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Research has shown that people recognize personality, gender, inner states and many other items of information by simply observing human motion. Therefore the expressive human motion seems to be a valuable non-verbal communication channel. On the quest for more believable characters in virtual three dimensional simulations a great amount of visual realism has been achieved during the last decades. However, while interacting with synthetic characters in real-time simulations, often human users still sense an unnatural stiffness. This disturbance in believability is generally caused by a lack of human behavior simulation. Expressive motions, which convey personality and emotional states can be of great help to create more plausible and life-like characters. This thesis explores the feasibility of an automatic generation of emotionally expressive animations from given neutral character motions. Such research is required since common animation methods, such as manual modeling or motion capturing techniques, are too costly to create all possible variations of motions needed for interactive character behavior. To investigate how emotions influence human motion relevant literature from various research fields has been viewed and certain motion rules and features have been extracted. These movement domains were validated in a motion analysis and implemented in a system in an exemplary manner capable of automating the expression of angry, sad and happy states in a virtual character through its body language. Finally, the results were evaluated in user test.
We introduce linear expressions for unrestricted dags (directed acyclic graphs) and finite deterministic and nondeterministic automata operating on them. Those dag automata are a conservative extension of the Tu,u-automata of Courcelle on unranked, unordered trees and forests. Several examples of dag languages acceptable and not acceptable by dag automata and some closure properties are given.
Computed tomography (CT) and magnetic resonance imaging (MRI) in the medical area deliver huge amounts of data, which doctors have to handle in a short time. These data can be visualised efficiently with direct volume rendering. Consequently most direct volume rendering applications on the market are specialised on medical tasks or integrated in medical visualisa- tion environments. Highly evolved applications for tasks like diagnosis or surgery simulation are available in this area. In the last years, however, another area is making increasing use of com- puted tomography. Companies like phoenix |x-ray, founded in 1999 pro- duce CT-scanners especially dedicated to industrial applications like non destructive material testing (NDT). Of course an application like NDT has different demands on the visualisation than a typical medical application. For example a typical task for non destructive testing would be to high- light air inclusions (pores) in a casting. These inclusions usually cover a very small area and are very hard to classify only based on their density value as this would also highlight the air around the casting. This thesis presents multiple approaches to improve the rendering of in- dustrial CT data, most of them based on higher dimensional transfer func- tions. Therefore the existing volume renderer application of VRVis was extended with a user interface to create such transfer functions and exist- ing render modes were adapted to profit from the new transfer functions. These approaches are especially suited to improve the visualisation of sur- faces and material boundaries as well as pores. The resulting renderings make it very easy to identify these features while preserving interactive framerates.