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991.
Tiffany A. Moisan Robert N. Swift Brian A. Campbell James K. Yungel Matthew A. Linkswiler Jessica K. Nolan 《Journal of Science Education and Technology》2008,17(3):252-261
Recently there have been newly launched ocean color satellites which target the coastlines at unprecedented scales. Science
education curricula can benefit from the provision of small low-cost spectroradiometers and curriculum supplemental materials
that can be incorporated in a “hands on” teaching approach to explain and demonstrate remote sensing reflectance principles.
A lesson in which a progressive set of spectral measurements of familiar and unfamiliar objects and natural waters acquired
by students using a small fiberoptic probe and spectroradiometer is presented. This lesson has a dual purpose. The first is
to serve as a teaching supplement to high school science curricula while paralleling the National Science Education Standards
(NSES) for NASA ocean color products, as well as other satellite ocean products such as GLI and MERIS. The second is to focus
on the scientific goals of the graduate-school bound undergraduate student by providing a fundamental understanding of the
principles of passive ocean color remote sensing that will perhaps nurture the interest of some students toward research involving
utilization of NASA’s Earth science data products. We intend to have these spectroradiometers readily available for use by
teachers in the Earth sciences through a publicly available technology library. 相似文献
992.
993.
Training Needs Analysis and Evaluation for New Technologies Through the Use of Problem‐based Inquiry
ABSTRACT The analysis of calls to a help desk, in this case calls to a computer help desk, can serve as a rich source of information on the real world problems that individuals are having with the implementation of a new technology. Thus, we propose that an analysis of help desk calls, a form of problem‐based inquiry, can serve as a fast and low cost means of both analyzing training needs and evaluating training. We illustrate the use of problem‐based inquiry through a case study of the analysis of help desk calls made after the delivery of a training program that served to introduce a new type of document management system in a professional services firm. Based on the analysis of help desk calls it should be possible to modify future training so as to enhance transfer to the job environment. 相似文献
994.
995.
Reliability and construct validity of soccer skills tests that measure passing, shooting, and dribbling 总被引:1,自引:1,他引:0
In this study, we examined the reliability and construct validity of new soccer skills tests. Twenty soccer players (10 professional and 10 recreational) repeated trials of passing, shooting, and dribbling skills on different days. Passing and shooting skills required players to kick a moving ball, delivered at constant speed, towards one of four randomly determined targets. Dribbling required players to negotiate seven cones over 20?m. Each trial consisted of 28 passes, 8 shots, and 10 dribbles. Ball speed, precision, and success were determined for all tests using video analysis. Systematic bias was small (<9% in all measures) and all outcome measures were similar between trials. Test-retest reliability statistics were as follows: ball speed (passing, shooting, dribbling; coefficient of variation [CV]: 6.5%, 6.9%, 2.4%; ratio limits of agreement [RLOA]: 0.958?×/÷ 1.091, 0.990?×/÷ 1.107, 0.993?×/÷ 1.039), precision (passing, shooting, dribbling; CV: 10.0%, 23.5%, 4.6%; RLOA: 0.956?×/÷ 1.147, 1.030?×/÷ 1.356, 1.000?×/÷ 1.068), and success (passing, shooting, dribbling; CV: 11.7%, 14.4%, 2.2%; RLOA: 1.017?×/÷ 1.191, 0.913?×/÷ 1.265, 0.996?×/÷ 1.035). Professional players performed better than recreational players in at least one outcome measure for all skills. These findings demonstrate the reliability and validity of new soccer skill protocols. 相似文献
996.
