task have been found to concentrate longer and per- form with a higher degree of accuracy than those with less experience. Most of these benefits, however, were found in search tasks that have a controlled amount of variation, unlike typical cast- ing surface inspection tasks. General intellectual aptitude is another known factor in determining the capabilities of a visual inspector. As one would expect, higher intellectual apti- tude correlates positively with higher levels of visual inspection success. Tis appears to be due to an increased ability to adapt strategies and utilize memory techniques that aid in the visual inspec- tion process. Te cognitive inspection style of individuals also appears to be a factor in visual inspection capabil- ity. Specifically, the Matching Familiar Figures Test (MFFT) has been shown to have potential in determining
As time on task increases, participants tend to lean forward, change postures more frequently, report more discomfort and take more time performing visual inspection. Another task factor is
Fig 1. Shown is an example of the Matching Familiar Figures Test (MFFT).
individual potential in performing visual inspection tasks. Task factors: Te task itself can
greatly affect an operator’s abil- ity to perform a visual inspection. Depending on the kind of visual inspection being performed, posture and physical strain can impact visual inspection capabilities negatively. Several authors have shown select visual inspection jobs suffer from decline in visual inspection perfor- mance as a result of physical strain.
the level of documenta- tion provided for on-the- job comparisons. It is much easier to perform a relative judgment than
it is to make an absolute one. It can be very beneficial to provide aids, such as comparator plates that allow visual inspectors to compare a possi- ble flaw to a known category of flaw. Several studies have shown visual inspectors that are given an effective comparison aid consistently outper- form those forced to make absolute judgments alone. Terefore, simply giving the visual inspector a visual reference aid can greatly increase his or her basic capabilities.
42 | MODERN CASTING January 2014
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