The sources of heat generation in vibrothermography

Vibrothermography, or sonic IR, is a nondestructive evaluation technique used to find surface and near surface defects—such as cracks and delaminations—through observations of vibration-induced heat generation. This method has significant interest as an industrial inspection method, however, a lack of understanding of the fundamental physics governing the heat generation process has limited its application despite extensive theoretical, numerical simulation, and experimental work. Significant theoretical and numerical simulation work has been performed, but has yet to be rigorously verified experimentally. This paper presents experimental verification of the sources of heat generation in vibrothermography; specifically friction, plasticity, and viscoelasticity. Specific experimental evidence is presented that verifies each of these heat-generating mechanisms.     

Analysis of CMOS Photodiodes. I. Quantum efficiency

An improved one-dimensional (1-D) analysis of the CMOS photodiode has been derived in which the effect of the substrate, which forms a high-low junction with the epitaxial layer, has been included. The analytical solution was verified with numerical simulations based on parameters extracted from a standard 0.35 /spl mu/m CMOS process. Two empirical parameters are suggested to offset the unavoidable inaccuracies in the extracted parameter values. The derived semiempirical expression exhibits a good agreement with the measured spectral response. In Part II of this paper, a three-dimensional (3-D) analysis of lateral photoresponse in CMOS photodiode arrays is presented along with an empirical modeling method utilizing test linear photodiode arrays.     

Analysis of CMOS Photodiodes. II. Lateral photoresponse

For pt.I see ibid., vol.50, no.5, p.1233-38 (2003). In Part I of this paper, an improved one-dimensional (1-D) analysis and a semiempirical model of quantum efficiency for CMOS photodiode was illustrated. In this part of the paper, the lateral photoresponse in CMOS photodiode arrays is investigated with test linear photodiode arrays and numerical device simulations. It is shown that the surface recombination and mobility degradation along the Si-SiO/sub 2/ interface are important factors in determining the lateral photoresponse of CMOS photodiodes. The limitations of traditional analytical approaches are briefly discussed in this context, and a novel three-dimensional (3-D) analysis of lateral photoresponse is presented. Given the significant dependence of lateral photoresponse on the Si-SiO/sub 2/ interface quality, an empirical characterization method is proposed as a more reliable solution to modeling lateral photoresponse.     

Motion direction estimates from differenced DCT images

A method is presented for estimating motion direction directly from differences in the DCT coefficients of image sequences     

Optimization of ultraviolet laser doping for crystalline silicon solar cells with a novel segmented selective emitter design

This paper reports on the use of ultraviolet laser for forming segmented selective emitters on POCl ₃ n ⁺ –p–p ⁺ solar cells. Laser scan speed, pulse power, and repetition rate are optimized to minimize laser‐induced defects, which are found to enhance recombination and reduce the local open‐circuit voltage. Laser‐doped selective emitters formed by locally driving in additional phosphorous from the diffusion glass are well suited for an etchback process without the need for a mask. In this paper, we show a novel selective emitter design that is segmented instead of continuous, combined with an emitter etchback process gives an efficiency improvement of about 0.3% absolute over a standard industrial type solar cell and 0.2% absolute improvement over a non‐segmented selective emitter solar cell. Copyright © 2012 John Wiley & Sons, Ltd.     

Uptake of Sr2+ and Co2+ into biogenic hydroxyapatite: implications for biomineral ion exchange synthesis

Biomineral hydroxyapatite (Bio-HAp) produced by Serratia sp. has the potential to be a suitable material for the remediation of metal contaminated waters and as a radionuclide waste storage material. Varying the Bio-HAp manufacturing method was found to influence hydroxyapatite (HAp) properties and consequently the uptake of Sr(2+) and Co(2+). All the Bio-HAp tested in this study were more efficient than the commercially available hydroxyapatite (Com-HAp) for Sr(2+) and Co(2+) uptake. For Bio-HAp the uptake for Sr(2+) and Co(2+) ranged from 24 to 39 and 29 to 78 mmol per 100 g, respectively. Whereas, the uptake of Sr(2+) and Co(2+) by Com-HAp ranged from 3 to 11 and 4 to 18 mmol per 100 g, respectively. Properties that increased metal uptake were smaller crystallite size (<40 nm) and higher surface area (>70 m(2) g(-1)). Organic content which influences the structure (e.g., crystallite arrangement, size and surface area) and composition of Bio-HAp was also found to be important in Sr(2+) and Co(2+) uptake. Overall, Bio-HAp shows promise for the remediation of aqueous metal waste especially since Bio-HAp can be synthesized for optimal metal uptake properties.     

Correction to Janes et al. (2009).

Reports an error in "Brain fMRI reactivity to smoking-related images before and during extended smoking abstinence" by Amy C. Janes, Blaise deB. Frederick, Sarah Richardt, Caitlin Burbridge, Emilio Merlo-Pich, Perry F. Renshaw, A. Eden Evins, Maurizio Fava and Marc J. Kaufman (Experimental and Clinical Psychopharmacology, 2009[Dec], Vol 17[6], 365-373). In the article the authors find it necessary to redefine the thresholding procedure used for data analyses, due to problems in the Brain Voyager software. This does not affect the main findings of the paper. (The following abstract of the original article appeared in record 2009-23091-001.) Reactivity to smoking-related cues may play a role in the maintenance of smoking behavior and may change depending on smoking status. Whether smoking cue-related functional MRI (fMRI) reactivity differs between active smoking and extended smoking abstinence states currently is unknown. We used fMRI to measure brain reactivity in response to smoking-related versus neutral images in 13 tobacco-dependent subjects before a smoking cessation attempt and again during extended smoking abstinence (52 ± 11 days) aided by nicotine replacement therapy. Prequit smoking cue induced fMRI activity patterns paralleled those reported in prior smoking cue reactivity fMRI studies. Greater fMRI activity was detected during extended smoking abstinence than during the prequit assessment subcortically in the caudate nucleus and cortically in prefrontal (BA 6, 9, 44, 46), primary somatosensory (BA 1, 2, 3), temporal (BA 22, 41, 42), parietal (BA 7, 40) anterior cingulate (BA 24, 32), and posterior cingulate (BA 31) cortex. These data suggest that during extended smoking abstinence, fMRI reactivity to smoking versus neutral stimuli persists in brain areas involved in attention, somatosensory processing, motor planning, and conditioned cue responding. In some brain regions, fMRI smoking cue reactivity is increased during extended smoking abstinence in comparison to the prequit state, which may contribute to persisting relapse vulnerability. (PsycINFO Database Record (c) 2010 APA, all rights reserved)