Mills C Yeadon MR Pain MT 《Sports biomechanics / International Society of Biomechanics in Sports》2010,9(3):153-164
This study investigated how changes in the material properties of a landing mat could minimise ground reaction forces (GRF) and internal loading on a gymnast during landing. A multi-layer model of a gymnastics competition landing mat and a subject-specific seven-link wobbling mass model of a gymnast were developed to address this aim. Landing mat properties (stiffness and damping) were optimised using a Simplex algorithm to minimise GRF and internal loading. The optimisation of the landing mat parameters was characterised by minimal changes to the mat's stiffness (<0.5%) but increased damping (272%) compared to the competition landing mat. Changes to the landing mat resulted in reduced peak vertical and horizontal GRF and reduced bone bending moments in the shank and thigh compared to a matching simulation. Peak bone bending moments within the thigh and shank were reduced by 6% from 321.5 Nm to 302.5Nm and GRF by 12% from 8626 N to 7552 N when compared to a matching simulation. The reduction in these forces may help to reduce the risk of bone fracture injury associated with a single landing and reduce the risk of a chronic injury such as a stress fracture. 相似文献
997.
This case concerns the fictional city of Urbanville, the state capital of Northern Australia, a pseudonym for one of Australia's eight States and Territories, where the State and municipal governments have decided to invest $600 M in the construction of a new sport stadium. The case explores the question of how the stadium will be governed once it has been constructed. The case outlines the key issues and challenges posed by Urbanville's existing sport stadia infrastructure; current issues among stakeholders and their use of existing stadia in Urbanville; and possible choices for the governance arrangements of the new stadium. 相似文献
998.
Isabel T. Gutiérrez David Menendez Matthew J. Jiang Iseli G. Hernandez Peggy Miller Karl S. Rosengren 《Child development》2020,91(2):e491-e511
A mixed-method approach was used to explore parent and child perspectives on death in Mexico. Parents’ and children’s death-related experiences and understanding of death were examined. While all children in this sample displayed a biological understanding of death, older children were less likely to endorse that all living things die. Children also displayed coexistence of beliefs related to death that can be attributed to both their biological and spiritual understanding of death. We also found that older children were more likely to report that a child should feel sad following the death of a loved one. These findings highlight how cultural practices shape the development of cognitive and affective processes related to death. 相似文献
999.
Joshua M. Rosenberg Joshua W. Reid Elizabeth B. Dyer Matthew J. Koehler Christian Fischer Thomas J. McKenna 《科学教学研究杂志》2020,57(9):1322-1355
The Next Generation Science Standards (NGSS) chat (#NGSSchat) is a social media-based professional network used to discuss topics related to the NGSS in the United States. While successful reforms involve and coordinate the work of multiple stakeholders, recent research points out a striking lack of coordination between the individuals working in different educational roles—to the detriment of intended changes in the system. In this study, we analyzed more than 7,000 posts from individuals participating in #NGSSchat on Twitter (n = 247) during 2 years of 1-hr synchronous discussions. We studied the depth and types of conversations that took place, the extent to which the involvement of teachers, administrators, researchers, and organizations was balanced, and what explains participation in the network over time. Using a mixed-methods approach involving social network analysis, we found that conversations were primarily transactional, or social, and substantive, or providing opportunities for sense-making about the standards or for participants to transform their practice and that individuals from diverse roles participated, with teachers comprising the plurality of those involved. Additionally, researchers, administrators, and teachers were the most active in the network, with no differences in both initiating, or sending, and being the recipients of, or receiving, replies as a part of conversations. Finally, we found that being a teacher or administrator, as well as receiving replies from individuals who were important in the network, were positively related to sustained involvement in the network in the following year. We discuss how #NGSSchat—as a social media-based professional network—demonstrates similar features in other effective networks, and how social media-based networks invite new visions for how to implement ambitious, large-scale changes in science education. 相似文献
1000.
This study examined the usefulness of applying the Rasch rating scale model (Andrich, 1978) to high school grade data. ACT Assessment test scores (English, Mathematics, Reading, and Science Reasoning) were used as "common items" to adjust for different grading standards in individual high school courses both within and across schools. This scaling approach yielded an ACT Assessment-adjusted high school grade point average (AA-HSGPA) on a common scale across high schools and cohorts within a large public university. AA-HSGPA was a better predictor of first-year college grade point average (CGPA) than the regular high school grade point average. The best model for predicting CGPA included both the ACT composite score and AA-HSGPA. 相似文献