The near-surface ice thermal structure of the Waldemarbreen, a 2.5-square km glacier located at 78°N 12°E in Spitsbergen, Svalbard , is described here. Traditional glaciological mass balance measurements by stake readings and snow surveying have been conducted annually since 1996. The near-surface ice temperature was investigated with automatic borehole thermistors in the ablation and accumulation areas in 2007-2008. The mean annual surface ice temperatures (September-June) of the ablation area were determined to be -4.7°C at 1 m depth and -2.5°C at 9 m . For the accumulation area, they were -3.0°C at 2 m , and -2.3°C at 10 m depth between September and August. On the Waldemarbreen, at 10 m depth, the mean annual near-surface ice temperature was 4.0°C above the mean annual air temperature in the accumulation area. The Waldemarbreen may thus be classified as a polythermal type with cold ice which is below the pressure melting point and a temperate ice layer in the bottom sections of the glacier and with a temperate surface layer only during summer seasons. At a depth of 10 m , temperatures are of the order of -2°C to -3°C.

In this work, steady flow-field and heat transfer through a copper-water nanofluid around a rotating circular cylinder with a constant nondimensional rotation rate α varying from 0 to 5 was investigated for Reynolds numbers of 5–40. Furthermore, the range of nanoparticle volume fractions considered is 0–5%. The effect of volume fraction of nanoparticles on the fluid flow and heat transfer characteristics are carried out by using a finite-volume method based commercial computational fluid dynamics solver. The variation of the local and the average Nusselt numbers with Reynolds number, volume fractions, and rotation rate are presented for the range of conditions. The average Nusselt number is found to decrease with increasing value of the rotation rate for the fixed value of the Reynolds number and volume fraction of nanoparticles. In addition, rotation can be used as a drag reduction technique.

Gas-liquid two-phase flow in minichannels has been the subject of increased research interest in the past few years. Evaluation, however, of today's state of the art regarding hydrodynamics of flow in minichannels shows significant differences between existing test results. In the literature there is no clear information regarding: defining the boundary between minichannels and conventional channels, labelling of flow patterns. The review of literature on the hydrodynamics of gas-liquid flow in minichannels shows that, despite the fact that many research works have been published, the problem of determining the effect of diameter of the minichannel on the hydrodynamics of the flow is still at an early stage. Therefore, the paper presents the results of research concerning determination of flow regime map for the vertical upward flow in minichannels. The research is based on a comprehensive analysis of the literature data and on the research that has been carried out. Such approach to the mentioned above problems concerning key issues of the two-phase flow in minichannels allowed to determine ranges of occurrence of flow structures with a relatively high accuracy.

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.

This article analyses the judgment of the Supreme Court of Poland of 25 June 2020, in which the Court refused to recognise registered mail receipt forms issued by the authorities of the so-called Turkish Republic of Northern Cyprus (TRNC) as foreign official documents, despite the Public Prosecutor General and the claimant arguing to the contrary. The text attempts to show that the ruling is consistent with earlier Polish practice and the majority view in domestic literature. Still, the international jurisprudence shows that there is no clear rule of public international law that would make non-recognition of documents absolutely mandatory in such cases, and some exceptions could even support their recognition under special circumstances. Also, in similar cases foreign national courts do not always refuse recognition.

The economical combustion of gas fuel implies that it takes place with a minimum coefficient of excess air and minimal losses. Constructive, aerodynamic and physical factors have a determining influence on the completeness of combustion and the conditions of ignition. Using the ANSYS software program, the main characteristics of the combustion process in the cylindrical mixing section of a flat flame injection burner are investigated through computer simulation. A geometric model was created on which it is possible to study both straight and rotating jets. The possibility of numerically investigating the combustion of gaseous fuel (C ₃H ₈) in a confined air flow produced by injection is considered. A k-ε model of turbulence was used, which is based on the equation for turbulent kinetic energy and its dissipation rate. The purpose of the work is to study and analyze the changes and distribution of temperature and speed as well as the concentration of nitrogen oxides and carbon monoxide along the axis of the combustion chamber. The results are presented for the angles of inclination of the nozzles of 45° and 0°. Based on these, an analysis was made, where it was found that with the increase in the degree of rotation, the absolute values of the temperature increase and the change in the mass concentration of the fuel along the length of the mixing section can be used to regulate the combustion process. The created numerical model can be successfully used to determine the main parameters of the burner under the same initial conditions, changing the angle of inclination of the nozzles. The obtained results can be considered as a basis for further research related to increasing the efficiency of the combustion process and lowering the harmful emissions produced by it.

