131 research outputs found

    Feasibility study for a numerical aerodynamic simulation facility. Volume 1

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    A Numerical Aerodynamic Simulation Facility (NASF) was designed for the simulation of fluid flow around three-dimensional bodies, both in wind tunnel environments and in free space. The application of numerical simulation to this field of endeavor promised to yield economies in aerodynamic and aircraft body designs. A model for a NASF/FMP (Flow Model Processor) ensemble using a possible approach to meeting NASF goals is presented. The computer hardware and software are presented, along with the entire design and performance analysis and evaluation

    The design and use of a digital radio telemetry system for measuring internal combustion engine piston parameters.

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    During the course of this project, a digital radio telemetry system has been designed and shown to be capable of measuring parameters from the piston of an internal combustion engine, under load. The impetus for the work stems from the need to sample the appropriate data required for oil degradation analysis and the unavailability of system to perform such sampling. The prototype system was designed for installation within a small Norton Villiers C-30 industrial engine. This choice of engine presented significant design challenges due to the small size of the engine (components and construction) and the crankcase environment. These challenges were manifest in the choice of carrier frequency, antenna size and location, modulation scheme, data encoding scheme, signal attenuation, error checking and correction, choice of components, manufacturing techniques and physical mounting to reciprocating parts. In order to overcome these challenges detailed analysis of the radio frequency spectrum was undertaken in order to minimise attenuation from mechanisms such as, absorption, reflection, motion, spatial arrangement and noise. Another aspect of the project concerned the development of a flexible modus operandi in order to facilitate a number of sampling regimes. In order to achieve such flexibility a two-way communication protocol was implemented enabling the sampling system to be programmed into a particular mode of operation, while in use. Additionally the system was designed to accommodate the range of signals output from most transducer devices. The sampling capabilities of the prototype system were extended by enabling the system to support multiple transducers providing a mixture of output signals; for example both analogue and digital signals have been sampled. Additionally, a facility to sample data in response to triggering stimuli has been tested; specifically a sampling trigger may be derived from the motion of the piston via an accelerometer. Ancillary components, such as interface hardware and software, have been developed which are suitable for the recording of data accessed by the system. This work has demonstrated that multi-transducer, mixed signal monitoring of piston parameters, (such as temperature, acceleration etc.) using a two-way, programmable, digital radio frequency telemetry system is not only possible but provides a means for more advanced instrumentation

    Mission-Critical Communications from LMR to 5G: a Technology Assessment approach for Smart City scenarios

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    Radiocommunication networks are one of the main support tools of agencies that carry out actions in Public Protection & Disaster Relief (PPDR), and it is necessary to update these communications technologies from narrowband to broadband and integrated to information technologies to have an effective action before society. Understanding that this problem includes, besides the technical aspects, issues related to the social context to which these systems are inserted, this study aims to construct scenarios, using several sources of information, that helps the managers of the PPDR agencies in the technological decisionmaking process of the Digital Transformation of Mission-Critical Communication considering Smart City scenarios, guided by the methods and approaches of Technological Assessment (TA).As redes de radiocomunicações são uma das principais ferramentas de apoio dos órgãos que realizam ações de Proteção Pública e Socorro em desastres, sendo necessário atualizar essas tecnologias de comunicação de banda estreita para banda larga, e integra- las às tecnologias de informação, para se ter uma atuação efetiva perante a sociedade . Entendendo que esse problema inclui, além dos aspectos técnicos, questões relacionadas ao contexto social ao qual esses sistemas estão inseridos, este estudo tem por objetivo a construção de cenários, utilizando diversas fontes de informação que auxiliem os gestores destas agências na tomada de decisão tecnológica que envolve a transformação digital da Comunicação de Missão Crítica considerando cenários de Cidades Inteligentes, guiado pelos métodos e abordagens de Avaliação Tecnológica (TA)

    Proceedings of 31st Annual ARCOM Conference, vol 2

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    COBE's search for structure in the Big Bang

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    The launch of Cosmic Background Explorer (COBE) and the definition of Earth Observing System (EOS) are two of the major events at NASA-Goddard. The three experiments contained in COBE (Differential Microwave Radiometer (DMR), Far Infrared Absolute Spectrophotometer (FIRAS), and Diffuse Infrared Background Experiment (DIRBE)) are very important in measuring the big bang. DMR measures the isotropy of the cosmic background (direction of the radiation). FIRAS looks at the spectrum over the whole sky, searching for deviations, and DIRBE operates in the infrared part of the spectrum gathering evidence of the earliest galaxy formation. By special techniques, the radiation coming from the solar system will be distinguished from that of extragalactic origin. Unique graphics will be used to represent the temperature of the emitting material. A cosmic event will be modeled of such importance that it will affect cosmological theory for generations to come. EOS will monitor changes in the Earth's geophysics during a whole solar color cycle

    NASA Tech Briefs, October 2002

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    Topics include: a technology focus on sensors, electronic components and systems, software, materials, materials, mechanics, manufacturing, physical sciences, information sciences, book and reports, motion control and a special section of Photonics Tech Briefs

    High-level automation of custom hardware design for high-performance computing

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    This dissertation focuses on efficient generation of custom processors from high-level language descriptions. Our work exploits compiler-based optimizations and transformations in tandem with high-level synthesis (HLS) to build high-performance custom processors. The goal is to offer a common multiplatform high-abstraction programming interface for heterogeneous compute systems where the benefits of custom reconfigurable (or fixed) processors can be exploited by the application developers. The research presented in this dissertation supports the following thesis: In an increasingly heterogeneous compute environment it is important to leverage the compute capabilities of each heterogeneous processor efficiently. In the case of FPGA and ASIC accelerators this can be achieved through HLS-based flows that (i) extract parallelism at coarser than basic block granularities, (ii) leverage common high-level parallel programming languages, and (iii) employ high-level source-to-source transformations to generate high-throughput custom processors. First, we propose a novel HLS flow that extracts instruction level parallelism beyond the boundary of basic blocks from C code. Subsequently, we describe FCUDA, an HLS-based framework for mapping fine-grained and coarse-grained parallelism from parallel CUDA kernels onto spatial parallelism. FCUDA provides a common programming model for acceleration on heterogeneous devices (i.e. GPUs and FPGAs). Moreover, the FCUDA framework balances multilevel granularity parallelism synthesis using efficient techniques that leverage fast and accurate estimation models (i.e. do not rely on lengthy physical implementation tools). Finally, we describe an advanced source-to-source transformation framework for throughput-driven parallelism synthesis (TDPS), which appropriately restructures CUDA kernel code to maximize throughput on FPGA devices. We have integrated the TDPS framework into the FCUDA flow to enable automatic performance porting of CUDA kernels designed for the GPU architecture onto the FPGA architecture
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