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Modular Approach for Modelling Warming Up Process in Water Installations with Flow-Regulating Elements
PublicationThe paper presents a new method for modelling the warming up process of a water system with elements regulating the flow in a stochastic manner. The paper presents the basic equations describing the work of typical elements which the water installation is composed of. In the proposed method, a new computational algorithm was used in the form of an iterative procedure enabling the use of boundary conditions that can be stochastically...
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Sliding bearings with sintered bronze bush lubricated by contaminated water with solid particles – Theoretical and experimental studies
PublicationSliding journal bearings lubricated with water coming directly from the environment are a solution used in shipbuilding, pumps and hydropower. However, the working fluid or surrounding water cannot always be filtered because of design limitations, which often causes the problem of premature wear of these sensitive bearings. The research conducted made it possible to assess the wear of sliding bearings lubricated with water containing...
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Adsorption-assisted transport of water vapour in super-hydrophobic membranes filled with multilayer graphene platelets
PublicationThe effects of confinement of multilayer graphene platelets in hydrophobic microporous polymeric membranes are here examined. Intermolecular interactions between water vapour molecules and nanocomposite membranes are envisaged to originate assisted transport of water vapour in membrane distillation processes when a suitable filler-polymer ratio is reached. Mass transport coefficients are estimated under different working conditions,...
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Comparison of bacterial production in the water column between two Arctic fjords, Hornsund and Kongsfjorden (West Spitsbergen)
PublicationBacterial production and the accompanying environmental factors were measured in the water columns of two Arctic fjords during the cruise in July and August 2013. Water samples were collected at six stations located in the central part of Hornsund and Kongsfjorden. In Hornsund, where average water temperatures were 1.25-fold lower than in Kongsfjorden, the bacterial production was twice as high (0.116 ± 0.102 vs 0.05 ± 0.03 mg...
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The influence of polymer bearing material and lubricating grooves layout on wear of journal bearings lubricated with contaminated water
PublicationThe goal of the present paper is to investigate wear properties of journal sliding bearing operating in the conditions of contaminated water lubrication. Several bearing materials and bearing sleeve designs (differing in the axial grooves position and their shape) were tested experimentally under typical operating conditions in a dedicated test rig, which was equipped with a lubricating system, enabling lubrication with contaminated...
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Determination of Selected Organic Acids in Animal Farm Water Samples by Ion Chromatography
PublicationLow molecular mass carboxylic acids (LCAs) occur in many environmental compartments due to natural processes and human activity. They are an important group of organic pollutants of waste water that mainly includes, volatile fatty acids, and also dicarboxylic, aromatic, hydroxy- and ketoacids. LCAs are present in the environment at concentrations between 1 to 5000 ppm and different methods have been reported for their determination...
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Communication: Inside the water wheel: Intrinsic differences between hydrated tetraphenylphosphonium and tetraphenylborate ions
PublicationTetraphenylphosphonium tetraphenylborate (TPTB) is a common reference electrolyte in physical chemistry of solutions allowing for a convenient partitioning of thermodynamic properties into single-ion contributions. Here, we compute on the basis of ab initio molecular dynamics simulations the infrared (IR) spectra for hydrated constituent ions of the TPTB assumption. Using spectral decomposition techniques, we extract important...
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Interaction Between Storm Water Conduit And Surface Flow For Urban Flood Inundation Modelling
PublicationRapid development of urban areas always comes with great side effects. One of them is the occurrence of urban floods. Growth of impervious surfaces in cities leads to increasing run-off values. This together with difficulties connected with sewage modernization in cities marks urban inundations as being one of the most important issues concerning urban water. Accurate prediction of a phenomenon is difficult as it is highly dependent...
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Influence of iron content on water uptake and charge transport in BaCe0.6Zr0.2Y0.2−xFexO3−δ triple-conducting oxides
PublicationIn this work, we studied the BaCe0.6Zr0.2Y0.2−xFexO3−δ system which belongs to the triple-conducting oxides (TCOs) group. The electrochemical properties of BaCe0.6Zr0.2Y0.2−xFexO3−δ were investigated using electrochemical impedance spectroscopy (EIS) and the water uptake was analyzed using thermogravimetry (TG). All investigated materials exhibited water uptake, with proton concentration increasing with decreasing iron content....
