This paper presents the design of digital controller for longitudinal aircraft model based on the Dynamic Contraction Method. The control task is formulated as a tracking problem of velocity and flight path angle, where decoupled output transients are accomplished in spite of incomplete information about varying parameters of the system and external disturbances. The design of digital controller based on the pseudo-continuous approach is presented, where the digital controller is the result of continuous-time controller discretization. A resulting output feedback controller has a simple form of a combination of low-order linear dynamical systems and a matrix whose entries depend nonlinearly on certain known process variables. Simulation results for an aircraft model confirm theoretical expectations.
The paper presents areas where the EBITDA measure is used in coal companies. The metric and the ratios where it is utilized are employed to assess companies and management efficiency, hence they are used as criteria for rewarding board members. EBITDA-based ratios are also used to evaluate the profitability of company restructuring and its goodwill in mergers and acquisitions. EBITDA, also tends to be used to value companies on the capital market. It is a good tool for efficiency assessment in coal companies with relatively stable fixed assets and small share of intangible assets, which amortized over short periods of time could interfere the comparability of relations based on this measure. The comparability is also disturbed by large investment expenditure incurred in the short term. This does not apply to the mining industry, in which investment cycles are long, last several years and expenditures are spread over time. In addition, the rate of technical progress imposing the need to implement large technology projects is not high compared to technology companies with high development dynamics.
EBITDA based ratios were used to assess a number of listed coal companies. The analysis revealed that the profit/loss of these companies is mainly determined by coal prices. The cost of coal mining is 90% fixed and projects undertaken to reduce it bear fruit only over the long term. Cyclically changing coal prices cause major losses in companies when prices are low, which leads to bankruptcies or a need to restructure. After a period of decline in 2014–2016, the profit/loss of Polish coal companies as well as companies from around the world improved in 2017–2018. T he financial standing of Polish companies was better than that of their counterparts from other parts of the world.
The present paper deals with a late medieval culinary collection, Liber Cure Cocorum. The collection differs from the other known culinary manuscripts of the time due to its being written in verse. Altogether the poem consists of 137 recipes and four other fragments which introduce four sections of the collection: pottages, sauces, roast foods and ‘small cookery’. Most of the instructions included in Liber Cure Cocorum are known from other medieval collections, written in prose (cf. Hieatt 2006). In the article the collection will be analysed from two perspectives. First, the struc-ture of culinary poems will be discussed in order to examine the degree of their compliance with the traditional model of the medieval recipe. Next, although the authorship of the collection is anonymous, we will try to reveal who its author was and whom he meant as the target audience. For this purpose, we will pay attention to fragments in which the author directly refers to himself and/or to the potential reader. Additionally, any details included in the particular recipe components which might expose the potential poet and/or the audience will be discussed. By looking closely at the structure of the recipes and the intended audience, we will try to an-swer the question why it was written in verse rather than in prose.
The present paper is concerned with conceptualisations of Strategic Business Units (SBUs) that appear in a specific piece of business discourse – the Boston Consulting Group (BCG) matrix. More specifically, the authors analyse both the names and the language used to talk about the SBUs. The data for the research comes from three languages: English, Polish, and French, the fi rst of which is the source language of the terminology, while the other two are target languages into which the terminology was rendered. Since the analysed phenomena are chiefl y metaphors and metonymies, the theoretical framework was provided by the Conceptual Metaphor Theory and Conceptual Metonymy Theory.
This article discusses and expands on two related issues. The first is the unexplored reasons for the departure of Polish migrant women: the forced migration phenomenon. The author describes the system behind forced migration as created at the intersections not only of care, gender and migration regimes but also of legal regimes. Second, the author points out that the close relation between forced migration and the process of ‘unbecoming a wife in the transnational context’ creates a distinctive type of trans-national motherhood experience. In order to explain the specificity of these types of experiences better the author introduces a new typology of transnational motherhood biographies. The case study of Al-dona is representative of the experiences of some Polish women in the period under study, 1989–2010.
This article is devoted to contemporary return migrations by Kazakhs – a process of great significance for the population and cultural policies of the government of independent Kazakhstan. I examine the repatriation process of the Kazakh population from the point of view of the cultural transformations of Kazakh society itself, unveiling the intended and unintended effects of these return migrations. The case of the Kazakh returns is a historically unique phenomenon, yet it provides data permitting the formulation of broader generalisa-tions. It illustrates the dual impact of culturally different environments, which leads to a simultaneous pre-serving and changing of the culture of the new immigrants. The analyses found in this article are based upon data collected during two periods of fieldwork conducted in June–July 2016 and March 2018 at several locations in Kazakhstan and in cooperation with a Kazakh university. The research methodology is anchored in multi-sited, multi-year fieldwork.
This article examines the connection between media use and social in/security from the perspective of Finnish Russian-speakers. Based on 25 interviews conducted in Finland in 2015–2016, it analyses the ways in which people in conflict situations mitigate social risks and attempt to produce security by governing their use of the media. Drawing from von Benda-Beckmann and von Benda-Beckmann’s work on social security, the article argues that security studies ought to include transnational media use in their scope and broaden the emphasis towards the social and societal aspects of threat and insecurity. Furthermore, it explains how, in times of conflict, transnational media may turn into a digitalised ‘war zone’ with alarming consequences on the identification and social security of their audiences.
The article concerns computer modelling of processes in cooling systems of internal combustion engines. Modelling objectives and existing commercial programs are presented. It also describes Author’s own method of binding graphs used to describe phenomena in the cooling system of a spark ignition engine. The own model has been verified by tests on the engine dynamometer. An example of using a commercial program for experimental modelling of an installation containing a heat accumulator is presented.