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wszystkich: 443
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Wyniki wyszukiwania dla: underground pipe
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Determination of p-y curves for offshore piles based on in-situ soil investigations
PublikacjaOffshore piles are subjected to complex loads with considerable lateral component. The pile-soil response to lateral loads can be described with the p-y method. For a given depth the load–deflection relationship is built to simulate the surrounding soil stiffness. This state-of-art paper presents a brief discussion of determination methods for the p-y curves using a standard approach based on the soil parameters derived from laboratory...
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CFGFRPT Piles with a Circular Cross-Section and their Application in Offshore Structures
PublikacjaThe possibilities of using concrete piles in a polymer composite reinforced with glass fibres in offshore facilities were shown. Laboratory tests of CFGFRPT type piles compressed axially and in eccentric compression for the analysis of CFGFRPT piles were used. Methods of analysis of dynamic systems for mathematical modelling of the displacement of the hammer in the pile driving process were applied. The possibilities of combining...
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Badania połączeń spawanych rurociągu wody pitnej we Włocławku, ang. Welding joints tests in drinking water pipeline.
PublikacjaCelem badań opisanych w pracy było określenie przyczyn korozji powstałej w strefie wpływu ciepła (SWC) w obwodowych połączeniach spawanych w rurociągu wody pitnej. Materiałem, z którego wykonano rurociąg to stal 304/304L. W obszarze złącza spawanego stwierdzono wżery inicjowane od niezgodności geometrycznych, gdzie mogły gromadzić się osady zwiększające udział chlorków bezpośrednio przy powierzchni rury, promujące tym procesy korozyjne....
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Evaluation of mercury content in combustible tobacco products by employing cold vapor atomic absorption spectroscopy and considering the moisture content: a comprehensive study
PublikacjaPlants are mainly made up of water, which constitutes between 80 and 90% of their weight. Moisture factor comes across as one of the most important in tobacco products. Rapid determination of moisture content in tobacco products comes at neces- sity in any tobacco management plants (before and after production). Therefore, the concern has been raised in this study to evaluate the moisture content in four kinds of combustible tobacco...
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Atmospheric deposition in coniferous and deciduous tree stands in Poland
PublikacjaThe objective of this study was to assess the transformation of precipitation in terms of quantity and chemical composition following contact with the crown layer in tree stands with varied species composition, to investigate the effect of four predominant forest-forming species (pine, spruce, beech, and oak) on the amount and composition of precipitation reaching forest soils, and to determine the sources of pollution in atmospheric...
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Metoda prognozowania mocy skrawania przy przecinaniu piłami polskiego drewna sosnowego z uwzględnieniem wiązkości materiału obrabianego
PublikacjaW pracy zostały przedstawione wartości właściwości materiałowych tj.: wiązkość R oraz naprężenia tnące w strefie skrawania τy, dla drewna sosnowego (Pinus sylvestris L.). Badane próbki drewna pochodziły z czterech Krain Przyrodniczo - Leśnych Polski: Bałtyckiej Krainy Przyrodniczo - Leśnej (kraina A), Karpackiej Krainy Przyrodniczo - Leśnej (kraina B), Małopolskiej Krainy Przyrodniczo - Leśnej (kraina C) oraz Wielkopolsko - Pomorskiej...
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Pylon foundation of a cable stayed bridge at the motorway ring road of Wrocław
PublikacjaThe largest bridge of the motorway ring road of Wroclaw is a cable stayed bridge over the Odra river near Rędzin. Due to hydrogeological conditions of the ground it was not convenient to use standard bored piles of high length. Instead shorter piles were applied with additional improvement by cement injections at the pile toes. This decision was possible by extending ground investigation program and application of numerical modeling...
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NUMERICAL MODELLING AND EXPERIMENTATION OF HISTORICAL CARPENTRY CORNER LOG JOINTS
PublikacjaThe main purpose of this research is to determine the stress distributions on the contact surfaces between the logs of the historical carpentry corner joints. The additional purpose is to compare the stress distribution for four different boundary conditions in the case of dry and wet pine wood. The paper presents the results of numerical analysis of the shortcorner dovetail connection and the saddle notch corner joint, which are...
