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.

Analiza stanu zasobów i ich wykorzystania w przeszłości pozwala na poznanie czynników kształtujących jego zmiany, ułatwić może ich prognozowanie i ocenę stopnia zabezpieczenia przyszłego zapotrzebowania krajowego na surowce. Znaczenie gospodarcze współcześnie w Polsce jako źródło ołowiu i cynku mają złoża: rud Zn-Pb w obszarze śląsko-krakowskim oraz rud miedzi na monoklinie przedsudeckiej, w których ołów występuje jako metal towarzyszący. Górnictwo rud cynku i ołowiu ma na ziemiach polskich wielowiekową tradycję. Do początków XXI w. w złożach śląsko-krakowskich wydobyto około 25–27 mln ton Zn i 7,5–9 mln ton Pb. Zasoby złóż są systematycznie ewidencjonowane od 1952 r. Do lat osiemdziesiątych XX wieku notowany był ich przyrost. O d 1983 roku zaznacza się stały ich ubytek spowodowany wyczerpywaniem zasobów eksploatowanych złóż. Znaczne zmniejszenie wykazywanych zasobów nastąpiło w latach 1991–1993 r. po zmianie kryteriów bilansowości, oraz w latach 2005–2007 po wprowadzeniu do szacowania zasobów metody „okręgów” zamiast wieloboków. Zasoby przemysłowe, kwalifikowane do wydobycia, zmniejszają się systematycznie w wyniku ich eksploatacji i można przewidywać całkowite ich wyczerpanie do 2022 r. W złożach niezagospodarowanych pozostało jeszcze 3 mln cynku i 1,2 mln ton ołowiu i przewiduje się 4–5 mln ton Zn i około 1 mln ton Pb w zasobów prognostycznych. W udokumentowanych złożach rud miedzi wykazywane jest 1,3–1,7 mln t Pb oraz mln to zasobów szacunkowych. Zasoby złóż niezagospodarowanych wymagają lepszego niż dotychczas rozpoznania, a w przypadku zasobów perspektywicznych ich potwierdzenia. Koniec eksploatacji złóż zagospodarowanych powinien być podstawą dla sprecyzowania polityki państwa odnośnie do przyszłości pokrycia zapotrzebowania krajowego na surowce cynku i ołowiu oraz przyszłości wykorzystania krajowej bazy surowcowej.

In recent years, the outsourcing of a variety of different activities has been more commonly observed in the coal mining industry. This is connected with employing workers by external companies. These practices are not necessarily perceived as good ones by mines’ employees because they may influence their remuneration directly or indirectly. Firstly, as external employees treat work in mining company as a source of a quick income. Therefore, external companies often calculate their employees compensation not based on working time (i.e. hours) but on the basis of a specific, accomplished task. Such employment is called piecework, whereas the workers employed in this kind of system are called output workers/piece workers. Therefore, to receive higher wages in these companies, employees carry out their tasks faster and more efficiently. This, in turn, can affect the standards of workers employed by the mining company. In addition, outsourced workers are often retired miners, so the costs incurred by employers are significantly lower. In addition, in order to not to lose the retirement benefit, they work for a much lower rate. On the other hand, outsourced work can be done in a hurry (on a piece rate), which is not conducive to compliance with safety regulations, therefore mine employees may feel unsafe. This article aims to present how mine employees assess outsourcing underground works. In order to achieve this aim, a survey was carried out among employees of one of the coal mine companies in Silesia. Participants of the survey were randomly chosen among underground miners employed at one mine company. The survey was anonymous which obviously might have influenced respondents’ honesty in answering. The survey was carried out in several mines of the chosen company. In some of them the survey was carried out online and in the remaining ones it was filled out on paper. Analyzing the survey results allowed for a better understanding of the reasons of the disapproval of outsourcing underground works. This, in turn, may be used for better human resources management including, in particular, planning an incentive based pay system.

Coal reserves in the Czech Republic are estimated to be 10 billion tons – hard coal about 37%, brown coal about 60% and lignite 3%. Hard coal is produced in Northern Moravia. In 2017 the production of hard coal was 5.5 million tons. Brown coal is mined in North-Western Bohemia − the production of brown coal in 2017 was 38.1 million tons. Significant quantities of hard coal are exported to: Slovakia, Austria, Germany and Hungary. In accordance with the National Energy Policy, coal will remain the main source of energy in the country in the future, despite the increased use of nuclear energy and natural gas. The government expects that in 2030 energy from coal will account for 30.5% of energy produced. There are five coal companies in the Czech Republic: OKD, a.s., the only hard coal producer and four brown coal mining companies: Severočeské Doly a.s., owned by ČEZ, the largest producer of brown coal, Vršanská uhelná a.s., with coal resources until 2055, Severní energetická a.s. with the largest brown coal reserves in the Czech Republic and Sokolovska uhelná a.s., the smallest mining company extracting lignite. OKD operates coal in two mines Kopalnia Důlní závod 1 – (consists of three mines: ČSA Mine, Lazy Mine, Darkov Mine) and Mine Důlní závod 2 (ttwo mines Sever, Jih). The article also presents a pro-ecological solution for the management of waste heaps after coal enrichment – a plant for the enrichment of coal waste from the Hermanice heap.

