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Number of results: 192
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Abstract

Cyanobacterials (Cyanophyta) belong to phytoplancton. In normal stale concentration of cyanobacterial cells in water rangs between a few hundreds to a few thousands in I drn' of water but while blooming may be increased even to one million in I dm3. At this time water has characteristic color, depending on dominated species. Also characteristic smell is the results of the presence ofcyanobacterial and phytoplankton cells producing odour substances. The cyanobacterial blooms are very important hygienic problem for both human and animal health. While blooming they form foams and head coating on water surface. Also cyanobacterial toxins are huge problem. Cyanobacteria may produce acute toxins such as hepatotoxic peptides (microcystins, nodularins and cylindrospermopsin) and neurotoxic alkaloids (anatoxin-a, anatoxin-a(s), homoanatoxin and aphanotoxins). Cyanobacterial toxins are very dangerous substances which can intoxicate hepatocytes and the nervous system in humans and animals. In this situation it is very important to remove them effectively in water pretreatment processes. In the present paper have been presented for the first time in Poland data on removing cyanobacterial toxins from water in pretreatment process with application of chlorine dioxide and ozone on the example of Sulejów - Łódź water pipe system. In period I 998-200 I the effectiveness rnicrocystin-LR removal ranged between 74--92% while for other izoforms they were between 45-94%.
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Authors and Affiliations

Andrzej K.M. Kabziński
Helena Grabowska
Jerzy Cyran
Renata Juszczak
Józef Dziegieć
Alicja Zawadzka
Dominik Szczukocki
Konrad Szczytowski
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Abstract

The role of mentors is waning: young Polish scientists, efficient at winning their own grants and proficient at English, are growing increasingly independent.

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Authors and Affiliations

Jan Strelau
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Abstract

Integracja badań polarnych w Polsce w ramach Komitetu Badań Polarnych PAN, Polskiego Konsorcjum Polarnego i Centrum Studiów Polarnych KNOW to sukces krajowego środowiska polarnego. Dzięki niej możliwe było wypracowanie Strategii Polskich Badań Polarnych (SPBP).

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Authors and Affiliations

Agnieszka Kruszewska
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Abstract

The Bulletin of the Polish Academy of Sciences: Technical Sciences (Bull.Pol. Ac.: Tech.) is published bimonthly by the Division IV Engineering Sciences of the Polish Academy of Sciences, since the beginning of the existence of the PAS in 1952. The journal is peer‐reviewed and is published both in printed and electronic form. It is established for the publication of original high quality papers from multidisciplinary Engineering sciences with the following topics preferred: Artificial and Computational Intelligence, Biomedical Engineering and Biotechnology, Civil Engineering, Control, Informatics and Robotics, Electronics, Telecommunication and Optoelectronics, Mechanical and Aeronautical Engineering, Thermodynamics, Material Science and Nanotechnology, Power Systems and Power Electronics.

Journal Metrics: JCR Impact Factor 2018: 1.361, 5 Year Impact Factor: 1.323, SCImago Journal Rank (SJR) 2017: 0.319, Source Normalized Impact per Paper (SNIP) 2017: 1.005, CiteScore 2017: 1.27, The Polish Ministry of Science and Higher Education 2017: 25 points.

Abbreviations/Acronym: Journal citation: Bull. Pol. Ac.: Tech., ISO: Bull. Pol. Acad. Sci.-Tech. Sci., JCR Abbrev: B POL ACAD SCI-TECH Acronym in the Editorial System: BPASTS.

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Authors and Affiliations

Jan Strelau
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Abstract

In this paper, we describe secure gateway for Internet of Things (IoT) devices with internal AAA mechanism, implemented to connect IoT sensors with Internet users. Secure gateway described in this paper allows to (1) authenticate each connected device, (2) authorise connection or reconguration performed by the device and (3) account each action. The same applies to Internet users who want to connect, download data from or upload data to an IoT device. Secure Gateway with internal AAA mechanism could be used in Smart Cities environments and in other IoT deployments where security is a critical concern. The mechanism presented in this paper is a new concept and has been practically validated in Polish national research network PL-LAB2020.

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Authors and Affiliations

Dominik Samociuk
Błażej Adamczyk
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Abstract

Renewable energy development is crucial for resolving global warming issues and achieving

sustainable development goals. The objective of this paper is to reveal renewable energy trends

using statistical data to identify the most developed technologies in the field, their distribution by

territory, checking the interrelation between investments in R&D and patent activity.

