Academic Report
Title: 2019 Mathematics Academic Exchange Conference Dalian University of Technology-Xi'an Jiaotong University
Time: Apirl 20, 2019 (Saturday) AM 8:15
Location: A1101# room, Innovation Park Building
Title: Measuring the impact of air pollution on respiratory infectionrisk in China
Abstract: China is now experiencing major public health challenges caused by air pollution. There are many challenges to quantifying the dynamics of air pollution and evaluating its impact of on the risk of respiratory infection. This talk presented a novel methodology through integrating correlation analysis, relative risk evaluation and dynamic models with an air quality index (AQI)-related incidence and interventions. Our analysis illustrated the respiratory infection risk has increased progressively with increased AQI with a time lag of 0-3 days. Our combined data and modelling analysis estimated the basic reproduction number for the respiratory infection during the studying period to be 2.4076, higher than the basic reproduction number of the 2009 pandemic influenza in the same province. Our modelling-based simulations concluded that, in terms of respiratory infection risk reduction, the persistent control of emission in the China's blue-sky programme is much more effective than substantial social-economic interventions implemented only during the smog days. The prediction and evaluation suggested that a combination of statistical analysis with mathematical modelling with available surveillance and environmental data can provide substantial information about AQI dynamics and its impact on respiratory infection dynamics.Joint work with Sanyi Tang, Qinling Yan, Wei Shi and PhD students.
Title: The stability of full dimensional KAM tori for nonlinear Schrödinger equation
Abstract: In this talk, we will discuss the existence and long time stability the full dimensional invariant tori for 1D nonlinear Schrödinger equation with periodic boundary conditions.
Title: Shape design in the incompressible viscous fluids
Abstract: In this talk, I will briefly introduce the shape inverse design and shape optimal design in incompressible viscous fluids. The first part of the talk is concerned with the shape reconstruction of a bounded and smooth domain from the observed information in the Navier- Stokes flow. The continuous dependence of the solution on variations of the boundary is established, and the explicit representation of domain derivative of correspondin rse problem. In the second part, the shape optimization problem of a body immersed in the incompressible fluid governed by Navier-Stokes equations is considered. Then the structure of shape gradient for the cost functional is derived by the differentiability of a minimax formulation involving a Lagrange functional with the function space parametrization technique. Moreover, a gradient- type algorithm is employed to solve the shape optimization problem. The numerical examples demonstrate the feasibility and effectiveness of the proposed algorithm.
Title: On Piecewise Sparse Signal Recovery
Abstract: In some applications, there are signals with piecewise sparse structure to berecovered. It needs to be pointed out that the piecewise sparse vector is quite different from the block sparse vector, which are well studied. In this talk, we will introduce some new results and algorithms on piecewise sparse signal recovery.
Title: Research on Intelligent Wireless Communication
Abstract: In this talk, I will share the research experiences and results about intelligent wireless communication, which are based on the works done recently. Intelligent wireless communication is the future technique after 5G system, and it could make the wireless communication system more adaptive and intelligent by using machine learning methods. Meanwhile, this talk will show you how it works for preamble detection in IoT, signal detection for MIMO system, adaptive CSI estimation by noise modelling, etc.. it will also show great improvement can be achieved by machine learning in new are.
Title: Numerical model and experiment of boundary integral equation for ocean internal waves
Abstract: Internal waves are ubiquitous in the ocean, and the enormous energy they carry is a great threat to ocean platforms, submarines and other marine structures. By simplifying it into two-layer fluid, a fully non-linear numerical model of internal wave generation is established by using the boundary integral equation method, and the calculation method is improved. The internal wave characteristics generated by moving point vortices and hydrofoils are analyzed. The effects of internal wave and surface wave are considered. The physical model experiments of internal wave evolution through changing terrain and its flow field characteristics are carried out.
Title: Liouville correspondences between multi-component integrable hierarchies
Abstract: This is a joint result with Peter J. Olver, Changzheng Qu and Jing Kang. We study explicit correspondences between some multi-component integrable hierarchies. We show how the Liouville transformations between the isospectral problems of the multi-component systems relate the corresponding hierarchies, in both positive and negative directions, as well as their associated conservation laws. This extends previous results on the scalar hierarchies to the multi-component case.
Title: Recent results for the steady Navier-Stokes equations-a Liouville-type perspective
Abstract: In this talk, we will recall some developments about the steady Navier-Stokes equations, especially from a Liouville-type perspective. Also, we will talk about our recent results on this topic and some remaining questions.
