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Number of results: 10
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Abstract

When studying porous materials, most acoustical and geometrical parameters can be affected by the presence of uncertainties, which can reduce the robustness of models and techniques using these parameters. Hence, there is a need to evaluate the effect of these uncertainties in the case of modeling acoustic problems. Among these evaluation methods, the Monte Carlo simulation is considered a benchmark for studying the propagation of uncertainties in theoretical models. In the present study, this method is applied to a theoretical model predicting the acoustic behavior of a porous material located in a duct element to evaluate the impact of each input error on the computation of the acoustic proprieties such as the reflection and transmission coefficients as well as the acoustic power attenuation and the transmission loss of the studied element. Two analyses are conducted; the first one leads to the evaluation of the impacts of error propagation of each acoustic parameter (resistivity, porosity, tortuosity, and viscous and thermal length) through the model using a Monte Carlo simulation. The second analysis presents the effect of propagating the uncertainties of all parameters together. After the simulation of the uncertainties, the 95% confidence intervals and the maximum and minimum errors of each parameter are computed. The obtained results showed that the resistivity and length of the porous material have a great influence on the acoustic outputs of the studied model (transmission and reflection coefficients, transmission loss, and acoustic power attenuation). At the same time, the other physical parameters have a small impact. In addition, the acoustic power attenuation is the acoustic quantity least impacted by the input uncertainties.
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Authors and Affiliations

Hanen Hannachi
1 2
Hassen Trabelsi
1
Marwa Kani
1 2
Mohamed Taktak
3 4
Mabrouk Chaabane
2
Mohamed Haddar
2

  1. Laboratory of Mechanics, Modeling and Productivity (LA2MP), National School of Engineers of Sfax, University of Sfax, Sfax, Tunisia
  2. Faculty of Science of Sfax, University of Sfax, Sfax, Tunisia
  3. Laboratory of Mechanics, Modeling and Productivity (LA2MP), National School of Engineers of Sfax, University of Sfax, Tunisia
  4. Faculty of Sciences of Sfax, University of Sfax, Tunisia
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Abstract

This work determined the solid-water distribution coefficient Kd, the Freundlich constant KF and the organic carbon normalized coefficient K0c of ibuprofen in natural, aquifer sediments. They are characterized as silt sediments with different clay and sand fraction contents varied in specific surface areas. Content of organic carbon and pH are on the same level. For determining sorption coefficients values of ibuprofen in sediments, its concentration was measured in the aqueous and calculated in the solid phase. Batch tests were conducted following OECD Guideline 106. The resulting Kd values ranged between 1.14 and 2.29 L/kg, ~ between 0.25 and 5.48 and Koc between 1.22 and 2.53 for ibuprofen in sediments SI and S2, respectively. These experiments proved that the presence of clay minerals beside organic carbon and pH might be relevant in sorption of ibuprofen in sediments. A comparison of experimentally determined Koc with modelled Koc calculated on the base of octanol-water partitioning coefficient K0w shows that the prediction of sorption behaviour cannot be based only on Kow· This is probably due to the fact that these approaches well describe hydrophobic interactions, but fail to predict sorption of polar and ionic compounds.
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Authors and Affiliations

Katarzyna Styszko
Katarzyna Sosonowska
Piotr Wojtanowicz
Janusz Gołaś
Jerzy Górecki
Mariusz Macherzyński
ORCID: ORCID
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Abstract

Hg concentration was studied in waters of 16 lakes in the Suwałki Landscape Park. The samples of lake water were collected from the surface zone and I m above the bottom, in the deepest site of the lakes. Apart from Hg concentration, the measurements included: the pH, soluble oxygen, water saturation with oxygen, electrolytic conductivity and total hardness of water. Hg concentration varied from lake to lake, but remained at the same levels in consecutive years. It has been found that Hg concentration in the bottom zone is higher than that in the surface zone. Significant differences were found between mean Hg concentrations in the bottom zone both during the summer and winter stagnation. No significant differences were found in mean Hg concentration in surface waters in different seasons of the year.
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Authors and Affiliations

Wojciech Dobicki
Ryszard Polechoński
Przemysław Pokorny
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Abstract

