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| ===T-H Example===
| | #REDIRECT [[T-H_Example]] |
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| The following data were collected after testing twelve electronic devices at different temperature and humidity conditions:
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| [[Image:ex1chp9.png|center|300px|]]
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| Using ALTA, the following results were obtained:
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| ::<math>\begin{align}
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| \widehat{\beta }=\ & 5.874395 \\
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| & & \\
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| \widehat{A}=\ & 0.000060 \\
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| & & \\
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| \widehat{b}=\ & 0.280599 \\
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| & & \\
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| \widehat{\phi}=\ & 5630.329851
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| \end{align}</math>
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| A probability plot for the entered data is shown next.
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| [[Image:ALTA9probabilityplot.gif|center|550px|Probability plots at the tested combinations.]]
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| Note that three lines are plotted because there are three combinations of stresses, namely, (398K, 0.4), (378K, 0.8) and (378K, 0.4).
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| Given the use stress levels, time estimates can be obtained for specified probability. A Life vs. Stress plot can be obtained if one of the stresses is kept constant. For example, the following picture is a Life vs. Temperature plot at a constant humidity of 0.4.
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| [[Image:ALTA9stressplot.gif|center|550px|Life vs. Temperature plot with humidity fixed at 0.4.]]
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