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The selected hydrotechnical conditions of the Dnieper – Bug Channel and the Pripyat River in the development of the International Waterway E40
PublicationInternational waterway E40 (MDW E40) is included in the network of inland waterways of transnational importance. It is a link between two areas: the Baltic Sea and the Black Sea. E40 route runs through three countries: Poland, Belarus and Ukraine. The article presents the results of the study on the analysis of two very important sections of the MDW E40 on the Belarusian section, it is:. the Dnieper – Bug Channel and the Pripy...
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INFLUENCE OF DATA NORMALIZATION ON THE EFFECTIVENESS OF NEURAL NETWORKS APPLIED TO CLASSIFICATION OF PAVEMENT CONDITIONS – CASE STUDY
PublicationIn recent years automatic classification employing machine learning seems to be in high demand for tele-informatic-based solutions. An example of such solutions are intelligent transportation systems (ITS), in which various factors are taken into account. The subject of the study presented is the impact of data pre-processing and normalization on the accuracy and training effectiveness of artificial neural networks in the case...
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Studies on Treatment of Bitumen Effluents by Means of Advanced Oxidation Processes (AOPs) in Basic pH Conditions
PublicationThe paper presents the results of studies on chemical treatment of effluents from production of bitumen of petroleum origin. Due to the presence of sulfide ions, the pH of these effluents is strongly alkaline. Several Advanced Oxidation Processes (AOPs) were studied, including the use of hydroxyl and sulfate radicals oxidants, the hydrodynamic cavitation as well as sonocavitation. The best processes allow to obtain 45% reduction...
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Studies on treatment of bitumen effluents by means of Advanced Oxidation Processes (AOPs) in basic pH conditions
PublicationThe paper presents the results of studies on chemical treatment of effluents from production of bitumen of petroleum origin. Due to the presence of sulfide ions, the pH of these effluents is strongly alkaline. Several Advanced Oxidation Processes (AOPs) were studied, including the use of hydroxyl and sulfate radicals oxidants, the hydrodynamic cavitation as well as sonocavitation. The best processes allow to obtain 45% reduction...
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Revitalization of the Narrow-Gauge Żuławy Commuter Railway and its effect on shipping conditions in the Vistula delta
PublicationThe article presents the Żuławy Access Railway and the effect of its revitalization on the change of navigational conditions in the Vistula delta. One of the problems analyzed in the article is the intersection of two different transport branches - the inland waterway and rail transport branches. A solution to the problem of their functioning is presented, without any major restrictions. Possible changes in navigational conditions...
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Modeling of the Two-Dimensional Flow Caused by Sea Conditions and Wind Stresses on the Example of Dead Vistula
PublicationThe article presents the results of two-dimensional modeling of flows caused by the sea conditions and wind stresses on the example of Dead Vistula. Based on the available bathymetric data, a numerical model of the river section was created, which was supplemented with data on the position of the water table depending on hydrometeorological conditions. To describe the flow field in steady conditions, a simplified model of two-dimensional...
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Electrochemical degradation of textile dyes in a flow reactor: effect of operating conditions and dyes chemical structure
PublicationIn this study, electrochemical oxidation of five azo dyestuffs (Yellow D-5GN, Red D-B8, Ruby F-2B, Blue D-5RN, Black DN), that are widely used in the textile industry, was investigated in a flow reactor. BDD electrode with a high boron doping level (C/B = 10 000) was prepared and used. Two configurations of reactor were considered, i.e., one with the undivided cell, and the other with the cell divided by anodic and cathodic compartments....
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The impact of the shape of deep drilled well screen openings on the filtration process in full saturation conditions
PublicationThe authors propose a supplementary method of modelling seepage flow around the deep drilled well screen. The study applies 3D numerical modelling (FEM) in order to provide an in-depth analysis of the seepage process. The analysis of filtration parameters (flow distribution q(x,t) and pressure distribution p) was conducted using the ZSoil.PC software system. The analysis indicates that the shape of perforation is of secondary importance...
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Numerical studies on the influence of selected construction features and road conditions on the performance of road cable barriers
PublicationCable barriers are commonly used on Polish roads, including motorways and local roads. Their main elements are pre-stressed wire ropes, which are usually anchored at two ends in concrete blocks buried in the soil. In this work numerical studies concerning the influence of selected construction features and parameters of the vehicle motion on the performance of cable barriers were performed. Numerical simulations are a useful tool...
