Abradable compressor and turbine seals, volume 2

The applications and advantages of abradable coatings as gas path seals in a general aviation turbofan engine were investigated. Abradable materials were evaluated for the high pressure radial compressor and the axial high and low pressure turbine shrouds

Abradable compressor and turbine seals, volume 1

The application and advantages of abradable coatings as gas-path seals in a general aviation turbine engine were evaluated for use on the high-pressure compressor, the high-pressure turbine, and the low-pressure turbine shrouds. Topics covered include: (1) the initial selection of candidate materials for interim full-scale engine testing; (2) interim engine testing of the initially selected materials and additional candidate materials; (3) the design of the component required to adapt the hardware to permit full-scale engine testing of the most promising materials; (4) finalization of the fabrication methods used in the manufacture of engine test hardware; and (5) the manufacture of the hardware necessary to support the final full-scale engine tests

Feeding the Dry Cow to Avoid Parturient Paresis

In the past, dairy producers have regarded the non-lactating or dry period as a time when the dairy cow recuperates from the stresses of her previous lactation and prepares herself for parturition. This kind of thinking usually results in mismanagement of the dry cow since she is seen as an economic drain on the farm. Today this image is changing and through years of research and education the dry period is now considered a vital stage of preparation for the next lactation period. The dry cow should be managed and fed to prepare her for the transition from the low metabolic demand needed during the dry period to the higher metabolic demand of early lactation. If cows are not prepared properly for this transition, periparturient diseases, primarily in the form of metabolic problems, are inevitably going to occur. These problems include: milk fever, retained placenta, dystocia, uterine prolapse, ketosis, fatty liver syndrome, and displaced abomasum

At-Risk Preschoolers Become Beginning Readers With Neurologically Integrated Alphabet Instruction

This is the author's accepted manuscript. The publisher's version is available on their website.Massengill Shaw, D., & Sundberg, M.L. (2008). At-risk preschoolers become beginning readers with neurologically integrated alphabet instruction. Journal of Education Research, 2(1), 61-73

How A Neurologically Integrated Approach Which Teaches Sound-Symbol Correspondence and Legible Letter Formations Impacts At-Risk First Graders

This is the author's accepted manuscript. The publisher's official version is available at: http://www.eric.ed.gov/PDFS/EJ942830.pdfThe setting of this study took place in an inner city. The purpose was to determine the effectiveness of a neurologically integrated approach in teaching 43 at-risk pre-first graders their letter sounds and formations during 45-50 hours of summer school. There were four sequential phases to teaching this alphabetic approach: imagery, auditory, integration and sound blending, and motor plan. Students received three pre and post-tests: sound, letter formation, and phonic knowledge as assessed through alphabet exercises and the Early Reading Screening Instrument. Repeated measures and descriptive statistics of the three assessments were used to measure growth. Results indicate that despite an average attendance of 84%, significant changes occurred in the students’ knowledge of letter sounds, letter formations and their ability to write words (phonics). It is recommended to explicitly teach at-risk children their alphabet knowledge through a neurologically integrated approach that mirrors brain development

Organic Agriculture in the landscape of sustainability initiatives

Organic is not the only initiative with the aim of improving sustainability in agriculture. There is a wide array of approaches, perspectives, priorities and levels of ambition. Certain initiatives are seen as complimentary to Organic Agriculture and use it as a basis. Others are viewed as followers, competitors or – due to lower sustainability requirements – even as "greenwashers". As not all assessments of standards and impacts recognize a leading position for Organic farming, there is room for improvement

A Unique, Neurologically Integrated Approach Designed to Teach Letter Sounds and Formations

The purpose of this article is to present an integrated alphabetic approach that simultaneously teaches letter sounds and formations. We share with you the research that supports this integrated approach and present the procedures to implement this approach. Further, we document the effect of using this new integrated alphabet approach on the accuracy with which students learned to produce letter sounds and formations in two situations: first grade classrooms in a school in a Midwest suburb and in an inner city post-kindergarten summer school. Also, teacher comments and student voices are included. Results show that students who received integrated alphabet instruction reduced their sound and letter formation errors. Also, teachers advocate for one approach that simultaneously teaches phonics and handwriting. The findings of this study support the value of employing a methodology that combines instruction in letter sounds and letter formations through a neurologically integrated system

Caustic formation in a non-Gaussian model for turbulent aerosols

Caustics in the dynamics of heavy particles in turbulence accelerate particle collisions. The rate $\mathscr{J}$ at which these singularities form depends sensitively on the Stokes number St, the non-dimensional inertia parameter. Exact results for this sensitive dependence have been obtained using Gaussian statistical models for turbulent aerosols. However, direct numerical simulations of heavy particles in turbulence yield much larger caustic-formation rates than predicted by the Gaussian theory. In order to understand possible mechanisms explaining this difference, we analyse a non-Gaussian statistical model for caustic formation in the limit of small St. We show that at small St, $\mathscr{J}$ depends sensitively on the tails of the distribution of Lagrangian fluid-velocity gradients. This explains why different authors obtained different St-dependencies of $\mathscr{J}$ in numerical-simulation studies. The most-likely gradient fluctuation that induces caustics at small St, by contrast, is the same in the non-Gaussian and Gaussian models. Direct-numerical simulation results for particles in turbulence show that the optimal fluctuation is similar, but not identical, to that obtained by the model calculations.Comment: 12 pages, 3 figures, 1 tabl