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941.
Margaret Mackey 《Children‘s Literature in Education》2011,42(3):181-183
942.
Samiyyah Black Carolina Estrada Mirza Carolina de la Fuente Ashley Orozco Andrew Trabazo Sofia de la Vega 《Journalism Practice》2019,13(1):35-51
This article examines talks given by 12 female media professionals at a Southern US university’s center on women in communication between 2013 and 2015 to identify the influence of hegemonic masculinity in industry speak about women and professionalism in the fields of journalism, advertising, and public relations. This paper applies a feminist critique of discussions about “work–life balance,” “leaning in,” “emotion,” and language about the role of technology and innovation in women’s careers, to argue that inherent in these discussions about media professionalism are traits that perpetuate binary notions of feminine–masculine traits of the workplace. As a whole, these messages fail to account for notions of intersectionality and perpetuate inequality and masculine power for future professionals. 相似文献
943.
944.
Commonly used technical anatomy and physiology (A&P) terms are predominantly rooted in Latin and Greek vocabulary, so it is commonly inferred that a solid grounding in Latin and Greek roots of medical terminology will improve student learning in anatomy and related disciplines. This study examines the association of etymological knowledge of A&P terms and A&P course performance among 446 undergraduates in their first semester of the study of human gross anatomy and physiology, with a more detailed analysis of the characteristics of 52 students who filled out surveys about their prior knowledge and experiences related to medicine or anatomy. In both data sets, there was only a weak positive correlation between the performance on a quiz of Latin and Greek medical terms and the students' performance on regular assignments. The presumption that familiarity with Latin and Greek word roots has a strong influence on successful learning of anatomy is not supported by these data. Future research should address whether or not there are particular skills associated with using etymological knowledge in improving A&P course performance. 相似文献
945.
Chao Ai Wei Gao Lijuan Chen Jiawei Guo Xiangdong Kong Andrew Plummer 《Journal of The Franklin Institute》2021,358(1):296-320
The requirement for An electrical grid-connected wind turbine is that the synchronous generator speed is stable within a required speed range for the electrical grid. In this paper, a hydraulic wind turbine (HWT) system is considered, and the working principle and working conditions of the HWT are introduced. A novel speed control method is proposed in this paper, using both a proportional flow control valve and a variable displacement motor, which are adjusted in combination to control the speed of the HWT. By establishing a state space model of the HWT and solving the nonlinear system with a feedback linearization method, a bivariate tracking controller is constructed to realize accurate speed control under fluctuating wind speed and the load disturbance conditions. The effectiveness of the control method is verified by simulation, but experimental results highlight problems with the method. The theoretical controller is simplified to reduce sensitivity to measurement noise and modeling error. The control effect has been improved to some extent, but it is limited. Based on these results, combined with the sliding mode variable structure control method and the feedback linearization method to solve the problem of measurement noise and modeling error, and the effectiveness of the control law is finally verified experimentally. It lays a theoretical foundation for the practical application of HWT. 相似文献
946.
Pascual Marqués-Bruna 《Sports Engineering》2011,13(4):195-204
This study examined aerodynamic properties and boundary layer stability in five cambered airfoils operating at the low Reynolds
numbers encountered in motor racing. Numerical modelling was carried out in the flow regime characterised by Reynolds numbers
0.82–1.29 × 106. The design Reynolds number of 3 × 106 was used as a reference. Aerodynamics variables were computed using AeroFoil 2.2 software, which uses the vortex panel method
and integral boundary layer equations. Validation of AeroFoil 2.2 software showed very good agreement between calculated aerodynamic
coefficients and wind tunnel experimental data. Drag polars, lift/drag ratio, pitching moment coefficient, chordwise distributions
(surface velocity ratio, pressure coefficient and boundary layer thickness), stagnation point, and boundary layer transition
and separation were obtained at angles of attack from −4° to 12°. The NASA NLF(1)-0414F airfoil offers versatility for motor
racing with a wide low-drag bucket, low minimum profile drag, high lift/drag ratio, laminar flow up to 0.7 chord, rapid concave
pressure recovery, high resultant pressure coefficient and stall resistance at low Reynolds numbers. The findings have implications
for the design of race car wings. 相似文献
947.
Test procedures and their accuracy in determining critical fall height (CFH) on sporting grounds are paramount to player safety.
