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Number of results: 16
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Abstract

In this article I will attempt to answer the question of why systemic solutions to (social) problems of Polish economic migrants fail to be instituted in Poland by means of social negotiations. Therefore, while emphasising the social dimension of Polish migration, I briefly present its specificity and point to some associated threats. Referring to the category labelled as social problem, I demonstrate the nature of obstacles which prevent a debate on Polish migration in the area of social negotiations from taking root on public ground in Poland. I also refer to the mechanisms of degradation of the public sphere as those which are preventing the development of systemic solutions to the problems of Polish migrant workers by means of social negotiations.
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Authors and Affiliations

Ireneusz Bochno
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Abstract

This article presents the evolution of the approach to the indicative designation of revitalization areas in Poland at central, regional and local level. The introduction shows rational for monitoring of degradation in Polish cities, i.e. a continuous assessment of its condition, and not just the designation of areas where intervention is needed. Monitoring ensures the comparability of observations and allows to evaluate the results of undertaken measures. Without it, it is impossible to fully assess the effects of revitalization in the previous financial perspectives. The first chapter of the article outlines the requirements for determining areas for revitalization before 2013, the reasons for their adoption, and the indicators used in the delimitations at the time. The second chapter contains the results of a study carried out in the fi rst half of 2016 at the Institute of Urban Development concerning the designation of degraded areas and revitalization areas just after the entry into force of the revitalization law. The results of the study are conclusions confirming the use of cities, which first delimited the areas of revitalization from the possibility of individualizing the approach to the designation of those areas, which was introduced by the Guidelines and the law.

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Authors and Affiliations

Aleksandra Jadach-Sepioło
Bogumiła Krystek-Kucewicz
Krzysztof Kaszuba
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Abstract

The new challenges for Polish theology in the beginning of the 21st c. in the context of possession and exorcism include a theological reflection on possession and exorcism in the Bible, in patristic texts as well as in medieval and modern theological literature. Another issue is an elaboration of a new theological anthropology, which should acknowledge the achievements of human sciences like psychology and psychiatry. The existence of the psychic sphere in the human being is to be distinguished while the human spiritual sphere is to be convincingly justified. More precise criteria will be needed in order to distinguish psychic problems from those of a spiritual nature, including possession.

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Authors and Affiliations

Ks. Leszek Misiarczyk
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Abstract

The public character of school has recently been called into question more often. I examine the question given in the title in terms of three different aspects (juridical, institutional and performative), each of which is linked with a number of disturbing transformations of public schools (privatization of that which is public, re-feudalization, and commodification of education). By virtue of such an analysis and with reference to research on the essence of what is public, I make an attempt to formulate the key meanings of the public character of school.

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Authors and Affiliations

Piotr Zamojski
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Abstract

Jürgen Habermas’ theory of the public sphere has provoked a massive reaction in European historiography in the last thirty years. However, methodological debates driven by the new questions that it inspired in Germany, England, or France had no equivalent in Poland and more broadly in Eastern Europe. This essay suggests why this might have been the case and argues for the deeper engagement of Polish historians with the Habermasian theory. In the text, I reintro-duce the aims of the theory of the public sphere and look for the possible roots of its lacklustre reception among Polish historians in the idea about the Polish case’s supposed incompatibility with the course of modern history assumed by Habermas. I argue against this view, emphasising the flexibility and open‑endedness of the main Habermasian concepts, as well as underlining the necessity for a specifically Polish answer to Habermas’ theoretical enterprise. In the final part, I present the opportunities brought by adapting the theory to the Polish case, claiming that the original history of the Polish public sphere could be a prospective topic for both Polish historians and other historians of the public sphere.
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Authors and Affiliations

Adrian Wesołowski
1
ORCID: ORCID

  1. Jagiellonian University
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Abstract

The effect of large injection rates on the steady laminar compressible boundary layer in the front stagnation-point region of a rotating sphere with a magnetic field has been studied. The effect of variable gas properties, non-unity Prandtl number and viscous dissipation are included in the analysis. The nonlinear coupled ordinary differential equations governing the flow are first linearized using the quasilinearization technique, and the resulting system of linear equations are then solved using an implicit finite-difference scheme with non-uniform step size. For large injection rates, analytical expressions for the surface shear stresses in the longitudinal and rotating directions and the surface heat transfer are also obtained using an approximate method. For large injection rates, the surface heat transfer tends to zero, but the surface shear stresses in the longitudinal and rotating directions remain finite but small. The surface shear stresses and the surface heat transfer decrease with increasing rate of injection, but they increase with the magnetic field and the rotation parameter. The magnetic field or the rotation parameter induces an overshoot in the longitudinal velocity profile and the magnitude of the velocity overshoot increases significantly with the rotation parameters and the injection parameter. The location of the dividing streamline moves away from the boundary with increasing injection rate, but it moves towards the boundary with increasing magnetic and rotation parameters.
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Authors and Affiliations