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Results from tests on bolted connection components for evaluation of friction coefficient in various contact conditions
PublicationThe main purpose of the work was the analysis and evaluation of the self-locking quality of a bolted joint covered with Xylan 1070 coating, with comparison to the classic bolts lubricated with Molykote compound during assembly. The second part of the work was the verification of the compliance of the bolts and nuts used in the installation with the ASME B1.1 norm.
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Effects of Laser Remelting at Cryogenic Conditions on Microstructure and Wear Resistance of the Ti6Al4V Alloy Applied in Medicine
PublicationThe titanium and its alloys can be subjected to surface treatment, including laser treatment. In this work a new laser treatment at cryogenic conditions of Ti6Al4V alloy has been described. The work has been aimed at establishing whether such surface treatment could be suitable for implants working under wear in biological corrosive environment. The remelting has been made with the use of CO2 continuous work laser at laser power...
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One Year Evaluation of Material Properties Changes of Polylactide Parts in Various Hydrolytic Degradation Conditions
PublicationBiodegradable biocompatible materials are widely used in medical applications. Determining the possibility of using biodegradable materials depends on determining the changes in their parameters over time due to degradation. The current scientific research on biodegradable materials has presented results based on research methods characterized by the different geometry and cross-section size of the specimen, type of degradation...
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Effects of biotransport and hydro-meteorological conditions on transport of trace elements in the Scott River (Bellsund, Spitsbergen)
PublicationThe shaping of surface water chemistry in the Svalbard Archipelago is strongly dependent on the geology of the catchment and the process of long-range transport of atmospheric pollutants (LRATP). It was found that the dissolved trace elements in the Scott River, which catchment is characterized by a decreasing degree of glaciation, were of the natural origin (i.a. weathering and dissolution of local geological substratum). The...
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Analysis of the influence of external conditions on temperature readings in thermograms and adaptive adjustment of the measured temperature value
PublicationMeasuring human temperature is a crucial step in preventing the spread of diseases such as COVID-19. For the proper operation of an automatic body temperature measurement system throughout the year, it is necessary to consider outdoor conditions. In this paper, the effect of atmospheric factors on facial temperature readings using infrared thermography is investigated. A thorough analysis of the variation of facial temperature...
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Convenient and efficient N-methylation of secondary amines under solvent-free ball milling conditions
PublicationIn the present work, we report the development of a rapid, efcient, and solvent-free procedure for the N-methylation of secondary amines under mechanochemical conditions. After optimization of the milling parameters, a vibrational ball mill was used to synthesize 26 tertiary N-methylated amine derivatives in a short time of 20 min (30 Hz frequency) and high yields ranging from 78 to 95%. An exception was compounds having a hydroxyl...
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Minimization of a ship's magnetic signature under external field conditions using a multi-dipole model
PublicationThe paper addresses the innovative issue of minimizing the ship's magnetic signature under any external field conditions, i.e., for arbitrary values of ambient field modulus and magnetic inclination. Varying values of the external field, depending on the current geographical location, affect only the induced part of ship's magnetization. A practical problem in minimizing the ship signature is separating permanent magnetization...
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Analysis of Investments in RES Based on the Example of Photovoltaic Panels in Conditions of Uncertainty and Risk—A Case Study
PublicationThe aim of this study is to examine the profitability of investment in a photovoltaic microinstallation, to analyze the impact of legal changes on its profitability, and to perform a sensitivity analysis of the investment profitability to energy price changes. The novelty of the research applies to the financial analysis of two legal systems of discount called net-metering and net-billing. The two systems and the change in energy...
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Conditions for increasing the recognition of degradation in thermal-flow diagnostics, taking into account environmental legal aspects
PublicationThe ever-increasing demand for electricity and the need for conventional sources to cooperate with renewable ones generates the need to increase the efficiency and safety of the generation sources. Therefore, it is necessary to find a way to operate existing facilities more efficiently with full detection of emerging faults. These are the requirements of Polish, European and International law, which demands that energy facilities...
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Homogeneous nucleation rate of methane hydrate formation under experimental conditions from seeding simulations
PublicationIn this work, we shall estimate via computer simulations the homogeneous nucleation rate for the methane hydrate at 400 bars for a supercooling of about 35 K. The TIP4P/ICE model and a Lennard-Jones center were used for water and methane, respectively. To estimate the nucleation rate, the seeding technique was employed. Clusters of the methane hydrate of different sizes were inserted into the aqueous phase of a two-phase gas–liquid...
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Flood Classification in a Natural Wetland for Early Spring Conditions Using Various Polarimetric SAR Methods
PublicationAbstract--- One of the major limitations of remote sensing flood detection is the presence of vegetation. Our study focuses on a flood classification using Radarsat-2 Quad-Pol data in a natural floodplain during leafless, dry vegetation (early spring) state. We conducted a supervised classification of a data set composed of nine polarimetric decompositions and Shannon entropy followed by the predictors' importance estimation to...
