Tianren Liu

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OBJECTIVE To create an end-to-end system to identify temporal relation in discharge summaries for the 2012 i2b2 challenge. The challenge includes event extraction, timex extraction, and temporal relation identification. DESIGN An end-to-end temporal relation system was developed. It includes three subsystems: an event extraction system (conditional random(More)
OBJECTIVE In this paper, we focus on three aspects: (1) to annotate a set of standard corpus in Chinese discharge summaries; (2) to perform word segmentation and named entity recognition in the above corpus; (3) to build a joint model that performs word segmentation and named entity recognition. DESIGN Two independent systems of word segmentation and(More)
The possibility of basing the security of cryptographic objects on the (minimal) assumption that NP ⊈ BPP is at the very heart of complexity-theoretic cryptography. Most known results along these lines are negative, showing that assuming widely believed complexity-theoretic conjectures, there are no reductions from an NP-hard problem to the task of breaking(More)
1 Overview • Worst-case to average-case reduction Worst-case problems are typically harder than average-case problems. While if there is worst-case to average-case reduction, you are able to solve the problem in worst-case if you can solve a problem in average case.
  • Xijia Zheng, B Eng, Vincent W S Chan, Joan, Irwin Jacobs, Leslie A Kolodziejski +15 others
  • 2015
Optical Flow switching (OFS) is a key enabler of future scalable all-optical networks for the large traffic flows. In this thesis, we provide design concepts of efficient physical topology and routing architectures for an all-optical Metropolitan Area Network (MAN) that supports OFS. We use all-to-one stochastic flows to model inter-MAN traffic demands and(More)
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