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221.
David S. Haydon Ross A. Pinder Paul N. Grimshaw William S. P. Robertson 《Sports Engineering》2016,19(3):177-184
Limited recommendations of wheelchair configurations for court sports have been identified in the published literature. To accommodate the wide range of impairments in wheelchair rugby, players are given a point score that reflects their impairment. Players have regularly been grouped as high-, mid-, or low-point players in research, with high-point players having greater levels of muscle function compared with other classifications. This research documented the wheelchair configurations of elite Australian wheelchair rugby players across classification groups. Significant differences (p < 0.05) were found for increased seat height and decreased seat depth for high-point players compared with low- and mid-point groups, respectively. Low-point players displayed reduced wheelchair mass compared with high- and mid-point players, as well as increased frame length. Camber angles showed no significant differences across the classification groups. The incorporation of anthropometric measures, such as the elbow angle at the top dead center, was also investigated. While elbow angle showed no significant differences, seat height-to-total arm length ratio was higher for high-point players. Participants also completed surveys detailing their perception of the effect of altering wheelchair configurations. It is suggested that wheelchair configurations should consider an individual’s anthropometrics, impairment, training history, and court role to promote optimal performance, with predictive modeling having the potential to reduce the associated time and cost. 相似文献
222.
Can a floating collection thrive in a large multicampus academic research library? Floating collections have been successful in public libraries for some time, but it is uncommon for academic libraries and unheard of for a large academic library system. This article will discuss the investigation into the feasibility of a floating collection at Penn State University Libraries, its implementation, and continuation for a period covering 2009 through 2015. Attaining the floating collection, limited to monographs in the general stacks of campus libraries, proved to be easier to implement than imagined and resulted in unintended benefits as well as some surprises. 相似文献
223.
With advanced prediction modes of intra prediction, intra coding of H.264/AVC offers significant coding gains compared with previous video coding standards. It uses an important tool called Lagrangian rate-distortion optimization (RDO) technique to decide the best coding mode for a block, but the computational burden is extremely high. In this paper, we proposed an improved fast intra prediction algorithm including block type selection and mode decision algorithm based on analysis of edge feature of a block. Our algorithm filters out unlikely block type and candidate modes to reduce the RDO calculations. Experimental results showed that the proposed algorithm can reduce the computation complexity of intra prediction from 52.90% to 56.31%, with 0.04 dB PSNR degradation and 2% increase of bit rate. 相似文献
224.
残障儿童的父母.是孩子一生最好的教育者,因为他们在孩子成长的过程中无私奉献,恪尽责任。对那些有残障儿童的家庭而言.“知识就是力量”这句话就是真理。这些家长需要掌握关于残障症状的特点、教育治疗方案和策略等信息,以提升日常生活质量。家长们也想知道什么样的服务最适合孩子.如何获得这些服务.如何定位家长角色以确保孩子的进步.[第一段] 相似文献
225.
A clinical task-based interview can be seen as a situation where the interviewer–interviewee interaction on a task is regulated
by a system of explicit and implicit norms, values, and rules. This paper describes how documenting and mapping triadic interaction
among the interviewer, the interviewee, and the knowledge negotiated can be used to increase procedural replicability of the
interview and accuracy of drawn conclusions about the interviewee’s thinking process. Excerpts from interviews with 25 inservice
mathematics teachers working on a task to make up a problem whose solution requires division of two fractions are discussed.
The excerpts illustrate the relationship between methodological decisions taken by the interviewer during the interview and
the applicability of the interview output to the research questions. A divergent analysis of the interviews with these teachers,
which spanned over two years and were conducted by four interviewers, is used to offer a framework for analyzing data collected
in clinical task-based interviews. 相似文献
226.
227.
1IntroductionBackground subtraction methods are extensively ex-ploited for moving object detection in videos in manyapplications ,such as traffic monitoring[1],human mo-tion capture[2]and video surveillance[3]. The centralidea behind such methods is to segment foreground ini mage sequences taken from a fixed camera by com-paring each newframe to a model of the scene back-ground . Therefore , correctly and efficiently modelingand updating the background model is one of the mostchallenging aspec… 相似文献
228.
Governmental consultation and advice on child abuse and neglect in the Netherlands started in 1972 as a two-year experiment with four offices for "confidential doctors" in four major cities of the country. After these two experimental years, a governmental institute for prevention of child abuse and neglect was organized. Over the ensuing decade the number of offices increased to ten, covering the whole country. The State Department of Welfare, Public Health, and Environment collected data from the confidential doctors and their coworkers every year. This study compares the data of the first year 1974 with those of 1983 in order to detect changing patterns over a 10-year period. The major changes are as follows: a threefold increase in cases, an extraordinary increase in cases of emotional maltreatment, an increase in detection of child fatalities but decrease in severity of physical abuse. Sexual abuse was hardly recognized in 1974 but gradually was recognized more frequently during the study decade and accounted for an alarming 7.2% of detected cases of maltreatment in 1983. No change was found in the social conditions of the family and the identity of the perpetrators--primarily fathers and/or mothers. A decrease was noted in the percentage of married parents. The increased percentage of single parents was primarily represented by mothers alone. An increase in the numbers of victims residing at home and a decrease in the need for children's homes as a temporary or permanent residence is attributed to aftercare. The discrepancy between the results of this voluntary notification system in the Netherlands and the results of a mandatory reporting system as used in the U.S.A. is still very high. The hope is that the government will decide to make reporting of maltreatment mandatory for everyone. 相似文献
229.
M.H. Matthews 《教育心理学》1987,7(2):77-90
Abstract This paper reports on a study set up to investigate the effects of gender related differences in home range behaviour on the acquision of spatial and environmental skills amongst a group of children aged 8 to 11. The population was divided to form two groups (A and B) of similar sex composition and environmental experience. The children were informed that the aim of the project was to construct a map of an unfamiliar area which they were to visit. The two groups were ‘primed’ about their task in different ways, with children in Group B undertaking a slightly more complex exercise. The results show that whilst ‘priming’ has the effect of reducing disjunction between the spatial capabilities of boys and girls on simpler tasks, when the exercise is complicated boys do much better than girls in all but one of the spatial assessments. Such evidence lends further support to those who argue that the more extensive movements of boys through the environment leads to superior spatial ability. The educational implications of the results are considered. 相似文献
230.
Rats were trained in a three-alternative spatial delayed matching-to-sample task in a starburst maze. Samples consisted of rewarded forced choices of one arm, and retention was indicated by rats’ returning to that arm after a 90-sec delay. If a rat made an error on its first choice, it was returned to the start compartment and allowed a second choice. Unlike in previous experiments with this task, all three arms were available during the animals’ second choices. The rats tended to perseverate in their second choices by returning to the arm that they had erroneously visited on their first choice. In Experiment 1, the accuracy of second choices following first-choice errors was below chance during the first block of sessions, when a 90-sec delay intervened between the first choice and the second choice, and at chance during the second block of sessions, when a short (5–6 see) delay intervened between first and second choices. In Experiment 2, long-delay and short-delay sessions were randomly presented to naive subjects. Similar results were obtained. In both experiments, the tendency to repeat the erroneous first choice was greater when long delays separated the two choices than when short delays were used. The results suggest that rats make their first-choice errors because they erroneously encode or remember the location of the sample and that they base their second choices on the same erroneous-memory. The increase in perseveration at long delays implies some kind of rehearsal-like mechanism that slows forgetting of the memory controlling the first choice. 相似文献