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21.
Collecting samples is a challenging task for face recognition, especially for some real-world applications such as law enhancement and ID card identification, where there is usually single sample per person (SSPS) used to train a face recognition system. To extract discriminative features from the small size samples, in this paper we propose virtual samples via bidirectional feature selection with global and local structure preservation (VS-BFS-GL) to augment the number of training samples. In VS-BFS-GL, bidirectional feature selection is developed, which introduces L2,1 norm to explore the face variations from both horizontal and vertical directions. Further, to include more variations in the virtual images, the global structure information and sample-specified local structure information of the SSPP training set are considered. By integrating bidirectional feature selection, global and local structure, the limited training samples are fully utilized and more knowledge are mined. To further improve the effectiveness of VS-BFS-GL, an auxiliary database containing different face variations can be used to explore the local structure information. We extensively evaluated the proposed approach on AR and FERET database. The promising recognition results demonstrate that VS-BFS-GL is robust to expression, pose and partial occlusion variations in the faces.  相似文献   
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In this article we report the results of a study conducted to investigate the learning dynamics of three-ball juggling from the perspective of frequency locking. Based on the Farey sequence, we predicted that four stable coordination patterns, corresponding to dwell ratios of 0.83, 0.75, 0.67, and 0.50, would appear in the learning process. We examined the learning process in terms of task performance, taking into account individual differences in the amount of learning. We observed that the participants acquired individual-specific coordination patterns in a relatively early stage of learning, and that those coordination patterns were preserved in subsequent learning, even though performance in terms of number of successful consecutive throws increased substantially. This increase appeared to be related to a reduction in spatial variability of the juggling movements. Finally, the observed coordination patterns were in agreement with the predicted patterns, with the proviso that the pattern corresponding to a dwell ratio of 0.50 was not realized and only a hint of evidence was found for the dwell ratio of 0.67. This implies that the dwell ratios of 0.83 and 0.75 in particular exhibited a stable coordination structure due to strong frequency locking between the temporal variables of juggling.  相似文献   
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The aim of this study was to evaluate stride-to-stride variability of the lower extremity during walking in individuals with and without chronic ankle instability (CAI) using a nonlinear analysis. Twenty-five participants with self-reported CAI and 27 healthy control participants volunteered for this study. Participants walked on a motor-driven treadmill for 3 min at their selected speed. Lower extremity kinematics in the sagittal and frontal planes were recorded using a passive retroreflective marker motion capture system. The temporal structure of walking variability was analyzed with sample entropy (SampEn). The CAI group produced lower SampEn values in frontal-plane ankle kinematics compared to the control group (P = .04). No significant group differences were observed for SampEn values of other kinematics (P > .05). Participants with CAI demonstrated less stride-to-stride variability of the frontal plane ankle kinematics compared to healthy controls. Decreased variability of walking patterns demonstrated by participants with CAI indicates that the presence of CAI may be associated with a less adaptable sensorimotor system to environmental changes. The altered sensorimotor function associated with CAI may be targets for clinical interventions, and it is critical to explore how interventions protocols affect sensorimotor system function.  相似文献   
25.
Based on Jung's definition of archetype the concept 'archetypal story pattern' is developed as well as a research method drawing on narrative analysis and biographical research to identify these archetypal story patterns in life stories. Jung pointed out that personal myths, archetypal patterns found, e.g., in mythology, can govern the life course of individuals unconsciously. In the Theory of Narrative Identity comparable concepts have been mentioned but were never fully developed. In my research I try to combine Jung's concept of the archetype with the elaborated methodology of narrative analysis. Archetypes can manifest as narratives and the identity construction of a person via narrating the life story can be influenced or even totally structured by archetypal stories which give a specific form as well as a specific meaning to the person's identity. The method of extracting an underlying archetypal pattern from an autobiographical narrative is demonstrated. The results of the research on 20 autobiographical interviews and the inherent archetypal patterns are summarized. The major aim of this paper is to describe in detail the application of a well established method of the social sciences on a key concept of Jungian psychology to show that these concepts can be integrated into recent research frameworks of academic sciences. On the other hand it shows that Jungian concepts can be investigated through established and well defined research methods in empirical research settings.  相似文献   
26.
Computational metaphors for determining the orientation of planar surfaces represented in line drawings have exploited a postulate that often surfaces are rectangular. Previous research implies that people follow such logic with real surfaces in ecological viewing. However, this research is problematic methodologically and some research does not directly address the issue. The stimuli used in this study were rectangular and trapezoidal; the latter shape was used to mislead with regard to orientation under the rectangularity postulate. Viewing conditions were monocular and binocular, with and without observer movement. The results suggest that the rectangularity postulate was important under stationary monocular viewing but diminished with movement and was not apparent during binocular viewing. General arguments about the importance of secondary depth cues in ecological viewing are developed.  相似文献   
27.
Despite the recent advances in the field of coordination dynamics addressing the interplay of constraints of different natures in the emergence of human coordination, F. Mechsner (2004) invites us to revive hierarchical and dichotomous thinking by offering again his exclusive position that coordinated movements are (purely) perceptual-cognitive/psychological in nature. In this comment, the authors address a number of theoretical and methodological issues that might potentially puzzle the readers of Mechsner's article. They contend that the dichotomy proposed by Mechsner (i.e., perceptual-cognitive vs. motor) constitutes a restrictive framework for understanding human coordination.  相似文献   
28.
We tested the hypothesis that “good feelings”—the central element of subjective well-being—are associated with interdependence and interpersonal engagement of the self in Japan, but with independence and interpersonal disengagement of the self in the United States. Japanese and American college students (total N = 913) reported how frequently they experienced various emotional states in daily life. In support of the hypothesis, the reported frequency of general positive emotions (e.g. calm, elated) was most closely associated with the reported frequency of interpersonally engaged positive emotions (e.g. friendly feelings) in Japan, but with the reported frequency of interpersonally disengaged positive emotions (e.g. pride) in the United States. Further, for Americans the reported frequency of experience was considerably higher for positive emotions than for negative emotions, but for Japanese it was higher for engaged emotions than for disengaged emotions. Implications for cultural constructions of emotion in general and subjective well-being in particular are discussed.  相似文献   
29.
The current study aims to investigate the relationship between right, wrong and missing answers to cognitive test items (test-taking patterns) in the context of the Flynn Effect (FE). We compare two cohorts of Estonian students (1933/36, n = 890; 2006, n = 913) using an Estonian adaptation of the National Intelligence Tests and document three simultaneous trends: fewer missing answers (− 1 Cohen's d averaged over subtests), and a rise in the number of right and wrong answers to the subtests (average ds of .86 and .30, respectively). In the Arithmetical Reasoning and Vocabulary subtests, adjustments for false-positive answers (the number of right minus the number of wrong answers) reduced the size of the Flynn Effect by half. These subtests were supposed to be high g-loading subtests. Our conclusion is that rapid guessing has risen over time and influenced tests scores more strongly over the years. The FE is partly explained by changes in test-taking behavior over time.  相似文献   
30.
It has been hypothesized that a local processing bias underlies overall visuospatial impairments in Williams syndrome (WS). However, recent studies have challenged this hypothesis by providing evidence against a local processing bias at the perceptual level. The aim of the present study was to further examine drawing and perceptual skills in children with WS using closely matched-hierarchical stimuli. In the drawing task children with WS exhibited a local processing bias. However, no significant preferential bias was found in the perceptual task. This indicates that children with WS do not systematically present a preferential bias for local information. Taken together the findings of the present study suggest that perceptual processing deficits per se are unlikely to explain local processing biases in visuoconstructive tasks often described in people with WS.  相似文献   
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