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Number of results: 174
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Abstract

The paper is devoted to explication of one of the advantages of heat and electricity cogeneration, rarely considered in technical literature. Usually attention is paid to the fact that heat losses of the heat distribution network are less severe in the case of cogeneration of heat in comparison with its separate production. But this conclusion is also true in other cases when the internal consumption of heat is significant. In this paper it has been proved in the case of two examples concerning trigeneration technology with an absorption chiller cooperating with a combined heat and power (CHP) plant and CHP plant integrated with amine post-combustion CO2processing unit. In both considered cases it might be said that thanks to cogeneration we have to do with less severe consequences of significant demand of heat for internal purposes.

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Authors and Affiliations

Andrzej Ziębik
Paweł Gładysz
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Abstract

The aim of this article is to analyze the relationship between ideology and fantastic literature using the example of Jean-Pierre Andrevon's fantastic novel L’Oeil derrière l’épaule. While fantastic literature as a genre is most often the carrier of right-wing, reactionary and conservative values (Lovecraft, Ray), Andrevon remains the specific case of a writer who openly defines himself as a leftist. The analysis of the “ideology-effect” (the unconscious ideological mask of the text according to Hamon) and of the “value-effect” (ideas that the text consciously promotes according to Jouve), as well as Hamon's points of textual ideological value and carriers of ideological distortions, permits a conclusion that the author did not adopt any ideological stance a priori and that the global value (right-wing and left-wing) emanating from the text is freedom.
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Authors and Affiliations

Katarzyna Gadomska
1

  1. Uniwersytet Śląski, Katowice
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Abstract

The problem of transmitting vibrations with audible frequencies by steel springs, constituting the vibration isolation system was considered in this paper. The analytical relationships allowing determining the value of the transmissibility for the springs resonance frequencies responsible for the transmissibility of high frequency vibrations have been derived and checked by means of FEM method. Also the occurrence of the increasing stresses in the springs in the areas between the resonances has been shown. The typical system, i.e. the serial system with rubber cushion, has been analyzed, reducing the transmission of high frequency vibrations by the spring. It has been shown that the transmission is reduced not as a result of differences in the wave impedance of the boundary of both media but due to the increased dispersion of energy in the rubber, and the analytical relationships allowing the evaluation of the effectiveness of this method have been derived.
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Authors and Affiliations

Jerzy Michalczyk
Leszek Majkut
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Abstract

The paper presents an analysis of energy and economic effectiveness of the combined heat and power (cogeneration) technologies fired with natural gas that may be deemed prospective for the Polish electric power system. The current state of the cogeneration technologies fired with natural gas in Poland is presented. Five cogeneration technologies fired with natural gas, prospective from the point of view of the Polish electric power system, were selected for the analysis. Namely, the paper discusses: gas-steam combined heat and power (CHP) unit with 3-pressure heat recovery generator (HRSG) and steam interstage reheat, gas-steam CHP unit with 2-pressure HRSG, gas-steam CHP unit with 1-pressure HRSG, gas CHP unit with small scale gas turbine, operating in a simple cycle and gas CHP unit with gas engine. The following quantities characterizing the energy effectiveness of the cogeneration technologies were selected for the analysis: electricity generation efficiency, heat generation efficiency, primary energy savings (PES) and CO2 unit emission. The economic effectiveness of particular technologies was determined based on unit electricity generation costs, discounted for 2019, including the costs of purchasing CO2 emission allowances. The results of calculations and analyses are presented in a table and on a figures.

