There is no way that having the United Kingdom, such an important element in the Old Continent’s system of science, leave the EU will fail to have serious consequences affecting the other EU states.

The Bulletin of the Polish Academy of Sciences: Technical Sciences (Bull.Pol. Ac.: Tech.) is published bimonthly by the Division IV Engineering Sciences of the Polish Academy of Sciences, since the beginning of the existence of the PAS in 1952. The journal is peer‐reviewed and is published both in printed and electronic form. It is established for the publication of original high quality papers from multidisciplinary Engineering sciences with the following topics preferred: Artificial and Computational Intelligence, Biomedical Engineering and Biotechnology, Civil Engineering, Control, Informatics and Robotics, Electronics, Telecommunication and Optoelectronics, Mechanical and Aeronautical Engineering, Thermodynamics, Material Science and Nanotechnology, Power Systems and Power Electronics.

Journal Metrics: JCR Impact Factor 2018: 1.361, 5 Year Impact Factor: 1.323, SCImago Journal Rank (SJR) 2017: 0.319, Source Normalized Impact per Paper (SNIP) 2017: 1.005, CiteScore 2017: 1.27, The Polish Ministry of Science and Higher Education 2017: 25 points.

Abbreviations/Acronym: Journal citation: Bull. Pol. Ac.: Tech., ISO: Bull. Pol. Acad. Sci.-Tech. Sci., JCR Abbrev: B POL ACAD SCI-TECH Acronym in the Editorial System: BPASTS.

The paper presents the result of an evaluation of the performance of different message broker system configurations, which lead to the construction of the specific architecture guidelines for such systems. The examples are provided for an exemplary middleware messaging server software - RabbitMQ, set in high availability - enabling and redundant configurations. Rabbit MQ is a message queuing system realizing the middleware for distributed systems that implements the Advanced Message Queuing Protocol. The scalability and high availability design issues are discussed and the possible cluster topologies and their impact is presented. Since HA and performance scalability requirements are in conflict, scenarios for using clustered RabbitMQ nodes and mirrored queues are interesting and have to be considered with specific workloads and requirements in mind. The results of performance measurements for some topologies are also reported in this article.

This paper discusses contemporary transformations in the way work is organised and the consequences for the stability of careers and biographies. It debates the widely held belief that organised and predictable life-course paths (including professional careers) have ceased to exist and that work itself has lost its stabilising quality. Biographical data collected among Polish employees of transnational corporations within the project “Poles in the World of Late Capitalism” proves that even though transnational corporations are widely criticised for propelling neoliberal tendencies in the global economy, they provide a means of protecting their employees against today’s uncertainty and occupational risk. Three empirical cases are presented to show how work in a transnational corporation may contribute to achieving and maintaining stability for persons who have had troublesome experiences of working in other sectors of the labour market.

Among the elements that compose steel slags and blast furnace slags, metallic precipitates occur alongside the dominant glass and crystalline phases. Their main component is metallic iron, the content of which varies from about 90% to 99% in steel slags, while in blast furnace slags the presence of precipitates was identified with the proportion of metallic iron amounting to 100%. During observations using scanning electron microscopy and X-ray spectral microanalysis it has been found that the form of occurrence of metallic precipitates is varied. There were fine drops of metal among them, surrounded by glass, larger, single precipitates in a regular, spherical shape, and metallic aggregates filling the open spaces between the crystalline phases. Tests carried out for: slags resulting from the open-hearth process, slags that are a by-product of smelting in electric arc furnaces, blast furnace slags and waste resulting from the production of ductile cast iron showed that depending on the type of slag, the proportion and form of metallic precipitates is variable and the amount of Fe in the precipitates is also varied. Research shows that in terms of quality, steel and blast furnace slag can be a potential source of iron recovery. However, further quantitative analyses are required regarding the percentage of precipitates in the composition of slags in order to determine the viability of iron recovery. This paper is the first part of a series of publications aimed at understanding the functional properties of steel and blast furnace slags in the aspect of their destructive impact on the components of devices involved in the process of their processing, which is a significant operational problem.

The mines play an important role in the economic growth of countries since they are suppliers to many industries. In addition to the economic growth, the mines positively affect the social development factors such as the employment creation, the development of rural areas, building new roads, and etc. But sometimes it may lead to the negative environmental, and social impacts. Therefore, the mining activities should be carefully monitored for the concept of sustainable development. In this paper, a fuzzy Best-Worst Method based approach is developed for the evaluation of an iron mine. The case study, Sangan iron ore mine is one of the biggest mines, located in a rural area in the north eastern of Iran. Three factors including the economic, environmental, and social parameters were considered as main sustainable development criteria. The sub-criteria for each mentioned factor were then extracted from the literature as well as knowledge expert’s opinions. In the proposed approach, each sub-criterion was carefully weighted using the fuzzy Best-Worst method and scored by 12 experts. Afterwards, the sustainability score was defined as the summation of final fuzzy scores which was gone under a defuzzification process. The performance evaluation was calculated using this sustainability score resulted to a score of 0.626 out of 1, indicating its acceptable performance. The results showed that the mine performs well in terms of the economic benefits, rate of return, exploration capacity, and stockholders’ rights, but in the environmental management systems, water discharge, recreation and tourism aspects, it does not play well. The results of the implementation of the proposed approach showed the efficiency and effectiveness of the proposed approach that is confirmed by experts.

