| Adaptive Information Filtering |
25 Feb 2011 |
6 pages |
| Authors:
Yi Zhang; CALIFORNIA UNIV SANTA CRUZ
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 | This project studies personalized proactive information filtering agents that pushes relevant information to the user without requiring explicit user query. To do this, the agent adaptively learns a detailed user model while observing and interacting with the user. We use Bayesian statistical theory and machine learning techniques to tackle the following two major challenges. We studied two major problems: how to build an initial user profile with minimal user effort, ... |
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| Probes for Narcotic Receptor Mediated Phenomena. 39. Enantiomeric N-Substituted Benzofuro[2,3-c]pyridin-6-ols: Synthesis and Topological Relationship to Oxide-Bridged Phenylmorphans |
Jan 2009 |
11 pages |
| Authors:
Yi Zhang; Yong S Lee; Richard B Rothman; Christina M Dersch; Jeffrey R Deschamps; Arthur E Jacobson; Kenner C Rice; NATIONAL INSTITUTES OF HEALTH BETHESDA MD
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| Enantiomers of N-substituted benzofuro[2,3-c]pyridin-6-ols have been synthesized, and the subnanomolar affinity and potent agonist activity of the known racemic N-phenethyl substituted benzofuro[2,3-c]pyridin-6-ol can now be ascribed to the 4aS,9aR enantiomer. The energy-minimized structures suggest that the active enantiomer bears a greater three-dimensional resemblance to morphine than to an ostensibly structurally similar oxide-bridged phenylmorphan. Structural features of the conformers of N-substituted benzofuro[2,3-c]pyridin-6-ols were compared to provide the rationale for their binding ... |
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| The Bias Problem and Language Models in Adaptive Filtering |
2006 |
7 pages |
| Authors:
Yi Zhang; Jamie Callan; CARNEGIE-MELLON UNIV PITTSBURGH PA SCHOOL OF COMPUTER SCIENCE
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| We used the YFILTER filtering system for experiments on updating profiles and setting thresholds. We developed a new method of using language models for updating profiles that is more focused on picking informative/discriminative words for query. The new method was compared with the well-known Rocchio algorithm. Dissemination thresholds were set based on maximum likelihood estimation that models and compensates for the sampling bias inherent in adaptive filtering. Our experimental results ... |
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| Structure and Oscillations in Quiescent Filaments from Observations in He I Wavelength 10830 A |
Jan 1991 |
20 pages |
| Authors:
Yi Zhang; Oddbjorn Engvold; Stephen L Keil; PHILLIPS LAB HANSCOM AFB MA
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| Observations of two quiescent filaments show oscillatory variations in Doppler shift and central intensity of the He I Solar 10830 Angstroms line. The oscillatory periods range from about 5 to 15 min. with dominant periods of 5, 9, and 16 min. The possibility that the oscillations are Alfven waves is discussed. The Doppler signals of the filament form fibril-like structures. The fibrils are all inclined at an angle of about ... |
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