Amorphous silicon and germanium films for uncooled microbolometers

The possibility of using amorphous silicon and germanium films prepared by magnetron sputtering as components in uncooled microbolometers has been analyzed experimentally and results are presented. Amorphous silicon and germanium films having activation energies of 0.135 and 0.2 eV, and resistivities of 50 and 0.4 kΩ·cm, respectively, were fabricated. Pis’ma Zh. Tekh. Fiz. 23, 21–26 (July 12, 1997)     

A model for standardization of lung function parameters by height

Lung function parameters are closely associated with the height of the individual and this is the reason why this genetically determined characteristic is present obligatorily in the equations giving their reference values. The present work studies a large group of models by analysing two groups of healthy individuals - 20 healthy boys aged 7 to 14 years (10.6 +/- 2.2; mean +/- SD) with a height of 121 to 170 cm (145.0 +/- 14.2) and 98 healthy men aged 30 to 60 years (44.7 +/- 6.7) with a height of 159 to 192 cm (171.0 +/- 9.1), all of them non-smokers. Statistical analysis shows that standardization of lung function parameters by height of healthy individuals is achieved by using a power function of the height - FEV1/2.7 and VC/H2.6 for boys aged 7 to 14 years and FEV1/H2.5 and VC/H2.4 for men aged 30 to 60 years. The model proposed for children practically neutralizes age completely and can be used as a reference equation. The graphic and correlation analysis of the residuals obtained as a difference between the actual and predicted values of the respective models indicated clearly presence of age peculiarities. In men the correlation coefficients between the residuals and the height were close to zero, and the residuals themselves were relatively evenly distributed around the zero line (a homoscedastic distribution). In children the differences scattering increased with the height, i.e. there is a heteroscedastic distribution.     

Rules of plastic deformation and failure of powder metallurgy iron-base dispersion hardened materials

Translated from Poroshkovaya Metallurgiya, No. 6(318), pp. 70–77, June, 1989.     

Convex hull test for ordered categorical data

When testing for stochastic order in ordered 2 x J contingency tables, it is common to select the cutoff required to declare significance so as to ensure that the size of the test is exactly alpha conditionally on the margins. It is valid, however, to use the margins to select not only the cutoff but also the form of the test. Linear rank tests, which are locally most powerful and frequently used in practice, suffer from the drawback that they may have power as low as zero to detect some alternatives of interest when the margins satisfy certain conditions. The Smirnov and convex hull tests are shown, through exact conditional power calculations and simulations, to avoid this drawback. The convex hull test is also admissible and palindromic invariant and minimizes the required significance level to have limiting power of one as the alternative moves away from the null in any direction.