Approximated algorithms for clustering large-scale document collection are proposed and evaluated under the context of cluster-based document retrieval (i.e., associative document search). These algorithms use a precise clustering algorithm as a subroutine to construct a strati ed structure of cluster trees. An experiment showed that more than 100 times speedup in cpu time was gained at best. T...

In this work we use metaheuristic search to improve Google’s Guava library, finding a semantically equivalent version of com.google. common.collect.ImmutableMultimap with reduced energy consumption. Semantics-preserving transformations are found in the source code, using the principle of subtype polymorphism. We introduce a new tool, Opacitor, to deterministically measure the energy consumption...

The block cipher DESX is de ned by DESXk:k1:k2(x) = k2 DESk(k1 x), where denotes bitwise exclusive-or. This construction was rst suggested by Ron Rivest as a computationally-cheap way to protect DES against exhaustive key-search attacks. This paper proves, in a formal model, that the DESX construction is sound. We show that, when F is an idealized block cipher, FXk:k1:k2(x) = k2 Fk(k1 x) is sub...

This paper describes a method for identification of the informative variables in the information system with discrete decision variables. It is targeted specifically towards discovery of the variables that are non-informative when considered alone, but are informative when the synergistic interactions between multiple variables are considered. To this end, the mutual entropy of all possible k-t...

Abstract. We analyze the cost used by a naive exhaustive search algorithm for finding a maximum independent set in random graphs under the usual Gn;p-model where each possible edge appears independently with the same probability p. The expected cost turns out to be of the less common asymptotic order n log , which we explore from several different perspectives. Also we collect many instances wh...

Swarms of mobile robots can be tasked with searching a geographic region for targets of interest, such as buried land mines. We assume that the individual robots are equipped with sensors tuned to the targets of interest, that these sensors have limited range, and that the robots can communicate with one another to enable cooperation. How can a swarm of cooperating sensate robots efficiently se...

CpG islands are genome subsequences with an unexpectedly high number of CG di-nucleotides. They are typically identified using filtering criteria (e.g., G+C% expected vs. observed CpG ratio and length) and are computed using sliding window methods. Most such studies illusively assume an exhaustive search of CpG islands are achieved on the genome sequence of interest. We devise a Lexis diagram a...

High-throughput in vitro methods have been extensively applied to identify linear information that encodes peptide recognition. However, these methods are limited in number of peptides, sequence variation, and length of peptides that can be explored, and often produce solutions that are not found in the cell. Despite the large number of methods developed to attempt addressing these issues, the ...