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Search methods failure

The RMDB consists of two mayor sections computer data storage and retrieval system, and backup microfilm data bank file. The computer data storage and retrieval system is used for die standard reliability and maintainability data listing, special calculations, and searches. This data bank system has been established to facilitate remote terminal access compatible with the GIDEP remote terminal programs. The microfilm data bank file is used for storage and distribution of supplier s documents, failure analysis curves, description of methods used in the collection of the data, and additional background information too extensive to include in the computer data bank. [Pg.153]

The hrst step in theoretical predictions of pathway branching are electronic structure ab initio) calculations to define at least the lowest Born-Oppenheimer electronic potential energy surface for a system. For a system of N atoms, the PES has (iN — 6) dimensions, and is denoted V Ri,R2, - , RiN-6)- At a minimum, the energy, geometry, and vibrational frequencies of stationary points (i.e., asymptotes, wells, and saddle points where dV/dRi = 0) of the potential surface must be calculated. For the statistical methods described in Section IV.B, information on other areas of the potential are generally not needed. However, it must be stressed that failure to locate relevant stationary points may lead to omission of valid pathways. For this reason, as wide a search as practicable must be made through configuration space to ensure that the PES is sufficiently complete. Furthermore, a search only of stationary points will not treat pathways that avoid transition states. [Pg.225]

Kuno and Seader [20] show how to use continuation methods to find all the solutions for a set of nonlinear equations. One simply continues past the first instance where t equals unity to find all other instances where it again equals unity. They show how to select a starting point for the search to guarantee that all solutions will be found. No proof exists for their method, but they have tested it extensively without a known failure. [Pg.514]

All evidence indicated that the cylinder ruptured due to the hydrostatic pressure of expanding liquid ammonia due to excessive heat on the cylinder. Fragments of the cylinder were sent to a testing laboratory for failure analysis. The ruptured cylinder was a full cylinder just put in service. According to the company s literature search, a full cylinder would become hydrostatically full of liquid ammonia at about 130° F (54.4° C). If the liquid was further heated, tremendous pressures would be developed. An alternate possibility was that the cylinder was heated to 250° F (121° C) (the steam supply temperature). Raising the temperature that high is unlikely with the crude heating methods and the expected heat losses, but if they were, the internal cylinder pressure could reach... [Pg.59]


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Methods failures

Search methods

Searching methods

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