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An attempt to mechanistically explain the viscoelastic behavior of transparent epoxy/starch-modified ZnO nanocomposite coatings
PublikacjaThe effects of bare and starch-modified ZnO (ZnO-St) nanoparticles on viscoelastic and mechanical properties are studied by dynamic mechanical and tensile analyses. Transparent epoxy-based nanocomposite films are prepared by incorporating bare or starch-modified ZnO particles into the epoxy matrix. The results demonstrated that ZnO particles hindered the curing reactions and hence the final properties of the cured epoxy. As a result,...
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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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Silica Gel Impregnated by Deep Eutectic Solvents for Adsorptive Removal of BTEX from Gas Streams
PublikacjaThe paper presents the preparation of new adsorbents based on silica gel (SiO2) impregnated with deep eutectic solvents (DESs) to increase benzene, toluene, ethylbenzene, and p-xylene (BTEX) adsorption efficiency from gas streams. The DESs were synthesized by means of choline chloride, tetrapropylammonium bromide, levulinic acid, lactic acid, and phenol. The physico-chemical properties of new sorbent materials, including surface...
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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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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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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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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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More Just Measure of Fairness for Sharing Network Resources
PublikacjaA more just measure of resource distribution in computer networks is proposed. Classic functions evaluate fairness only “on average”. The proposed new fairness score function ensures that no node is left without resources while on average everything looks good. It is compared with well-known and widely adopted function proposed by Jain, Chiu and Hawe and another one recently proposed fairness function by Chen and Zhang. The function...
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Functionalized azobenzocrown ethers as sensor materials—The synthesis and ion binding properties
PublikacjaNew 13- and 16-membered azobenzocrown ethers with aromatic amino, amide, ether–ester or ether–amide residue in para position to an azo moiety were obtained. Acid–base properties and ion binding ability of the colored compounds were studied by spectroscopic methods: UV–vis, fluorimetry and 1H NMR spectroscopy. Selected azobenzocrowns were tested as ionophores in ion-selective membrane electrodes (ISEs) – classic and miniature all...
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Investigation of the aerodynamics of an innovative verticalaxis wind turbine
PublikacjaThis paper presents a preliminary three dimensional analysis of the transient aerodynamic phenomena occurring in the innovative modification of classic Savonius wind turbine. An attempt to explain the increased efficiency of the innovative design in comparison with the traditional solution is undertaken. Several vorticity measures such as enstrophy, absolute helicity and the integral of the velocity gradient tensor second invariant...
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Experimental Comparison of Straight Lines and Polynomial Interpolation Modeling Methods in Ship Evolutionary Trajectory Planning Problem
PublikacjaPaper presents the application of evolutionary algorithms and polynomial interpolation in ship evolutionary trajectory planning method and its comparison to classic approach, where trajectory is modeled by straight lines. Evolutionary algorithms are group of methods that allows\ to find a collision free trajectory in real time, while polynomial interpolation allows to model smooth trajectory, which keeps continuity of velocity...
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Valence and ionic lowest-lying electronic states of small esters studied by high resolution vacuum ultraviolet photoabsorption, photoelectron spectroscopy and ab initio calculations
PublikacjaEsters are an important class of oxygenated volatile organic compounds used in food flavorings, perfumes and other cosmetic products. They are present in fruits and pheromones and are emitted to the atmosphere naturally. Esters are also formed in the atmosphere as a product of the oxidation of ethers. Some of them form poly-molecule chains and are used in plastics. Phosphoesters form DNA backbone, while nitroesters are known for...
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DESIGN AND EXECUTION ERRORS AS A CAUSE OF DAMAGE TO ANTI- ELECTROSTATIC FLOORING
PublikacjaApart from technological lines, industrial floors are a key element in the scope of maintaining the continuity of work of both production plants and logistics centers. The constantly developing industry of industrial flooring includes both classic design and technological flooring solutions, as well as specialist solutions used in facilities where technological processes or storage require system protection against static electricity....
