Slicing of silicon into sheet material. Silicon sheet growth development for the large area silicon sheet task of the low cost silicon solar array project

Fabrication of a prototype large capacity multiple blade slurry saw is considered. Design of the bladehead which will tension up to 1000 blades, and cut a 45 cm long silicon ingot as large as 12 cm in diameter is given. The large blade tensioning force of 270,000 kg is applied through two bolts acting on a pair of scissor toggles, significantly reducing operator set-up time. Tests with an upside-down cutting technique resulted in 100% wafering yields and the highest wafer accuracy yet experienced with MS slicing. Variations in oil and abrasives resulted only in degraded slicing results. A technique of continuous abrasive slurry separation to remove silicon debris is described

An analytical approach to integral resonant control of second-order systems

Peer reviewedPostprin

2001 NFLRC summer Institute evaluation: Web-based workshops for advanced reading & writing development & maintenance

NW26Evaluation of the 2001 NFLRC Summer Institute, Web-Based Workshops for Advanced Reading & Writing Development & Maintenance

Statistical Properties of Interacting Bose Gases in Quasi-2D Harmonic Traps

The analytical probability distribution of the quasi-2D (and purely 2D) ideal and interacting Bose gas are investigated by using a canonical ensemble approach. Using the analytical probability distribution of the condensate, the statistical properties such as the mean occupation number and particle number fluctuations of the condensate are calculated. Researches show that there is a continuous crossover of the statistical properties from a quasi-2D to a purely 2D ideal or interacting gases. Different from the case of a 3D Bose gas, the interaction between atoms changes in a deep way the nature of the particle number fluctuations.Comment: RevTex, 10pages, 4 figures, E-mail: [email protected]

Beyond the trial: A systematic review of real-world uptake and engagement with digital self-help interventions for depression, low mood, or anxiety

Background: Digital self-help interventions (including online or computerized programs and apps) for common mental health issues have been shown to be appealing, engaging, and efficacious in randomized controlled trials. They show potential for improving access to therapy and improving population mental health. However, their use in the real world, that is, as implemented (disseminated) outside of research settings, may differ from that reported in trials, and implementation data are seldom reported. Objective: We aimed to review peer-reviewed articles reporting user uptake and/or ongoing use, retention, or completion data (hereafter ‘usage data’ or, for brevity, ‘engagement’) from implemented pure self-help (unguided) digital interventions for depression, anxiety, or the enhancement of mood. Methods: We conducted a systematic search of the Scopus, Embase, MEDLINE, and PsychINFO databases for studies reporting user uptake and/or usage data from implemented digital self-help interventions for the treatment or prevention of depression or anxiety, or the enhancement of mood, from 2002 to 2017. Additionally, we screened the reference lists of included articles, citations of these articles, and the titles of articles published in Internet Interventions, Journal of Medical Internet Research (JMIR), and JMIR Mental Health since their inception. We extracted data indicating the number of registrations or downloads and usage of interventions. Results: After the removal of duplicates, 970 papers were identified, of which ten met the inclusion criteria. Hand-searching identified one additional article. The included articles reported on seven publically available interventions. There was little consistency in the measures reported. The number of registrants or downloads ranged widely, from eight to over 40,000 per month. From 21% to 88% of users engaged in at least minimal use (e.g. used the intervention at least once or completed one module or assessment), while 7–42% engaged in moderate use (completing between 40% and 60% of modular fixed-length programs or continuing to use apps after four weeks). Indications of completion or sustained use (completion of all modules or the last assessment or continuing to use apps after six weeks or more) varied from 0.5% to 28.6%. Conclusions: Available data suggest that uptake and engagement vary widely among the handful of implemented digital self-help apps and programs which have reported this, and that usage may vary from that reported in trials. Implementation data should be routinely gathered and reported to facilitate improved uptake and engagement, arguably among the major challenges in digital health

The Resummed Photon Spectrum in Radiative Upsilon Decays

We present a theoretical prediction for the photon spectrum in radiative Upsilon decay including the effects of resumming the endpoint region, E_\gamma -> M_\Upsilon/2. Our approach is based on NRQCD and the soft collinear effective theory. We find that our results give much better agreement with data than the leading order NRQCD prediction.Comment: 4 pages, 6 figure

Unimolecular reaction rates in solution and in the isolated molecule: Comparison of diphenyl butadiene nonradiative decay in solutions and supersonic jets

The recent study of diphenyl butadiene (DPB) in supersonic jets and in solution by Shepanski et al.(1) and by Courtney and Felming(2), respectively, provides an opportunity to compare the isomerization rates measured in the isolated molecule (jet) with those measured at very low viscosity in solution. These comparisons should shed light on the vibrational energy flows between “optical” and “reactive” modes in the isolated molecule and on the connection between activated, friction dependent, models of barrier crossing in solution,(3-5) and statistical RRK (or RRKM) theories of gas phase unimolecular reactions(6)