Normalized metrics

Normalized metrics can produce ratios that provide better context for comparison across multiple sites, companies, or industry segments. Such metrics can also be useful in one-to-one performance benchmarking. Normalized data provides a rate expression for process safety performance and can be used to compare performance among sites that differ in size and processing technology as well as performance comparisons among companies within an industry or even across industries. There are a number of ways to normalize process safety data, and methods include, but are not limited to ... 

Normalized performance data can facilitate sharing performance results both internally and externally. Using a consistent metrics basis, normalized data can aid in performance comparisons across an organization that consists of multiple sites and facilities. At the site level, multiple units can be compared using metrics of interest. Several industry and professional organizations sponsor the sharing of normalized metrics to determine the overall performance trend by industry segments. 

In contrast to percent normal metrics, z-scores take into account variability within the selected reference population. Subject Y s performance is expressed in terms of the difference between it and the reference population mean, normalized by a value corresponding to one standard deviation unit (a) of the reference population distribution ... 

Sohd ammonium sulfide decomposes to ammonia and ammonium hydrosulfide at about — 18°C consequently it is normally marketed as a 40—44% aqueous solution. In June 1991 the price was 507 per metric ton. 

Normally, zircon sand is readily available as a by-product of mtile and ilmenite mining at ca 150 per metric ton. However, zircon and baddeleyite are obtained as by-products of their operations, and therefore, the supply is limited by the demand for other minerals. In 1974, when a use for zircon in tundish nozzles developed in the Japanese steel industry, a resulting surge in demand and stockpiling raised zircon prices to 500/t. Worldwide production by country is given in Reference 80. 

In most diying operations, water is the liquid evaporated and air is the normally employed purge gas. For diying purposes, a psychro-metric chart found very useful is that reproduced in Fig. 12-36. 

The belt conveyor is almost universal in apphcation. It can travel for miles at speeds up to 5.08 m/s (1000 ft/min) and handle up to 4539 metric tons/h (5000 tons/h). It can also operate over short distances at speeds slow enough for manual picking, with a capacity of only a few Idlograms per hour. However, it is not normally apphcable to processing operations, except under unusual conditions. 

It is presumptuous to report that a substance is not hydrated simply because there are no drifts in the readings obtained during potentio-metric measurements or because the experimentally determined p a value is not very different from the predicted value. A small amount of hydration may cause only a small difference in the ionization constant and hence other tests should be applied. A number of heterocyclic compounds which have seemingly normal pvalues may well be partially hydrated. 

For larger and more complex boiler plants, where spectrophoto-metric tests are the norm, the presence of a brown color may cause interference, but these normally are dealt with quite easily. 

Rivers transport suspended sediments derived from the disintegration of basin surface layers. With reduced velocity, sediment is deposited in the river channel. The finest material is carried to the sea. It has been estimated that the average mechanical denudation rate for continents is 0.056 mm year (35). This is based on a total suspended load of 13.5 x 10 metric tons year (S). Presently, about two-thirds of the world s total suspended sediment load derives from Southern Asia and large Pacific Islands. Berner has estimated the increase in sediment loss in the U.S. and world since prehuman times to be approximately 200% (35). Current estimated erosion rate from the major land forms is provided in Table I. The relatively recent construction of large sediment trapping dams that normally caused sediment to be deposited in river valleys or transported to the ocean has drastically reduced sediment yields in great rivers. 

The degree of vibrational excitation in a newly formed bond (or vibrational mode) of the products may also increase with increasing difference in bond length (or normal coordinate displacement) between the transition state and the separated products. For example, in the photodissociation of vinyl chloride [9] (reaction 7), the H—Cl bond length at the transition state for four-center elimination is 1.80 A, whereas in the three-center elimination, it is 1.40 A. A Franck-Condon projection of these bond lengths onto that of an HCl molecule at equilibrium (1.275 A) will result in greater product vibrational excitation from the four-center transition state pathway, and provides a metric to distinguish between the two pathways. 

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