Global brown coal resources are estimated to be extracted at around 512 million Mg. They are found in over a dozen countries, including primarily: Australia, China, the Czech Republic, Greece, Germany, Poland, Russia, the United States and Turkey. More than 80% of total brown coal production in the EU takes place in: Germany, Poland, Greece and the Czech Republic. This means that the majority of production still uses conventional fuels, including both hard coal and brown coal. Given the current energy needs in the context of brown coal reserves depletion and the impacts of the current climate and energy policies of the EU, it is very important that all new investments in mining and energy complexes based on brown coal resources must be prepared carefully to ensure high production efficiency and minimize negative environmental impacts. This article attempts to solve a problem involving the choice of the location of the opening cut to expose brown coal deposits. Due to the stratified nature of brown coal deposits and the associated open-cast mining technology used in a continuous mining system with bucket wheel excavators, belt conveyor systems and spreaders, the location of the opening cut is not completely random and the number of potential solutions is finite. The multifaceted technical, organizational, economic, social and environmental problems require a holistic approach to this research problem. Such an approach should take the different, often opposing, perspectives of the many stakeholders into account. These issues can be solved using mathematical tools designed for multiple-criteria decision support. With the proposed method, a ranking of alternatives can be created, depending on the predefined location of the opening cut.

The image analysis consists in extracting from the information which is available to the observer of the part that is important from the perspective of the investigated process. This process usually accompanies a considerable reduction in the amount of information from the image. In the field of two-phase flows, computer image analysis can be used to determine flow and geometric parameters of flow patterns. This article presents the possibilities of using this method to determine the void fraction, vapor quality, bubble velocity and the geometric dimensions of flow patterns. The use of computer image analysis methods is illustrated by the example of HFE 7100 refrigerant methoxynonafluorobutane condensation in a glass tubular minichannel. The high speed video camera was used for the study, and the films and individual frames received during the study were analyzed.

Rok 2017 w ponad 150-letniej historii węglowodorów będzie jednym z wielu podobnych. Ale dla skroplonego gazu ziemnego będzie rokiem przełomu. W Azji na liderem wzrostu importu stały się Chiny, wychodząc na drugiego światowego importera, wyprzedzając nawet Koreę Południową i mocno rywalizując z Japonią. Otwarto Kanał Panamski dla handlu LNG i „drogę północną” tak, że pojawiły się w Europie dostawy rosyjskiego gazu skroplonego. Rok 2017 stał pod znakiem dramatycznego skracania długości zawartych kontraktów long-term, krótszych ich kadencji i zmniejszania wolumenów – czyli był kolejnym okresem urynkowienia commoditization handlu tym surowcem energetycznym. Artykuł opisuje bieżący stan produkcji i handlu LNG w 2018 roku. Koncentruje się na wydobyciu gazu ziemnego w Stanach Zjednoczonych, Katarze, Australii, Rosji jako krajów mogących produkować i dostarczać LNG do Unii Europejskiej. Szczegółowo przeanalizowano kwestię cen i warunków kontraktów w 2017 r. Autorzy podkreślają, że rynek obecnie cechuje nadpodaż i utrzyma się ona co najmniej do połowy 2020 r. Novatek, Total – liderzy projektu Yamal-LNG – oddali do użytku instalację skraplającą na 5,5 mln Mg/r., a tankowiec Christophe de Margerie był pierwszą komercyjną jednostką, która pokonała trasę do Norwegii, a później dalej do Wielkiej Brytanii bez pomocy lodołamaczy i ustanowiła nowy rekord na Północnej Drodze Morskiej. W 2017 r. rosyjski koncern zwiększył udział w europejskim rynku gazu z 33,1 do 34,7%. Rosja, ale i Norwegia wyeksportowały w 2017 r. do Europy (i Turcji) rekordowe wolumeny „rurowego” – klasycznego gazu ziemnego, odpowiednio 194 i 122 mld m3, czyli o 15 i 9 mld m3 gazu ziemnego więcej niż w 2016 roku. Jeszcze w 2016 r. stawiano tezę, że Rosja łatwo nie odda swojej strefy wpływów i będzie robić wszystko oraz wykorzystywać najróżniejsze mechanizmy, nie tylko rynkowe, by inny niż rosyjski gaz ziemny był po prostu droższy i ekonomicznie mniej opłacalny. Podkreślano również, że presja, jaką wywiera na Rosjanach cały czas technicznie możliwe i ekonomicznie opłacalne przekierowanie do europejskich terminali metanowców wyładowanych amerykańskim LNG powoduje, że Gazprom nie ma wyboru i musi dopasowywać swoje ceny. Amerykanie, ale i każdy inny dostawca (Australia?) po prostu mogą to zrobić i sama ta świadomość po prostu wystarcza, by rosyjski gaz musiał być obecny w Europie w dobrej cenie.

