A method for raising the accuracy of frequency measurement

A method is considered for making high-precision frequency measurements with simple, inexpensive, and inexact frequency meters.Translated from Izmeritel'naya Tekhnika, No. 10, pp. 53–54, October, 1993.     

Rapid isothermal processing of Pt/Ti contacts to p-type III-Vbinary and related ternary materials

Results of an extensive study of the interfacial intermixing and interaction of the Pt/Ti bilayer metallization to seven III-V binary and related ternary compound semiconductor systems, as well as the contact electrical properties, are given. Pt/Ti contact to InAs and In_0.53 Ga_0.47As were ohmic as deposited, while the same metallization scheme on GaAs, GaP, InP, In_0.52Al_0.48 As, and Ga_0.7Al_0.3As provided a rectifying contact as-deposited. The latter group of contacts, with the exception of InP and GaP, were transformed to an ohmic contact as a result of rapid thermal processing (RTP) at the temperature range of 300 to 450°C. A linear correlation between the semiconductor bandgap value and the Schottky-barrier height, measured in the Pt/Ti contacts, was observed     

Delayed coincidence measurement of γ-ray time distribution in wood

The results of measurements on time distribution and energy spectrum of -rays from an instantaneous point source in a uniform wood medium are described. Delayed coincidence technique and the Co⁶⁰ -pair were used for the measurements. For an average -ray energy of 0.8 Mev, the half-width of the time distribution was about 7 nsec at 200 cm from the source. An intensity build-up factor of 10.4 was obtained from calculations based on the measurements.The authors consider it a pleasure to thank Ya, B. Zel'dovich, Yu. S. Zamyatnin, and V. G. Morozov discussion of the results and for many valuable suggestions.     

Heuristic Optimization Methods for Dynamic Panel Data Model Selection: Application on the Russian Innovative Performance

Innovations, be they radical new products or technology improvements, are widely recognized as a key factor of economic growth. To identify the factors triggering innovative activities is a main concern for economic theory and empirical analysis. As the number of hypotheses is large, the process of model selection becomes a crucial part of the empirical implementation. The problem is complicated by unobserved heterogeneity and possible endogeneity of regressors. A new efficient solution to this problem is suggested, applying optimization heuristics, which exploits the inherent discrete nature of the model selection problem. The method is applied to Russian regional data within the framework of a log-linear dynamic panel data model. To illustrate the performance of the method, we also report the results of Monte-Carlo simulations.     

Complex automation of aerodynamic experiment in T-106 transonic wind tunnel

The system of complex automation of aerodynamic experiment in T-106 TsAGI transonic wind tunnel is presented. Data acquisition processes, as well as control processes for the model’s Mach number and angle of attack are automated on the basis of new data acquisition and control system involving IVK M2 data acquisition software package and VMIC control software package. The results of balance and pressure experiments (and of the combined ones) are presented. Stages of experimental results processing are described.     

Design and manufacturing of X-band RF MEMS switches

Microsystem Technologies - In this article, we present the results of the design of different geometries for X-band RF MEMS switches. A number of mechanical and RF optimizations are described along...     

Achievements in the synthesis of thiophene-containing polymers

The recent trends in the synthesis, characterization, and application of thiophene-containing polymers are surveyed. This review covers methods used for the synthesis of polythiophene and thiophene-based copolymers via oxidative dehydropolycondensation as well as electrochemical and metal-catalyzed polycondensations. The synthesis of polythiophenes carrying bridge groups annelated by aromatic rings is also discussed. The data on macromolecular transformations occurring during the synthesis of polythiophene, as well as on hyperbranched, macrocyclic, and organoelement thiophene-containing polymers, are summarized.