交大讲座概览丨2019.09.16-09.22

人文社科类

题目：  Its a Small World: The Importance of Social Connections with Auditors to Mutual Fund Managers Portfolio Decisions

学院：安泰经济与管理学院

题目：  Workshop on Social Network Analysis

学院：安泰经济与管理学院

题目：  Capital Income Taxation and Self-fulfilling Aggregate Instability

学院：安泰经济与管理学院

理工类

题目: Are urban greenspaces safe for nature and humans alike?

学院：农业与生物学院

题目: Urban trees: what do we know about the services they provide?

学院：农业与生物学院

题目: 以学习为中心的教学设计

学院：数学科学学院

题目: Symmetries of Ordinary Differential Equations (II)

学院：数学科学学院

题目: Stability of smooth soliton for the Degasperis-Procesi equation

学院：数学科学学院

题目: 半导体量子结构中的自旋轨道耦合和量子相

学院：物理与天文学院

题目: A few properties of global solutions of the heat equation on Euclidean space and some manifolds

学院：数学科学学院

题目: 【文俊讲坛】听音辨群

学院：数学科学学院

题目: Liouville properties of the Navier-Stokes

学院：数学科学学院

题目: Does the ratio of Laplace transforms of powers of a function identify the function?

学院：数学科学学院

题目:千禧年七大数学难题之一：Navier-Stokes 方程的历史渊源

学院：数学科学学院

It’s a Small World: The Importance of Social Connections with Auditors to Mutual Fund Managers’ Portfolio Decisions

2019年9月16日 14:00—16:00

上海交通大学 徐汇校区包图A305

Jun Huang，Professor in accounting, Shanghai University of Finance and Economics

上海交通大学安泰经济与管理学院

We examine the impact of social connections between mutual fund managers and auditors of public firms on mutual fund stockholdings. We find that mutual funds whose managers are socially connected with firm auditors hold more shares of these firms. In cross-sectional tests, we find that the effect of social connections on mutual fund stockholdings is more pronounced when the social connections are stronger, for small audit firms, and for public firms with greater business opacity, stock price synchronicity, and systematic risk. We further document that mutual funds with socially connected auditors engage more in informed trading and generates superior portfolio returns. In compensation, connected auditors benefit from more audit business and higher audit and non-audit fees from public firms. Our findings suggest information transfer from auditors to mutual fund managers through their social connections, which helps mutual fund portfolio decisions.

Workshop on Social Network Analysis

2019年9月18日 14:30-16:30

上海交通大学 徐汇校区 A305室

Israr Qureshi 教授　 Australian National University 澳大利亚国立大学

上海交通大学安泰经济与管理学院

Social Network Analysis is increasingly being used across various disciplines such as organizational studies, management, business, sociology, political science, communications, etc. Quantitative empirical studies that analyze social, management, and business phenomena, formulate hypotheses, and test them through social network analysis are increasing in social sciences, including management and organization research. In this workshop, we will learn how to apply social network analysis to test various theories. This workshop is geared towards providing foundations in social network methodologies that covers data collection, research ethics, and data analysis. We will use the UCINET software.

Capital Income Taxation and Self-fulfilling Aggregate Instability

2019年9月18日 14:30-16:30

上海交通大学 徐汇校区 A305室

Xue Jianpo, Professor, WISE, Xiamen University

上海交通大学安泰经济与管理学院

We propose a theory of self-fulfilling instability induced by capital income taxation. In a neoclassical economy with constant returns where the government adjusts capital tax rates to ensure fiscal sustainability, interaction between capital tax and utilization rates generates fiscal increasing returns and factor share redistribution to induce multiple equilibria. Self-fulfilling instability can occur in real-world economies, unless their depreciation allowances are sufficiently higher or tax rates lower than the current levels. Besides providing a novel and policy-based microfoundation for aggregate increasing returns, our results add a short-run motivation to the long-run approach to capital taxation calling for lower tax rates.

Are urban greenspaces safe for nature and humans alike?

