A Fast Order-Based Approach for Core Maintenance

Graphs have been widely used in many applications such as social networks, collaboration networks, and biological networks. One important graph analytics is to explore cohesive subgraphs in a large graph. Among several cohesive subgraphs studied, k-core is one that can be computed in linear time for a static graph. Since graphs are evolving in real applications, in this paper, we study core maintenance which is to reduce the computational cost to compute k-cores for a graph when graphs are updated from time to time dynamically. We identify drawbacks of the existing efficient algorithm, which needs a large search space to find the vertices that need to be updated, and has high overhead to maintain the index built, when a graph is updated. We propose a new order-based approach to maintain an order, called k-order, among vertices, while a graph is updated. Our new algorithm can significantly outperform the state-of-the-art algorithm up to 3 orders of magnitude for the 11 large real graphs tested. We report our findings in this paper

Virtual tourism – Digital scanning, Augmented Reality and Virtual Reality as a Holistic Approach to Chinese Historic Building Preservation

There are many historical buildings spread around the rural areas of China and very few of them have been documented through digital media. In the face of massive Chinese urbanization, many of these cultural relics are facing the risk of damage, collapse, and even disappearance. The undocumented disappearance of these monuments would be a great loss for Chinese traditional culture and therefore this thesis proposes to solve this preservation problem using a combination of digital media platforms including 3D digital reconstruction, virtual reality, and augmented reality to digitally document and present these monuments. This thesis introduces these three technologies individually by presenting case studies for each to illustrate in greater depth the value each technology brings into the realm of heritage conservation. In the final section of this thesis, a mixed reality educational mobile application is presented as a test of this integrated technology solution to explore the potential of implementing this solution on a massive scale