1,139 research outputs found
Wind tunnel tests on an aircraft model fitted with a lifting fan unit installed in the body
Imperial Users onl
Pultrusion process characterization
Pultrusion is a process through which high-modulus, lightweight composite structural members such as beams, truss components, stiffeners, etc., are manufactured. The pultrusion process, though a well-developed processing art, lacks a fundamental scientific understanding. The objective here was to determine, both experimentally and analytically, the process parameters most important in characterizing and optimizing the pultrusion of uniaxial fibers. The effects of process parameter interactions were experimentally examined as a function of the pultruded product properties. A numerical description based on these experimental results was developed. An analytical model of the pultrusion process was also developed. The objective of the modeling effort was the formulation of a two-dimensional heat transfer model and development of solutions for the governing differential equations using the finite element method
Neuronal Control of Swimming Behavior: Comparison of Vertebrate and Invertebrate Model Systems
Swimming movements in the leech and lamprey are highly analogous, and lack homology. Thus, similarities in mechanisms must arise from convergent evolution rather than from common ancestry. Despite over 40 years of parallel investigations into this annelid and primitive vertebrate, a close comparison of the approaches and results of this research is lacking. The present review evaluates the neural mechanisms underlying swimming in these two animals and describes the many similarities that provide intriguing examples of convergent evolution. Specifically, we discuss swim initiation, maintenance and termination, isolated nervous system preparations, neural-circuitry, central oscillators, intersegmental coupling, phase lags, cycle periods and sensory feedback. Comparative studies between species highlight mechanisms that optimize behavior and allow us a broader understanding of nervous system function
Assessment of Emotional Competencies in Educational Leaders: Applying Daniel Goleman’s Work in Emotional Intelligences as a Means of Evaluating Dispositions Related to the Work of the School Leader
The study of best practices related to educational leadership is an emerging area for universities with programs training leaders in school improvement. Practices taught in educational leadership programs have long been related to the technical issues of school operations with emphasis in the areas of finance, law, organizational theory, and strategic planning. More recently, educational leadership programs have begun to focus on the skills required of a leader of instruction (Hallinger, 2003; Jason, 2001). Among areas of concentration for the instructional leader are assessment, collaboration, professional development, and curriculum design. Although the focus of educational leadership programs has changed, the resulting levels of student achievement in the public schools in reading and mathematics have been reported as lukewarm with younger students improving since 1971, but seventeen-year-olds showing no improvement (Perie & Moran, 2004). Moreover, these student achievement results have been perceived by the public as less than desirable. According to survey results released by the Educational Testing Service in June of 2004, only 22% of adults surveyed gave American schools a grade of B or above (Parents Take Schools, 2004)
Field Performance and Quality of Hybrid Winter Wheat.
End of Project ReportAn assessment of hybrid winter wheat was carried out over three seasons to
determine the commercial potential of hybrid varieties under Irish conditions. The
studies examined the effects of reduced seeding rate on hybrid grain yield and
quality in comparison to pure-line varieties. A comparison of the hybrid varieties
available was also carried out and the higher yielding hybrids were then compared
with the best pure-line varieties in terms of grain yield and quality, and response
to fungicide.
The results indicated that in good sowing conditions hybrids can give greater
yields than pure-line varieties at reduced seeding rates, but the effect is not large
or consistent. There was generally no effect of seeding rate on the grain quality of
hybrid varieties but crop lodging occurred in one season at high seeding rates.
Of the hybrid varieties examined, Mercury and Hyno Esta were the two better
varieties in terms of grain yield; there was little difference between the hybrids
examined in terms of grain quality.
The best hybrid varieties did not give consistently higher yields or quality than the
best pure-line varieties and exhibited a similar response to fungicide application as
the pure-line varieties. It is concluded that when the price differential between
seed of pure-line varieties and hybrid varieties is taken into account, the winter
wheat hybrid varieties currently available do not offer any economic advantages
to commercial growers at the present time
Synchronous stimulation in the rubber hand illusion task boosts the subsequent sense of ownership on the vicarious agency task
The relationship between sense of agency and sense of ownership remains unclear. Here we investigated this relationship by manipulating ownership using the rubber hand illusion and assessing the resulting impact on self-experiences during the vicarious agency illusion. We tested whether modulating ownership towards another limb using the rubber hand illusion would subsequently influence the illusory experience of ownership and agency towards a similar-looking limb in the vicarious agency task. Crucially, the vicarious agency measures both sense of agency and sense of ownership at the same time, while removing the confounding influence of motor signals. Our results replicated the well-established effects of both paradigms. We also found that manipulating the sense of ownership with the rubber hand illusion influenced the subsequent vicarious experience of ownership but not the vicarious experience of agency. This supports the idea that sense of agency and sense of ownership are, at least partially, independent experiences
Contributors to the January Issue/Notes
Notes by John J. Killen, James H. Neu, John W. Hackett, Jr., James E. Diver, James C. Daner, Richard F. Swisher, and Leo L. Linck
Contributors to the January Issue/Notes
Notes by John J. Killen, James H. Neu, John W. Hackett, Jr., James E. Diver, James C. Daner, Richard F. Swisher, and Leo L. Linck
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