In the first part of the article, Krzysztof A. Makowski describes how the idea of granting Poland the opportunity to host the 23rd International Congress of Historical Sciences in 2020 in Poznań came about and how Poznań’s application to host the Congress was prepared. Moreover, the author presents the ongoing preparations for the Congress. In the second part of the article, Ewa Domańska discusses the origins and evolution of the idea of “alter-native modernities” and “epi- stemic justice” as leitmotifs of Poznań’s application. She stresses the need and importance of developing an intellectual alliance of East-Central European countries and lists activities that could help raise the region’s status as an important centre of knowledge building.
The authors attempted to present the state of disputes regarding the delimitation of marine areas based on a discussion of the practices of countries in the East China Sea and the Sea of Japan region. The authors describe the disputes regarding the islands of Senaku (Diaoyu) between both China and Taiwan and Japan and those over the Dokdo (Takeshima) archipelago between the Republic of Korea and Japan. There are many similarities between these two marine territorial disputes. The core of the disputes is land that is devoid of significant economic importance. Due to this, these areas were not previously of interest to coastal countries. They came to the forefront when their location facilitated determining exclusive economic zones. This intensified when evidence of crude oil and natural gas resources was detected in these areas. Tensions eased when geological reports revealed that initial estimates were overly optimistic. The fundamental cause of disputes over archipelagos is that they can be used to determine exclusive economic zones. The problem is compounded when the politicians of Eastern Asia incite historical remembrance. This is especially evident in the cases of Japan, the Republic of Korea, Taiwan, and China, whose governments are, to some extent, hostages of ultra-nationalistic factions.
The paper presents a modelling mathematical tool for prediction of dynamic and steady-states operation of the single-phase capacitor induction motor for different values of the capacitor capacitance and different frequency of voltage supply at no-load and rated load conditions. Developed mathematical model of the capacitor induction motor was implemented for calculation using Matlab/Simulink software. Presented simulation results may be utilized to achieve better starting quality of single-phase capacitor induction motors.
The purpose of the paper is the investigation of possibility of utilization of a single-phase induction machine, designed and normally operating as a single-phase capacitor induction motor, as a self-excited single-phase induction generator, which can be used to generate electrical energy from non-conventional energy sources. The paper presents dq model of the self-excited single-phase induction generator for dynamic characteristics simulation and steady-state model based on double revolving field theory with two phase symmetrical components – a forward and backward revolving field for performance of the generator under resistive load. Excitation and load characteristics obtained by simulation showed considerable influence of method of capacitor configuration in the load stator winding on terminal voltage, current and output power of the generator under load. An specific construction of the stator windings together with capacitor requirements to obtain nominal output power at desired self-regulating terminal voltage over the operating range will be the aim of further research.
Simulations of turbulent mixing in two types of jet mixers were carried out using two CFD models, large eddy simulation and κ-ε model. Modelling approaches were compared with experimental data obtained by the application of particle image velocimetry and planar laser-induced fluorescence methods. Measured local microstructures of fluid velocity and inert tracer concentration can be used for direct validation of numerical simulations. Presented results show that for higher tested values of jet Reynolds number both models are in good agreement with the experiments. Differences between models were observed for lower Reynolds numbers when the effects of large scale inhomogeneity are important.