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Two-photon double ionization of atoms in attosecond x-ray radiation fields
PublicationWe consider two-photon double ionization of helium with 100, 200, and 400 eV excess energy for the two ejected electrons, corresponding to photon energies of 89.5, 139.5, and 239.5 eV, respectively. We focus on the case of ultrashort pulses (two oscillations of the field) and develop an approach to calculate the two-photon transition matrix elements within the lowest order of the time-dependent perturbation theory. One of the...
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Experimental and Computational Fluid Dynamics Studies on Straight and U-Bend Double Tube Heat Exchangers with Active and Passive Enhancement Methods
PublicationIn this work, the authors wanted to demonstrate the possibility to increase the heat transfer efficiency by using simple wire coil inserts to create turbulent flow in the boundary layer as well as air blowing into the annulus of the pipe. Experimental investigations were carried out for four heat exchanger constructions, i.e., plain double tube, turbulized double tube, plain U-bend double tube, U-tube with turbulator, plain double...
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Rural Landscapes of Roman (northern) Liburnia: Diachronic Development of Organisation and the Economy in Extra-Urban Territories in the Light of Recent Archaeological Research
PublicationThe archaeology of Roman rural landscapes in the province of Dalmatia, and especially northern Liburnia, has until recently focused on single-site or single-monument analyses, allowing for only geographically patchy and chronologically limited conclusions. Considering the results of recent research in the wider Kvarner and sub-Velebit area, the paper discusses issues of Roman extra-urban territorial organization, the formation...
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Investigation of the vertical distribution of the sound speed of the Gulf of Gdansk in the years 2000-2010
PublicationThe conditions of the acoustic wave propagation in the southern Baltic are much more complex than in other shallow waters. In the typical shallow water, seasonal changes in acoustical conditions in the upper layer, of the depth of about 60-70 m, are observed. They are caused by variation of the annual meteorological conditions. Most often, in the deep water layer, acoustical conditions are stable throughout the year. However, in...
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Application of passive sampling technique in monitoring research on quality of atmospheric air in the area of Tczew, Poland.
PublicationThis paper presents the results of atmospheric air quality research in Tczew (adjacent to the Vistula River) on the content of BTEX compounds. Analytical procedure applied during the sampling of the analytes from the air used the passive sampling technique (diffusive passive sampler, Radiello®). For determination of BTEX compounds in atmospheric air, two-stage thermal desorption technique combined with gas chromatography (TD-GC-FID)...
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Interdisciplinary Design Teams in Poland - Architecture as a Tool for Preventing Hospital-Acquired Infections
PublicationHospital-acquired infections pose a problem, which directly affects the safe usage of healthcare facilities. On a global scale, the level of hospital-acquired infections (HAI) is estimated to affect 5–15% of those hospitalised. The World Health Organization (WHO) estimates that, on an annual basis, procedures preventing hospital-acquired infections consume 80 billion dollars [1]. In this context, it becomes important to create...
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Optimization of combined heat and power (CHP) market allocation: The case of Poland
PublicationCombined heat and power (CHP), that is production of electricity and useful heat in a single thermodynamic process, is a way of primary energy saving and emission reduction. Therefore, promotion of the electricity from high-efficiency cogeneration (CHP-E) was encouraged in the European Union. However, CHP-E promotion mechanisms proved low effectiveness in certain countries, like Poland, where the prices of certificates of origin...
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MODELOWANIE TURBINY WIATROWEJ Z DWOMA PRZECIWBIEŻNIE OBRACAJĄCYMI SIĘ WIRNIKAMI
PublicationW artykule przedstawiono sposoby modelowania dwuwirnikowej turbiny wiatrowej z wykorzystaniem technik Obliczeniowej Mechaniki Płynów. Omówiono uproszczone metody modelowania Actuator Disc i Actuator Line Method oraz aspekty związane z dokładnym odwzorowaniem turbiny na siatce obliczeniowej. Zaprezentowano przykładowe wyniki obliczeń turbiny dwuwirnikowej złożonej z wirników NREL o mocy nominalnej 5 MW każdy. Do wykonania badań...
