DAAD校友聚焦研讨会 “数学和应用数学” 暨
中国留德学人数学与应用数学学会2013年学术交流年会
(Alumni Fokus: Fachseminar Mathematik und ihre Anwendungen &
GCMA Jahrestagung 2013)

地点：德国，斯图加特(Stuttgart)
日期：2013年11月23至24日

主办：
德意志学术交流中心（DAAD，www.daad.de）
中国留德学人数学与应用数学学会（GCMA，www.gcma-ev.de）

会议报道
　　在经历了6年的风雨兼程之后，中国留德学人数学与应用数学学会终于在11月23，24日两天在Tagungshotel Commundo Stuttgart迎来了自己2013年第六界学术交流年会。本届学术交流年会在DAAD赵潇先生的全力支持配合下无论是在与会者规模还是在交流深度上都达到了一个新的维度。与会的50多名来自德国各大城市的专家学者博士及硕士研究生就11篇年会报告以及在德国就读博士学位的前景展望工作机会等热门话题展开了激烈的讨论。23号晚的聚餐更是提供了每个与会者一个面对面交流和深入探讨的机会。

　　2013年11月23日周六上午13:30 赵潇先生的欢迎词揭开了中国留德学人数学与应用数学学会2013年第六界学术交流年会的帷幕。本届年会的主题是德中两国科学与技术的跨文化传播，正式报告部分在来自KIT的研究员陈学农博士的特邀报告“我在孤立波方面的研究”后陆续展开，分别由来自柏林科技大学、海德堡大学、哥廷根大学以及卡尔斯鲁厄研究院的10位在读博士生作出报告，在年会限定的十分钟的答疑讨论环节与会者就演讲课题参与了积极的讨论并作出了反馈，反响极佳。

　　为了更好的方便与会学员的交流和讨论，DAAD与中国留德学人数学与应用数学学会增加了三个重要的环节，已然成为本届年会的亮点。增加的第一环节是23日下午16:30-18:00展开的数学和相关专业毕业生工作经验交流的问答讨论互动环节，由特邀嘉宾劳维博士，范奕骏先生，冼军教授和陈学农研究员四人共同主持。与会者就在德博士的学术期盼和就业展望问题提出了自己感兴趣的问题，并展开了积极的讨论，该互动环节受到了此次年会参与者的好评。增加的第二环节为23日第一天报告结束后的DAAD赵潇先生主持的聚餐以及为非斯图加特学员提供的住宿。聚餐为与会学员在仅有短暂的两天报告期间提供了增强彼此间的交流与认识的机会。很多学员甚至讨论到当天晚上11点半才纷纷回到住处。增加的第三环节为24早9:00至9:30的数学学会2013年年会。理事长陈琪博士致欢迎词，并向所有与会者作了2013年度的学会工作报告与财务报告，以及学会2007年创办以来历年的活动事项，其清晰度和透明度吸引了到场的许多非数学学会学员，不少与会者当场填写了入会申请表。

　　活动在最后李厚霖先生的实施核磁共振成像中的图像重构问题的报告中顺利进入尾声。但是在德中国科研人员想要传播跨文化科技交流的热情未减。在祖国正积极思考自己的文化与科技的国际地位和定位的关键历史时期，本届年会更是赋予了特别的意义和历史使命。希望本着学术和科研精神的中国留德学人数学与应用数学学会学术交流年会能继续传承下去，为中国留德留学人员带来更多更到位的资讯和帮助。

中国留德学人数学与应用数学学会理事会
2013年12月

会议日程
11月23日 周六  
11:00-13:00 报到
13:30-13:40 会议组织者致欢迎词
13:40-14:00 报告1：Deutschland-Alumni China: Interkulturelle Talente，赵潇 先生（DAAD）
14:00-14:30 特邀报告：我在孤立波方面的研究 陈学农 研究员（KIT）
  第一主题 数学在工业中的应用
14:30-14:55 报告3：湍流燃烧的直接数值模拟 张飞驰 先生（KIT）
14:55-15:25 休息，合影
15:25-15:50 报告4：费希尔信息矩阵与CRLB在二维空间定位中的特性分析 赵毓斌 先生（FU Berlin）
15:50-16:15 报告5：空间几何信息在定位算法和评估中的应用 阳媛 女士（FU Berlin）
16:15-16:30 休息
  第二主题 数学和相关专业毕业生工作经验交流
16:30-18:00 问答讨论互动环节。特邀嘉宾：劳维 博士 (d-fine GmbH)，范奕骏 先生 (cormeta AG)，冼军 教授（中山大学）， 陈学农 研究员（KIT）
18:00-21:00 晚餐
11月24日 周日  
08:00-09:00 早餐，退房
09:00-09:30

