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For postsecondary students with disabilities influencing reading performance, printed class materials pose a substantial barrier and have a negative impact on academic achievement. Digital technologies offer alternative ways of accessing print materials for students with print‐related disabilities. Alternative media is a broad term that encompasses a variety of formats into which printed text is converted. Alternative media, together with assistive computer technologies designed to read aloud the text, provide a means to access textual information and bypass the difficult reading process. The purpose of this article is to provide an overview of model programs and pertinent research on the use of alternative media by postsecondary students with print disabilities; we will identify promising practices for students whose disabilities negatively influence reading performance. 相似文献
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C L Williston 《Bulletin of the Medical Library Association》1967,55(1):48-51
A library can represent the most valuable personal service which a medical society can offer to a physician; yet, libraries unfortunately are taking a lessening role in medical societies. Surveys show that medical society libraries have declined in number from seventy-one in 1942 to forty-eight at the present time. This paper offers a positive plan of action with the objective of enabling libraries to regain a position of eminence in medical societies. It is pointed out that there are four vital elements in stimulating the growth and development of a library. These are the constant enhancement of resources; the promotion of library services; the rendering of prompt, valuable services; and ultimately, the recognition of the library through gifts, endowments, and expressions of appreciation. 相似文献
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Describing the plastic deformation of aluminium softball bats 总被引:1,自引:1,他引:0
Hollow aluminium bats were introduced over 30 years ago to provide improved durability over wooden bats. Since their introduction,
however, interest in hollow bats has focused almost exclusively around their hitting performance. The aim of this study was
to take advantage of the progress that has been made in predicting bat performance using finite elements and apply it to describe
bat durability. Accordingly, the plastic deformation from a ball impact of a single-wall aluminum bat was numerically modelled.
The bat deformation from the finite-element analysis was then compared with experiment using a high-speed bat test machine.
The ball was modelled as an isotropic, homogeneous, viscoelastic sphere. The viscoelastic parameters of the ball model were
found from instrumented, high-speed, rigid-wall ball impacts. The rigid-wall ball impacts were modelled numerically and showed
good agreement with the experimentally obtained response. The strain response of the combined bat-ball model was verified
with a strain-gauged bat at intermediate ball impact speeds in the elastic range. The strain response of the bat-ball model
exhibited positive correlation with the experimental measurements. High-speed bat-ball impacts were performed experimentally
and simulated numerically at increasing impact speeds which induced correspondingly increased dent sizes in the bat. The plastic
deformation from the numerical model found good agreement with experiment provided the aluminium work hardening and strain
rate effects were appropriately described. The inclusion of strain rate effects was shown to have a significant effect on
the bat deformations produced in the finite-element simulations. They also helped explain the existence of high bat stresses
found in many performance models. 相似文献
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