UW math expert vanishes in China

Paul Tseng, a noted University of Washington mathematician and advanced math instructor, traveled to Southern China a couple of weeks ago to give a talk at an international conference. But conference organizers say he never showed up for his presentation.

UW colleagues fear he may have met with misadventure while kayaking on a river in the mountainous region of China's southwestern Yunnan Province.

The UW has enlisted the services of an international firm that specializes in overseas assistance, to aid in searching for Tseng. Chinese authorities also are searching.

In a statement released Monday, the UW's Office of News and Information said Tseng has been missing since Aug. 13.

UW spokesman Norm Arkans said Tseng, a UW faculty member since 1990, was invited to China to participate in the seventh annual International Conference on Numerical Optimization and Numerical Linear Algebra in the city of Lijiang on Aug. 17. The conference was hosted by the Chinese Academy of Sciences.

Local colleagues have described Tseng as an avid outdoorsman and seasoned kayaker. He is known to have kayaked solo on the Mekong River in Laos, the Nile in Egypt, the Danube in Germany and the Amazon in Peru in recent years.

Arkans said UW officials were told Tseng planned a kayaking trip on China's Jinsha River before his presentation. When he failed to appear at the conference, organizers notified Lijiang authorities.

The UW also retained consulting firm Control Risks, and search efforts have been under way for several days, Arkans said.

Colleagues say people reported seeing Tseng on the Jinsha River on Aug. 13 near Jinganqiao, an area described as very rugged, mountainous and isolated.

Arkans said there had been no contact from Tseng since then.

"His whereabouts remain unknown," Arkans said late Monday.

Born in Taiwan, Tseng lived in Canada with his family before gaining permanent U.S. residency status, the UW said. He holds a Canadian citizenship.

Arkans said Tseng earned his bachelor of science degree from Queen's University in Ontario in 1981 and his doctorate from the Massachusetts Institute of Technology in 1986. The field of optimization has been his specialty, said Selim Tuncel, chair of the UW's Mathematics Department.

Tseng is single, with no family ties in the Seattle area, Arkans said.

Charles E. Brown: 206-464-2206 or cbrown@seattletimes.com

The information in this article, originally published August 25, 2009, was corrected August 26, 2009. Selim Tuncel is chair of the University of Washington's Mathematics Department. A story Tuesday about missing mathematics instructor Paul Tseng incorrectly identified Tuncel as chair of the Applied Math Department. The same story referred to "China's northwestern Yunnan Province." The Yunnan Province is in southwestern China.