The changes in total investments made in renewables are studied for 2004–2019 and the increasing

trend has been observed with some fluctuations in certain years, major current investments in solar

and wind energy are detected. The dynamics of international patenting activity in solar and wind

technologies, geothermal and fuel cells, the total number of PCT applications over the past 10 years

by geographic region are considered. The results show some differences across various renewable

technologies. Solar is the most patented, wind and fuel cells are less patented but solar and wind

have shown an uptrend for the last five years, while fuel cell technologies showed a decline after

2008. Geothermal is the least patented.

The comparison between investment and patent application trends in renewables undercovers some

important issues – the leading role of Japan in patenting under the PCT procedure, while China is

a major investor in renewable energy; the US and Europe with big investments in renewables are

also leading in patent registration.

Correlation between investment in R&D and patenting activity in the field of global renewable

energy should be emphasized (correlation coefficient R = 0,849 for 2002–2019). Since private

and public investment is strongly stimulated by domestic renewable energy policies, IP indicators

can help identify policy instruments and their effectiveness within the further research

framework.

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Authors and Affiliations

Tetiana Sobolieva
ORCID: ORCID
Nataliia Harashchenko
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Abstract

This article discusses the issue of hypermodernity, which was studied as part of the research project Poles in the World of Late Capitalism. The article presents biographical models of hypermodernity and strategies of coping with hypermodern ideology, that is, cyclothymias, conversions, and hypermodern episodes.

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Authors and Affiliations

Kamila Biały
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Abstract

The Sin Quyen deposit is characterized by a high accumulation of rare earth elements (REE). This deposit belongs to the IOCG type copper deposits (Iron Oxide Copper-Gold Deposits). In the deposit, the REE carrier minerals have been identified as follow: allanite, titanite, uraninite, monazite, apatite, chevkinite, aeschynite, bastnäsite, and epidote. In the skarn zone, contents of allanite range from single percentages to 10% in hand-size specimens. Locally, minerals of epidote subgroup which occur in large amounts in the host rocks are important. The studied allanites have concentrations of: REE (14–27 wt%), Ca (9–16 wt%), Al (8–19 wt%), Si (26–34 wt%) and Fe (12–21 wt%). Two populations of allanite are documented, the first is texturally older and probably related to the Ca-K alteration (second stage of crystallization). This population has higher REE concentration ranging from 20 to 27 wt%. The second population is texturally younger and has a lower total REE concentration ranging from 14 to 19.9 wt%, which occur mostly as a rim surrounding the older and likely arose during the K alteration with Cu-Au mineralization (third crystallization). The chemical composition indicates that the studied allanites belong to the Ce-La-ferriallanite family, with low ΣHREE and an average of 0.21 wt.%. A temperature of 355°C which was calculated using a value of δ34S isotopes is interpreted as a temperature of the second crystallization stage of allanite. In the studied deposit, excluding allanite and titanite, the other bearing REE minerals have an insignificant role in the REE balance, since they either have the total content of REE, which is often close to the WDS detection limit (rf. the epidote subgroup), or their only occur at the single points. The content of total REE in accessory uraninites is high and range from 1.311% up to 7.959% with an average value of 4.852%.
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Authors and Affiliations

Nguyen Dinh Chau
1
ORCID: ORCID
Jadwiga Pieczonka
1
ORCID: ORCID
Adam Piestrzyński
1
ORCID: ORCID
Le Khanh Phon
2
Duong Van Hao
2

  1. AGH Unversity of Science and Technology, Kraków, Poland
  2. Hanoi University of Mining and Geology, Hanoi, Vietnam
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Abstract

In this paper, there are presented the main principles of the navigational and hydrographical provision of ships' special tasks. There are specified the types of ships' tasks, but especially, ships' special tasks. There is discussed the ship's navigation process as the function of the type of the ships tasks. There is also presented the substance of the navigational and hydrographical provision of the ships' special tasks, as well as the development trends of this provision.
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Authors and Affiliations

Zdzisław Kopacz
Wacław Morgaś
Józef Urbański
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Abstract