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Authors and Affiliations

Bolesław Zaporowski
ORCID: ORCID
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Abstract

This commentary on the Court of Justice’s ruling in the Pawlak case concentrates on questions of the judicial application of EU law, in particular EU Directives. On the basis of the recent jurisprudence of the Court the authors present three issues: 1) the incidental effects of EU law for the procedural provisions of Member States; 2) the inability to rely on an EU directive by a member state’s authority in order to exclude the application of national provisions which are contrary to a directive; 3) the limits of the duty to interpret national law in conformity with EU law from the perspective of the Court of Justice and the referring court. Further, the article presents the judicial practice of the Polish Supreme Court, and in particular the follow-up decision of this Court not only taking into the account the ruling of the ECJ but also showing how the limitation of a conforming interpretation can be overcome in order to give full effect to EU law. In the authors’ view, this case is worth noting as an example of judicial dialogue in the EU.

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Authors and Affiliations

Dawid Miąsik
Monika Szwarc
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Abstract

In cities with large educational institutions, the inflow of educational migrants is important for con-sumption demand, and can trigger multiplier effects. The main aim of this article is to show the mecha-nism of the aggregate demand-income effect created by educational migration in the Polish city of Opole. An estimate of this effect is provided, based on questionnaire research among a sample of 1 075 students from all institutions of higher education located in the city. The estimated effects analysed concern the direct consumption impulse, as well as the indirect job creation and increase in income for providers of accommodation for students, in turn triggering increased consumption demand. While the results must be interpreted with care, an estimated 15 per cent of consumption demand created through expenditure of migrant students (about PLN 175 400 000) and 485 extra job show the significance of such expenditure for the local economy.

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Authors and Affiliations

Diana Rokita-Poskart
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Abstract

Noise reduction inside waveguide systems has gained momentum owing to a great interest in it. To attenuate the sound in a broad frequency range, this study aims to compare the effects of two acoustic liners, a perforated plate backed by an air cavity (PP-Air cavity), or by a porous material (PP-PM), on the acoustic behaviour of lined ducts using a numerical model to compute the multimodal scattering matrix. From this matrix, the reflection and the transmission coefficients are computed and therefore the acoustic power attenuation is deduced. Moreover, the effects of geometry of ducts with and without changes in the section are investigated. The numerical results are obtained for five configurations, including cases of narrowing and widening of a duct portion with sudden or progressive discontinuities. Accordingly, numerical coefficients of reflection and transmission as well as the acoustic power attenuation show the relative influence of acoustic liners in each type of configuration.

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Authors and Affiliations

Amine Makni
Mohamed Taktak
Mabrouk Chaabane
Mohamed Haddar
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Abstract

The hierarchical structure of InSe<β-CD<FeSO4>> composition with 4-fold grade expansion was synthesized with the intercalation-deintercalation technique. Electrical properties of the structure obtained were examined using impedance and thermostimulated current spectroscopy methods. Influence of temperature, static magnetic field and illumination on electrical properties of the synthesized compound was investigated. Changes in the impurity spectrum of the expanded hierarchical structure were analyzed and extraordinary magneto- and photoimpedance behavior of InSe<β-CD<FeSO4>> at room temperature was explained.

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Authors and Affiliations

T. Popławski
I. Bordun
A. Pidluzhna
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Abstract

The paper presents an analysis of the influence of the energy generated from renewable sources on an improvement in the energy efficiency of public utility building and households. It also presents the current state of the technologies for the production of electricity from renewable sources, as well as their share in the national power supply system. The conducted analysis concerns both micro, as well as large systems generating electricity. Systems generating power from renewable sources are gaining in popularity. With an increasing awareness in the society of the beneficial influence that renewable power generating systems have on the environment, as well as the support in form of various programs offering subsidies for the construction of new systems, power generation from renewable sources is becoming increasingly popular and common. Although the renewable energy systems are still not widely considered to be a profitable solution, systems using renewable sources of energy are positively perceived and treated as a new trend in the construction of multi or single-family residential buildings. The increasing share of the renewable energy in the national power supply system significantly reduces the demand for energy produced from conventional sources. This obviously translates into a reduced consumption of primary energy, for example, fossil fuels, and, in turn, leads to the reduced exploitation of natural resources, thus contributing to the protection of the natural environment. A reduced consumption of fossil fuels also means a significant reduction in environmental pollution during their processing into electricity or heat. Actions aiming at improving energy efficiency and reducing final energy consumption are being undertaken by many countries all over the world, and by the European Union. In 2012, the European Parliament and the Council issued Directive 2012/27/EU obliging the Member States to initiate actions aiming at a reduction in the consumption of final energy by 1.5% a year. The paper presents the current status of generation of energy from renewable sources during the last 13 years. The ways for using energy from the renewable sources to improve the energy efficiency of facilities were also discussed.

