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A progressive type of tungsten-doped DLC coating was applied to a quenched and tempered 100Cr6 steel with the aim to improve the wear and corrosion properties in simulated seawater conditions and to compare the performance to conventional DLC coating. Tungsten doping caused a shift of the corrosion potential (Ecorr) to a lower negative value of −172 mV, while the conventional DLC exhibited an Ecorr of −477 mV. In dry conditions, the W-DLC coefficient of friction is slightly higher than that of the conventional DLC (0.187 for the W-DLC vs. 0.137 for the DLC), but in cases of a saltwater environment, this difference becomes almost negligible (0.105 for the W-DLC vs. 0.076 for the DLC). The conventional DLC coating also started to show marks of deterioration when exposed to a combination of wear in a corrosive environment, while the W-DLC layer still maintained its integrity.

A surface treatment process, composed of plasma electrolytic oxidation (PEO) and sealing by temporary oil preservation system containing corrosion inhibitors, was performed on AZ31 magnesium alloy in order to improve its corrosion resistance in environments containing chlorides. Both atmospheric and immersion conditions were evaluated by electrochemical tests in 0.1M NaCl solution together with salt spray test according to STN EN ISO 9227 standard. The obtained results confirmed significant improvement of corrosion resistance reached by the PEO sealing in aggressive environments compared to the pure PEO coating on AZ31 surface. Hence, such a duplex coating is a very perspective alternative for magnesium alloy applications in severe conditions or for temporary protection of magnesium products coated by the PEO during marine transport.

High strength low alloy (HSLA) steels are a new generation of plain carbon steels with significantly improved mechanical properties while maintaining good weldability with common commercial techniques. Residual stress and microstructural analysis of welded HSLA Strenx 700 MC was carried out in this research. Results have shown that the welding process causes significant grain coarsening in the heat affected zone. The microstructural changes are also accompanied with creation of tensile residual stress field in the weld metal and heat affected zone, reaching up-to depth of 4 mm. Tensile residual stresses are well known for acceleration of fatigue crack initiation and together with coarse grains can lead to significant decrease of the fatigue properties of the welded structure.

In order to increase the corrosion resistance of magnesium alloy AZ91 in corrosion environments containing chlorides, the alloy surface has been modified by plasma electrolytic oxidation (PEO). The chemical composition of electrolyte in the PEO process consisted of 12 g/L Na3PO4·12 H2O and 1 g/L KOH, and a direct current was applied to the sample. The corrosion resistance of PEO coating and as-cast AZ91 (sample without PEO coating) was assessed using two different electrochemical methods: electrochemical impedance spectroscopy (EIS) and potentiodynamic polarisation (PDP) in 0.1 M NaCl at laboratory temperature. In addition to the electrochemical methods, the morphology of the oxidic coating was observed in the cross-sectional and top surface view by using the SEM technique. For better determination of the microstructure and PEO coating, chemical composition EDX analysis was used. The results of the experiments show that the formation of the PEO coating on AZ91 alloy has a more positive effect on the corrosion resistance in 0.1 M NaCl based on electrochemical methods than in the case of the formed coating on AZ31 alloy from the previous study. Based on electrochemical measurements in the selected environment, the formation of PEO coating on AZ91 was accompanied by a significant increase in polarisation resistance after short-term exposure compared to the as-cast surface. The EIS results showed a 73 times higher Rp value for PEO coated AZ91 when compared to the as-cast AZ91. Correspondingly, a 27 times lower icorr value was observed for PEO coated AZ91 than in the case of substrate AZ91 in 0.1 M NaCl. At the same time, the typically porous and inhomogeneous structure of the formed PEO coating on the magnesium alloy AZ91 was demonstrated.

A phosphating process modified for a high-strength low-alloy (HSLA) steel was performed at various temperatures and influence on the surface properties of the Domex steel covered by manganese phosphate (MnP) was investigated by electrochemical corrosion tests supported by a photo documentation performed by the SEM. Corrosion measurements were performed in 0.1M NaCl solution at 22±2 °C using electrochemical impedance spectroscopy and potentio-dynamic polarisation in order to obtain thermodynamic and kinetic corrosion characteristics and individual elements of equivalent circuits. It is that a temperature of the phosphating process has a very significant effect on protection properties of the created manganese phosphate coating on the Domex steel and needs to be strictly monitored. According to results of corrosion testing and surface morphology observations, the optimal temperature for the phosphating process on the tested Domex steel was chosen.

