Testing technologies test frequency

The results of both experiments showed that the analysis in the frequency domain provides new technological possibilities of testing characteristics of austenitic steels. Using known phase-frequency characteristics of structural noises it is possible to construct algorithms for separation of useful signal from the defect, even through amplitude values of noise and signal are close in value. 

Maser amplifiers are used where the requirement for a very low noise amplifier outweighs the technological problems of cooling 10 low temperatures. They have been used in passive and active radiostronomical work, in satellite communications, and us preamplifiers for microwave spectrometry The ammonia and the atomic hydrogen masers have been studied as frequency standards and have heen used in accurate tests of special relativity. 

A minimum interval of three months between tests of each critical instrument loop is recommended in no case should the interval exceed 12 months. However, frequency of testing should be based on plant judgment and experience, as well as on Technology Center information. 

Dynamic-mechanical testing of cross-linked samples are often carried out with high precision on specimen strips in torsion mode, e.g., with a Rheo-metrics Dynamic Analyzer II (RDA) with a sample size of 28x10x2 mm. Here, temperature-and strain sweeps are performed in a displacement range from 0.01% to about 5% strain and a frequency range between 0.1 and 100 Hz. Dynamic mechanical testing of uncross-linked samples can be made, e.g., with a Rubber Process Analyzer RPA 2000 (Alpha Technologies) from 0.28% to 350% strain at various frequencies and elevated temperatures. 

In collaboration with Mieczkowski and associates, we have performed extensive epidemiological studies of drug use in arrestee populations in Pinellas County, Florida. The studies, by comparing hair, urine, and self-reports, also provided independent validation of our hair analysis technology. In addition, these studies provided further evidence for the absence of racial bias in hair testing, a correlation between frequency of cocaine use and cocaine levels in hair, and information on the relative effectiveness of hair and urine analysis for identifying drug use. 

When the Test for Sterility was first published in the 1930s, it was, at best, being done in glove boxes. The pharmacopeias recognized the probability of incidental contamination and permitted, in the event of Test failure, an automatic right to retest without further ado. However, with the advent of HEPA filtration and laminar flow technology in the 1960s, the actual frequency... 

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