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Number of results: 169
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Abstract

The market of consumer goods requires nowadays quick response to customer needs. As a consequence, this is transferred to the time restrictions that the semi-finished product manufacturer must meet. Therefore the cost of manufacturing cannot determine how production processes are designed, and the main evaluation function of manufacturing processes is the response time to customers’ orders. One of the ideas for implementing this idea is the QRM (Quick Response Manufacturing) production organization system. The purpose of the research undertaken by the authors was to develop an innovative solution in the field of production structure, allowing for the implementation of the QRM concept in a Contract Manufacturer, which realizes its tasks according to engineering-to-order (ETO) system in conditions defined as High Mix, Low Volume, High Complexity. The object of the research was to select appropriate methods for grouping products assuming that certain operations will be carried out in traditional but well-organized technological and/or linear cells. The research was carried out in one of the largest producers of sheet metal components in Europe. Pre-completed groupings for data obtained from the company had indicated that – among the classical methods – the best results had been given by the following methods: King’s Algorithm (otherwise called: Binary Ordering, Rank Order Clustering), k-means, and Kohonen’s neural networks. The results of the tests and preliminary simulations based on the data from the company proved that the implementation of the QRM concept does not have to be associated with the absolute formation of multi-purpose cells. It turned out that the effect of reducing the response time to customer needs can be obtained by using hybrid structures that combine solutions characteristic of cellular systems with traditional systems such as a technological, linear, or mixed structure. However, this requires the application of technological solutions with the highest level of organization.
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Authors and Affiliations

Jerzy Duda
1
Andrzej Macioł
2
Stanisław Jedrusik
2
Bogdan Rebiasz
2
A. Stawowy
ORCID: ORCID
Monika Sopinska-Lenart
3
Adam Stawowy
2

  1. AGH University of Science and Technology, Faculty of Management, Kraków, Poland
  2. AGH University of Science and Technology, Faculty of Management, Kraków, Poland
  3. Addit Sp. z o.o., Wegrow, Poland
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Abstract

The paper presents selected aspects of dynamic numerical simulations of an orthotropic steel railway bridge loaded by high-speed trains. The model of moving loads was adopted in accordance with the models set out in the applicable standards. The current European code requirements are referred in which the computer calculations of the dynamic response of the structure are the basis for assessing the suitability of the structure to carry high-speed rail traffic ( v > 160 km/h ). In this research the calculations are based on the author's method of generating traffic roads in Abaqus FEM environment. lt is emphasized in the paper that in most commercial FEM codes (including Abaqus), moving loads are not implemented in modules responsible for defining of loads. The author's approach to this issue allowed to obtain results confirming its adequacy. In the longer term, the authors will develop a plan to adapt this algorithm in order to generale traftic loads on bridges discretized as spatial and plane numerical models.

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Authors and Affiliations

A. Zbiciak
R. Oleszek
R. Michalczyk
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Abstract

Considering concrete nonlinearity, the wave height limit between small and large amplitude sloshing is defined based on the Bernoulli equation. Based on Navier-Stokes equations, the mathematical model of large amplitude sloshing is established for a Concrete Rectangle Liquid-Storage Structure (CRLSS). The results show that the seismic response of a CRLSS increases with the increase of seismic intensity. Under different seismic fortification intensities, the change in trend of wave height, wallboard displacement, and stress are the same, but the amplitudes are not. The areas of stress concentration appear mainly at the connections between the wallboards, and the connections between the wallboard and the bottom.

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Authors and Affiliations

X. Cheng
D. Li
P. Li
X. Zhang
G. Li
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Abstract

This paper presents an approach based on NURBS (non-uniform rational B-splines) to achieve a seismic response surface (SRS) from a group of points obtained by using an analytical model of RC joints. NURBS based on the genetic algorithm is an important mathematical tool and consists of generalizations of Bezier curves and surfaces and B-splines. Generally, the accuracy of the design process of joints depends on the number of control points that are captured in the results of experimental research on real specimens. The values obtained from the specimens are the best tools to use in seismic analysis, though more expensive when compared to values simulated by SRSs. The SRS proposed in this paper can be applied to obtain surfaces that show site effect results on destructions of beam-column joint, taking into account different site conditions for a specific earthquake. The efficiency of this approach is demonstrated by the retrieval of simulated-versus-analytical results.