The article is devoted to more comprehensive use of medieval onymic resources in research on the history of the Polish language. These materials were used in research on the phonetic development of the Polish language in its earliest period. To date, they have rarely appeared in lexical studies. The body of the oldest appellatives, reconstructed on the basis of proper names, would be a kind of lexicon (supplement) enriching and verifying old Polish lexical material, certifi ed in historical Polish dictionaries (also in etymological dictionaries). In this way, the expectations formulated over 100 years ago by eminent Polish linguists may be fulfi lled. The complementary use of such a huge wealth of material opens up further research perspectives towards etymological, dialectological, lexical and morphological research.

Surowce energetyczne są podstawą dla wytwarzania energii w formie ciepła i prądu na Ziemi. Obecne rozwiązania dotyczące konstrukcji bezpiecznych i ekonomicznych reaktorów jądrowych, jak również proces wykorzystania energii z odnawialnych źródeł energii, ponadto przyszłościowe rozwiązania otrzymywania czystej energii z wodoru, ogniw paliwowych i innych źródeł mają decydujący wpływ na zmianę tego tradycyjnego podejścia. Niemniej jednak, kopalne surowce energetyczne (ropa naftowa, gaz ziemny i węgiel) nie mają obecnie substytutów, które sprostałyby wymaganemu zapotrzebowaniu na energię. W artykule omówiono problemy i wyzwania związane z wykorzystaniem kopalnych paliw w energetyce polskiej. Przybliżono stan zasobów (bilansowych i przemysłowych) pierwotnych nośników energii: węgla kamiennego, węgla brunatnego, ropy naftowej, gazu ziemnego i metanu pokładów węgla. Zwrócono szczególną uwagę, że bardzo duże zasoby węgla kamiennego i brunatnego mogą i powinny być wykorzystywane w gospodarce kraju. Przeszkodą dla długoterminowego wykorzystania tych nośników w energetyce jest polityka energetyczno-klimatyczna Unii Europejskiej, która zdecydowanie zmierza do znaczącej redukcji emisji gazów cieplarnianych. Dokonano również omówienia stanu obecnego krajowej energetyki konwencjonalnej, jak również zarysu jej przyszłości. Zwrócono uwagę, że zapewnienie bezpieczeństwa dostaw energii elektrycznej będzie wymagało znacznego wysiłku inwestycyjnego zarówno w sektorze wytwórczym, jak i sieciowym. Artykuł zwieńcza omówienie problemów i wyzwań związanych z funkcjonowaniem krajowego sektora energii. Należy podkreślić, że nadszedł czas na podjęcie przez rząd strategicznych decyzji, dotyczących kształtowania przyszłej struktury paliwowej systemu wytwarzania energii. Polska musi w dalszym ciągu zmierzać w kierunku gospodarki niskoemisyjnej, a rozwój zaawansowanych technologii ograniczających emisję i podniesienie efektywności energetycznej to właściwy kierunek działań.

The continental shelf beyond 200 nautical miles (NM) accounts for a great value for States. The development of technologies and science has allowed the human economic and scientific activities on the deep parts of the ocean floor. The continental shelf is rich with living resources. The living resources of continental shelf are also valuable, since they possess valuable genetic resources for pharmaceuticals and commercial products. Many valuable non-living resources are situated on the continental shelf, including hydrocarbons (oil and gas) and minerals (e.g. manganese, nickel, cobalt, gold, diamonds, copper, tin, titanium, iron, chromium and galena). Therefore, States have spent significant resources on conducting a research and exploring their continental shelf and the Commission on the Limits of the Continental Shelf (CLCS) has received seventy-seven submissions and issued twenty-nine recommendations pursuant to Article 76 (8) of the United Nations Convention on the Law of the Sea (UNCLOS). With the expected improvement of technological capabilities in decades to come, especially, in deep waters, the continental shelf will be explored more thoroughly and perhaps will meet no technological limits.