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Feedback control of water quality
PublicationSformułowano problem sterowania jakością wody w sieciach wodociągowych i następnie zaproponowano podejście do projektowania sterowania stężeniem chloru w takich sieciach, bazujący na estymacji parametrów oraz sterowaniu adaptacyjnym. Podejście wykorzystuje założenie, że w sieci wodociągowej istnieją punkty wstrzykiwania chloru. Zależność typu wejście-wyjście pomiędzy stężeniem chloru w węźle dozowania i monitorowania jest modelowana...
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Sampling water and aqueous solutions
PublicationW pracy przedstawiono: klasyfikację technik pobierania próbek ciekłych; bu-dowę szerokiej gamy urządzeń (próbników) do pobierania próbek różnego typumediów ciekłych; sposoby konserwacji próbek; terminologię związaną z tymetapem procedur analitycznych.
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Degradation of polyurethanes in sea water
PublicationOceniono degradowalność różnych poliuretanów w wodzie morskiej Bałtyku. Porównano te dane z wynikami stopnia degradacji poliuretanów w wodzie morskiej z dodatkiem azydku sosowego. Ocenę stopnia degradacji przeprowadzano na podstawie pomiarów zmian masy, właściwości mechanicznych i morfologii przed i po procesie degradacji. Wykazano, że różna podatność na degradację poliuretanów w wodzie morskiej związana jest z ich odmiennym stopniem...
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Preservation and storage of water samples
PublicationOd momentu pobrania próbki do wykonania tej analizy wody mogą zmieniać swoje właściwości na skutek zachodzących w nich procesów chemicznych, fizycznych, czy też biologicznych. W pracy omówiono zmiany mogące zachodzić w próbkach wodnych oraz przyczyny ich występowania. Szczególną uwagę zwrócono na reakcje chemiczne, procesy fizykochemiczne, reakcje biochemiczne i fotochemiczne. Przedstawiono również techniki konserwacji próbek wód...
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Accumulation of water on the vehicle deck
PublicationPodano matematyczny model gromadzenia się wody na pokładzie garażowym statków ro-ro w stanie awaryjnym i wypiętrzania się wody ponad poziom wody zaburtowej w wyniku falowania morza. Wypiętrzanie to ma charakter losowy. Podano teoretycznie wartość średnią i wariancję tegoż wypiętrzenia.
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Storm Water Treatment in TWs
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Preservation and Storage of Water Samples
PublicationOpisano metody utrwalania i przechowywanie próbek wody w celu oznaczenia zwiazków nieorganicznych, przedyskutowano wady i zalety poszczególnych metod. Omówiono utrwalanie i przechowywanie próbek wody przed wykonaniem analizy specjacyjnej związków arsenu, chromu, rteci, selenu i cyny. Omówiono również utrwalanie i przechowywanie próbek wody przy oznaczaniu związków organicznych.
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Magnetic photocatalysts for water treatment
PublicationThe concept of magnetic photocatalysts with separation function requires ferromagnetic material with high magnetic susceptibility to an external magnetic field to enable recycling of composite nanoparticles. Currently, much attention is devoted to functionalization of photocatalyst using MFe2O3, where M =Fe, Zn, Co, Mn. However direct contact between photocatalyst and magnetic iron oxide particles leads to photodissolution of iron...
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Processes and the Resulting Water Quality in the Medium size Turawa Storage Reservoir after 60 Year Usage
PublicationThe Turawa reservoir built on the Mała Panew river is one of important storage reservoirs in Poland. Quite many physico-chemical parameters of water in the reservoir itself and also in the reservoir inflowing rivers at different times of the year were measured and compared. The changes of water characteristics as well as their reasons and consequences were discussed.
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Optimised Robust Placement of Hard Quality Sensors for Robust Monitoring of Quality in Drinking Water Distribution Systems
PublicationA problem of optimised robust placement of the hard quality sensors in Drinking Water Distribution Systems under several water demand scenarios for robust quality monitoring is formulated. Numerical algorithms to solve the problem are derived. The optimality is meant as achieving at the same time a desired trade off between the sensor capital and maintenance costs and resulting robust estimation accuracy of the monitoring algorithm...
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Time-varied-gain correction for digital echosounders. W: [CD-ROM] Forum A-custicum Sevilla 2002. 3rd European Congres on Acoustics. XXXIII Spanish Congress on Acoustics - TECNIACUSTICA 2002. European and Japanese Symposium on Acoustics. Sevilla, Spain 16-20 September 2002. Madrid: Sociedad Espano- la de Acustica**2002 vol. 33, [6 s.] 6 rys. bibliogr. 2 poz. ISBN: 84-87985-06-8 Special Issue of the Journal Revista de Acustica, vol.XXXIII, ano 2002. Korekcja zasięgowej regulacji wzmocnienia dla echosond cyfrowych.