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Entrepreneurship Vulnerability to Business Cycle. A New Methodology for Identification Pro-cyclical and Counter-cyclical Patterns of Entrepreneurial Activity
PublicationIn literature, there is ongoing discussion whether entrepreneurial activity, approximated by, for instance, changes in self-employment, tends to behave pro-cyclically, counter-cyclically or rather is a-cyclical. Thus far, both theoretical and empirical evidence, where various multiple methodological approaches are used, does not provide clear answer to the latter; while widely offered explanations are scattered and lack robustness....
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Global Competitiveness and Economic Growth: A One-Way or Two-Way Relationship?
PublicationThe Global Competitiveness Index is treated as a standard to measure the competitiveness of countries. Leaders look at it to make policy and resource allocation decisions because global competitiveness is expected to be related to economic growth. However, studies which analyze the empirical relationship between these two economic categories are very rare. It is still an open question in the literature whether economic growth can...
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Determination of total mercury in raw petrol using cold vapour atomic absorption spectrometry
PublicationPresence of different forms of mercury in petroleum based products may impair the proper operation of the equipment or led to poisoning of automotive catalysts. However much more important problem is environmental pollution with mercury emitted from different types of fossil fuels. Although the average mercury concentration in petroleum based products (automotive fuels) is on the level around 1 ppb, taking into account annual...
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Dynamics of productivity in higher education. Cross-European evidence based on bootstrapped Malmquist indices
PublicationThis study presents patterns of productivity change in a large set of 266 public higher education institutions (HEIs) from 7 European countries across the time period 2001-2005. We adopt consistent bootstrap estimation procedures to obtain confidence intervals for Malmquist indices of HEI productivity and their components. Consequently, we are able to assess statistical significance of the changes in HEIs' productivity, efficiency...
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An incorporation of contemporary daylight assessment methods into architecture and urban planning of residential areas in Poland
PublicationThis paper presents the preliminary results of the ongoing research focusing on daylight design methods for the urban planning of residential areas in Poland. The purpose of this research is to find out if modern daylight performance metrics and design methods can be beneficial to the process of urban residential planning. The paper presents a review of daylight guidelines derived from historic, Polish building regulations. A summary...
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Determination of benzo(a)pyrene content in PM10 using regression methods
PublicationThe paper presents an attempt of application of multidimensional linear regression to estimation of an empirical model describing the factors influencing on B(a)P content in suspended dust PM10 in Olsztyn and Elbląg city regions between 2010 and 2013. During this period annual average concentration of B(a)P in PM10 exceeded the admissible level 1.5-3 times. Conducted investigations confirm that the reasons of B(a)P concentration...
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Study on transmission quality in cellular 4G and 5G networks between 2019–2021: Impact of the COVID-19 pandemic on the level of provided services by operating base transceiver stations
PublicationThe COVID-19 pandemic has significantly limited user mobility, not least among students. Remote learning had a particular impact on resource allocation in relation to using terrestrial cellular networks, especially 4G systems in urban agglomerations. This paper presents the results of a quality evaluation of an outdoor environment, carried out between 2019 and 2021 on the campus of a technical university. Annual studies are conducted...
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Control Strategy of a Five-Phase Induction Machine Supplied by the Current Source Inverter With the Third Harmonic Injection
PublicationIn the five-phase induction machine (IM), it is possible to better use the electromagnetic circuit than in the three-phase IM. This requires the use of an adequate converter system which will be supplied by an induction machine. The electric drive system described, in this article, includes the five-phase induction machine supplied by the current source inverter (CSI). The proposed novelty—not presented previously—is the control...
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Yade-open DEM: an open-source software using a discrete element methodto simulate granular material
PublicationPurpose - YADE-OPEN DEM is an open source software based on the Discrete Element Method which uses object oriented programming techniques. The paper describes the softwarearchitecture.Design/methodology/approach - The DEM chosen uses position, orientation, velocity and angular velocity as independent variables of simulated particles which are subject to explicit leapfrog time-integration scheme (Lagrangian method). The three-dimensional...
