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Number of results: 10
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Abstract

According to Bell’s theorem, no local realistic model can reproduce all predictions of quantum mechanics for the EPR-B experiment. Any such model would have to predict both the perfect correlation and breaking the CHSH inequality, but this seems impossible, since to provide the first prediction, the model would have to be deterministic, whereas this would seem to make the second one impossible. A model of the EPR-B experiment is presented, in which this apparent contradiction is expected to be avoided due to a deterministic chaotic mechanism underlying measurements. The model is in the phase of a “black box” model, since this mechanism is not yet specified, but only a corresponding probabilistic response function.
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Authors and Affiliations

Jan Czerniawski
1

  1. Instytut Filozofii Uniwersytetu Jagiellońskiego
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Abstract

Prof. Przemysław Perlikowski, a mechanical engineer, and his wife Asst. Prof. Renata Perlikowska, who studies opioid peptides used in medicine, discuss the challenges of research work and life.

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Authors and Affiliations

Przemysław Perlikowski
ORCID: ORCID
Renata Perlikowska
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Abstract

The most important feature of bells is their sound. Their clarity and beauty depend, first of all, on the bell’s geometry - particularly the shape of its profile and the mechanical properties of alloy. Bells are the castings that work by emitting sound in as-cast state. Therefore all features that are created during melting, pouring, solidification and cooling processes will influence the bell's sound. The mechanical properties of bronze depend on the quality of alloy and microstructure which is created during solidification and depend on its kinetics. Hence, if the solidification parameters influence the alloy’s properties, how could they influence the frequencies of bell`s tone? Taking into account alterable thickness of bell's wall and differences in microstructure, the alloy's properties in bell could be important. In the article authors present the investigations conducted to determine the influence of cooling kinetics on microstructure of bronze with 20 weight % tin contents.

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Authors and Affiliations

D. Bartocha
C. Baron
J. Suchoń
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Abstract

The most important feature of bells is their sound. Its clarity and beauty depend, first of all, on the bell’s geometry - particularly the shape

of its profile, but also on the quality of alloy used to its cast. Hence, if the melting and pouring parameters could influence the alloy’s

properties, what influence they would have on the frequencies of bell’s tone. In the article authors present their own approaches to find

answers on that and more questions.

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Authors and Affiliations

D. Bartocha
C. Baron
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Abstract

The history of literature and art history were not included in the programme of my historical studies (1960–1965). Naturally, all history professors would usually include something about art and literature in their lectures on “their” historical period, but not as a key element. Efforts were made to separate history and belles‑lettres (in its various manifestations). A strongly positivist vision of research and transferring its results to the general public was cultivated – which had its advantages in the face of ideological pressure on science in the People's Republic of Poland. Today, the function of both historical sources and statements on history are frequently taken on by literature, which I define very broadly: literary texts (sometimes even of clearly inferior quality), political texts, diaries and journals, journalistic reports, petitions, defence speeches, sometimes letters. Also interesting for the historian is the route these texts take to the reading or listening public, as well as their reception, sometimes their renaissance after many years. There is no need to add that with such an approach, the people who are the authors of even outstanding historical works are not necessarily those who are professional historians.
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Authors and Affiliations

Marcin Kula
1
ORCID: ORCID

  1. Uniwersytet Warszawski (emeritus)
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Abstract

The aim of this paper is to present methods of digitally synthesising the sound generated by vibroacoustic systems with distributed parameters. A general algorithm was developed to synthesise the sounds of selected musical instruments with an axisymmetrical shape and impact excitation, i.e., Tibetan bowls and bells. A coupled mechanical-acoustic field described by partial differential equations was discretized by using the Finite Element Method (FEM) implemented in the ANSYS package. The presented synthesis method is original due to the fact that the determination of the system response in the time domain to the pulse (impact) excitation is based on the numerical calculation of the convolution of the forcing function and impulse response of the system. This was calculated as an inverse Fourier transform of the system’s spectral transfer function. The synthesiser allows for obtaining a sound signal with the assumed, expected parameters by tuning the resonance frequencies which exist in the spectrum of the generated sound. This is accomplished, basing on the Design of Experiment (DOE) theory, by creating a meta-model which contains information on its response surfaces regarding the influence of the design parameters. The synthesis resulted in a sound pressure signal in selected points in space surrounding the instrument which is consistent with the signal generated by the actual instruments, and the results obtained can improve them.
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Authors and Affiliations

Andrzej Gołaś
Roman Filipek
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Abstract

This paper introduces security assessment methodology for isolated single-workstation multilayer systems processing sensitive or classified data according with a corresponding security model for such system. The document provides a high-level tool for systematizing certain-class-systems security models development. The models based on the introduced methodology cover data confidentiality and availability attributes protection on a sufficient level.

