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41.
学生资助和高等教育机会均等--对中日美3国的比较分析   总被引:5,自引:0,他引:5  
世界各国的高等教育规模在不断扩大,但是低收入阶层的教育机会未必在同步增长,他们需要政府的资助。另一方面,教育规模的扩大又严重压迫着财政支出。各国都处在解决机会均等和财政负担的困境中。本文将讨论学生资助的相关理论,比较多样的资助制度,从中获得启示。  相似文献   
42.
本文比较了两种大学评价框架,即制度型大学评价和市场型大学评价.虽然这两类评价的共同特征和产生的因素都是基于学生、家长以及大学自身的要求,但是它们的目标、背景、指标却由于不同的评价目的而存在很大差异.  相似文献   
43.
Since its introduction, television has been the main channel of investment for advertisements in order to influence customers purchase behavior. Many have attributed the mere exposure effect as the source of influence in purchase intention and purchase decision; however, most of the studies of television advertisement effects are not only outdated, but their sample size is questionable and their environments do not reflect reality. With the advent of the internet, social media and new information technologies, many recent studies focus on the effects of online advertisement, meanwhile the investment in television advertisement still has not declined. In response to this, we applied machine learning algorithms SVM and XGBoost, as well as Logistic Regression, to construct a number of prediction models based on at-home advertisement exposure time and demographic data, examining the predictability of Actual Purchase and Purchase Intention behaviors of 3000 customers across 36 different products during the span of 3 months. If we were able to predict purchase behaviors with models based on exposure time more reliably than with models based on demographic data, the obvious strategy for businesses would be to increase the number of adverts. On the other hand, if models based on exposure time had unreliable predictability in contrast to models based on demographic data, doubts would surface about the effectiveness of the hard investment in television advertising. Based on our results, we found that models based on advert exposure time were consistently low in their predictability in comparison with models based on demographic data only, and with models based on both demographic data and exposure time data. We also found that there was not a statistically significant difference between these last two kinds of models. This suggests that advert exposure time has little to no effect in the short-term in increasing positive actual purchase behavior.  相似文献   
44.
This paper describes the use of Pareto-optimal solutions for the screw kick in rugby. We attempted to optimise the initial conditions for a screw kick. The optimisation was carried out using an elitist non-dominated sorting genetic algorithm. Distance achieved in flight is considered as an objective function, as well as the lateral deviation between the ball and the touchline, or the flight time. Six initial conditions were defined as control parameters: the magnitude of the velocity vector, the flight path angle, the azimuth angle, the spin rate, the pitch angle and the yaw angle. The results are summarised as follows: it is impossible for both objective functions to be satisfied simultaneously, although the greatest distance achieved in flight and the smallest value of the lateral deviation between the ball and the touchline, or the least flight time, is the ideal situation. This kind of conflicting solution is called a ‘Pareto-optimal solution’. The optimal kick in Pareto-optimal solutions made by the leg nearest the touchline produces a greater flight distance than the optimal kick in Pareto-optimal solutions made using the leg furthest from the touchline. The initial pitch angle, which is the angle between the longitudinal axis of the ball and the horizontal plane, should be comparable to or slightly greater than the initial flight path angle in order to satisfy the Pareto-optimal solutions.  相似文献   
45.
When the boundary layer of a sports ball undergoes the transition from laminar to turbulent flow, a drag crisis occurs whereby the drag coefficient (C d) rapidly decreases. However, the aerodynamic properties and boundary-layer dynamics of a soccer ball are not yet well understood. In this study we showed that the critical Reynolds number (Re crit) of soccer balls ranged from 2.2 × 105 to 3.0 × 105. Wind-tunnel testing, along with visualisation of the dynamics of the boundary layer and the trailing vortex of a ball in flight, demonstrated that both non-spinning and spinning (curved) balls had lowC d values in the super-critical region. In addition, theRe crit values of the soccer balls were lower than those of smooth spheres, ranging from ∼ 3.5 × 105 to 4.0 × 105, due to the effects of their panels. This indicated that the aerodynamic properties of a soccer ball were intermediate between those of a smooth ball and a golf ball. In a flow visualisation experiment, the separation point retreated and theC d decreased in a super-critical regime compared with those in a sub-critical regime, suggesting a phenomenon similar to that observed in other sports balls. With some non-spinning and spinning soccer balls, the wake varied over time. In general, the high-frequency component of an eddy dissipated, while the low-frequency component increased as the downstream vortex increased. The causes of the large-scale fluctuations in the vortex observed in the present study were unclear; however, it is possible that a ‘knuckle-ball effect’ of the non-rotating ball played a role in this phenomenon.  相似文献   
46.
In this paper we focus on individual coaching carried out by an external coach as a new pedagogical element that can impact doctoral students’ sense of progress in doctoral education. The study used a mixed-methods approach in that we draw on quantitative and qualitative data from the evaluation of a project on coaching doctoral students. We explore how coaching can contribute to the doctoral students’ development of a broad set of personal competences and suggest that coaching could work as a means to engender self-management and improve relational competences. The analysis of the participants’ self-reported gains from coaching show that doctoral students experience coaching as an effective method to support the doctoral study process. This study also provides preliminary empirical evidence that coaching of doctoral students can facilitate the doctoral study process so that the doctoral students experience an enhanced feeling of progress and that they can change their study behaviour in a positive direction. The study discusses the difference between coaching and supervision, for instance power imbalances and contrary to earlier research into coaching of doctoral students this study indicates that coaching can impact the supervisor–student relationship in a positive way.  相似文献   
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48.
Soccer kicks are characterized by segmental and joint rotations in multiple planes, where large discrepancies between two- and three-dimensional analyses for angular measurements of soccer kicks exist. The aim of this study was to clarify the differences in motions of the lower limbs and the pelvis required to achieve a shot without rotations as compared with an instep kick. Kinematic parameters obtained from non-rotational shots and instep kicks were analyzed using principal component analysis (PCA). The results clearly demonstrated that the PCA identified the differences in the instep kick and the non-rotational shot relative to the kinematic motions of the lower limbs and the pelvis. These findings suggest that the key issue for executing the NR shot is achieving a straight-line foot trajectory in the impact phase.  相似文献   
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