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131.
JIANG Ren-jie QI Fei-hu XU Li WU Guo-rong ZHU Kai-hua 《浙江大学学报(A卷英文版)》2007,8(4):568-574
This paper proposes a learning-based method for text detection and text segmentation in natural scene images. First, the input image is decomposed into multiple connected-components (CCs) by Niblack clustering algorithm. Then all the CCs including text CCs and non-text CCs are verified on their text features by a 2-stage classification module, where most non-text CCs are discarded by an attentional cascade classifier and remaining CCs are further verified by an SVM. All the accepted CCs are output to result in text only binary image. Experiments with many images in different scenes showed satisfactory performance of our proposed method. 相似文献
132.
K. R. Shivanna 《Resonance》2016,21(11):1007-1018
After the pollen grain reaches the stigma through outsourced agents (pollinators), the next step before fertilization is to select the right type of pollen. Similar to a marriage in human beings, fiowering plants also have evolved elaborate screening process to select the right pollen grains and to reject the wrong ones. Even after initial screening for the right pollen, the pistil imposes a tough competition amongst them, comparable to a swayamvara of Indian mythology, to select the best available pollen. Flowering plants have evolved into a matriarchal society. The selection of the male partner is totally the prerogative of the mother (pistil); the boy (pollen grain) and the girl (ovule) has no say in this selection. 相似文献
133.
Clifford J. Mallett Tony Rossi Steven B. Rynne Richard Tinning 《Physical Education & Sport Pedagogy》2016,21(1):24-39
Background and Purpose: Given the turbulent and highly contested environment in which professional coaches work, a prime concern to coach developers is how coaches learn their craft. Understanding the learning and development of senior coaches (SCs) and assistant coaches (ACs) in the Australian Football League (AFL – the peak organisation for Australian Rules Football) is important to better develop the next generation of performance coaches. Hence the focus of this research was to examine the learning of SC and AC in the AFL. Fundamental to this research was an understanding that the AFL and each club within the league be regarded as learning organisations and workplaces with their own learning cultures where learning takes place. The purpose of this paper was to examine the learning culture for AFL coaches.Method: Five SCs, 6 ACs, and 5 administrators (4 of whom were former coaches) at 11 of the 16 AFL clubs were recruited for the research project. First, demographic data were collected for each participant (e.g. age, playing and coaching experience, development and coach development activities). Second, all participants were involved in one semi-structured interview of between 45 and 90 minutes duration. An interpretative (hierarchical content) analysis of the interview data was conducted to identify key emergent themes.Results: Learning was central to AFL coaches becoming a SC. Nevertheless, coaches reported a sense of isolation and a lack of support in developing their craft within their particular learning culture. These coaches developed a unique dynamic social network (DSN) that involved episodic contact with a number of respected confidantes often from diverse fields (used here in the Bourdieuian sense) in developing their coaching craft. Although there were some opportunities in their workplace, much of their learning was unmediated by others, underscoring the importance of their agentic engagement in limited workplace affordances.Conclusion: The variety of people accessed for the purposes of learning (often beyond the immediate workplace) and the long time taken to establish networks of supporters meant that a new way of describing the social networks of AFL coaches was needed; DSN. However, despite the acknowledged utility of learning from others, all coaches reported some sense of isolation in their learning. The sense of isolation brought about by professional volatility in high-performance Australian Football offers an alternative view on Hodkinson, Biesta and James' attempt in overcoming dualisms in learning. 相似文献
134.
135.
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
136.
A non-rotational (NR) shot is now a well-known scoring move in soccer. To execute the NR shot, it is necessary to deprive the ball of any rotational forces during the impact phase. To execute the NR shot, it is natural that the force vector acting from the foot would pass through the ball’s center of gravity; however, the coordinated motion of the lower limb joint’s angular displacement and the pelvis is still unclear. The aim of this study is to estimate the coordinated leg and pelvis motion during the NR shot as compared to that during instep kicking. Four right-leg dominant college league players were asked to perform a NR shot and an instep kick a total of 10 times each. Hip, knee, and ankle joint angular displacements in the sagittal plane and pelvis yaw and roll rotational motions during both types of kicks were calculated with 14 IR reflective markers using a 3D real-time motion analysis system with a 250-Hz sampling. The Euclidean distances of the joint space of the NR shot and the instep kick were also calculated to detect similarities in the coordinated motion of the lower limb. The results showed that the lower limb joint motions in the sagittal plane were not different; however, the pelvis roll and yaw motions were apparently different, and these phenomena could simulate a pendulum motion with changes in both the vertical and horizontal displacements. These results suggest that the coordinated motion of the lower limb joint’s angular displacement shows high similarity between the NR shot and the instep kick, and the pelvis roll and yaw synchronized orientation is essential for achieving the NR shot. 相似文献
137.
Judy C. Stribling Joshua E. Richardson 《Journal of the Medical Library Association》2016,104(2):159-164
Objective
The authors explored the feasibility and possible benefit of tablet-based educational materials for patients in clinic waiting areas.Methods
We distributed eight tablets preloaded with diagnosis-relevant information in two clinic waiting areas. Patients were surveyed about satisfaction, usability, and effects on learning. Technical issues were resolved.Results
Thirty-seven of forty patients completed the survey. On average, the patients were satisfied in all categories.Conclusions
Placing tablet-based educational materials in clinic waiting areas is relatively easy to implement. Patients using tablets reported satisfaction across three domains: usability, education, and satisfaction. 相似文献138.
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
139.
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
140.