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Target Object (target + object)
Selected AbstractsDeformation Transfer to Multi-Component ObjectsCOMPUTER GRAPHICS FORUM, Issue 2 2010Kun Zhou Abstract We present a simple and effective algorithm to transfer deformation between surface meshes with multiple components. The algorithm automatically computes spatial relationships between components of the target object, builds correspondences between source and target, and finally transfers deformation of the source onto the target while preserving cohesion between the target's components. We demonstrate the versatility of our approach on various complex models. [source] The role of competition in word learning via referent selectionDEVELOPMENTAL SCIENCE, Issue 5 2010Jessica S. Horst Previous research suggests that competition among the objects present during referent selection influences young children's ability to learn words in fast mapping tasks. The present study systematically explored this issue with 30-month-old children. Children first received referent selection trials with a target object and either two, three or four competitor objects. Then, after a short delay, children were tested on their ability to retain the newly fast-mapped names. Overall, the number of competitors did not affect children's ability to form the initial name,object mappings. However, only children who encountered few competitors during referent selection demonstrated significant levels of retention. Results and implications are discussed in terms of the role of competition in studies of children's fast mapping. The relationship between referent selection and full word learning is also discussed. [source] Involvement of the human frontal eye field and multiple parietal areas in covert visual selection during conjunction searchEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 9 2000Tobias Donner Abstract Searching for a target object in a cluttered visual scene requires active visual attention if the target differs from distractors not by elementary visual features but rather by a feature conjunction. We used functional magnetic resonance imaging (fMRI) in human subjects to investigate the functional neuroanatomy of attentional mechanisms employed during conjunction search. In the experimental condition, subjects searched for a target defined by a conjunction of colour and orientation. In the baseline condition, subjects searched for a uniquely coloured target, regardless of its orientation. Eye movement recordings outside the scanner verified subjects' ability to maintain fixation during search. Reaction times indicated that the experimental condition was attentionally more demanding than the baseline condition. Differential activations between conditions were therefore ascribed to top-down modulation of neural activity. The frontal eye field, the ventral precentral sulcus and the following posterior parietal regions were consistently activated: (i) the postcentral sulcus; (ii) the posterior; and (iii) the anterior part of the intraparietal sulcus; and (iv) the junction of the intraparietal with the transverse occipital sulcus. Parietal regions were spatially distinct and displayed differential amplitudes of signal increase with a maximal amplitude in the posterior intraparietal sulcus. Less consistent activation was found in the lateral fusiform gyrus. These results suggest an involvement of the human frontal eye field in covert visual selection of potential targets during search. These results also provide evidence for a subdivision of posterior parietal cortex in multiple areas participating in covert visual selection, with a major contribution of the posterior intraparietal sulcus. [source] Texture-based parametric active contour for target detection and trackingINTERNATIONAL JOURNAL OF IMAGING SYSTEMS AND TECHNOLOGY, Issue 3 2009Ali Reza Vard Abstract In recent years, active contour models (ACM) have been considered as powerful tools for image segmentation and object tracking in computer vision and image processing applications. This article presents a new tracking method based on parametric active contour models. In the proposed method, a new pressure energy called "texture pressure energy" is added to the energy function of the parametric active contour model to detect and track a texture target object in a texture background. In this scheme, the texture features of the contour are calculated by a moment-based method. Then, by comparing these features with texture features of the target object, the contour curve is expanded or contracted to be adapted to the object boundaries. Experimental results show that the proposed method is more efficient and accurate in the tracking of objects compare to the traditional ones, when both object and background are textures in nature. © 2009 Wiley Periodicals, Inc. Int J Imaging Syst Technol, 19, 187,198, 2009 [source] Autonomous selection and modification of camera configurations using visibility and manipulability measuresJOURNAL OF FIELD ROBOTICS (FORMERLY JOURNAL OF ROBOTIC SYSTEMS), Issue 5 2002Gil W. Chu In this article, we present a camera control method in which the selection of an optimal camera position and the modification of camera configurations are accomplished according to changes in the surroundings. For the autonomous selection and modification of camera configurations during tasks, we consider the camera's visibility and the manipulator's manipulability. The visibility constraint guarantees that the whole of a target object can be "viewed" with no occlusions by the surroundings, and the manipulability constraint