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Abstract

Small construction objects are often built by standard task teams. The problem is, how to allocate these teams to individual works? To solve the problem of allocation three methods have been developed. The first method allows to designate optimal allocation of teams to the individual works in deterministic conditions of implementation. As a criterion of the optimal allocation can be applied: “the minimization of time” or “the minimization of costs” of works execution. The second method has been developed analogously for both criteria but for stochastic conditions and for the stochastic data. The third method allows to appoint a compromise allocation of teams. In this case, the criteria “the minimization of time” and “the minimization of costs” are considered simultaneously. The method can be applied in deterministic or stochastic conditions of works implementation. The solutions of the allocation problems which have been described allow to designate the optimal allocation of task teams and to determine the schedule and cost of works execution.

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Authors and Affiliations

T. Kasprowicz
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Abstract

This paper presents a 3D finite element analysis of the effect caused by a blast inside a reinforced concrete tunnel. The simulated explosion was caused by the crash of a heavy vehicle transporting inflammable material (LPG). The finite element technique was used to analyze the structural problems on the tunnel reinforced concrete structure considering the fire action and the subsequent explosion (blast) effect, incorporating appropriate material models.
Through FEM software the tunnel behavior was described with regard to structural safety. Indeed, tunnels must be designed to withstand damage factors, so it is desirable that if such an explosion did occur, the tunnel should be able to return to service in safety as soon as possible with minor repairs. Therefore, following the presented analysis, the most important factors influencing the dynamic response and the damage of the structure could be identified. The simulation involved aspects of thermal analysis and structural problems and the tensions in the structure generated by the effect of temperature caused by the fire and by the blast overpressure were analyzed. Following this approach, the most important factors influencing the dynamic response and damage of structure can be identified and appropriate preventive measures can be designated.
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Bibliography

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Authors and Affiliations

Giovanni Leonardi
1
ORCID: ORCID
Rocco Palamara
1
ORCID: ORCID
Federica Suraci
1
ORCID: ORCID

  1. Department of Civil, Energy, Environmental and Materials Engineering, University of Reggio Calabria, Via Graziella, Reggio Calabria, Italy
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Abstract

In his A Theory of Justice John Rawls presents a critique of utilitarianism. He focuses on utilitarianism in the version offered by John Stuart Mill, but Rawls’s analysis of Mill’s views is schematic and limited to Mill’s ethical theory. Rawls does not recognize the importance of perfectionistic themes in Mill’s theory, nor does he note the consequences of that issue for the problem of gender equality. Rawls discuses those themes in his Lectures on the History of Political Philosophy. If one is primarily guided by Rawls’s A Theory of Justice, however, the person will be unable to appreciate similarities between Rawls’s and Mill’s positions. When focusing on the Lectures it is possible to recognize these affinities that are only dimly insinuated in A Theory of Justice. In the later volume they are strong enough to support the claim that a more pronounced affinity may bind these two authors that are not obvious at the first glance. I proceed therefore (1) to expose some shortcomings in the presentation of Mill’s utilitarianism by Rawls; (2) go on to analyse Lectures on the History of Political Philosophy in order to present a more penetrating reading of Mill’s utilitarianism by including its perfectionistic content; and (3) finally on the basis of those claims I point to some practical consequences of Mill’s and Rawls’s views on gender equality.
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Bibliography

Barker Ch. (2015), JS Mill on Nineteenth Century Marriage and the Common Law, „Law, Culture, and Humanities” 15 (1), s. 1–21.
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Donner W. (2005), John Stuart Mill’s Liberal Feminism, w: M.H. Morales (red.), Mill’s „The Subjection of Women”: Critical Essays, Lanham: Rowman & Littlefield Publishers, s. 1–12.
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Authors and Affiliations

Elżbieta Filipow
1
ORCID: ORCID

  1. Uniwersytet Warszawski, Wydział Filozofii, ul. Krakowskie Przedmieście 3, 00‑927 Warszawa
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Abstract

Electro-dynamic passive magnetic bearings are now viewed as a feasible option when looking for support for high-speed rotors. Nevertheless, because of the skew-symmetrical visco-elastic properties of such bearings, they are prone to operational instability. In order to avoid this, the paper proposes the addition of external damping into the newly designed vibrating laboratory rotor-shaft system. This may be achieved by means of using simple passive dampers that would be found among the components of the electro-dynamic bearing housings along with magnetic dampers, which satisfy the operational principles of active magnetic bearings. Theoretical investigations are going to be conducted by means of a structural computer model of the rotor-shaft under construction, which will take into consideration its actual dimensions and material properties. The additional damping magnitudes required to stabilize the most sensitive lateral eigenmodes of the object under consideration have been determined by means of the Routh-Hurwitz stability criterion.

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Authors and Affiliations

T. Szolc
F. Falkowski
M. Henzel
P. Kurnyta-Mazurek
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Abstract

W roku 1887 Henryk Siemiradzki namalował obraz zatytułowany Chopin w salonie księcia Antoniego Radziwiłła w roku 1829. Obraz przedstawia scenę, w której gry Chopina słuchają członkowie rodziny książęcej oraz zaproszeni goście, wśród których znajduje się znany badacz przyrody Alexander von Humboldt. Siemiradzki opracował kompozycję obrazu na podstawie tekstu poznańskiego nauczyciela Marcelego Antoniego Szulca z roku 1873. Jednakże tekst Szulca jest autoryzowanym tłumaczeniem opowiadania napisanego przez niemiecką pisarkę Elise Polko w roku 1868. Obraz Siemiradzkiego był pokazywany w niektórych krajach europejskich w latach 1887–1892. W następnych latach znane były tylko kopie jego fotograwiury. Przez 106 lat obraz był uważany za zaginiony, aż pojawił się ponownie w roku 1998 w Nowym Jorku. Przeprowadzono analizę biograficzną okresów, w których Chopin, Humboldt i Radziwiłł mogli się spotkać jednocześnie. Jako miejsca spotkania tych osób rozpatrzono rezydencje księcia Radziwiłła w Berlinie, Poznaniu i Antoninie oraz Warszawę.
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Authors and Affiliations

Andrzej B. Więckowski
1

  1. Instytut Fizyki, Wydział Fizykii Astronomii, Uniwersytet Zielonogórski, Zielona Góra; Instytut Fizyki Molekularnej PAN,Poznań

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