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Authors and Affiliations

R. Tabatabaei Mirhosseini
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Abstract

Considering responsibility as a key anthropological category, Roman Ingarden stresses that it could only be inquired through the lens of a subject that is perceived personally, and not as a ‘pure I’. On the one hand, responsibility determines the nature of personal existence, and on the other hand, personal existence constitutes a space for interrogating about any meanings of the concept of responsibility. What remains problematic, however, is an alternative outlined by Ingarden, which implies that perception of a personal subject must be conducted within either of two perspectives – one that refers to a substantial model of personal subject, or the other that relates to acts of actualising the subject, which unfold in the stream of consciousness. It seems possible to go beyond this contradiction and reconcile the two perspectives – which the modern philosophy of dialogue proposes to do. Ingarden emphasises that the analysis of the concept of responsibility should not be limited to the realm of morality. However, all four scenarios that the philosopher uses as research fields to scrutinise the concept point, or at least imply the necessity of including aesthetic issues. Furthermore, the four fields of analysis – when somebody 1) bears responsibility, 2) takes responsibility, 3) is held responsible, and 4) acts responsibly – should not be perceived as isolated from one another. The link between them is man, who appears as a person in certain situations, while in others, his personal status is unrevealed, although it still remains within a firm horizon of situations and meanings examined herein. Moreover, regardless of the polarisation of the research fields highlighted by Ingarden, moral context constitutes a permanent space of reference for a human person, who not only asks for the sense (meanings) of responsibility, but also determines his/her personal existence through meanings and with their help.
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Authors and Affiliations

Witold P. Glinkowski
1
ORCID: ORCID

  1. Uniwersytet Łódzki, Instytut Filozofii, ul. Lindleya 3/5, 90-131 Łódź
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Abstract

The growing popularity of so-called cognitive enhancement technologies raises questions about their impact on the sphere of individual legal responsibility. This article examines the issue of whether, in a situation where a surgeon, prone to making a fatigue-related medical error, refuses to undergo a safe cognitive enhancement before surgery, the surgeon can be attributed liability for damages. The answer to this question is negative, however, as indicated in the article, the impossibility of attributing damages is a result of (1) the lack of professional guidelines requiring doctors to undergo cognitive enhancement; (2) the lack of scientific evidence that the use of such measures results in the elimination of fatigue and reduces the risk of error. As a result, the negative answer to the analyzed question is not determined by the solution of the model of liability for damages adopted in Polish law, but rather by the current state of research on cognitive improvement. This gives the analysis a universal character and makes it possible to relate the method adopted in it to new results of research on means of cognitive enhancement if any.

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Authors and Affiliations

Andrzej Girdwoyń
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Abstract

Psychoacoustics is traditionally based on a world model that assumes a physical world existing independently of any observer - the so-called objective world. Being exposed to this world, an observer is impinged upon by a variety of stimuli reaching his/her sensory organs. These stimuli, if physiologically adequate, may cause biological transduction and signal processing in the sensory organs and its afferent pathways in such a way that finally a specific excitation of the cortex takes place, which results in sen-sations to appear in the observer’s perceptual world. The sensations are understood as being subjective, since they require an observer to exist. This world model - also known as (objectivistic) realism - reaches its limits when it comes to explaining more complex phenomena of perception. Thereupon, in this paper, an alternative world model is emphasized and applied to psychoacoustics, namely the perceptionist’s model. Like realism, perceptionism has a long tradition in epistemology. It appears to be suitable to improve our understanding of perceptual organization.

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Authors and Affiliations

Jens Blauert
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Abstract

Simultaneous propagation of vibrations and noise has an important role in the task of minimizing vibroacoustic hazards on the station of operator of the construction machinery. In many cases vibrations transferred by the construction are processed to noise in different points of the machine. As a result, they may increase the level of noise at the workplace. The paper presents the proposition of a simple estimation of noise and vibration propagation paths of the machine. On the basis of the analysis of hydraulic excavator an effectiveness of a proposed procedure was shown. This procedure helps to minimize the transfer of vibrations of power unit in selected frequency ranges which led to the change of overall noise level in operator’s cab about 5 dB.
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Authors and Affiliations

Zbigniew Dąbrowski
Jacek Dziurdź
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Abstract