The choice of global geopotential model used in remove-restore technique for determination of regional quasi geoid from gravity data may affect the solution, in particular when the accuracy is supposed to reach a centimetre level. Global geopotential model plays also an important role in validating height anomalies at GPS/levelling sites that are used for the estimation of the external accuracy of quasigeoid models. Six different global geopotential models are described in the paper. Three kinds of numerical tests with use of terrestrial gravity data and GPS/levelling height anomalies were conducted. The first one concerned comparison of height anomalies at GPS/levelling sites ia Poland with corresponding ones computed from various global geopotential models. In the second one the terrestrial gravity anomalies in Poland and neighbouring countries were compared with corresponding gravity anomalies computed from global geopotential models. Finally the quasigeoid models obtained from gravity data with use of different global geopotential models were verified against corresponding height anomalies at GPS/levelliag sites in Poland. Data quality was discussed and best fitting global geopotential model in Poland was specified.
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Authors and Affiliations

Jan Kryński
ORCID: ORCID
Adam Łyszkowicz
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Abstract

This paper presents a geeral concept of an adjustment method Edgeworth series applied. The author proposes to replace distributions with approximating functions representd by Edgeworth series, which would be a universal, probabilistic model of the adjustment problem. Special attention is paid to variance an lysis. A con variance matrix C, of the vector X, its estimate C,, and and estimate of the variance coefficient a0 are derived. Also some further properties of the proposed method are presented.
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Authors and Affiliations

Andrzej Dumalski
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Abstract

Previous research reported about high comorbidity between asthma and neurodevelopmental disorders. Recently, asthma was associated also with executive functions poorness. The current study aimed to investigate the verbal and visual memory performances among fifteen asthmatic kindergarten children compared to the performances of other fifteen healthy kindergarten children. The results showed that the asthmatic group revealed poor performances in the immediate short term verbal memory and the verbal working memory tests but not in the verbal learning test as it was compared to the healthy group. In addition, the asthmatic group revealed poor performances in the visual memory tasks compared to the healthy group. The results were explained in light of the assumption that poor executive functions might be interfere the process of managing the attentional resources which are needed through the process of memory encoding and retrieval.

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Authors and Affiliations

Haitham Taha
Mahmood Khalil
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Abstract

The problem of outlying observations is very well-known in the surveying data processing. Outliers might have several sources, different magnitudes, and shares within the whole observation set. It means that it is not possible to propose one universal method to deal with such observations. There are two general approaches in such a context: data cleaning or robust estimation. For example, the robust M-estimation has found many practical applications. However, there are other options, such as R-estimation or the absolute M split estimation. The latter method was created to be less sensitive to outliers than the squared M split estimation (the basic variant of Msplit estimation). From the theoretical point of view, the absolute M split estimation cannot be classified as a robust method; however, it was proved that it could be used in such a context under certain conditions. The paper presents the primary comparison between that method and a conventional robust M-estimation. The results show that the absolute M split estimation predominates over the classical methods, especially when the percentage of outliers is high. Thus, that method might be used to process LiDAR data, including mismeasured points. Processing synthetic data from terrestrial laser scanning or airborne laser scanning confirms that the absolute M split / estimation can deal with outliers sufficiently.
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Authors and Affiliations

Robert Duchnowski
1
ORCID: ORCID
Patrycja Wyszkowska
1
ORCID: ORCID

  1. University of Warmia and Mazury, Olsztyn, Poland
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Abstract

The suitability of a land plot in a real estate market could be identified as a good investment because the land plot is deemed as popular. This activity is important for economic growth, who is one of the sustainable development goals. Mostly, all research in this field is focused on sustainability as well as the opinions of professionals. However, this field should be explored from another side which is based on real geodata. Criteria and its weight are very important in decision support systems. The correct criteria can help in selection of the best real estate object for an investment, but it is not only useful but also and a challenging task that has not yet been solved. The methods of research are data graphical analysis, correlation, decision supporting systems, etc. The research aims at determining the significance of the connections and using them as the criteria in the selected decision supporting method. In addition, it will be determined which decision supporting method defines the most suitable object for investment. These new criteria are proposed for operation in the land use models. Furthermore, it has been identified as one criterion, which is significant in the urban and agrarian territories. Also it turned out, that the land plot is the most active when it is as far from a densely built-up residential territory as possible and as close to a school, and when the land plot is as large as possible.

