General Selection Criteria

The above has been an attempt to discuss some of the requirements that must be taken into consideration when selecting the best suited agglomeration method for a particular project. Of course, this treatment of the subject is not complete and a new set of conditions must be developed for each application. It should be accepted as a rough guideline directing the investigator to the most important parameters to be considered. 

To fully appreciate the information supplied in Table 8, it must be understood that not only the particular piece of equipment is rated but also the entire system. For example, the power requirement and investment cost of a disc or drum is much lower than that of a roller press with comparable throughput however, if the entire system is investigated, in most cases the relationship is reversed. 

In conclusion, the list must be used prudently by also taking into consideration the special conditions of a given project and common sense. 

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Where retained strength data is unavailable, weight loss and, if possible, volume change affects should be used as general selection criteria. 

Approaches to the selection of an extractive distillation solvent are discussed by Beig," Ewell et al.,z and Tassios.20 In general, selection criteria follow those for azeotropic enirainers ... 

Table 15.2 shows the microbial species commonly added as starter cultures, as well as their effects. General selection criteria include ... 

Selecting the proper solvent by considering this criterion is still based on empirical approaches because of the large nonideality of the resulting mixtures. However, general selection patterns and rapid experimental techniques have been made available through the years. This paper presents a review of some of these methods to facilitate the solvent selection process in the chemical industry. Qualitative aspects are first considered, followed by empirical correlations and rapid experimental techniques. 

Peirce considers that each effective selection-criterion is a general rather than a particular (a universal rather than a substance). Each such criterion might be... 

Rajkd, R. and H berger, K., Conditional Fisher s exact test as a selection criterion for pair-correlation method. Type I and type II errors. Chemom. Intell. Lab. Syst., 57, 1-14 (2001). H6berger, K. and Rajkd, R., Generalization of pair-correlation method (PCM) for nonpara-metric variable selection. J. Chemom., 16, 436-443 (2002). 

Although their methods were similar, the motivations of the two groups appear to be rather different. Hassan et al. wanted to compare the performance of different diversity metrics, while Agrafiotis was interested in a much more general method that could encode any desirable selection criterion (similarity, predicted activity, cost and availability of starting materials, reaction block design, etc.) and would allow... 

Generally, many different tree structures are possible. Shorter trees are usually preferred since they express simpler classification rules which are easier to understand. The cleverness of the decision tree approach is that information theory is used to select an optimal order of the attributes to produce a shallow tree. It is common to base the attribute selection criterion on entropy. In communication theory, entropy is related to the expected information conveyed by a message. The entropy of a message, I m), depends on the probability of the message. 

From the latter discussion, we can also easily identify the previously mentioned ratio of general selection probabilities (4.82) that can be used alternatively in the acceptance criterion (4.80) ... 

In some cases where the ASME Code woidd not require pressure relief protection, the 1.5 Times Design Pressure Rule is apphcable. This rule is stated as follows Equipment may be considered to be adequately protected against overpressure from certain low-probability situations if the pressure does not exceed 1.5 times design pressure. This criterion has been selected since it generally does not exceed yield stress, and most Ukety would not occur more frequently than a hydrostatic test. Thus, it will protect against the possibility of a catastrophic failure. This rule is applied in special situations which have a low probability of occurrence but which cannot be completely ruled out. 

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