In this work, steady flow-field and heat transfer through a copper-water nanofluid around a rotating circular cylinder, dissipating uniform heat flux, with a constant non-dimensional rotation rate varying from 0 to 5 was investigated numerically using a finite-volume method for Reynolds numbers from the range 10–40. Furthermore, the range of nanoparticle volume fractions considered is 0–5%. The variation of the local and the average Nusselt numbers with Reynolds number, volume fractions, and rotation rate are presented for the range of conditions. The average Nusselt number is found to increase with increasing the nanoparticle volume fractions and decrease with increasing value of the rotation rate.

The paper describes the most important factors controlling the process of methanogenesis in the biomethanization technology. It discusses the operational regimes of temperature as well as pH, C/N ratio, the necessity for micronutrients and sensitivity to a number of toxic compounds. Components with an inhibitory effect are characterized as biostatic compounds (ammonia, VFAs, hydrogen sulfide and salinity-inducing substances) and biocidal substances (such as surfactants and pharmaceuticals). The threshold limits of the compounds in question securing the system against disturbances are introduced, as well as the measures counteracting inhibition. Some ways of overcoming the negative impact of environmental factors on the system are presented, including co-fermentation, supplementation of nutrients, removal of ammonia and hydrogen sulfide by different methods and acclimatization of methanogens to inhibitory substances.

The research was set up in the Neretva River valley in the Southern part of Croatian Karst area, where implementation of modern hydrotechnical practices within the river catchment’s area led to intrusion of seawater to groundwater resulting in soil salinization in the delta. The region has great agro-ecological potential for intensive production of vegetables and Mediterranean fruits. Since the combination of the effects of saline groundwater and the use of this water for irrigation may have disastrous effects on the productivity of agricultural soils water, a project was started in order to set up a permanent monitoring network. The aim of this study was to determine the salt dynamics in the surface water on five locations which are considered as potential sources of the irrigation water (Modric canal, Neretva River near Opuzen, Crepina, Jasenska and Vidrice pumping station) during a 4-year period (1999–2002). The surface water samples had been collected on monthly basis and analyzed for all parameters required in the irrigation water quality classification. The results show considerable spatial and temporal variability of determined parameters. Thus, in the Neretva River near Opuzen, total salt concentrations in water ranged from 0.4 to 7.7 dS·m–1, and in Modric from 1.65 up to17.2 dS·m–1. Dominant cations and anions on all observed locations were Na+ and Cl–. Constantly high concentration of Na+ in sampled surface waters is of a special concern. Utilization of the water of such quality may cause problems related to the use of alkaline waters for irrigation, which can further cause permanent loss of fertile soil.

The Parliament of the Republic of Poland was one of five European parliaments which – in view of the full-scale aggression by Russia against Ukraine which commenced on 24 February 2022 – adopted resolutions declaring the Russian Federation as a state associated with terrorism. The Polish acts are consistent with resolutions adopted on the same subject by the Parliamentary Assembly of the Council of Europe (PACE) and the European Parliament of the European Union (EP).
Although not legally binding, the adoption of these resolutions have a large symbolic dimension and may have a negative impact on the perception of and possibilities of Russian participation in the international arena. From the Polish perspective, the national decisions linking Russia with terrorist activities will influence decisions taken within the sanctions regime, as well as with regard to the legal qualification of certain acts under Polish criminal law in the course of proceedings conducted by Polish prosecution authorities in relation to the war. Finally, as long as the war continues and the assessment of Russia as a terrorist state remains in place, it will not be possible to restore and maintain ordinary diplomatic, economic and other relations with that state.

We study the autocovariance structure of a general Markov switching second-order stationary VARMA model.Then we give stable finite order VARMA(p*, q*) representations for those M-state Markov switching VARMA(p, q) processes where the observables are uncorrelated with the regime variables. This allows us to obtain sharper bounds for p* and q* with respect to the ones existing in literature. Our results provide new insights into stochastic properties and facilitate statistical inference about the orders of MS-VARMA models and the underlying number of hidden states.

The aim of the present study was to investigate the sensitivity of a multiphase Eulerian CFD model with respect to relations defining drag forces between phases. The mean relative error as well as standard deviation of experimental and computed values of pressure gradient and average liquid holdup were used as validation criteria of the model. Comparative basis for simulations was our own data-base obtained in experiments carried out in a TBR operating at a co-current downward gas and liquid flow. Estimated errors showed that the classical equations of Attou et al. (1999) defining the friction factors Fjk approximate experimental values of hydrodynamic parameters with the best agreement. Taking this into account one can recommend to apply chosen equations in the momentum balances of TBR.

In father’s footsteps or a problematic filiation. Dominique Jamet’s case – There is a phenomenon to be observed in contemporary French literature, namely the renewal of the novel through writing about self and the day-to-day reality in the context of family history. Writers reach into the past, often traumatic and painful, in order to rebuild their own broken identity, scarred by the memory of their parents’ troubled past. This is the case with Dominique Jamet. He returns to history with a capital H (the interwar period, World War Two, the Vichy regime and the subsequent issues of accounting for collaboration), so as to draw the figure of his father, Claude, an “intellectual” turncoat. The questionable filiation is the point of departure for writing two autobiographical texts. Also, it had undoubtedly been an inspiration for Un traître, a novel published in 2008, which is a fictitious reconstruction of the biography of Jacques Vasseur, an infamous French collaborator.

