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Abstract

Food production system, due to the mass scale of its manufacturing, distribution, and consumption, is subject to rigorous protection and control. The analysis of food safety presented in the foregoing publication shows that legal and organizational regulations are not alone sufficient to ensure that the quality of products does not pose a health and environmental threat. The results of the study conducted with the participation of 15 subjects make it evident that the issue of food safety is complex and requires continual monitoring because of ever changing conditions. It is increasingly seen that food safety is a key factor in supply chains, becoming the overriding element of production systems. Production companies spend more and more money on control and modernization of the entire production-related system so that food safety is 100% guaranteed. In the last few years, it can be seen that audits in manufacturing companies that deal with the production and sale of food are largely focused on food safety, process monitoring systems and employee access controls to individual production zones. Not without significance is the fact that additional departments are created in manufacturing companies, whose main task is to control production processes in terms of food safety, both from the side of the safe use of raw materials, packaging and the interference of unauthorized persons. It is absolutely necessary to emphasize that the paper also shows some examples that can already be treated as the first symptoms of food terrorism, which is becoming a deadly tool for current and future food terrorists. The publication emphasizes that food safety in the market reality of that time may be of paramount importance in the supply chains, given the importance and consequences of possible mass contamination of food.

Abstract

In order to maintain and improve its competitive advantage, the ability of 21st-century armies to recognize, anticipate, adapt and manipulate IoT on the future battlefield is important. The explosive growth of innovation in the commercial sector which utilizes the integration of cloud computing, mobile communications, sensor data collection networks and artificial intelligence is a major challenge for the military. A new concept, still untapped, called the Battlefield Things Internet (IoBT) comes from here.

Abstract

Currently, organic halogen compounds (halogen derivatives) are often identified in water. The paper presents the problem of the presence of these newly formed compounds during water treatment processes and their occurrence in sewage. The general indicator determining the content of these compounds in aqueous solutions is the concentration of halogen derivatives of organic compounds adsorbed on activated carbon AOX, which is converted to the concentration of chlorides. The groups of derivatives of halogenated organic compounds containing chlorine and/or bromine in a molecule were characterized, and the precursors and potential for the formation of these compounds in water were described. Moreover, technological methods to prevent and remove them were described.

Abstract

On December 29, 2018, the Government Emergency Ordinance no. 114/2018 has been published. This Ordinance, among others, established a multitude of measures, both economic and fiscal that aimed companies acting in the energy field. The monetary contribution, received from the license holders in the field of energy, was set at the level of 2 %, which means an increase of 20 times of this duty. These companies also have the obligation to sell the natural gas quantities, resulting from the current domestic production activity, at the price of 68 lei / MWh to eligible suppliers and final customers. All these measures have had a direct impact on companies acting in the energy field, affecting their profitability and simultaneously their ability to carry out investment projects. This paper analyzes the way the e companies listed on Bucharest Stock Exchange, acting in energy field, were affected by Government Emergency Ordinance no. 114/2018 measures.

Abstract

Research results on the quality of work of a seed cutter for selected cultivars of sweetcorn were presented. Measurements were carried out at the rotational speed of a head of 1600 rot. min−1 and a linear velocity of the cob conveyor of 0.31 m s−1. A statistically significant relation between the degree of cutting the seed mass and the selected mechanical properties of grain were determined. Differences between cultivars at the level of approximately 43% for the force of perforation of the peri-carp Fp,

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

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.