Wrought AZ31 magnesium alloy was used as the experimental material for fluoride conversion coating preparation in Na[BF4] molten salt. Two coating temperatures, 430 °C and 450 °C, and three coating times, 0.5, 2, and 8 h, were used for the coating preparation. A scanning electron microscope and energy-dispersive X-ray spectroscopy were used for an investigation of the surface morphology and the cross-sections of the prepared coatings including chemical composition determination. The corrosion resistance of the prepared specimens was investigated in terms of the potentiodynamic tests, electrochemical impedance spectroscopy and immersion tests in the environment of simulated body fluids at 37 ± 2 °C. The increase in the coating temperature and coating time resulted in higher coatings thicknesses and better corrosion resistance. Higher coating temperature was accompanied by smaller defects uniformly distributed on the coating surface. The defects were most probably created due to the reaction of the AlxMny intermetallic phase with Na[BF4] molten salt and/or with the product of its decomposition, BF3 compound, resulting in the creation of soluble Na3[AlF6] and AlF3 compounds, which were removed from the coating during the removal of the secondary Na[MgF3] layer. The negative influence of the AlxMny intermetallic phase was correlated to the particle size and thus the size of created defects.

IoT and their industrial implementation aimed at Industry 4.0 is of a major interest among both research and development professionals. This article deals with the modifications and extensions possibilities of the standard MicroPython implementation on the STM32 platform, as well as the use in the development, implementation and programming of IoT peripherals, creation of custom libraries and custom modules at the hardware level. Discussed are the essentials associated with the development of general IoT application and the MicroPython environment, as a tool for rapid-prototyping of such applications. Portability is ensured thanks to the intensive utilization of HAL (Hardware Abstraction Layer) technology, which allows usage across the entire spectrum of devices with ported MicroPython. Modularity, scalability and extendibility of the application are demonstrated in examples, where the connection of a common LM92 temperature sensor, the control of a microcontroller pin and a DDS (Direct Digital Synthesis) generator are shown.

The ever more pressing and concurrent requirements of light design, increased performances and reliability, energy savings together with acceptable costs, is always pushing researchers and engineers toward the definition and application of new materials and treatments, able to guarantee superior properties and adequate repeatability and reliability. This means that one step beyond the definition of a potentially successful solution, a complete characterization of the new materials is needed, in order to get the right data and use them in the design process. A promising severe plastic deformation surface treatment to improve the fatigue properties of materials and metal parts is considered in this paper. The used treatment is called the severe shot peening, and it is derived from the conventional shot peening but with use of unusually high peening parameters. It was proven that it is able to generate a nanostructured surface layer of material, which results in superior fatigue properties when applied to many structural materials. The severe shot peening is applied to an AW 7075 Al alloy, widely used in mechanical and aeronautic constructions and the effects of such a treatment on this material are investigated in this paper, with particular emphasis on the ultra-high-cycle fatigue behavior. The results address the choice of the correct treatment parameters for getting an evaluable advantage of this treatment and are critically discussed for a complete understanding of the mechanisms leading to the modified fatigue behavior, in view of the future developments and research in the field.

At the present time, the usage of optical microscopy allows extension of aggregate surface texture detection methods. Three-dimensional data outputs of the aggregate particles can be obtained by these methods and provide additional opportunities in the field of texture evaluation. In this paper, the new approach for quantification of aggregate particle texture is described. Aggregate particles with different texture were scanned by the stereomicroscope and the data files with three-dimensional information were exported. The MicroSYS program was developed to determine new three-dimensional texture evaluating parameter. The Z-plane volume difference characteristic represents aggregate surface texture as a percentage difference between two volumes (aggregate volume and wrapping volume).

