Aspen Technology Fellow Chau-Chyun Chen Elected to National Academy of Engineering

February 16, 2005
Chen recognized for contributions to molecular thermodynamics and process modeling technology for industrial processes with complex chemical systems

CAMBRIDGE, Mass.--(BUSINESS WIRE)--Feb. 16, 2005-- Aspen Technology, Inc. (Nasdaq: AZPNE) today announced that Chau-Chyun Chen, a technology fellow at the company, has been elected to membership in the National Academy of Engineering. One of the highest honors in the engineering discipline, membership in the Academy is awarded to those who have made significant contributions to engineering theory and practice, and to those who have demonstrated extraordinary accomplishment in pioneering new and developing fields of technology. The Academy elected 74 new U.S. members and 10 foreign associates on February 11, 2005.

Chen was recognized for his contributions to molecular thermodynamics and process modeling technology for designing industrial processes with complex chemical systems. One of the founders of AspenTech in 1981, Chen was instrumental in developing the innovative first-principles modeling approach AspenTech brought to the chemicals industry. He also pioneered process modeling techniques for difficult chemical systems such as those that include electrolytes, as well as those that include large, complex molecules such as polymers and pharmaceuticals.

"We congratulate Chau-Chyun Chen on his election to the National Academy of Engineering," said Mark Fusco, President and CEO, AspenTech. "We are pleased that his work in process modeling, design and simulation - the cornerstones of AspenTech's business - has been acknowledged by the Academy with such a prestigious award. This distinct honor not only reflects his commitment to the field of engineering, but also recognizes the contributions he has made to AspenTech's customers as they look for innovative methods of modeling complex chemical systems."

Chen is the third of AspenTech's engineering experts to be elected to the Academy. Dr. Lawrence Evans, founder and former CEO, was elected in 2001; and Charles Cutler, former Senior Corporate Advisor, was elected in 2000.

Chen received ScD and MS degrees in chemical engineering from the Massachusetts Institute of Technology in 1980 and 1977, respectively, and a BS degree in chemistry from the National Taiwan University in 1973. He is the recipient of the 2001 Computing Practice Award, Computing and Systems Technology (CAST) Division of the American Institute of Chemical Engineers (AIChE); and serves on the editorial board of the International Journal of Fluid Phase Equilibria. He is a member of the American Chemical Society, the American Institute of Chemical Engineers, the American Association for the Advancement of Science, and the Chinese American Chemical Society.

About AspenTech

Aspen Technology, Inc. provides industry-leading software and implementation services that enable process companies to use simulation models to increase efficiency and profitability. aspenONE(TM), a new generation of software solutions from AspenTech, represents a major step forward in helping process manufacturers achieve their strategic operational excellence initiatives. The first comprehensive offering to address the demands of the Enterprise Operations Management (EOM) market, aspenONE provides companies with integrated systems that enable them to manage and optimize their operational performance. Over 1,500 leading companies already rely on AspenTech's software, including Aventis, Bayer, BASF, BP, ChevronTexaco, Dow Chemical, DuPont, ExxonMobil, Fluor, GlaxoSmithKline, Shell, and Total. For more information, visit www.aspentech.com.

AspenTech, aspenONE and the aspen leaf logo are trademarks of Aspen Technology, Inc., Cambridge, Mass.

CONTACT:
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Aspen Technology, Inc.
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Aspen Technology, Inc.
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