Studie týkající se návrhu hnacího napínacího systému pásového dopravníku s vysokým výstupním výkonem kladky

The main component of the conveyor is the rubber mat, which, driven through specific methods, ensures the transport of the excavated mass. The use of this type of transportation at optimal parameters depends on the correct stretching (tensioning) of the rubber mat. This is achieved with the help of a stretching gear with carriage (jointed to the stretching drum) with engine - driven cable.Hlavní složkou dopravníku je gumová podložka, řízená specifickou metodou, zajišťující dopravu vytěžené hmoty. Používání tohoto druhu dopravy při optimálních parametrech závisí na správném napětí gumové podložky. Toho je možné dosáhnout pomocí napínacího zařízení (připevněno na napínacím bubnu) s motorem - řízený kabelem

Porovnávací studie klasické metody a metody založené na analýze metody konečných prvků deformací a napětí brzdového věnce

In this paper are present/exists two methods of gravel rim’s tensions and deformations under the pressure effect created of shoe-brake in the brake process. The first method so called the classic one has at the bottom of it known theory’s from the discipline frame the material resistance and the second method has at the bottom of it the gravel with the finite elements help. Both methods presented are applied at the brakes with miner hoisting machines.V tomto článku jsou prezentovány 2 metody analýzy napětí a deformací brzdového věnce pod zatížením vytvořeným nožní brzdou při brzdění. První metoda, nazývaná klasická, má za základ ve známé teorii z odporu materiálu a základem druhé je metoda konečných prvků. Obě metody jsou aplikované na brzdách u hornických těžebních strojů

ECONOMETRIC MODELING OF GDP BY EMPLOYMENT AND THE VALUE OF TANGIBLE FIXED ASSESTS

The economic potential of a country is consistently a primary goal of existence and sustainable development, to ensure the livelihood of all residents, increase living standards. To achieve this major goal rigorous study must be complex to formulate a diagnosis and real economic status and rationale, on the basis of economic and legislative policy decisions, decisions addressing both immediate time horizons as well as longer periods of time. In this context, we analyzed dynamics of GDP according to the dynamics of employment and dynamics of tangible fixed assets of the economy by applying a rigorous econometric modeling methodology

Macrostabilization of the Migration Phenomenon

Abstract: Labour migration is a present phenomenon in the European Union. This phenomenon takes over the entire European continent, but especially in the EU countries. The labor market in Europe is increasingly affected by population aging. Economic differences between European countries make workforce in developing countries to move to developed countries where they find it easier to work and receive higher remuneration than in their home countries. This article tracks labor migration from/to EU, employment in Romania and Romanian migration towards the countries of Western Europe. It also presents statistics on labor migration in the EU and its impact on the labor market

Ingestion of Polyvinylchloride Powder Particles Induces Oxidative Stress and Hepatic Histopathological Changes in <i>Oreochromis niloticus</i> (Nile Tilapia)—A Preliminary Study

Plastic debris is considered an emerging aquatic pollutant as an alarming number of reports are indicating the environmental contamination with such agents. Ichthyofauna has been subjected to increasing plastic pollution over the past years, which has led to detrimental effects in the food chain, and consequently to the general health of ecosystems. In this study, we exposed juvenile specimens of Oreochromis niloticus to polyvinyl chloride (PVC) in powder form. Specimens and water parameters were closely monitored for 40 days before tissue samples were collected for histological and biochemical analysis. Structural hepatic alterations were observed in specimens from the exposed groups, such as intercellular corridors, dilation of sinusoidal capillaries, hyperchromatic nuclei, nuclear hypertrophy, and cytoplasm vacuolization. Low catalase activity was observed in the case of 1000 mg of PVC/kg feed group, as well as high levels of malondialdehyde compared to the control group, indicating oxidative stress. Glutathione peroxidase activity was also significantly decreased in the 500 and 1000 mg/kg feed group compared to the control group. These findings suggest that a midterm exposure to PVC particles can significantly affect the activity of antioxidative enzymes in O. niloticus specimens and induce changes of hepatic tissue structure