Lead-acid baterry charger with automatic cycle

Olověné akumulátory jsou i v 21.století stále významným a hojně využívaným typem akumulátorů. Tato práce se proto věnuje návrhu inteligentního nabíječe, který zajistí jejich rychlé, ale šetrné nabití s ohledem na maximální životnost a spolehlivost. Navržený systém využívá metody nabíjení konstantním proudem i konstantním napětím. Lze jej použít k nabíjení klasických, gelových i trakčních akumulátorů s pracovním napětím 12 V. Dokáže šetrně nabíjet hluboce vybité akumulátory, ale i udržovat jejich maximální kapacitu při delší odstávce. Nabíječ je schopen rozeznat míru vybití akumulátoru a podle ní automaticky zvolit nejvhodnější nabíjecí proces. Jednotlivé nabíjecí fáze jsou interpretovány pomocí světelné signalizace a dosažitelný nabíjecí proud činí 20 A.The lead-acid batteries are still important and very often used type of battery even in 21st century. This project is focused on development of charger, which provides fast, but save charging of batteries with respect to maximum life time and reliability. The developed system uses constant current charging and constant voltage charging methods. It's specialized in charging batteries with liquid or gel electrolyte and traction types of batteries, which works with 12 V value of voltage. It's able to charge safely the deeply discharged batteries and when battery is unpluged for a long time, it can keep its capacity at maximum level too. The charger can choose optimal charging process according to the discharged level of battery. Each charging phase is interpreted by light signals and the achievable charging current is 20 A.

WOFEX 2021 : 19th annual workshop, Ostrava, 1th September 2021 : proceedings of papers

The workshop WOFEX 2021 (PhD workshop of Faculty of Electrical Engineer-ing and Computer Science) was held on September 1st September 2021 at the VSB – Technical University of Ostrava. The workshop offers an opportunity for students to meet and share their research experiences, to discover commonalities in research and studentship, and to foster a collaborative environment for joint problem solving. PhD students are encouraged to attend in order to ensure a broad, unconfined discussion. In that view, this workshop is intended for students and researchers of this faculty offering opportunities to meet new colleagues.Ostrav

Heat Input Influence on the Fatigue Life of Welds from Steel S460MC

Fine-grained steels belong to the progressive materials, which are increasingly used in the production of welded structures subjected to both static and dynamic loads. These are unalloyed or microalloyed steels hardened mainly by the grain-boundary strengthening mechanism. Such steels require specific welding procedures, especially in terms of the heat input value. At present, there are studies of the welding influence on the change of thermomechanically processed steels’ mechanical properties, however mainly under static loading. The paper is therefore focused on the assessment of the welding effect under dynamic loading of welded joints. In the experimental part was determined the influence of five different heat input values on the change of weld fatigue life. As a result, there is both determination of five S-N curves for the double-sided fillet welds from the thermomechanically processed fine-grained steel S460MC and the quantification of the main influences reducing the fatigue life of the joint

On Using The Probabilistic Approach To Synthesis Of Logical Circuits With Low Power Consumption

The problem of state assignment of a discrete automaton aimed to decreasing the switching activity of memory elements in the implemented circuits is considered. To solve this problem the probabilities of transitions between states of the automaton is taken into account

Effect of Higher Silicon Content and Heat Treatment on Structure Evolution and High-Temperature Behaviour of Fe-28Al-15Si-2Mo Alloy

This paper describes the structure and properties of cast Fe3Al-based alloy doped with 15 at. % of silicon and 2 at. % of molybdenum. The higher content of silicon is useful for the enhancement of high-temperature mechanical properties or corrosion resistance of iron aluminides but deteriorates their workability due to increased brittleness. It was found that the presence of both alloying elements leads to an increase of values of the high-temperature yield stress in compression. The heat treatment (annealing at 800 degrees C for 100 h) used for the achievement of phase stability causes the grain coarsening, so the values of the high-temperature yield stress in compression are lower at 600 degrees C and 700 degrees C in comparison to values measured for the as-cast state. This stabilization annealing significantly improves the workability/machinability of alloy. Furthermore, the higher silicon content positively affects the values of the thermal expansion coefficient that was found to be lower in the temperature range up to 600 degrees C compared to alloys with lower content of silicon

