Power-/energy-efficient BIST schemes for processor data paths

Processor core power is primarily consumed in a data path consisting of high-activity functional modules. We propose low-power/energy BIST schemes for data path architectures built around the most common combinations of multipliers, adders, ALUs, and shifters     

Use of lambda DNA as a marker to assess DNA stability in olive oil during storage

Filtered olive oil samples spiked with three different concentrations of λDNA were stored at 25 °C under a 12 h photoperiod for up to a year. These samples were used for DNA extraction and PCR amplification of λDNA amplicons of 107, 415 and 691 bp length. The amplification signal was gradually decreased with longer storage periods, while the strength of the signal was related to the initial concentration of spiking λDNA particularly during longer storage periods. The 107 bp amplicon was the only one successfully amplified from all the samples, regardless of both concentration of spiking λDNA and storage period. The amplification of 415 and 691 bp amplicons was not successful for samples stored longer than a threshold period of 20 and 10 days, respectively. These results suggest that detection of polymorphic markers requiring DNA templates shorter than 100 bp might have a wider range of applications in DNA fingerprinting of olive oil. In addition, the DNA extracts were tested for the presence of inhibitors in PCR amplification reactions of yeast DNA amplicons. The inhibitory effect of olive DNA extracts was partial and gradually increased with the storage period of the olive oil samples used for the DNA extraction.     

Sensor integration and data fusion

The problem of sensor integration and data fusion is addressed. We consider the problem of combining information from diversified sources in a coherent fashion. We assume that information from various sensors may be available in different forms at the fusion. For example, data from infrared (IR) sensors may be combined with range radar (RR) data and further combined with visual images. In each case, data and information from different sensors are presented in a different format which may not be directly compatible for all sensors. Part of the available information may be in the form of attributes and part in the form of dynamical measurements. A generalized evidence processing theory and an architecture for sensor integration and data fusion that accommodates diversified sources of information are presented. Data (or, more generically, information) fusion may take place at different levels, such as the level of dynamics, the level of attributes, and the level of evidence. The common and different aspects of fusion at the different levels are investigated and several practical examples of real world data fusion problems are discussed.     

Blind Position Location via Geometric Loci Construction

A new position location technique is proposed, using received signal strength measurements, which can be implemented using inexpensive off-the-shelf equipment. The proposed technique is based on geometric loci construction, and overcomes the need for onsite calibration measurements or propagation prediction tools and topographical/architectural plans of the covered area. The proposed algorithm exhibits similar simulated performance compared to a recently proposed positioning technique, but without the need of model calibration. In addition, measurements results are also presented, demonstrating the performance of the algorithm.     

A periodogram-based method for the detection of steady-statevisually evoked potentials

The task of objective perimetry is to scan the visual field and find an answer about the function of the visual system. Flicker-burst stimulation-a physiological sensible combination of transient and steady-state stimulation-is used to generate deterministic sinusoidal responses or visually evoked potentials (VEPs) at the visual cortex, which are derived from the electroencephalogram by a suitable electrode array. Here, the authors develop a new method for the detection of VEPs. Based on the periodogram of a time-series, they test the data for the presence of hidden periodic components, which correspond to steady-state VEPs. The method is applied successfully to real data     

Image reconstruction based on human and monkey cone mosaics

The image reconstruction capacity of the actual foveal cone sampling mosaics of an adult monkey and human is investigated through computer simulations. A retinocortical mapping model in which positions are known and disorder is compensated (DC) has been implemented using classical Whittaker-Kotelnikov-Shannon (WKS) reconstruction theory and a two-dimensional hexagonal tessellation technique that maps the cone lattice onto a perfectly hexagonal grid. The DC model has been compared with a retinocortical mapping model in which cone positions are also known but position disorder is uncompensated (DU) in the reconstruction process. A control model has also been implemented using WKS reconstruction based on sampled data obtained with simulated perfectly hexagonal lattices whose Nyquist limits are equivalent to those of the human and monkey lattices. Quantitative comparisons of these models are based on the RMS error per pixel between the original and reconstructed images. Results of these simulations demonstrate a pronounced superiority of the DC over the DU model. The results of these simulations, which use “biologically correct” sampling lattices, document a potential image reconstruction advantage when foveal cone positions are known.     

Simulation of an industrial computer system—A case study

The purpose of this work was to explain long term variations in computer system performance by developing and using a simple discrete event simulation model. The system studied was an IBM 370/165 (with OS/MVT) used by a major U.S. corporation over the 3 yr period of 1972 through 1974. The model was calibrated and validated against data from the actual system and was successfully used to develop relationships between work load, hardware configuration, and performance. These results were used to establish the cause of major degradations in service levels that had been experienced on the actual system and provide insight into functional dependencies otherwise unobtainable. The study demonstrated that a reasonable match between the behavior of a complex computer system in the real and simulated worlds can be obtained by using straightforward simulation techniques and readily available performance data.