http://hdl.handle.net/10397/3371 Search the Channel search http://repository.lib.polyu.edu.hk/jspui/simple-search http://hdl.handle.net/10397/3876 Title: Toward realistic virtual surgical simulation : using heuristically parameterized anisotropic mass-spring model to simulate tissue mechanical responses<br/><br/>Authors: Choi, Kup-Sze<br/><br/>Abstract: Mass-spring model is a popular method to simulate soft tissues in virtual surgery applications. However, the setting of appropriate model parameters to reproduce the real mechanical responses of the tissues, which is anisotropic in general, remains an issue. This paper presents a hybrid heuristic approach to identify the parameters by incorporating simulated annealing into genetic algorithms. The optimization process is performed with reference to the benchmarks obtained by applying continuum mechanics and the finiteelement method. Experiments are performed to evaluate the feasibility of the approach.<br/><br/>Description: DOI: 10.1109/ICETC.2010.5529212 http://hdl.handle.net/10397/3709 Title: Integrating PhysX and OpenHaptics : efficient force feedback generation using physics engine and haptic devices<br/><br/>Authors: Chan, Leon Sze-Ho; Choi, Kup-Sze<br/><br/>Abstract: Haptic feedback plays an important role to further enhance the level of realism of virtual environments. However, rendering of realistic haptic feedback depends on its coupling to the underlying physics engine that governs the behavior of virtual objects. This paper presents methods to streamline the generation of haptic feedback with physics engine based on Sensable's OpenHaptics and nVidia's PhysX. Minimal development effort is required to couple these two components. To render the forces due to the interactions between virtual objects, the Error-based method and the Contact Plane Collision Response method are proposed to utilize virtual material stiffness and object collision geometry provided by PhysX. The latter method yields more jitter-free output by restricting the haptic interface on one side of the contact plane. While PhysX does not release force information from the engine, an intuitive technique is proposed to simulate a static or dynamic pulling force by introducing a spring between the haptic interface and the object being pulled. The use of these methods provides the desired force feedback without significant changes to the developer's codebase.<br/><br/>Description: DOI: 10.1109/JCPC.2009.5420068 http://hdl.handle.net/10397/3627 Title: Learning takes place : a need to examine our nursing curriculum<br/><br/>Authors: Chan, Engle Angela