keyword optimization

summary:The paper focuses on the acceleration of the computer optimization of heat radiation intensity on the mould surface. The mould is warmed up by infrared heaters positioned above the mould surface, and in this way artificial leathers in the automotive industry are produced (e.g. for car dashboards). The presented heating model allows us to specify the position of infrared heaters over the mould to obtain approximately even heat radiation intensity on the whole mould surface. In this way we can obtain the uniform material structure of artificial leather. The gradient methods are not suitable to optimize the position of heaters because the minimized function contains many local extremes. Therefore, we used an evolutionary algorithm, specifically the differential evolution algorithm. In this case the optimization procedure needs a lot of operations (especially when the mould volume is large and we use a large number of heaters). A substantial acceleration of the calculation can b...

This article focuses on heat radiation intensity optimization on the surface of a shell metal mould. Such moulds are used in the automotive industry in the artificial leather production (the artificial leather is used, e.g., on car dashboards). The mould is heated by infrared heaters. After the required temperature is attained, the inner mould surface is sprinkled with special PVC powder. The powder melts and after cooling down it forms the artificial leather. A homogeneous temperature field of the mould is a necessary prerequisite for obtaining a uniform colour shade and material structure of the artificial leather. The article includes a description of a mathematical model that allows to calculate the heat radiation intensity on the outer mould surface for each fixed positioning of the infrared heaters. Next, we use this mathematical model to optimize the locations of the heaters to provide approximately the same heat radiation intensity on the whole outer mould surface during the heating process. The heat radiation intensity optimization is a complex task, because the cost function may have many local minima. Therefore, using gradient methods to solve this problem is not suitable. A differential evolution algorithm is applied during the optimization process. Asymptotic convergence of the algorithm is shown. The article contains a practical example including graphical outputs. The calculations were performed by means of Matlab code written by the authors.

The aim of the article is to present the most recent outcomes of investigation into the Menzerath-Altmann law. We have addressed the formula of the law introduced by Gabriel Altmann and we will discuss its limits leading to a formula defined for discrete data. We will also compare the results of the research on the law in Polish syntax while applying the formulae for discrete data and continuous data.

summary:Four formulas of the Menzerath–Altmann law are tested from the point of view of their applicability and suitability. The accuracy of related approximations of measured data is examined by the least square method at first. Then the accuracy of calculated parameters in the formulas under consideration is compared statistically. The influence of neglecting parameter $c$ is investigated as well. Finally, the obtained results are discussed by means of an illustrative example from quantitative linguistics