Log-Euclidean Bag of Words for Human Action Recognition

Representing videos by densely extracted local space-time features has recently become a popular approach for analysing actions. In this paper, we tackle the problem of categorising human actions by devising Bag of Words (BoW) models based on covariance matrices of spatio-temporal features, with the features formed from histograms of optical flow. Since covariance matrices form a special type of Riemannian manifold, the space of Symmetric Positive Definite (SPD) matrices, non-Euclidean geometry should be taken into account while discriminating between covariance matrices. To this end, we propose to embed SPD manifolds to Euclidean spaces via a diffeomorphism and extend the BoW approach to its Riemannian version. The proposed BoW approach takes into account the manifold geometry of SPD matrices during the generation of the codebook and histograms. Experiments on challenging human action datasets show that the proposed method obtains notable improvements in discrimination accuracy, in comparison to several state-of-the-art methods

Virtually There: A Phenomenological Study of Secondary Students and Their Engagement with Virtual Reality Field Trips

The study seeks to inform solution to the lack of student exposure to frequent, culturally enriching field trips in school. To address the concern of limited learning through school field trips, this phenomenological study seeks to explore the lived experiences of virtual reality field trips for secondary students. The study seeks to examine how students respond emotionally, physically, and cognitively to the use of virtual reality within the classroom. Data analysis consists of observing, interviewing, and assessing students as they engage in and complete a virtual reality field trip. The three research domains are transcribed and analyzed to better understand how students respond in a virtual field trip. The results will lead to further studies on the use of virtual reality field trips as a teaching strategy to improve student learning

Cultivating Lifelong Donors: Stewardship and the Fundraising Pyramid

This handbook helps nonprofits build long-term giving programs that span the entire supporter lifecycle, from engagement through the end of life. It highlights strategies for engaging new supporters online, investigates the characteristics of loyal donors, examines the importance of developing personal relationships with transitional giving prospects, and discusses donor cultivation

Enhanced Behavioral Recovery from Sensorimotor Cortex Lesions After Pyramidotomy in Adult Rats

Unilateral transection of the bulbar pyramid, performed before the ablation of the ipsilateral sensorimotor cortex, has been shown to facilitate the recovery of operantly conditioned reflexes and compensatory processes in rats. Such enhanced behaviorai recovery was absent when only the sensorimotor cortex was ablated. This phenomenon is explained by the switching of motor activity under the control of the cortico-rubrospinal system. Switching of the descending influences is accomplished through the following loop: cortico-rubrai projectionred nucleus-inferior olive-cerebellum-thalamuscerebral cortex. This suggests that a preliminary lesion of the peripheral part of the system, represented by a descending spinal projection, facilitates the recovery processes to develop during the subsequent destruction of its central part