Mahesh Kumari
Girishwar Nath
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Abstract

Confronted with a natural tendency of marginalization national/ethnic minorities and immigrant communities respond by adopting two diverse strategies of showing their presence in the public sphere of the host country. Depending on the level of their integration and the goals they want to achieve, they can either stress their links (affinity) with the majority culture or the differences that mark them out. However, some minority communities succeed in achieving a distinctive presence in the public sphere already at the stage of launching its own media.

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Authors and Affiliations

Krzysztof Wasilewski
ORCID: ORCID
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Abstract

The paper presents a simple method of measuring the luminous flux value dedicated to LED light sources. This method uses information about a spatial radiation pattern of the lighting source under test and the results of illuminance measurements at the axis of this source. The method is described and the results of the measurements obtained using this method and the classical method are compared and discussed. Tests have been carried out for LED modules of different geometries. The measurement error of the considered method is analysed.
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Authors and Affiliations

Krzysztof Górecki
1
ORCID: ORCID
Aleksandra Kalinowska
2
Przemysław Ptak
1
ORCID: ORCID

  1. Department of Marine Electronics, Gdynia Maritime University, ul. Morska 81-87, 81-225 Gdynia, Poland
  2. Faculty of Electrical Engineering, Gdynia Maritime University, ul. Morska 81-87, 81-225 Gdynia, Poland
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Abstract

Multiple Input Multiple Output (MIMO (techniques use multiple antennas at both transmitter and receiver for increasing the channel reliability and enhancing the spectral efficiency of wireless communication system.MIMO Spatial Multiplexing (SM) is a technology that can increase the channel capacity without additional spectral resources. The implementation of MIMO detection techniques become a difficult mission as the computational complexity increases with the number of transmitting antenna and constellation size. So designing detection techniques that can recover transmitted signals from Spatial Multiplexing (SM) MIMO with reduced complexity and high performance is challenging. In this survey, the general model of MIMO communication system is presented in addition to multiple MIMO Spatial Multiplexing (SM) detection techniques. These detection techniques are divided into different categories, such as linear detection, Non-linear detection and tree-search detection. Detailed discussions on the advantages and disadvantages of each detection algorithm are introduced. Hardware implementation of Sphere Decoder (SD) algorithm using VHDL/FPGA is also presented.

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Authors and Affiliations

Asma Mohamed
Abdel Halim Zekry
Reem Ibrahim
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Abstract

The changes in the paralinguistic (social, economic, cultural) and linguistic sphere influence the quantitative and qualitative changes in a categorically diversified onomastic resource and the communicative flow of its elements on three levels of linguistic contact — nationwide, local and individual. The flow is additionally determined in the sphere of spontaneous everyday communication and in higher communicative functions (official linguistic behaviour). The accumulation of determinants which allow the usage of appropriate names and appellative forms (official and unofficial, e.g. diminutives, feminisms) involves the application of cumulative research methods, including psycho-, socio- and pragmalinguistic description of proper names functioning in communication. The contemporary theory of discourse in its three dimensions — formal, functional and interactional gives this possibility. It also requires the constant specification and standardization of Neoslavonic onomastic terminology.

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Authors and Affiliations

Robert Mrózek
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Abstract

This article concerns the conditions for the institutionalization of open academic debate. The author focuses on the changes that have occurred over time in the seminar’s place in academic practice. She describes three types of seminars, from various eras in university history. In each case, the bases for the institutionalization of academic discussion were generally-held convictions as to what knowledge is and how it should be sought. Seminars legitimized academic debate. The examples provided—of the medieval university, Humboldt’s university, and the so-called entrepreneurial university—have various sources of legitimation: religion, the authority of scholarship, or the economic ‘usefulness’ of science (devoid of other authority). The author attempts to show that the sources of legitimation are reflected in the forms of the seminar’s institutionalization: the composition of the participants, the conversational rules (its public or closed character), and the transparency of academic knowledge.

