Evaluation of the stressed-state of a bed based on emission memory effects of rocks in near-well space

Mining Institute, Moscow. Translated from Fiziko-Tekhnicheskie Problemy Razrabotki Poleznykh Iskopaemykh, No. 2, pp. 26–29, March–April, 1991.     

Optimal allocation–consumption problem for a portfolio with an illiquid asset

During financial crises investors manage portfolios with low liquidity, where the paper-value of an asset differs from the price proposed by the buyer. We consider an optimization problem for a portfolio with an illiquid, a risky and a risk-free asset. We work in the Merton's optimal consumption framework with continuous time. The liquid part of the investment is described by a standard Black–Scholes market. The illiquid asset is sold at a random moment with prescribed distribution and generates additional liquid wealth dependent on its paper-value. The investor has a hyperbolic absolute risk aversion also denoted as HARA-type utility function, in particular, the logarithmic utility function as a limit case. We study two different distributions of the liquidation time of the illiquid asset – a classical exponential distribution and a more practically relevant Weibull distribution. Under certain conditions we show the smoothness of the viscosity solution and obtain closed formulae relevant for numerics.     

Determination of the plastic anisotropy or irradiated zircalloy tubes

Moscow Institute of Physical Investigations (MIFI). Translated from Atomnaya Énergiya, Vol. 71, No. 2, pp. 134–138, August, 1991.     

Computer modeling of horizontal-stress control in stone beds

Simulated computer modeling of horizontal-stress control in a stone bed is described using the acousto-emission memory effect of the region around a hole. A principle possibility for control is indicated in the case of the equality of horizontal stresses for both random and anisotropic orientation of initial microcracks. A relationship is obtained between the pressure of the hydraulic transducer for which an increase occurs in the intensity of the emission and the level of the horizontal stress in the mass. Translated from Osnovaniya, Fundamenty i Mekhanika Gruntov, No. 6, pp. 9–12, November–December, 1995.     

Informational bases for the monitoring of geomechanical processes

Conclusions The proposed approach makes it possible to design systems for the monitoring of geomechanical processes in an optimal manner. The computational methods that we have examined exhibit flexibility; this makes it possible to implement the method when various initial data are available.The authors thank Professor and Doctor of Technical Sciences I. V. Baklashov for his consultation and useful advice concerning questions of geomechanics, and Candidates of Technical Sciences V. A. Robsman and A. V. Kolesnikov for their joint experimental study.Translated from Fiziko-Tekhnicheskie Problemy Razrabotki Poleznykh Iskopaemykh, No. 3, pp. 3–11, May–June, 1994.     

Study of uranium solubility in gallium-indium eutectic alloy by emf method

Activity, activity coefficients and solubility of uranium in Ga-In eutectic alloy as well as activity of uranium in U-Ga and U-In alloys were determined between 573 and 1073 K using electromotive force (emf) method.