guarantees avoidance of the singular position of the manipulator and rapid modification of the camera position. By considering visibility and manipulability constraints simultaneously, we determine the optimal camera position and modify the camera configuration such that visual information for the target object can be obtained continuously during tasks. The results of simulations and experiments show that the active camera system with an eye-in-hand configuration can modify its configuration autonomously according to the motion of the surroundings by applying the proposed camera control method. © 2002 Wiley Periodicals, Inc. [source] The Infant as Onlooker: Learning From Emotional Reactions Observed in a Television ScenarioCHILD DEVELOPMENT, Issue 1 2003Donna L. Mumme Two studies investigated whether 10, and 12,month,olds can use televised emotional reactions to guide their behavior. Infants watched an actress orient toward 1 of 2 novel objects and react with neutral affect during baseline and with positive or negative affect during test. Infants then had 30 s to interact with the objects. In Study 1, 12,month,olds (N = 32) avoided the target object and showed increases in negative affect after observing the negative,emotion scenario. Twelve,month,olds' responses to positive vs. neutral signals did not differ significantly. In Study 2, 10,month,olds (N = 32) attended to the televised presentations but showed no consistent changes in their object interactions or affect. Thus, 12,month,olds used social information presented on television and associated emotional signals with the intended target. [source] Using dendronal signatures for feature extraction and retrievalINTERNATIONAL JOURNAL OF IMAGING SYSTEMS AND TECHNOLOGY, Issue 4 2000Luojian Chen A dendrone is a hierarchical thresholding structure that can be automatically generated from a complex image. The dendrone structure captures the connectedness of objects and subobjects during successive brightness thresholding. Based on connectedness and changes in intensity contours, dendronic representations of objects in images capture the coarse-to-fine unfolding of finer and finer detail, creating a unique signature for target objects that is invariant to lighting, scale, and placement of the object within the image. Subdendrones within the hierarchy are recognizable as objects within the picture. Complex composite images can be autonomously analyzed to determine if they contain the unique dendronic signatures of particular target objects of interest. In this paper, we describe the initial design of the dendronic image characterization environment (DICE) for the generation of dendronic signatures from complex multiband remote imagery. By comparing subdendrones within an image to dendronic signatures of target objects of interest, DICE can be used to match/retrieve target features from a library of composite images. The DICE framework can organize and support a number of alternative object recognition and comparison techniques, depending on the application domain. © 2001 John Wiley & Sons, Inc. Int J Imaging Syst Technol 11, 243,253, 2000 [source] Masked targets trigger event-related potentials indexing shifts of attention but not error detectionPSYCHOPHYSIOLOGY, Issue 3 2010Geoffrey F. Woodman Abstract To carry out tasks with the highest possible efficiency we have developed executive mechanisms that monitor task performance and optimize cognitive processing. It has been hypothesized that these executive mechanisms operate even without conscious awareness to maximize their sensitivity to task-relevant outcomes. To test this hypothesis the present study examined the error-related negativity (ERN), an electrophysiological index of the performance-monitoring neural circuitry, during masked visual search. The findings show that representations of target objects that are processed perceptually, but not to the level of awareness, fail to elicit an ERN despite the ability of these targets to elicit a shift of attention. These findings indicate that the performance-monitoring mechanism indexed by the ERN requires target information to be processed to the level of awareness for a mismatch between stimulus and response to be detected. [source] The Development of Memory for Location: What Role Do Spatial Prototypes Play?CHILD DEVELOPMENT, Issue 2 2001Jodie M. Plumert Two experiments investigated the role of spatial prototypes in estimates of location. In Experiment 1 (N= 144), children and adults learned the locations of 20 objects in an open, square box designed to look like a model house. In two conditions, opaque lines or walls divided the house into four regions, and in the other condition, no boundaries were present. Following learning, the dots marking the locations were removed, and participants attempted to replace the objects. Children and adults overestimated distances between target locations in different regions. Contrary to Huttenlocher, Hedges, and Duncan's hierarchical theory of spatial memory, none of the groups displaced the objects toward the region centers. In Experiment 2 (N == 96), boundaries were removed during testing to determine whether children and adults were more likely to displace objects toward region centers when uncertainty about location increased. Again, all age groups overestimated distances between target objects in different regions. In addition, adults and 11-year-olds in the most salient boundary condition displaced objects toward the region centers. Discussion focuses on the implications of these results for understanding how children and adults estimate location. [source] | ||||||||||