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The paper models the mechanical behavior of the human cornea affected by intraocular pressure and external effects. It reviews publications on the development of mathematical models of the cornea and some approaches to studying its mechanical behavior. A finite element model of the cornea is proposed, which allows the stress-strain state in the cornea to be determined from solving the boundary value problem of the theory of elasticity. Test calculations are shown. The model can be used, particularly, for studying the strain of the cornea resulting from surgery. [ABSTRACT FROM AUTHOR]

Software for calculating the energy and force parameters of metal extrusion (SCPPME) is presented. It allows various processes of metal extrusion to be studied. The structure of the program and the program modules is described. As an example of program application, the average temperature of a titanium billet in the extrusion process is determined. The calculation uses experimental data obtained from the extrusion of titanium alloy pipes and bars. The software has great potential for studying various extrusion processes. It can be used both by students for educational purposes and by technologists at metallurgical enterprises. [ABSTRACT FROM AUTHOR]

The paper develops a mathematical model describing the behavior of the human cornea affected by intraocular pressure and external factors. The relevance of the study stems, particularly, from the urgent ophthalmological problems of hyperopia treatment. An effective remedy for hyperopia treatment is laser vision correction consisting in cornea deformation. The mathematical model enables the condition of the cornea after surgery to be estimated. The proposed model is based on the calculation of the cornea stress-strain state via the solution of a boundary value problem of elastostatics. [ABSTRACT FROM AUTHOR]

The aim of the study is to determine the strain state of a briquette during the compacting process. Modeling is performed with the use of a software system for the compaction process. Gurson’s yield condition for a plastically compressible continuum is applied. A comparison of the known experimental data is made, and it shows good qualitative convergence results. [ABSTRACT FROM AUTHOR]

The paper reports on the results of briquetting coke breeze with a binder in a closed cylindrical press-die. Liquid glass is used as a binder. Approximating curves for the "compaction ratio vs. compaction pressure" dependences are plotted from experimental data. The mechanical properties of the briquettes are determined, namely, drop damage resistance and breaking stress. The results are presented as approximating dependences in the form of a power function. [ABSTRACT FROM AUTHOR]

The paper deals with the development of algorithms for solving nonlinear problems of heat conduction in bodies consisting of layered metal composites. The nonlinearity of the problems is governed by the temperature dependence of the heat conductivity coefficients of the composite layer materials. Mathematical models and solution algorithms based on the boundary element method have been constructed for one-dimensional cases of heat distribution. [ABSTRACT FROM AUTHOR]

Drop damage resistance is experimentally found and breaking stress is determined in radial compression tests for green and dry chrome concentrate briquettes. The paper studies the influence of compaction pressure and the amount of the binder on compactibility in the testing of cylindrical briquettes. The aim of the study is to determine optimal briquetting process conditions for the production of high-quality metallurgical briquettes by roll briquetting. [ABSTRACT FROM AUTHOR]

The process of multi-pass wire drawing is considered. A mathematical model of the wire drawing process is developed with the use of the CAE package. Simulation results are presented for 4 passes of drawing. Strain state is defined for all the passes of wire drawing. [ABSTRACT FROM AUTHOR]

The shape and chemical composition of particles polluting the surface of ultrafine wire made of the platinum Pt92.5Pd4Rh3.5 alloy has been revealed by electron microscopy and microspectral analysis. The phenomenon of the appearance of pores in the particles, which are elongated in the direction of drawing, has been discovered. The problem of calculating the stress-strain state is stated by the finite element method. After solving the problem, it is demonstrated that the appearance of additional defects is related to the proportion of stresses in the scheme of metal forming by drawing. [ABSTRACT FROM AUTHOR]

The paper studies the effect of compaction pressure and the amount of a plasticizer on the compactibility of molybdenum powder in the manufacture of cylindrical briquettes. The coefficients of the regression equation for the compactibility curves of molybdenum are determined. [ABSTRACT FROM AUTHOR]