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Authors and Affiliations

Sławomir Sowa
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Abstract

Research suggests that placebo can reduce the misinformation effect. We aimed to examine for the first time whether placebo administered in the guise of caffeine can reduce the misinformation effect. One hundred and twenty -three healthy volunteers were randomly assigned to four groups in a 2 Placebo (Present, Not Present) × 2 Narrative (Misleading, Correct) study design. Participants from placebo groups drank 100 ml of placebo solution. They were told that it was water mixed with caffeine which could positively influence their memory. After three minutes, they watched a short movie clip as an original event and read a narrative with misleading details or correct details as a postevent information; they then completed a 22 -item, two -alternative forced -choice questionnaire. The results reveal that the misinformation effect occurred. Although participants in the placebo with misinformation group scored better than participants who did not drink placebo and read the narrative containing misleading details, the difference was not statistically significant. Thus, it is concluded that placebo might not be enough to reduce the misinformation effect when it is administered in the guise of caffeine.

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Authors and Affiliations

Jakub Nastaj
Malwina Szpitalak
ORCID: ORCID
Przemysław Bąbel
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Abstract

Several human studies have reported that capsaicin has anti-pruritic effects. Moreover, sever- al concentrations of topical capsaicin have been used to alleviate itch. The aim of this study was to investigate the anti-pruritic effect of capsaicin against histamine-induced pruritus compared with that of topical steroid or vehicle in 15 healthy beagles. Fifteen dogs were divided into three groups (n = 5 each), and treated topically with one of the following on the left side of the neck: capsaicin, positive control (steroid), or negative control (vehicle). Each treatment was performed twice daily for 8 days. All dogs were injected with histamine intradermally before treatment and on the 2nd, 4th, 6th, and 8th days of the treatment to evoke itch. Pruritus, wheal, and erythema intensity were assessed at each evaluation; cutaneous temperature was also recorded. On the final day, skin biopsy was conducted for histopathological evaluation for all dogs. The severity of pruritus was lesser in the capsaicin-treated group compared with the negative control group on day 8 (p<0.05). In the capsaicin and steroid groups, wheal size, erythema index, and cutaneous temperature also decreased compared with pretreatment. Histopathological evaluation showed that the capsaicin-treated group had a higher number of inflammatory cells in the dermis com- pared to the vehicle control group; however, the steroid-treated group showed less severe inflam- matory reactions than the vehicle control group. These results suggest that capsaicin cannot reduce inflammation but may play a helpful role in reducing pruritus in dogs.

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Authors and Affiliations

S. Bae
J. Yu
H. Jeong
T. Oh
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Abstract

Empathy and psychopathy seem to be two distant extremes, which only differ, with nothing similar. Therefore, the question that seems to be surprising is whether such a theoretical perspective is justified. Empathy exerts significant influence on social relationships and is associated with moral development, whereas psychopathy seems to be an opposite phenomenon, as it is associated with the lack of deep interpersonal bonds and the violation of legal norms. As studies from various disciplines and scientific areas indicate, such concepts as behavioral effectiveness, morality or altruism might help explain the complex nature of the interrelationship between psychopathy and empathy. The authors tried to explore and describe the complexity of the two presented concepts in the light of the conducted research, and the resulting theoretical and empirical implications.

