Goddard Visiting Scientist Program for the Space and Earth Sciences Directorate

Progress reports of the Visiting Scientist Program covering the period from 1 Jul. - 30 Sep. 1992 are included. Topics covered include space science and earth science. Other topics covered include cosmic rays, magnetic clouds, solar wind, satellite data, high resolution radiometer, and microwave scattering

SIMD Architectures for Radar Signal Processing and Artificial Neural Networks

The thesis is about computer architectures specially tuned to an application area. This means that the work spans the area from implementation technology via processor and computer system organization to the applications themselves. The work reported here is in the area of embedded high performance computing, near the area of application specific hardware. The thread throughout the thesis is how to design computers to suit a specific application area, while maintaining as much computing performance, programmability, scalability and flexibility as possible. The idea is that the multiple SIMD computing model can be a flexible and reasonably scalable concept for the high end applications considered. To test this hypothesis the approach taken is to use application examples, algorithm analysis and implementation experiments to derive suitable computing modules. These modules are then evaluated according to scalability, generality, efficiency, and implementation aspects. The application areas are artificial neural network computing and signal processing in phased array radar. For the artificial neural network computing a multiple SIMD architecture is suggested and artificial neural network algorithms are mapped onto a typical such module. Implementation aspects are discussed and the design of a prototype is shown. Then the use of artificial neural networks in an industrial real-time application is presented. The artificial neural networks are used to extract information from noisy and non-linear signals in combustion engines. It is shown that the neural networks are feasible, and close to optimal, in this application. In the area of signal processing for phased array radar, two application examples are analyzed and architectures suitable for the these are derived. An intermodule communication for implementation on a fiber-optic network is evaluated in a radar application. Then implementation issues for the processing modules are considered and discussed. This is done in the light of instruction statistics gathered from the application examples. Finally, the results are combined and the VEGA architecture is described and motivated. In the thesis it is shown that the modular, multiple SIMD model can be efficiently used in both signal processing for phased array radar and artificial neural network computing. Furthermore, a conclusion drawn is that the linear array SIMD module with broadcast and ring communication is enough for many popular neural network models. It is also concluded that the moderately parallel MIMD machine with moderately parallel SIMD computing modules is a feasible architecture for signal processing in phased array radar

SIMD Architectures for Radar Signal Processing and Artificial Neural Networks

The thesis is about computer architectures specially tuned to an application area. This means that the work spans the area from implementation technology via processor and computer system organization to the applications themselves. The work reported here is in the area of embedded high performance computing, near the area of application specific hardware. The thread throughout the thesis is how to design computers to suit a specific application area, while maintaining as much computing performance, programmability, scalability and flexibility as possible. The idea is that the multiple SIMD computing model can be a flexible and reasonably scalable concept for the high end applications considered. To test this hypothesis the approach taken is to use application examples, algorithm analysis and implementation experiments to derive suitable computing modules. These modules are then evaluated according to scalability, generality, efficiency, and implementation aspects. The application areas are artificial neural network computing and signal processing in phased array radar. For the artificial neural network computing a multiple SIMD architecture is suggested and artificial neural network algorithms are mapped onto a typical such module. Implementation aspects are discussed and the design of a prototype is shown. Then the use of artificial neural networks in an industrial real-time application is presented. The artificial neural networks are used to extract information from noisy and non-linear signals in combustion engines. It is shown that the neural networks are feasible, and close to optimal, in this application. In the area of signal processing for phased array radar, two application examples are analyzed and architectures suitable for the these are derived. An intermodule communication for implementation on a fiber-optic network is evaluated in a radar application. Then implementation issues for the processing modules are considered and discussed. This is done in the light of instruction statistics gathered from the application examples. Finally, the results are combined and the VEGA architecture is described and motivated. In the thesis it is shown that the modular, multiple SIMD model can be efficiently used in both signal processing for phased array radar and artificial neural network computing. Furthermore, a conclusion drawn is that the linear array SIMD module with broadcast and ring communication is enough for many popular neural network models. It is also concluded that the moderately parallel MIMD machine with moderately parallel SIMD computing modules is a feasible architecture for signal processing in phased array radar

Technology for large space systems: A bibliography with indexes (supplement 22)

This bibliography lists 1077 reports, articles, and other documents introduced into the NASA Scientific and Technical Information System between July 1, 1989 and December 31, 1989. Its purpose is to provide helpful information to the researcher or manager engaged in the development of technologies related to large space systems. Subject areas include mission and program definition, design techniques, structural and thermal analysis, structural dynamics and control systems, electronics, advanced materials, assembly concepts, and propulsion

Space station systems: A bibliography with indexes (supplement 10)

This bibliography lists 1,422 reports, articles, and other documents introduced into the NASA scientific and technical information system between July 1, 1989 and December 31, 1989. Its purpose is to provide helpful information to researchers, designers and managers engaged in Space Station technology development and mission design. Coverage includes documents that define major systems and subsystems related to structures and dynamic control, electronics and power supplies, propulsion, and payload integration. In addition, orbital construction methods, servicing and support requirements, procedures and operations, and missions for the current and future Space Station are included

Proceedings of the ECCOMAS Thematic Conference on Multibody Dynamics 2015

This volume contains the full papers accepted for presentation at the ECCOMAS Thematic Conference on Multibody Dynamics 2015 held in the Barcelona School of Industrial Engineering, Universitat Politècnica de Catalunya, on June 29 - July 2, 2015. The ECCOMAS Thematic Conference on Multibody Dynamics is an international meeting held once every two years in a European country. Continuing the very successful series of past conferences that have been organized in Lisbon (2003), Madrid (2005), Milan (2007), Warsaw (2009), Brussels (2011) and Zagreb (2013); this edition will once again serve as a meeting point for the international researchers, scientists and experts from academia, research laboratories and industry working in the area of multibody dynamics. Applications are related to many fields of contemporary engineering, such as vehicle and railway systems, aeronautical and space vehicles, robotic manipulators, mechatronic and autonomous systems, smart structures, biomechanical systems and nanotechnologies. The topics of the conference include, but are not restricted to: ● Formulations and Numerical Methods ● Efficient Methods and Real-Time Applications ● Flexible Multibody Dynamics ● Contact Dynamics and Constraints ● Multiphysics and Coupled Problems ● Control and Optimization ● Software Development and Computer Technology ● Aerospace and Maritime Applications ● Biomechanics ● Railroad Vehicle Dynamics ● Road Vehicle Dynamics ● Robotics ● Benchmark ProblemsPostprint (published version