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Number of results: 4
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Abstract

Amount of works and activities tending towards defining new transport mode on the basis of the hyperloop system concept is growing significantly. They assume use of individual vehicles, offering space for several dozen passengers, running with speeds near speed of sound in a closed space with significantly lowered air pressure, utilizing magnetic levitation. Simultaneously it is fairly from economic point of view assumed, that first implementations should link locations between which traffic demand is expected to be very high. Assumed short spacing between hyper-vehicles, which are frequently declared to be ad-hoc adjusted to transport demand, to the knowledge of the authors gained in railway transport, seems to be in conflict with high speed safety related spacing in view of the line infrastructure capacity operational rules defined in the UIC (International Union of Railways) documents. That is the challenge, that formed the basis for authors’ investigations described in the paper. Several thesis regarding future new mode of transport based on hyperloop concept form an outcome of those investigations presented in conclusions.
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Authors and Affiliations

Marek Pawlik
1
ORCID: ORCID
Magdalena Kycko
2
ORCID: ORCID
Konrad Zakrzewski
2
ORCID: ORCID

  1. Assistant professor, PhD., Eng., Warsaw University of Technology, Faculty of Civil Engineering, al. Armii Ludowej 16, 00-637 Warsaw, Poland
  2. M.Sc., Eng., Railway Research Institute, Chłopickiego 50, 04-275 Warsaw, Poland
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Abstract

The article presents the prototype of a measurement system with a hot probe, designed for testing thermal parameters of heat insulation materials. The idea is to determine parameters of thermal insulation materials using a hot probe with an auxiliary thermometer and a trained artificial neural network. The network is trained on data extracted from a nonstationary two-dimensional model of heat conduction inside a sample of material with the hot probe and the auxiliary thermometer. The significant heat capacity of the probe handle is taken into account in the model. The finite element method (FEM) is applied to solve the system of partial differential equations describing the model. An artificial neural network (ANN) is used to estimate coefficients of the inverse heat conduction problem for a solid. The network determines values of the effective thermal conductivity and effective thermal diffusivity on the basis of temperature responses of the hot probe and the auxiliary thermometer. All calculations, like FEM, training and testing processes, were conducted in the MATLAB environment. Experimental results are also presented. The proposed measurement system for parameter testing is suitable for temporary measurements in a building site or factory.

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Authors and Affiliations

Stanisław Chudzik
Waldemar Minkina
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Abstract

The proper designing of PV systems requires the use of advanced building energy simulation techniques. It allows to design the best position of the PV array, as well as the right quantity of produced energy in different cases. On the other hand the PV efficiency is not only a constant value but changes according to temperature and solar radiation. This paper is devoted to estimate the simultaneous effect of both weather factors on PV efficiency. The task was achieved by numerical simulation and ESP-r software. Computer simulations have been carried out with the use of the Typical Meteorological Year data for Warsaw (52°N 21°E). The greatest influence of temperature on the efficiency of solar energy conversion was observed for crystalline silicon cells. The influence of the boundary conditions assumed in the study is ignored for amorphous silicon cells in the summer period and regardless of the material type in the winter period.

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Authors and Affiliations

D. Heim
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Abstract

This article deals with the American chapter (World War II) in the lives of three Polish poets, Julian Tuwim, Kazimierz Wierzyński and Jan Lechoń, shown through the eyes of their fourth friend Józef Wittlin and his wife Halina, who spent the rest of their lives in the USA. The article is based on archival materials, most of which in the collections of Houghton Library.
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Authors and Affiliations

Jacek Hajduk
1
ORCID: ORCID

  1. Instytut Filologii Klasycznej UJ

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