Solving problems of using some nonparametric goodness-of-fit tests

Estimates are given of the power of the Kuiper and Watson goodness-of-fit tests and three Zhang tests with the Z _A , Z _C , and Z _K statistics with respect to some pairs of competing laws in testing simple and composite hypotheses. The powers of these tests are compared with the powers of the Kolmogorov, Cramer-von Mises-Smirnov, and Anderson-Darling tests. Statistic distribution models and tables of percentage points are constructed which allow the Kuiper and Watson goodness-of-fit tests to be used to test composite hypotheses about the goodness of fit of samples against various parametric distribution laws. An interactive simulation method is proposed that allows constructing and using distributions of test statistics in solving problems of statistical analysis.     

Peculiarities of measurements in scanning electrical-conductivity microscopy

Functional capabilities of the scanning electrical-conductivity microscopy (SECM) in determining the electrical conductivity of nano-sized elements, studying the nanostructure of conductive coating materials, and evaluating the conductivity of nano-objects are described. The applicability of the SECM to finding imperfections in the multilevel metallization of integrated circuits with a nano-sized topology is demonstrated.     

Application and power of criteria for testing the homogeneity of variances. Part II. Nonparametric criteria

The distributions and power of nonparametric tests of the homogeneity of dispersion characteristics (Ansari–Bradley, Mood, Siegel–Tukey, Capon, and Klotz) are studied. A comparative analysis is made of their power relative to the classical tests for the homogeneity of variance (Fisher, Bartlett, Cochran, Hartley, Levene). Tables of percentage points for the Cochran test are given for non-normal distributions.     

A Gas Generator Based on Porous Titanium in the Composition of Sealed-Off Plasma Focus Chambers

Instruments and Experimental Techniques - The use of a gas absorber based on porous titanium as a gas generator as part of a sealed electrovacuum device, that is, a plasma focus chamber, is...     

Features of “dry” pressing of oxide magnets in a high-gradient magnetic field

Translated from Poroshkovaya Metallurgiya, No. 1(325), pp. 29–31, January, 1990.     

A small triggered high-current vacuum switch

The results of studies of the switching characteristics of small triggered PBY-27C and PBY-27Π vacuum switches with systems of rod and disk electrodes, respectively, are presented. The studies were performed during switching of pulse currents with amplitudes of up to 200 kA at a current-rise rate no higher than 2 × 10¹¹ A/s.