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Fracture mechanics model of cutting power versus widespread regression equations while wood sawing with circular saw blades
PublikacjaA comparison of the theoretical cutting power consumption results forecasted with the model (FM_CM model) which include work of separation (fracture toughness) in addition to plasticity and friction, and two widespread regression equations while wood sawing with circular saw blades has been described. in and cutting power consumption forecasted. In computations of the cutting power consumption during rip sawing of Scots pine wood...
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Empirical verification in industrial conditions of fracture mechanics models of cutting power prediction
PublikacjaA comparison of experimental results obtained in the industrial conditions at a sawmill located in the Baltic Natural Forest Region (PL) and theoretical cutting power consumption forecasted with the models which include work of separation (fracture toughness) in addition to plasticity and friction has been described. In computations of cutting power consumption during rip sawing of Scots pine wood (Pinus sylvestris L.) values of...
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An assessment of teeth quality of the mini gang saw blade
PublikacjaIn this work, the assessment of the effect of the operating time (90 min.) of the mini gang saw blades during sawing Scotch pine (Pinus sylvestris L.) samples upon changes of the saw blade teeth sharpness (bluntness), which was defined as an effective radius of the nose ρ , has been described. The research activities have been carried out on the Nikon Ti-S optical microscope equipped with the Nikon DS-30W camera allowing high-speed...
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Simplified Numerical Model for Transient Flow of Slurries at Low Concentration
PublikacjaRapid transients are particularly dangerous in industrial hydro-transport systems, where solid-liquid mixtures are transported via long pressure pipelines. A mathematical description of such flow is difficult due to the complexity of phenomena and difficulties in determining parameters. The main aim of the study was to examine the influence of the simplified mixture density and wave celerity description on satisfactory reproduction...
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Thermal and Hydrodynamic Phenomena in the Stagnation Zone — Impact of the Inlet Turbulence Characteristics on the Numerical Analyses
PublikacjaOne of the methods of heat transfer enhancement is utilization of the turbulent impinging jets, which were recently applied, for example, in the heat exchangers. Their positive impact on the heat transfer performance was proven, but many questions related to the origin of this impact are still unanswered. In general, the wall-jet interaction and the near-wall turbulence are supposed to be its main reason, but their accurate numerical...
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Thermodynamic and economic analysis of nuclear power unit operating in partial cogeneration mode to produce electricity and district heat
PublikacjaThis 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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An Experimental Investigation of Pressure Wave Celerity During the Transient Slurry Flow
PublikacjaTransportation of slurries in pressure pipelines is an example of a complex flow due to specific parameters of transported medium. For practitioners, the economy of designing and maintenance is usually the most important factor. For this reason, most of hydrotransport installations are fairly simple; however, they become more vulnerable to negative effects of the transient flow which can occur in pressure pipelines. As the consequence,...
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Porous structures in aspects of transpirating cooling of oxycombustion chamber walls
PublikacjaA wet oxycombustion chamber, which must be effectively cooled due to high temperature evolved during the oxy-combustion process, by using the phenomena of Reynolds thermal transpiration and Navier slip velocity. Closures needed to execute mass flow rate in a microchannel, which should be treated as a single porous structure in the walls of the combustion chamber, have been obtained by applying a local 3D approach. The Navier-Stokes...
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Preliminary estimation of groundwater recharge on Brda river outwash plain
PublikacjaEstimation of groundwater recharge is one of the most challenging subjects in hydrogeology. It is a critical factor influencing the pollution migration, assessment of aquifer vulnerability to contamination, small-scale groundwater budget calculation, modeling of nutrient cycling and detailed flow path calculations. In Poland an infiltration rate method is widely used, which depends on a system of rate coefficients referring to...
