China In 1982, Liu received a bachelor's degree in modern mechanics from the
University of Science and Technology of China. He was employed by the
Aviation Industry Corporation of China in
Shenyang in the field of
aerodynamics. He worked in partnership with
Luo Yang, and was promoted to head of
aircraft design. Liu's field of research was the theory of
air resistance, and he worked on problems of double-sided entry and
radar technology. In 1984, Liu received a master's degree in
optics from the Department of Physics at
Peking University in
Beijing. While there, he was an assistant teacher. Liu returned to work at the China Soft Science Research Institute but was also acting assistant director at the University of Science and Technology of China. In 1988, Liu became an assistant and associate researcher at the Wear-Resistant Materials Development Company of the National Ministry of Higher Education and the
Dalian Institute of Technology. He was then transferred to research in the Department of Physics at the
Chinese Academy of Sciences.
United States In 1996, Liu received a master's degree in computer science from Columbia University. He was invited to speak at the
New York Academy of Sciences. Liu gained employment as a member of technical staff (MTS) at the Mathematics of Networks and Systems Research Department at Bell Laboratories in
Murray Hill, New Jersey. There he worked on
Optical telecommunication network design and planning,
routing algorithms,
optimization techniques, and
economic models and
strategy analysis. Liu's areas of research included: SPIDER, a design tool for fast-restoration in all-optical networks; VPNStar, a system for provisioning multi-service
VPNs with
Quality of service guarantees over
Internet Protocol; in software design, a management system for Lambda Router in all-optical networks; and analysis of
Internet pricing. During his days at Bell Laboratories, Liu introduced the A*Prune (1999, ) with K. G. Ramakrishnan, to describe a new class of
algorithm. This opened a new research direction in
theoretical science. He found that A*Prune is comparable to the current best known-approximate algorithms for most randomly generated
graphs. The algorithm constructs paths, starting at the source and going towards the destination. But, at each iteration, the
algorithm is rid of all paths that are guaranteed to violate the constraints, thereby keeping only those partial paths that have the potential to be turned into feasible paths, from which the
optimal paths are drawn. Liu also proposed a special class of Optical devices called SPIDER (2001, ); optical routers, dense
wavelength division multiplexing (DWDM) systems, and cross-connects of unprecedented capacities. Liu and his colleagues are developing techniques for efficient and reliable
optical network design, covering decentralized dedicated protection to shared path-based mesh restoration. ==References==