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Application of the Bodner-Partom constitutive equations for modelling of the technical fabric Valmex used for the hanging roof of the Forest Opera in Sopot
PublikacjaThe study of an inelastic properties of the technical fabric Valmex used for 20 years as the roof structure of the Forest Opera in Sopot (Poland) is presented. The uniaxial tensile laboratory tests with constant strain rate have been conducted and analysed. Parameters of the Bodner-Partom constitutive model have been identified and verified by numerical simulations. Two approaches of the parameters identification have been proposed:...
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Application possibilities of LBN for civil engineering issues
PublikacjaBayesian Networks (BN) are efficient to represent knowledge and for the reasoning in uncertainty. However the classic BN requires manual definition of the network structure by an expert, who also defines the values entered into the conditional probability tables. In practice, it can be time-consuming, hence the article proposes the use of Learning Bayesian Networks (LBN). The aim of the study is not only to present LBN, which can...
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Peer assessment as a method for measuring harmful internet use
PublikacjaHarmful Internet use (HIU) describes unintended use of the Internet. It could be both self-harm and harming others. Our research goal is to develop a more accurate method for measuring HIU by this novel peer assessment. As such, it may become, with our call for more research, a paradigm shift supplementing every rating scale or other type of Internet use assessment. In addition to classic statistical analysis, structural equations...
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Subspace Algorithms for Face Verification
PublikacjaW rzeczywistych zastosowaniach problem weryfikacji wydaje się ważniejszy od klasyfikacji. Na ogół dysponujemy jedynie niewielkim zbiorem obrazów uczących reprezentujących daną osobę, a naszym zadaniem jest podjęcie decyzji odnośnie tego, czy nowo pozyskana fotografia jest do nich wystarczająco podobna - bez użycia oddzielnego zbioru przykładów negatywnych. W takim przypadku uzasadnione wydaje się zastosowanie metody podprzestrzeni,...
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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...
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Prediction of the Mechanical Properties of P91 Steel by Means of Magneto-acoustic Emission and Acoustic Birefringence
PublikacjaThe paper describes an application of nondestructive volumetric magnetic and ultrasonic techniques for evaluation of the selected mechanical parameter variations of P91 steel having direct influence on its suitability for further use in critical components used in power plants. Two different types of deformation processes were carried out. First, a series of the P91 steel specimens was subjected to creep and second, one to plastic...
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Corrosion and Cavitation Resistances of Low Alloy Steel After Frictional-Mechanical Treatment
PublikacjaPaper presents the results of the studies of wear, corrosion and cavitation resistances of the S355J2 low alloy medium carbon steel subjected to surface modification by friction-mechanical treatment, as tested in sea water simulated solution. To evaluate the effect of the surface treatment, the comparative studies of the corrosive properties of the steel before and after treatment have been considered. The treatment due to a severe...
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Design of a Cellular Dual-Band Sticker Antenna for Thickness-Independent 3D-Printed Substrates
PublikacjaAdditive manufacturing technology provides high flexibility in designing custom enclosures for prototype devices such as nodes of distributed sensor networks. Although integration of components is desired from the perspective of sensor mobility, it might negatively affect the performance of radio-connectivity due to couplings between the antenna and system peripherals, as well as other unaccounted effects of the 3D printed enclosure....
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Prediction of coking dynamics for wet coal charge
PublikacjaA one-dimensional transient mathematical model describing thermal and flow phenomena during coal coking in an oven chamber was studied in the paper. It also accounts for heat conduction in the ceramic oven wall when assuming a constant temperature at the heating channel side. The model was solved numerically using partly implicit methods for gas flow and heat transfer problems. The histories of temperature, gas evolution and internal...
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Mitochondrial DNA copy number and trimethylamine levels in the blood: New insights on cardiovascular disease biomarkers
PublikacjaAmong cardiovascular disease (CVD) biomarkers, the mitochondrial DNA copy number (mtDNAcn) is a promising candidate. A growing attention has been also dedicated to trimethylamine-N-oxide (TMAO), an oxidative derivative of the gut metabolite trimethylamine (TMA). With the aim to identify biomarkers predictive of CVD, we investigated TMA, TMAO, and mtDNAcn in a population of 389 coronary artery disease...