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Hydrogen production from wood waste by mean of dark fermentation
PublikacjaThe utilization of wood wastes in clean and green chemistry method like by mean of dark fermentation, is a highly desired solution of waste management. In the article model for the estimation hydrogen potential of wood waste is given. The model has been used to calculate the potential theoretical hydrogen mass that can be produced from wood wastes in Pomerania and Silesia: pine, spruce, fir, beech and oak. In the introduction,...
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The Use of Photographs in the Teaching/Learning of Descriptive Geometry
PublikacjaThe article presents the concept of enriching the Descriptive Geometry course with photographs and several simplified real-life engineering tasks. The photographic images used for the exercises are tightly linked to engineering structures, the given specialization and the surrounding world. The photo image as a record of central projection of a real space can be useful for presentation and analysis of the properties of perspective....
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Nonlinear fuzzy control of the dissolved oxygen in activated sludge processes
PublikacjaWastewater treatment plant is generally a complex, multivariable, time varying and nonlinear large scale industrial system. Moreover, interactions between the components are very strong. The dissolved oxygen tracking problem is one of the most complex and fundamental issues of biological processes. Air for the aerated tanks is supplied by aeration system (blowers, pipes, diffusers). It is a complex dynamic system. The new control...
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The chaperone-usher pathway of bacterial adhesin biogenesis - from molecular mechanism to strategies of anti-bacterial prevention and modern vaccine design
PublikacjaSystem chaperone-usher (białko opiekuńcze-białko kanałotwórcze) warunkuje biogenezę powierzchniowych struktur adhezyjnych, odpowiedzialnych za wirulencję wielu bakterii gram-ujemnych. Powyższy mechanizm został zbadany na poziomie strukturalnym w przypadku różnych gatunków bakterii patogennych. Celem powyższej pracy było przedstawienie molekularnego mechanizmu biogenezy struktur adhezyjnych na bazie systemu chaperone-usher. Otrzymane...
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Cartometric: semantic ontology evaluation with cartographic methods
PublikacjaW ostatnich latach, głównie dzięki rozwojowi inicjatywy Sieci Semantycznej (ang. Semantic Web), staliśmy się świadkami powstawania coraz większej liczby gwałtownie ewoluujących ontologii. W takiej sytuacji zarówno użytkownicy Sieci, jak i komputerowe agenty potrzebują metody oceny właściwości ontologii, w szczególności takiej, która uwzględni jej cechy semantyczne, czyli kształt przestrzeni dozwolonych modeli. Niniejsza praca prezentuje...
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CartoMetric: Ocena semantycznych właściwości ontologii za pomocą metody kartograficznej
PublikacjaW ostatnich latach, głównie dzięki rozwojowi inicjatywy Sieci Semantycznej (ang. Semantic Web), staliśmy się świadkami powstawania coraz większej liczby gwałtownie ewoluujących ontologii. W takiej sytuacji zarówno użytkownicy Sieci, jak i komputerowe agenty potrzebują metody oceny właściwości ontologii, w szczególności takiej, która uwzględni jej cechy semantyczne, czyli kształt przestrzeni dozwolonych modeli. Niniejsza praca prezentuje...
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CUTTING POWER FORECASTING WHILE WOOD SAWING: FRACTURE MECHANICS APPROACH AND AXELSSON’S MODEL COMPARISON
PublikacjaIn the classical approach, energetic effects (cutting forces and cutting power) of wood sawing process are generally calculated on the basis of the specific cutting resistance, which is in the case of wood cutting the function of more or less important factors. On the other hand, cutting forces (power) could be considered from a point of view of modern fracture mechanics. Another way is to forecast cutting power consumption on...
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Non-destructive Diagnostics of the Floor in the Gdańsk Crane Using Ground Penetrating Radar = Diagnostyka nieniszcząca posadzki w gdańskim Żurawiu z zastosowaniem metody georadarowej
PublikacjaThis paper presents the results of a ground penetrating radar (GPR) survey carried out at the Crane in Gdańsk. The measurements were conducted on the floor of the southern and northern towers. The aim of the experiment is to assess the possibility of detecting anomalies beneath the floor. The surveys were carried out in a non-destructive manner, using a georadar unit with 2 GHz and 400/900 MHz antennas. This paper compares the...