Number Concentrations and Modal Structure of Indoor/Outdoor Fine Particles in Four European Cities

Indoor/outdoor aerosol size distribution was measured in four European cities (Oslo-Norway, Prague-Czech Republic, Milan-Italy and Athens-Greece) during 2002 in order to examine the differences in the characteristics of the indoor/outdoor modal structure and to evaluate the effect of indoor sources to the aerosol size distributions. All the measurement sites were naturally ventilated and were occupied during the campaigns by permanent residents or for certain time periods by the technical staff responsible for the instrumentation. Outdoor particle number (PN) concentrations presented the higher values in Milan and Athens (median values 1.4 x 10(4) # cm(-3) and 2.9 x 10(4) # cm(-3) respectively) as a result of elevated outdoor emissions and led to correspondingly higher indoor values compared to Oslo and Prague. In absence of indoor activities, the indoor concentrations followed the fluctuations of the outdoor concentrations in all the measurement sites. Indoor activities (cooking, smoking, etc.) resulted in elevated indoor PN concentrations (maximum values ranging between 1.7 x 10(5) # cm(-3) and 3.2 x 10(5) # cm(-3)) and to I/O ratios higher than one. The I/O ratios were size dependant and for periods without indoor activities, they presented the lowest values for particles <50 nm (0.51 +/- 0.15) and the ratios increased with fine particle size (0.79 +/- 0.12 for particles between 100-200 nm). The analysis of the modal structure showed that the indoor aerosol size distribution characteristics differ from the outdoors under the effect of indoor sources. The percentage of unimodal size distributions increased during indoor emissions, compared to periods without indoor sources, along with the number concentration of Aitken mode particles, indicating emissions in specific size ranges according to the type of the indoor source.Peer reviewe

Inhalation of ZnO nanoparticles: Splice junction expression and alternative splicing in mice

Despite the wide application of nanomaterials, toxicity studies of nanoparticles (NP) are often limited to in vitro cell models, and the biological impact of NP exposure in mammals has not been thoroughly investigated. Zinc oxide (ZnO) NPs are commonly used in various consumer products. To evaluate the effects of the inhalation of ZnO NP in mice, we studied splice junction expression in the lungs as a proxy to gene expression changes analysis. Female ICR mice were treated with 6.46 x 10(4) and 1.93 x 10(6) NP/cm(3) for 3 days and 3 months, respectively. An analysis of differential expression and alternative splicing events in 298 targets (splice junctions) of 68 genes involved in the processes relevant to the biological effects of ZnO NP was conducted using next-generation sequencing. Three days of exposure resulted in the upregulation of IL-6 and downregulation of BID, GSR, NF-kB2, PTGS2, SLC11A2, and TXNRD1 splice junction expression; 3 months of exposure increased the expression of splice junctions in ALDH3A1, APAF1, BID, CASP3, DHCR7, GCLC, GCLM, GSR, GSS, EHHADH, FAS, HMOX-1, IFN, NF-kB1, NQO-1, PTGS1, PTGS2, RAD51, RIPK2, SRXN1, TRAF6, and TXNRD1. Alternative splicing of TRAF6 and TXNRD1 was induced after 3 days of exposure to 1.93 x 10(6) NP/cm(3). In summary, we observed changes of splice junction expression in genes involved in oxidative stress, apoptosis, immune response, inflammation, and DNA repair, as well as the induction of alternative splicing in genes associated with oxidative stress and inflammation. Our data indicate the potential negative biological effects of ZnO NP inhalation.Web of Science168120019

Concept Lattice Generation by Singular Value Decomposition

Abstract. Latent semantic indexing (LSI) is an application of numerical method called singular value decomposition (SVD), which discovers latent semantic in documents by creating concepts from existing terms. The application area is not limited to text retrieval, many applications such as image compression are known. We propose usage of SVD as a possible data mining method and lattice size reduction tool. We offer in this paper preliminary experiments to support usability of proposed method