  In any search-based digital library (DL) systems dealing with a non-trivial
number of documents, users are often required to go through a long list of
short document descriptions in order to identify what they are looking for. To
tackle the problem, a variety of document organization algorithms and/or
visualization techniques have been used to guide users in selecting relevant
documents. Since these techniques require heavy computations, however, we
developed a presentation server designed to serve as an intermediary between
retrieval servers and clients equipped with a visualization interface. In
addition, we designed our own visual interface by which users can view a set of
documents from different perspectives through layers of document maps. We
finally ran experiments to show that the visual interface, in conjunction with
the presentation server, indeed helps users in selecting relevant documents
from the retrieval results.