2019-09-16　14:30 — 16:00

农业与生物学院创新楼B-437

Johan Kotze副教授

I will briefly introduce a research proposal which our team is currently developing, with the aim of including four cities: Lahti (Finland), Seoul (South Korea), Shanghai and Shenyang (China). Urban greenspace is aesthetically-pleasing for the enjoyment and health benefits of urban residents. But, are these greenspaces environmentally safe – and sustainable – especially given that they often reside in highly polluted urban settings? Herein lies a conundrum; people are more disconnected from nature than ever before due to rapid urbanisation, yet connecting to urban nature may not necessarily have health benefits if highly polluted. The focus of this proposal is three-fold; i) the characterization of toxicants (including metals), and ii) the microbial community (‘missing beneficial microbes’) in soils across urban-rural gradients in highly-polluted cities in Asia, and iii) the use of traits in an insect group, here carabid beetles, as indicators of pollution stress and thus soil health.

Urban trees: what do we know about the services they provide?

2019-09-16　14:30 — 16:00

农业与生物学院创新楼B-437

Heikki Setälä 教授

The influence of plant type (grass/lawn, evergreen trees, deciduous trees) on soils and their ecosystem services (ESS) was studied in 41 parks of varying ages in two cities in Finland. Soils were sampled for physical-chemical-biological properties and heavy metals close to each plant type up to a 50 cm depth. Air quality was monitored in near-road environments in tree-covered and open areas. We hypothesize that 1) plant types, especially conifers, modify the soils differently resulting in divergent ESS between plant types, and (2) that air is cleaner under tree canopies compared to open areas.

Urban vegetation, particularly evergreen trees, had a clear effect on soil quality: they lowered soil water content and pH and increased soil organic matter, carbon and nitrogen sequestration compared to lawns. Also metal and nutrient pools and their mobility in the park soils was influenced by plant traits. We showed that, despite the ability of trees to reduce concentrations of road dust, urban trees seem ineffective (PM2.5), and even increase the levels of traffic-derived gaseous pollutants (NO2, VOCs, PAHs). These studies suggest that urban trees can be important in the provision of ESS, but that managing urban greenspace for better ESS provision requires specific knowledge on, e.g. plant types and the spatial structure of greenspaces within urban landscapes.

以学习为中心的教学设计

2019-09-17　13:00 — 14:30

Middle Lecture Room(703)

梁竹梅

演讲人简介：梁竹梅，博士，上海交通大学教学发展中心教学咨询员，主要从事教学咨询和培训开发工作。主持的教学系列工作坊有：以学习为中心的教学设计、教学档案袋建设、基于课程和课堂的“教学活动设计”、主动学习策略、大班教学中促进学习的实践原则及策略、BOPPPS方法与实践、促进学生自主学习以及概念图、思维导图在教学中的应用。研究方向包括教师教学行为、教学学术以及教学咨询与评估。

Symmetries of Ordinary Differential Equations (II)

2019-09-17　14:00 — 15:00

Large Conference Room(706)

Sebastian Walcher

These lecture notes provide an introduction to the theory and application of symmetry methods for ordinary differential equations, requiring only minimal prerequisites. Their purpose is mostly to provide a quick approach for nonspecialists; they are certainly not intended to replace any of the monographs on this topic. There is a certain emphasis on ODEs of first order here, which are less prominently featured in most standard texts. The notes are organized as follows. Chapter 1 contains basic and introductory material on ODEs with analytic right hand side, much of which is probably known to the reader. (Some remarks address differential equations with smooth right hand side, pointing out similarities and differences.) Chapter 2 contains Sophus Lie’s classical theory of local one-parameter symmetry and orbital symmetry groups in the context of first order (mostly autonomous) equations, with a short digression to second order equations. Chapter 3 deals with “multiparameter symmetries” (including a clarification notions), and with invariant sets that are (so to speak) forced by symmetries. In Chapter 4 the table is turned: We start with a given (linear) group and discuss differential equations that admit this group as a group of symmetries, with an emphasis on toral groups. We then discuss Poincar´e-Dulac normal forms as a special class admitting toral symmetry groups.

Stability of smooth soliton for the Degasperis-Procesi equation

2019-09-17　15:00 — 16:30

Large Conference Room(706)

李骥，华中科技大学

The Degasperis-Procesi equation is an approximating model of shallow-water wave propagating mainly in one direction to the Euler equations. Such a model equation is analogous to the Camassa-Holm approximation of the two-dimensional incompressible and irrotational Euler equations with the same asymptotic accuracy, and is integrable with the bi-Hamiltonian structure. In the present study, we study the stability issue of the localized smooth solitons to the Degasperis-Procesi equation on the line. Using refined estimates of the related bi-linear form, we prove that all these smooth solitons are spectrally and orbitally stable under small perturbations in the energy space.

