David C. Chu

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A stochastic model is described for the decoder of an optimal<lb>burst-correcting convolutional code. From this model, an upper bound is<lb>obtained for jJ, the error probability per word after decoding. INTRODUCTION<lb>Recent papers [5], [6], use stochastic models to analyze<lb>decoders. We use here similar methods to upperbound the error<lb>probability(More)
A number of multi-hop, wireless, network programming systems have emerged for sensor network retasking but none of these systems support a cryptographically-strong, public-key-based system for source authentication and integrity verification. The traditional technique for authenticating a program binary, namely a digital signature of the program hash, is(More)
The problem with the grid is that it does not currently extend completely to devices, because these devices are not viewed as having sufficient capability to be both clients and services. We design, implement and evaluate Mobile OGSI.NET, which extends an implementation of grid computing, OGSI.NET, to mobile devices. Mobile OGSI.NET addresses the mobile(More)
INTRODUCTION Available assays for quantitation of the Alzheimer's disease (AD) biomarker amyloid-beta 1-42 (Aβ [1-42]) in cerebrospinal fluid demonstrate significant variability and lack of standardization to reference measurement procedures (RMPs). We report analytical performance data for the novel Elecsys β-amyloid (1-42) assay (Roche Diagnostics). (More)
The compact, mobile device, such as the PocketPC, is often regarded as little more than a handy, smaller "portal" by which to access information kept on larger back-end machines such as exchange servers and WWW servers. However, the true value of the device may ultimately result from more sophisticated approaches by which the device can fully recognize and(More)
A number of multi-hop wireless reprogramming systems have emerged for sensor network retasking but none of these systems support a cryptographically-strong, public-key-based system for program authentication or any form of recovery from authenticated, but Byzantine, programs. The traditional techniques for authenticating a program and recovering from(More)
For certain types of digitally generated holographic memories, it is important that the Fourier components to be stored have a constant, or nearly constant, modulus. It is shown that by interlacing two sequences of complex numbers, one a data sequence representing the information to be stored and the second a parity sequence, derivable from the data(More)