Prognozuje się, że zasoby wody słodkiej dostępne dla ludzkości zmniejszą się o 30 proc. w ciągu najbliższych 20 lat. Jak odwrócić degradację zasobów wody i zrównoważyć zapotrzebowanie ludzi na wodę z potencjałem hydrosfery?

Production rates for various activities and overall construction project duration are significantly influenced by crew formation. Crews are composed of available renewable resources. Construction companies tend to reduce the number of permanent employees, which reduces fixed costs, but at the same time limits production capacity. Therefore, construction project planning must be carried out by means of scheduling methods which allow for resource constrains. Authors create a mathematical model for optimized scheduling of linear construction projects with consideration of resources and work continuity constraints. Proposed approach enables user to select optimal crew formation under limited resource supply. This minimizes project duration and improves renewable resource utilization in construction linear projects. This paper presents mixed integer linear programming to model this problem and uses a case study to illustrate it.

The high and rapidly increasing demand for maritime space for various purposes, such as: shipping and fishing, production of energy from renewable sources, oil and gas exploitation, environmental conservation, tourism and aquaculture, as well as the multiple pressures on coastal resources, require integrated planning and management approach. In the law of the European Union, maritime governance has been developed in the Integrated Maritime Policy. The aim of this article is to show maritime spatial planning as a tool that enables public authorities to apply an integrated and trans-boundary approach.

The main aim of the maritime spatial planning is to promote sustainable development and growth in the maritime sector, applying an ecosystem-based approach, and to achieve the coexistence of relevant activities and uses. In order to achieve that purpose, Member States should ensure that the planning process results in a comprehensive planning taking into consideration inter alia long-term changes due to climate change.

The assurance of future raw materials supply to the EU mineral industry has become, in recent years, one of the priority tasks of the EU Commission, geological surveys and several research centers. After many years of negligence, the problem of developing supply risk of many raw materials in Europe has been perceived, along with the menace to the EU economy competitiveness coming from dynamically developing countries such as China, India and others - basically of Asian origin. This has initiated a new mineral policy within the EU zone, referring mainly to non-fuels. One of the starting points for this activity has become the assessment of the EU mineral resources potential and identification of the raw materials that are critical for the harmonious and sustainable development and technological progress. The paper briefly presents the results of research work focused on the critical raw materials assessment, which were conducted by the Initiative for the Raw Materials Supply. Its core is the presentation of Polish mineral reserve base and its potential as a possible source of critical raw materials for the European Union. The criticality analysis was based on three categories, i.e.: economic consequences of the supply limitation, supply risk of reduction (fluctuation or disruption), and environmental risk referring to countries with weak environmental performance in order to protect the environment that jeopardize the supply of raw materials to the EU. For their quantitative assessment there were proposed three aggregated indices, while for the forecast purposes - 10-year period. The criticality ratio was determined for the 41 most important and most frequently used raw materials. On the grounds of the research made up to now, these raw materials were preliminary divided into three groups. As a critical to the EU economy, 14 raw materials of major economic importance were discriminated, i.e.: antimony, beryllium, cobalt, fluorite, gallium, germanium, graphite, indium, magnesium, niobium, PGM, rare earths, tantalum, and tungsten. They are characterized by high supply risk, which is mainly due to limited number of their sources - dominated by a few countries, in particular China. The risk of supply disruptions is boosted by low rate of utilization of secondary sources, and limited scale of substitution as well. The majority of the above-mentioned raw materials are crucial for the new technologies development. The remaining minerals arealso - though to a lesser extent - imperiled with a supply deficit. Despite they are also of economic importance, their indispensability for the advanced technologies development is relatively smaller. Taking into account the raw materials that are critical for the European Union economy, Poland cannot be considered as its resource base. The source of these raw materials are not only scarce in Poland, but also they are not produced, and their demand is now - and according to forecasts is going to be in the future - met by imports. However, the role of our country as a manufacturer of finished products from components of foreign origin is anticipated to increase. The raw materials in question are not considered exactly critical for Polish economy, as any industrial branch based upon their utilization has emerged so far. Therefore, they are of limited economic importance. Presumable utilization of very limited sources of above-mentioned critical raw materials in Poland could be anticipated in a perspective of at least 20 years. The most probable in this respect are the following: opening out the new Mo-W-Cu ore deposit Myszków, and the promotion of exploration works for similar deposits.

