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When a transition fault test set leaves undetected transition faults because of logic redundancies, test constraints, or the existence of hard-to-detect faults, it leaves transition fault sites uncovered. For the case where multicycle tests are used, this paper explores the possibility of covering the sites of undetected transition faults by using tests for what are referred to as optimistic unspecified transition faults. For this discussion, a standard transition fault is associated with an extra delay of a single clock cycle. An unspecified transition fault captures in a single fault the behaviors of transition faults of different durations. Because faults with different durations may be detectable or undetectable independently by a multicycle test, an unspecified transition fault may be detected even if the standard transition fault at the same site is undetectable. This effect is enhanced with optimistic unspecified transition faults. The paper describes an iterative test compaction procedure for multicycle tests that supplements the set of standard transition faults with optimistic unspecified transition faults to cover the sites of undetected standard transition faults.
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This content will become publicly available on June 1, 2026
Slab dynamics linked to transient weakening during mineral phase transitions
New experiments shed light on the complex interplay between rock deformation and metamorphism. Slab stagnation in Earth’s mantle transition zone may be explained by transient weakening during the olivine–spinel phase transition.
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- Award ID(s):
- 2023128
- PAR ID:
- 10634330
- Publisher / Repository:
- Nature Publishing Group
- Date Published:
- Journal Name:
- Nature Geoscience
- Volume:
- 18
- Issue:
- 6
- ISSN:
- 1752-0894
- Page Range / eLocation ID:
- 457 to 458
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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