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Abstract

Automatic detection of objects is a part of visual systems supporting a quality control system of a manufacturing process. The paper concerns the influence of the resolution of images and the size of detected objects in pixels on measurements results. Test images of the objects of a known size were generated. The values of the perimeter of the objects were compared to the obtained values of measurements on the images with degraded resolution. The process of the degradation of the references images by successive downsizing the resolution, detection and measurements were performed applying automatic algorithm. The analysis of obtained results showed that the size of the analysed objects on the digital images plays an important role in reliability and accuracy of the measurement. The author concludes that, in order to avoid a bias in measurement caused by insufficient object resolution, the minimal acceptable size of objects on digital images in pixels should be recommended.

Abstract

The main aim of presented article is to present methodology how sophisticated products as compressor equipment can be considered and analysed as a complex technical system which consists of jointly operating components – a set of hardware, software, operational staff and documented information. In process modelling, these components are interacting in different processes of inputs, outputs, mechanisms (resources) or management. Based on the regulatory requirements for each component of the system, a key efficiency indicator can be identified. This allows to control the process and make appropriate decisions to improve the system. The application of the proposed methodology for the development and implementation of an integrated management system reduce the cost of resources and significantly improve the quality of the implementation of processes.

Abstract

The European Union regularly develops research, development, innovation (RDI) strategies for seven years for member countries. Romania benefited from the first RDI strategy during the period 2000-2007, during which our country was trying to meet the conditions of EU accession. Romania is a member of the EU since 1st January 2007 and started, based on the EU’s RDI strategy, to develop its own strategy. The present paper aims to analyze the achievement of the general and specific objectives established by National Strategy for Research, Development and Innovation (NSRDI) 2007-2013, the evolution of the results 2014-2017 and what could be the measures and programs taken by Romania in 2019-2020 to bring our country closer to achieving the established objectives through NSRDI for the period 2014-2020.

Abstract

Underestimating the duration of the production process is one of the basic factors determining the occurrence of delays in the duration of individual operations included in the production process. Occurrence of underestimation of production time brings many negative effects, which include, among others: underestimation of the company’s production capacity, accumulation of intermediate stocks, impeded planning of the production process (scheduling of the production process) and increase of production costs. The problem of erroneous estimation of the duration of the production process is most often found in production plants specializing in serial or mass production, implemented in a parallel or series-parallel system. The basic causes that underestimate the duration of the production process include errors in production scheduling, incorrect determination of durations of individual operations carried out as part of the analyzed production process, complexity of production operations and employment structure. The occurrence of delays in the production process can also be affected by accident events that generate underestimation and costs for the enterprise (including social and economic costs). In many cases, many algorithms are used to reduce underestimation and optimization and scheduling of the entire production process. The publication presents an analysis of the production process in which the duration of the production process is underestimated, taking into account the employment structure in the manufacturing company. The analyzes allow to determine the level of underestimation of operations of the production process depending on the form of employment (steel workers – employed under a contract of employment in the production plant, and temporary workers employed by temporary work agencies), identification of the reasons for the underestimation of individual production positions and the length of their time occurrence.

Abstract

Temperature is considered a complicated external factor of the susceptibility of stainless steels to the pitting. This paper deals with the corrosion behaviour of AISI 316Ti stainless steel in temperature range 22 - 80°C in aggressive chloride environments (3 and 5% FeCl3 solutions). The corrosion resistance of tested steel is evaluated on the base of results of exposure immersion tests and cyclic potentiodynamic tests. According to the obtained results the resistance of AISI 316Ti to the pitting is markedly affected by temperature changes in the range 22 – 80°C. Intensity of corrosion attack increases with the rise of Cl concentration. Gentle changes of temperature and Cl concentration cause significant differences in character of local damage. The appearance of pitted surfaces changes with the rise of the temperature (a density of pitting increases, a size of pits decreases). The strongest change in appearance is observed between 40 and 50ºC.

Abstract

The publication presents the results of research on the statistically significant impact of the number of layers on vibration damping properties of vibroacoustic mats. The research was carried out on the author’s research stand. The research was carried out on sandwich systems made of polyurethane foam. The impact force of the analyzed variables was determined on the basis of constructed multiple regression models, the so-called multifactor models and determination of the standardized value β. The research was carried out using the PQStat software. In the models being built, the significance level was p < 0.05.

Three statistically significant linear multivariate models for one-third frequencies were constructed:

• 0-20000 Hz – a model for the entire frequency spectrum analysed during the tests,

• 0-400 Hz – a model for frequencies generating construction vibrations that may affect the worker as general vibrations,

• 50-20000 Hz – a model for frequencies that generate construction vibrations that can cause auditory sensations (noise).

It was found: positive correlation of the number of layers in vibration damping systems with a third octave frequency of up to 400 Hz; negative correlation of the number of layers in vibration damping systems with a third octave frequency of 50 to 20000 Hz.

Abstract

This paper describes interesting operational experiments have been performed in the scope of the project where the process of melting deoxidation was used under improvised conditions of cold blast cupola furnace. The goal was to find out metallurgical effects of added selfreducing briquettes prepared from steel sludge into cupola furnace charge and above all to verify the grade of deoxidation of oxides of iron at keeping output quality of cast metal. Present state of research and development of technologies of iron production in the area of commercial exploitation of these technologies is not in such a position that we could realistically assess their efficiency, investment costs and economic impacts. Moreover, an unequivocal requirement on minimization of CO2 emissions, mainly by its recycling, is here more and more promoted.

Abstract

The article deals with a reduction of friction coefficient of bearing steel 100Cr6. Reduction of friction was achieved by means of a CarbonX DLC coating. The coating exhibited excellent friction and mechanical properties. This coating was applied to samples made of 100Cr6 bearing steel. The friction results of the CarbonX coating were compared to the friction results of the 100Cr6 bearing steel. Reducing the friction of 100Cr6 bearing steel resulted in reduced wear and increase lifetime. The friction process of the samples will take place in an environment without lubrication. The aim of the article is to verify the behaviour of the DLC coating without the presence of lubricant in the friction node. The achieved results are to be interpreted in the conclusion of article.

Abstract

The chapter deals with results of cooperation within the project Electromobility in Czech-Polish Cross border Area. The electromobility is presented in comprehensive environmental and social background. The introduction is aimed at transport emission of exhaust gases resulting in global warming and harmful impact on the environment quality. The environment analysis is reflected in view of transport and passenger cars production. The chapter presents results of society analysis defining its attitude to electromobility in the region. The methodology of public questioning was chosen to reveal possibilities for electromobility development in Czech-Polish cross border area. The questions of the survey were formulated to record a public attitude and view of electromobility. The respondents’ answers reflect their awareness of this new sustainable transport.

Abstract

The paper is focused on identifying the main requirements for developing a CPPS demonstrator prototype. This research aims to categorize the main components and interactions within a new manufacturing system which are required to accommodate a CPPS. The proposed CPPS demonstrator also includes the preliminary requirements identified from the discussions with the regional industry, so that the prototype of the production system could be easily understood and also be the basis for further collaborations. The identified requirements were structured according to the top-down principle focusing on accomplishing the major objectives to be achieved through the prototype of the production system but also on the detailed concepts of the product and the production stations, thus preparing the choice for a concrete technical solution.