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Modeling process of planning finished product sales volumes at industrial enterprises in modern economic conditions
PublicationThis article presents improving the existing system of planning finished products sales volumes. The influencing factors of the sales volumes in modern economic conditions have been determined: falling world oil prices, the reduction of pipe consumption in the domestic market, the global pandemic. The algorithm of planning finished products sales volumes has been constructed. Calculations based on the Holt forecasting method has...
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Logistical Aspects of Energy Conversion Efficiency in Marine Steam Power Plants in Off-Design Conditions
PublicationThe paper presents logistical aspects of energy conversion efficiency in off-design conditions. The main part of the article is based on results of thermodynamic calculation for large propulsion steam turbine under partial loads. Calculations are made on extended mathematical model of two proposed steam turbine thermodynamic cycles using Stodola’s cone law. The conclusion based on calculation re-sults contains importance of off-design...
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Harmonic analysis of the current of an electric system simulating the electrode process in conditions of linearly changing potential
PublicationAnalizowany był prąd elektrycznego modelu symulującego pierwszorzędową reakcję elektrodową zachodzącą w warunkach liniowo zmieniającego się potencjału z nałożonym sygnałem sinusoidalnym. Pokazano, że transformacja Fouriera nie odzwierciedla zmian amplitudy składowych komponentów w funkcji potencjału. Także matematycznie wykazano, że zastosowanie transformacji Gabora do analizy spektralnej pozwala uzyskać poprawną dekompozycję częstotliwościową....
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Geometrical conditions of saw blade`s entering into and going out of material during wood cutting
PublicationW pracy przedstawiono analizę geometrycznych warunków wejścia i wyjścia ostrza piły z materiału obrabianego przy przecinaniu drewna. Przedstawiono czasowy i przestrzenny rozkład geometrycznych parametrów wejścia i wyjścia ostrza i ich wpływ na trwałość ostrzy i dokładność przecinania.
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The formal safety assesment in conforming to chosen vessel's type on the ground of hydromechanic characteristics in critical conditions.
PublicationTragedia jednego ze statków typu ro-ro pokazała podatność tego typu statków na utratę stateczności, przewrócenie a w ostateczności zatonięcie. Wszystkie ro-rowce charakteryzują się małym zanurzeniem, a wynurzona część kadłuba podatna jest na działanie wiatru. Jeżeli dodatkowo w takich warunkach dochodzi element nieprawidłowego rozmieszczenia pojazdów i ich słabego zamocowania to groźba przesunięcia ładunku staje się realna. W konsekwencji...
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Country‐level and individual‐level predictors of men's support for gender equality in 42 countries
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Paper profits or real money? Trading costs and stock market anomalies in country ETFs
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The convergence of gender wage differences - myth or fact - multi country multi sector analysis
PublicationThe Becker’s theory of discrimination predicts that in the long run the gender wage differences should disappear. In our empirical analysis we verify the testable implications of this mode considering the hypothesis of gender wage gap convergence. The study takes into account 31 sectors in 13 European countries for the period between 1970 and 2005. We distinguish between wages paid to different groups of workers classified according...
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Piotr Lorens — Challenges for Spatial Development and Planning – Outlook from a Post-socialist Country
PublicationThe article includes reflections regarding challenges for spatial development as seen from the perspective of the transformation country. The perspective of the Polish development challenges are taken into account.
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Transformational Leadership and Acceptance of Mistakes as a Source of Learning: Poland-USA Cross-Country Study
PublicationThis study explores the influence of transformational leadership on internal innovativeness mediated by mistakes acceptance, including country and industry as factors to be considered and gender and risk-taking attitude as moderators. General findings, primarily based on the US samples (healthcare, construction, and IT industry), confirmed that transformational leadership and internal innovativeness are mediated by mistakes acceptance...
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Molecular dynamics of fentanyl bound to μ-opioid receptor
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Fate of Dipole-Bound Anion States when Hydrated
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Is the p-chloroaniline anion bound almost entirely by correlation?
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Lower bound on the weakly connected domination number of a tree
PublicationPraca dotyczy dolnego ograniczenia liczby dominowania słabo spójnego w drzewach (ograniczenie ze względu na ilość wierzchołków i ilość wierzchołków końcowych w drzewie).
