**¹ ****2****(3****1****), 2008**

**SUMMARIES**

Investigation of a plane RRRRT type five-link hinged mechanism with
two degrees of freedom. **N.
Davitashvili.** “Problems of Mechanics”.

Investigation
of a plane five-link hinged mechanism with two degrees of freedom with four
rotary pairs and with one translational pair (RRRRT) has been conducted. The
positions, velocities and accelerations of output links and their points are
determined. The equation of a trajectory of a center of connection hinge of
connecting rods of the five-link mechanism, when one of two input links
accomplishes rotary motion and another - back-and-forth motion. The highest
order of the equation of a trajectory is determined and the ways of solution of
synthesis problems for mentioned mechanisms according to given trajectory
given. 4 ill. Bibl. 17. Engl.; summ. in Russ.

DISCRETE MODEL
AND CALCULATION METHOD FOR ROPE – ROD STRUCTURES. **D. Pataraia.** “Problems of Mechanics”.

In
this paper the method of simulation and calculation of complex rope – rod
structures, membranes and massive bodies basing on the discrete representation
of rope and rods in the form of the set of point masses, springs and dampers is
given. For its realization the algorithm, which leads a computer model of
object from initial state to equilibrium state, is developed. Then, on the
basis of corresponding geometry of a body, the values of efforts, displacements
and other unknown physical parameters are determined. 10 ill. Bibl. 9. Engl.;
summ. in Russ.

Deployable 48 m span
assault bridge. **E.
Medzmariashvili, M. Sanikidze, V. Gogilashvili, N. Tsignadze, G. Bedukadze, G.
Medzmariashvili.** “Problems of Mechanics”.

In
work are
considered single-span, multiple application, extreme bridges, which
collapsible internal structure meets to conditions of its transportation and
installation on a site. Such bridges are installed on the single transport-
installation carrier - truck, tank or helicopter. It is laid and removed from
surmount obstacle in the shortest term. During its installation and dismantle
people do not leave transport-installation carrier. At the same time in a
structure of the presented bridge, from one side is increased the span from 24
meters up to 48 meters and on the other side, the weight and overall dimensions
of its folded package are left the same as for existing 24 meters span bridges.
18 ill. Bibl. 5. Engl.; summ. in Russ.

THE THERMAL
LOADING AND THE SLIDING DISTANCE OF A
WHEEL/RAIL CONTACT. **G. Tumanishvili, M.
Chelidze, I. Tumanishvili, V. Zviadauri.**
“Problems of Mechanics”.

Friction plays a key role in
deterioration of wheels and rails, in fatigue failure of surfaces, in
derailment, in the energy consumed on movement of a train and in other
operational problems. Premature damageability of rails and wheels, as well as
derailment, represents serious problems of a railway transportation. The overload of operating conditions of
machines, increase of capacities and temperatures strengthens importance of
prevention problem of the specified phenomena. The processes proceeding in a
zone of contact of rails and wheels influence a wide spectrum of the phenomena.
Various aspects of these processes are insufficiently investigated and do not
give directly to an estimation. Our research focuses on the investigation of
sliding distance and thermal loading of wheel/rail contact. 5 ill. Bibl. 4.
Engl.; summ. in Russ.

CALCULATION OF THE INTERFACED THERMODYNAMIC
CYCLES - PARADOX OF EFFICIENCY. **A. Aptsiauri.** “Problems of
Mechanics”.

In the work the original method of interface of
cycles of the thermal pump and the thermal engine is offered. The combination of cycles allows
to receive heat from environment. By thermal calculation quite concrete
theoretical indicators of each process are defined, the thermal balance of
cycles is resulted. It is shown that engine work completely balances mechanical
energy which consumes the thermal pump. The attention to additional, detailed
studying of non-stationary processes of heat accumulation and regeneration is
paid that will allow to draw a definitive conclusion on a reality of such
project. 3 ill. Bibl. 5. Engl.; summ. in Russ.

HEAT TRANSFER
WITH THE FLOW OF CONDUCTING FLUID IN CIRCULAR PIPES WITH FINITE CONDUCTIVITY UNDER UNIFORM TRANSVERSE
MAGNETIC FIELDS.** V. Tsutskiridze, L.
Jikidze. **“Problems of Mechanics”.

The flow of
conducting, viscous fluids in circular pipes under transverse magnetic field is
studied theoretically. The correlation of Hartman’s figure, Poisale’s figure,
Reynold’s figure and conductivity of walls are considered. Bibl. 8. Engl.;
summ. in Russ.

THE
SURFACE LAYERS DESTRUCTION OF FRICTION BRAKE MATERIALS. **N. Meliksetyan.** “Problems of
Mechanics”.

The surface layers
destruction studies results of brake friction materials on rubber, binder and
multifunction resins base have been produced depending on surface friction
temperature. Applying the methods of raster electronic microscopy, X-rays
diffraction, and dilatometer analysis it is established that the mechanism of
high temperature wear destructions of the materials’ surface layers corresponds
to the delaminating mechanism of wear. 4 ill. Bibl. 5. Engl.;
summ. in Russ.

VIBRATION
SICKNESS CAUSED BY A MANUAL MECHANIZED TOOL AND THE MEASURES OF PROTECTION. **M. Dzhikia, A. Neverov, N. Machavariani, G.
Shuradze, S. Metonidze.** “Problems of Mechanics”.

The reasons and symptoms of vibration sickness caused by a manual
mechanized tool are considered. The results of experiment on the study of
transmission of oscillations from the source of vibration to the arm and head
of workers are given, and also the calculation formula of the efficiency of
external vibration protection on a basis of the values of impedances of a hand
tool, hands of a man and external vibration protection. 3 ill. Bibl. 5. Engl.;
summ. in Russ.