The semantics of temporal distributiveness comes into the fore in two cases: a) either when a habitual activity is correlated with the recurrent periods of time; b) or when the recurrent periods of time are accompanied by an activity. The present paper is yet another contribution to a series of papers exploring Polish temporal constructions with distributive meaning. It focuses on constructions with the pronoun każdy, such as (spotykamy się) w każdą sobotę (każdą sobotę).

The aim of this paper is to analyse the metaphorical and metonymical conceptual representations of God in The New Testament. The notion of God causes various problems since God is understood as One in Three Persons: the Father, the Son, and the Holy Spirit. The idea of the Holy Trinity escapes human logic and natural reasoning. The metaphors and metonymies used for the conceiving of God in The New Testament form a complex system of schemata, mediating between the indescribable reality and language. Because of the transcendent nature of God, classifying some of the schemata as metaphor or metonymy is problematic.

The issue of the educational system remains one of the crucial areas for the discussions pertaining to migrants’ integration and contemporary multicultural societies. Ever since the inception of compulsory schooling, children and youth have partaken in largely state-governed socialisation in schools, which provide not only knowledge and qualifications, but are also responsible for transferring the culture and values of a given society. Under this premise, the schooling system largely determines opportunities available to migrant children. This paper seeks to address the questions about the pathways to youth Polish migrant integration, belonging and achievement (or a lack thereof) visible in the context of the Norwegian school system. The paper draws on 30 interviews conducted in 2014 with Polish parents raising children abroad, and concentrates on the features of Norwegian school as seen through the eyes of Polish parents. Our findings show that the educational contexts of both sending and receiving socie-ties are of paramount importance for the understanding of family and parenting practices related to children’s schooling. In addition, we showcase the significance of Norwegian schools for children’s integration, illuminate the tensions in parental narratives and put the debates in the context of a more detailed analysis of the relations between school and home environments of migrant children. The paper relies on parental narratives in an attempt to trace and reflect the broader meanings of children’s education among Poles living abroad.

The Return Directive allows for the detention of minors during removal proceedings, but only as a ‘last resort’, for ‘the shortest appropriate period of time’ and with the primary consideration of the ‘best interests of the child’. While the Directive attempted to provide some safeguards to minors, these are undermined throughout, as the enforcement of such provisions depends significantly on their incorpo-ration into domestic law. I provide an overview of the EU detention policy, map the existing domestic law framework in light of the benchmarks set out by the Directive and human rights instruments, and argue that there is a lack of consistency in the case study of Poland. In doing so, I analyse the limitations to detaining minors in light of the human rights treaties, of the jurisprudence of the Court of Justice of the European Union and the European Court of Human Rights, and of the role of the monitoring body – the Committee on the Rights of the Child. In discussing the different types of jurisprudence, I illustrate how different bodies speak with the same voice on the detention of minors. Based on these findings I attempt to contribute to the policy debate on how to reconcile and balance the implications of two policy objectives affecting irregular migrant children - the protection of minors and immigration en-forcement. I identify detention policy aspects, for which the legislation should be further harmonised, and I develop models of good practices based on other Member States’ practices, thus providing a set of policy recommendations to the Polish legislator as to what fair and effective irregular migration governance might entail.

While the number of forced migrants moving out of conflict-ridden or otherwise troubled regions into rela-tively stable and safe parts of the world is higher than ever, the countries of destination are increasingly trying to prevent migrants from reaching their territories. Given the scale of forced displacement and current trends of tightening immigration policies, it should be expected that tragedies at the borders, similar to that recently witnessed in Europe, will become the norm rather than the exception and that new discourses and practices will continue to emerge, transforming territorial borders in various parts of the world into highly conflictual and politicised ‘borderspaces’. This article is a contribution to the understanding of borders through a case study of the recent policy of ‘closed doors’ that Poland has adopted towards Russia’s North Caucasus asylum seekers at the country’s eastern border with Belarus, preventing them from entering the territory and claiming protection. It demonstrates that, through the process of ‘bordering’, power is no longer exercised only by the border guards at the crossing point in Terespol from where asylum seekers are being returned and that it is increasingly to be found in social practices that occur on both sides of the border, away from the clearance points. The article examines the various practices of resistance undertaken by the asylum seekers and other actors on several different levels in response to the changed reality at the border. It also analyses the meanings and discourses developed by Polish state actors in order to legitimise restrictive migration policies.

The pump performance and occurrence of cavitation directly depends on different operating conditions. To cover a wide range of operation conditions for detecting cavitation in this work, investigations on the effect of various suction valve openings on cavitation in the pump were carried out. In order to analyse various levels of cavitation in different operation conditions, the effect of the decrease in the inlet suction pressure of the centrifugal pump by controlling the inlet suction valve opening was investigated using this experimental setup. Hence, the acoustic and pressure signals under different inlet valve openings and different flow rates, namely, 103, 200, 302 l/min were collected for this purpose. A detailed analysis of the results obtained from the acoustic signal was carried out to predict cavitation in the pump under different operating conditions. Also, the acoustic signal was investigated in time domain through the use of the same statistical features. The FFT technique was used to analyse the acoustic signal in the frequency domain. In addition, in this work an attempt was made to find a relationship between the cavitation and noise characteristics using the acoustic technique for identifying cavitation within a pump.