Technical University of Ostrava

About: Technical University of Ostrava is a education organization based out in Ostrava, Czechia. It is known for research contribution in the topics: Artificial neural network & Evolutionary algorithm. The organization has 4186 authors who have published 8936 publications receiving 65393 citations. The organization is also known as: Vysoká škola báňská – Technická univerzita Ostrava & VŠB – Technical University of Ostrava.

Soil heavy metal pollution and risk assessment associated with the Zn-Pb mining region in Yunnan, Southwest China

Abstract: The environmental assessment and identification of sources of heavy metals in Zn-Pb ore deposits are important steps for the effective prevention of subsequent contamination and for the development of corrective measures. The concentrations of eight heavy metals (As, Cd, Cr, Cu, Hg, Ni, Pb, and Zn) in soils from 40 sampling points around the Jinding Zn-Pb mine in Yunnan, China, were analyzed. An environmental quality assessment of the obtained data was performed using five different contamination and pollution indexes. Statistical analyses were performed to identify the relations among the heavy metals and the pH in soils and possible sources of pollution. The concentrations of As, Cd, Pb, and Zn were extremely high, and 23, 95, 25, and 35% of the samples, respectively, exceeded the heavy metal limits set in the Chinese Environmental Quality Standard for Soils (GB15618-1995, grade III). According to the contamination and pollution indexes, environmental risks in the area are high or extremely high. The highest risk is represented by Cd contamination, the median concentration of which exceeds the GB15618-1995 limit. Based on the combination of statistical analyses and geostatistical mapping, we identified three groups of heavy metals that originate from different sources. The main sources of As, Cd, Pb, Zn, and Cu are mining activities, airborne particulates from smelters, and the weathering of tailings. The main sources of Hg are dust fallout and gaseous emissions from smelters and tailing dams. Cr and Ni originate from lithogenic sources.

A survey on evolutionary algorithms dynamics and its complexity – Mutual relations, past, present and future

Abstract: Swarm and evolutionary based algorithms represent a class of search methods that can be used for solving optimization problems. They mimic natural principles of evolution and swarm based societies like ants, bees, by employing a population-based approach in mutual communication and information sharing and processing, including randomness. In this paper, history of swarm and evolutionary algorithms are discussed in general as well as their dynamics, structure and behavior. The core of this paper is an overview of an alternative way how dynamics of arbitrary swarm and evolutionary algorithms can be visualized, analyzed and controlled. Also selected representative applications are discussed at the end. Both subtopics are based on interdisciplinary intersection of two interesting research areas: swarm and evolutionary algorithms and complex dynamics of nonlinear systems that usually exhibit very complex behavior.

Effect of potassium in calcined Co–Mn–Al layered double hydroxide on the catalytic decomposition of N2O

Abstract: A series of catalysts was prepared by thermal treatment (500 °C) of the coprecipitated Co–Mn–Al layered double hydroxide (Co:Mn:Al molar ratio of 4:1:1) doped with various amount of potassium (0–3 wt%). Obtained spinel-like mixed oxides were characterized by powder X-ray diffraction, X-ray photoelectron spectroscopy, BET surface area measurements, temperature-programmed H 2 reduction, and temperature-programmed CO 2 and NH 3 desorption. The prepared catalysts were tested for N 2 O decomposition to determine the effect of K addition on the catalytic activity in the presence of O 2 , NO x and H 2 O. An optimum K content of ca. 0.9–1.6 wt% was found to achieve a high catalytic activity in the presence of O 2 and H 2 O, while the non-modified Co–Mn–Al mixed oxide was the most active catalyst in the presence of O 2 and NO x . The addition of potassium to the Co–Mn–Al mixed oxide apparently results in a modification of both electronic properties of active metals and acid-base function of the catalyst surface.