Housing resources as an element of material infrastructure determine socio-economic development on a local, regional and national scale. Their economic and physical accessibility affects the development of human, social and relational capital, determines the competitiveness of the territory and can be seen as a generator of income both in the individual sense and in relation to the whole society. The article has a theoretical character and its aim is to identify the relationship between satisfying the housing needs of local communities and the development of territorial capital. The article also analyzes factors that allow the qualification of housing resources as a strategic resource for the development of a territory.

This paper presents a study of the effect of the modification and cooling rate on the grain count α(Al) in the Al-5Cu alloy. Research was

performed on castings with walls thickness between 3 mm and 25 mm. Cooling curves were recorded to determine the cooling rate and the

degree of undercooling at the beginning of solidification. It has been shown that cooling rate increases exponentially as the wall thickness

of casting decreases. Moreover it has been demonstrated that the cooling rate of castings changes within a wide range (21ºC/s - 1ºC/s)

when the wall thickness changes from 3 up to 25 mm. Metallographic examinations revealed primary grains (primary α(Al) grains). The

paper show that the relationship between the grain count and the degree of undercooling (for non-modified and modified alloys) can be

represented by the equation N = Nv = np·exp(-b/ΔTα), based on the Weibull's distribution of the size of nucleation sites.

The article describes how to identify the boundary and yield surface for hypoplastic constitutive equations proposed by Wu, Gudehus and Bauer. It is shown how to identify and plot the surfaces for any equation in this class. Calculation errors are analyzed characteristic for applied set of numerical formulas. In the paper there are computer links to the source code prepared in the MATLAB system, based on instructions in the article. A sample consitutive domains are shown, plotted using the attached computer program.

Investigations of refrigerant condensation in pipe minichannels are very challenging and complicated issue. Due to the multitude of influences very important is mathematical and computer modeling. Its allows for performing calculations for many different refrigerants under different flow conditions. A large number of experimental results published in the literature allows for experimental verification of correctness of the models. In this work is presented a mathematical model for calculation of flow resistance during condensation of refrigerants in the pipe minichannel. The model was developed in environment based on conservation equations. The results of calculations were verified by authors own experimental investigations results.

Attempts to perform synthesis of a passive vibroinsulation two-mass system intended for the simultaneous reduction of machine frame vibrations and forces transmitted to foundations by supporting elements were undertaken in the study. In view of the variable frequency of the machine operation, it was necessary for the frequency interval, encompassed by the vibroinsulation system operation, to be within given limits. On the grounds of properties of the linear massive-elastic system formulated in the works of Genkin and Ryaboy (1998), the problem of vibroinsulation system synthesis was formulated in the parametric type optimisation approach with equality and inequality limitations. For piston compressor vibroinsulation, the mass and elasticity matrices of the vibroinsulating system, as well as its physical structure, were determined. Its operation was verified on the basis of simulation investigations, taking into account the system loss and transient states.

The article is dedicated to the determination of the types and functions of “someone else’s word”, i.e. intertextual relationships, present in political dramas of contemporary Russian writers. The author focuses on two types of intertexts such as quotes and allusions; determines their importance to the dramatic work as a whole, and distinguishes topic-related groups of texts to which dramatists refer. The conclusions of the study incline to place the phenomenon of political drama between what is “literary” and “social”, “eternal” and “up-to-date”.The analysis was carried out on the materials of dramas such as: Putin.doc by Victor Teterin, Sentry (Часовой) by Siergiej Reshetnikov, Meat by Olga Pogodina, and Beria by Dmitry Karapuzov.