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The Cosmology Large Angular Scale Surveyor (CLASS) is an experiment to measure the signature of a gravita-tional-wave background from inflation in the polarization of the cosmic microwave background (CMB). CLASS is a multi-frequency array of four telescopes operating from a high-altitude site in the Atacama Desert in Chile. CLASS will survey 70\% of the sky in four frequency bands centered at 38, 93, 148, and 217 GHz, which are chosen to straddle the Galactic-foreground minimum while avoiding strong atmospheric emission lines. This broad frequency coverage ensures that CLASS can distinguish Galactic emission from the CMB. The sky fraction of the CLASS survey will allow the full shape of the primordial B-mode power spectrum to be characterized, including the signal from reionization at low $\ell$. Its unique combination of large sky coverage, control of systematic errors, and high sensitivity will allow CLASS to measure or place upper limits on the tensor-to-scalar ratio at a level of $r=0.01$ and make a cosmic-variance-limited measurement of the optical depth to the surface of last scattering, $\tau$., Comment: 23 pages, 10 figures, Presented at SPIE Astronomical Telescopes and Instrumentation 2014: Millimeter, Submillimeter, and Far-Infrared Detectors and Instrumentation for Astronomy VII. To be published in Proceedings of SPIE Volume 9153

We describe the instrument architecture of the Johns Hopkins University-led CLASS instrument, a groundbased cosmic microwave background (CMB) polarimeter that will measure the large-scale polarization of the CMB in several frequency bands to search for evidence of inflation.

The Cosmology Large Angular Scale Surveyor (CLASS) experiment aims to map the polarization of the Cosmic Microwave Background (CMB) at angular scales larger than a few degrees. Operating from Cerro Toco in the Atacama Desert of Chile, it will observe over 65% of the sky at 38, 93, 148, and 217 GHz. In this paper we discuss the design, construction, and characterization of the CLASS 38 GHz detector focal plane, the first ever Q-band bolometric polarimeter array., Comment: 15 pages, 4 figures. Presented at SPIE Astronomical Telescopes and Instrumentation 2014: Millimeter, Submillimeter, and Far-Infrared Detectors and Instrumentation for Astronomy VII. To be published in Proceedings of SPIE Volume 9153

Variable-delay Polarization Modulators (VPMs) are currently being implemented in experiments designed to measure the polarization of the cosmic microwave background on large angular scales because of their capability for providing rapid, front-end polarization modulation and control over systematic errors. Despite the advantages provided by the VPM, it is important to identify and mitigate any time-varying effects that leak into the synchronously modulated component of the signal. In this paper, the effect of emission from a $300$ K VPM on the system performance is considered and addressed. Though instrument design can greatly reduce the influence of modulated VPM emission, some residual modulated signal is expected. VPM emission is treated in the presence of rotational misalignments and temperature variation. Simulations of time-ordered data are used to evaluate the effect of these residual errors on the power spectrum. The analysis and modeling in this paper guides experimentalists on the critical aspects of observations using VPMs as front-end modulators. By implementing the characterizations and controls as described, front-end VPM modulation can be very powerful for mitigating $1/f$ noise in large angular scale polarimetric surveys. None of the systematic errors studied fundamentally limit the detection and characterization of B-modes on large scales for a tensor-to-scalar ratio of $r=0.01$. Indeed, $r, 13 pages, 13 figures, 1 table, matches published version

Objective: Home telemonitoring improves clinical outcomes but can generate large amounts of data. Automating data surveillance with clinical decision support could reduce the impact of translating these systems to clinical settings. We utilized time-motion methodology to measure the time spent on activities monitoring subjects in the two groups of a home spirometry telemonitoring randomized controlled trial: the manual nurse review (control) group and the automated review (intervention) group. These results are examined for potential workflow effects that could occur when the intervention translates to a clinical setting. Materials and Methods: Time motion is an established industrial engineering technique used to evaluate workflow by measuring the time of predefined, discrete tasks. Data were collected via direct observation of two research nurses by a single observer using the repetitive or snap-back timing method. All observed tasks were coded using a list of work activities defined and validated in an earlier study. Reliability data were collected during a 2-h session with a secondary observer. Results: Reliability of the primary observer was established. During 35 h of data collection, a sample of 938 task observations were recorded and coded using 46 previously defined and 5 newly defined work activities. Between-group comparisons of activity time for subjects in the two study groups showed significantly more time spent on data review activities for the automated review group. Reclassification of the 51 observed activities identified 15 activities that would translate to a clinical setting, of which 5 represent potentially new activities. Conclusions: Implementing an intervention into a clinical setting could add work activities to the clinical workflow. Time-motion study of research personnel working with new clinical interventions provides a template for evaluating the workflow impact of these interventions prior to translation from a research to a clinical setting.