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Statistical Analysis of Financial and Economic Condition in Companies Listed on the Warsaw Stock Exchange

100%
Łuniewska M.
Folia Oeconomica Stetinensia
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2008
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vol. 7
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issue 1
98-108
EN
The analysis of securities is an essential element of investment. It is a complex and, very frequently, long-lasting process. Depending on the assumed time perspective of an investment, the analysis may be carried out on the basis of appropriate tools within technical or fundamental analysis. Assuming that the investment is long-term, the methods of fundamental analysis, particularly the indicator analysis are be useful. Additionally, in securities analyses taxonomic methods are more frequently used, which allows for the evaluation of the securities quality through the synthetic analysis of statistical economic and financial indicators. Methods of linear arrangement used to assess the companies' fundamental strength are based on the economic and financial indicators. These indicators define in a numerical manner the relations between economic and financial values, which allows for conclusions on the condition of the examined economic entities, sectors or markets. Furthermore, indicators are a source of data in quantitative analyses, they are diagnostic variables in research studies. Thus this situation poses a few crucial questions:- how do the economic and financial indicators rule on the stock market?- what is their level, do they maintain the norms?- what is the quality of data on the basis of which securities analyses are carried out?The main goal of the article is to analyze the fundamental power of companies listed on Warsaw Stock Exchange (WSE) by using TMAI value (in space and time). The study was performed in the period of 2005-2008 (the first quarter of 2008). Thus, the base was constituted by 126 companies. Banks and other financial institutions were excluded. Within the macrosectors existing on the Polish capital market, a statistical analysis of the level of economic and financial indicators characterizing particular companies was performed.
2
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MODELLING OF CONTACT PROBLEMS INVOLVED IN ENSURING THE SAFETY OF RAIL TRANSPORT

84%
Strzyżakowski Z., Rydygier E.
LogForum
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2013
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vol. 9
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issue 4
231-238
EN
Background: Mathematical modelling aids diagnostics the track and rolling stock, as it often for technical reasons it is not possible to obtain a complete set of measurement data required to diagnose the rail and wheel deformation caused by the impact of a rail vehicle on the track. The important issue in a railway diagnostics is to study the effects of contact wheel and rail. Diagnostics investigations of track and rolling stock have a fundamental role in ensuring the safety of transport of passengers and goods. The aim of the study presented in the paper was to develop simulation methods of mathematical modelling of the wheel-rail system useful in the diagnostics of the track and a railway vehicle. Methods: In the paper two ways of modelling were presented and discussed. One of these ways is the method which consists in reducing the contact issue to field issue and solving the identification of the field source in 2-D system. Also presented a different method designed on the basis of the methods using one period energy concept. This method is adapted for modelling the dynamics of the contact wheel-rail for the normal force. It has been shown that the developed modelling methods to effectively support the study on the effects of mechanical and thermal of contact wheel-rail and contribute to the safety of operations. Results and conclusions: In the case of field sources identifications two specific issues were examined: the issue of rail torsion and the identification of heat sources in the rail due to exposure the rolling contact wheel-rail. In the case of the method using one period energy concept it was demonstrated the usefulness of this method to the study of energy processes in the contact wheel-rail under the normal periodic force. The future direction of research is to establish cooperation with research teams entrusted with the diagnostic measurements of track and rolling stock.
PL
Wstęp: Modelowanie matematyczne wspomaga diagnostykę toru i taboru kolejowego, gdyż często z przyczyn technicznych nie jest możliwe uzyskanie pełnego zestawu danych pomiarowych wymaganych do zdiagnozowania deformacji szyny i koła powstałych w wyniku oddziaływania pojazdu szynowego na tor. W diagnostyce toru i taboru kolejowego ważnym zagadnieniem jest badanie skutków kontaktu koła pojazdu i szyny. Badania diagnostyczne toru i taboru kolejowego odgrywają istotną rolę w zapewnieniu bezpieczeństwa przewozów pasażerów i towarów. Celem pracy było opracowanie symulacyjnych sposobów modelowania matematycznego układu koło - szyna kolejowa użytecznych w diagnostyce toru i pojazdu kolejowego. Metody: Przedstawiono i przedyskutowano dwa sposoby modelowania układu koło - szyna kolejowa. Jednym z tych sposobów jest metoda polegająca na sprowadzeniu badanego zagadnienia kontaktowego do zagadnienia polowego i rozwiązaniu zadania identyfikacji źródeł pola w układzie 2-D. Drugim sposobem jest metoda wykorzystująca koncepcję energii jednookresowej. Ten sposób obliczeń został zaadaptowany do modelowania dynamiki kontaktu koło - szyna dla siły normalnej. Wykazano, że opracowane metody modelowania efektywnie wspomagają badania skutków mechanicznych i cieplnych kontaktu koło - szyna oraz przyczyniają się do zapewnienia bezpieczeństwa przewozów. Wyniki i wnioski: W przypadku metody identyfikacji źródeł pola rozpatrzono dwa zagadnienia szczegółowe: zagadnienie skręcania szyny kolejowej oraz dokonano identyfikacji źródeł ciepła w szynie kolejowej spowodowanego kontaktem tocznym koło - szyna. Natomiast w przypadku metody wykorzystującej koncepcję energii jednookresowej wykazano przydatność tej metody do badania procesów energetycznych kontaktu koło - szyna kolejowa pod działaniem siły normalnej o charakterze periodycznym. Przyszłym kierunkiem badań jest praktyczne wykorzystanie opracowanych metod przez nawiązanie współpracy z zespołami badawczymi dokonującymi pomiarów diagnostycznych toru i taboru kolejowego.
3
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Applying information technologies while studying “Numerical Methods and Computer Simulation” section of the “Computer Science and ICT” Middle School Program

84%
MEDVEDEV Y., NIKOLAEVA I., DAVLETYAROVA E.
Edukacja-Technika-Informatyka
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2014
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vol. 5
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issue 2
413-418
EN
The article describes the experience of using information technologies in the study section “Numerical Methods and Computer Simulation” in the subject “Informatics and ICT” primary school. The aims and objectives of the study material in this section on basic and core stages of continuous study of computer science. Consider some examples of the use of information technology in the study of educational material theme “Approximate methods for solving equations with one variable”. To illustrate the results of the research function y = f (x) for solving the equation f (x) = 0, and examples of opportunities for Mathcad charting and determine the roots of the equation. Considered VBA code refinement root of the equation f (x) = 0 by bisection of the interval for the table processor MS Excel. The article summarized the results of testing some educational material section “Numerical Methods and Computer Simulation” in the schools of the city of Vladimir. In the study of educational material in this section, students have the opportunity to conduct an experiment using a computer programming systems, spreadsheets, mathematical computer-aided design Mathcad and other computer software, select the appropriate options, analyze dependencies, predict outcomes, to conduct a graphical interpretation of the results. This contributes to a deeper understanding of the essence of numerical methods and their practical value, focuses on the clever use of computer software applications, and enriches the students’ new ways of solving problems.
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