Analysis and Model of Corrosion Wear of Selected Materials Used in Special Vehicles

The paper deals with the evaluation and modelling of corrosion wear of two standard materials used in the construction of special vehicles. The experimental research on corrosion wear involved the testing of two steels, EN 10131 and EN C22R, in a salt spray at 35 and 50 oC for 24, 48, 120 and 144 hours. The model of the process of corrosion degradation of the tested materials uses the results of weight loss of the samples as a function of temperature and exposure time. The diagnostic macroscopic evaluation of corroded surfaces of the tested materials, using graphic (analogue) information of surfaces and its conversion into the digital form, is a completely new technology. The samples were photographed using a CCD camera, then pre-processed, segmented, and masks were created for the logic of deciding what corrosion is and what it is not. The final filtered image was created in binary values where logic 1 refers to a corroded and logic 0 to a non-corroded sample. The MATLAB software environment and the Image Processing Toolbox were used to process the results of the surface evaluation

Noise Reduction in the Cab of a Special Vehicle

Noise is highly associated with adverse effects on health, the human psyche and performance. Current special vehicles do not possess sufficient technologies to suppress the transmission of noise or vibration, which typically results in loss of control, comfort, driving safety, the performance of tasks, etc. At the same time, noise reduces attention and work efficiency while increasing fatigue, leading to hazards, dangerous situations, and missions that may not be completed. This article briefly presents selected parts of a project which included additional soundproofing of a special armoured mobile vehicle on a TATRA wheeled chassis. Basic theoretical, experimental, and practical information about this project is presented. To reduce noise, a selected damping material was used, which is a combination of recycled PUR foam and black rubber with a rough structure. The damping material was selected based on repeated experimental testing of sound absorption measurements from several damping materials. The material was chosen for suitable damping effects and corresponding technological properties (resistance to high temperatures, non-flammability, etc.). In the engine compartment and the cab of the vehicle, the damping properties were experimentally verified after retrofitting, while the noise was significantly reduced

MODELLING OF EROSION EFFECTS ON COATINGS OF MILITARY VEHICLE COMPONENTS

Military and flying machines (vehicles, aircraft, etc.) operate in extreme conditions and require appropriate measurements to improve the durability of all systems and materials in their subsystems. Protective coatings usually perform this function with great success. One of the most pressing needs for change military vehicles is the development of high performance coatings for erosion protection of military machine components (turbine, engine, compressor, turbocharger, intercooler components, etc.). The approach presented in this article is based on the use of computer simulation techniques to model the coating behaviour in simulated erosion conditions. Shear stress and equivalent plastic strain at the coating/substrate interface were used as criteria describing the coating response to particle impact. This article deals with preliminary modelling results, in terms of selecting a range of material properties (internal layers thickness and stress or strain) and the coating structure

Northern Riffleshell and Clubshell 2015 Monitoring Results

In 2015, staff from the Illinois Natural History Survey continued to monitor translocated populations of two federally-endangered freshwater mussel species in the Vermilion River basin (Wabash River drainage). Between 2010 and 2014, a total of 2,099 Northern Riffleshell (Epioblasma rangiana) and 1,766 Clubshell (Pleurobema clava) have been translocated to eight sites in the Vermilion River basin, Champaign and Vermilion counties, Illinois. These translocated animals have been monitored seasonally since being moved to Illinois. For the 2015 calendar year, 36% (716) of the 1,991 available Northern Riffleshell were encountered, and of those physically examined, 61% (54 of 88) were alive. Conversely, 77% (1,359) of the 1,758 available Clubshell were encountered, and of those examined, 82% (106 of 129) were alive. The encounter and survival rates from the raw data collected in 2015 were comparable to previous years in Illinois. Throughout the duration of the project, both Northern Riffleshell and Clubshell have had higher encounter rates in the spring and autumn than summer. This relocation project is being funded, in part, by a natural resource damage assessment settlement (Hegeler Zinc—Lyondell Basell Companies) to the U.S. Fish and Wildlife Service and to the State of Illinois, and by the U.S. Fish and Wildlife Service’s Ohio River Basin Fish Habitat Partnership.IDNR Division of Natural HeritageU.S. Fish & Wildlife Serviceunpublishednot peer reviewe

Determination of the Mechanical Properties of Weld Materials based on Hardness Test

