Interim prediction method for externally blown flap noise

An interim procedure for predicting externally blown flap (EBF) noise spectra anywhere below a powered lift aircraft is presented. Both engine-under-the-wing and engine-over-the-wing EBF systems are included. The method uses data correlations for the overall sound pressure level based on nozzle exit area and exhaust velocity along with OASPL directivity curves and normalized one-third-octave spectra. Aircraft motion effects are included by taking into account the relative motion of the source with respect to the observer and the relative velocity effects on source strength

True Airspeed Measurement by Ionization-Tracer Technique

Ion bundles produced in a pulse-excited corona discharge are used as tracers with a radar-like pulse transit-time measuring instrument in order to provide a measurement of airspeed that is independent of all variables except time and distance. The resulting instrumentation need not project into the air stream and, therefore, will not cause any interference in supersonic flow. The instrument was tested at Mach numbers ranging from 0.3 to 3.8. Use of the proper instrumentation and technique results in accuracy of the order of 1 percent

Effect of configuration variation on externally blown flap noise

The sensitivity of flap interaction noise to variations in engine-under-the-wing externally blown flap geometry was investigated with a large cold-flow model. Both 2- and 3-flap wing sections (7-ft chord) with trailing flap angles up to 60 deg were employed. Exhaust nozzles included coaxial, plug, and 8- and 13-inch diameter conical configurations. These nozzles were tested at two positions below the wing. The effects of these geometry variations on noise level, directivity, and spectral shape are summarized in terms of exhaust flow parameters evaluated at the nozzle exit and at the flap impingement station. The results are also compared with limited flap noise data available from tests using real engines

Interim prediction method for low frequency core engine noise

A literature survey on low-frequency core engine noise is presented. Possible sources of low frequency internally generated noise in core engines are discussed with emphasis on combustion and component scrubbing noise. An interim method is recommended for predicting low frequency core engine noise that is dominant when jet velocities are low. Suggestions are made for future research on low frequency core engine noise that will aid in improving the prediction method and help define possible additional internal noise sources

Pharmacotherapy for weight loss: the cardiovascular effects of the old and new agents

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/108287/1/jcpt12177.pd

Telecommunications systems design techniques handbook

Handbook presents design and analysis of tracking, telemetry, and command functions utilized in these systems with particular emphasis on deep-space telecommunications. Antenna requirements are also discussed. Handbook provides number of tables outlining various performance criteria. Block diagrams and performance charts are also presented

Modelling the AM CVn and Double Detonation Supernova Progenitor Binary System CD-30∘^{\circ}11223

We present a detailed modelling study of CD-30$^{\circ}$11223 (CD-30), a hot subdwarf (sdB)-white dwarf (WD) binary identified as a double detonation supernova progenitor, using the open-source stellar evolution software MESA. We focus on implementing binary evolution models carefully tuned to match the observed characteristics of the system including $\log g$ and $T_{\rm eff}$. For the first time, we account for the structure of the hydrogen envelope throughout the modelling, and find that the inclusion of element diffusion is important for matching the observed radius and temperature. We investigate the two sdB mass solutions (0.47 and 0.54 $M_{\odot}$) previously proposed for this system, strongly favouring the 0.47 $M_{\odot}$ solution. The WD cooling age is compared against the sdB age using our models, which suggest an sdB likely older than the WD, contrary to the standard assumption for compact sdB-WD binaries. Subsequently, we propose a possible alternate formation channel for CD-30. We also perform binary evolution modelling of the system to study various aspects such as mass transfer, orbital period evolution and luminosity evolution. Our models confirm CD-30 as a double detonation supernova progenitor, expected to explode $\approx55$ Myr from now. The WD accretes a $\approx0.17$ $M_{\odot}$ thick helium shell that causes a detonation, leaving a 0.30 $M_{\odot}$ sdB ejected at $\approx$750 km/s. The final 15 Myr of the system are characterised by helium accretion which dominates the system luminosity, possibly resembling an AM CVn-type system.Comment: 12 pages, 8 figures. Accepted for publication in MNRA