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Authors and Affiliations

Rimvydas Gaudesius
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Abstract

Bilingualism has long been observed in Silesia, a part of Poland which lies on the border between three cultures and languages: Polish, Czech and German. Some lin-guists consider Silesian one of the Polish dialects, others think it should be treated as a separate language. During the communist times the inhabitants of Upper Silesia were discouraged from using the local dialect at school or in public institutions. The situation has changed a lot since 1989 with the promotion of regional studies. Short characteristics of Silesian will be presented in the fi rst part of the paper.The main part of the project presents the results of a questionnaire which focuses on young people’s attitudes towards Silesian. The respondents (100 Polish students of English philology) fall into two groups – half of them identify themselves with the region and the other half do not. How many respondents speak Silesian? Where do they use it and how do they evaluate it? What is the linguistic stereotype of a person living in Upper Silesia? These are just a few questions that suggest themselves in the context of the study.

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Authors and Affiliations

Urszula Wieczorek
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Abstract

Speech is almost never delivered in ideal quiet conditions. On the contrary, the acoustic signal reaching a listener's ears is degraded by background noise and reverberations. The current study investigates the perception of the voicing contrast of initial stops in English by Polish non-native listeners. Previous research showed that Polish learners do not match native speakers of English in production and perception of English voiced and voiceless stops, which results from different phonetic implementations of voicing in the two languages. In the current study, two groups of Polish listeners recognised voicing of English initial stops in one-syllable words both in quiet and in six-talker babble. The results revealed different patterns of recognition for the two conditions. The place of articulation interacted significantly with voicing both in quiet and in noise, however results obtained suggest that performance in noise did not simply reflect the performance in quiet.

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Authors and Affiliations

Arkadiusz Rojczyk
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Abstract

Qualitative migration researchers today often use one or more of three concepts – mobility, transnationalism and integration – to make sense of the complexities of contemporary migrants’ lives. Collectively, researchers identify these as the three fundamental characteristics of migranthood. Being a migrant is about, for example, planning return visits, maintaining (or not maintaining) relations with people in the sending country or being preoccupied with learning to speak the receiving-society majority language. Qualitative interviewing suggests that each migrant is uniquely situated along various mobility, transnational and integration continuums. Migrants have many social identities as well as migranthood and the existence of these other, intersecting, social identities (such as social class, lifestage and gender) helps to determine their location on the continuums: for example, how often they are mobile and how much they can be mobile. The article draws on interviews in Poland with Ukrainians and Polish return migrants to show how (former) migrants conceptualise shared Ukrainian-Polish migranthood along these three continuums.
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Authors and Affiliations

Anne White
1
ORCID: ORCID

  1. UCL School of Slavonic and East European Studies (SSEES), UK
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Abstract

Drawing on extensive qualitative research into experiences of migration and settlement among Central and East European (CEE) migrants living in Scotland, this article examines the role of intersecting emotional and material (in)securities in migrant families’ decision-making regarding and experiences of longer-term settlement. The article queries fixed or given understandings of either ‘family’ or ‘secu-rity’ and explores the complex and sometimes contradictory relationship between them. In so doing, it makes a number of significant and interconnected theoretical and empirical contributions to existing research in the field of family migration. Through a critical analysis of the relationship between family and (in)security the article offers nuanced insight into the ways in which family processes of reunion, separation and (re)formation link to decisions regarding migration and settlement. The intersecting and sometimes contradictory forms of emotional and material support, obligation and vulnerability which both family relations and processes of migration and settlement entail are critically analysed by bring-ing together theoretical frameworks of social (in)security and understandings of family as ‘made’ rather than ‘given’. Finally, attention given to the temporal aspects of (in)security, as well as the transnational aspects of migrants’ lives, provides new ways of understanding the open-endedness of decision-making processes relating to migration and settlement, especially where these involve multiple decision-makers.

