A common computation in visual cortex is the divisive normalization of responses by a pooled signal of the activity of cells within its neighborhood. From a geometrical point of view, normalization constraints the population response to high-contrast stimuli to lie on the surface of a high-dimensional sphere. Here we study the implications this constraint imposes on the representation of a circ...

We investigated the precision of orientation representations with two tasks, change detection and recall. Previously change detection has been measured only with relatively large orientation changes compared to psychophysical thresholds. In the first experiment, we measured the observers' ability (d') to detect small changes in orientation (5-30°) with 1-4 Gabor items. With one item even a 10° ...

Though a growing number of people are studying languages online, what motivates online language learners is not yet well understood. Drawing on data from an international survey conducted among users of a major online site, this study explored the motivational orientation of learners and its relationship to individual background. The results suggest instrumental and integrative orientation for ...

This study investigates the contributions of position versus orientation information in shape perception by putting the two in conflict. Sampling the orientation of, e.g., a rounded pentagon and positioning the samples on a circle creates a stimulus in which element positions are consistent with a circle but element orientations with a pentagon. Whether orientation or position dominates the per...

Given a bipartite graph, let us pick an acyclic orientation of its edges. Then, if we consider the partially ordered set (poset) induced by this orientation, the number of linear extensions of such a poset is maximal whenever the orientation is bipartite, or such that no directed path of length two exists. We define a sequence of automorphisms that injectively but nonbijectively map the set of ...

Although object orientation (OO) is not intrinsically difficult, it can be hard to understand and teach unless it is viewed and presented within a coherent framework. This paper presents a logical and coherent framework for understanding and teaching object orientation. Central to the framework is the separation of the concepts generally associated with object orientation into those relating to...

increasing non-oil exporting is among the most important concerns for iran. software industry is among the knowledge based and profitable ones. identification of factors affecting export performance of software developers can improve planning that in turn results in increasing software export. in this research a model consisting of seven important variables in software industries including: com...

the aim of this study was to investigate the effect of positive normative feedback on acquisition and retention of throwing skill. the method was quasi-experimental and the population consisted of the 5th grade elementary female students. 60 students were randomly selected from the population and were randomly assigned to four different groups: normative task-orientation, non-normative task-ori...