All posts by Dr. Ellen Dekkers

About Dr. Ellen Dekkers

RWTH-Aachen University - Aachen - Germany

Cultural differences in academic motivation goals: a meta-analysis across 13 societies

A meta-analysis of academic motivation focused on the relations between students’ achievement goal orientations and societal values and human development indicators. The authors analyzed relevant studies using either Andrew Elliot and Marcy Church’s (1997) or Michael Middleton and Carol Midgley’s (1997) achievement goal instruments separating mastery, performance approach, and performance avoidance goals, with 36.985 students from 13 societies. Ecological correlation and regression analyses showed that mastery goals are higher in egalitarian societies, whereas performance approach goals are higher in more embedded contexts and in less developed societies. Performance avoidance goals did not strongly relate to societal-level variables. The findings show that achievement goals are rooted within dominant societal values.

Article originally published in ‘The Journal of Educational Research’ V. 102 (2008), November/December, //

Reprinted with permission

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Character animation from 2D pictures and 3D motion data

This article presents a new method to animate photos of 2D characters using 3D motion capture data. Given a single image of a person or essentially human-like subject, our method transfers the motion of a 3D skeleton onto the subject’s 2D shape in image space, generating the impression of a realistic movement. We present robust solutions to reconstruct a projective camera model and a 3D model pose which matches best to the given 2D image. Depending on the reconstructed view, a 2D shape template is selected, which enables the proper handling of occlusions. After fitting the template to the character in the input image, it is deformed as-rigid-as-possible by taking the projected 3D motion data into account. Unlike previous work, our method thereby correctly handles projective shape distortion. It works for images from arbitrary views and requires only a small amount of user interaction. We present animations of a diverse set of human (and non-human) characters with different types of motions, such as walking, jumping, or dancing.

Article originally published as: Hornung, A. et al, Character Animation from 2D Pictures and 3D Motion Data, ‘ACM Transactions on Graphics (TOG)’, V. 26 (2007), n.1, ¬©2007 Association for Computing Machinery, Inc.¬† //

Reprinted with permission.