Design and Implementation of High-Performance RNS Wavelet Processors Using Custom IC Technologies

The design of high performance, high precision, real-time digital signal processing (DSP) systems, such as those associated with wavelet signal processing, is a challenging problem. This paper reports on the innovative use of the residue number system (RNS) for implementing high-end wavelet filter banks. The disclosed system uses an enhanced index-transformation defined over Galois fields to efficiently support different wavelet filter instantiations without adding any extra cost or additional look-up tables (LUT). A selection of a small wordwidth modulus set are the keys for attaining low-complexity and high-throughput. An exhaustive comparison against existing two's complement (2C) designs for different custom IC technologies was carried out. Results reveal a performance improvement of up to 100% for high-precision RNS-based systems. These structures demonstrated to be well suited for field programmable logic (FPL) assimilation as well as for CBIC (cell-based integrated circuit) technologies.     

Category effects in temporal visual search.

When subjects identify a target during rapid serial visual presentation (RSVP), they show a reduced ability to detect a subsequent probe stimulus relative to when they ignore the target. The present study demonstrated an effect of target/probe categorical relation upon this probe detection deficit (attentional blink). Experiment 1 used letters for both target and probe, replicating the general methods and results of Raymond, Shapiro, and Arnell (1992). Experiment 2 varied target/probe categorical relation via instructional set: The target was referred to as the letter 'oh', whereas for other subjects it was referred to as the number 'zero.' Treating O as a number attenuated the probe detection deficit. This different-category attenuation was confirmed in Experiment 3 where the target was a letter and the probe was a number. The observed category effect suggests that the probe detection deficit in RSVP may map a time course from spreading intra-category inhibition following temporal target selection. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Individual differences in executive functions are almost entirely genetic in origin.

Recent psychological and neuropsychological research suggests that executive functions--the cognitive control processes that regulate thought and action--are multifaceted and that different types of executive functions are correlated but separable. The present multivariate twin study of 3 executive functions (inhibiting dominant responses, updating working memory representations, and shifting between task sets), measured as latent variables, examined why people vary in these executive control abilities and why these abilities are correlated but separable from a behavioral genetic perspective. Results indicated that executive functions are correlated because they are influenced by a highly heritable (99%) common factor that goes beyond general intelligence or perceptual speed, and they are separable because of additional genetic influences unique to particular executive functions. This combination of general and specific genetic influences places executive functions among the most heritable psychological traits. These results highlight the potential of genetic approaches for uncovering the biological underpinnings of executive functions and suggest a need for examining multiple types of executive functions to distinguish different levels of genetic influences. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Response of a Terminated Transmission Line Excited by a Plane Wave Field for Arbitrary Angles of Incidence

An analysis to determine the response of an impedance-loaded transmission line configuration excited by a plane-polarized electric field of arbitrary spatial orientation has been needed for a long time. The purpose of the present paper is to meet this need by suggesting a method of solution based on the analysis of the simplest of such circuits: an impedance-terminated two-conductor transmission line. The theory is based on the use of the Rayleigh-Carson reciprocity theorem.     

Age analysis of cognitive-behavioral group therapy for chronic pain outpatients.

This study explored the effectiveness, in terms of age of the client, of a 10-week cognitive–behavioral group therapy (stress inoculation training) for chronic pain. A total of 69 outpatients between the ages of 27 and 80 (M?=?52.74 years, SD?=?14.40) with diverse types of chronic pain were assigned randomly to immediate or wait-list-delayed therapy. Self-report measures of pain, activities, coping, and the use of medications and other physical pain control techniques were obtained at baseline, during therapy, and at 1- and 6-month follow-up. Treatment decreased the degree to which pain interfered with activity, increased ability to cope with pain, and decreased use of some medications and other physical treatments. It had little effect on perceived pain intensity. Gains were maintained through 6-month follow-up. Age was unrelated to outcome. Stress inoculation training appears to be an effective method of ameliorating the interference of chronic pain with the daily activities of life for adults of all ages. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Proton-decoupled 31P chemical shift imaging of the human brain in normal volunteers

Proton-decoupled, 31P three-dimensional (3-D) chemical shift imaging (CSI) spectra have been acquired from the entire human brain using a new dual tuned resonator. The resonator operates in quadrature mode to provide improved sensitivity, excellent B1 homogeneity and reduced power deposition at both frequencies. Proton-decoupled and fully NOE enhanced, 31P spectra were acquired from normal volunteers using Waltz-4 proton decoupling with continuous wave bi-level excitation applied through a second radio frequency channel. Well resolved peaks in the phosphomonoester (PME) and phosphodiester regions were obtained from nonlocalized FIDs and spectra localized with 3-D CSI without processing for resolution enhancement. pH measurements made over large regions of the brain using the P(i) resonance show no significant variations (6.9 +/- 0.02) for a single individual. The improved spectral resolution and sensitivity of the PME resonances results in more well defined metabolite images of the PME peak region.     

Discriminability and the contrafreeloading phenomenon.

According to previous reports of the contrafreeloading phenomenon, animals will work for a reward, and sometimes work quite hard, in the presence of the same reward available freely. Results of the present 2 experiments with a total of 21 male Holtzman albino rats suggest that the contrafreeloading data are explainable with a basic learning principle, discriminability, and its accompanying response decrement. For some Ss the change in stimulus conditions with introduction of free water was made more highly discriminable by a change in earned reinforcement conditions. The other Ss remained on the same earned reinforcement conditions under which all the Ss had been trained. Findings demonstrate that the discriminability between the conditions of working and freeloading was a most important factor contributing to the continued responding in the presence of free rewards. (18 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Activity memory and aging: The role of motor retrieval and strategic processing.

Examined the role of retrieval and encoding mechanisms in the magnitude of age differences in the recall of S-performed tasks (SPTs). 80 older (60–79 yrs old) and 80 younger adults (18–26 yrs old) were tested in 1 of 4 conditions by varying modality at both encoding and retrieval. The role of list organization in reducing age differences in SPT recall was also examined. The results suggested that older adults' SPT recall improves when motor processing is enhanced by list organization. Age differences in recall were reduced for an organized list when motor processing occurred during retrieval or encoding, but age differences in recall of an unorganized list remained under most conditions. Discrepant results in the literature concerning the magnitude of age differences in SPT recall could be due in part to differences in list characteristics, such as organization, that have not been fully explored. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Office communications: reshaping our society?

A revolution in office communications technology is about to overtake organizational administrators. This revolution has two sides: one concerned with the production of organizational intelligence and the other with its distribution. The paper suggests that new technology in the office will have a greater impact on society than is currently expected. The older computer technology (large mainframe-based systems) tended to promote ‘centralization’, whereas the new communications technology (videotex, fibre optics) promotes ‘distributed intelligence’. A study of the effect of new technology in one company is examined. Its use influenced organizational structures within the company and altered human interaction patterns. The paper suggests that society needs to rethink the very notion of an organizational system as communications technology advances.