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On the lower smoothing bound in identification of time-varying systems
PublicationIn certain applications of nonstationary system identification the model-based decisions can be postponed, i.e. executed with a delay. This allows one to incorporate in the identification process not only the currently available information, but also a number of ''future'' data points. The resulting estimation schemes, which involve smoothing, are not causal. Assuming that the infinite observation history is available, the paper...
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On trees attaining an upper bound on the total domination number
PublicationA total dominating set of a graph G is a set D of vertices of G such that every vertex of G has a neighbor in D. The total domination number of a graph G, denoted by γ_t(G), is the minimum cardinality of a total dominating set of G. Chellali and Haynes [Total and paired-domination numbers of a tree, AKCE International Journal of Graphs and Combinatorics 1 (2004), 69-75] established the following upper bound on the total domination...
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Distinguishing views in symmetric networks: A tight lower bound
PublicationThe view of a node in a port-labeled network is an infinite tree encoding all walks in the network originating from this node. We prove that for any integers n ≥ D ≥ 1, there exists a port-labeled network with at most n nodes and diameter at most D which contains a pair of nodes whose (infinite) views are different, but whose views truncated to depth Omega( D log(n/ D )) are identical.
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A few steps more towards NPT bound entanglement
PublicationIn this paper, existence of bound entangled states with nonpositive partial transpose (NPT) is considered. As one knows, existence of such states would in particular imply nonadditivity of distillable entanglement. Moreover, it would rule out a simple mathematical description of the set of distillable states. The particular state, known to be 1-copy nondistillable and supposed to be bound entangled, is considered. The problem of...
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Lower bound on the distance k-domination number of a tree
PublicationW artykule przedstawiono dolne ograniczenie na liczbę k-dominowania w drzewach oraz scharakteryzowano wszystkie grafy ekstremalne.
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On well-posedness of the first boundary-value problem within linear isotropic Toupin–Mindlin strain gradient elasticity and constraints for elastic moduli
PublicationWithin the linear Toupin–Mindlin strain gradient elasticity we discuss the well-posedness of the first boundary-value problem, that is, a boundary-value problem with Dirichlet-type boundary conditions on the whole boundary. For an isotropic material we formulate the necessary and sufficient conditions which guarantee existence and uniqueness of a weak solution. These conditions include strong ellipticity written in terms of higher-order...
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Measurements of the heat of hydration released by concrete specimens cured under adiabatic conditions
Open Research DataThe DataSet contains measurements of heat of hydartion of concrete cubes (150 x 150 x 150 mm) cured under adiabatic conditions. The specimens were moulded from six types of concrete mixtures produced in the laboratory conditions. Mix #1: Portland cement CEM I 42.5R and gravel aggregate, mix #2: CEM I 42.5R and basalt aggregate, mix#3: Portland-composite...
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A Bi-Objective Portfolio Optimization with Conditional Value-at-Risk
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Conditional simulation of spatiotemporal random fields of environmental contamination
PublicationArtykuł przedstawia metodę warunkowego modelowania przestrzenno-czasowych pól losowych w zagadnieniach środowiska naturalnego. Metoda ta może być wykorzystana do prognozy zanieczyszczenia w wybranych punktach w danym czasie na podstawie pomiarów wykonanych w innych miejscach i/lub w innym czasie. Analizę przeprowadzono na przykładzie zanieczyszczenia gruntu metalami ciężkimi.
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Investigation of oleophilic nature of straw sorbent conditioned in water.
PublicationPrzedyskutowany został potencjał absorpcyjny słomy jęczmiennej kondycjonowanej w wodzie. W odniesieniu do właściwości powierzchni zewnętrznej oraz wewnętrznej łodygi i liści zostały zmierzone kąty zwilżania dla wody i dekanu zarówno dla słomy suchej, jak i mokrej.
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Number of work permits issued in 2008-2018 by migrant's country of origin
Open Research DataThe scale of the influx of economic migrants to Poland can be proved by data referring to documents enabling legal work, including work permits. In 2018, the most frequently applied for work permit for citizens of eight countries presented in the dataset. The table contains data on the number of permits issued in the years 2008-2018.
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Three-dimensional structure of wave-induced momentum flux in irrotational waves in combined shoaling-refraction conditions
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Effect of preparation conditions and promoters on the structure and activity of the ammonia decomposition reaction catalyst based on nanocrystalline cobalt
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Effect of nanosilver (nAg) on disinfection, growth, and chemical composition of young barley leaves under in vitro conditions
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Sustainable Management of the Offer of Cultural Institutions in the Cross-Border Market for Cultural Services – Barriers and Conditions
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Weather Conditions, Orchard Age and Nitrogen Fertilization Influences Yield and Quality of ‘Łutówka’ Sour Cherry Fruit
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