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RFC (Recursive Flow Classification) is one of the best packet classification algorithms. However, RFC has moderate to prohibitive high preprocessing time for rule-sets having more than 10K rules. RFC does not provide incremental update. Due to these essential missing features, RFC is used in limited scenarios. This paper attempts to add these essential features in RFC. Our algorithm uses various memory and processing optimizations to speed up RFC preprocessing phase.We provide an algorithm to compute only those CBM (Class Bit Map) intersections for which corresponding value pairs are found in rules. We optimize CBM intersection by using ABV algorithm and min-max rule information. We also propose an optimized algorithm to manage real time incremental updates in RFC. The algorithm modifies only required parts of RFC tables and makes sure that the updated tables have information in correct order. For incremental update, moderate amount of extra memory is required. We tested our algorithm for preprocessing time and incremental update feature. The results indicate that we get moderate improvement in preprocessing time with real time incremental updates in our modified RFC.

The development of artificial reverberation has made considerable progress in recent years. In this research, a unique approach utilizing reciprocal maximum-length sequences and related sequences is taken in generating a natural, spatial sounding reverberation. Additionally, an algorithm to shape and vary spaciousness within the context of an artificially generated reverberation is implemented. Results are verified through experimental measurements and subjective testing methods in a multichannel format. This work sheds light on alternative methods of generating artificial reverberation outside of commercially available systems. As a result, a direct application to room modeling techniques can be drawn with this work. Extensions of this research will comprise of investigations in objective and subjective behaviors of double-sloped energy decays in acoustically coupled spaces. From an educational perspective, outcomes of this research can serve as a foundation in ear-training for acoustics students seeking a broadened understanding of perceived reverberation in varying contexts.

Binaural auralization through proper room-acoustic simulation can produce a realistic listening experience as if the listener were sitting in a room with spatial perception, including enveloping reverberance. Based on analysis of experimentally measured binaural room-acoustic data, this paper discusses an approach to creating artificial but natural-sounding reverberation for binaural rendering that can be employed in simulating such an environment in an efficient way. Approaches to adjusting the spaciousness of enveloping reverberance within the context of artificially generated reverberation are investigated via hearing tests. This paper exploits the excellent pseudorandom properties of maximum-length sequences to generate deterministic and controllable decorrelations between binaural channels for artificial reverberation for room-acoustic simulations with high computational efficiency. To achieve natural-sounding enveloping reverberance in an enclosed space, and thereby an immersive environment, the shapes of both the reverberation energy decays and the spatial characteristics are found to be decisive. This paper discusses systematic hearing test results that support the mentioned finding.

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