On deformations of quasi-Miura transformations and the Dubrovin-Zhang bracket

In our recent paper we proved the polynomiality of a Poisson bracket for a class of infinite-dimensional Hamiltonian systems of PDE's associated to semi-simple Frobenius structures. In the conformal (homogeneous) case, these systems are exactly the hierarchies of Dubrovin-Zhang, and the bracket is the first Poisson structure of their hierarchy. Our approach was based on a very involved computation of a deformation formula for the bracket with respect to the Givental-Y.-P. Lee Lie algebra action. In this paper, we discuss the structure of that deformation formula. In particular, we reprove it using a deformation formula for weak quasi-Miura transformation that relates our hierarchy of PDE's with its dispersionless limit.Comment: 21 page

Yingjin Zhang. The city in modern Chinese literature and film : configurations of space, time, and gender

This article reviews the book The City in Modern Chinese Literature and Film: Configurations of Space, Time, and Gender written by Yingjin Zhang

AutoFlow: An automatic debugging tool for AspectJ software

Aspect-oriented programming (AOP) is gaining popu-larity with the wider adoption of languages such as As-pectJ. During AspectJ software evolution, when regression tests fail, it may be tedious for programmers to find out the failure-inducing changes by manually inspecting all code editing. To eliminate the expensive effort spent on debug-ging, we developed AutoFlow, an automatic debugging tool for AspectJ software. AutoFlow integrates the potential of delta debugging algorithm with the benefit of change im-pact analysis to narrow down the search for faulty changes. It first uses change impact analysis to identify a subset of re-sponsible changes for a failed test, then ranks these changes according to our proposed heuristic (indicating the likeli-hood that they may have contributed to the failure), and finally employs an improved delta debugging algorithm to determine a minimal set of faulty changes. The main fea-ture of AutoFlow is that it can automatically reduce a large portion of irrelevant changes in an early phase, and then locate faulty changes effectively.