A Web Application for Self-Monitoring Improves Symptoms in Chronic Systolic Heart Failure

Objective: The objective of this study was to determine if a Web application that promoted mindfulness of the progress of the chronic disease through self-monitoring improved quality of life in heart failure. Materials and Methods: This was a prospective single-center single-group study. Participants were instructed how to use the Web application and to perform self-monitoring daily for 12 weeks. A comprehensive physical exam, assessment of New York Heart Association (NYHA) class, the Minnesota Living with Heart Failure Questionnaire (MLHFQ), and an evaluation of self-management were performed in person at baseline and at 12 weeks. Results: Participants consisted of older (mean, 59 years), predominantly female (63%) adults with NYHA class II or III symptoms. NYHA classification (preintervention versus postintervention, 2.5±0.13 versus 2.0±0.13; p=0.0032) and MLHFQ score (55.7±4.6 versus 42.6±5.1, respectively; p=0.0078) improved over 12 weeks of self-monitoring. A trend toward improvement was also demonstrated in weight (preintervention versus postintervention, 209±9.6 pounds versus 207±9.4 pounds; by paired t test, p=0.389), number of times exercised per week (1.29±0.5 versus 2.5±0.6, respectively; p=0.3), and walk distance (572±147 yards versus 845±187 yards, respectively; p=0.119). Jugular venous distention (preintervention versus postintervention, 8.1±0.6?cm versus 6.7±0.3?cm; p=0.083) and peripheral edema (29.2% versus 16.7%, respectively; p=0.375) decreased after 12 weeks of self-monitoring via the Web application. Conclusions: A Web application for self-monitoring heart failure over 12 weeks improved both NYHA classification and MLHFQ score. The trend in improved physical activity and physical exam support these outcomes. The number of patients reporting a sodium-restricted diet increased over the 12 weeks, which may have led to the positive findings.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/140281/1/tmj.2014.0095.pd

The Higgs vacuum uplifted: revisiting the electroweak phase transition with a second Higgs doublet

The existence of a second Higgs doublet in Nature could lead to a cosmological first order electroweak phase transition and explain the origin of the matter-antimatter asymmetry in the Universe. We explore the parameter space of such a two-Higgs-doublet-model and show that a first order electroweak phase transition strongly correlates with a significant uplifting of the Higgs vacuum w.r.t. its Standard Model value. We then obtain the spectrum and properties of the new scalars H0, A0 and H± that signal such a phase transition, showing that the decay A0 → H0Z at the LHC and a sizable deviation in the Higgs self-coupling λhhh from its SM value are sensitive indicators of a strongly first order electroweak phase transition in the 2HDM

The diet of red-throated divers (Gavia stellata) overwintering in the German Bight (North Sea) analysed using molecular diagnostics

In Europe, the German Bight is one of the most important non-breeding areas for protected red-throated divers (Gavia stellata). It is unclear what attracts the birds to this area, especially as the food composition of seabirds outside the breeding season is notoriously difficult to study. To obtain information on prey species composition of red-throated divers in this area, faecal samples from 34 birds caught alive were analysed using DNA metabarcoding. Prey DNA was detected in 85% of the samples with a mean number of 4.2 ± 0.7 taxa per sample (n = 29). Altogether, we found a broad prey spectrum with 19 fish taxa from 13 families dominated by five groups: clupeids, mackerel, gadoids, flatfish and sand lances with clupeids being the most frequently detected prey. Our results indicate that red-throated divers are generalist opportunistic feeders in the German Bight, but pelagic schooling fish that aggregate at frontal zones and have a high energetic value might be favoured. Atlantic mackerel appears to be a more important prey for red-throated divers in this area than previously thought. The precision achievable using metabarcoding has revealed a number of prey species that are consumed by red-throated divers in the German Bight, which helps to explain the selection of this area by divers in winter and spring