This paper presents the issue of the vertical extension of buildings, mainly residential, as an element of sustainable housing policy of European cities. This type of construction project allows for the acquisition of additional residential space, using the existing technical infrastructure, and also not deepening the effect of urban sprawl. Vertical extensions allow for the construction of new apartments in urban areas, being one of the forms of densifying the existing buildings. The study reviews research on the subject of vertical building extensions, trying to answer the research questions posed: how and with the use of which building analysis tools it is possible to improve the process of vertical extension, so that it can become an actual element of the housing policy of cities. Three original studies were selected for the analysis: from Germany, Belgium and England, which met the criteria set by this study, presenting a universal scheme of action for vertical extensions, not treating them as incidental, individual construction intervention, and treating vertical extensions as an element of systemic action for the acquisition of new apartments. The selected studies are carried out in countries economically and culturally similar to Poland, which was also one of the selection criteria. The study is also to be a voice in the discussion on the possibility of the vertical extension of residential buildings as an element of housing policy in Poland.

Phosphate rocks and elemental phosphorus are considered to be critical raw materials mainly because of such parameters as the growing prices of phosphate fertilizers, the high concentration of producers limited to several countries in the world, the exceptional significance of phosphorus in agriculture and the inability to substitute it.
In Poland 100% of the demand phosphate rocks relies on import. The expansion and mining of the nation’s own resource base may be an alternative to import and a way to provide safety of supplies. Historically, phosphorites from the northern margin of the Holy Cross Mountains were extracted using the underground method, which was abandoned in the beginning of the 1970s due to the unprofitability of extraction. However, in eastern and south-eastern Poland, phosphorite concretions of the Eocene age occur at shallow depths, which can have local significance as mineral deposits and might be extracted in open-pit mines. The economics of mining in shallow opencasts do not require such stringent limiting parameters for phosphate deposits as those currently valid, which were established for underground mining conditions.
In this publication, the authors analyzed contemporary conditions for a cost-effective phosphorite deposit, including the price fluctuations of phosphate rock, a review of threshold parameters of deposits for phosphorite projects in the world, and the economics of open-pit ore extraction, where an aggregate mine with mixed extraction (partially from below the water table) was adopted as a point of reference.
As a result, new threshold parameters defining an ore deposit and its boundaries are proposed for Eocene phosphorites in Poland.

The economic downturn in Europe and in the world, has affected the traditional branches of industry in a particular way. Development plans of domestic coke plants in terms of main production assets for the next years have been presented. Taking into account the current market situation, the coke plants strategy should aim at risk minimization through application of already known technologies. On the other hand, investments in scope of new and innovative technologies which are connected with a high level of variability, should be seen as an opportunity. Thus, evaluation of investment projects should be done in a different way than so far. The traditional discount analysis, because of its static nature, does not take into account variability and options included in projects with many decision moments - it can prove to be not sufficient. A tool which helps the decision makers in such situations, is the real options analysis. The article presents the findings of the research-development project on coal blend pre-drying implementation, realized by Zdzieszowice Coke Plant and ICHPW in Zabrze. The results achieved so far, as well as the concerns resulting from the project, have been discussed in this article. Further project development plans, aiming at the construction of a semi industrial research installation for analysing the impact of pre-drying on the coke making process have been presented. The article describes premises for the application of real options analysis as a tool to evaluate projects, the results of which are uncertain. The origin and structure of real options as well as the conditions of their application compared to traditional, discount based project evaluation methods, have been presented. The origin and characteristic parameters of real options have been discussed. In the next part, by applying the NPV and real options method, the research-development undertaking of coal blend pre-drying implementation on two coke batteries, has been evaluated. In order to assess the real option's value of the project, which is a classic European call option, the Black-Scholes formula has been used. The achieved results have been compared as well as the flexibility rate of the analyzed research-development project has been defined.

The study addresses the challenges facing the law of the sea. Although UNCLOS is rightly described as a constitution of the law of the sea, it does not and cannot give answers to all problems and doubts that arise in practice and that are related to global warming, protection of biodiversity, legal status of genetic resources, controversy concerning shipping, delimitation of areas or the protection of underwater cultural heritage. Hence the question arises, what the ways and means of further development of the law of the sea are. Undoubtedly, one of the possibilities is to develop implementation agreements, of which the third devoted to the protection and sustainable use of marine biodiversity outside national jurisdiction is the subject of an international conference convened by the General Assembly, whose resolutions in the area of the law of the sea play an important role. Undoubtedly, also the importance of the organization of the United Nations system, such as the IMO, FAO, UNESCO, UNEP is significant. There is also the possibility of accepting agreements addressing the issues left by UNCLOS without solution or definition. Not without significance is the soft law and the practice of states as well as the position of the organs appointed by UNCLOS.