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Verification of the new viscoelastic method of thermal stress calculation in asphalt layers of pavements
PublikacjaThe new viscoelastic method of thermal stress calculations in asphalt layers has been developed and published recently by the author. This paper presents verification of this method. The verification is based on the comparison of the results of calculations with results of testing of thermal stresses in Thermal Stress Restrained Specimen Test. The calculations of thermal stresses according to the new method were based on rheological...
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Cross-sections for electron-scattering from 2-methyl-1-buten-3-yne, C 5 H 6 , molecules
PublikacjatCross-sections for electron collisions with the 2-methyl-1-buten-3-yne [H2C C(CH3)C CH] moleculewere measured and calculated. Absolute grand-total electron-scattering cross-section (TCS) was takenat impact energies from 0.6 to 300 eV in the linear electron-transmission experiment. The TCS energydependence for the electron–C5H6collision has two prominent enhancements separated with a deepminimum located near 1.8 eV. In addition,...
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Influence of artificial thermal ageing on polyester-reinforced and polyvinyl chloride coated AF9032 technical fabric
PublikacjaThe presented work deals with the thermal ageing evaluation for polyester-reinforced and polyvinyl chloride coated fabrics. The architectural fabric AF9032 was exposed to artificial thermal ageing by subjecting the material samples to temperature levels of 80℃ and 90℃ for up to 12 weeks. The mechanical properties of the aged fabric have been separately described by the identified linear piecewise model (with assumption of the elastic...
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Material Parameters Identification of Historic Lighthouse Based on Operational Modal Analysis
PublikacjaIn the present paper, the identification of the material parameters of a masonry lighthouse is discussed. A fully non-invasive method was selected, in which the material properties were determined via numerical model validation applied to the first pair of natural frequencies and their related mode shapes, determined experimentally. The exact structural model was built by means of the finite element method. To obtain experimental...
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On nonlinear dilatational strain gradient elasticity
PublikacjaWe call nonlinear dilatational strain gradient elasticity the theory in which the specific class of dilatational second gradient continua is considered: those whose deformation energy depends, in an objective way, on the gradient of placement and on the gradient of the determinant of the gradient of placement. It is an interesting particular case of complete Toupin–Mindlin nonlinear strain gradient elasticity: indeed, in it, the...
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Equalization of pad loads in large tilting pad thtust bearing
PublikacjaW pracy przedstawiono przebieg projektowania zmodernizowanego łożyska wzdłużnego hydrogeneratora. Na podstawie eksploatacyjnych danych o zróżnicowaniu temperatury klocków łożyskowych, na drodze obliczeń elasto-termo-hydrodynamicznych, stwierdzono konieczność wyrównania rozkładu obciążenia na poszczególne klocki łożyska. Cel został osiągnięty poprzez wprowadzenie podatnego podparcia segmentów łożyska na sprężynach płytowych, których...
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A Trisection Filter Design With Negative Slope of Frequency-Dependent Crosscoupling Implemented in Substrate Integrated Waveguide (SIW)
PublikacjaThis letter reports on a novel realization of a microwave bandpass filter in a triplet configuration with a frequency-dependent crosscoupling implemented in substrate integrated waveguide (SIW). The design involves implementing dispersive coupling with a negative slope, a feature that allows the capabilities of the classic triplet topology to be extended. In this particular case, the implementation of two transmission zeros on...
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On rotary inertia of microstuctured beams and variations thereof
PublikacjaWe discuss the classic rotary inertia notion and extend it for microstructured beams introducing new microinertia parameters as an additional dynamic response to microstructure changes. Slender structures made of beam- or platelet-lattice metamaterials may exhibit not only large translations and rotations but also general deformations of inner structure. Here we considered a few examples of beam-like structures and derive their...
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“Project-factor-decision”. Decisive factors in IT projects and their impact on its success
PublikacjaThe aim of this article is to indicate the need for a deepening, systematizing and codifying of the theoretical and practical knowledge on IT project management, in the area of management decision-making processes. The scope of decisions made by managers is constantly on the increase. Project managers make decisions not only within the classic triangle of constraints, which consists of a schedule, a budget and the project scope,...
