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Number of results: 80
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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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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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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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Abstract

The number of human cases of salmonellosis in the EU was 94,625 in 2015. Considering the source of these infections, Salmonella spp. was most frequently detected in broiler chicken meat and Salmonella Enteritidis (SE) was the most commonly reported serovar. The efficacy of probiotics in limiting Salmonella spp. infection in poultry has been demonstrated in numerous papers. The administration of probiotics at the level of primary production reduces the risk of contamination of poultry food products with Salmonella spp. A study was carried out in order to determine the potential for reducing the Salmonella spp. population in broiler chickens with the use of the Lavipan (JHJ, Poland) probiotic that comprised selected stains of lactic acid bacteria and Saccharomyces cervisae. Salmonella spp.-free broiler chickens were divided into two groups and received the same feed with (group L) or without (group C) the probiotic throughout the experiment. All day-old chickens were infected per os with SE. Samples of cecum content were collected 2, 4, and 6 weeks after SE infection and pectoral muscles were collected 6 weeks following SE infection for the evaluation of the SE population number. Serum samples for serological examinations were collected 6 weeks after infection. Six weeks after infection, the number of SE-positive cecal samples was lower in the L group (12.5% positive) in comparison to the C group (87.5%). Similar results were demonstrated for the muscle samples (25% in contrast to 87.5%). At the same time, in both cases, the SE CFU/g was significantly lower in the L group. The results of our study indicate that Lavipan was capable of reducing the population of SE in the gastrointestinal tract, which eventually improved the hygienic parameters of the pectoral muscles. Four weeks after infection, SE was not detected in any of the experimental groups. In both groups, no specific anti-SE antibodies were detected.
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Abstract

Industry 4.0 and the associated idea of society 4.0 pose specific challenges for the concept of sustainable development. These challenges relate, inter alia, to responsibility, in which the changes to date have overall entailed: • a transition from ex post responsibility to ex ante responsibility (H. Jonas); • a transition from individual responsibility to corporate social responsibility. In the context of society 4.0 there is a need for shared responsibility. The problem of justice and therefore the implementation of sustainable development not only becomes an open problem, but also requires constant updating and specifi c optimisation.
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Abstract

The paper’s authors undertake the reflection on the stages of the evolution of Dietrich Bonhoeffer’s views on the Church and its role as it is played in the lives of its singular members and in the context of the Reformation’s ethical heritage. One can distinguish among three stages of the Bonhoefferian ecclesiology, deepening his vision of the Church. As far as the first one is considered, the Church is defined as the spiritual community of believers, outside of which salvation is impossible. At the second stage the German theologian accentuates the sinfulness of man as a member of the Church. Its recognition constitutes the basis for the transformation that can take place in the human individual due to accepting Christ into oneself. The third stage is stepping into the world of „before-final” matters in the full responsibility for the choices made by particular members of the ecclesial community. The Church, as Bonhoeffer saw it, was supposed to support itself on strong pillars: on freedom, personal responsibility, imitating Christ, neighbourly love, on sacraments and Gospel. In this aspect Bonhoeffer was the faithful continuator of the Reformation program.
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Abstract

A lot of interest has recently been put into the so-called ‘virtual cryptographic currencies’, commonly known as cryptocurrencies, along with its surrounding market. The blockchain technology that stands behind them is also becoming increasingly popular. From the perspective of maintaining energy security, an important issue is the process of mining individual cryptocurrencies, which is associated with very high energy consumption. This operation is usually related to the approval of new blocks in the blockchain network and attaching them to the chain. This process is carried out through performing complex mathematical operations by various devices, which in turn require high power and respectively consume a lot of energy. The impact of cryptocurrency miners on the power and energy demand level might gradually increase over time, therefore this issue shouldn’t be ignored. Comparing the above information in parallel with the growing need for providing demand side response (DSR) services in the Polish Power System, raises the question whether devices used for mining cryptocurrencies can be used for the purpose of balancing the power system. This paper presents an analysis of the possibility to provide the demand side response services by groups of cryptocurrency miners users. The analysis was carried out taking basic functional, technological and economical aspects of these devices’ operations into account.
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Abstract

