Ya-xiang Yuan of the Chinese Academy of Sciences was awarded the 2017 SIAM Prize for Distinguished Service to the Profession
at the SIAM Annual Meeting
(AN17) held July 10-14, 2017 in Pittsburgh, Pennsylvania.
SIAM awards its Prize for Distinguished Service to the Profession every year to an applied mathematician who has made distinguished contributions to the advancement of applied mathematics on the national or international level. SIAM recognized Professor Yuan for his extraordinary achievements in developing and promoting applied mathematics in general, and optimization in particular, in China.
Ya-xiang Yuan received his PhD in 1986 at the University of Cambridge, as a student of Michael J. D. Powell. From 1985-88, he was the Rutherford Research Fellow at Fitzwilliam College, Cambridge. Afterward, rather than pursuing a career at a top Western university, he returned to China, to the Academy of Sciences, and started to build a modern optimization community there. With enormous energy, he instructed numerous research students and then followed and supported their careers in universities throughout China. He organized many conferences and workshops at both the national and international level, argued for support of mathematics in China, and provided guidance to generations of young Chinese optimization professionals. As a result of his efforts, there is a thriving community of optimization professionals in China meeting high international standards. He was instrumental in bringing the International Congress on Industrial and Applied Mathematics (ICIAM) to Beijing in 2015. In 2017, he became President-Elect of ICIAM.
Ya-xiang Yuan is a professor in the Academy of Mathematics and Systems Science at the Chinese Academy of Sciences and is affiliated with its State Key Laboratory of Scientific and Engineering Computing (LSEC). He is currently President of the Chinese Mathematical Society, and Vice-President of the China Association of Science and Technology. He serves as Editor-in-Chief of Science China Mathematics and the Journal of the Operations Research Society of China. He was an ICIAM 1999 and International Congress of Mathematicians (ICM) 2014 invited speaker. He became one of the youngest Academicians of the Chinese Academy of Sciences in 2011. He is a corresponding member of the Brazilian Academy of Sciences and a fellow of The World Academy of Sciences (TWAS). He is a Fellow of both SIAM and the American Mathematical Society (AMS).
Professor Yuan works on numerical methods for nonlinear optimization. He has made outstanding contributions to trust region algorithms, quasi-Newton methods, nonlinear conjugate gradient methods and subspace methods.
Q: Why are you excited about winning the prize?
A: It is a great honor and great pleasure to receive this award, as many previous winners of this award are famous scientists that I admire.
Q: Could you tell us a bit about the research that won you the prize?
A: My major research topics are trust region algorithms, nonlinear conjugate gradient methods, quasi-Newton methods and subspace methods. Trust region algorithms are a class of numerical methods for optimization, which do not need to carry out line search. They have the advantage of handling ill-conditioned problems. Pioneer researchers on trust region algorithms include scientists such as the late professors Michael J. D. Powell and Roger Fletcher. I am very happy that I provided the optimality conditions for the Celis-Dennis-Tapia subproblem and proved the "1/2" conjecture of the Steihaug-Toint truncated conjugate gradient method.
Q: What does your research mean to the public?
A: I work on numerical methods for optimization. Optimization is a subject that is widely and increasingly used in science, engineering, economics, management, industry, and many other areas. Many big data problems can be formulated as optimization problems. My research aims to provide efficient numerical methods for solving different optimization problems and to give theoretical results on the properties of optimization methods which can help people to understand various methods better and help users to choose suitable algorithms for particular real-world problems.
Q: What does being a SIAM member mean to you?
A: It means a lot to me to be a SIAM member. As a SIAM member, I can attend more academic conferences organized by SIAM, and membership in SIAM has helped me to establish a better connection with colleagues all over the world. I was elected as a SIAM Fellow in 2011, and this has facilitated my election to the Chinese Academy of Sciences and later to other academies.