Issue 3

JTAM, Sofia, vol. 9 Issue 3 (1978)

Quantum Mechanics and Quantum Bimolecular Science

G. Brankov
Bulgarian Academy of Sciences; 7 Noemvry Str. Sofia

The present paper is connected with the discussion in the Academy, concerning the modern course of the biological sciences. The view of accelerated development of molecular biology is correct. Yet the starting point of explaining of number of events and processes must be the atomic level as the main point of quantum mechanics. This view was described in the plenary report of the Third National Congress of Theoretical and Applied Mechanics, Varna 1977. Such a view can be applied to a number of biological events and processes, which are explained with the help of quantum biology, quantum biophysics and quantum biochemistry. The necessity of a new scientific course of quantum biomechanics is proved in the paper.

JTAM, Sofia, vol. 9 Issue 3 pp. 013-015 (1978), [Full Article]

Minimax Problems of Control, Observation and Search

F.L. Chernousko, A.A. Melikian
Institute of Problems of Mechanics, Acad. of Sci. of the USSR, Moscow

This paper gives a survey of investigations on minimax (game) problems which were carried out in the Department of Mechanics of Controlled Systems of the Institute of Problems of Mechanics of the USSR Academy of Sciences. The minimax approach, which leads to the realization of a guaranteed value, was applied in these investigations to problems of optimal control with incomplete information about the phase vectors of a system, to problems of optimal multiimpulsive corrections of motion, to problems of differential games with variant conditions of players, and to the devising of optimal algorythms of search for zeros and extrema of functions. The list of references contains all the papers reviewed herein as well as certain articles of other authors, but does not pretend to be complete.

JTAM, Sofia, vol. 9 Issue 3 pp. 016-024 (1978)

Spatial Kinematic Chain Mobility

M.D. Markov
Higher Institute of Mechanical and Electrical Engineering, Sofia

Using screw calculus an analitic criterin is proposed for the evaluation of instantaneous mobility of spatial kinematic chains, while attention is paid to its transitory and in transitory character. In addition gross mobility is defined.

JTAM, Sofia, vol. 9 Issue 3 pp. 025-029 (1978)

On the Stability of Gyrostate Constant Rotation Around the Main Innertial Axis

V.S. Sergeev
Computing Calm Acad. of Sci. of the USRR, Moscow V 333

Permanent rotation stability is analysed with a heavy, one fixed point gyrostate concerned. The above rotation is performed around the main innertial axis. The Arnold – Mozer theorem of two degrees of freedom Hamiltonian system stablity gives a condition of permanent rotation stability, the condition concerning the parameters of the system.

JTAM, Sofia, vol. 9 Issue 3 pp. 030-035 (1978)

Dynamic Creep of Set Polymer

L.M. Hadjikov, K.M. Simeonova
Institute of Mechanics and Biomechanics, Bul. Acad. of Sci., Sofia, Bl. 8, Kv. Geo Milev

An experimental investigation of set polymer dynamic creep is proposed in the paper. The influence of the parameter Paw on the gaining of highly elastic deformation has been determined. Experimental relations concerning the variation of rheology constants, taking part in the Maxwel–Gurevitch–Rabinovitch equation, have been found. Those relations depend on the above mentioned parameter Paw.

JTAM, Sofia, vol. 9 Issue 3 pp. 036-042 (1978)

Finite Integral Transformations in Dynamic Problems Concerning Elastic and Visco-elastic Systems

J.E. Senitsky
Higher Institute of Civil Engineering, Molodogvardeiska 194, Kuibishev, USSR

A method of finite integral transformations in dynamic problems of theory of elasticity and visco-elasticity is proposed in the paper. In this way a special type partial differential equation system is obtained. The example given concerns an elastic round shape plate, loaded by means of distributed nonperiodic load.

JTAM, Sofia, vol. 9 Issue 3 pp. 043-049 (1978)

On the Solution of Jet Theory Boundary Problem

Z.D. Zaprianov, E.L. Majdrakova
Institute of Mechanics and Biomechanics, Bulg. Acad. Sci., Bl. 8, Kv. Geo Milev, Sofia

A solution of a boundary problem, appearing in the process of solving the Glauret problem by means of matching of asymptotic expansions, is given in the paper. The solution is found with the help of the transformation of Dimovsky, which allows the transforming of the condition of vorticity absence, given in cylindric coordinates and concerning the outer region, into a Laplasse equation.

JTAM, Sofia, vol. 9 Issue 3 pp. 050-055 (1978)

Application of the Method of Finite Systems to the Definition of Rod Longitudinal Oscillations

A.I. Baltov, St.M. Todorov
Institute of Mechanics and Biomechanics, Bulg. Acad. Sci., Bl. 8, Kv. Geo Milev, Sofia

The straight rod longitudinal oscillations have been investigated. The rods have been made of different materials – elastic, viscous, plastic. The method of finite systems has been applied to solving the problem. The convergence of the method has been proved. A numerical example has been given, in which a number of comparisons has been made for determining a suitable scheme of discretisation.

JTAM, Sofia, vol. 9 Issue 3 pp. 056-063 (1978)

On the Dynamic Stability of an Elastic Shaft with Nonlinear Boundary Conditions Concerned and Gyrostate Effect Taken into Account

V.A. Alexandrov
Higher Institute of Architecture and Civil Engineering, Hr. Smirnensky Blvd. 1, Sofi

An elastic shaft has been investigated with periodically changing torque applied. The shaft is fixed by means of sliding bearings and existence of lubricating layer, which leads to nonlinear boundary conditions. A numerical example is given, concerning a concrete shaft of a turbo aggregate.

JTAM, Sofia, vol. 9 Issue 3 pp. 064-068 (1978)

On the Definition of Periods and Forms of Eigen Oscillations of Store Building with an Arbitrary Configuration

S. Shishkov
Institute of Technical Cybernetics, Bulg. Acad. Sci., Bl. 4, Kv. Geo Milev

A suitable method for solving the problem is proposed by using the well known method of successive approximations for defining the eigen values and vectors and the system of differential equations of dynamics power method, the latter system describing the oscillations of the proposed buildings. This solution is used in KNIPIOIUS in the process of computing program working out, which concerns the seizmic analysis of multistore buildings, the latter treated as thin wall spatial systems. In the paper results, concerning a 14-store building, designed in IPP "Transproekt", have been demonstrated.

JTAM, Sofia, vol. 9 Issue 3 pp. 069-075 (1978)

Problems and Methods of Theory of Elasticity with Continuous Nonhomogeneous Bodies Concerned

G.B. Koltchin
Polytechnical Institute, P1. Lenin 168, Kishinev, USSR

An analysis of the above problems has been made in the paper, as well as the methods of solving the problems have been discussed.

JTAM, Sofia, vol. 9 Issue 3 pp. 076-079 (1978)