APB-1 Consumer Reports Addendum: Beam Noise Predictions for the MVSC Adaptive Beamformer
This report completes the Consumer Reports performance analysis study for the Phase 1 Advanced Processor Build sonar system. It provides a performance comparison between the conventional beamformer and the beam-based minimum variance soft constraint adaptive beamformer processing modules. Comparison was based on a beam noise output metric defined in terms of the beamformer array gain. This provides a more realistic measure of beamformer performance since, unlike the common definition of beam noise based solely on the noise field input to the beamformer, our beam noise metric factors in changes of signal power as the target signal is passed through the beamformer. Our results indicate that performance gain can be realized for the adaptive beamformer for certain scenarios. These gains were most likely to occur at the medium frequencies between 100 and 200 Hz, while significant gain was only occasionally observed at other frequencies. Adaptive beamforming was particularly successful when a clutter signal was present. However, any performance advantage usually begins to disappear as the target signal-to-noise ratio increases above approximately –15 dB.
Array Gain as a Function of SNR for the Beam-based MVSC Adaptive Beamformer
This paper examines the beam-based minimum variance soft constraint beamformer and shows that the beamformer array gain is almost always a function of SNR. The analysis shows that the MVSC array gain is necessarily a nonincreasing function of SNR and, in fact, is either strictly decreasing or constant relative to SNR. This result supplements earlier results of Van Veen and helps explain behavior observed in processed data.
The Bastille: A History of a Symbol of Despotism and Freedom
This book is both an analysis of the Bastille as cultural paradigm and a case study on the history of French political culture. It examines in particular the storming and subsequent fall of the Bastille in Paris on July 14, 1789 and how it came to represent the cornerstone of the French Revolution, becoming a symbol of the repression of the Old Regime. Lusebrink and Reichardt use this semiotic reading of the Bastille to reveal how historical symbols are generated; what these symbols’ functions are in the collective memory of societies; and how they are used by social, political, and ideological groups.

To facilitate the symbolic nature of the investigation, this analysis of the evolving signification of the Bastille moves from the French Revolution to the nineteenth century to contemporary history. The narrative also shifts from France to other cultural arenas, like the modern European colonial sphere, where the overthrow of the Bastille acquired radical new signification in the decolonization period of the 1940s and 1950s. The Bastille demonstrates the potency of the interdisciplinary historical research that has characterized the end of this century, combining quantitative and qualitative approaches, and taking its methodological tools from history, sociology, linguistics, and cultural and literary studies.