半导体量子结构中的自旋轨道耦合和量子相

2019-09-18　15:00 — 16:00

理科楼5号楼203

常凯，中科院半导体所超晶格国家重点实验室

半导体物理与技术是现代通信和信息处理的基础。但随着半导体器件集成度的提高,功耗和散热问题成为未来电子器件的障碍。半导体电子自旋为低功耗的信息处理和存储提供了新的自由度。半导体量子结构中的自旋轨道耦合为全电控的半导体自旋器件提供了物理基础。半导体量子结构中的自旋轨道耦合不仅具有重要的应用价值，同时导致形形色色的自旋相关的量子效应，它可以把维度效应、关联效应和能带结构结合起来，诱导出新量子相。在本次报告中，我们将结合我们的工作讨论在近年来在半导体量子结构中呈现出的自旋轨道耦合及其诱导的量子效应和量子相；例如：1，半导体极性界面对能带的调控；2，自旋轨道耦合效应及其诱导的规范场和自旋霍尔效应；3，半导体量子阱中库仑关联引致的激子绝缘相。

A few properties of global solutions of the heat equation on Euclidean space and some manifolds

2019-09-19　15:00 — 16:00

Middle Lecture Room(703)

Prof. Qi S. Zhang，Department of Mathematics, UC, Riverside

We report some recent results on Martin type representation formulas for ancient solutions of the heat equation and dimension estimates of the space of these solutions under some growth assumptions.

We will also present a new observation on the time analyticity of solutions of the heat equation under natural growth conditions. One application is a if and only if solvability condition of the backward heat equation, i.e. under what condition can one turn back the clock in a diffusion process.

Part of the results are joint work with Fanghua Lin and Hongjie Dong.

【文俊讲坛】听音辨群

2019-09-19　16:00 — 17:00

Middle Lecture Room(706)

王杰，北京大学

通过旋律与对称、勋伯格十二音技术以及新黎曼理论（neo-Riemannian theory）等方面的若干实际，介绍音乐与群论之间密切的，往往又不为人知的内在联系。

Liouville properties of the Navier-Stokes

2019-09-20　15:30 — 16:30

Large Conference Room(706)

Zhen Lei，Fudan University

We establish a Liouville theorem for bounded ancient mild solutions to the axi-symmetric incompressible Navier-Stokes equations on $(-\infty, 0] \times (\mathbb{R}^2 \times \mathbb{T}^1)$. Connecting the compactness of $\mathbb{T}^1$ to the oscillation of the stream function is a crucial observation.

Does the ratio of Laplace transforms of powers of a function identify the function?

2019-09-20　16:30 — 17:30

Large Conference Room(536)

袁玲龙，西交利物浦大学

We study the following problem. Let m, n be two distinct nonnegative integers and f a nonzero measurable function on [0,∞) of at most exponential order. Let H_(n,m):=L(f^n)/L(f^m) be the ratio of the Laplace transforms of f^n and f^m. Does knowledge of the function H_(n,m) uniquely specify the function f? This is a generalization of Lerch's theorem (Laplace transform specifies the function). Under some rather strong assumptions on f we show that the answer is affirmative. This problem finds applications in auction theory where one is interested in identifying the distribution of bids based on the distribution of the highest ones. This is a joint work with Takis Konstantopoulos.

千禧年七大数学难题之一：Navier-Stokes 方程的历史渊源

2019-09-20　16:30 — 17:30

Large Conference Room(706)

徐超江，南京航空航天大学

2000年五月Clay数学研究所在法兰西学院公布了七个“千年大奖问题”，每个问题的解决可以获得Clay研究所的一百万美元的奖金。本综合报告将面向数学专业的大学生和研究生，介绍这七大难题之一的Navier-Stikes方程的历史渊源。Navier-Stikes方程是流体力学的最基本的数学物理方程，我们将从阿基米德的浮力学理论开始追溯两千多年来这个方程的历史渊源，最后简单的介绍一些最新的研究进展。

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