Joseph A. O'Sullivan

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An information–theoretic analysis of information hiding is presented in this paper, forming the theoretical basis for design of information–hiding systems. Information hiding is an emerging research area which encompasses applications such as copyright protection for digital media, watermarking, fingerprinting, and steganography. In these applications,(More)
The electrocardiogram (ECG) is an emerging biometric modality that has seen about 13 years of development in peer-reviewed literature, and as such deserves a systematic review and discussion of the associated methods and findings. In this paper, we review most of the techniques that have been applied to the use of the electrocardiogram for biometric(More)
In this paper, we present the results of an analysis of the electrocardiogram (ECG) as a biométrie using a novel short-time frequency method with robust feature selection. Our proposed method incorporates heartbeats from multiple days and fuses information. Single lead ECG signals from a comparatively large sample of 269 subjects that were sampled(More)
Wireless sensor networks often face the critical challenge of sustaining long-term operation on limited battery energy. Coverage maintenance protocols can effectively prolong network lifetime by maintaining sufficient sensing coverage over a region using a small number of active nodes while scheduling the others to sleep. We present a novel distributed(More)
Iterative deblurring methods using the expectation maximization (EM) formulation and the algebraic reconstruction technique (ART), respectively, are adapted for metal artifact reduction in medical computed tomography (CT). In experiments with synthetic noise-free and additive noisy projection data of dental phantoms, it is found that both simultaneous(More)
Proposes a framework for simultaneous detection, tracking, and recognition of objects via data fused from multiple sensors. Complex dynamic scenes are represented via the concatenation of simple rigid templates. The variability of the infinity of pose is accommodated via the actions of matrix Lie groups extending the templates to individual instances. The(More)
In the selection of biometrics for use in a recognition system and in the subsequent design of the system, the predicted performance is a key consideration. The realizations of the biometric signatures or vectors of features extracted from the signatures can be modeled as realizations of random processes. These random processes and the resulting(More)