Data exchange equivalent

Data exchange equivalence. First, we observe that the source instance U that is recovered by contains all the information that has been present in the original source instance I and has been exported by M". Indeed, if we now apply the mapping M" on U, we obtain via the chase an instance that is the same as J modulo null renaming (i.e., the chase may generate a different null C2 instead of ci). Thus, the following holds ... 

Definition 5. Let M be a GLAV schema mapping from Si to S2. Let 7 and I be two instances over Si. We say that I and / are data exchange equivalent with respect to M if chaseMiJ) chasem(l )- We also write in such case that... 

Like U, the instance U is data exchange equivalent to I with respect to M". (The only difference from U is in the major field, which is not used by the chase with M".) Furthermore, such instance U would be obtained if we use the following inverse instead of... 

Putting it all together, we now formally capture the two desiderata discussed above (data exchange equivalence and homomorphic containment) into the following definition of a relaxed chase-inverse. 

The ion-exchange capacity of the membranes is determined using the standard protocols [36]. Equilibrium data for equivalent ionic fractions of Al " " and in the aqueous phase and the corresponding fraction in the membrane phase are then experimentally determined for a given total ionic concentration Ct expressed in eq/m. Average selectivity value is subsequently generated using Equation 34.14b. 

These two approaches to deriving K and Z from gradient retention data are equivalent. We prefer our approach because the same computer program used for deriving values of 5 and k, from reversed-phase gradient data can be used in similar fiuhion fbr ion exchange. 

EPA has proposed electronic filing regulations and if these go into effect then requests for determinations of equivalency filed after the effective date must be made using the ePMN software, and may be filed on paper, through CD, DVD, or EPA s Central Data Exchange (CDX) for one year after the effective date of the new rules, and thereafter must be submitted via CD, DVD, or CDX for the next year, and then only through CDX. ... 

XML equivalent offers the advantage that XML files can be read and written based oti the XML specifications. The XML-formatted data can then be used, due to the advantages of using XML-formatted information, for data exchange. Open tools can be used to read XML-formatted data since XML is a standard that is well established in current industrial practice. 

This technique constitutes a modified version of the ECR technique encompassing the use of a sinusoidal variation of the O2 partial pressure. Under such conditions, the obtained impedance diagrams can be contrasted with the equivalent circuits showing the best fit to experimental data. This equivalent circuit is interpreted in terms of bulk diffusion and surface exchange reactions. 

Pressure loss in a piping system (not including the tanks, heat exchangers, distillation columns, etc.) is usually expressed in units oi feet of flowing fluid, or the equivalent converted to pounds per square inch. Some published pressure loss data is expressed as per 100 equivalent feet of the size pipe being used or estimated. 

Figure 8. Percentage illite layers versus equivalents of fixed interlayer cations (Na + K) per illite layer [based on 01o(0H)2]. Solid circles = aluminous smectites with 1 Sr-exchange. Open circles = aluminous smectites with 2 or 3 Sr-exchanges. X = iron-rich smectites with 1 Sr-exchange. Points calculated from data in Tables III, IV, VI, and VIII.

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