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Authors and Affiliations

Dominika Michalak
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Abstract

In the paper we compare the geometric descriptions of the deformed sphere (i.e., the so-called λ-sphere) and the standard spheroid (namely, World Geodetic System 1984’s reference ellipsoid of revolution). Among the main geometric characteristics of those two surfaces of revolution embedded into the three-dimensional Euclidean space we consider the semi-major (equatorial) and semi-minor (polar) axes, quartermeridian length, surface area, volume, sphericity index, and tipping (bifurcation) point for geodesics. Next, the RMS (Root Mean Square) error is defined as the square-rooted arithmetic mean of the squared relative errors for the individual pairs of the discussed six main geometric characteristics. As a result of the process of minimization of the RMS error, we have obtained the proposition of the optimized value of the deformation parameter of the λ-sphere, for which we have calculated the absolute and relative errors for the individual pairs of the discussed main geometric characteristics of λ-sphere and standard spheroid (the relative errors are of the order of 10−6 – 10−9). Among others, it turns out that the value of the,sup> flattening factor of the spheroid is quite a good approximation for the corresponding value of the deformation parameter of the λ-sphere (the relative error is of the order of 10−4).
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Authors and Affiliations

Vasyl Kovalchuk
1
ORCID: ORCID
Ivaïlo M. Mladenov
2 3
ORCID: ORCID

  1. Institute of Fundamental Technological Research, Polish Academy of Sciences, Pawinskiego 5B, 02-106 Warsaw, Poland
  2. Institute of Mechanics, Bulgarian Academy of Sciences, Acad. G. Bonchev Str., Bl. 4, 1113 Sofia, Bulgaria
  3. Institute for Nuclear Research and Nuclear Energy, Bulgarian Academy of Sciences, Tsarigradsko Chaussee 72, 1784 Sofia, Bulgaria
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Abstract

This paper concerns the analytical investigation of the axisymmetric and steady flow of incompressible couple stress fluid through a rigid sphere embedded in a porous medium. In the porous region, the flow field is governed by Brinkman's equation. Here we consider uniform flow at a distance from the sphere. The boundary conditions applied on the surface of the sphere are the slip condition and zero couple stress. Analytical solution of the problem in the terms of stream function is presented by modified Bessel functions. The drag experienced by an incompressible couple stress fluid on the sphere within the porous medium is calculated. The effects of the slip parameter, the couple stress parameter, and permeability on the drag are represented graphically. Special cases of viscous flow through a sphere are obtained and the results are compared with earlier published results.
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Bibliography