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Advanced sensitivity analysis of the impact of the temporal distribution and intensity of rainfall on hydrograph parameters in urban catchments
PublikacjaKnowledge of the variability of the hydrograph of outflow from urban catchments is highly important for measurements and evaluation of the operation of sewer networks. Currently, hydrodynamic models are most frequently used for hydrograph modeling. Since a large number of their parameters have to be identified, there may be problems at the calibration stage. Hence, sensitivity analysis is used to limit the number of parameters....
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Microseismic Monitoring of Hydraulic Fracturing - Data Interpretation Methodology With an Example from Pomerania
PublikacjaMicroseismic monitoring is a method for localizing fractures induced by hydraulic fracturing in search for shell gas. The data is collected from an array of geophones deployed on the surface or underground. Ground vibrations are recorded and analysed for fracture location, magnitude and breakage mechanism. For successful microseismic monitoring one need a velocity model of underlying formations. The model is further tuned with...
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Analysing By-Products Interaction as an Industry Resource of Circular Economy in Ukraine and the World
PublikacjaThe paper analyses existing and current scientific developments and literature sources, which show the advantages and disadvantages of many different influences of waste in Ukraine and other countries of Europe and the world. As a research result, stable connections have been established between the factors and criteria in assessing the by-product interaction as an industry resource. In our research, we used programs R.Studio and...
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Two-phase optimizing approach to design assessments of long distance heat transportation for CHP systems
PublikacjaCogeneration or Combined Heat and Power (CHP) for power plants is a method of putting to use waste heat which would be otherwise released to the environment. This allows the increase in thermodynamic efficiency of the plant and can be a source of environmental friendly heat for District Heating (DH). In the paper CHP for Nuclear Power Plant (NPP) is analyzed with the focus on heat transportation. A method for effectivity and feasibility...
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Influence of the low ambient temperature on the start-up process of hydraulic pumps
PublikacjaStarting hydraulic pumps in low ambient temperatures may cause: decreased hydraulic-mechanical efficiency, larger vibration of hydraulic installation, faster wear and more frequent damage to the elements of pumps, change of material properties of elements, increase of pressure drop. As a result of pressure drop in the suction pipe, large underpressure may be experienced, causing incomplete filling of pump working chambers with...
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Zarządzanie wiedzą ontologiczną w środowisku semantycznego internetu
PublikacjaW rozdziale zaprezentowano wyniki grupy badawczej Knowledge Management Group at Gdańsk University of Technology (KMG@GUT) w zakresie nowych metod reprezentacji i przetwarzania wiedzy sformułowanej w formie ontologii. Metody te wpisują się w aktualne kierunki rozwojowe inicjatywy Semantic Web: wykorzystują do zapisu ontologii logikę opisową (a więc są zgodne ze standardem OWL-DL), biorą pod uwagę rozproszenie wiedzy pomiędzy różne...
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Influence of steam drying process on wood mechanical properties
PublikacjaResults of influence of gas-steam mixture drying process on mechanical properties of material are presented. Wood species, namely oak (Quercus L.), beech (Fagus L.), pine (Pinus L.) and spruce (Picea K.) from the northern part of Pomerania region in Poland, were subject of air-steam mixture drying process in a laboratory kiln especially arranged for that reason. Measurements of the global coefficient of elasticity and bending strength...
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Comparative tests of the wall thickness effect of a glass-reinforced thermosetting plastic coating with a non-circular cross section in a soil-coating object for economic aspect
PublikacjaCulvert structures made of plastics are employed extensively in the construction of new facilities as well as the renovation of existing ones. Due to the high costs of materials required for the manufacturing of these goods, the objective of this research is focused to lessen the thickness of the walls, which may, on the other hand, result in a reduction in the stiffness of the system. In the course of the testing, the structure...
