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With the fall of the Berlin Wall, the enlargement of the European Union (EU) by countries from the former Central and Eastern Europe became possible. Science and education are among the best assets of the accession countries, but the unfettered free market represents an increasing threat to their intellectual capital. Science and education have long been instruments of international cooperation. Now they have a vital role to play in leading Europe towards a new age of enlightenment.

Proper selection of the stability parameter determines the accuracy of dendrite tip kinetics at a single crystal scale. Recently developed sophisticated phase field modelling of a single grain evolution provides evidence that this parameter is not constant during the process. Nevertheless, in the commonly used micro-macroscopic simulations of alloy solidification, it is a common practice to use a constant value of the stability parameter, resulting from the marginal stability theory. This paper aims to address the issue of how this inaccuracy in modelling crystal growth kinetics can influence numerically predicted zones of columnar and equiaxed dendrites and the macro-segregation formation.

Using the original authors’ micro-macroscopic computer simulation model of binary alloy solidification, the calculations have been performed for the Kurz-Giovanola-Trivedi (KGT) crystal growth kinetics with two different values of the stability parameter, and for two different compositions of Al-Cu alloys. The computational model is based on single domain-based formulation of transport equations, which are discretized on control-volume mesh. To identify zones of different grain structures, developing within the two-phase liquid-solid region, an envelope of columnar dendrite tips is tracked on a fixed non-orthogonal, triangular control volume grid. The models of porous and slurry media are used, along with the concept of the switching function, to account for diverse flow resistances in the columnar and equiaxed crystal zones. The numerical predictions are carefully studied to address the question of how the chosen stability parameter influences macroscopic structures of a cast, the most important issue from the engineering point of view.

The carried-out comprehensive numerical analysis shows that the value of the stability parameter of the KGT-constrained dendrite growth model does not have a direct significant impact on the macrosegregation formation. It, however, visibly influences the undercooling along the front, separating different dendritic structures and the size of the undercooled melt region where the equiaxed grains can develop. It also affects the amount of eutectic phase created.

To the best of the authors’ knowledge, this is the first attempt at estimating the influence of some inaccuracies, caused by possible ambiguities in choosing the stability constant of the KGT law, on numerically predicted macroscopic fields of solute concentration, the developing zones of columnar and equiaxed crystals and the macrosegregation patterns.

This study aims to answer the question whether investment funds managers exhibit behavioural biases in their investment decisions. Furthermore, it investigates if fund managers, as a group of institutional investors, make decisions in response to central bank’s communication as well as other information in relation to various behavioural inclinations.

A comprehensive study was conducted based on a questionnaire, which is composed of three main parts exploring: (1) general information about the funds under the management of the surveyed group of fund managers, (2) factors that influence the investment process with an emphasis on the National Bank of Poland communication and (3) behavioural inclinations of the surveyed group. Cronbach’s alpha statistic was applied for measuring the reliability of the survey questionnaire and then chi-squared test was used to investigate the relationships between the answers provided in the survey.

The central bank’s communication matters for investors, but its impact on their decisions appears to be only moderate. Interest rates were found to be the most important announcements for investment fund managers. The stock market was the most popular market segment where the investments were made. The ultra-short time horizon played no, or only small, role in the surveyed fund managers’ decisions as most of them invested in a longer horizon covering 1 to 5 years. Moreover, most respondents declared that they considered in their decisions the information about market expectations published in the media. Finally, majority of the fund managers manifested limited rationality and were subject to behavioural biases, but the decisions and behavioural inclinations were independent and, in most cases, they did not influence each other.

The results reported in this study can be used in practice to better understand and to improve the fund managers’ decision-making processes.

Apart from the commonly tested behavioural biases in the group of institutional investors in the existing literature, such as loss aversion, disposition effect or overconfidence, this paper also focuses on the less intensively analysed behavioural inclinations, i.e. framing, illusion of the control, representativeness, sunk cost effect and fast thinking. The originality of this study further lies in the way the research was conducted through interviews with fund managers, who were found to be subject to behavioural biases, although those behavioural inclinations did not influence their investment decisions. This finding indicates that professionalism and collectivism in the group of institutional investors protect them from irrationality.

A generalized time finite element method is considered for time integration of non‐linear equations of motion arising from dynamic problems. A simple three‐time level family of schemes is obtained. Evaluation of the schemes shows that the proposed approach may lead to unconditionally stable algorithms for non‐linear problems. Numerical examples show the accuracy and efficiency of the proposed algorithm in comparison to Newmark's average acceleration method and four order accurate explicit algorithm.