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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.gif|thumb|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|thumb|center|300px|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. Humidity plot at a constant temperature of 338K.
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| [[Image:ALTA9stressplot.gif|thumb|center|300px|Life vs. Humidity plot with temperature fixed at 338K.]]
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