An analysis of FPGA-based custom computers for DSP applications

Field programmable gate arrays (FPGAs) can be rapidly reconfigured to provide different digital logic functions. When such FPGA logic circuits are incorporated within a stored-program computer, the result is a machine where the programmer can design both the software and the hardware that will execute that software. This paper first surveys this area of custom computing. It then describes a new custom computing architecture which uses a processing node with three sections: a standard arithmetic chip, static RAM and reconfigurable logic for operand handling. Finally an analysis of the suitability of this new approach for implementation of DSP applications shows it to be worthy of further investigation

Comparing the performance of FPGA-based custom computers with general-purpose computers for DSP applications

When FPGA logic circuits are incorporated within a stored-program computer, the result is a machine where the programmer can design both the software and the hardware that will execute that software. This paper first describes some of the more important custom computers, and their potential weakness as DSP implementation platforms. It then describes a new custom computing architecture which is specifically designed for efficient implementation of DSP algorithms. Finally, it presents a simple performance comparison of a number of DSP implementation alternatives, and concludes that the new custom computing architecture is worthy of further investigation, and that custom computers based only on FPGA execution units show little performance improvement over state-of-the-art workstations

Use of system identification techniques for improving airframe finite element models using test data

A method for using system identification techniques to improve airframe finite element models using test data was developed and demonstrated. The method uses linear sensitivity matrices to relate changes in selected physical parameters to changes in the total system matrices. The values for these physical parameters were determined using constrained optimization with singular value decomposition. The method was confirmed using both simple and complex finite element models for which pseudo-experimental data was synthesized directly from the finite element model. The method was then applied to a real airframe model which incorporated all of the complexities and details of a large finite element model and for which extensive test data was available. The method was shown to work, and the differences between the identified model and the measured results were considered satisfactory

Use of system identification techniques for improving airframe finite element models using test data

A method for using system identification techniques to improve airframe finite element models was developed and demonstrated. The method uses linear sensitivity matrices to relate changes in selected physical parameters to changes in total system matrices. The values for these physical parameters were determined using constrained optimization with singular value decomposition. The method was confirmed using both simple and complex finite element models for which pseudo-experimental data was synthesized directly from the finite element model. The method was then applied to a real airframe model which incorporated all the complexities and details of a large finite element model and for which extensive test data was available. The method was shown to work, and the differences between the identified model and the measured results were considered satisfactory

Non-Resident Alien Investment Activity In Iowa Farmland: A Preliminary Anaylsis

The issue of non-resident alien investment in U.S. business and agriculture has recently attracted the attention of numerous groups at the local, state, and national level. Public discussion and concern on this issue are based largely upon hearsay evidence and incomplete information. A comprehensive source of data or general picture of foreign investment in U.S. agriculture does not exist. Not only are the number of cases and characteristics (type of land, motivations of the investor, the intermediary channels, etc.) of actual investment activity unknown, but the nature and incidence of inquiries are equally unclear..

Culling as an Exploratory Field Technique to Reduce Overall Mortality During a Pasturella Spp. Outbreak in a Montana Bighorn Sheep Population

Several herds of Rocky Mountain bighorn sheep (Ovis Canadensis) in the United States and Canada have experienced all-age die-offs during outbreaks of Pasturella spp. Induced pneumonia. Isolating triggers and remedies for these die-offs remains elusive. Montana Fish, Wildlife and Parks used the statewide Draft Sheep Conservation Strategy as a guide in establishing a field culling-mobile laboratory-media response to a pneumonia/complex outbreak in the East Fork Bitterroot bighorn sheep herd. Montana Fish, Wildlife and Parks employees along with volunteers from the Ravalli County Fish and Wildlife Association, Wild Sheep Foundation and the USDA Forest Service culled 76 sheep from a herd numbering at least 187 animals according to spring 2009 aerial observations. Field personnel discovered six recent bighorn sheep carcasses when culling efforts began in late November. Field personnel discovered one additional bighorn carcass during the three-month culling process. Lab experts conducting onsite necropsies observed evidence of infection in 73 (96%) of the culled sheep. State biologists observed 93 bighorns on this winter range during a cursory aerial survey conducted on 28 December 2009. Preliminary observations from comparing results of sheep selected for culling to field necropsies suggest field personnel detect infected sheep with a high degree of accuracy. We suggest that this technique prevented additional mortalities directly related to pneumonia

Pneumonia Outbreak in Bighorn Sheep in the East Fork of the Bitterroot: A Summary of Pathology and Laboratory Findings

A bighorn sheep (Ovis Canadensis) pneumonia outbreak began in the East Fork of the Bitterroot River drainage in late November 2009. The decision to cull apparently sick animals provided the unique opportunity to collect fresh, high quality biological samples for diagnostic testing. It is our hope that information gained from this outbreak will contribute to an understanding of bighorn sheep pneumonia outbreaks in western states. The Montana Fish, Wildlife, and Parks wildlife laboratory performed full necropsies on many of the bighorn sheep that died or were culled during this outbreak. Body condition score and severity of lung lesions was noted. A fresh blood sample and fecal sample was collected, and the pharynx and ear canal were swabbed. Lung, tracheobronchial lymph node, and liver samples were also collected. Field personnel collected fresh tissue samples from culled sheep that could not be removed from the field for necropsy. Tissues and swabs were submitted to Washington Animal Disease Diagnostic Laboratory (WADDL) for aerobic and Mycoplasma culture. Serum and fecal samples were submitted to the Montana Department of Livestock laboratory in Bozeman. In this presentation we will describe the gross pathology of the pneumonia outbreak, summarize all laboratory findings, and describe similarities and differences when compared to other bighorn sheep pneumonia outbreaks within Montana and in other western states