数学学会
会员大会		 • 理事会致欢迎辞
• 确定会员大会的记录员
• 2013年度学会工作报告
• 2013年度学会财务报告
• 学会其它议题的讨论
• 记录所有出席会议的会员并请求签名
  第三主题 数学在信息学中的应用和纯数学
09:30-10:00 特邀报告：Shannon Sampling Theorem in Information Theory and Its Application 冼军 教授（中山大学）
10:00-10:25 报告7：A very brief introduction to circle packings and sphere packings 陈浩 先生（FU Berilin）
10:25-10:50 报告8：关于Goss Zeta函数的一些性质 邱予嘉 女士（Uni. Heidelberg）
10:50-11:20 休息
  第四主题 数学在医学领域中的应用
11:20-11:45 报告9：光学干涉断层扫描引导下的激光耳蜗切开术 张耀坤 先生（KIT）
11:45-12:10 报告10：血管中动脉粥样硬化斑块的形成和演化的数学建模和数值模拟 杨一帆 先生（Uni. Heidelberg）
12:10-12:35 报告11：实时核磁共振成像中的图像重构问题 李厚森 先生（Uni. of Göttingen and Max Planck Institute for Biophysical Chemistry）
12:35-13:00 自由讨论，尾声
13:00 会议结束

学术报告摘要见附录。

附录：学术报告摘要

我在孤立波方面的研究
(My Researches on Solitary Waves)

陈学农 博士，研究员 (KIT)

Solitary waves are a particular phenomenon in the nonlinear physical world, which attract significant attentions from the mathematical side. It is quite accident this phenomenon goes through my academic life. In this talk I would like introduce three examples that I’ve researched in quite different fields, namely (i) chaotic soliton motion; (ii) waveless ship form generated by a two-soliton solution; (iii) travelling wave reactor. I would like not only to present the results, but also necessary background information.

湍流燃烧的直接数值模拟
(Direct Numerical Simulation of Turbulent Combustion)

张飞驰 (KIT)

报告摘要

费希尔信息矩阵与CRLB在二维空间定位中的特性分析
(Analysis of Fisher Information matrix and Cramer-Rao lower bound for 2D geometric localization)

赵毓斌 (FU Berlin)

费希尔信息矩阵是信息论和几何信息学中重要的公式之一。本文将通过费希尔矩阵描述在二维空间定位中的空间误差分布，进而分析其在二维空间的特性，指出了采用费希尔矩阵分析最优估计器性能的局限。根据这些特性，本文引入三维空间因素——相对高度差，对费希尔矩阵进行修正，使之能更准确的分析二维空间定位算法。最后，我们通过空间误差分布的分析方法，比较了不同定位算法的估计的准确度，并对其鲁棒性进行了分析。

空间几何信息在定位算法和评估中的应用
(Spatial Geometric Information for Position Estimation and Performance Evaluation)

阳媛 (FU Berlin)

As the prevalent of mobile devices (i.e., smart phone, tablet and PDA),mobile target positioning or LBS (Location Based Service) have attracted a lot of attention lately.Various positioning techniques have be investigated,i.e., GPS, cellular network positioning, radio positinging by sensor networks, WLAN, computer-vision systems, or map matching, etc. All such positining techniques involve geometric information in nature.

Geometric information provides a straightforward solution for localization. This paper reviews some positioning algorithms which empore the geometric information. Furthermore, we propose a geometric performance evauation using two dementional spatial distribution analysis based on Monte Carlo simulations.

Keywords : Geometric localization, the NLOS error, Monte Carlo simulation, geometric performance evaluation

Shannon Sampling Theorem in Information Theory and Its Application

冼军 教授 (中山大学)

报告摘要

A very brief introduction to circle packings and sphere packings

陈浩 (FU Berlin)

The talk consists of two parts:

The first part is dedicated to Koebe--Andreev--Thurston’s circle packing theorem : any planar graph can be realized by the tangency relations of a circle packing. After reviewing some history, I will point out the relation between circles packings and conformal maps, which leads to applications in computer modelling.

In the second part, I will go to higher dimensions yet retreat to spheres of same radius, and talk about packings of n-dimensional spheres of same radius. I will tell the legend of kissing numbers and Kepler conjecture. Studies on related problems, though purely theoretic, find applications in coding theory.