The relevance of the subject of research is determined by the need to develop and subsequently implement a mathematical model and the corresponding structural scheme of the convective heating surfaces of the TP-92 steam boiler. The purpose of this research work is to directly model the heat- -transfer system of the convective heating surfaces of this boiler, designed for effective use in real conditions. The basis of the methodological approach in the research work is a combination of methods of the system analysis of the key principles of constructing mathematical models of heat-transfer systems of modern steam boilers with an experimental study of the prospects for creating a mathematical model of a heat-transfer system of the convective heating surfaces of a TP-92 steam boiler. In the course of the study, the results were obtained and presented in the form of a mathematical model of a convective heat-transfer system. It allows for making effective mathematical calculations of the main operating modes of the TP-92 steam boiler and calculating the dependences of the temperature and thermal modes of its operation on the change of incoming parameters of the used heat carriers, changes in the heating surface area and the relative flow rate of the heat carriers over the time of their use. The results obtained in the study, including the conclusions formulated on their basis, are of significant practical importance for the designers of steam boilers. The results also are useful for maintenance personnel, whose immediate responsibilities include determining the real possibilities of improving the convective heat-transfer system, based on the known parameters of the temperature of the coolant at the entrance to the system and at the exit from it.

The Western boundary of Poland was established by the Potsdam Agreement of 1945 and confirmed by the Boundary Agreement between Poland and the GDR of Gőrlitz of 1950. Poland exercised administration with respect to the adjudicated territories, but she made efforts to get the boundary recognized and confirmed by the FRG. This happened on the basis of the Warsaw Treaty of 1970. Boundary treaties are usually considered as objective regimes. It is disputable whether the Warsaw Treaty of 1970 can be classified as such a regime.

In contrast to the apparently stringent EU legal regime, the deportation of EU nationals is a law enforcement device widely normalised in many European countries. Concerning deportation prac-tices, the allegedly critical divide between EU citizens and third-country nationals does not seem to make much sense in practice for some – Eastern European – national groups. Initially, this paper explores the scope and scale of this increasingly salient component of the EU deportation system, by drawing on data supplied by national databases. Additionally, it examines why and how the depor-tation of EU nationals has gained traction across the European borderscape, a phenomenon that has much to do with rampant xeno-racist attitudes, widespread concerns over so-called ‘criminal aliens’ and, last but not at all least, the street-level management of poor populations and low-profile public order issues. Finally, this paper scrutinises the strength of institutional inertias in the management of enduringly subordinated – and racialised – Eastern European populations.

Heat transfer study from the heated square cylinder at a different orientation angle to the stream of nanofluids has been investigated numerically. CuO-based nanofluids were used to elucidate the significant effect of parameters: Reynolds number (1–40), nanoparticle volume fraction (0.00–0.05), the diameter of the NPs (30–100 mn) and the orientation of square cylinder (0–90°). The numerical results were expressed in terms of isotherm contours and average Nusselt number to explain the effect of relevant parameters. Over the range of conditions, the separation of the boundary layers of nanofluids increased with the size of the NPs as compared to pure water. NPs volume fraction and its size had a significant effect on heat transfer rate. The square cylinder of orientation angle (45°) gained a more efficient heat transfer cylinder than other orientation angles. Finally, the correlations were developed for the average Nusselt number in terms of the relevant parameters for 45° orientation of the cylinder for new applications.

One of the rational ways of energy saving is to use the heat of wastewater from energy companies for open ground heating and cultivation crops. The most significant sources of heat are thermal and nuclear power plants that produce low-thermal waters of 28–35°C.
Heating of the ground with the use of circulating warm water allows to increase temperature at all points of the soil profile. The maximum thermal effect from heating ground is observed at the depth of pipe heaters (7.3– 11.1°C).
Ground heating allows to extend the growing season for crops by 3–4 weeks, which can expedite harvesting and thus maximise the harvest. In natural moisture conditions, ground heating does not lead to significant reduction of moisture reserves in the active layer throughout the growing period. There is a redistribution of moisture in a soil profile. It decreases in the zone of pipe heaters and redistributes toward the top. The formation of the nutrient regime changes, the content of mobile phosphorus and potassium, and nitrate nitrogen increases, whereas the content of ammonia nitrogen is reduced. Ground heating is a new special heat reclamation technique. It allows not only to control temperature of the agricultural crop environment, but also to dissipate heat in the ground, and promote the utilisation of waste heat and the stabilisation of the environment.