PublicationW pracy przedstawiono modyfikację statystycznej metody EMS stosowanej w za-gadnieniach odwrotnych, polegającą na iteracyjnym rozwiązaniu równania Fred-holma. Pokazano jej zastosowanie do pośredniej estymacji siły celu ryb sto-sowanej dla danych pozyskanych przez hydrakustyczne systemy jednowiązkowewykorzystywane w przeszukiwaniach akustycznych. Wyniki porównano z rezulta-tami uzyskanymi technikami dekompozycji SVD.
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Comparison of single microjet cooling with water, ethanol and HFE7100 as test fluids
PublicationThe paper presents the investigation of a single microjet cooling forming an thin liquid film on the impingement surface of specially designed rig. The basis of microjet technology is to produce laminar jets, which when impinging the surface have a very high kinetic energy at the stagnation point. Applied technology of jet production can result with the size of jets ranging from 20 to 500μm in breadth and 20 to 100μm in width....
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Reject water and landfil leachate treatment with hydrophyte method - preliminary results
PublicationTreatment of landfill leachate (LL) and reject water (RWC) from dewatering of digested sludge in WWTPs have become one of the actual problems. Treatment of both types of wastewater is in many cases very costly and difficult due to quality and quantity fluctuations in time as well as high concentrations of specific pollutants. In case of our investigation the TSS concentration in RWC was two times higher than in LL. The shere of...
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Straightening of ship hull structure made of 316L stainless steel - tensile test of water cooled materia
Open Research DataThe AISI 316L type steel belongs to the group of chromium-nickel stainless steels. They are determined according to European standards as X2CrNiMo17-12-2 and belong to the group of austenitic stainless steels. Steels of this group are used for elements working in seawater environments, for installations in the chemical, paper, and food, industries,...
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Combination of hydrodynamic cavitation and SR-AOPs for simultaneous degradation of BTEX in water
PublicationHydrodynamic cavitation (HC) is an emerging technology gaining interest in water treatment for use in elimination of a wide range of organic pollutants. The energy released during cavitation phenomenon has number of applications and, particularly, it can be utilized for activation of persulfate (PS) and peroxymonosulfate (PMS). In the present study, hybrid techniques: HC combined with persulfates – HC-PS and HC-PMS were tested...
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Critical analysis of laboratory measurements and monitoring system of water-pipe network corrosion-case study.
PublicationCase study of corrosion failure of urban water supply system caused by environmental factors was presented. Nowadays corrosion monitoring of water distribution systems is an object of major concern. There is possibility of application broad range of techniques like gravimetric and electrochemical. Both kinds of techniques can be applied in laboratory and field conditions. In many cases researches limit the case analysis to measurements...
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Free convection of water-Al2O3 nanofluid from horizontal porous coated tube
PublicationNanofluids are expected to enhance heat transfer in many thermal systems. Present efforts are concentrated on boiling heat transfer of nanofluids, although single phase convection is of key importance in various appliances such as car radiators or heating systems. This paper presents experimental results of heat transfer during free convection of water-Al3O3 nanofluid from horizontal tube covered with metallic porous coating. Contrary...
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Correction: Białowiec, A., et al. The Oxygen Transfer Capacity of Submerged Plant Elodea densa in Wastewater Constructed Wetlands. Water, 2019, 11, 575
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Detection of People Swimming in Water Reservoirs with the Use of Multimodal Imaging and Machine Learning
PublicationEvery year in many countries, there are fatal unintentional drownings in different water reservoirs like swimming pools, lakes, seas, or oceans. The existing threats of this type require creating a method that could automatically supervise such places to increase the safety of bathers. This work aimed to create methods and prototype solutions for detecting people bathing in water reservoirs using a multimodal imaging system and...
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Water Solubilization Using Nonionic Surfactants from Renewable Sources in Microemulsion Systems
PublicationIn this study the effect of temperature, NaCl andoils (hydrocarbons: C8-C16) on the formation and solubilizationcapacity of the systems of oil/monoacylglycerols(MAG):ethoxylated fatty alcohols (CEO20)/propylene glycol(PG)/water was investigated. The effects of the surfactantmixture on the phase behavior and the concentration ofwater or oil in the systems were studied at three temperatures(50, 55, 60 C) and with varied NaCl solutions...
