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The influence of initial geometric imperfections in the shapes of eigenmodes and periodic modes on the load-carrying capacity of a steel stringer-stiffened cylindrical shell subject to axial compression is studied. For comparison of the influence of different shapes, the imperfections are normalized by an integral-energy measure, which is considered as an alternative to the commonly applied amplitude. The shell dimensions are chosen out of the set of 24 small-scale specimens tested between 1981 and 1984 at Imperial College in London. Published results of statistical analysis of measured imperfection surfaces of the set are employed for checking their conjectured relationship to the normalization of imperfections by the energy measure. The study is finite element method (FEM)-oriented; the numerical model is checked by application of two FEM codes.

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Modulus of elasticity of steel wire rope (elastic modulus) is a characteristic value, which is important not only for users of the steel rope, but also for designers of machines and machinery that are equipped with the steel wire rope. Values of the elastic modulus depends predominately on the elastic modulus of the material, which the rope is manufactured from as well as it depends on the various other factors. The most important influencing factors are as follows: rope construction, type of core, angle and way of wire stranding, angle and way of rope lay as well as kind of lubricant. The real value of the elastic modulus has also impact on prolongation of the steel wire rope and on intensity of its dynamical loading. The rope elastic modulus value can be determined by means of the various methods. There are analysed in this article such methods for determination of the rope elastic modulus, which can be applied for a computer simulation.

In the paper the principle of welding simulation is presented and the methods of solution of phase transformation are described. The first part characterizes elementary equations of heat transient solution, boundary conditions during welding simulation (prescribing moving heat flux, convection, radiation). The methods of phase transformations’ solution are described for diffusion processes as well as diffusionless processes.

The paper deals with the minimachine designed to move within the pipes with inner diameter less than 25 mm. The minimachine consists of two modules connected by a link of variable length enabling to change their mutual distance. Motion is based on inchworm principle known from biology. In motion sequence one of the modules is anchored to the inner surface of the pipe, while the second is released and moved forward by change of the link length. The principle of the link length change consists in transformation of the actuator rotary movement to the linear motion. Problem of anchoring the modules by flexible metal bristles is analyzed in the paper. INTRODUCTIONNowadays the mobile machines for motion within pipes represent a promising area of Vladimír IVANČO (SK)