In this topic review the results of the X-band electron paramagnetic resonance (EPR) measurements of Mn, Co, Cr, Fe ions in YAlO3 (YAP) crystals and Fe ions in LiNbO3 (LNO) crystals and of chromium doped Bi12GeO20 (BGO) and Ca4GdO(BO3)3 single crystals, are presented. It is well known that the oxide crystals (for example:YAP, LNO, BGO) are one of the most widely used host materials for different optoelectronic applications. The nature of point defect of impurities and produced in the oxide crystal after irradiation by bismuth ions and after irradiation by the 235U ions with energy 9.47 MeV/u and fluency 5 × 1011 cm−1 is discussed. The latter is important for applications of these oxide crystal as laser materials.

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Authors and Affiliations

I. Stefaniuk
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Abstract

The EFQM recognition system is an acknowledged method of assessing business excellence understood as the degree of implementation of quality management in an organization. The paper aims to examine whether a high rating under the EFQM recognition system simultaneously means a high general management maturity level. The investigation covers the 35 organizations that won EFQM awards in Portugal. The study is based on points awarded to organizations under the EFQM recognition system and on questionnaires/interviews with managers responsible for quality management in the studied organizations. The results indicate a positive and robust correlation between the quality management implementation (rating under the EFQM recognition system) and general management maturity. The study helps to close the gap in the literature regarding the relationship between quality management and management maturity in an organization.
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Authors and Affiliations

Luís Pimentel
1
ORCID: ORCID
Piotr Rogala
2
ORCID: ORCID

  1. BRU-UNIDE, ISCTE-IUL, University Institute of Lisbon; Universidade Europeia (Lisbon), Portugal
  2. Wroclaw University of Economics and Business, Department of Quality and Environmental Management, Poland
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Abstract

Strategic Informatics is a monograph of the field of computer science in the field of; Its strategic development waves, the challenges of technological progress in the context of the strategic role of computer science, the main strategy-oriented applications in business, healthcare, agriculture, education and private home, strategic challenges of computer science in the humanities, digital state and city, sustainable development and information ethics, morality, and rights.
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Authors and Affiliations

Kazimierz Kowalski
1

  1. Professor Emeritus, California State University, Dominguez Hills
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Abstract

Szargut proposed the algorithm for determination of the influence of irreversibility of components of thermal process on the emission of CO2 [6]. In the presented paper, basing on Szargut's proposal, the example of analysis of influence of operational parameters of coal fired power plant on the local increase of CO2 emission is presented. The influence of operational parameters on the local exergy losses appearing in components of investigated power plant are simulating making use of the semi-empirical model of power plant.

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Authors and Affiliations

Wojciech Stanek
Michał Budnik
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Abstract

The Historical-Philosophical Faculty of the Academy of Arts and Sciences, including its Committee on History, was involved in very intensive scholarly and editorial activity. Among the many institutions which broadly cooperated with the Academy, one can indicate the Kórnik Library. The scholars representing the Lviv and Cracow academic circles composed the dominant group of those who conducted their research in the Kórnik Library. The impressive source editions, initiated by the Academy, were significantly based on the Kórnik collections. The scholars were interested in those sources dealing mainly with history of the Polish state and nation, the history of its law, literature, religion and warfare. The cooperation between these two institutions also included making excerpts, copying and answering to the requests of the scholars, as well as exchanges of various publications. As an addition, the Kórnik Library offered a whole collection of its own publications to the Cracow researchers. The mutual contacts were often based on personal friendship and can be considered as an example of friendly academic cooperation being utilised to fulfil a common task. No doubt this cooperation contributed to the development of Polish academia, enriching the status of research on the history of Poland, enabling numerous source editions and monographs as well as helping to maintain the direct contacts between Polish scholars living and working in various parts of the Polish lands under Austrian and German occupation at the turn of the twentieth century.

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Authors and Affiliations

Gabriela Sznajder
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Abstract

In this paper, the author derives theoretical formulae for calculating of squeezing forces. This report is the first one concerning the method of forming stepped shafts by longitudinal cold rolling. The formulae of the radial squeezing forces for the final passage of longitudinal rolling were calculated under the Huber hypothesis of plastic deformation and maximum shear stress.

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Authors and Affiliations

Marek Kowalik

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