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21.
Susan Dente Ross 《广播与电子媒介杂志》2013,57(2):254-270
Video market entry options available to telephone companies under the Telecommunications Act of 1996 have First Amendment implications that will affect the constitutional value of telephone video. These entry options impose regulatory constraints upon providers and differ in potentials for provider speech, speaker access, and content diversity. The author concludes that the Act's open video system option best advances First Amendment interests in increased diversity of and access to speech. 相似文献
22.
Software engineering education can be viewed as a challenging task. Computer science students tend to focus on the programming aspects of a project, and take a “hacking approach” to completing a project, rather than viewing the process. Our course material includes teaching the Personal Software Process (PSP). Students are required to produce defect and effort metrics, as well as project summary reports. Tools to assist information recording and production of reports are difficult for students to access. The cost in terms of financial and learning time is usually too high at the educational level to justify using commercial tools that are available for the professional software engineer. We have developed a tool—Personal Assistant for Software Engineers—to aid students in the learning of the PSP. The tool has been successfully used in four subjects for a semester. Following feedback and evaluation, it has been redesigned, and is currently in stage two. The tool has been useful for students, and has automated the previous manual process of producing time and defect reports, along with project summaries, thus allowing them to focus on the meaning of the information. 相似文献
23.
Abstract Using the stimulated recall of instruction methodology, we interviewed teachers and students at risk for referral to special education about their perceptions, judgments, and decision making during the course of instruction. The results of the teacher interviews suggest that teachers respond to complex collections of student cues in their decision making about students. Teachers described themselves as more frequently monitoring the at‐risk students, although their attempts to modify instruction consisted primarily of attempts to motivate these students. The at‐risk students indicated awareness that they are experiencing difficulty in class, had somewhat less understanding of how teachers attempt to help them, and responded with anger and frustration to their learning problems. 相似文献
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The application of advanced engineering to tennis racket design has influenced the nature of the sport. As a result, the International Tennis Federation has established rules to limit performance, with the aim of protecting the nature of the game. This paper illustrates how changes to the racket affect the player-racket system. The review integrates engineering and biomechanical issues related to tennis racket performance, covering the biomechanical characteristics of tennis strokes, tennis racket performance, the effect of racket parameters on ball rebound and biomechanical interactions. Racket properties influence the rebound of the ball. Ball rebound speed increases with frame stiffness and as string tension decreases. Reducing inter-string contacting forces increases rebound topspin. Historical trends and predictive modelling indicate swingweights of around 0.030–0.035 kg/m2 are best for high ball speed and accuracy. To fully understand the effect of their design changes, engineers should use impact conditions in their experiments, or models, which reflect those of actual tennis strokes. Sports engineers, therefore, benefit from working closely with biomechanists to ensure realistic impact conditions. 相似文献
27.
Jiří Baláš David Giles Jan Kodejška Michaela Panáčková Simon Fryer 《European Journal of Sport Science》2016,16(7):764-772
This study aimed to (1) evaluate the effect of hand shaking during recovery phases of intermittent testing on the time–force characteristics of performance and muscle oxygenation, and (2) assess inter-individual variability in the time to achieve the target force during intermittent testing in rock climbers. Twenty-two participants undertook three finger flexor endurance tests at 60% of their maximal voluntary contraction until failure. Performances of a sustained contraction and two intermittent contractions, each with different recovery strategies, were analysed by time–force parameters and near-infrared spectroscopy. Recovery with shaking of the forearm beside the body led to a significantly greater intermittent test time (↑ 22%, P?.05), force–time integral (↑ 28%, P?.05) and faster muscle re-oxygenation (↑ 32%, P?.05), when compared to the hand over hold condition. Further, the ratio of intermittent to continuous test time distinguished specific aerobic muscular adaptations among sport climbers (2.02), boulderers (1.74) and lower grade climbers (1.25). Lower grade climbers and boulderers produced shorter duration contractions due to the slower development of target force during the intermittent test, indicating worse kinaesthetic differentiation. Both the type of recovery and climbing discipline determined muscle re-oxygenation and intermittent performance in rock climbers. 相似文献
28.
Robert Reed Simon Adrian Jobson Louis Passfield 《European Journal of Sport Science》2016,16(8):903-911
The cadence that maximises power output developed at the crank by an individual cyclist is conventionally determined using a laboratory test. The purpose of this study was two-fold: (i) to show that such a cadence, which we call the optimal cadence, can be determined using power output, heart-rate, and cadence measured in the field and (ii) to describe methodology to do so. For an individual cyclist's sessions, power output is related to cadence and the elicited heart-rate using a non-linear regression model. Optimal cadences are found for two riders (83 and 70 revolutions per minute, respectively); these cadences are similar to the riders’ preferred cadences (82–92?rpm and 65–75?rpm). Power output reduces by approximately 6% for cadences 20?rpm above or below optimum. Our methodology can be used by a rider to determine an optimal cadence without laboratory testing intervention: the rider will need to collect power output, heart-rate, and cadence measurements from training and racing sessions over an extended period (>6 months); ride at a range of cadences within those sessions; and calculate his/her optimal cadence using the methodology described or a software tool that implements it. 相似文献
29.
Academic libraries are one of the most important sources of “on the job” training for future library instructors. Librarians who supervise and assess these future library instructors (often in graduate assistant positions) often choose to provide observations and feedback each semester to these instructors in training. Scholarly literature, however, provides little information on whether this system helps graduate assistants to develop as teachers. The authors of this article assessed graduate assistants’ performance as teachers over three semesters using a system of observation and self-assessment. They analyzed both patterns and areas of growth and discuss the strengths and weaknesses of this system. 相似文献
30.
“I Heard it through the Grapevine”: Doctoral Student Socialization in Chemistry and History 总被引:2,自引:0,他引:2
Susan K. Gardner 《Higher Education》2007,54(5):723-740
Twenty doctoral students in the disciplines of chemistry and history were interviewed to better understand the socialization
processes that influence their success and how these processes differ by year in the degree program and disciplinary culture.
Five major themes emerged describing these socialization processes and how they facilitate or impede degree success, including
Ambiguity, describing the programmatic guidelines and expectations that surrounded much of the students’ experience; Balance,
pointing to the students’ need to balance graduate school responsibilities along with external relationships and demands;
Independence, describing the students’ desire to find equilibrium as they transitioned to the role of independent scholar;
Development, highlighting the significant cognitive, personal, and professional development that occurs in these students’
graduate experience; and Support, describing the faculty, peer, and financial support needed for the students’ success in
their degree programs. Suggestions for policy, practice, and further research are discussed. 相似文献