Identification Examples

Two identification examples will be discussed in this section. The parametric model identification is done in MATEAB using the identification toolbox. Let us assume that you have copied the files on your distribution disk to the directory C MatlabR14 work directory. Start Matlab by double clicking the Matlab icon. You are now ready to run the identification examples. 

In this section the design of three different parametric models, an ARX model, an ARMAX model and an OE type model, will be discussed on the basis of the process data provided in p 11. mat. First it will be demonstrated how code can be written to carry out the identification exercises, subsequently the use of the MATLAB ident toolbox will be demonstrated. 

1 Model Identification for a Process with One Input and One Output 

The ARX model has the general format as shown in Eqn. (24.3).Using least squares error minimization, the following result is found  

The model residuals can be calculated and the autocorrelation and cross correlation of the residuals with the input are calculated and shown in Fig. 24.5. 

---

Fio. 13, Comparison of model predictions (solid line) with training data (dashed line) for identification example. 

An analysis strategy can generally be outlined in three steps (1) Sample preparation, (2) Screening and Analysis, and (3) Data evaluation and identification examples are described in the following sections. 

Analytical TLC differs from PLC in that larger weights and volumes of samples are applied as a band across the entire layer width to thicker (0.5-2 mm) and sometimes larger layers, the purpose of which is the isolation and purification of 10-1000 mg of sample for further analysis. Multiple development of the plate is commonly used, and the separated substances are detected by a non-destructive method (e.g., under UV light and iodine vapors), and recovered by extraction from scraped layer material. PLC can be used to isolate sufficient pure drug compounds for confirmation by spectrometry in cases where analytical TLC is not adequate for identification. Examples of pharmaceutical applications of PLC include a new sesquiterpene trimer and phenylpropanoid glycosides. ... 

Example 23.1 Model Identification Example 23.2 Models to Propose Experiments... 

Often bacteria remain together in specific arrangements after cell division. These arrangements are usually characteristic of different organisms and can be used as part of a preliminary identification. Examples of such cellular arrangements include chains of rods or cocci, paired cells (diplococci), tetrads and clusters. 

Identify bond clashes as minus-minus or plus-plus connections between adjacent atoms and atom clashes as dual minus and plus designations for the same atom. The more clashes there are, the more difficult it is to synthesize the molecule. Color code these clashes with gray bonds for easy identification. Examples of bond and atom clashes are given in the following. 

Conversely, one can have non-isostmctural or non-isovalent alloys. Note, however, that because compounds with different structures or valences do not readily dissolve in each other, these latter categories are rare and must be produced by nonequilibrium processes such as sputter deposition (see Chapter 11). All commonly used alloys are both isostructural and isovalent, therefore this is not a very useful description. Henceforth, we will stick to the pseudobinary,. .. identification. Examples of non-isovalent and non-isostructural alloys are considered in Section 6.5. 

---