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Number of results: 8
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Abstract

Affine discrete-time control periodic systems are considered. The problem of global asymptotic stabilization of the zero equilibrium of the closed-loop system by state feedback is studied. It is assumed that the free dynamic system has the Lyapunov stable zero equilibrium. The method for constructing a damping control is extended from time-invariant systems to time varying periodic affine discrete-time systems. By using this approach, sufficient conditions for uniform global asymptotic stabilization for those systems are obtained. Examples of using the obtained results are presented.
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Authors and Affiliations

Adam Czornik
1
Evgenii Makarov
2
Michał Niezabitowski
3
Svetlana Popova
4
Vasilii Zaitsev
4

  1. Faculty of Automatic Control, Electronics and Computer Science, Silesian University of Technology, 44-100 Gliwice, Poland
  2. Institute of Mathematics, National Academy of Sciencesof Belarus, 220072 Minsk, Belarus
  3. Faculty of Automatic Control, Electronics and Computer Science,Silesian University of Technology, 44-100 Gliwice, Poland
  4. Udmurt State University, 426034 Izhevsk, Russia
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Abstract

The protection of copper and silver ore resources in the Polish Lubuskie Province requires certain steps to be taken, the suggestions for which are presented in this article. It addresses both known and newly discovered ore deposits, as well as prospective areas and places of ongoing exploration, which throughout the paper are collectively recognized as potential Cu-Ag mining areas. The example of Lubuskie Province was chosen as an exceptional region with multiple known areas of copper and silver ore potential, but no active mining operations until now. The study focuses on the nature and location of all potential mining areas in Lubuskie Province, and subsequently suggests the means of their protection which can be implemented today, as well as in the future. Such means should be introduced by way of new or amended legal regulations. Certain major changes to Polish law are necessary to provide sufficient protection of both currently known, as well as possible future deposits, against such use of land which would prevent the extraction of their resources. The study shows that the legal regulations effective in Poland today are insufficient or too vague, as they do not include any provisions concerning prospective resources, as well as areas of active mineral exploration, instead focusing solely on officially registered mineral deposits. Therefore, the proposals of new solutions providing better protection of all potential Cu-Ag mining areas are presented in this article.
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Authors and Affiliations

Krzysztof Zieliński
1
ORCID: ORCID
Stanisław Speczik
2 1
ORCID: ORCID
Tomasz Bieńko
2 1
ORCID: ORCID
Alicja Pietrzela
2 1
ORCID: ORCID

  1. Miedzi Copper Corporation, Warszawa, Poland
  2. University of Warsaw
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Abstract

The study considers remittances as part of the lifeworlds of immigrants in multiple interactions with return intentions and communication with those left behind. This is an alternative view of the standard approach to remittances as a possible source of development or as a variable to be explained by family solidarity, investment projects or the reasons for return. The key dependent variable is the home orien-tation of immigrants as a function of remittances, return intentions and communication behaviours, measured in quantitative and typological terms. The typological analysis of home orientation diverges from the standard approach, which is in terms of high or low intensity of cross-border activities of remitting or communicating between immigrants and those they have left behind. It argues for the fact that cross-border activities combine in different ways to generate specific social types of remitting prac-tices. The remitting behaviours of migrants are, in our approach, multidimensional, encompassing eco-nomic, social and cultural content. Three hypotheses are formulated on: 1) collective deprivation in remitting money; 2) survival–development–identification strategies of migrants’ families; and 3) higher predictability of home orientation compared to economic remitting behaviours. In this context, higher predictability means greater variation of the synthetic variable of home orientation by social, cultural and economic factors as compared to the impact of the same factors on the more abstract variable of economic remittances.

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Authors and Affiliations

Dumitru Sandu
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Abstract

In the era of the fight against global warming and in light of the search for energy with the least possible impact on the environment, interest in hydrogen has become a natural direction of development. Striving for a zero-emission Europe by 2050, the EU promotes low-emission and ultimately emission-free hydrogen for the widest possible use in the economy. Poland has developed a strategic document specifying the necessary activities for the use of hydrogen in the economy, which should at the same time maintain its competitiveness. Poland is currently the third producer of hydrogen in the European Union, which enables strategic thinking about maintaining Poland as a leading player on the hydrogen market in the long term. Currently, hydrogen in Poland is produced by (usually large) state-owned enterprises for their own needs with only a small margin of its resale. This is conventional hydrogen that is mainly obtained from natural gas. Therefore, it is difficult to talk about the hydrogen market, which must develop so that this raw material can be widely used in many branches of the modern economy. However, this requires taking a number of legislative, research and development and investment activities, as well as directing the national energy transformation to renewable energy sources, which may ultimately reduce the costs of pure hydrogen production. A number of actions have been taken, but the delay in legislative actions is slowing down the creation of the hydrogen market and is limiting the interest of private businesses in engaging in transformation activities.
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Authors and Affiliations

Aleksandra Komorowska
1
ORCID: ORCID
Eugeniusz Mokrzycki
1
ORCID: ORCID
Lidia Gawlik
1
ORCID: ORCID

  1. Mineral and Energy Economy Research Institute PAS, Poland
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Abstract

Foreskin, apart from its literal meaning, functions in Tanach also as a metaphor of blemish. Similarly, the circumcision is presented as a removal thereof. The perfecting function of the rite is visible in Second Temple texts, as well as in later tannaitic sources. The purpose of this paper is to analyze words of Jesus found in J 7:22–23 in the light of circumcision in the Hebrew Bible, understood as a ritual performed to remove a blemish. The conclusion is that Jesus’ words in the analyzed verses continue the biblical view, attesting to an exegetical trend visible in later Jewish sources.
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Authors and Affiliations

Jakub Pogonowski
1

  1. University of Warsaw, Poland
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Abstract

Polish maritime law jurisprudence defines a contract for a sea trip as a mixed agreement, comprising terms implied by the Civil Code and terms expressly devised by the parties. The Supreme Court case law confirms that view.

The Civil Code does not explicitly define the sea travel contract. The sea trip contract is governed by the Act on Tourist Services (1997), implementing the Council Directive 90/314/EEC on package travel, package holidays and package tours. However, matters outside the scope of the 1997 Act are covered by the Civil Code.

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Authors and Affiliations

Iwona Zużewicz-Wiewiórowska
ORCID: ORCID
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Abstract

A new genus and species of heteronemertean from the Antarctic (Bellingshausen Sea), Oligodendrorhynchus hesperides , is described and illustrated. Some morphological features with major systematic significance are following: the mode of branching of the proboscis and its low number of terminal branches; the lack of horizontal lateral cephalic slits but in their place a pair of shallow epidermal depressions; a gelatinous amorphous connective stratum between the outer longitudinal and circular muscle layers; the presence of a rhynchocoelic nerve; isolated fibres of the rhynchocoel circular muscle layer interwoven with bundles of the adjacent body−wall inner longitudinal muscle fibres in the intestinal region. Other anatomical characters which can also be used to distinguish the new taxon from existing heteronemertean species that have a branched proboscis are also discussed.
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Authors and Affiliations

Fernando Ángel Fernández-Alvarez
Nuria Anadón

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