research

My research interests include problems relating to dynamic multi-relational social network analysis – in particular, community dynamics, social information summarization and representation. My current research, Community Discovery in Dynamic, Rich Media Social Networks, focuses on extracting human communities that collaborate around certain topics or media sharing activities.

I have also conducted work on spam blog ("splog") detection based on link connectivity and temporal properties of blogs. There I combined traditional content based features with temporal and link signatures with excellent results.

Prior to my Ph.D. study, I was interested in the area of computer graphics, with a particular concentration on non-photorealistic rendering. In my master thesis, I proposed a rendering framework that renders three-dimensional models in a synthetic Chinese painting style.

Social Network Analysis - Community Discovery in Dynamic, Rich Media Social Networks

With the rapid proliferation of different types of social media, such as instant messaging (e.g., AIM, MSN, Skype), media sharing sites (e.g., Flickr, YouTube), blogs (e.g., Blogger, WordPress, LiveJournal), wikis (e.g., Wikipedia, PBWiki), microblogs (e.g., Twitter, Jaiku), social networks (e.g., MySpace, Facebook), to mention a few, users routinely produce (e.g. blogs) and consume media (e.g. YouTube) as well as interact with each other through a wide array of functionality provided by various social media. These social media depend largely on implicit communities of online users to deliver value. Identifying and analyzing the dynamics of such latent communities can lead to improved functionality of the social media as well as provide insight into the design of future online collaborative services. The problem is particularly important in the enterprise domain where extracting emergent community structure on enterprise social media, can help in forming new collaborative teams, in expertise discovery, and guide long term enterprise reorganization.

My work studies three aspects of community analysis in dynamic, rich media social networks: (1) Community evolution – How do we identify communities in large scale, dynamic social networks, and analyze their structures and evolutions? (2) Community summarization – How do we summarize community activities, in order to trace community interests or retrieve community generated content? (3) Multi-relational communities – How do we discover communities when the social networks exist in a highly connected web of contexts (e.g., social groups, geographic locations, time, etc.)?

Community evolution

Community summarization

Multi-relational communities

Social media and human interactions

Adversarial Information Retrieval on the Web – Splog Detection

Our work deals with detecting spam blogs (splogs), a major problem in the blogosphere. Splogs are undesirable blogs meant to attract search engine traffic, used solely for promoting affiliate sites.

Computer Graphics – Non-photorealistic Rendering

The research considers non-photorealistic rendering (NPR) technique that deals with problem of reducing the visual complexity while maintaining the aesthetic value of synthesized images. NPR stems from a key insight: artistic works are not necessarily photorealistic, whereas the observer can still comprehend the information delivered by the artists, based on the artistic context of the work. Theses papers present a framework for automatically drawing three-dimensional trees (one of the essential painting subjects in Chinese landscape painting) in Chinese ink painting style. We address the problem by leveraging computer rendering techniques with knowledge about Chinese painting. Our approach includes image-based outline rendering and texture generation according to the information captured from the three-dimensional objects. We introduce novel reference maps to analyze the information for creating the brush strokes, textures, and inking parameters of washing tone. Stylized textures are created by procedurally defining the texture patterns. The analytical painting framework can be extended to draw other subjects in Chinese ink painting style. We demonstrate the results of our method with excellent 2D/3D rendering results. (details and papers)