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Authors and Affiliations

Daniel Wiechecki
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Abstract

The subject of the study was to determine the impact of changes in mechanical properties of high-tin bronzes on the basic components of the sound of a bell. Change in the tin concentration in the range of about 7.5 to 20 parts wt. in a casting alloy significantly affects the mechanical properties of the alloy such as Young’s modulus or hardness. The free vibrations of bells were obtained with the help of the finite element method. In the numerical analyses the mechanical properties of standard alloys were adopted. The obtained natural frequencies of the bell made of a bronze with different tin concentration in copper were compared with the acoustic properties of a real bell casted on the basis of the same ribs. A significant effect of the increase in the alloying share of tin on the obtained results was stated. In addition, the acoustic analysis of aluminum bronze C95500 have been performed. Based on the obtained results, authors stated that this material can replace the commonly used high tin bronze C91300 for the unit production of bells.
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Authors and Affiliations

D. Cekus
1
ORCID: ORCID
M. Nadolski
2
ORCID: ORCID

  1. Czestochowa University of Technology, Department of Mechanics and Machine Design Fundamentals, 73 Dąbrowskiego S tr., 42-201 Czestochowa, Poland
  2. Czestochowa University of Technology, Faculty of Production Engineering and Materials Technology, 19 Armii Krajowej Av., 42-200 Czestochowa, Poland
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Abstract

The work done in this study is a preliminary investigation into the possibility of modelling the filling and solidification process of castings in molds made with the additive method. The work originated from an experiment to produce a bronze casting with a high tin content in an additive mold. The mold filling and solidification simulation was carried out in the MAGMASO FT program, and the lambda thermal conductivity coefficient used in the program’s material database was corrected based on the actual temperature values of the printed form. The results were compared with the modeling results for the physical properties of furan molds based on the program database. The microstructure of the castings obtained in the compared forms was assessed.
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Authors and Affiliations

M. Nadolski
1
ORCID: ORCID
Ł. Bernat
2
D. Cekus
3
ORCID: ORCID
P. Kwiatoń
ORCID: ORCID
A. Pietrzak
4

  1. Czestochowa University of Technology, Faculty of Production Engineering and Materials, Department of Metallurgy and Metal Technology, 42-200 Czestochowa, Poland
  2. Poznan University of Technology, Faculty of Mechanical Engineering, Institute of Materials Technology, Division of Foundry and Plastic Working,60-965 Poznan, Poland
  3. Czestochowa University of Technology, Faculty of Mechanical Engineering and Computer Science, Department of Mechanics and Machine Design Fundamentals, 42-200 Czestoch owa, Poland
  4. AGH University of Kraków, Faculty of Foundry Engineering, Department of Foundry, Al . Mickiewicza 30, 30-059 Krakow, Poland
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Abstract

Underwater Acoustic Communications (UWAC) is an emerging technology in the field of underwater communications, and it is challenging because of the signal attenuation of the sound waves. Multiple Input and Multiple- Output (MIMO) is introduced in UWAC because of its support in enhancing the data throughput even under the conditions of interference, signal fading, and multipath. The paper presents the concept and analysis of 2× 2 MIMO UWAC systems that uses a 4- QAM spatial modulation scheme thus minimizing the decoding complexity and overcoming the Inter Channel Interference (IChI). Bit Error Rate (BER) investigation is carried out over different link distances under acoustic Line of Sight (LOS). The utilization of Zero Forcing (ZF) and Vertical-Bell Laboratories Layered Space-Time (VBLAST) equalizers, which estimates the transmitted data proves a success of removing Inter Symbol Interference (ISI). The ISI caused due to multipath effect and scattering in UWAC can be reduced by iterative process considered in VBLAST. A study is made on how the distance between the transmitter and the receiver and the Doppler Effect has its impact on the performance of the system.

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Authors and Affiliations

B. Pranitha
L. Anjaneyulu
Hoa Le Minh
Nauman Aslam
V. Sandeep Kumar

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