This paper explores special bifurcations that appear in dynamical systems possessing codimension-2 discontinuity sets in the state space. In these systems, the vector field has continuously many directional limits at the discontinuity set. It is shown that the trajectories can reach the discontinuity set along specific limit directions. The number and type of these organising objects characterise the behaviour of the dynamics in the vicinity of the discontinuity set. Thus, bifurcations of limit directions have a remarkable effect on the system. In the paper, two special bifurcations are explored; the tangency bifurcation and the saddle–node bifurcation of limit direction are followed through different formulations of the dynamical system. It is demonstrated that these bifurcations appear in rigid body dynamics in the presence of dry friction.

The finite element method is a widely used numerical method to analyze structures in virtual space. This method can be used in the packaging industry to determine the mechanical properties of corrugated boxes. This study aims to create and validate a numerical model to predict the compression force of corrugated cardboard boxes by considering the influence of different cutout configurations of sidewalls. The types of investigated boxes are the following: the width and height of the boxes are 300 mm in each case and the length dimension of the boxes varied from 200 mm to 600 mm with a 100 mm increment. The cutout rates were 0%, 4%, 16%, 36%, and 64% with respect to the total surface area of sidewalls of the boxes. For the finite element analysis, a homogenized linear elastic orthotropic material model with Hill plasticity was used. The results of linear regressions show very good estimations to the numerical and experimental box compression test (BCT) values in each tested box group. Therefore, the numerical model can give a good prediction for the BCT force values from 0% cutout to 64% cutout rates. The accuracy of the numerical model decreases a little when the cutout rates are high. Based on the results, this paper presents a numerical model that can be used in the packaging design to estimate the compression strength of corrugated cardboard boxes.

Lacy phacelia (Phacelia tanacetifolia Benth.), a plant of North American origin, has been cultivated in the Carpathian Basin since the end of the 19th century. It was sown for ornamental purposes, but at the same time its potential for beekeeping was also recognized. It was prophesied to save the future of the Hungarian apiculture, but in the period following the Second World War with the collapse of the large estate system, it was cultivated as a bee pasture only on a small scale. Since the beginning of the 20th century, Hungarian researchers have been studied its forage potential in several experiments. Despite the fi rst contradictory conclusions, it has been respected as a valuable forage crop for several livestock species since the 1970s. Its excellent potential for green manuring and soil disinfection has been also confi rmed in many experiments carried out in the Carpathian Basin for more than a century. Since the end of the 1970s, its exportoriented seed production has boomed both in small and large farms in the Little Hungarian Plain (in NW Hungary). Th is practice has been strongly linked to migratory beekeeping, which has elevated lacy phacelia to the most important melliferous plants producing monofl oral honey in Hungary. Its annual production area has fl uctuated between 1500 and 11,000 ha in the last 20 years.

The decisions of company managers are often not guided by the regulations governing the environment but by subjective factors that exert their effects in a hidden way in the decision-making manager's behavior. Market behavior is objectively controlled by regulators, but subjective factors lead to poor decision-making in some cases. On the one hand, the principal-agent problem is revealed behind the subjective factors, and on the other, cognitive biases affect the decision-making leader as a person. Cooperation with competitors from the same sector and sustainability issues are two similar areas where there is an opportunity to examine these concerns and where the nature of companies' decision-making shows similar or identical patterns on the basis of which decision-making behavior can be explored, characterized, and understood. This thesis examines the attitude of the managers of two existing Courier, Express, and Parcel market players regarding possible market cooperation. In-depth interviews and the completion of a unique questionnaire that revealed the presence of cognitive bias were the basis for the research. During the investigation, the cognitive bias influencing the decision of the two company managers was identified, and it was also examined whether the parent company or the owner's opinion affected their decision. The two case studies demonstrate how managers' decisions to develop collaborations are influenced by their prior experiences and prejudices.

Based on blue-dyer masters’ experience, we can say that people are still interested in the technology of traditional blue dyeing. There are many people participating in trade shows. Moreover, people tend to buy and use the products produced this way. Based on the proposal of the Intellectual Cultural Heritage Professional Committee of the Hungarian National Committee of UNESCO, the tradition of blue dyeing became part of the National Register of Intellectual Cultural Heritage in 2015. Then, in 2018, to the proposal of five countries, including Hungary, the traditional trade of blue-dyeing was recognised, which thus became part of the list of intellectual cultural heritage of UNESCO. In the elaboration of the petition of nomination, a master of Győr, Ildikó Tóth and her family participated. In our study, we are giving an overview of the history of blue-dyeing, which can be dated from the end of the 17^th century, of the spreading of the main techniques, and also of the state of the number of blue-dyers. Beyond the above-mentioned issues, we are dealing with the history of blue-dyeing in Győr, mentioning the more important masters, as well as the mark of the trade, which can be seen until now. In the main part of our study, we are introducing a blue-dyeing workshop in Győr, where they manufacture textiles using original devices and technology until the present day. Apart from this, we are pointing out the family story of the blue-dyer family Éhring, which embraces five generations. Moreover, we are presenting their work done in the survival of our cultural heritage, in popular education and community development, with the help of the interviews made with Ildikó Tóth and her family – who has recently received the title ‘Master of Folk Culture’. In the study, we are also publishing true stories about blue-dyer masters, about the trade and the above-mentioned family.