[1] J. Bear. Dynamics of fluids in porous media. Courier Corporation, 2013.
[2] H.C. Brinkman. A calculation of the viscous force exerted by a flowing fluid on a dense swarm of particles. Flow, Turbulence and Combustion, 1(1):27–34, 1949. doi: 10.1007/bf02120313.
[3] R.H. Davis and H.A. Stone. Flow through beds of porous particles. Chemical Engineering Science, 48(23):3993–4005, 1993. doi: 10.1016/0009-2509(93)80378-4.
[4] B. Barman. Flow of a Newtonian fluid past an impervious sphere embedded in a porous medium. Indian Journal of Pure and Applied Mathematics, 27:1249–1256, 1996.
[5] I. Pop and D.B. Ingham. Flow past a sphere embedded in a porous medium based on the Brinkman model. International Communications in Heat and Mass Transfer, 23(6):865–874, 1996. doi: 10.1016/0735-1933(96)00069-3.
[6] D. Srinivasacharya and J.V. Ramana Murthy. Flow past an axisymmetric body embedded in a saturated porous medium. Comptes Rendus Mécanique, 330(6):417–423, 2002. doi: 10.1016/s1631-0721(02)01478-x.
[7] T. Grosan, A. Postelnicu, and I. Pop. Brinkman flowof a viscous fluid through a spherical porous medium embedded in another porous medium. Transport in Porous Media, 81(1):89–103, 2010. doi: 10.1007/s11242-009-9389-y.
[8] S. Deo and B.R. Gupta. Drag on a porous sphere embedded in another porous medium. Journal of Porous Media, 13(11):1009–1016, 2010. doi: 10.1615/JPorMedia.v13.i11.70.
[9] N.E. Leontev. Flow past a cylinder and a sphere in a porous medium within the framework of the Brinkman equation with the Navier boundary condition. Fluid Dynamics, 49(2):232–237, 2014. doi: 10.1134/S0015462814020112.
[10] S. El-Sapa. Effect of permeability of Brinkman flow on thermophoresis of a particle in a spherical cavity. European Journal of Mechanics-B/Fluids, 79:315–323, 2020. doi: 10.1016/j.euromechflu.2019.09.017.
[11] M.S. Faltas, H.H. Sherief, A.A. Allam, and B.A. Ahmed. Mobilities of a spherical particle straddling the interface of a semi-infinite Brinkman flow. Journal of Fluids Engineering, 143(7):071402, 2021. doi: 10.1115/1.4049931.
[12] M. Krishna Prasad and D. Srinivasacharya. Micropolar fluid flow through a cylinder and a sphere embedded in a porous medium. International Journal of Fluid Mechanics Research, 44(3):229–240, 2017. doi: 10.1615/InterJFluidMechRes.2017015283.
[13] B.R. Jaiswal. A non-Newtonian liquid sphere embedded in a polar fluid saturated porous medium: Stokes flow. Applied Mathematics and Computation, 316:488–503, 2018. doi: 10.1016/j.amc.2017.08.009.
[14] K. Ramalakshmi and P. Shukla. Drag on a fluid sphere embedded in a porous medium with solid core. International Journal of Fluid Mechanics Research, 46(3):219–228, 2019. doi: 10.1615/InterJFluidMechRes.2018025197.
[15] K.P. Madasu and T. Bucha. Influence of mhd on micropolar fluid flow past a sphere implanted in porous media. Indian Journal of Physics, 95(6):1175–1183, 2021. doi: 10.1007/s12648-020-01759-7.
[16] V.K. Stokes. Couple stresses in fluids. In Theories of Fluids with Microstructure, pages 34–80. Springer, 1966. doi: 10.1007/978-3-642-82351-0_4.
[17] V.K. Stokes. Theories of Fluids with Microstructure: An Introduction. Springer Science & Business Media, 2012. doi: 10.1007/978-3-642-82351-0.
[18] D. Pal, N. Rudraiah, and R. Devanathan. A couple stress model of blood flow in the microcirculation. Bulletin of Mathematical Biology, 50(4):329–344, 1988. doi: 10.1007/BF02459703.
[19] N.A. Khan, A. Mahmood, and A. Ara. Approximate solution of couple stress fluid with expanding or contracting porous channel. Engineering Computations, 30(3):399–408, 2013. doi: 10.1108/02644401311314358.
[20] D. Srinivasacharya and K. Kaladhar. Mixed convection flowof couple stress fluid in a non-Darcy porous medium with Soret and Dufour effects. Journal of Applied Science and Engineering, 15(4):415–422, 2012.
[21] M. Devakar, D. Sreenivasu, and B. Shankar. Analytical solutions of couple stress fluid flows with slip boundary conditions. Alexandria Engineering Journal, 53(3):723–730, 2014. doi: 10.1016/j.aej.2014.06.005.
[22] D. Srinivasacharya, N. Srinivasacharyulu, and O. Odelu. Flow of couple stress fluid between two parallel porous plates. International Journal of Applied Mathematics, 41(2).
[23] E.A. Ashmawy. Drag on a slip spherical particle moving in a couple stress fluid. Alexandria Engineering Journal, 55(2):1159–1164, 2016. doi: 10.1016/j.aej.2016.03.032.
[24] P. Aparna, P. Padmaja, N. Pothanna, and J.V. Ramana Murthy. Couple stress fluid flow due to slow steady oscillations of a permeable sphere. Nonlinear Engineering, 9(1):352–360, 2020. doi: 10.1515/nleng-2020-0021.
[25] S.O. Adesanya, S.O. Kareem, J.A. Falade, and S.A. Arekete. Entropy generation analysis for a reactive couple stress fluid flow through a channel saturated with porous material. Energy, 93:1239–1245, 2015. doi: 10.1016/j.energy.2015.09.115.