The aim of the article is to examine the specific properties of language actions in terms of their moral evaluation. The author starts from the question whether responsibility for words has the same meaning as responsibility for a physical action. In her analysis, the author deliberates whether in both cases the same rules and criteria are applicable. Referring to the classical theory of speech acts proposed by John L. Austin, who introduced a fundamental division into constative and performative utterances and went on to distinguish illocutionary effects from perlocutionary consequences of speech acts, the author investigates how far a subject is responsible for the words he uses.
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Abstract

Modern regulations concerning railway bridges are based on the approach of structural dynamics, which is described in PN-EN standards. This paper presents the results of theoretical dynamic analysis of the HSLM-A train set loading on the structure of a pre-stressed concrete arch bridge - the first railway bridge of its type which was built in Poland (completed in 1959). The recommendations of PN-EN have been followed and modal analysis was carried out to define the sensitivity of the structure to chosen eigenforms. Additionally the paper presents a course of calculations and the conclusions obtained from the analysis of displacements, accelerations, and bending moments induced in the structure through a simulated passage of a high-speed train in the context of the requirements of PN-EN Standards. The conclusions from the current calculations can be used for dynamic analysis of bridges of similar structural solutions.
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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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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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Abstract

The application of immune serum is one of the most efficient method used formerly in the protection of raised piglets’/weaners’ health . The objective of the study was to determine specific antibody response during hyperimmunization of fatteners with a self-prepared subunit vaccine, and to propose production method of immune serum against Gram-negative bacteria antigens. The vaccine was administered every two weeks, 4 times. Individual and pooled serum samples were assayed for IgM, IgG and IgA antibodies against Histophilus somni recombinant Hsp60, H.somni rOMP40 and Pasteurella multocida LPS. Additionally total serum IgG and haptoglobin concentrations were measured. Two weeks after the first vaccination IgM antibody raised significantly against H.s. rOMP40 and LPS, whereas after 4 weeks it increased against rHsp60 antigens. Anti-LPS IgM antibody raised up stepwise till the end of the observation, but IgM antibody against H.s. rHsp60 and H.s. rOMP40 decreased in further samplings. A significant raise in IgG class H.s. rHsp60- -antibody was found 4 weeks after the first immunization and a similar raise against two remain- ing antigens after 6 weeks. The intensity of the reaction increased till the end of the experiment. The raise in IgA antibody level was observed only for H.s. rHsp60 antigen. Clinically observed, proper animal health and welfare were confirmed by haptoglobin concentration, which remained in physiological range. At least 4 booster doses were necessary to obtain hyperimmune serum containing a high level of antibodies against examined antigens. The number of immunizations influenced response profiles for specific IgM, IgG, IgA antibodies.
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Abstract

Specific requirements are designed and implemented in electronic and telecommunication systems for received signals, especially high-frequency ones, to examine and control the signal radiation. However, as a serious drawback, no special requirements are considered for the transmitted signals from a subsystem. Different industries have always been struggling with electromagnetic interferences affecting their electronic and telecommunication systems and imposing significant costs. It is thus necessary to specifically investigate this problem as every device is continuously exposed to interferences. Signal processing allows for the decomposition of a signal to its different components to simulate each component. Radiation control has its specific complexities in systems, requiring necessary measures from the very beginning of the design. This study attempted to determine the highest radiation from a subsystem by estimating the radiation fields. The study goal was to investigate the level of radiations received and transmitted from the adjacent systems, respectively, and present methods for control and eliminate the existing radiations. The proposed approach employs an algorithm which is based on multi-component signals, defect, and the radiation shield used in the subsystem. The algorithm flowchart focuses on the separation and of signal components and electromagnetic interference reduction. In this algorithm, the detection process is carried out at the bounds of each component, after which the separation process is performed in the vicinity of the different bounds. The proposed method works based on the Fourier transform of impulse functions for signal components decomposition that was employed to develop an algorithm for separation of the components of the signals input to the subsystem.
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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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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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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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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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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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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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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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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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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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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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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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