20 research outputs found
Principles and methods for face recognition and face modelling
This chapter focuses on the principles behind methods currently used for face recognition, which have a wide variety of uses from biometrics, surveillance and forensics. After a brief description of how faces can be detected in images, we describe 2D feature extraction methods that operate on all the image pixels in the face detected region: Eigenfaces and Fisherfaces first proposed in the early 1990s. Although Eigenfaces can be made to work reasonably well for faces captured in controlled conditions, such as frontal faces under the same illumination, recognition rates are poor. We discuss how greater accuracy can be achieved by extracting features from the boundaries of the faces by using Active Shape Models and, the skin textures, using Active Appearance Models, originally proposed by Cootes and Talyor. The remainder of the chapter on face recognition is dedicated such shape models, their implementation and use and their extension to 3D. We show that if multiple cameras are used the the 3D geometry of the captured faces can be recovered without the use of range scanning or structured light. 3D face models make recognition systems better at dealiing with pose and lighting variatio
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Developing reflection on values as a foundation for a business career
Students can learn to analyse questions of ethics from the philosophical perspectives of duties, consequences and virtues. This includes the development of empathy and moral courage. Our brains respond to the experiences of others using 'empathy neurons'; we are 'hard-wired' for empathy. Developing moral courage can be linked to the development of empathy, drawing on 'ethics of care' theories. Graduates who express empathy for their colleagues and care for themselves are better equipped to act ethically. We show how learning experiences can enable students to develop problem-solving responses as an alternative to 'fight or flight' reactions to ethical problems. We can help students to develop expertise in ethics by providing them with more opportunities to engage rationally and empathically with ethical problems, through active learning experiences followed by critical reflective processes. Discussing moral exemplars in active learning helps to avoid a cynical view that unethical behaviour is normal. Critical reflection encourages students to make more use of their rational and empathic capacities. The theory of cognitive dissonance helps students to become aware of how we tend to seek information that confirms our decisions while avoiding information that would alert us to ethical hazards