[26] A.R. Hassan. The entropy generation analysis of a reactive hydromagnetic couple stress fluid flow through a saturated porous channel. Applied Mathematics and Computation, 369:124843, 2020. doi: 10.1016/j.amc.2019.124843.
[27] S.I.Abdelsalam, J.X.Velasco-Hernández, and A.Z. Zaher. Electro-magnetically modulated selfpropulsion of swimming sperms via cervical canal. Biomechanics and Modeling in Mechanobiology, 20(3):861–878, 2021. doi: 10.1007/s10237-020-01407-3.
[28] M.M. Bhatti, S.Z. Alamri, R. Ellahi, and S.I. Abdelsalam. Intra-uterine particle–fluid motion through a compliant asymmetric tapered channel with heat transfer. Journal of Thermal Analysis and Calorimetry, 144(6):2259–2267, 2021. doi: 10.1007/s10973-020-10233-9.
[29] A.R. Hadjesfandiari and G.F. Dargush. Polar continuum mechanics. arXiv preprint arXiv:1009.3252, 2010.
[30] A.R. Hadjesfandiari and G.F. Dargush. Couple stress theory for solids. International Journal of Solids and Structures, 48(18):2496–2510, 2011. doi: 10.1016/j.ijsolstr.2011.05.002.
[31] A.R. Hadjesfandiari, G.F. Dargush, and A. Hajesfandiari. Consistent skew-symmetric couple stress theory for size-dependent creeping flow. Journal of Non-Newtonian Fluid Mechanics, 196:83–94, 2013. doi: 10.1016/j.jnnfm.2012.12.012.
[32] A.R. Hadjesfandiari, A. Hajesfandiari, and G.F. Dargush. Skew-symmetric couple-stress fluid mechanics. Acta Mechanica, 226(3):871–895, 2015. doi: 10.1007/s00707-014-1223-0.
[33] C.L.M.H. Navier. Mémoires de l’Académie Royale des Sciences de l’Institut de France. Royale des Sciences de l’Institut de France, 1823.
[34] I.M. Eldesoky, S.I. Abdelsalam, W.A. El-Askary, A.M. El-Refaey, and M.M. Ahmed. Joint effect of magnetic field and heat transfer on particulate fluid suspension in a catheterized wavy tube. BioNanoScience, 9(3):723–739, 2019. doi: >10.1007/s12668-019-00651-x.
[35] M.M. Bhatti and S.I. Abdelsalam. Thermodynamic entropy of a magnetized ree-eyring particle-fluid motion with irreversibility process: A mathematical paradigm. Journal of Applied Mathmatics nd Mechanics/Zeitschrift fur Angewandte Mathematik und Mechanik, 101(6):e202000186, 2021. doi: 10.1002/zamm.202000186.
[36] S. El-Sapa and N.S. Alsudais. Effect of magnetic field on the motion of two rigid spheres embedded in porous media with slip surfaces. The European Physical Journal E, 44(5):1–11, 2021. doi: 10.1140/epje/s10189-021-00073-2.
[37] K.P. Madasu, M. Kaur, and T. Bucha. Slow motion past a spheroid implanted in a Brinkman medium: Slip condition. International Journal of Applied and Computational Mathematics, 7(4):1–15, 2021. doi: 10.1007/s40819-021-01104-4.
[38] J. Happel and H. Brenner. Low Reynolds Number Hydrodynamics: with Special Applications to Particulate Media. Springer Science & Business Media, 2012.
[39] S. El-Sapa, E.I. Saad, and M.S. Faltas. Axisymmetric motion of two spherical particles in a brinkman medium with slip surfaces. European Journal of Mechanics-B/Fluids, 67:306–313, 2018. doi: 10.1016/j.euromechflu.2017.10.003.
[40] V.K. Stokes. Effects of couple stresses in fluids on the creeping flow past a sphere. The Physics of Fluids, 14(7):1580–1582, 1971. doi: 10.1063/1.1693645.
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Authors and Affiliations

Krishna Prasad Madasu
1
ORCID: ORCID
Priya Sarkar
1
ORCID: ORCID

  1. Department of Mathematics, National Institute of Technology, Raipur-492010, Chhattisgarh, India
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Abstract

The article considers Roman Ingarden’s fundamental questions in the context of the position called philosophical fundamentalism. It turns out that the defining feature of this position, i.e. the search for answers to the question about the conditions of validity of statements in the sphere of traditional branches of philosophy: ontology, epistemology, ethics and aesthetics, finds its counterpart in Ingarden’s ontological and epistemological assumptions in phenomenology. They guarantee the legitimacy of any other claims. Ingarden’s philosophical fundamentalism, considered here in relation to the work- ‑scheme, weakened with time, which seems to be evidenced by the author’s doubts as to the legitimacy of the existence of the sphere of ideal objects determining this work. It seems highly possible that this is Ingarden’s bow to culture, and to cultural and historical relativization of the unchanging sphere of ideal objects.
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Authors and Affiliations

Barbara Kotowa
1

  1. prof. em., Uniwersytet im. Adama Mickiewicza w Poznaniu, Wydział Filozoficzny, ul. Szamarzewskiego 89c, 60-568 Poznań

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