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Authors and Affiliations

Beata Pastwa-Wojciechowska
Maria Kaźmierczak
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Abstract

The subject of the research presented in this paper were financial results of mining industry enterprises (PKD 5 – P olish C lassification of A ctivity – “Mining of coal and lignite”) in 2007–2019. The research was conducted using relative and absolute financial measures, forming an extensive and coherent set of features characterizing their financial condition. The purpose was to measure and evaluate the efficiency of examined enterprises operation, considered as an attribute of development as well as factors describing and determining it. This evaluation was made against the background of ongoing restructuring processes taking into account their potential effects.

The article presents the course of the process of adapting P olish hard coal mining to market economy conditions after 1989. The process can be conventionally divided into several periods. The scope and intensity of changes in the mining industry followed the subsequent government programs for mining industry restructuring.

The lignite mining has not implemented any specific restructuring programs. The remedy processes were mainly related to organizational and ownership changes.

In relation to operation efficiency and value creation three turning points in the development path of enterprises were highlighted – 2011, 2015 and 2017, while the period of strong deterioration of results occurred in 2011–2015. I t was proved that restructuring processes did not affect the operating return on sales. However, there was a strong relation between changes in economic conditions on the coal market (prices) and the accumulation rate.

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Authors and Affiliations

Eugeniusz Jacek Sobczyk
Jarosław Kaczmarek
Kamil Fijorek
Michał Kopacz
ORCID: ORCID
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Abstract

The article discusses the evolution of Marian Smoluchowski’s reasoning in his research on causality and understanding the essence of chance. Initially, Smoluchowski focused on the epistemic study of causality, looking for evidence supporting the kinetic-molecular theory. In proving the causes of Brownian motion, he used the concepts of physical causality. The fundamental change in Polish physicist's perception of causality was the understanding of the position of chance on the cause-effect line. Introducing mathematical relations into his considerations, he analyzed the aspect of the occurrence of the effect. The chance suitable for calculating probability was distinguished from the chance in a broader sense by the essential regularity of the frequent recurrence of the phenomenon, regardless of the knowledge of the cause. Smoluchowski's merit was the distinction between the philosophical and physical understanding of causality, chance and probability theory. Shifting the considerations on the nature of chance to the ontological plane moved the study of chance into the area of science, thus leading to the practical application of probability theory in physics.
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Authors and Affiliations

Jan Grzanka
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Abstract

This paper discusses the estimation of flow velocity from a multi-sensor scenario. Different estimation methods were used, which allow the effective measurement of the actual Doppler shift in a noisy environment, such as water with air bubbles, and on this basis the estimation of the flow velocity in the pipe was calculated. Information fusion is proposed for the estimates collected. The proposed approach focuses on the density of the fluid. The proposed method is capable of determining the flow velocity with high accuracy and small variations. Simulation results for plastic and steel (both galvanized and non-galvanized) pipes show the possibility of accurate fluid flow measurements without the need for sensors inside the pipe.
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Authors and Affiliations

Pawel Biernacki
1
Stanislaw Gmyrek
1
Wladyslaw Magiera
1

  1. Faculty of Electronics, Photonics and Microsystems, Department of Acoustics, Multimedia and Signal Processing, Wroclaw University of Science and Technology, Wrocław, Poland
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Abstract

What is migration? Who are the people that migrate, and what drives them to do so?
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Authors and Affiliations

Józef M. Fiszer
1 2

  1. Institute of Political Studies, Polish Academy of Sciences
  2. Lazarski University
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Abstract

Research concerning temporal variations of suspended sediment concentration during period of high water stages was done in the lower course of the Obra River near Międzyrzecz (Western Poland). The analysis regarding dependence of mean suspended sediment concentration and discharge allowed to determine the way of suspended sediment supply to the river bed during high water stages. It was supposed that exposures of glacial and fluvioglacial sediments in high concave banks could be an important factor influencing the amount of delivery of suspended material. Besides, normal hysteretic loops (oriented clockwise) were observed in cross-sections 4 and 5. That fact would suggest that transported material originates form the Obra River bed or its vicinity. The process of sediment accretion was observed on a fragment of drowned floodplain during high water stages. Collection of samples of freshly deposited sediment and grain size analysis allowed to illustrate the mechanism of forming floodplain sediments. It also was possible to draw near conditions of forming such sediments in the past.
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Authors and Affiliations

