The current work considers the problem of arrangement optimization of non-convex polyhedrons into a minimal height parallelepiped container. The no-fit polyhedron based algorithm is proposed to solve described task. The no-fit polyhedrons are used not only for providing conditions of the polyhedrons mutual non-intersection but also for finding the placement points. The current paper provides the block diagrams and the pseudo code of the algorithm. Some examples and computational results are also given for public input data.
Keywords: packing, no-fit polyhedron, non-intersection, optimization, arrangement
Currently most used energy absorbers can be represented classic spring-damper scheme in which the binding is the presence of the elastic work item and damper. Applied to seysmoudarnomu works best security systems installations are systems that do not have elastic elements. For hard metals, which are material for the work items absorber characterized by the appearance of a tooth during the deformation strength. For the calculation of the power characteristics of the work item should be modeled phenomenon associated with the formation of the yield drop. Modeling of the phenomenon of this article.
Keywords: Dynamic loading, uprugoplastichesky deformation, deformation chart, power absorption, tooth strength
Currently actively promote seismic associated with the use of special devices, so-called energopoglotiteley. This paper shows that the design energopoglotiteley advisable to make so that the work item had torsional strain. These EPA bdut have maximum energy absorption with minimal weight. Designs of EPA.
Keywords: Dynamic loading, uprugoplastichesky deformation, deformation chart, power absorption
Currently actively promote seismic associated with the use of special devices, so-called energopoglotiteley. Are very effective konstrutsii energopoglotiteley in which the working element undergoes torsional strain. These EPA have the maximum energy absorption with minimal weight.
Keywords: Earthquake protection, energy absorption, the diagram of deformation, plastic deformation, plastic torsion
In this article is considered the status and problems of timber industry of USSR during the period of perestroika (1985-1990), the period which became a kind of alternative to the Soviet economies development and, in particular, in timber industry. Special attention is paid to the development of forest machinery, as a factor that restrained the realization of potential of native scientists, engineers and producers. The result was realized in ever-increasing backlog of home machinery from abroad. This backlog caused further irreparable blow to the Onezjskji and Altaiskij factories in post-perestroika years, when loggers began to prefer foreign machines for logging operations, created mainly by firms from Scandinavian countries, which pursued an aggressing marketing policy.
Keywords: historical experience, forest sector, mechanical engineering, perestroika, innovative development.
Information about authors of issue №2 (2012)
The results of studies of the effect of complex polyfunctional additives consisting of superplasticizer stabilizer and redispersible powder on strength and shrinkage of cement paste.
Multiplicative model is developed, with which is possible to regulate the formation and development of deformation strength compositions for various compositions of dry building mixes. Dependencies describing the influence of the complex polymer additives on the formation and development of the deformation strength of cement stone. The functions of the coefficient values depending on the dosage used additives.
Keywords: dry mortar, cement stone, additives, modifiers, superplasticizer additive stabilizing effect, redispersible polymer powders, strength, shrinkage deformation.
Information about authors of issue №4 (2008)