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Ocena stanu technicznego rurociągu przesyłowego zawiesiny popiołów w Elektrowni Ostrołęka B
PublikacjaPrzedmiotem pracy był rurociąg przesyłowy zawiesiny popiołów przesyłanych z Elektrowni Ostrołęka B. Celem pracy było potwierdzenie przynależności próbek yvyciętych z rurociągu do określonego gatunku stali i ocena stanu materiału po eksploatacji. Dla zrealizowania tego celu wykonano: - analizę składu chemicznego materiału pobranego ze stalowych rur, - mikroanalizę warstw wierzchnich na powierzchni wewnętrznej i zewnętrznej, -...
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Analysis of the state of preservation the historic arcaded houses in Vistula Delta listed in the National Inventory of Historical Monuments
PublikacjaHistoric arcaded houses are part of the material heritage of the Vistula Delta. Unfortunately, their number is decreasing year by year. The article is the result of a query of available sources and field research carried out by the author in 2015-2020. The paper presents the current state of preservation the historic arcaded houses in Vistula Delta listed in the National Inventory of Historical Monuments. Criteria for the selection...
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SDF classifier revisited
PublikacjaArtykuł dotyczy problemów związanych z konstruowaniem klasyfikatorów wykorzystujących tzw. dyskryminacyjną funkcję samopodobieństwa (ang. Similarity Discriminant Function - SDF), w których tradycyjna, wektorowa reprezentacja obrazu została zastąpiona przez dane o strukturze macierzowej. Zaprezentowano możliwości modyfikowania macierzowych struktur danych i zaproponowano nowe warianty kryterium SDF. Przedstawione algorytmy zostały...
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Impact of new, navigable canal through the Vistula spit on the hydrologic balance of the Vistula lagoon (Baltic Sea)
PublikacjaThe object of research - the Vistula Lagoon is one of the two lagoons on the Polish coast, which is of great importance not only from an economic point of view, but also an environmental one. The purpose of the paper is to provide calculations on the current water balance for the Vistula Lagoon, before and after construction of a canal through the Vistula Spit. This is important because the construction of a new connection between...
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Two-Level Multivariable Control System of Dissolved Oxygen Tracking and Aeration System for Activated Sludge Processes
PublikacjaThe problem of tracking dissolved oxygen is one of the most complex and fundamental issues related to biological processes. The dissolved oxygen level in aerobic tanks has significant influence on behaviour and activity of microorganism inhabiting the plant. Aerated tanks are supplied with air from an aeration system (blowers, pipes, throttling valves, diffusers). It is a complex dynamic system governed by nonlinear hybrid dynamics....
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A Model-Based Improved Control of Dissolved Oxygen Concentration in Sequencing Wastewater Batch Reactor
PublikacjaBiochemical processes at wastewater treatment plant are complex, nonlinear, time varying and multivariable. Moreover, relationships between processes are very strong. One of the most important issues is exerting proper control over dissolved oxygen levels during nitrification phase. This parameter has a very large impact on activity of microorganisms in activated sludge and on quality of pollution removal processes. Oxygen is supplied...
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Selected aspects of the surface quality of the wooden elements after planing
PublikacjaThe quality of the surface of wooden elements, that have been planed, has got a crucial meaning in the whole production process flow, since the obtained effects affect the quality of wooden surface after painting. The emergence of defects in most cases causes need to qualify workpiece as a scrap part or additional work activity must be done. In the paper selected results of the investigation of the effect of the cutting tool wear...
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Pharmaceuticals and other contaminants of emerging concern in Admiralty Bay as a result of untreated wastewater discharge: Status and possible environmental consequences
PublikacjaConsidering how the impact of human activity in Antarctica is growing, the aim of this study was to conduct the first assessment of pharmaceuticals and personal care products (PPCPs), other emerging contaminants (ECs), and antibiotic resistance genes present in the western shore of the Admiralty Bay region of King George Island. In total, more than 170 substances were evaluated to assess the potential environmental risks they pose...