When two pure tones of slightly different frequency are presented separately to each ear, the listener perceives a third single tone with amplitude variations at a frequency that equals the difference between the two tones; this perceptual illusion is known as the binaural auditory beat (BB). There are anecdotal reports that suggest that the binaural beat can entrain EEG activity and may affect the arousal levels, although few studies have been published. There is a need for double-blind, well-designed studies in order to establish a solid foundation for these sounds, as most of the documented benefits come from self-reported cases that could be affected by placebo effect. As BBs are a cheap technology (it even exists a free open source programmable binaural- beat generator on the Internet named Gnaural), any achievement in this area could be of public interest. The aim in our research was to explore the potential of BBs in a particular field: tasks that require focus and concentration. In order to detect changes in the brain waves that could relate to any particular improvement, EEG recordings of a small sample of individuals were also obtained. In this study we compare the effect of different binaural stimulation in 7 EEG frequency ranges. 78 participants were exposed to 20-min binaural beat stimulation. The effects were obtained both quali- tative with cognitive test and quantitative with EEG analysis. Results suggest no significant statistical improvement in 20-min stimulation.
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Authors and Affiliations

Adela Crespo
Manuel Recuero
Gerardo Galvez
Adrián Begoña
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Abstract

The phenolic compounds are known as priority pollutants, even in low concentrations, as a result of their toxicity and non-biodegradability. For this reason, strict standards have been established for them. In addition, chlorophenols are placed in the 38th to 43th in highest priority order of toxic pollutants. As a consequence, contaminated water or wastewaters with phenolic compounds have to be treated before discharging into the receiving water. In this study, Response Surface Methodology (RSM) has been used in order to optimize the effect of main operational variables responsible for the higher 4-chlorophenol removal by Activated Carbon-Supported Nanoscale Zero Valent Iron (AC/NZVI). A Box-Behnken factorial Design (BBD) with three levels was applied to optimize the initial concentration, time, pH, and adsorbent dose. The characterization of adsorbents was conducted by using SEM-EDS and XRD analyses. Furthermore, the adsorption isotherm and kinetics of 4-chlorophenol on AC and AC/NZVI under various conditions were studied. The model anticipated 100% removal efficiency for AC/NZVI at the optimum concentration (5.48 mg 4-chlorophenol/L), pH (5.44), contact time (44.7 min) and dose (0.65g/L). Analysis of the response surface quadratic model signified that the experiments are accurate and the model is highly significant. Moreover, the synthetic adsorbent is highly efficient in removing of 4-chlorophenol.

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Authors and Affiliations

Monireh Majlesi
Yalda Hashempour
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Abstract

This research was conducted to study the adsorption of ammonium ions onto pumice as a natural and low-cost adsorbent. The physico-chemical properties of the pumice granular were characterized by X-ray diffraction (XRD), Fourier transforms infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). Modeling and optimization of a NH4+ sorption process was accomplished by varying four independent parameters (pumice dosage, initial ammonium ion concentration, mixing rate and contact time) using a central composite design (CCD) under response surface methodology (RSM). The optimum conditions for maximum removal of NH4+ (70.3%) were found to be 100 g, 20 mg/l, 300 rpm and 180 min, for pumice dosage, initial NH4+ ion concentration, mixing rate and contact time. It was found that the NH4+ adsorption on the pumice granular was dependent on adsorbent dosage and initial ammonium ion concentration. NH4+ was increased due to decrease the initial concentration of NH4 and increase the contact time, mixing rate and amount of adsorbent.

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Authors and Affiliations

Masoud Moradi
Mehdi Fazlzadehdavil
Meghdad Pirsaheb
Yadollah Mansouri
Touba Khosravi
Kiomars Sharafi
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Abstract

Incomplete oxygen reduction gives rise to reactive oxygen species (ROS). For a long time they have been considered unwelcome companions of aerobic metabolism. Organisms using oxygen developed several systems of ROS scavenging with enzymatic and non enzymatic antioxidants, which allow them control the cellular level of oxygen derived from free radicals. It is well established nowadays that ROS are not necessarily negative byproducts, but they also play an important role in cellular mechanisms. They are involved in many regular cellular processes in all aerobic organisms. When the antioxidant system is overcome and the balance between ROS production and scavenging is disrupted, oxidative stress occurs. It has been reported that oxidative stress may be linked to some human diseases and is also involved in biotic and abiotic stress response in plants.

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Authors and Affiliations

Tomasz Twardowski
Dorota Gurda
Anna M. Kietrys
Aleksandra Szopa
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Abstract

In this work we report simulation and experimental results for an MWIR HgCdTe photodetector designed by computer simulation and fabricated in a joint laboratory run by VIGO Sytems S.A. and Military University of Technology. The device is based on a modified N+pP+ heterostructure grown on 2”., epiready, semi-insulating (100) GaAs substrates in a horizontal MOCVD AIX 200 reactor.