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Synteza bezczujnikowego sterowania maszyną indukcyjną klatkową zasilaną z falownika prądu
PublicationSynteza bezczujnikowego sterowania maszyną indukcyjną klatkową zasilaną z falownika prądu stanowi cel niniejszej monografii. Praca zawiera podstawowe informacje na temat modelowania układu napędowego z maszyną indukcyjną klatkową zasilaną z falownika prądu. Przedstawiono informacje na temat linearyzacji nieliniowych obiektów. Na pod-stawie metody syntezy strukturalnej opracowano nowe transformacje do postaci zmien-nych multiskalarnych,...
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The risk assessment of adverse events of nursing activities as the element of quality management in healhcare
PublicationThe purpose of the paper is to present MedCARVER+Shock method and Pareto analysis and its usability for the risk assessment of adverse events of nursing activities. 888 activities carried out by all 190 nurses working at the District Hospital X located in Poland were taken into account. During the research the qualitative approach was used. As the result sixteen groups of nursing activities causing the highest risk of adverse events...
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Neutralising Responsibility: A Critical Analysis of an Airline’s Climate Disclosures
PublicationSustainability reporting provides companies with a medium through which they can communicate their non-financial impacts to stakeholders. The airline industry has been much at the centre of the climate change debate in recent years, which is why it is hardly surprising that airlines seek to take a proactive stance in such reporting. This study critically assesses how an airline based in the Scandinavian region constructs sustainability...
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Pipeline System for Heat Transportation from Nuclear Power Plant – an Optimizing Approach
PublicationOver the last few years heat piping insulation technology and pump systems efficiency have been significantly improved. Reduced thermal losses encourage heat transportation over long distances. It provides an opportunity for increasing thermodynamic efficiency of Nuclear Power Plants (NPPs) that are often located in rural areas because of safety issues. It can be achieved by Combined Heat and Power (CHP) generation, as heat produced...
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The influence of meteorological conditions and anthropogenic activities on the seasonal fluctuations of BTEX in the urban air of the Hanseatic city of Gdansk, Poland
PublicationThe results of studies conducted in Gdansk in the period from January to December 2013 and focused on the determination of BTEX in the atmospheric air are presented. At the stage of the isolation and/or enrichment of analytes from the gaseous medium, a passive sampling technique—Radiello® diffusive passive samplers, was applied. The time-weighted average annual concentration of benzene, toluene, ethylbenzene, and total xylenes...
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CO2 EMISSION TO THE ATMOSPHERE FROM CARBONATE WATERS: THE STUDY CASE OF THE LUBLIN UPLAND AND ROZTOCZE REGIONS
PublicationThe concentration of carbon dioxide dissolved in water (CO2(aq)) was measured in consecutive phases of the hydrological cycle. Its potentially possible degassing from groundwaters to the atmosphere was also assessed. The research was conducted in the area of occurrence of carbonate rocks of the Lublin Upland and Roztocze (SE Poland). The results of the measurements of CO2(aq) concentration varied as follows (min-max/mean): precipitation...
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GROWTH AND STRUCTURAL CHANGES IN TRANSITION COUNTRIES: THE CHICKEN OR THE EGG?
PublicationThe objective of this study is to test empirically the relationship between structural changes (changes in gross value added and employment) and economic growth. We used a panel Granger-causality analysis based on annual data for eight transition countries, covering the period 1995–2011. The main finding is that the causality relations analysed are heterogeneous processes and are identified more often...
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Structure of solvation water around the active and inactive regions of a type III antifreeze protein and its mutants of lowered activity
PublicationWater molecules from the solvation shell of the ice-binding surface are considered important for the antifreeze proteins to perform their function properly. Herein, we discuss the problem whether the extent of changes of the mean properties of solvation water can be connected with the antifreeze activity of the protein. To this aim, the structure of solvation water of a type III antifreeze protein from Macrozoarces americanus (eel...
