10,088 research outputs found

    A C++-embedded Domain-Specific Language for programming the MORA soft processor array

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    MORA is a novel platform for high-level FPGA programming of streaming vector and matrix operations, aimed at multimedia applications. It consists of soft array of pipelined low-complexity SIMD processors-in-memory (PIM). We present a Domain-Specific Language (DSL) for high-level programming of the MORA soft processor array. The DSL is embedded in C++, providing designers with a familiar language framework and the ability to compile designs using a standard compiler for functional testing before generating the FPGA bitstream using the MORA toolchain. The paper discusses the MORA-C++ DSL and the compilation route into the assembly for the MORA machine and provides examples to illustrate the programming model and performance

    Adaptive structured parallelism for computational grids

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    Algorithmic skeletons abstract commonly-used patterns of parallel computation, communication, and interaction. They provide top-down design composition and control inheritance throughout the whole structure. Parallel programs are expressed by interweaving parameterised skeletons analogously to the way sequential structured programs are constructed. This design paradigm, known as structured parallelism, provides a high-level parallel programming method which allows the abstract description of programs and fosters portability. That is to say, structured parallelism requires the description of the algorithm rather than its implementation, providing a clear and consistent meaning across platforms while their associated structure depends on the particular implementation. By decoupling the structure from the meaning of a parallel program, it benefits entirely from any performance improvements in the systems infrastructure

    Advanced manned space flight simulation and training: An investigation of simulation host computer system concepts

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    The findings of a preliminary investigation by Southwest Research Institute (SwRI) in simulation host computer concepts is presented. It is designed to aid NASA in evaluating simulation technologies for use in spaceflight training. The focus of the investigation is on the next generation of space simulation systems that will be utilized in training personnel for Space Station Freedom operations. SwRI concludes that NASA should pursue a distributed simulation host computer system architecture for the Space Station Training Facility (SSTF) rather than a centralized mainframe based arrangement. A distributed system offers many advantages and is seen by SwRI as the only architecture that will allow NASA to achieve established functional goals and operational objectives over the life of the Space Station Freedom program. Several distributed, parallel computing systems are available today that offer real-time capabilities for time critical, man-in-the-loop simulation. These systems are flexible in terms of connectivity and configurability, and are easily scaled to meet increasing demands for more computing power

    ANTENNA FOR WIRELESS UNDERGROUND COMMUNICATION

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    Systems and methods are disclosed for an underground antenna structure for radiating through a dissipative medium, the antenna structure. The antenna structure includes a dielectric substrate, a feeding structure disposed on the substrate, and one or more electrical conductors. The one or more electrical conductors are disposed on the substrate, oriented, and buried within the dissipative medium. The electrical conductors are also adapted to radiate signals at a frequency in half-space adjacent to the dissipative medium. The adaptation includes a beamwidth state for one or more of the electrical conductors based at least in part on the relative permittivity of the dissipative medium

    A Logic-based Approach for Recognizing Textual Entailment Supported by Ontological Background Knowledge

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    We present the architecture and the evaluation of a new system for recognizing textual entailment (RTE). In RTE we want to identify automatically the type of a logical relation between two input texts. In particular, we are interested in proving the existence of an entailment between them. We conceive our system as a modular environment allowing for a high-coverage syntactic and semantic text analysis combined with logical inference. For the syntactic and semantic analysis we combine a deep semantic analysis with a shallow one supported by statistical models in order to increase the quality and the accuracy of results. For RTE we use logical inference of first-order employing model-theoretic techniques and automated reasoning tools. The inference is supported with problem-relevant background knowledge extracted automatically and on demand from external sources like, e.g., WordNet, YAGO, and OpenCyc, or other, more experimental sources with, e.g., manually defined presupposition resolutions, or with axiomatized general and common sense knowledge. The results show that fine-grained and consistent knowledge coming from diverse sources is a necessary condition determining the correctness and traceability of results.Comment: 25 pages, 10 figure

    A Flexible Object Oriented Spacecraft Operating System (FOS)

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    Satellite Operating Software has traditionally been highly specialized custom software which operates one satellite according to deterministic rules. Software changes are usually accomplished with a complete reload from the ground, and performing patches require explicit knowledge of memory maps, variable locations, etc. and can often result in long term satellite down times. As computer, sensor and communication technology increases, more and more of the computing, routing and decision functions of small satellite systems are occurring onboard, and a need exists for adaptable flexible software. The object oriented approach to satellite operating systems provides a malleable system, resilient to failure, distributable across multiple satellites and easily adaptable to other applications. The Operating System acts as a switch for the distribution and execution of messages whether a command, code or data. Even operating system functions can only be executed by sending a message internally. These technique’s provide for a safe system and simplified software maintenance. Since software code is broken into objects, the particular application can be distributed amongst one or more processors, satellites, ground stations or remote terminals. This allows for multi-processor based communication load balancing algorithms, dynamic fail-over capability and compute bound resource sharing. Since no explicit hardware knowledge is required by the flight application code, most objects can be reused for other satellite applications. Such systems can be implemented on small satellites using current processor technology

    Slovenian Virtual Gallery on the Internet

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    The Slovenian Virtual Gallery (SVG) is a World Wide Web based multimedia collection of pictures, text, clickable-maps and video clips presenting Slovenian fine art from the gothic period up to the present days. Part of SVG is a virtual gallery space where pictures hang on the walls while another part is devoted to current exhibitions of selected Slovenian art galleries. The first version of this application was developed in the first half of 1995. It was based on a file system for storing all the data and custom developed software for search, automatic generation of HTML documents, scaling of pictures and remote management of the system. Due to the fast development of Web related tools a new version of SVG was developed in 1997 based on object-oriented relational database server technology. Both implementations are presented and compared in this article with issues related to the transion between the two versions. At the end, we will also discuss some extensions to SVG. We will present the GUI (Graphical User Interface) developed specially for presentation of current exhibitions over the Web which is based on GlobalView panoramic navigation extension to developed Internet Video Server (IVS). And since SVG operates with a lot of image data, we will confront with the problem of Image Content Retrieval
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