Category indicators

Selection of impact categories, category indicators, and models... 

Calculating the magnitude of category indicators relative to reference value(s) (Normalization)... 

The sum of indicator values obtained when multiplying all emissions assigned to that impact category by their respective characterization factors is called the category indicator result. The indicator moles of may, for instance, be the sum of contributions from sulfur dioxide, nitrogen oxides, and hydrogen chloride, and there is a characterization factor for each of them relative to the indicator. 

The category indicator results may then be analyzed further by norrnaliza tion, grouping, and weighting. 7 hese procedures are optional in the standard, as they are not as well known as the preceding steps and they contain more subjective elements. The aim of these steps is to clarify the results by comparing them to some reference. 

ISO 14042 defines normalization as calculation of the magnitude of indicator results relative to reference information . The main aim of normalizing the category indicator results is to better understand the relative importance and magnitude of these results for each product system under study. For the purpose of normalization in LCA, Wegener Sleeswijk et al. [13] have made a comprehensive inventory of extractions and emissions of substances for the world level in the year 2000. The normalization in this project is based on these reference emissions and extractions. As a result the normalized score of an impact category for the cushion vinyl floor covering case is expressed as a fraction of the world problem. 

A number of PLS variants have been deployed, for instance, for developing nonlinear models and for predicting together several response variables (PLS-2). Furthermore, when category indices are taken as response variables, PLS may work as a classification method which is usually called PLS discriminant analysis (PLS-DA). 

German chamomile is listed by the Council of Europe as a natural source of food flavoring (category N2). This category indicates that chamomile can be added to foodstuffs in small quantities, with the possible limitation of an active principle (as yet unspecified) in the final product. German chamomile is commonly used in herbal teas. 

For every impact category the proper category indicator is calculated. 

With the inventory tables (Table 18.5) drawn up in the previous phase of LCA in mind, it is time to move on to the next step, which is called characterization. The results of this step are presented in a graph showing a number of impact category indicator results calculated from the LCI results. It is an obligatory step in impact assessment. In this example, we use the... 

Each bar (column) represents the impacts arising from different subassemblies of the analytical protocol studied. With all impact category indicator results scaled to 100%, it is not easy to see which parts of the assembly have the highest overall environmental impact. Each bar on the histogram could represent 100% of a very large impact, or, equally, 100% of a small one. To obtain a better picture, the normalization procedure is used (Figure 18.6). 

Enzymes are placed in various major categories indicated by the first number of the EC number, namely (reaction catalysed in parentheses) (a) oxidoreductases (oxidation-reduction reactions) (b) transferases (transfer of chemical groups e.g. phosphoryl transfer) (c) hydrolases (hydrolysis or cleavage of bonds involving reaction with H20) (d) lyases (cleavage of C-C, C-O and C-N bonds and often yielding a double bond) (e) isomerases... 

Drug" Category Indication Commercial Names Strength(s) Available (%)... 

Does the spread of data points for a particular severity category indicate major differences between species or are the results from different species congruent ... 

Reactions of carboxylic acids can be grouped into the four categories indicated in Figure 20.4. Of the four, we ve already discussed the acidic behavior of carboxylic acids in Sections 20.3-20.5, and we ll discuss reduction in the next section. The remaining two categories are examples of fundamen-... 

Some category indicators can be further cross-aggregated and compared on a natural science basis. Further aggregation can be to calculate the overall sum of years of human life lost, for example, the years of life lost that are attributable to climate change, potential carcinogenic effects, noise, traffic accidents, etc. 

Calculation of impact category indicators using characterisation factors (characterisation). 

A medication pregnancy category indicates the medication s effect on a fetus and how safe the medication is to administer to a pregnant woman. 

Cocaine is listed as a Schedule II drug. This means that it is considered to have a high potential for abuse, and that abuse of cocaine may lead to severe psychological or physical dependence. However, its placement in this category indicates that it has a currently accepted medical use in treatment in the United States or a currently accepted medical use with severe restrictions. ... 

Generic Name Chemical Name Brand Name(s) Drug Category Indication... 

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