domain-specific languages. We have argued that transformation applied to specification results in a highly reliable system. We also attempted to briefly demonstrate that transformation technology applied to the runtime environment will result in a safe and secure system. We thus believe that the sophisticated multi-lookahead backtracking parsing technology is central to the task of being in a position to demonstrate the existence of HIS.
Date: April 5, 1999
Creator: Bespalko, S.J. & Winter, V.L.
Partner: UNT Libraries Government Documents Department

Context sensitivity and ambiguity in component-based systems design

Description: Designers of components-based, real-time systems need to guarantee to correctness of soft-ware and its output. Complexity of a system, and thus the propensity for error, is best characterized by the number of states a component can encounter. In many cases, large numbers of states arise where the processing is highly dependent on context. In these cases, states are often missed, leading to errors. The following are proposals for compactly specifying system states which allow the factoring of complex components into a control module and a semantic processing module. Further, the need for methods that allow for the explicit representation of ambiguity and uncertainty in the design of components is discussed. Presented herein are examples of real-world problems which are highly context-sensitive or are inherently ambiguous.
Date: October 1, 1997
Creator: Bespalko, S.J. & Sindt, A.
Partner: UNT Libraries Government Documents Department

Technical and policy issues related to semantically and spatially incompatible geodata

Description: Both the Intelligent Transportation Systems (ITS) and National Information Infrastructure (NU) efforts have ambitious goals that are expected to improve the fundamental infrastructure, commerce, and society of the United States. Achieving these goals will require rapid development and deployment of information compatibility methods through technical and institutional standards. These standards will have to be scaleable and flexible to support new, and as-yet-undiscovered, data. Yet they will also need to accommodate our valuable data reserves. The area of geospatial data, and thus the creation of a National Spatial Data Infrastructure (NSDI), is particularly challenging due to the profoundly different forms, evolutionary histories, and meanings attached to spatial data. We discuss technical issues resulting from the different natures and inaccuracy of existing geodata, and areas where federal policy could lead the way to greater compatibility.
Date: July 1, 1995
Creator: Bespalko, S.J.; Ganter, J.H. & Meter, M.D. Van
Partner: UNT Libraries Government Documents Department

Data and methods for the assessment of the risks associated with the maritime transport of radioactive materials: Results of the SeaRAM program studies. Volume 1 -- Main report

Description: This report describes ship accident event trees, ship collision and ship fire frequencies, representative ships and shipping practices, a model of ship penetration depths during ship collisions, a ship fire spread model, cask to environment release fractions during ship collisions and fires, and illustrative consequence calculations.
Date: May 1, 1998
Creator: Sprung, J.L.; Bespalko, S.J. & Kanipe, F.L.
Partner: UNT Libraries Government Documents Department

Data and methods for the assessment of the risks associated with the maritime transport of radioactive materials: Results of the SeaRAM program studies. Volume 2 -- Appendices

Description: This report describes ship accident event trees, ship collision and ship fire frequencies, representative ships and shipping practices, a model of ship penetration depths during ship collisions, a ship fire spread model, cask to environment release fractions during ship collisions and fires, and illustrative consequence calculations. This report contains the following appendices: Appendix 1 -- Representative Ships and Shipping Practices; Appendix 2 -- Input Data for Minorsky Calculations; Appendix 3 -- Port Ship Speed Distribution; and Appendix 4 -- Cask-to-Environment Release Fractions.
Date: May 1, 1998
Creator: Sprung, J. L.; Bespalko, S. J. & Kanipe, F. L.
Partner: UNT Libraries Government Documents Department

Radiological consequences of ship collisions that might occur in U.S. Ports during the shipment of foreign research reactor spent nuclear fuel to the United States in break-bulk freighters

Description: Accident source terms, source term probabilities, consequences, and risks are developed for ship collisions that might occur in U.S. ports during the shipment of spent fuel from foreign research reactors to the United States in break-bulk freighters.
Date: August 1, 1996
Creator: Sprung, J.L.; Bespalko, S.J.; Massey, C.D.; Yoshimura, R.; Johnson, J.D.; Reardon, P.C. et al.
Partner: UNT Libraries Government Documents Department