A widely-proposed way to retrofit coal-fired power plants with post-combustion CO2 capture (PCC) is to supply all the electricity and heat required to operate the capture equipment from the existing steam cycle (an ‘integrated retrofit’), at the expense of a reduction in site power output. As an alternative, it is possible to add a gas turbine (GT) plant to maintain, or even increase, the net site power output. The GT can be integrated with the capture plant in various ways to supply all or part of the heat and power required for the capture and compression systems. But there is then the issue of how to capture the CO2 emissions from the added GT plant. In this study a novel retrofit configuration is proposed. The exhaust gas of the GT replaces part of the secondary air for the coal boiler and a common capture system is used for both coal- and natural gas-derived CO2. This new ‘GT flue gas windbox retrofit’ is based on the principles of previous hot windbox repowering proposals, with additional modifications to permit operation without extensive coal boiler modifications. To achieve this, the heat recovery steam generator (HRSG) attached to GT is designed to maintain the main steam turbine flow rates and temperatures, to compensate for a necessary reduction in coal feed rates, and this, with the GT output, maintains the net power output of the site A techno-economic analysis of coal plants retrofitted with GT power cycles shows that these ‘power matched’ retrofits can be competitive with integrated retrofits at lower natural gas prices (as is now the case in North America). In particular, the novel GT flue gas windbox retrofit provides a promising alternative for adapting integrated capture retrofits that are initially designed for flexible operation with zero to full (~90%) capture (as at the Boundary Dam 3 unit) for subsequent operation only with full capture. In this case the addition of a GT flue gas windbox retrofit will restore the full power output of the site with full CO2 capture and using the original capture plant. In general, techno-economic analysis shows that the economic performance of GT retrofit options depends on the site power export capacity. If there is no limit on power export then retrofits may advantageously also include an additional steam cycle, to give a combined cycle with the GT, otherwise retrofits with a single pressure HRSG producing process steam only are preferred.

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The present experiment compared two methods of training a simple arm position using auditory feedback: capture and search. The participants were four right-handed female college students. During capture, auditory feedback was delivered by the experimenter after the participant moved along a single axis into the target position. During search, auditory feedback was produced by the computer after the participant left clicked a mouse inside the target location. The results of a multi-element design showed that participants performed more accurately during capture training than search training. Pre-training and post-training probes, during which no auditory feedback was provided, showed similar fluctuations in accuracy across probe types. A retention check, performed seven days after the final training session, showed higher accuracy scores for search than capture, across all four participants. These findings suggest that TAGteach should incorporate an approach similar to search training to improve training outcomes.

Massachusetts Institute of Technology. Dept. of Nuclear Engineering. Thesis. 1969. Ph.D. / Vita. / Bibliography: leaves 383-385. / A method of analysing Ge(Li) thermal neutron capture gamma spectra to obtain total gamma yields has been developed. Tie method determines both the yields from the well resolved gamma peaks in a spectrum as well as the gamma yields from the unresolved gamma lines which appear in the continuum portion of a spectrum. Accounting for the unresolved continuum enables a large fraction of total emitted energy to be observed, and values of 100% +/- 15% are obtained for the cases studied. The techniques used involve the determination of a peak response function suitable for the Ge(Li) pair spectrometer spectra being studied. The response function is used to strip off the effects of the peaks upon the background and unresolved data continuum. The continuum, which is due only to the unresolved lines, is broken into energy bins of 210 keV width and the gamma yield per bin is calculated. Results of the analysis and normalized yields are given for the rare earth samples of: Nd, Sm, Eu, Gd, and Er. The capture data were obtained by using the MITR 4th irradiation facility operated with a Ge(Li) pair spectrometer. / by Thomas L. Harper, Jr. / Ph.D.

<p> The following thesis comprises the study of six resonances in the Na^23(p,γ)Mg^24 reaction, using a 40 cu. cm. Ge(Li) detector. These resonances are at proton energies, Ep = 512 Kev, 987 Kev, 1020 Kev, 1174 Kev, 1318 Kev and 1416 Kev. The decay scheme and branching ratios have been found for each of these resonances. Also the gamma transition widths have been found for all of these resonances, except the 1416 Kev resonance, and these transition widths have been employed in calculating the reduced gamma transition strengths for the above decays.</p> / Thesis / Master of Science (MSc)

In everyday life, we are constantly surrounded by a huge amount of information.Since our attentional resources are limited, we need to select just the stimuli that we want to process. Despite our voluntary attempt to select a precise information, it often occurs that a salient stimulus or event automatically captures our attention, regardless its irrelevance. The fact that we are immediately and unintentionally attracted by sudden visual onsets provides a clear advantage for our survival. However, in spite of that, the possibility to counteract visual distraction is fundamental for an efficient interaction with the environment, particularly when a salient but irrelevant stimulation repeatedly affects our visual system. And then, how can we resist from being continuously distracted by irrelevant repetitive onsets? The current work is aimed to explore the mechanisms that we use to filter irrelevant information, with a focus on habituation, an ancestral form of learning that has recently been associated to the decrement of attentional capture observed in several studies. This experience-dependent learning process is defined as a behavioral response decrement that results from repeated stimulation and that does not involve sensory or motor fatigue. I will first provide the reader with a general introduction (Chapter 1) concerning the visual attention field, with a particular emphasis on attentional capture and the filtering of irrelevant information. I will then (Chapter 2) try to disentangle the two main accounts concerning the nature of the distractor filtering, the first claiming that filtering is accomplished to shield target processing from interference (top-down inhibitory control hypothesis), and the second stating that the passive exposure to a repeating visual onset is sufficient to trigger learning-dependent mechanisms to filter the unwanted stimulation (habituation hypothesis). After providing strong evidence in favor of the latter account, I will then examine (Chapter 3) to what extent the filtering of irrelevant information that we achieve through the mechanisms underlying habituation is affected by contextual cues, showing that this kind of filtering is context-dependent. Finally (Chapter 4), motivated by the existence of a strong functional and anatomical link between attention and the oculomotor system, I will explore whether habituation affects also the oculomotor capture triggered by an onset distractor, showing that the execution of reflexive saccades is subject to habituation, while the programming component is not. Taken together, the results of the present work give a strong contribution to the attentional capture field in showing that both attentional and oculomotor capture are subject to habituation, that this form of learning is context-specific and that it occurs also when we are passively exposed to a visual irrelevant stimulus.

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