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131.
In this study, a simple roller burnishing tool was made to operate burnishing processes on A356/5%SIC metal matrix composite fabricated by electromagnetic stir casting under different parameters. The effects of burnishing speed, burnishing force and number of burnishing passes on the surface roughness and tribological properties were measured. Scanning electron microscopy (SEM) graphs of the machined surface with PCD (insert-10) tool and roller burnished surface with tungsten carbide (WC) roller were taken into consider- ation to observe the surface finish of metal matrix composites. The mechanical properties (tensile strength, hardness, duc- tility) of A356/5%SIC metal matrix composites were studied for both unburnished samples and burnished samples. The results revealed that the roller burnished samples of A356/ 5%SIC led to the improvement in tensile strength, hardness and ductility. In order to find out the effects of roller bur- nishing process parameters on the surface roughness of A356/ 5%SIC metal matrix composite, response surface methodol- ogy (RSM) (Box-Behnken design) was used and a prediction model was developed relevant to average surface roughness using experimental data. In the range of process parameters, the result shows that roller burnishing speed increases, and surface roughness decreases, but on the other hand roller burnishing force and number of passes increase, and surface roughness increases. Optimum values of burnishing speed (1.5 m/s), burnishing force (50 N) and number of passes (2) during roller burnishing of A356/5%SIC metal matrix com- posite to minimize the surface roughness (predicted 1.232 μm) have been found out. There was only 5.03% error in the experimental and modeled results of surface roughness. 相似文献
132.
Margaret K. Merga 《Library & information science research》2021,43(2):101091
Libraries provide readers' advisory services to young people to foster reading for pleasure. The Booktok community on TikTok is a resource that can be drawn upon to support promotion of books with this demographic. A hybrid content analysis of 116 TikTok videos explores presence of hashtags, authors and books, and recurring themes promoted in Booktok videos. Popular hashtags build community and promoted authors and books are a small and select group. Young people use Booktok to provide recommendations, explore reader experience and emotional response, generate reader community and identity, discuss fictional characters and places, develop and promote writing, and discuss personal library management and being a reader in the family. Libraries' reader advisory services for young people can use these findings to employ language of the discourse community for insider signposting of the library's physical space and give greater primacy to the emotional response evoked by books and reading. 相似文献
133.
Kumar Laxman 《Journal of Research in Special Educational Needs》2022,22(2):158-166
This pilot study set out to examine the impact of a regular practice of yoga within schooling curricular hours on the well-being and behaviors of atypically developing children. The design of this study was based on a qualitative hermeneutic-phenomenology approach. The intervention consisted of 5 weekly sessions of yoga of 15 minutes each and composed of breathing techniques (pranayama), postures (pranayama), and lying down relaxation exercises (yoga nidra). The research site was a special needs school in South Auckland, New Zealand in an area characterized by poor socio-economic living conditions with a composite range of different ethnic groups. The findings of this study suggest that a regular practice of yoga can have numerous benefits for children on the Autism Spectrum Disorder (ASD). They found yoga to be a fun-filled and engaging experience. They improved significantly in their flexibility levels and general physical health. Emotionally, the children reported that the breathing techniques allowed them to feel calmer and more relaxed. The children felt that incorporating a regular practice of yoga within formal curriculum will be another effective tool to enhancing their overall health and well-being. 相似文献
134.
Tracy R. Nichols Margaret Brown Sheryl L. Coley Allyson Kelley Kelly Mauceri 《The Journal of perinatal education》2014,23(2):79-88
The aim of this study was to understand adolescent mothers’ childbirth experiences. Semistructured interviews were conducted with participants recruited from a community-based program for adolescent mothers. Fourteen mothers described their birth experiences. Using a narrative analytic approach, responses were reconstructed into birth stories. Stories, condensed into poetic form, were compared and contrasted. Four unique categories emerged: connected births, surreal births, disconnected births, and disempowered births. Categories differed by agency, support, and emotional tone. Positive support was found in stories that portrayed high agency and positive affect, whereas problematic support was apparent in stories that conveyed passivity, frustration, and disappointment. This study has implications for tailoring childbirth education for adolescent mothers and can inform health-care professionals working with this population. 相似文献
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Evaluation of usage of virtual microscopy for the study of histology in the medical,dental, and veterinary undergraduate programs of a UK University
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Margaret K. Gatumu Frances M. MacMillan Philip D. Langton P. Max Headley Judy R. Harris 《Anatomical sciences education》2014,7(5):389-398
This article describes the introduction of a virtual microscope (VM) that has allowed preclinical histology teaching to be fashioned to better suit the needs of approximately 900 undergraduate students per year studying medicine, dentistry, or veterinary science at the University of Bristol, United Kingdom. Features of the VM implementation include: (1) the facility for students and teachers to make annotations on the digital slides; (2) in‐house development of VM‐based quizzes that are used for both formative and summative assessments; (3) archiving of teaching materials generated each year, enabling students to access their personalized learning resources throughout their programs; and (4) retention of light microscopy capability alongside the VM. Student feedback on the VM is particularly positive about its ease of use, the value of the annotation tool, the quizzes, and the accessibility of all components off‐campus. Analysis of login data indicates considerable, although variable, use of the VM by students outside timetabled teaching. The median number of annual logins per student account for every course exceeded the number of timetabled histology classes for that course (1.6–3.5 times). The total number of annual student logins across all cohorts increased from approximately 9,000 in the year 2007–2008 to 22,000 in the year 2010–2011. The implementation of the VM has improved teaching and learning in practical classes within the histology laboratory and facilitated consolidation and revision of material outside the laboratory. Discussion is provided of some novel strategies that capitalize on the benefits of introducing a VM, as well as strategies adopted to overcome some potential challenges. Anat Sci Educ 7: 389–398. © 2013 American Association of Anatomists. 相似文献
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The University of Florida offers an online professional practice Ed.D. focused on Educational Technology. Twenty-three students have completed professional practice dissertations and graduated since the program’s inception in 2008. The purpose of this article is to share what these dissertations have looked like and to begin a dialogue about professional practice dissertations completed in online educational technology programs. Specifically, we (1) provide an overview of different ways professional practice Ed.D. dissertations are structured, (2) share guiding principles for professional practice dissertations in our Ed.D. program, (3) analyze the ways in which these guiding principles played out in the dissertations and (4) discuss the implications of our analysis for our program and for other online professional practice programs in Educational Technology. 相似文献
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Margaret OBrien Caughy Keng-Yen Huang Therese Miller Janice L. Genevro 《Early childhood research quarterly》2004,19(4):611-630
The Healthy Steps for Young Children Program (HS) is designed to provide support for new parents through the pediatrician's office. We present findings of the effect of HS on the quality of mother–child interaction, security of attachment, and child behavior using observational data from two of the HS sites that utilized a randomized treatment design. Results indicated that mothers participating in Healthy Steps were more likely to interact sensitively and appropriately than mothers in the comparison group at the second assessment point (age 34–37 months) but not at the first assessment point (age 16–18 months). There were no differences in child outcomes at either time point when the cross-sectional data were analyzed. However, the results of the longitudinal analysis (which included families who participated in the home observations at both Time 1 and Time 2) indicated that Healthy Steps participation was associated with greater security of attachment and fewer child behavior problems. 相似文献