Práce se zabývá stanovováním mechanických vlastností materiálu na základě provedené instrumentované zkoušky tvrdosti. Podnětem k této práci byla smlouva o výzkumném projektu mezi ÚAM Brno, s.r.o. a společností ČEZ, a.s., kdy úkolem bylo vyvinout metodiku vyhodnocování změny mechanických vlastností pomocí NDT metody. Z těchto důvodů je vyvíjení metodiky zaměřeno především pro použití v praxi se zaměřením na určování mechanických vlastností heterogenního svarového spoje v provozu. Mechanické vlastnosti materiálu jsou určovány pomocí provedení nedestruktivního instrumentovaného měření tvrdosti dle Vickerse. Vyvíjená metodika pro stanovení základních mechanických vlastností je založena na principu inverzního modelování instrumentovaného měření tvrdosti metodou konečných prvků, kdy výstupem je indentační křivka a změřený povrch vtisku po odlehčení. Porovnáváním výstupů z experimentálního instrumentovaného měření tvrdosti a výstupů z modelované zkoušky tvrdosti pomocí MKP je dosaženo základních mechanických vlastností materiálu.This dissertation thesis deals with determination of the mechanical properties of weld materials based on instrumented hardness test. This work was caused by the research project between IAM Brno Ltd and CEZ corp., when the task was to develop a methodology for evaluation of mechanical material properties using NDT methods. For these reasons the development of methodology is reflected especially for use in practice focusing to determining the mechanical properties of the heterogeneous weld joint on the assembled equipment. The mechanical material properties are determined by carrying out non-destructive tests of the instrumented Vickers hardness. The developed methodology for determining of basic mechanical properties is based on the principle of inverse FEM modeling of the instrumented hardness tests, when output of the testing is indentation curve and measured surface imprint after unloading. The basic material mechanical properties are achieved by comparing the outputs of the experimental instrumented hardness tests and the outputs of the modeled hardness test using FEM.

Computer-aided method of analytic surfaces modelling

V první části se práce zabývá projekcí bodů z Euklidova prostoru do roviny a zobrazením takto vzniklých rovinných bodů na počítači. Druhá část se zaměřuje na diskretizaci analyticky zadané plochy. To je její aproximace sítí bodů, které díky předchozí části dokážeme zobrazit na počítači. Třetí část se věnuje obarvení plochy různými typy výplně. Nakonec je přidáno softwarové řešení.The first part of the thesis deals with projections of points from an Euclidean space into a plane and displaying of the resulted planar points on a computer. The second part focuses on a discretization of analytically specified surfaces. This is an approximation with network points. Due to the previous part, we are able to display them on a computer. The third part is dedicated to various types of coating fillings. Finally, the software solution is added.

Information ecology and the concept of information

In the paper, the author presents that information ecology can be considered to be a theoretical reaction on the inquiry into the character of the concept of information, especially on the solving of so called Capurro's trilema. The trilema consists in the answering the question of whether information is an univocal, analogical, or equivocal concept. In the paper, there is introduced what does univocity, analogy and equivocity of the concepts mean and there is presented some conceptions according to which the concept of information is considered to be an univocal, analogical and equivocal concept. There is also shown that a development of information ecology is possible only if we could consider information to be an analogical concept.Článek se zabývá vztahem informační ekologie k pojmu informace

Proficient replication of the yeast genome by a viral DNA polymerase

DNA replication in eukaryotic cells requires minimally three B-family DNA polymerases: Pol α, Pol δ, and Pol ϵ. Pol δ replicates and matures Okazaki fragments on the lagging strand of the replication fork. Saccharomyces cerevisiae Pol δ is a three-subunit enzyme (Pol3-Pol31-Pol32). A small C-terminal domain of the catalytic subunit Pol3 carries both iron-sulfur cluster and zinc-binding motifs, which mediate interactions with Pol31, and processive replication with the replication clamp proliferating cell nuclear antigen (PCNA), respectively. We show that the entire N-terminal domain of Pol3, containing polymerase and proofreading activities, could be effectively replaced by those from bacteriophage RB69, and could carry out chromosomal DNA replication in yeast with remarkable high fidelity, provided that adaptive mutations in the replication clamp PCNA were introduced. This result is consistent with the model that all essential interactions for DNA replication in yeast are mediated through the small C-terminal domain of Pol3. The chimeric polymerase carries out processive replication with PCNA in vitro; however, in yeast, it requires an increased involvement of the mutagenic translesion DNA polymerase ζ during DNA replication