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Yiyun Tracey Yang

Renmin University of China
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Areas of Interest
20th Century Philosophy
  •  24
    A nonlow2 R. E. Degree with the Extension of Embeddings Properties of a low2 Degree
    with R. A. Shore
    Mathematical Logic Quarterly 48 (1): 131-146. 2002.
    We construct a nonlow2 r.e. degree d such that every positive extension of embeddings property that holds below every low2 degree holds below d. Indeed, we can also guarantee the converse so that there is a low r.e. degree c such that that the extension of embeddings properties true below c are exactly the ones true belowd.Moreover, we can also guarantee that no b ≤ d is the base of a nonsplitting pair
    Areas of Mathematics
  •  10
    Ct Chong
    with C. T. Cl-Iong
    In Edward R. Griffor (ed.), Handbook of Computability Theory, Elsevier. pp. 140--298. 1999.
    Asian Philosophy
  •  46
    The minimal e-degree problem in fragments of Peano arithmetic
    with M. M. Arslanov, C. T. Chong, and S. B. Cooper
    Annals of Pure and Applied Logic 131 (1-3): 159-175. 2005.
    We study the minimal enumeration degree problem in models of fragments of Peano arithmetic () and prove the following results: in any model M of Σ2 induction, there is a minimal enumeration degree if and only if M is a nonstandard model. Furthermore, any cut in such a model has minimal e-degree. By contrast, this phenomenon fails in the absence of Σ2 induction. In fact, whether every Σ2 cut has minimal e-degree is independent of the Σ2 bounding principle
    Logic and Philosophy of LogicModel Theory
  •  1
    Evidence for breathing modes in direct current, pulsed, and high power impulse magnetron sputtering plasmas
    with X. Zhou, J. X. Liu, and A. Anders
    © 2016 AIP Publishing LLC.We present evidence for breathing modes in magnetron sputtering plasmas: periodic axial variations of plasma parameters with characteristic frequencies between 10 and 100 kHz. A set of azimuthally distributed probes shows synchronous oscillations of the floating potential. They appear most clearly when considering the intermediate current regime in which the direction of azimuthal spoke motion changes. Breathing oscillations were found to be superimposed on azimuthal sp…Read more