Synthetic modelling of the flood regime is based on the overall knowledge of the hydrological regime in a catchment. The Flow-duration-Frequency (QdF) modelling is used to combine three parameters characterising flood with its mean or exceeded flow, its characteristic duration, and occurrence frequency. Which of these can be established locally at the extreme mean volume flow rates of a catchment reference hydrometric station? The determination of the reference QdF model in mean (volume) and exceeded flows requires two characteristics reflecting the flood regime in a catchment. The first is the characteristic flood duration and the second is the 10-year quantile of the annual maximum instantaneous flow. The comparison of the local situation to the reference QdF models enables to develop the final QdF model of the catchment and therefore the baseline QdF for exceeded and synthetic mono-frequency hydrographs. These are essential components in the study of flood risk mapping and the estimation of the instantaneous peak distribution from mean daily streamflow series.

Liquid-gas flows in pipelines appear in many industrial processes, e.g. in the nuclear, mining, and oil industry. The gamma-absorption technique is one of the methods that can be successfully applied to study such flows. This paper presents the use of the gamma-absorption method to determine the water-air flow parameters in a horizontal pipeline. Three flow types were studied in this work: plug, transitional plug-bubble, and bubble one. In the research, a radiometric set consisting of two Am-241 sources and two NaI(TI) scintillation detectors have been applied. Based on the analysis of the signals from both scintillation detectors, the gas phase velocity was calculated using the cross-correlation method (CCM). The signal from one detector was used to determine the void fraction and to recognise the flow regime. In the latter case, a Multi-Layer Perceptron-type artificial neural network (ANN) was applied. To reduce the number of signal features, the principal component analysis (PCA) was used. The expanded uncertainties of gas velocity and void fraction obtained for the flow types studied in this paper did not exceed 4.3% and 7.4% respectively. All three types of analyzed flows were recognised with 100% accuracy. Results of the experiments confirm the usefulness of the gamma-ray absorption method in combination with radiometric signal analysis by CCM and ANN with PCA for comprehensive analysis of liquid-gas flow in the pipeline.

The research analyzed seasonal changes of the oxygen regime and related indicators on the example of water objects of the Ukrainian Polesie Region. The region shows different directions of economic use. Zebrafish ( Danio rerio Hamilton–Buchanan) and the Prussian carp ( Carassius auratus gibelio Bloch) were used as test objects to investigate survival responses. Dissolved oxygen (DO) concentration in water, pH values and temperatures were determined by standard methods. Based on research results, the main problems were determined pertaining to the oxygen regime of investigated waters, i.e. the increase in temperature and toxicity of the aquatic environment in the summer. A rather dangerous decrease in DO concentration, almost up to the levels of maximum allowable concentration (MAC) (4.10 mg∙dm–3 in group E1 and 6.07 mg∙dm–3 in group E2), was observed in August and it was typical for the reservoirs with a slow water movement. Flowing river waters (group E3) were eliminated due to their better aeration compared to other groups. The correlation analysis based on the presented data revealed a high and average degree of probable correlation between the DO concentration and water temperature, as well as an average degree of correlation with general toxicity determined on sensitive species of D. rerio, and in group E1 on the persistent species C. auratus gibelio as well. The interrelations and equations of the rectilinear regression can be used to predict the oxygen regime of the waters investigated and other surface waters having similar problems.

In the article, the author analyzes the phenomenon of adapting Bogdan Suchodolski's pedagogy to changing political circumstances several times: from his fascination with mainstream politics in the 1930s, through intensive practice of Marxist and socialist pedagogy after World War II, to universal humanism and tragic humanism in the 1970s and 80s. Following R. Englert, the author calls this adaptability of pedagogy to political changes “pedagogical cairology”.

In this paper, the recent ice regime variations in the Kara Sea have been described and quantified based on the high-resolution remote sensing database from 2003 to 2017. In general, the Kara Sea is fully covered with thicker sea ice in winter, but sea ice cover is continuously declining during the summer. The year 2003 was the year with the most severe ice conditions, while 2012 and 2016 were the least severe. The extensive sea ice begins to break up before May and becomes completely frozen at the end of December again. The duration of ice melting is approximately twice than that of the freezing. Since 2007, the minimum ice coverage has always been below 5%, resulting in wide open-waters in summer. Furthermore, the relevant local driving factors of external atmospheric forcing on ice conditions have been quantitatively calculated and analyzed. Winter accumulated surface air temperature has been playing a primary role on the ice concentration and thickness condition in winter and determining ice coverage index in the following melt-freeze stage. Correlation coefficients between winter accumulated temperature and ice thickness anomaly index, the ice coverage anomaly index, duration of melt-freeze stage can approach -0.72, -0.83 and 0.80, respectively. In summer, meridional winds contribute closely to summer ice coverage anomaly index, with correlation coefficient exceeding 0.80 since 2007 and 0.90 since 2010.