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Non-destructive Testing of Wooden Elements
PublicationExamining the condition of wooden elements is crucial from the perspective of proper structure performance. If the deterioration in the internal wood condition, which displays no symptoms visible from the outside, is detected, the further spread of the deterioration can be prevented. Test results often point to the necessity of conducting repairs and, renovations, replacing the structure of wooden beams, or even substituting a...
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Impact of Climate Change on Groundwater Resources in a Young Glacial Multi-Aquifer System
PublicationThe aim of this study was to evaluate the trends of climate change on the Kashubian Lake District and to determine the impact of expected trends on groundwater resources. The analysis of trends in temperature and precipitation was conducted for the six-decade history of meteorological measurements at the weather station in Koscierzyna. The analysis shows the trend of temperature increase of +0.0182ºC/year. The highest increase...
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Seasonal changes of the concentrations of mineral forms of nitrogen and phosphorus in watercourses in the agricultural catchment area (Bay of Puck, Baltic Sea, Poland)
PublicationThe Baltic Region countries are obliged to meet the stringent limits of N and P discharge set by HELCOM for 2021. Area sources of pollution, including agriculture, are considered the main contributors of biogenic compounds. The Bay of Puck as an inner part of the Baltic Sea is particularly sensitive to eutrophication caused by nutrient in flow from agricultural lands. Rivers and streams inflowing to the Bay of Puck transport nitrogen...
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Energy Yield Generated by a Small Building Integrated Photovoltaic Installation
PublicationIn the recent years photovoltaic (PV) industry has experienced a major growth, caused by the ever present annual decrease in module production prices and the expanding awareness of the general public in terms of renewable energy. There are numerous ways to implement PV modules as an additional energy source for a building, be it mounted on the rooftop, or building integrated (BIPV). An analysis of BIPV consisting of 8 modules with...
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Effect of the North Atlantic Thermohaline Circulation on changes in climatic conditions and river flow in Poland
Publication: The purpose of this study is to find connections between the North Atlantic Thermohaline Circulation (NA THC), climate elements, such as cloud cover, precipitation, air temperature, sunshine duration, and relative humidity, and flow of rivers in Poland. The intensity of NA THC was characterized by the DG3L index, which was established to assess changes in the amount of heat transported by NA THC along with the transport of water...
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Comparative Analysis of Developed Rainfall Intensity–Duration–Frequency Curves for Erbil with Other Iraqi Urban Areas
PublicationRainfall Intensity–Duration–Frequency (IDF) relationships are widely used in water infrastructure design and construction. IDF curves represent the relationship between rainfall intensity, duration, and frequency, and are obtained by analyzing observed data. These relationships are critical for the safe design of flood protection structures, storm sewers, culverts, bridges, etc. In this study, the IDF curves and empirical IDF formulas...
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A comprehensive survey on low-cost ECG acquisition systems: Advances on design specifications, challenges and future direction
PublicationAvailability of low-cost, reliable, and portable Electrocardiography (ECG) devices is still very important in the medical world today. Despite the tremendous technological advancement, Cardiovascular Diseases (CVDs) remain a serious health burden claiming millions of lives on an annual basis globally. This is more prevalent in Low and Middle-Income Countries (LMICs) where there are huge financial instability and lack of critical...
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Gender and Labor Market Situation among Technical University Graduates in Poland
PublicationThe aim of article is to analyse the professional situation of technical university graduates in Poland, focusing on the gender as the key impact factor. The research problem was to examine the influence of gender on the employee’s professional situation among technical university graduates in Poland. Empirical data was gained as a result of six annual quantitative research projects, conducted in the years 2012‑2017 on a total...
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Acoustic lifecycle study of the double-layer porous asphalt on E4 in Huskvarna, Sweden
PublicationIn 2010 a double-layer porous asphalt concrete (DPAC) pavement was constructed on the E4 motorway through the Swedish city Huskvarna. Earlier experience in Sweden indicated that it was feasible to obtain a high initial noise reduction but due to the widespread use of studded tires in winter, clogging and ravelling created losses of around 2 dB per year, with an expected acoustical lifetime of only 3 years. However, the improved...