Developed road infrastructure is a very significant factor which is influencing and conditioning the development of the economy and quality of transportation. Increasing demands for quality of road infrastructure lead to the construction of new roads. Moreover, the importance of keeping pavements in good condition increases proportionately with the increasing traffic. The construction of the road communications, their management and maintenance are material and energy consuming and the problem with the availability and exhaustion of resources is accretive. However, the development of road construction have to respect the protection of the environment, it have to be controlled and sustainable. Sustainable development ensures to meet subsistence for today’s and future generations and respects the natural functions of ecosystems. The paper is focused on the analysis of the factors arising from the production of asphalt mixtures for road infrastructure by asphalt mixing plants and their subsequent impact on the environment.

Effective road management requires the constant generation of new approaches. It is our duty to focus on improving all technical and process areas of road management, especially in the context of environmental and economic sustainability. Otherwise, we will face the fact that neglected parts will slow down the progress of the whole system. This will be reflected in a reduction in the quality of the infrastructure and increased costs over its life cycle. The approach must be systematic and therefore it is necessary to address the elements that, at first sight, do not have a major impact on other elements contained in the whole structure of road infrastructure management. One of the key areas for improvement is the process of winter road maintenance. It must reflect global climate change, new approaches to the cost-effectiveness of finances spent by users and road managers and, last but not least, the need for modern and safe mobility of goods and people. Advanced technologies such as automated anti-icing spraying systems or predictive monitoring of road structure temperature development are one example. However, these innovations bring not only positive but also negative effects.

In general, it can be presentedthat winter road maintenance costs are rising due to increasing mobility, rising of salaries,and technologicalneeds. For this reason, it is necessary to bring innovations intothese processes. The greatest space is in the area of weather forecasting, which is a trigger for maintenance activities in the form of reducing black iceor snow removal. Roadadministrators use predictive services as a standard to obtain critical atmospheric temperature and weather data in advance. From the point of view of transport safety, the need to obtain predictive temperature data on the road surface is also important. These must also be obtained largely by knowing the temperature trends inside the road structure. The article presents the direction of our own research activities, whereas it focuses on the philosophy of research, justification of the idea, the introduction of research procedures,and the presentation of partial results.

The surface texture of aggregate particles was investigated based on the 3D model of surface generated from the measurements by optic microscope. New software MicroSYS was developed to determine the wrapping plane of 3D model of aggregate using the function called “Thin plate spline“. New parameter for evaluation of surface texture of aggregate particle was proposed as the volumetric difference between two planes (wrapping plane and aggregate surface). Applicability of this parameters was tested on two aggregate fractions (4/8 and 8/11) coming form 11 quarries in Slovakia. The tested aggregates differed from petrography point of view and ranged from soft to hard. The difference among the quarries and also between fractions of aggregate was found out. The better surface texture was observed for the finner fraction of aggregate. Simultaneously, the better results were determined in the case of aggregate produced from the ingeous intrusive or extrusive rocks comparing to the sedimentary carbonate rocks aggregate.

Intelligent buildings are productive, energy efficient and environmentally acceptable. Intelligent buildings should be health, permanent and technologically advanced. It is necessary to predict the development and selection of suitable systems for the thermal comfort for ensure of the thermal comfort in the workplace. It is important to analyse how many thermal factors will affect the population, room temperature uniformity, asymmetry of the radiation temperature and turbulence intensity of the flowing air. Thermal comfort is given by the radiant heat, air temperature, air velocity and relative humidity in the room. The main impact of these factors on the comfort level of individuals depends on the type of clothing and on activity. The wrong thermal comfort is detrimental to workers’ health, affects adverse effects on the psyche and increasing the risk of accidents. The thermal comfort of people can be achieved by intelligent management of energy systems in the buildings. The measurement results and settings of intelligent systems are presented in this article.

One of the basic safety requirements on roadways is the skid resistance. It plays very important role especially during wet and rainy conditions. It is a pavement surface characterization which describes interaction between vehicle wheel and road surface. Mainly insufficient skid resistance or its complete loss is a reason of slippery roads and therefore risk of traffic accidents rises. The article is concerned with examining varying values of skid resistance on selected long-time monitored road parts with different asphalt wearing courses in Slovakia.

