Limit analysis of flow through conical converging dies

A variety of mathematical models may be used to analyse plastic deformation during a metal-forming process. One of these methods—limit analysis—places the estimate of required power between an upper bound and a lower bound. The upper and lower bound analyses are designed so that the actual power or forming stress requirement is less than that predicted by the upper bound and greater than that predicted by the lower bound. Finding a lower upper bound and a higher lower bound reduces the uncertainty of the actual power requirement. Upper and lower bounds will permit the determination of such quantities as required forces, limitations on the process, optimal die design, flow patterns, and prediction and prevention of defects.Fundamental to the development of both upper bound and lower bound solutions is the division of the body into zones. For each of the zones there is written either a velocity field (upper bound) or a stress field (lower bound). A better choice of zones and fields brings the calculated values closer to actual values.In the present work, both upper and lower bound solutions are presented for axisymmetric flow through conical converging dies. For the upper bound triangular velocity fields have been solved and compared to previously published work on spherical velocity fields. It is found that each type provides a lower solution over a part of the range of process variables. A previously published lower bound solution for axisymmetric flow is refined.     

Competition,gender and the sport experience: an exploration among college athletes

Worldwide, sport and physical activity rates of women generally lag behind those of men. One reason for this could be the way that sport cultures typically frame and value competition. This study provides an examination of the meaning and impact of ‘competition’ on the sport participation experiences of men and women. Using Interpretative Phenomenological Analysis, individual and group interviews were conducted with 76 current and former male and female collegiate athletes from both varsity and club sports regarding the impact of competition on their sport experiences. Results revealed that women and men tended to view and interpret competition differently, which strongly impacted their sport experiences. Sport programming that embraces a balance of cooperation and competition may be valuable for attracting and retaining both male and female participants.     

Coupled physical and digital cadaver dissection followed by a visual test protocol provides insights into the nature of anatomical knowledge and its evaluation

This research effort compared and contrasted two conceptually different methods for the exploration of human anatomy in the first‐year dissection laboratory by accomplished students: “physical” dissection using an embalmed cadaver and “digital” dissection using three‐dimensional volume modeling of whole‐body CT and MRI image sets acquired using the same cadaver. The goal was to understand the relative contributions each method makes toward student acquisition of intuitive sense of practical anatomical knowledge gained during “hands‐on” structural exploration tasks. The main instruments for measuring anatomical knowledge under this conceptual model were questions generated using a classification system designed to assess both visual presentation manner and the corresponding response information required. Students were randomly divided into groups based on exploration method (physical or digital dissection) and then anatomical region. The physical dissectors proceeded with their direct methods, whereas the digital dissectors generated and manipulated indirect 3D digital models. After 6 weeks, corresponding student anatomical assignment teams compared their results using photography and animated digital visualizations. Finally, to see whether each method provided unique advantages, a visual test protocol of new visualizations based on the classification schema was administered. Results indicated that all students, regardless of gender, dissection method, and anatomical region dissected performed significantly better on questions presented as rotating models requiring spatial ordering or viewpoint determination responses in contrast to requests for specific lexical feature identifications. Additional results provided evidence of trends showing significant differences in gender and dissection method scores. These trends will be explored with further trials with larger populations. Anat Sci Ed 1:27–40, 2008. © 2007 American Association of Anatomists.     

Visual and language processing deficits in compensated and uncompensated college students with dyslexia

In seven experiments, we investigated whether compensated and uncompensated adults with dyslexia show different patterns of deficits in magnocellular visual processing and in language processing tasks. In four visual tasks, we failed to find evidence of magnocellular deficits in either group. However, both groups of adults with dyslexia showed deficits in component language skills, and the degree of reading impairment predicted the nature and extent of these deficits. Uncompensated readers showed deficits in orthographic and especially phonological coding and awareness and were slower on rapid naming. Compensated readers showed word and nonword performance below controls but better than the uncompensated readers. The compensated group was not significantly less accurate than controls on phonological awareness, nor significantly worse overall on rapid naming.