Xiaojun Yuan

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Query length in best-match information retrieval (IR) systems is well known to be positively related to effectiveness in the IR task, when measured in experimental, non-interactive environments. However, in operational, interactive IR systems, query length is quite typically very short, on the order of two to three words. We report on a study which tested(More)
[1] Evidence of El Niño-Southern Oscillation (ENSO) teleconnections in the southern high latitude climate has been identified, although the mechanisms that might lead to such far-reaching teleconnections remain unresolved. Here we propose one such mechanism-the regional mean meridional atmospheric circulation (the regional Ferrel Cell)-responsible for the(More)
[1] This study investigates the influence of high-latitude climate variability on the Antarctic sea ice distribution. The climate variability examined here includes distinct climate modes, such as the Southern Annular Mode (SAM), quasi-stationary wave-3 pattern, Pacific South American pattern (PSA) and Semi-Annual Oscillation (SAO). The results reveal that(More)
0169-023X/$ see front matter 2008 Elsevier B.V doi:10.1016/j.datak.2008.05.004 q CiteSpace is available at http://cluster.cis.drexel.e papers/2008/dke/figures. * Corresponding author. E-mail addresses: chaomei.chen@cis.drexel.edu ( The thematic and citation structures of Data and Knowledge Engineering (DKE) (1985–2007) are identified based on text analysis(More)
We describe results from an ongoing project that considers question types and document features and their relationship to retrieval techniques. We examine eight document features from the top 25 documents retrieved from 74 questions and find that lists and FAQs occur in more documents judged relevant to task-oriented questions than those judged relevant to(More)
Air-sea-ice interaction processes in the Southern Ocean are investigated utilizing space-observed surface winds, sea ice concentration, and sea surface temperature (SST) from September through December, 1996. The sea ice edge (SIE) shows three ice-extent maxima around the Antarctic during September and October when sea ice coverage is maximum. They are(More)