In the directed Steiner tree (DST) problem, we are given an $n$-vertex edge-weighted graph, a root $r$, and collection of $k$ terminal nodes. Our goal is to find minimum-cost subgraph that contains path from $r$ every terminal. We present $O(\log^2 k/\log\log{k})$-approximation algorithm for DST runs in quasi-polynomial time, i.e., time $n^{{poly}\log (k)}$. By assuming projection game conjectu...

This paper investigates the applicability of Informedia shot-based interface features for video retrieval in the hands of novice users, noted in past work as being too reliant on text search. The Informedia interface was redesigned to better promote the availability of additional video access mechanisms, and tested with TRECVID 2005 interactive search tasks. A transaction log analysis from 24 n...

Our goal is to develop a web server log analysis tool that produces a web site profile and its system resource usage in a way useful to service providers. Understanding the nature of traffic to the web site is crucial in properly designing site support infrastructure, especially for large, busy sites. The main questions we address in this paper are the new access patterns of today’s WWW, how to...