Performance degradation simulation of electronic product for reliability analysis
To study analysis method of performance degradation during long term operation based on function simulation, accelerated degradation test was carried out on the power supply module directly, and the test data was used for reliability analysis. As the same time, accelerated degradation test was carried out on the key components in power supply circuit. The test data was injected into the functional simulation model of power supply to simulate performance degradation and analyze reliability. Finally the results of the two kinds of analysis were compared to demonstrate the effectiveness of the proposed simulation method. Comparison shows that average life span of power supply is 281560 hours based on accelerated degradation test while 357290 hours based on degradation simulation. Since only considering degradation of the key components, the result of simulation method is of partial optimism. But the deviation is in a reasonable range, which proved that the method is effective.
Research on reliability assessment of metalized film capacitors based on T performance degradation test
Metalized film capacitor is a kind of product with a long lifetime and high reliability, so it is difficult to assess its lifetime and reliability using the traditional statistical inference based on the large sample of data from the lifetime test. Therefore, first, this paper presents a type of test called T performance degradation test, which is divided into several stages. During the test, the number of capacitors which are still under working conditions decreases stage by stage until the test lasts a long time with very fewer capacitors. Finally, this paper presents a reliability assessment method based on the data from the test. At last, an application on the reliability assessment of the energy system of the laser facility is presented.
Enumeration of total coliforms, fecal coliforms, and Escherichia coli in foods by hydrophobic grid membrane filter: supplementary report.
Raw, comminuted poultry meat was used to determine the specificity of the media and incubation conditions used in the hydrophobic grid membrane filter method. Confirmation rates for target colonies were 100% for total coliforms, 98% for fecal coliforms, and 97-99% for Escherichia coli. The results of total coliform enumeration in 30 pasteurized milk samples by both the hydrophobic grid membrane filter method and AOAC method 46.013-46.016 are also reported.