HEAT EXCHANGE IN
THE MAGNETIC FIELD. **V. Tsutskiridze.**
“Problems of Mechanics”.

The
heat exchange of steady laminarly moving incompressible electro-conductive
liquid in a channel with isothermal walls formed by parallel plates is
considered. The influence of transverse uniform magnetic field on the heat
exchange with constant flow rate of medium and constant pressure drop is shown.
The essential dependence of the temperature of a fluid flow and heat exchange
Nusselt’s number on the value of external magnetic field and electrical
conductivity of the walls of a channel is revealed. Bibl. 5. Engl.; summ. in
Russ.

DYNAMIC SHEARING
STRESSES IN THE BUTT JOINTS OF EXTERNAL AND INTERNAL LOAD-BEARING WALLS OF A **S. Daveyan.**
“Problems of Mechanics”.

In
the article the developed theory of calculation of dynamic shearing stresses in
the butt joints of load-bearing longitudinal and transverse walls under action
of a sudden horizontal load is given.
The calculation expressions allowing optimizing the parameters of
bearing-structure of large-panel buildings are obtained. 2 ill. Bibl. 2. Engl.;
summ. in Russ.

about the method of calculation of the hoses loaded with
concentrated forces. **Z. Arkania, A. Badzgaradze.** “Problems of
Mechanics”.

Present work deals with the method of calculation of hose in the case
when concentrated forces act on it and inner stream of liquid is considered.
Stretching of the hose in the application points of concentrated forces sharply
changes, which considerably influences on liability of the construction. Change
of hose stretch is caused also by the stream of liquid that flows in the hose.
In the work a method of calculation of enough accurasy is described, where
above factors are taken into consideration. Above mentioned method is realized
in Electric Calculating Machine and it is obtained concrete results. On the
bases of these results corresponding recommendations are done. They must be
considered when projectiong the constructions. 4 ill. Bibl. 3. Engl.;
summ. in Russ.

INVESTIGATIONS
AND DEVELOPMENTS IN THE **T. Churadze, D. Kilasoniya, G. Misabishvili.**
“Problems of Mechanics”.

The
aspects of use of New Austrian method in the building of tunnels in

Synthesis of Control With Beforehand Set
Zero Spectrum in the Stationary Integro-Differential Equation of order n. **F.**** ****Grigoryan. **“Problems
of Mechanics”.

The
one-dimensional control choice problem with the beforehand set zero spectrum in
stationary integro-differential scalar equation of the order n is considered
for the case when the quantity of regular inputs is equal to one. Bibl. 5.
Engl.; summ. in Russ.

DETERMINATION OF
A NEED FOR ROLLING STOCK IN THE PROSPECT.
**Z. Meskhidze, G. Telia, A. Sharvashidze,
K. Gudiashvili. **“Problems of Mechanics”.

In the article we
consider an urgent question of exploitation work of railroads and determination
of required rolling stock in the prospect. Formulas for analytical calculations
and corresponding graphs of dependences are recommended. 9 ill. Bibl. 6. Engl.; summ. in Russ.

THE DEVELOPMENT
OF FUNCTIONAL ABILITIES OF LOCAL DIAGNOSTIC SYSTEM LDS BY MEANS OF A CLASSIFIER
OF RAIL CHAINS.** N. Mukhigulashvili, M.
Papaskiri, B. Elbakidze, T. Rokhvadze, D. Iobidze.** “Problems of Mechanics”.

The functional
abilities of local diagnostic system LDS is analyzed consistently. The
automatic diagnostic system developed for rail chains state completes the
functional abilities of local diagnostic system LDS, which cannot store full
information about the state of rail chains. Built by mathematical model, LDS
system can determine the operational modes of rail chains and the form of
damage in a rail chain by the values of two parameters measured in the end of a
rail chain. 2 ill. Bibl. 7. Engl.; summ. in Russ.

THE METHODS OF
CALCULATION OF DAMAGED AND REINFORCED FASTENINGS OF TUNNELS. **V. Tarkhnishvili, N. Maisuradze. **“Problems
of Mechanics”.

The method of
calculation of damaged and reinforced circular form concrete fastenings is
developed. The implementation of the
received results for non-circular form fastenings is shown. The problem is
resolved by use of the functions of complex variables. 4 ill. Bibl. 5. Engl.;
summ. in Russ.

Numerical
research of the compound cylindrical STRUCTURE, transient wave process. **L. Verulashvili, L.
Balanchivadze, G. Gureshidze. **“Problems of
Mechanics”.

In this paper it is
considered the question of change of a
component of cylindrical shell when the left basis of a shell receives jumping
change in loading by the exponential law. Also it is
considered caused by non-symmetrical dynamic loadings. The three-layered
Samarski difference scheme is plotted. The convergence criterion of the scheme
is restored. The numerical analysis of wave process is lead by algorithm. The
plotted curves clearly indicate on possibility of buckling failure of structure
due longitudinal impact. 4 ill. Bibl. 4. Engl.; summ. in Russ.

ON THE STABLE LOCKING IN TO SYNCHRONISM OF THE **M. Baghdasaryan, S. Muradyan.** “Problems
of Mechanics”.

Conditions of achieving stable
locking in to synchronism of the
electric drive system have been
discussed for improving the starting regimes and preventing the electric drive system from damages which
can be caused by the motor fall from
synchronism due to influence of different
factors. 1 ill. Bibl. 5. Engl.; summ. in Russ.

Elaboration of auromated system for
calculation of optimal modes of milling.** L. Tediashvili.** “Problems of
Mechanics”.

The structural
scheme of parametrical optimization for calculation of modes of milling is
suggested, the means of its implementation are considered. The technique of
parametrical optimization is determined in the article. 1 ill. Bibl. 5. Engl.;
summ. in Russ.