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Authors and Affiliations

Rebecca Kay
Paulina Trevena
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Abstract

Energy management plays a crucial role in cabin comfort as well as enormously affects the driving range. In this paper energy balances contemplating the implementation of a heat pump and an expansion device in battery electric vehicles are elaborated, by comparing the performances of refrigerants R1234yf and R744, from –20°C to 20°C. This work calculates the coefficient of performance, energy requirements for ventilation (from 1 to 5 people in the cabin) and energy required with the implementation of a heat pump, with the employment of a code in Python with the aid of Cool- Prop library. The work ratio is also estimated if the work recovery device recuperates the work during the expansion. Comments on the feasibility of the implementation are as well explicated. The results of the analysis show that the implementation of an expansion device in an heat pump may cover the energy requirement of the compressor from 27% to more than 35% at 20°C in cycles operating with R744, and from 15% to more than 20% with refrigerant R1234yf, considering different compressor efficiencies. At –20°C, it would be possible to recuperate between around 30 and 24%. However, the risk of suction when operating with R1234yf at ambient temperatures below –10°C shows that the heat pump can only operate with R744. Thus, it is the only refrigerant that achieves the reduction of energy consumption at these temperatures.
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Authors and Affiliations

Maria Laura Canteros
1
Jiri Polansky
2

  1. Czech Technical University in Prague, Jugoslávských partyzánu 1580/3, 160 00 Prague 6 – Dejvice, Czech Republic
  2. ESI Group, Brojova 16, 326 00 Plzen, Czech Republic
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Abstract

The development of a reliable mathematical model of an axial compressor requires applying flow and efficiency characteristics. This approach provides performance parameters of a machine depending on varying conditions. In this paper, a method for developing characteristics of an axial compressor is presented, based on general compressor maps available in the literature or measurement data from industrial facilities. The novelty that constitutes the core of this article is introducing an improved method describing the performance lines of an axial compressor with the modified ellipse equation. The proposed model is extended with bleed air extraction for the purposes of cooling the blades in the expander part of the gas turbine. The variable inlet guide vanes angle is also considered using the vane angle correction factor. All developed dependencies are fully analytical. The presented approach does not require knowledge of machine geometry. The set of input parameters is based on reference data. The presented approach makes it possible to determine the allowed operating area and study the machine’s performance in variable conditions. The introduced mathematical correlations provide a fully analytical study of optimum operating points concerning the chosen criterion. The final section presents a mathematical model of an axial compressor built using the developed method. A detailed study of the exemplary flow and efficiency characteristics of an axial compressor operating with a gas turbine is also provided.
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Authors and Affiliations

Paweł Trawiński
1

  1. Institute of Heat Engineering, Warsaw University of Technology, Nowowiejska 21/25, 00-665, Warsaw, Poland
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Abstract

In this work we analyse basic characteristics of Love wave sensors implemented in waveguide structures composed of a lossy viscoelastic surface layer deposited on a lossless elastic substrate. It has to be noted that Love wave sensors working at ultrasonic frequencies have the highest mass density sensitivity $S_σ^(v_p )$ among all known ultrasonic sensors, such as QCM, Lamb wave or Rayleigh wave sensors. In this paper we have established an exact analytical formula for the mass density sensitivity $S_σ^(v_p )$ of the Love wave sensors in the form of an explicit algebraic expression. Subsequently, using this developed analytical formula, we compared theoretically the mass density sensitivity $S_σ^(v_p )$ for various Love wave waveguide structures, such as: (1) lossy PMMA surface layer on lossless Quartz substrate and (2) lossy PMMA on lossless Diamond substrate. The performed analysis shows that the mass density sensitivity $S_σ^(v_p )$ (real and imaginary part) for a sensor with a structure PMMA on Diamond is five times higher than that of a PMMA on Quartz structure. It was found that the mass density sensitivity $S_σ^(v_p )$ for Love wave sensors increases with the increase of the ratio: bulk shear wave velocity in the substrate to bulk shear wave velocity in the surface layer.
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Authors and Affiliations

Piotr Kiełczyński
1
Marek Szalewski
1
Andrzej Balcerzak
1
Krzysztof Wieja
1

  1. Institute of Fundamental Technological Research Polish Academy of Sciences Warsaw, Poland
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Abstract

None of us lives in the world as it simply exists. Rather, each of us inhabits a specific “image of the world” – one which we did not create ourselves, but which we usually mistake for the real world itself.
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Authors and Affiliations

Krzysztof Moraczewski
1

  1. Institute of Cultural Studies, Adam Mickiewicz University in Poznań
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Abstract

On a few examples of aquatic metaphors that invoke some of the most important philosophical concepts.

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Authors and Affiliations

Daniel Roland Sobota

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