The devices were examined by measurements of spectral and time responses as a function of a bias voltage and operating temperatures. The time response was measured with an Optical Parametric Oscillator (OPO) as the source of ~25 ps pulses of infrared radiation, tuneable in a 1.55–16 μm spectral range. Two-stage Peltier cooled devices (230 K) with a 4.1 μm cut-off wavelength were characterized by 1.6 × 1012 cm Hz1/2/W peak detectivity and < 1 ns time constant for V > 500 mV.

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Authors and Affiliations

Kacper Grodecki
Piotr Martyniuk
Małgorzata Kopytko
Andrzej Kowalewski
Dawid Stępień
Artur Kębłowski
Adam Piotrowski
Józef Piotrowski
Waldemar Gawron
Antoni Rogalski
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Abstract

In this work, an approach to the design of broadband thickness-mode piezoelectric transducer is pre- sented. In this approach, simulation of discrete time model of the impulse response of matched and backed piezoelectric transducer is used to design high sensitivity, broad bandwidth, and short-duration impulse response transducers. The effect of matching the performance of transmitting and receiving air backed PZT-5A transducer working into water load is studied. The optimum acoustical characteristics of the quarter wavelength matching layers are determined by a compromise between sensitivity and pulse duration. The thickness of bonding layers is smaller than that of the quarter wavelength matching layers so that they do not change the resonance peak significantly. Our calculations show that the −3 dB air backed transducer bandwidth can be improved considerably by using quarter wavelength matching layers. The computer model developed in this work to predict the behavior of multilayer structures driven by a transient waveform agrees well with measured results. Furthermore, the advantage of this this model over other approaches is that the time signal for optimum set of matching layers can be predicted rapidly
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Authors and Affiliations

Mohamed G.S. Ali
Nour Z. Elsayed
Ebtsam A. Eid
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Abstract

A new method for determining optimum dimension ratios for small rectangular rooms has been presented. In a theoretical model, an exact description of the room impulse response was used. Based on the impulse response, a frequency response of a room was calculated to find changes in the sound pressure level over the frequency range 20–200 Hz. These changes depend on the source and receiver positions, thus, a new metric equivalent to an average frequency response was introduced to quantify the overall sound pressure variation within the room for a selected source position. A numerical procedure was employed to seek a minimum value of the deviation of the sound pressure level response from a smooth fitted response determined by the quadratic polynomial regression. The most smooth frequency responses were obtained when the source was located at one of the eight corners of a room. Thus, to find the best possible dimension ratios, in the numerical procedure the optimal source position was assumed. Calculation results have shown that optimum dimension ratios depend on the room volume and the sound damping inside a room, and for small and medium volumes these ratios are roughly 1 : 1.48 : 2.12, 1 : 1.4 : 1.89 and 1 : 1.2 : 1.45. When the room volume was suitably large, the ratio 1 : 1.2 : 1.44 was found to be the best one.
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Authors and Affiliations

Mirosław Meissner
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Abstract

In this paper a concept of finite impulse response (FIR) narrow band-stop (notch) filter with non-zero initial conditions, based on infinite impulse response (IIR) prototype filter, is proposed. The filter described in this paper is used to suppress power line noise from ECG signals. In order to reduce the transient response of the proposed FIR notch filter, optimal initial conditions for the filter have been determined. The algorithm for finding the length of the initial conditions vector is presented. The proposed values of the length of initial conditions vector, for several ECG signals and interfering frequencies, are calculated. The proposed filters are tested using various ECG signals. Computer simulations demonstrate that the proposed FIR filters outperform traditional FIR filters with initial conditions set to zero.

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Authors and Affiliations

Sławomir Kocoń
Jacek Piskorowski
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Abstract

In this article, we present a comprehensive measurement system to determine the level of user emotional arousal by the analysis of electrodermal activity (EDA). A number of EDA measurements were collected, while emotions were elicited using specially selected movie sequences. Data collected from 16 participants of the experiment, in conjunction with those from personal questionnaires, were used to determine a large number of 20 features of the EDA, to assess the emotional state of a user. Feature selection was performed using signal processing and analysis methods, while considering user declarations. The suitability of the designed system for detecting the level of emotional arousal was fully confirmed, throughout the number of experiments. The average classification accuracy for two classes of the least and the most stimulating movies varies within the range of 61‒72%.

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Authors and Affiliations

M. Kołodziej
P. Tarnowski
A. Majkowski
R.J. Rak
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Abstract

The aim of the article is to show the dependence of what is our/mine and Other/Alien in thinking about conflicts around investment projects. Investments related to the development of space and resources of the Earth, especially if they cause any (real or potential) changes, generate negative emotions which often become the embers of conflict.

