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Copyright of Przegląd Elektrotechniczny is the property of Przeglad Elektrotechniczny and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This study investigated the possibility of quantum effects arising from defects resulting from the use of textronic electroconductive thin films and evaluated their impact on control characteristics. A hybrid model, where the classical approach to determine stationary fields based on the boundary element method was combined with a quantum mechanical approach using nonequilibrium Green's functions, was created. The results of conductance and transmission coefficient simulations for different types of defects in the studied structure and a wide range of temperatures assuming two different control modes are presented. Based on the results, the conditions for the occurrence of quantum effects on the surface of conducting paths containing defects were specified, and their impact on conductance in the quantum mechanical approach was estimated. [ABSTRACT FROM AUTHOR]

The paper presents a method for solving electromagnetic field problems by applying impedance boundary conditions for systems including conducting bodies of nonlinear magnetic properties in an excited harmonic field. Three types of impedance boundary conditions were derived. A procedure for computing surface impedance based on the transfer matrix is proposed. This procedure has been tested by comparing computational results to calculations where time function distortions were considered, and to the experimental data.

This paper analyzes the influence of the skin effect and the proximity effect on the inductance and impedance of thin conductive layers. The motivation for taking up this topic is the initial assessment of the possibility of using conductive layers deposited with the PVD technique on textile materials as strip or planar transmission lines of high-frequency signals (e.g., for transmitting images). This work pursues two goals. The first of them is to develop and test a numerical procedure for calculating the electromagnetic field distribution in this type of issue, based on the fundamental solution method (FSM). The second aim is to examine the impact of the skin phenomenon on the resistance, inductance and impedance of thin conductive paths. The correctness and effectiveness of FSM for the analysis of harmonics of electromagnetic fields in systems containing thin conductive layers were confirmed. Based on the performed simulations, it was found that in the frequency range above 10 MHz, the dependence of resistance and impedance on frequency is a power function with an exponent independent of the path width. Moreover, it was found that for paths with a width at least several times greater than their thickness, the dependence of the phase shift between current and voltage on frequency practically does not depend on the path width. [ABSTRACT FROM AUTHOR]

The article presents cost of equity estimation of capital groups from the fuel and energy sector, listed at the Warsaw Stock Exchange, based on the Capital Asset Pricing Model (CAPM). The objective of the article was to perform a valuation of equity with the application of CAPM, based on actual financial data and stock exchange data and to carry out a sensitivity analysis of such cost, depending on the financing structure of the entity. The objective of the article formulated in this manner has determined its’ structure. It focuses on presentation of substantive analyses related to the core of equity and methods of estimating its’ costs, with special attention given to the CAPM. In the practical section, estimation of cost was performed according to the CAPM methodology, based on the example of leading fuel and energy companies, such as Tauron GE and PGE. Simultaneously, sensitivity analysis of such cost was performed depending on the structure of financing the company’s operation.

Copyright of Przegląd Elektrotechniczny is the property of Przeglad Elektrotechniczny and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Numerical research into the QCL tunability aspects in respect to being applied in chemical substance detection systems is covered in this paper. The QCL tuning opportunities by varying power supply conditions and geometric dimensions of the active area have been considered. Two models for superlattice finite (FSML) and infinite (RSM) size were assumed for simulations. The results obtained have been correlated with the absorption map for selected chemical substances in order to identify the potential detection possibilities. [ABSTRACT FROM AUTHOR]

Copyright of Przegląd Elektrotechniczny is the property of Przeglad Elektrotechniczny and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Inzynieria Mineralna is the property of Polskie Towarzystwo Przerobki Kopalin and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Inzynieria Mineralna is the property of Polskie Towarzystwo Przerobki Kopalin and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Przegląd Elektrotechniczny is the property of Przeglad Elektrotechniczny and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Safety & Fire Technology / Bezpieczeństwo i Technika Pożarnicza is the property of Centrum Naukowo-Badawcze Ochrony Przeciwpozarowej and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Background: The aim of the study was to evaluate the effect of Allopurinol on intestinal ischemia-reperfusion injury and xanthine oxidase system. Material and methods: 70 Buffalo rats were divided into 5 groups of 14. Group I was the control group. The animals of groups II and IV were subjected to 50 minutes of acute intestinal ischemia. The animals of groups III and V were subjected to 50 minutes of acute intestinal ischemia followed by 60 minutes of reperfusion. The rats of group IV and V were pretreated with Allopurinol for three days before surgery. Total intestinal ischemia was produced by clamping the mesenteric vessels. Mucosal changes underwent histopathological evaluation according to the scoring system (0-5) described by Chiu. Biochemical tests of xanthine oxidase activity were performed in supernatants of small intestine homogenates. Results: The administration of Allopurinol significantly reduced mesenteric ischemia-reperfusion injury as weft as intestinal xanthine exidase activity. However, there was no significant difference in the xanthine oxidase activity between non-pretreated rats subjected to ischemic processes and the control group. It was also noted that beneficial action of Allopurinol began during the ischemic phase, before reperfusion. Conclusions: It can be concluded that the protective effect of Allopurinol against intestinal ischemia-reperfusion is not only related to the reperfusion component, The role of xanthine oxidase in the processes of injury resulting from blood flow disturbances remains a matter of controversy. [ABSTRACT FROM AUTHOR]

Copyright of Polish Surgery / Chirurgia Polska is the property of VM Medica-VM Group (Via Medica) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Acta Angiologica is the property of VM Medica-VM Group (Via Medica) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)