文档介绍：NASA/TM-2004-213499

A Hierarchical Approach to Fracture Mechanics
Erik Saether
Langley Research Center, Hampton, Virginia

Shlomo Ta'asan
Carnegie Mellon University, Pittsburgh, Pennsylvania

November 2004
The NASA STI Program Office . . . in Profile

Since its founding, NASA has been dedicated
to the advancement of aeronautics and space • CONFERENCE PUBLICATION. Collected
science. The NASA Scientific and Technical papers from scientific and technical
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part in helping NASA maintain this important
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The NASA STI Program Office is operated by programs, projects, and missions, often
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Program Office provides access to the NASA STI
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space science STI in the world. The Program Office is language translations of foreign scientific and
also NASA’s institutional mechanism for technical material pertinent to NASA’s mission.
disseminating the results of its research and
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includes the following report types: custom thesauri, building customized databases,
organizing and publishing research results ... even
• TECHNICAL PUBLICATION. Reports of providing videos.
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