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Quantum Search in Hilbert Space

A large database would be searched in one quantum computing operation. A proposed quantum-computing algorithm would perform a search for an item of information in a database stored in a Hilbert-space memory structure. The algorithm is intended to make it possible to search relatively quickly through a large database under conditions in which available computing resources would otherwise be considered inadequate to perform such a task.

Posted in: Information Sciences, Briefs, TSP

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Wavelet-Based Real-Time Diagnosis of Complex Systems

Changes in hardware and software can be simultaneously examined for signs of loss of control. A new method of robust, autonomous real-time diagnosis of a time-varying complex system (e.g., a spacecraft, an advanced aircraft, or a process-control system) is presented here. It is based upon the characterization and comparison of (1) the execution of software, as reported by discrete data, and (2) data from sensors that monitor the physical state of the system, such as performance sensors or similar quantitative time-varying measurements. By taking account of the relationship between execution of, and the responses to, software commands, this method satisfies a key requirement for robust autonomous diagnosis, namely, ensuring that control is maintained and followed.

Posted in: Information Sciences, Briefs, TSP

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Runge-Kutta Circular-Advection-Problem Solver

Release 3.0 of the Multi-Stage Runge-Kutta Circular Advection Solver is a computer program that solves the circular-advection problem by use of a general m-stage Runge-Kutta scheme (for m = 1, 2, and 4) on a Cartesian (x,y) grid with optimized coefficients. [The circular-advection problem, ¶u/¶t = (-y,x) × grad(u) is a classical model of convective phenomena suitable for studying the behaviors of algorithms.] The spatial discretization in this software is that of a cell-centered upwind finite-volume formulation. The software is presented as an extensible object-oriented class library arranged so that the components of the Runge-Kutta algorithm can be instantiated arbitrarily from within another computer program. The software includes a complete library wrapper that enables launching of the rest of the software from a command line by use of consistent UNIX-style filter conventions. The source code was developed by use of the Extreme Programming (also known, variously, as "eXtreme Programming" and "XP") methodology, and as such is self-revealing, modular, compact, extendable, and customizable. A unique feature of this program is a provision for comprehensive automated testing. All library classes are bundled with complete verification tests, both documenting the feature behavior and enabling extension by end users. Developers have instant feedback from the automated tests if their extensions conflict with the existing code base. Further, a full set of automated validation tests is included to prove various numerical definitions such as positivity or order property of the solver.

Posted in: Software, Briefs

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Software for Mobile Data-Communication Networks

Mobile Router is operating system code residing in a network router allowing the router to provide mobile-ipv4 functionality for any attached nodes. Mobile Router enables the entire network to roam. It is no longer necessary for every node in the network to run mobile Internet Protocol (IP) software because Mobile Router provides this function. In addition, Mobile Router eliminates the need to reconfigure a router as it moves from one network to another network, even across network domains. For example, Mobile Router enables communication with aircraft via the lnternet and/or intranets. Information as weather data, air-traffic control messages, voice communications, and images could be transmitted to aircraft easily and inexpensively by use of Internet protocols. As another example, data-communication nodes running Mobile Router could be incorporated into ambulances to provide real-time data communications with hospitals and medical experts. Commercial applications could include the provision of mobile Internet connections for cargo and cruise ships, tour buses, passenger aircraft, and automobiles.

Posted in: Software, Briefs, TSP

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Software for Onboard Autonomy of a Three-Spacecraft Mission

A system of software has been designed to enable autonomous operations of the three University-built miniature spacecraft of the Three Corner Sat mission, scheduled for launch in 2003. The main software subsystems and their functions are the following:

Posted in: Software, Briefs, TSP

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ICAN/JAVA: Integrated Composite Analyzer Recoded in Java

The Integrated Composite Analyzer (ICAN) computer program, originally written in the FORTRAN language, has been completely recoded in Java to make it more widely usable. Whereas the original ICAN could be executed on only a limited number of platforms, ICAN/JAVA is compatible with almost all computers and operating systems. Moreover, whereas the original ICAN was applicable to only polymer-based composite materials containing circular fibers, ICAN/JAVA is applicable to diverse composites, including those that contain metal matrices, ceramic matrices, noncircular fibers, and/or particulate reinforcements. ICAN/JAVA can be used to simulate many aspects of the behavior and properties of a composite material and its constituent materials, including vibration-damping and electrical properties. The code includes provisions for three-way substructuring of fiber, interphase, and matrix constituents. Graphical output and telescoping of scale are available. The code includes an on-line user's manual. The Java Runtime Environment software, which can be downloaded free of charge for most platforms, is necessary for execution of ICAN/JAVA.

Posted in: Software, Briefs, TSP

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Software for Multidisciplinary Analysis With Parallelization

HiMAP is an advanced, portable software system that implements highly modular, parallel computation of the possibly nonlinear, coupled behaviors of aeroelastic and other complex systems that comprise subsystems, each of which is modeled by use of software formulated within a separate technological discipline (e.g., fluid dynamics, structural dynamics, and controls). HiMAP is designed to be executed on massively parallel processors (MPPs) and workstation clusters based on a multiple-instruction, multiple-data architecture. Software for solving the differential equations of the fluids discipline (the Navier-Stokes equations) is parallelized according to a zonal approach; that of the structures discipline is parallelized according to a substructures approach. Computations within each discipline are spread across processors by use of a standard message-passing interface (MPI) for interprocessor communications. Computations that involve exchange of information among disciplines are parallelized by use of MPIAPI — a utility software library that flexibly allocates a group of processors and enables communication between processors within the same group or in different groups. Additional parallelization for multiple-parameter cases is implemented by use of a script software subsystem. The combined effect of the three levels of parallelization is an almost linear scaleability for multiple concurrent analyses performed efficiently on MPPs.

Posted in: Software, Briefs, TSP

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