Exponential growth of the semiconductor industry, historically driven by transistor scaling, is now facing fundamental challenges. In this talk, I will discuss an emerging class of devices that, by merging electronic with ionics, offer the potential to control the materials’ electronic properties in-situ and have led to promising memory and circuit concepts. These devices exhibit history-dependent, resistive switching behavior and are termed memristors (memory + resistor) or resistive memory (RRAM) devices. I will discuss our efforts on the development and optimization of memristor devices and integrated systems, including techniques of controlling the dynamic ionic migration processes and associated modeling efforts. Functional high-density crossbar arrays have been integrated directly on top of CMOS circuits using a back-end-of-line (BEOL) process, enabling hybrid non-volatile memory and reconfigurable circuit applications.

Dirichlet problems for the second order elliptic partial differential equations have been studied for many years and obtained many existence results in 1980s. But there has been little research on Neumann problem in the past thirty years. In this talk, we will especially introduce Neumann problem for mean curvature equations and give the existence Theorem of classical solutions of mean curvature equations. The key point is to prove the boundary gradient estimate. (This is a joint work with Prof. Xinan Ma.

We discuss some results and problems concerning the construction of quantum channels with desired properties. No quantum mechanics background is required. Basic linear algebra knowledge is assumed.

Cone spherical, flat and hyperbolic metrics are conformal metrics with constant curvature +1; 0 and -1, respectively, and with finitely many conical singularities on compact Riemann surfaces. The Gauss-Bonnet formula gives a natural necessary condition for the existence of such three kinds of metrics with prescribed conical singularities on compact Riemann surfaces. The condition is also sufficient for both flat and hyperbolic metrics. However, it is not the case for cone spherical metrics, whose existence has been an open problem over twenty years. In this talk, we shall report the respectable audience the recent progresses on cone spherical metrics via Complex Analysis and Algebraic Geometry, which consist of several joint research works with Qing Chen, Lingguang Li, Jijian Song, Yingyi Wu and some of my (former) students.

The talk consists of four sections: 1. The algebras Wd,f Wd, Kd, gld 2. Shen’s monomorphism 3. Modules over Wn 4. The results This talk is based on: [X. Guo, G. Liu, R. Lu, K. Zhao, Simple Witt modules that are finitely generated over the Cartan subalgebra, arXiv:1705.03393].

We introduce a notion of a Nijenhuis operator on a pre-Lie algebra from the deformation theory. Then we explain the relationships between Nijenhuis operators and O-operators and Rota-Baxter operators. In particular, one can use Nijenhuis operators on a pre-Lie algebra to construct compatible O-operators as well as compatible L-dendriform algebras. The roles of Nijenhuis operators on pre-Lie algebras in some geometric structures are also interpreted.

题目：Minimal Integrity Bases and Irreducible Function Bases of Isotropic Invariants of Two Third Order Tensors报告人：祁力群 教授 （香港理工大学 ）地点：宁静楼110室时间：2017年12月14日(周四)下午16:00欢迎大家前往听讲

Measurement errors and outliers often arise in longitudinal data, ignoring the effects of measurement errors and outliers will lead to seriously biased estimators. Therefore, it is important to take them into account in longitudinal data analysis. In this paper, we develop a robust estimating equation method for analysis of longitudinal data with covariate measurement errors and outliers. Specifically, we eliminate the effects of measurement errors by making use of the independence of replicate measurement errors and correct the bias induced by outliers through centralizing the matrix of error-prone covariates in the estimating equation.