Development of basic theories and techniques for determining stresses in rotating turbine or compressor blades

A method for measuring in-plane displacement of a rotating structure by using two laser speckle photographs is described. From the displacement measurements one can calculate strains and stresses due to a centrifugal load. This technique involves making separate speckle photographs of a test model. One photograph is made with the model loaded (model is rotating); the second photograph is made with no load on the model (model is stationary). A sandwich is constructed from the two speckle photographs and data are recovered in a manner similar to that used with conventional speckle photography. The basic theory, experimental procedures of this method, and data analysis of a simple rotating specimen are described. In addition the measurement of in-plane surface displacement components of a deformed solid, and the application of the coupled laser speckle interferometry and boundary-integral solution technique to two dimensional elasticity problems are addressed

Manual for extending the laser specklegram technique to strain analysis of rotating components

The theory, techniques, and equipment necessary for extending laser speckle techniques to analyze stresses in rotating blades are described. Details for setting up the equipment, for timing the events, for data recording, and for data analysis are discussed. Finite element techniques are investigated for analysis of speckle data. Advantages and limitations of the finite element analysis for the speckle data are discussed. The finite element program is listed

Numerical solution of the Navier-Stokes equations for arbitrary two-dimensional multi-element airfoils

The development of a numerical simulation of time dependent, turbulent, compressible flow about two dimensional multi-element airfoils of arbitrary shape is described. The basis of this simulation is a technique of automatic numerical generation of coordinate systems fitted to the multiple bodies regardless of their number or shape. Procedures developed whereby the coordinate lines are automatically concentrated in the boundary layer at any Reynolds number are discussed. The compressible turbulent solution involves an algebraic eddy viscosity turbulence model. The laminar version was run for transonic flow at free stream Mach numbers up to 0.9

Energy Fact Sheet: Residential Solar Heating

Heating a residence and the domestic water supply with solar energy is technically feasible in Kentucky. However, it is not feasible to provide 100 percent of the heat requirements. Some backup system is needed for continuous heat during cloudy weather and the cold part of winter. Both passive and active solar heating systems are technically feasible

A systematic review of associations between environmental exposures and development of asthma in children aged up to 9 years

Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.Peer reviewedPublisher PD

A Hessenberg Markov chain for fast fibre delay line length optimization

In this paper we present an approach to compute the invariant vector of the N + 1 state Markov chain P presented in (Rogiest et al., Lecture Notes in Computer Science, NET-COOP 2007 Special Issue, pp. 4465:185-194) to determine the loss rate of an FDL buffer consisting of N lines, by solving a related Hessenberg system (i.e., a Markov chain skip-free in one direction). This system is obtained by inserting additional time instants in the sample paths of P and allows us to compute the loss rate for various FDL lengths by solving a single system. This is shown to be especially effective in reducing the computation time of the heuristic LRA algorithm presented in (Lambert et al., Proc. NAEC 2005, pp. 545-555) to optimize the FDL lengths, where improvements of several orders of magnitude can be realized

The Dark Matter Telescope

Weak gravitational lensing enables direct reconstruction of dark matter maps over cosmologically significant volumes. This research is currently telescope-limited. The Dark Matter Telescope (DMT) is a proposed 8.4 m telescope with a 3 degree field of view, with an etendue of 260 $(m. degree)^2$, ten times greater than any other current or planned telescope. With its large etendue and dedicated observational mode, the DMT fills a nearly unexplored region of parameter space and enables projects that would take decades on current facilities. The DMT will be able to reach 10-sigma limiting magnitudes of 27-28 magnitude in the wavelength range .3 - 1 um over a 7 square degree field in 3 nights of dark time. Here we review its unique weak lensing cosmology capabilities and the design that enables those capabilities.Comment: in-press version with additions; to appear in proceedings of the Dark Matter 2000 conference (Santa Monica, February 2000) to be published by Springe

Spontaneous Subarachnoid Haemorrhage: Some Aspects of its Pathogenesis and Management

