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Reliability 3 0 0 INDEX

The FORM allows us to estimate the index reliability p and to calculate the failure probabiUly Pf = cumulative distribution function of the normal distribution. We compare the reliability index at the current iteration with that of the previous iteration as follows ... [Pg.1344]

Molecular descriptors must then be computed. Any numerical value that describes the molecule could be used. Many descriptors are obtained from molecular mechanics or semiempirical calculations. Energies, population analysis, and vibrational frequency analysis with its associated thermodynamic quantities are often obtained this way. Ah initio results can be used reliably, but are often avoided due to the large amount of computation necessary. The largest percentage of descriptors are easily determined values, such as molecular weights, topological indexes, moments of inertia, and so on. Table 30.1 lists some of the descriptors that have been found to be useful in previous studies. These are discussed in more detail in the review articles listed in the bibliography. [Pg.244]

Selection of a name for a specific compound is heavily influenced by the purpose at hand communication to a general audience, communication with specialists, or storage/retrieval through archival indexes. The first requires the simplest rules possible the second requires the shortest names possible and the third requires rigid adherence to a set of rules that will reliably generate a unique name. The name chosen may be different for each situation, although that is not necessarily so. [Pg.35]

Rosyid, D. M. 1992 Elemental Reliability Index-Based System Design for Skeletal Structures. Structural Optimization, 4(1), 1-16. [Pg.391]

To help the reader select the appropriate data resource, an index precedes Sections 4.3 through 4.8. The index provides the source number within the section and the following set of data elements for each source title, industry, number and type of records, and data boundary. Appendix C contains additional information about the data elements presented in each data resource. It can also be used to help identify the resources which may provide data for a CPQRA. A discussion of the Appendix C Matrix and an explanation of data elements indexed is presented. After examining Appendix C and the pattern of data elements contained in the data resources, it is evident that equipment reliability data have been published in a variety of formats, often without any apparent effort to conform to a recognized standard for data specification. The CCPS Taxonomy and the raw data collection requirements in Chapter 6 present the basis for reliability data specification in future literature. [Pg.29]

A number of indices relate metal activity to hydrogen and coke production. (These indices predate the use of metal passivation in the FCC process but are still reliable). The most commonly used index is 4 X Nickel + Vanadium. This indicates that nickel is four times as actiw as vanadium in producing hydrogen. Other indices [9] used are ... [Pg.63]

Although the Langelier index is probably the most frequently quoted measure of a water s corrosivity, it is at best a not very reliable guide. All that the index can do, and all that its author claimed for it is to provide an indication of a water s thermodynamic tendency to precipitate calcium carbonate. It cannot indicate if sufficient material will be deposited to completely cover all exposed metal surfaces consequently a very soft water can have a strongly positive index but still be corrosive. Similarly the index cannot take into account if the precipitate will be in the appropriate physical form, i.e. a semi-amorphous egg-shell like deposit that spreads uniformly over all the exposed surfaces rather than forming isolated crystals at a limited number of nucleation sites. The egg-shell type of deposit has been shown to be associated with the presence of organic material which affects the growth mechanism of the calcium carbonate crystals . Where a substantial and stable deposit is produced on a metal surface, this is an effective anticorrosion barrier and forms the basis of a chemical treatment to protect water pipes . However, the conditions required for such a process are not likely to arise with any natural waters. [Pg.359]

The comparatively straightforward link between 5-HT and its primary metabolite, 5-HIAA, encouraged many researchers to use changes in the ratio of tissue concentrations of 5-HIAA and 5-HT as an index of the rate of release of 5-HT ex vivo. However, it has been clear for some time that the majority of 5-HT is metabolised in the cytoplasm by MAO before it is released from 5-HT nerve terminals. Consequently, the reliability of the 5-HIAA 5-HT ratio as an index of transmitter release is rather dubious, although it could be used as an acceptable measure of MAO activity. In any case, the development of in vivo microdialysis means that changes in the concentration of extracellular 5-HT can now be monitored directly which, under drug-free conditions, provides a far more reliable indication of any changes in the rate of release of 5-HT. [Pg.197]

Accurate interpretation of the formation properties (porosity, permeability and irreducible water saturation) requires reliable estimates of NMR fluid properties or the relationship between diffusivity and relaxation time. Estimation of oil viscosity and solution-gas content require their correlation with NMR measurable fluid properties. These include the hydrogen index, bulk fluid relaxation time and bulk fluid diffusivity [8]. [Pg.324]

Sample preparation, injection, calibration, and data collection, must be automated for process analysis. Methods used for flow injection analysis (FLA) are also useful for reliable sampling for process LC systems.1 Dynamic dilution is a technique that is used extensively in FIA.13 In this technique, sample from a loop or slot of a valve is diluted as it is transferred to a HPLC injection valve for analysis. As the diluted sample plug passes through the HPLC valve it is switched and the sample is injected onto the HPLC column for separation. The sample transfer time typically is determined with a refractive index detector and valve switching, which can be controlled by an integrator or computer. The transfer time is very reproducible. Calibration is typically done by external standardization using normalization by response factor. Internal standardization has also been used. To detect upsets or for process optimization, absolute numbers are not always needed. An alternative to... [Pg.76]

Norepinephrine is a potent a-adrenergic agent with less pronounced P-adrenergic activity. Doses of 0.01 to 3 mcg/kg per minute can reliably increase blood pressure with small changes in heart rate or cardiac index. Norepinephrine is a more potent agent than dopamine in refractory septic shock.24,27-28... [Pg.1194]

The results of the DFR assessment of different crop zones indicate that low-volume applications result in a more homogeneous distribution over the crop compared to high-volume applications. A recent study on the interception of high-volume applications in the cultivation of chrysanthemums revealed interception ratios from 0.2 to 1 related to the leaf area index (LAI) (Veerman et al., 1994). In our study, it was not easy to assess the LAI because of the structure of the carnation crop. Estimation of the LAI based on the results of estimation of the crop density (leaf volume index) was not reliable enough and resulted in a large variance of the calculated interception ratio (from 0.4 up to 5). [Pg.134]


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See also in sourсe #XX -- [ Pg.17 , Pg.18 , Pg.20 , Pg.21 , Pg.28 ]

See also in sourсe #XX -- [ Pg.763 , Pg.961 , Pg.962 , Pg.963 , Pg.964 , Pg.965 , Pg.966 , Pg.967 , Pg.968 , Pg.969 , Pg.970 , Pg.971 , Pg.972 ]




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