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Seafloor characterisation using multibeam data: sonar image properties, seabed surface properties and echo properties
PublicationIn the paper, the approach to seafloor characterisation is presented. The multibeam sonars, besides their well verified and widely used applications like high resolution bathymetry and underwater object detection and imaging, are also the promising tool in seafloor characterization and classification, having several advantages over conventional single beam echosounders. The proposed approach relies on the combined, concurrent use...
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UWB Microstrip Antennas on a Cylindrical Surfaces
PublicationConformal antennas are becoming popular due to their many advantages and possibilities of applications they offer. The advantages of using antennas with a curved surface arise not only from the possibility of integrating them with the object on which they are mounted on but also from the increase, relatively to planar antennas, of their visible angular range. The circular antenna arrays, or arrays of radiators located on the surface...
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SZACOWANIE ZAWARTOŚCI BENZO(a)PIRENU W PYLE ZAWIESZONYM PM10 W AGLOMERACJI TRÓJMIEJSKIEJ ZA POMOCĄ WIELOWYMIAROWEJ REGRESJI LINIOWEJ=ESTIMATION OF BENZO(A)PYRENE CONTENT IN SUSPENDED DUST PM10 IN TRI-CITY AGGLOMERATION USING MULTIDIMENSIONAL LINEAR REGRESSION
PublicationW pracy przedstawiono próbę oszacowania przy pomocy wielowymiarowej regresji liniowej modelu empirycznego opisującego czynniki wpływające na zawartość B(a)P w pyle zawieszonym PM10 w Aglomeracji Trójmiejskiej w latach 2008-2011. Na przestrzeni tych lat średnioroczne stężenie B(a)P w PM10 wzrosło ponad dwukrotnie i ponad trzykrotnie przewyższa poziom docelowy. Z przeprowadzonych analiz wynika, że główną przyczyną wzrostu stężenia...
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The Analysis of Working Parameters Decrease in Photovoltaic Modules as a Result of Dust Deposition
PublicationThe aspect of dust accumulation on the surface of photovoltaic (PV) modules should be thoroughly understood in order to minimize possible obstacles affecting energy generation. Several elements affect the amount of pollutant gathered on the surface of a solar device, mainly its localization, which is irreversibly linked to factors such as annual rainfall, occasional snow coverage, or, in a dry climate, increased blow of dust during...
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Interannual Variability of the GNSS Precipitable Water Vapor in the Global Tropics
PublicationThis paper addresses the subject of inter-annual variability of the tropical precipitable water vapor (PWV) derived from 18 years of global navigation satellite system (GNSS) observations. Non-linear trends of retrieved GNSS PWV were investigated using the singular spectrum analysis (SSA) along with various climate indices. For most of the analyzed stations (~49%) the GNSS PWV anomaly was related to the El Niño Southern Oscillation...
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Relationship between wages, labour productivity and unemployment rate in new EU member countries
PublicationThe main aim of this article is to find out the extent to which relative labour productivity and relative unemployment rate changes determine relative wage changes. We use average annual macro-data for the period 2002-2013 for Poland and other 5 new EU members: Estonia, Hungary, Slovak, Czech Republic and Slovenia. Using Poland as benchmark, rst we examine the correlation between wage, productivity and unemployment rate changes...
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Wykorzystanie analizy kosztów w zarządzaniu szpitalem publicznym
PublicationProblemy z finansowaniem opieki zdrowotnej obserwowane są praktycznie na całym świecie. Jako przyczyny wzrostu wydatków uważa się głównie starzenie się populacji, złożoną naturę współczesnych chorób i szerokie wykorzystywanie kosztownych technologii. Systemy opieki zdrowotnej na całym świecie stają przed trudnym wyzwaniem zwiększenia efektywności, co oznacza kontrolowanie kosztów, przy jednoczesnym zapewnieniu wysokiej jakości...