Zygmunt Młynarczyk
Marcin Słowik
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Abstract

The article examines the environmental performance of a diesel generator that runs on a biofuel mixture. Biofuels are considered to be more environmentally friendly than traditional petroleum products and have become popular alternatives in the field of electricity production. To reduce dependence on petroleum fuels and decrease harmful exhaust-gas emissions from diesel generators, it is suggested to use biodiesel fuel and its mixture with diesel fuel. Various environmental indicators were measured and analyzed in this study, including the emissions of harmful substances, carbon dioxide, nitrogen oxides and particulates. By using biofuels, pollutant emissions are expected to be reduced because biofuels are made from renewable sources such as vegetable oils or biomass. The results of the study show that the use of a biofuel mixture in a diesel generator leads to a significant reduction in the emission of harmful substances compared to the use of traditional petroleum products. A reduction in the emissions of carbon dioxide and nitrogen oxides was found, which contributes to a reduction of the impact on climate change and air pollution. In addition, a decrease in particle emissions was noted, which contributes to the improvement of air quality and people’s health. The goal was achieved by researching the impact of a mixture of diesel and biodiesel fuel on the technical, economic and environmental indicators of an autonomous diesel generator. The regulation of the composition of the fuel mixture ensured the preservation of the power of the generator in all its modes of operation, while reducing the cost of purchasing fuel by 10% and reducing the smokiness of exhaust gas by up to 57%, depending on the mode of operation of the diesel engine.
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Authors and Affiliations

Alexander Galushchak
1
ORCID: ORCID
Serhii Burlaka
2
ORCID: ORCID
Ihor Kupchuk
2
ORCID: ORCID
Valerii Bondarenko
3
ORCID: ORCID
Yaroslav Gontaruk
4
ORCID: ORCID

  1. Vinnytsia National Technical University, Ukraine
  2. Engineering and Technology Faculty, Vinnytsia National Agrarian University, Ukraine
  3. National University of Life and Environmental Sciences of Ukraine, Ukraine
  4. Vinnytsia National Agrarian University, Ukraine
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Abstract

The climate as we know it is a natural resource that is becoming depleted due to the rising demand for energy. The most emission-intensive sectors are those providing for our comfort and welfare. We discuss these issues with Prof. Mirosław Miętus from the Institute of Meteorology and Water Management.
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Authors and Affiliations

Mirosław Miętus
1

  1. Instituteof Meteorology and Water Management– National Research Institute (IMiGW-PIB), Warsaw, Poland
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Abstract

The paper presents the results of simulations and experiments in the field of control of the low damping and time delay oscillating system. This system includes a quadcopter hovering at a very low altitude, and the altitude is controlled. The time delay is introduced mainly by the remote control device. In order to handle the quadcopter at low altitudes, a proportional-integral controller with a negative proportional coefficient is used. Such an approach can provide good results in the case of an oscillating, low damped system. This method of steering, which uses a typical radio control transmitter, can be used on any commercially available leisure drone. Feedback is provided by a camera and algorithms of computer vision. The presented results were obtained experimentally using free flight – without a harness. Different types of controllers are used to control horizontal shift and altitude.
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Bibliography

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Authors and Affiliations

Konrad Urbański
1
ORCID: ORCID

  1. Institute of Robotics and Machine Intelligence, Poznan University of Technology, Piotrowo 3A str., 60-965 Poznan, Poland
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Abstract

The progressive development of miniature systems increases the demand for miniature parts. Reducing the size of manufactured components on one hand is a serious challenge for traditional technologies, but on the other hand, mainly by removing the energy barrier opens the possibility of using other unconventional techniques. A good example is the ultrasonic excitation of the punch during the micro-upsetting process. The anti-barreling phenomenon and dependent on the amplitude of vibrations, intensive deformation of the surface layers in contact with the tools at both ends of the sample was noted. Based on the measured strains and stresses, an increase in temperature in the extreme layers to approx. 200°C was suggested. By adopting a simplified dynamic model of the test stand, the possibility of detaching the surface of the punch from the surface of the sample was demonstrated.

