Basic trends in development of drilling equipment for ore mining with block caving method

The authors have determined the causes of drop in performance of induced block caving using fans of blastholes 105 mm in diameter and single blastholes 250 mm in diameter, as well as the sources of increased drilling cost and expansion of start-up time of production blocks in Abakan underground mine. Alternatives of improvement in drilling efficiency under current conditions are discussed.     

Properties of gasars-metallic materials with pores formed by released hydrogen

We developed a new type of porous materials with anisotropic structure based on a large number of metals. It is shown that these material, called gasars, have properties different from the properties of the other porous materials. Thus, the strength of gasars is much higher than the strength of powder materials with the same porosity and their impact toughness is readily regulated by the sizes of the pores. The internal structures of gasars and possible versions of the types of pores in these materials are strongly diversified, which makes the spectrum of their possible applications very wide. We discuss some specific directions of the potential applications of gasars. The results of measurements of the thermal conductivity of gasars and monolithic specimens are presented. It is shown that, for a certain level of porosity, the specific thermal conductivity of gasars is higher than for monolithic materials. We also make some basic conclusions concerning the characteristics of new porous materials. __________ Translated from Fizyko-Khimichna Mekhanika Materialiv, Vol. 43, No. 5, pp. 125–127, September–October, 2007.     

Physicomechanical testing of granular materials

Translated from Khimicheskoe i Neftyanoe Mashinostroenie, No. 1, p. 32, January, 1992.     

Accumulation of hydrogen and its influence on the microstructure and mechanical properties of Kh18N10T steel

By the methods of thermal-desorption spectrometry and nuclear reactions, we study the processes of trapping, thermal desorption, and evolution of the profiles of distribution of deuterium ionically implanted with an energy of 12 keV into Kh18N10T steel at room temperature. The evolution of the microstructure of steel under the conditions of irradiation of samples with D₂⁺ ions up to doses of 1 · 10¹⁸ D/m²−2 · 10²² D/m² is studied by the method of electron microscopy. The regularities of changes in the mechanical properties of steel after irradiation are determined. __________ Translated from Fizyko-Khimichna Mekhanika Materialiv, Vol. 43, No. 5, pp. 117–121, September–October, 2007.     

Inverted structure — A relational model for data identification

The inverted structure is proposed as a relational model of the information kernel in diagnostic and expert systems. The inverted structure can be used for identification of stored data by collections of attributes. The properties of the join operation on partially defined relations and issues of semantic integrity of data are discussed.Translated from Kibernetika i Sistemnyi Analiz, No. 3, pp. 144–164, May–June 1992.     

Automatic recognition fingerspelling gestures in multiple languages for a communication interface for the disabled

This paper presents the design and evaluation of a multi-lingual fingerspelling recognition module that is designed for an information terminal. Through the use of multimodal input and output methods, the information terminal acts as a communication medium between deaf and blind people. The system converts fingerspelled words to speech and vice versa using fingerspelling recognition, fingerspelling synthesis, speech recognition and speech synthesis in Czech, Russian, and Turkish languages. We describe an adaptive skin color based fingersign recognition system with a close to real-time performance and present recognition results on 88 different letters signed by five different signers, using above four hours of training and test videos.     

Orientational crystallization and orientational drawing as strengthening methods for polyethylene

This paper reports on the theoretical and experimental studies of structure formation and strengthening (stiffening) of flexible-chain polymers. Two techniques of strengthening relying on the melt extrusion, i.e., orientational crystallization (crystallization initiated by melt extension) and drawing (uniaxial stretching of a crystallized polymer) are analysed by theory. The experiments involved preparation and study of melt extruded films and film fibers of linear polyethylene formed by the two techniques mentioned above. The effect of the degree of orientation and other parameters of the formation processes on the mechanical characteristics and the factors limiting the ultimate values of these characteristics are discussed. It is shown that multistage drawing succeeds in achieving a higher tensile strength and elastic modulus (1.2 and 35 GPa, respectively) than the orientational crystallization, which gives 0.8 and 15 GPa. The strengthening by drawing is accompanied by microcrack formation. In contrast, no discontinuities are observed in orientationally crystallized samples up to their ultimate extension.     

Facilities for calibration of dc emf measures and voltmeters

A set of instruments for reproduction and storage of the emf and dc voltage unit and for transferring it directly to the location where measuring instruments (MIs) are used with an accuracy of (3–5) ·10^–7, developed at the VNIIFTRI Research and Production Association (RPA) is described. The metrological characteristics of the set are investigated.Translated from Izmeritel'naya Tekhnika, No. 1, pp. 63–64, January, 1994.