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Assessment of the Current Potential of Hydropower for Water Damming in Poland in the Context of Energy Transformation
PublicationThe present paper indicates that hydropower, including small hydropower plants (SHPs), may play a very important role in Poland’s energy transformation in the near future. The development of SHPs may also increase water resources in the steppe Poland. Additionally, the aim of the present research is to conduct the PEST analysis of SHPs in Poland, taking into account the SHP potential. For the first time, maps showing the power...
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Assessment of the Impact of GNSS Processing Strategies on the Long-Term Parameters of 20 Years IWV Time Series
PublicationAdvanced processing of collected global navigation satellite systems (GNSS) observations allows for the estimation of zenith tropospheric delay (ZTD), which in turn can be converted to the integrated water vapour (IWV). The proper estimation of GNSS IWV can be affected by the adopted GNSS processing strategy. To verify which of its elements cause deterioration and which improve the estimated GNSS IWV, we conducted eight reprocessings...
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The impact of freeze-thaw processes on a cliff recession rate in the face of temperate zone climate change
PublicationFreeze-thaw action is a common type of geomorphological processes eroding cliff faces in the temperate climate zone. In our previous study, we assessed the geomorphological effects of freeze-thaw fluctuations occurring within the cliff of Jeziorsko Reservoir (central Poland). Based on those findings, we have now determined the number of freeze-thaw cycles to assess their historical impact on the studied cliff. We have also traced...
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Lateral forces determine dimensional accuracy of the narrow‑kerf sawing of wood
PublicationThe shrinking global forest area limits the supply of industrially usable raw resources. This, in combination with the ever‑increasing consumption of timber due to population growth can lead to the lack of a positive balance between the annual volumetric growth and consumption of wood. An important innovation toward increasing environmental and economic sustainability of timber production is to reduce the volume of wood residues...
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Influence of dissolved organic nitrogen on surface waters
PublicationThe aim of this study was to determine the susceptibility of dissolved organic nitrogen (DON) contained in biologically treated wastewater disposed from municipal wastewater treatment plants (WWTPs) to biodegradability and bioavailability in a water environment. Additionally an evaluation was performed of the participation of this organic nitrogen fraction, including bioavailable DON (bDON), in the nitrogen balance for the Baltic...
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BTEX concentration levels in urban air in the area of the Tri-City agglomeration (Gdansk, Gdynia, Sopot), Poland
PublicationThe paper presents and discusses the results of atmospheric air quality research conducted in 2012 with reference to the level of BTEX compounds in the Tri-City agglomeration—Gdansk, Gdynia, and Sopot (northern Poland). At the stage of BTEX sampling from the ambient air, Radiello® diffusive passive samplers were applied. The annual time-weighted average concentrations for benzene, toluene, ethylbenzene, and xylenes (BTEX) in the...
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IDENTIFICATION AND COMPARATIVE ANALYSIS OF FACTORS INFLUENCING ROAD SAFETY IN US REGIONS AND IN POLISH VOIVODESHIPS
PublicationAnalyses of road safety at national level have been run for many years and large number of publications concerning them appeared so far. How interdisciplinary the issue is, has been shown by literature studies done by the author of the paper. It appears that economists, mathematicians, doctors as well as engineers have studied the issue. It is not an easy one, as results of many analyses lead to conflicting conclusions and...
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Thermodynamic and economic analysis of nuclear power unit operating in partial cogeneration mode to produce electricity and district heat
PublicationThis paper presents the methodology of techno-economic analysis for a nuclear unit operating in partial cogeneration mode and its application for the case study: a nuclear power plant planned in Poland. The research objectives were: to propose EPR, AP1000 and ESBWR nuclear condensing-extraction turbine systems modifications required for operation in cogeneration, to determine optimal heat production and heat transport line (HTL)...
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Challenges and recent advances in bio-based isocyanate production.
PublicationPolyurethanes (PUs) are key players in the plastics industry. According to the Global Polyurethane Market (2019–2023), their value in the global market reached $95.13 billion in 2019 and is expected to grow at a compound annual growth rate of 12%. This is in line with the increase in the number of research papers and patents on the synthesis and application of petroleum-based PUs (P-PUs) and biomass or green PUs (G-PUs) (from 67 657...