Paradoxically, participation in such conflict may benefit the parties involved. Positive outcomes include: meeting needs (attention and significance), fulfilling (new) social roles, learning about other points of view, finding themselves in new social groups or embedded in local communities. Living in the social theater of life, each person plays different roles, which can lead to tension and a sense of ambivalence. In this situation, the individual has a sense of identity dispersion, being able to be simultaneously in several groups opposing each other. The conflict surrounding the Orzesze mining project can serve as an example here. This and other examples show that what is mine and the Other/Alien, with all its separateness, is, however, more or less intertwined with each other. So, the phenomenon of mutual dependence between the Other/Alien and conflict can provide an interesting perspective when looking at conflicts in managing the space and resources of the Earth. Conflicts, in particular mining-related ones, are an extremely complex phenomenon with great potential – both negative and positive. The appreciation of the benefits mentioned in the article, which result from the mutual dependence of the parties involved in the conflict along with their readiness to go outside their comfort zones, provide an opportunity for mutual understanding and reaching agreement which could lead to a positive change consistent with the idea of sustainable development.

In this complex situation, the incorporation of not only sociological but also psychological aspects becomes an important element of the states’ and companies’ resources policy and cannot be neglected any more.

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Authors and Affiliations

Joanna Iza Belzyt
Jarosław Badera
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Abstract

In a television, obtaining a good acoustic response is a challenging issue because of slim mechanical structures. The area dedicated for speaker’s placement is limited and inadequate space inside the cabinet of a TV prevents possible solutions to increase the sound performance. In addition, frame of the TV’s is getting narrower as the customers searching for the highest screen to body ratio. These designing aspects restrain optimal speaker positioning to achieve good sound performance. In this paper, an analysis related to speaker’s placement and mounting angle is proposed. A rotation setup compatible with a TV was prepared to measure different facing position of the speaker. This paper proposes the analysis of speaker’s rotation and facing direction in a flat panel television and its effects on sound pressure level together with deviation of the acoustic response. Measurement results are analyzed with an audio analyzer together with a statistics tool to achieve precise results.
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Authors and Affiliations

Ibrahim Demirel
1

  1. Arçelik AS., Electronics HW Design, Turkey
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Abstract

The relative relationships “yield – evapotranspiration” were used long time ago. The well known linear relationship yi = 1 – ky (1 – ei), where yi is relative yield, ky – yield response factor and ei – relative evapotranspiration was proposed. It’s usually assumed that ky is constant for a given crop and climatic conditions. It was found, however, that ky for late variety of maize H 708 varied through the study years (1984–1990) in the Plovdiv region (South Bulgaria, altitude 150 m). During the dry years it was significantly higher than in the medium and humid years. The range of ky for maize in this location was 1.12–1.90, the average value being 1.50. The climate in the Sofia region (the ex-perimental field of Chelopechene, altitude 550 m) is comparatively more humid. The two regions approximately outlined the boundaries of the appropriate economical conditions for grain maize pro-duction. The experiments in the Sofia region were carried out in the years 1994–2000. The seven years results for mean variety maize showed that the relationships “yield – evapotranspiration” and, respectively, ky varied at these climatic conditions too. The highest ky value was 1.41 for the driest year (2000) and the lowest value – 1.05 for the most wet years (1995, 1999). The value of ky for av-erage years was 1.21. The yield response factor ky is of more significance when the relative evapotranspiration is less than 0.7–0.8. Thus, the extreme or the average values of ky could be used for the corresponding climatic regions. The relationships between ky and relative yield were estab-lished without considering irrigation.

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Authors and Affiliations

Bojidara Mladenova
Ivan Varlev
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Abstract

Karl Marx (and also Friedrich Engels, by the way) was – contrary to his own opinion – an author of several utopias which played a role in the 20th century. The question (which is of both historical-philosophical and historical-empirical character) therefore arises how important this role was. The author focuses on the characteristics of Marxian utopias, and specifically – on their axiological content and current relevance. According to the author, Marx’s utopias can be a convenient starting point for searching for various projects (political, economic, technological etc.) necessary to cope with global challenges that mankind faces in our time. The author is also considering Marx’s motives for a critical approach to utopias and points to those of them which in his opinion should be accepted, while distinguishing them from others which should be rejected.

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Authors and Affiliations

Waldemar Czajkowski

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