In the last few minutes, I will mention the topic of my own research: packing of spheres of various radius.

关于Goss Zeta函数的一些性质
(On Some Properties of Goss Zeta Function)

邱予嘉 (Uni. Heidelberg)

报告摘要

光学干涉断层扫描引导下的激光耳蜗切开术
(Optical Coherence Tomography guided Laser-Cochleostomy)

张耀坤 (KIT)

耳蜗切开术是人工耳蜗植入手术的重要步骤。在手术过程中，必须在保证耳蜗的鼓管内膜不受损伤的情况下将其上所有的骨组织切除。相比传统的手术工具如钻、锯等，短脉冲二氧化碳激光可以不施加外力的情况下进行手术，同时也更加精确。但是在手术中如何实时探测鼓管内膜的位置在以前的工作中没有得到有效的解决。本文介绍了利用光学干涉断层扫描技术 OCT(optical coherence tomography) 对耳蜗切开过程进行监测的方法，实现对二氧化碳激光进行闭环控制，从而使切开过程自动化，在提高手术成功率的同时降低手术医生的负担和风险。

Cochleostomy is a vital step of cochlea implantation, during which the cochlear lining membrane has to be reserved while a complete removal of the overlaying bone tissue is required. Compared wich conventional mechanical tools like burr or saw, a short-pulsed CO2 laser enables a bone ablation without any mechanical stress to the delicate structures and a higher accuracy. However, how to detect the position of the cochlear lining membrane intra-operatively is still an open question. This work aims on monitoring the laser-cochleostomy using OCT (optical coherence tomography) and establish a closed-loop control of the CO2 laser. An automatic procedure of ablation is realized, which increases the patient safety and reduces the risk of the surgery simultaneously.

血管中动脉粥样硬化斑块的形成和演化的数学建模和数值模拟
(Mathematical modeling and simulation of the formation and evolution of plaques in blood vessels)

杨一帆 (Uni. Heidelberg)

The evolution of plaques is one of the main causes for the blockage of arteries. This can lead to ischaemic brain or myocardial infarctions as well as other cardiovascular diseases. Possible biochemical and biomechanical processes contribute to the development of plaque growth and rupture. The main biochemical processes are the penetration of monocytes and the accumulation of foam cells in the vessel wall, leading to the formation and growth of plaques. The biomechanical forces can be measured by observing stresses in the blood flow and the vessel wall, which may lead to the rupture of plaques.

In this talk, we formulate an appropriate model to describe the evolution of plaques. The model consists of both the interaction between the blood flow and the vessel wall, and the growth of plaques due to the penetration of monocytes from the blood flow into the vessel wall. The Navier-Stokes equations and the elastic structure equations are used to describe the dynamics of fluid (blood flow) and the mechanics of structure (vessel wall). The motion of monocytes is described by the convection-diffusion-reaction equation, coupled with an equation for the accumulation of foam cells. Finally the metric of growth is introduced to accurately determine the stress tensor, and its evolution equation is derived. The variational formulation of the model is transformed into the ALE (Arbitrary Lagrangian-Eulerian) formulation, and all the equations are rewritten in the fixed domain. Temporal discretization is achieved with finite differences and spatial discretization is based on the Galerkin finite element method. The nonlinear systems are linearized and solved by the Newton method.

Based on the model and the numerical methods above, numerical simulations are performed by using the software Gascoigne. The obtained numerical results make an agreement with the observation, and support the assumption that the penetration of monocytes and the accumulation of foam cells lead to the formation and growth of plaques, and that the evolution of plaques induces the increase of stresses in the vessel wall, which is an indicator of plaque rupture.

实时核磁共振成像中的图像重构问题
(Image Reconstruction in Real-Time MRI)

李厚森 (Uni. of Göttingen and Max Planck Institute for Biophysical Chemistry)

Imaging speed is crucial in real-time magnetic resonance imaging (MRI) studies of physiological processes, such as cardiovascular dynamics. Because of physical and physiological limitations, most methods generally shorten the measuring time by acquiring less data than would normally be needed according to the sampling theorem. The goal of our research is to reconstruct a serial stream of images with high spatial and temporal resolution from such undersampled data. The methodology we adopt is to implicitly increase the sampling rate by incorporating a “self-navigating” estimation of the motion of objects. In the talk, we will present some basic concepts, strategies and challenges in image reconstruction as well as our recent developments.

Keywords : Statistical Inverse Problems, Aggregation Estimation, Medical Imaging.