The recognition of spontaneous subarachnoid haemorrhage as a clinical entity, distinct from the many other conditions all previously grouped under the comprehensive heading of Apoplexy was first made by Collier in 1922. A year or so later Symonds reviewed 124 cases described m the literature and concluded that rupture of an intracranial aneurysm was probably the major cause of this syndrome. His opinion is now widely held, and it seems probable that on a proportionate basis the main aetiological factors are:-1. Rupture of an intracranial aneurysm responsible for 80% of cases.2. Arteriovenous malformations responsible for 10% of cases.3. Other diseases (e.g. neoplasm. blood dyscrasia)- responsible for I 0% of cases.The content of this article is largely referable to spontaneous subarachnoid haemorrhage following rupture of an intracranial aneurysm

High Resolution Scanning Auger Microscopy of Mineral Surfaces

There are a number of cases where scanning Auger microscopy can be used to determine the near-surface composition of minerals with extremely high lateral resolution. This involves collecting Auger spectra with reasonable signal to noise ratios without encountering significant beam induced charging or surface degradation, even if the beam is impinging on a grain less than 1μm in diameter. We typically use a 3 keV beam with less than 10 nA beam current on a sample surface that is tilted (to increase backscattered and secondary electron emission efficiency) and relatively flat. To further minimize surface degradation, vacuum levels are kept high and the beam is rastered or defocused whenever possible. The Auger spectra of minerals can be used to study modification of surfaces due to geochemical influences or to identify submicron grains if the near-surface composition is representative of the bulk composition. Also, high lateral resolution step scans can be performed across sharp interfaces between two grains, allowing for short-range studies of solid-solid interactions in rocks at grain boundaries. We also report on preliminary attempts to chemically quantify Auger peak intensities for silicate minerals. Measurements of peak-to-peak heights for oxygen and silicon lines for eight silicate minerals of well-known composition indicate that Auger sensitivity factors can vary significantly with O/Si ratio

lmmunocontraception in White-Tailed Deer

lmmunocontraception may have management application for white-tailed deer populations in parks and preserves. where hunting 1s illegal or impractical. This study examines physiological aspects of immunocontraception with porcine zonae pellucidae in 53 fertile white-tailed does. In separate studies, we employed protocols of three and two porcine zonae pellucidae (PZP) injections as well as two different protocols using one injection. Each one-injection vaccination consisted of one dose of porcine zonae pellucidae as in other protocols plus a second controlled-release dose of the material delivered via an osmotic minipump implant or injected, biodegradable polymer microspheres. We monitored fawn production for 1 to 3 years in all does and measured serum PZP antibody titers at various times after treatment in 15 randomly selected PZP does and in 2 control does. All three-injection PZP does were give a single PZP booster inoculation after 1 year. None of the two- or three-injection does and none of the one-injection does with a minipump produced fawns the first year after treatment, whereas two of seven does given a single injection with controlled-release microspheres produced fawns. In 49 control-doe breeding seasons, the pooled incidence of fawn production was 93.8 percent. Regarding reversibility of infertility, the incidence of fawn production was 75 % within 2 years after treatment was discontinued. Serum anti-PZP antibody titers were present only after PZP treatment, and highest titers occurred in does given two or three separate PZP injections. PZP-treated does showing \u3e50% of maximal antibody titers at the onset of a breeding season did not produce fawns; those showing \u3c33% of maximal titers did. These data demonstrate in white-tailed does that (1)multiple-injection PZP vaccination can produce complete contraception for at least one breeding season, (2) the contraceptive effect is reversible within 2 years in most does, (3) an elevated anti-PZP antibody titer occurs after PZP vaccination, and (4) multiple-injection PZP vaccination produces a sustained antibody response through at least one breeding season. In separate field studies of wild, free-roaming deer in three locations, we successfully lured does to within darting range using bait stations. In two locations, we attempted and achieved remote delivery PZP vaccination of 60-9- percent of does. In the one location for which we have data on fawn production, the fawning incidence was 0/10, 6/9, and 8/9 for two- and one-injection porcine zonae pellucidae and untreated controls, respectively. In the same location, we monitored seasonal aspects of activity, behavior, and physical condition. We also determined that there is a good potential for remote assessment of pregnancy in does using measurement of pregnancy-specific elevations of steroid metabolites in fecal samples