Liang Yu

Dr. Liang Yu

State Key Laboratory of Mechanical System and Vibration, Shanghai Jiao Tong University, Shanghai 200240, China
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Research Focus & Metrics

Academic Career Length

22Years (2005-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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10 January 2008 in Transactions of the American Mathematical Society
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Journal Article
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JMJoseph Miller
Joseph Miller
LYLiang Yu
Liang Yu
One approach to understanding the fine structure of initial segment complexity was introduced by Downey, Hirschfeldt and LaForte. They define X ≤ K Y X\leq _K Y to mean that ( ∀ n ) K ( X ↾ n ) ≤ K ( Y ↾ n ) + O ( 1 ) (\forall n)\; K(X\upharpoonright n)\leq K(Y\upharpoonright n)+O(1) . The equivalence classes under this relation are the K K -degrees . We prove that if X ⊕ Y X\oplus Y is 1 1 -random, then X X and Y Y have no upper bound in the K K -degrees (hence, no join). We also prove that n n -randomness is closed upward in the K K -degrees. Our main tool is another structure intended to measure the degree of randomness of real numbers: the vL \textit {vL} -degrees. Unlike the K K -degrees, many basic properties of the vL \textit {vL} -degrees are easy to prove. We show that X ≤ K Y X\leq _K Y implies X ≤ vL Y X\leq _{\textit {vL}} Y , so some results can be transferred. The reverse implication is proved to fail. The same analysis is also done for ≤ C \leq _C , the analogue of ≤ K \leq _K for plain Kolmogorov complexity. Two other interesting results are included. First, we prove that for any Z ∈ 2 ω Z\in 2^\omega , a 1 1 -random real computable from a 1 1 - Z Z -random real is automatically 1 1 - Z Z -random. Second, we give a plain Kolmogorov complexity characterization of 1 1 -randomness. This characterization is related to our proof that X ≤ C Y X\leq _C Y implies X ≤ vL Y X\leq _{\textit {vL}} Y .

1 June 2016 in Journal of Sound and Vibration
Verified
Journal Article
Closed access
LYLiang Yu
Liang Yu
JAJerome Antoni
Jerome Antoni
QLQuentin Leclere
Quentin Leclere

17 May 2023 in Mechanical Systems and Signal Processing
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Journal Article
Closed access
RWRan Wang
Ran Wang
FYFucheng Yan
Fucheng Yan
LYLiang Yu
Liang Yu
CSChangqing Shen
Changqing Shen
XHXiong Hu
Xiong Hu
JCJin Chen
Jin Chen

1 November 2017 in Journal of Sound and Vibration
Verified
Journal Article
Closed access
LYLiang Yu
Liang Yu
JAJerome Antoni
Jerome Antoni
QLQuentin Leclere
Quentin Leclere
WJWeikang Jiang
Weikang Jiang

1 August 2015 in Journal of Sound and Vibration
Verified
Journal Article
Closed access
JAJerome Antoni
Jerome Antoni
LYLiang Yu
Liang Yu
QLQuentin Leclère
Quentin Leclère

1 September 2022 in ISA Transactions
Verified
Journal Article
Closed access
RWRan Wang
Ran Wang
HFHaitao Fang
Haitao Fang
LYLongjing Yu
Longjing Yu
LYLiang Yu
Liang Yu
JCJin Chen
Jin Chen