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INFLUENCE OF SOLID PARTICLE CONTAMINATION ON THE WEAR PROCESS IN WATER LUBRICATED MARINE STRUT BEARINGS WITH NBR AND PTFE BUSHES
PublicationThis paper reports on a study of the influence of solid particle contamination on the wear process in water-lubricated slide bearings (steel-acrylonitrile-butadiene rubber (NBR) and steel- polytetrafluoroethylene (PTFE)). To compare the wear of the shaft journal and bushes (NBR and PTFE) when lubricated with fresh water and contaminated water, an experiment was carried out to identify key factors that influence the state of wear...
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Long-term Hindcast Simulation of Currents, Sea Level, Water Temperature and Salinity in the Baltic Sea
PublicationThis dataset contains the results of numerical modelling of currents, sea level, water temperature and salinity over a period of 50 years (1958–2007) in the Baltic Sea. A long-term hindcast simulation was performed using a three-dimensional hydrodynamic model (PM3D) based on the Princeton Ocean Model (POM). The spatial resolution was 3 nautical miles, i.e. about 5.5 km. Currents, water temperature, and salinity were recorded...
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Water uptake and energetics of the formation of barium zirconate based multicomponent oxides
PublicationA group of multi-component oxides based on BaZrO3 have been prepared using a solid-state reaction method and examined in terms of their water uptake and thermodynamics of formation. Depending on the type and amount of acceptor substitution, the synthesized compounds exhibit various proton defect concentrations, reaching up to 0.2 mol/mol for a compound containing 10 different elements in the B-sublattice, where 50% of them are...
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Kernel PCA in Application to Leakage Detection in Drinking Water Distribution System
PublicationMonitoring plays an important role in advanced control of complex dynamic systems. Precise information about system's behaviour, including faults detection, enables efficient control. Proposed method- Kernel Principal Component Analysis (KPCA), a representative of machine learning, skilfully takes full advantage of the well known PCA method and extends its application to nonlinear case. The paper explains the general idea of KPCA...
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Hydrophobic (deep) eutectic solvents (HDESs) as extractants for removal of pollutants from water and wastewater – A review
PublicationDeep eutectic solvents (DESs) are a new generation of solvents that attracted increasing attention in diverse applications. In last years, growing number of studies on hydrophobic (deep) eutectic solvents (HDESs) as an alternative extractants for various chemicals from aqueous environments have been reported. This article provides an overview on the usage of HDESs in liquid–liquid extraction (LLE) of different pollutants from water...
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Determination of causes of accelerated local corrosion of austenitic steels in water supply systems
PublicationThis paper concerns an inspection of a water supply system, made of AISI 304 steel, which showed signs of local corrosion at the weld. Such corrosion caused material perforation after very short periods of operation. It was revealed that steel was sensitised during the welding process. It was also proven that chromium micro-segregation occurred in the alloy leading to galvanic cell formation which initialised the process of pitting...
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An optimised placement of the hard quality sensors for a robust monitoring of the chlorine concentration in drinking water distribution systems
PublicationThe problem of an optimised placement of the hard quality sensors in drinking water distribution systemsunder several water demand scenarios for a robust monitoring of the chlorine concentration is formulatedin this paper. The optimality is understood as achieving a desired trade off between the sensors and theirmaintenance costs and the accuracy of estimation of the chlorine concentration. The contribution of thiswork is a comprehensive...
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Polychlorinated Biphenyls (PCBs) and Polycyclic Aromatic Hydrocarbons (PAHs): Sediments and Water Analysis
PublicationUnfavorable side effects of different forms of anthropogenic activities can be found anywhere in the world. One of the basic characteristics of pollutants entering marine and ocean waters is their spread and movement in the global ocean. A portion of the substances entering the marine environment is rapidly degraded by chemical processes occurring in the air, sediments, and water, thereby losing their toxic properties. The biggest...
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Exfoliated graphite with spinel oxide as an effective hybrid electrocatalyst for water splitting
PublicationThe aim of the conducted research was to develop hybrid nanostructures formed from MnCo2O4 and exfoliated graphite. Carbon added during the synthesis allowed for obtaining a well-distributed MnCo2O4 particle size with exposed active sites contributing to the increased electric conductivity. The influence of the weight ratios of carbon to a catalyst for hydrogen and oxygen evolution reactions was investigated. The new bifunctional...