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MultiRegional PCA for leakage detection and localisation in DWDS - approach
PublikacjaMonitoring is one of the most important parts in advanced control of complex dynamic systems. Information about systems behavior, including failures indicating, enables for efficient control. The chapter describes an approach to detection and localisation of pipe leakage in Drinking Water Distribution Systems (DWDS) representing complex and distributed dynamic system of large scale. Proposed MultiRegional Principal Component Analysis...
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Performance of the domestic micro ORC equipped with the shell-and-tube condenser with minichannels
PublikacjaIn this paper, the original compact shell-and-tube heat exchanger with circular minichannels of in-house design and manufacturing is presented as the condenser for the domestic micro heat and power plant investigations as well as other future technical applications. The heat exchanger is equipped with turbulizing baffles inside the shell. The shell itself is made of a tubular sleeve having an inner diameter of 0.067 m and the length...
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Granulometric characterization of Arctic driftwood sawdust from frame sawing process
PublikacjaArctic driftwood can be used as an alternative source of wood as construction timber and furniture material, especially in Iceland and Greenland. The use of Arctic driftwood can help in the fight against climate change, by developing land reforestation processes and reducing the volume harvested wood from forests and sustainability of harvesting processes. In this paper the results of an analysis of the effect of long-term residence...
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Technological solutions to landfill management: Towards recovery of biomethane and carbon neutrality
PublikacjaInadequate landfill management poses risks to the environment and human health, necessitating action. Poorly designed and operated landfills release harmful gases, contaminate water, and deplete resources. Aligning landfill management with the Sustainable Development Goals (SDGs) reveals its crucial role in achieving various targets. Urgent transformation of landfill practices is necessary to address challenges like climate change,...
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Focused crawler for trustworthy healthcare information search
PublikacjaArtykuł zawiera opis prac wykonanych w projekcie 6 Programu Ramowego Unii Europejskiej: Personalised Information Platform for life and health Services (PIPS). Głównym celem projektu jest zapewnienie obywatelowi Unii kompleksowego wspomagania w zakresie zagadnień ochrony zdrowia oraz odżywiania. Do realizacji tego celu konieczne jest pozyskanie i dostarczenie obywatelowi wiarygodnej, prawdziwej i aktualnej informacji z tych dziedzin....
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Nonlinear Fuzzy Control System for Dissolved Oxygen with Aeration System in Sequencing Batch Reactor
PublikacjaBiological processes at a wastewater treatment plant are complex, multivariable, time varying and nonlinear. Moreover, interactions between the components are very strong. Control of dissolved oxygen is one of most important task at the plant. The level of dissolved oxygen in aerobic tanks has significant influence on behaviour and activity of microorganisms at the plant. Air for aerated tanks is supplied by the aeration system...
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Integrated Application of GPR and Ultrasonic Testing in the Diagnostics of a Historical Floor
PublikacjaThe paper presents the results of integrated ground penetrating radar (GPR) and ultrasonic testing (UT) measurements conducted on a historical floor in St. Nicholas’ Church, Gdańsk, Poland. The described inspection was the first stage of the technical state assessment of the building. The aim of the study was the detection of underfloor air gaps, which were observed in a few trial pits. The condition of the ground under the floor...
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Theoretical and Actual Feed Per Tooth During Wood Sawing on an Optimizing Cross-Cut Saw
PublikacjaThe work presents the geometries of circular saw teeth, whose task is to divide the cross-cut of the cutting layer. For efficient machining on a cross-cut saw with high feed speed values (about 1 ms−1) maximal theoretical feeds per tooth are determined. These values were compared with the actual values determined during transverse cutting of pine wood on a special test stands in industrial conditions. In the experiment the rotational...
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Molywood: streamlining the design and rendering of molecular movies
PublikacjaMotivation High-quality dynamic visuals are needed at all levels of science communication, from the conference hall to the classroom. As scientific journals embrace new article formats, many key concepts – particularly in structural biology – are also more easily conveyed as videos than still frames. Notwithstanding, the design and rendering of a complex molecular movie remain an arduous task. Here, we introduce Molywood, a robust...