The procedure currently adopted for synthetic turf in Australian football [1] consists of four consecutive drops at various drop heights at three test locations on the sample. The quantity and packing
of the infill in third-generation turf and the pooling effect of the rubber particles with consecutive drops suggests that
the current standard protocol may need re-assessment. Therefore, the purpose of this pilot study was to investigate whether
current methods of testing for CFH are appropriate for third-generation synthetic turf or whether an alternative or adapted
method needs to be developed. CFH was measured, using a HISUN Uniaxe-II Impact Tester, on 12 combinations of synthetic turf
samples (four different products with three shock pad options). Three conditions were investigated on each sample; the existing
protocol; an alternative 12 single-drop protocol and four single drops from the CFH determined from the existing protocol.
A significant difference was found for both absolute and percentage difference between the existing and 12 single-drop protocol,
with p = 0.001 and t = 4.33 and p < 0.001 and t = 6.03, respectively. There was also a significant difference between the CFH reached with and without a shock pad for both
the existing protocol and the 12 single-drop protocol. The results of this pilot study demonstrate that differences do occur
with alterations to the existing protocol and highlight the need for a more detailed characterisation of testing methods on
third-generation synthetic turf and the response of surfaces to them. 相似文献
948.
A number of recent studies have measured the extent and timing of segment rotation during the golf swing. A promising technique,
instantaneous screw axis (ISA) theory, could provide a better expression of segment rotation. In Part 1 of this two-part study,
the objectives are to identify the ISA of the pelvis, shoulders and left arm during the downswing, compute segment angular
velocity relative to that segment’s ISA and verify that ISA theory is a valid tool to analyse segment rotation during the
golf swing. Results indicate that for all subjects, at least 71% of marker velocity is a result of rotation about their respective
ISA, when averaging results over the duration of the downswing, confirming that motion is primarily rotational. Furthermore,
ISA position and orientation of each segment approaches, on average, the expected gross axis of rotation, confirming that
motion about the ISA is representative of joint motion. 相似文献
949.
Kevin King N. C. Perkins Hugh Churchill Ryan McGinnis Ryan Doss Ron Hickland 《Sports Engineering》2011,13(2):95-104
This paper presents a novel sensor technology to deduce the dynamics of a bowling ball. The sensor, a miniature wireless inertial
measurement unit (IMU), incorporates MEMS accelerometers and angular rate gyros, a microcontroller, a low power RF transceiver,
and a rechargeable battery. When embedded in a bowling ball, the IMU transmits the acceleration and angular velocity data
that define the dynamics of the ball starting with the bowler’s delivery and its motion in the lane. Example results from
professional bowlers illustrate how this technology can be used to assess bowler skill and ball performance. For instance,
the IMU accurately measures the spin dynamics of the ball which are crucial to develop the ball “hook.” An analysis of ball
dynamics in the lane is distilled to a measurable “hook potential” metric for further assessing bowler skill. Finally, the
sensor presented herein is believed to be the world’s smallest, wireless IMU. This highly miniaturized and wireless design
will enable parallel training systems for many sports, including basketball, baseball, crew, cricket, golf, fly fishing, soccer,
softball, tennis, rowing, among others. 相似文献
950.
P-selectin, a cell adhesion molecule is elevated in many inflammatory conditions including preeclampsia which is characterized
by generalized endothelial dysfunction and vasoconstriction presumably due to free radicals or mediators released by defective
placentation. Vitamin E has been documented to protect cell membranes from oxidative damage and also decrease platelet aggregation.
The role of vitamin E in pre-eclampsia is contradictory and hence the study was undertaken. Soluble P-selectin was measured
by ELISA and Vitamin-E levels in plasma was estimated spectrofluorometrically. In our study the effect of supplementation
of 400 IU/day of Vitamin E (a-tocopheryl acetate) to patients of pre-eclampsia showed significant decreased levels of soluble
P-selectin by 2nd week as compared to patients given placebo (P = 0.005). In this short period of study no direct correlations were observed between Vitamin E or P-selectin levels with
blood pressure as well as with proteinuria. Future studies may focus on the effect of a-tocopheryl acetate or the phosphate
form of Vitamin-E, recently proposed to be the more active form on other inflammatory markers like IL-6, an important stimuli
of P-selectin release in pre-eclampsia. 相似文献