The article is concerned about the evaluation of aggregate microtexture. It is very important parameter from the traffic safety point of view and is described as a configuration of small irregularities on the aggregate surface. The new evaluating approach of aggregate microtexture based on the 3-D method is described in this article. 3-D model of surface of aggregate particle was generated from the measurements by microscope method. New program was developed for quantification of aggregate microtexture by a volumetric characteristics. Usability of this method was tested on samples of two coarse aggregate fraction taken from the eleven different quarries in Slovakia. The results of this evaluation have shown a high variability of values of volumetric characteristics between the fractions of aggregate and also between quarries.

The paper focuses on the issue of the use of three-dimensional mobile mapping system and the following processing of obtained data. The first part is devoted to the description of the three-dimensional mobile mapping technology using LiDAR, specifically to the mobile three-dimensional scanner - Lynx SG1 from Teledyne OPTECH. It describes into more details the process of works from the field data collection to their so called "postprocessing" as well as a variety of output options and interpretations of results obtained in the measurements. Advantages of the system together with its limits of use are summarized in the conclusion of the research paper.

The microtexture of asphalt pavement surface is an essential parameter from the traffic safety point of view and it closely relates to a geometrical, petrological and physical properties of aggregate particle used in asphalt pavement. Microtexture has a significant influence for assurance basic friction values between tire and pavement in relation to a skid resistance properties. Therefore, the microtexture detecting methods are necessary. The British pendulum tester measurements have been carried out on selected sections of roads with different asphalt surfaces. Individual grains of aggregates were taken from the surface of each section from the sliding path and also from the core sample after the extraction. The laboratory profilometry measurements have been practiced on these aggregate samples and subsequently the surface microtexture was investigated based on commonly used texture characteristics and the filtration approach was applied in calculation process. The results have shown the degradation of microtexture values occurs due to polishing of aggregate under loading from traffic in relation to the type of used aggregate. Some correlation between BPN values and texture characteristics was found.

At the present time, a lot of laboratory measurement and evaluation approaches exist for investigation of aggregate texture, which is necessary to assecurate a basic level of friction between tire and asphalt pavement. In this contribution, two laboratory methods based on three dimensional and two dimensional analyses of aggregate texture investigation are presented. The values of three dimensional texture parameter were compared with the values of the two dimensional texture parameters. The measurements by both these methods were performed on the same grains of aggregates. Three dimensional evaluation outputs were obtained from measurement by optical microscope method and two dimensional evaluation outputs were obtained from measurement by profilometry method. All of analyzed aggregate texture parameters (three dimensional and two dimensional) give information about texture depth and therefore can be compared to each other. Parameters of regression and correlation analysis were used to find relation between the three dimensional and two dimensional texture parameters and obtained results were analyzed and discussed.

Asphalt pavement micro texture values primarily depend on aggregate properties used in asphalt pavement mixture and by aggregate surfaces is secured the basic contact medium with vehicle tires. It often happens that new asphalt surfaces have not required skid resistance properties and is needed a certain period of time to eliminate film of bitumen binder which is coating the aggregate grain on the surface of pavement by action of vehicles. In most cases, the investigation of the aggregate micro texture impact on the pavement skid resistance properties is carried out under laboratory conditions and generally relates only to measurements on natural aggregate samples (without bitumen). However, due to coating of aggregate by bitumen binder, valleys between the individual peaks of aggregate are filled. Obviously, it can be supposed that the usage of high amount of bitumen content can leads to decreasing of aggregate micro texture values. From this point of view, it can be expected that change in micro texture values depends on the content of binder in the asphalt mixture. Particular aggregate grains were taken from asphalt mixtures samples (AC 8, AC 11 and SMA 11) produced in the laboratory, in order to determine the impact of aggregate coating by bitumen binder on micro texture change. Each usage asphalt mixture was produced with three different bitumen binder contents. Digital image analysis method was used for subsequent evaluation. Changes in the micro texture values depending on the amount of used bitumen binder and also on the calculated theoretical bitumen film thickness are investigated in the conclusion.