Data handling equipment, trends

Table 4.4. Trends in HPLC and Data Handling Equipment...

These include identification of process equipment and instruments, interpretation of the meaning of their values and trends, navigation through different VDU pages by means of a selection menu, etc. The common feature of these tasks is handling the display system to search and locate relevant process data. In this respect, "classical" ergonomics checklists (see Chapter 4) are very useful in facilitating performance of such tasks. 

Expert systems are easy to program and to understand because they usually resemble instructions in English. The time and cost for developing these systems is relatively small. The primary problem usually turns out to be interpreting the sensors. Because first and second derivatives of sensor data are used to find trends and patterns, noise can be a major problem. The rules allow the controller to adapt to the condition of the material and to the geometry of the part. Expert systems make it relatively easy to change to backup plans when sensor or equipment failures occur. In fact, rule-based systems can be quite general and handle a number of materials with little material specific data. 

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