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Authors and Affiliations

W. Presz
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Abstract

Viral diseases have caused devastating effect on poultry industry leading to significant losses in economy of world. In the presented study, the ability of Newcastle disease virus (NDV), infectious bursal disease virus (IBDV) and avian influenza virus (AIV) to grow in two cell lines was evaluated. Both chicken embryo fibroblast (CEF) and DF-1 cells were used and cytopathic effects (CPE) produced by these viruses were observed. The titer of virus in terms of TCID50 was determined after 24h up to four days for each virus. The same type of CPE was observed for all viruses used in the study in both DF-1 and CEF cells. IBDV showed CPE causing rounding of cells while NDV caused formation of multicellular large nuclei, cell fusion and rounding of cells. Giant cells with inclusions and aggregation of cells with intact monolayer was observed for AIV. In growth kinetic study, higher titer of IBDV and NDV was observed in CEF cells than DF-1 cells while for AIV, DF-1 cells showed higher titer than CEF cells. These results would be useful for furthers comparative studies on growth of different cell lines of various viruses to find a suitability for vaccine production.
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Authors and Affiliations

S. Anam
1
S.U. Rahman
1
Shazma Ali
M. Saeed
2
S.M. Goyal
3

  1. Institute of Microbiology, Faculty of Veterinary Science, University of Agriculture Faisalabad, Pakistan
  2. National Institute of Food Science and Technology, University of Agriculture Faisalabad, Pakistan
  3. College of Veterinary Population Medicine, 1333 Gortner Avenue, University of Minnesota, USA
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Abstract

This study aims to explore the effects of age across adult groups on selected aspects of language learning. To achieve the aim, a study was conducted at the Open University of University of Warsaw. It focuses on reasons for taking up learning, relative importance of individual skills, major difficulties, individual goals, emotions and self-assessed ability to learn. The assumption that adults represent a single age group is questioned and the results are interpreted in terms of practical implications for course design.

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Authors and Affiliations

Agata Klimczak-Pawlak
Sylwia Kossakowska-Pisarek
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Abstract

The paper presents an evaluation with the Type A and B methods for standard uncertainties of coefficients of a polynomial function of order k determined by n points obtained by measurement of input and output quantities. A method for deriving a posteriori distributions of function coefficients based on the transformation of estimator distributions without assuming any a priori distributions is presented. It was emphasized that since the correct values of the standard uncertainty of type A depend on the √ n-k-3 and not on the p √ n-k-1, therefore, with a small number of measurement points, the use of the classical approach leads to a significant underestimation of uncertainty. The relationships for direct evaluation with the type B method of uncertainties caused by uncorrected systematic additive (offset error) and multiplicative (gain error) effects in the measurements of both input and output quantities are derived. These standard uncertainties are determined on the basis of the manufacturers’ declared values of the maximum permissible errors of the measuring instruments used. A Monte Carlo experiment was carried out to verify the uncertainties of the coefficients and quadratic function, the results of which fully confirmed the results obtained analytically.
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Authors and Affiliations

Mykhaylo Dorozhovets
1 2

  1. Rzeszow University of Technology, Faculty of Electrical and Computer Engineering, Department of Metrology andDiagnostic Systems, Wincentego Pola, 2A, 35-959 Rzeszow, Poland
  2. Lviv Polytechnic National University, Institute of Computer Technologies, Automation and Metrology, Department ofInformation Measuring Technology, Bandera str., 12, 79013 Lviv, Ukraine

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