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Low-energy positron collisions with water: elastic and rotationally inelastic scattering
PublicationDifferential, integral and momentum transfer cross sections for the vibrationally elastic and rotationally inelastic scattering of positrons from water at low collision energy (E ≤ 10 eV) are reported. Several models within the R-matrix method are used to compute the body-fixed T-matrices, while the scattering calculations are performed within the fixed-nuclei approximation corrected with the standard Born-closure formula. These...
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Postępy Akustyki // Advances in Acoustics rozdział: Doskonalenie metod detekcji i śledzenia ruchu obiektów podwodnych pasywnym sonarem dalekiego zasięgu z holowaną liniową anteną
PublicationDalekosiężne pasywne sonary z długimi holowanymi antenami są obecnie najlepszymi systemami do wykrywania obecności i określania namiarów na współczesne, ciche okręty podwodne. Dlatego są stosowane zarówno na dużych okrętach nawodnych jak i podwodnych mimo niewygód przy ich rozwijaniu, holowaniu i zwijaniu a także mimo zawiłości oraz niejednoznaczności wskazań (tylko namiary na cel - bez rozróżnienia lewej i prawej burty oraz brak...
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Predictive Capacity of Rainfall Data to Estimate the Water Needs of Fruit Plants in Water Deficit Areas
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THE IMPLICATIONS OF ECONOMIC DEVELOPMENT, CLIMATE CHANGE AND EUROPEAN WATER POLICY ON SURFACE WATER QUALITY THREATS
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The usefulness of ascorbic acid degradation to analyze the effectiveness of water filtration in household water filter jugs
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Theoretical study of the structure, energetics and vibrational frequencies of water-acetone and water-2-butanone complexes
PublicationKompleksy acetonu i 2-butanonu z 0-2 cząsteczkami wody połączonymi wiązaniem wodorowym z tlenem karbonylowym zbadano z wykorzystaniem teorii funkcjonału gęstości (DFT) na poziomie B3LYP/6-311++G(d,p). Obliczenia w fazie gazowej uzupełniono o optymalizacje w otoczeniu rozpuszczalnika, symulowanego za pomocą modelu polaryzowalnego kontinuum (PCM). Częstości drgań oscylacyjnych otrzymane na podstawie zależności empirycznej sa zgodne...
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Comparison of the coordination geometries of Zn(II) and Cd(II) ions in complexes with water, methanol and bulky aryloxysilanethiolate ligands
PublicationZinc and cadmium complexes containing silanethiolate anions and methanol or water were synthesized and characterized by X-ray diffraction, FT-IR and NMR spectroscopy, and DFT calculations. Contrary to zinc, the cadmium ion utilizes very weak donors to complete its coordination sphere; it forms contacts to phenyl rings of the silanethiolate ligand. Two zinc analogs of the general formula [Zn{SSi(OAr)3}2(L)2] where L = CH3OH (2)...
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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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Monitoring Salt Water Intrusion During Construction of a Road Tunnel under the Martwa Wisła River in Gdańsk
PublicationThe paper presents results of groundwater monitoring carried out during the construction of a road tunnel under the Martwa Wisła river in Gdańsk, Poland. Martwa Wisła is one of the branches of Wisła (Vistula) river, heavily influenced by storm surges and saline water inflow from the Bay of Gdańsk. Increased values of chloride concentration were observed on both sides of the river, in particular on the western side, which was caused...
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Mathematical Modeling of the Impact Range of Sewage Discharge on the Vistula Water Quality in the Region of Włocławek
PublicationThe paper presents results of analysis of the industrial sewage discharge influence at km 688 + 250 of the Vistula River on water quality. During the analysis, two-dimensional models of flow, impurities and temperature transport were used. Hydrological conditions of the analyzed section of the river, characteristic flows and bathymetry of the riverbed in the first instance were defined. Calculations of velocity distribution at...
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Two Time-Scale Hierarchical Control of Integrated Quantity and Quality in Drinking Water Distribution Systems
PublicationThe paper considers a feedback optimising control of drinking water distribution systems (DWDS). Although the optimised pump and valves scheduling and disinfectant injection control attracted considerable attention over last two decades most of the contributions were limited to an open-loop optimisation repetitively performed during the DWDS operation. Also, while a strong interaction between the water quantity and quality exists...
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Fuzzy Sets in the GIS Environment in the Location of Objects on the Surface of Water Bodies
PublicationThe issue presented here focuses on concerns about the localization of the object on water surface. The article shows how to facilitate localization process by applying mathematical solutions characterized by simplicity, rapid action and delivering credible results. The paper shows the results of background experiments, which enabled to collect technical parameters needed for conducting simulation testing. The research has been...