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Microbial fuel cell applications for removal of petroleum hydrocarbon pollutants: A review
PublikacjaBioelectrochemical systems (BESs) are considered as the potential approaches to remediate the environments contaminated by hydrocarbons. This review addresses the application of BESs particularly microbial fuel cells (MFCs) in degradation of petroleum hydrocarbons, including BTEXs, from soil, water, wastewater and sediments. Details on reactor design and critical issues are discussed. Aspects on electrodes, redox mediators and...
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Identification of Bodner-Partom Viscoplastic Model Parameters for Some Aluminum Alloys at Elevated Temperature
PublikacjaThe paper presents the identification process of inelastic (viscoplastic) properties for two aluminum alloys at a temperature of 120°C. The material parameters are calculated on the basis of uniaxial tension tests. Twelve tests at elevated temperature for each alloy have been performed—three tests for four different strain rates. The main purpose of the paper is to identify the Bodner-Partom viscoplastic model parameters for two...
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Vibrational excitation of acetylene by positron impact
PublikacjaVibrationally inelastic quantum calculations are carried out at low collision energies for the scattering of a beam of positrons off acetylene gaseous molecules. The normal mode analysis is assumed to be valid and the relative fluxes into the C–C and C–H symmetric vibrational modes are computed within a Body-Fixed (BF) formulation of the dynamics by solving the relevant vibrational Coupled Channels (VCC) equations. The clear dominance...
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Regression points in non-intrusive polynomial chaos expansion method and D-optimal design
PublikacjaThe paper addresses selected issues of uncertainty quantification in the modelling of a system containing surgical mesh used in ventral hernia repair. Uncertainties in the models occur e.g. due to variability of abdominal wall properties among others. In order to include them, a non-intrusive regression-based polynomial chaos expansion method is employed. Its accuracy depends on the choice of regression points. In the study a relation...
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Metody strukturalnej analizy ontologii opartych na logice opisowej
PublikacjaW rozprawie przedstawiono opracowaną przez autora metodę wewnętrznej reprezentacji ontologii opartych na logice opisowej: kartografię wiedzy. Metoda ta służy przede wszystkim zwiększeniu efektywności wnioskowania dla baz wiedzy zawierających dużą liczbę asercji. W pracy przedstawiono formalizm opracowanej metody oraz towarzyszące jej algorytmy. Kartografię wiedzy wykorzystano w ramach projektu PIPS (6. Program Ramowy UE), a testy...
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Ontologie jako metoda reprezentacji wiedzy
PublikacjaLogika opisowa (ang. Description Logic - DL) jest aktualnie jednym z najsilniej rozwijanych formalizmów stosowanych w ontologicznych metodach reprezentacji wiedzy. Jednym z powodów jest to, że język OWL-DL, promowany przez W3C jako język do reprezentacji ontologii internetowych, opary jest właśnie na logice opisowej. W tym artykule zaprezentowano logikę opisową jako sposób precyzyjnego formułowania i przetwarzania wiedzy. Podano...
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Modelling of the Baumann turbine stage operation Part II. Free and kinetic vibrations
PublikacjaIn this paper has been presented a methodology of validation a novel mathematical model dedicated to evaluation and prediction of material degradation and demage of steam turbine elements such as blades, valves and pipes due to three mechanisms: stress-corosion, high-temperature creep and low-cyclic fatigue. The validation concept is based on an experimental setup manufactured in the Laboratory of Faculty of Mechanical and Power...
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Comparison of Surface Quality and Tool-Life of Glulam Window Elements after Planing
PublikacjaThe quality of the surface of wooden elements, that have been planed, has a crucial importance in the whole production process, since the obtained effects affect the quality of wooden surface after fi nishing (painting). The occurrence of defects is usually the reason for qualifying a workpiece as scrap or for requiring additional work. This paper presents the selected results of research of the effect of the cutting tool wear...
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SILICA AEROGEL TOWARDS ANODES FOR LITHIUM-ION BATTERIES
PublikacjaAn increasing demand for electrochemical energy storage and conversion devices stimulates progress in research on electrode and electrolyte materials. In the field of electrodes materials, silicon is the one of the most promising anode materials for Li-ion batteries. However silicon has the drastic volume variation (around 3 times lower on extraction) during insertion and extraction of lithium ions. As an alternative, nanocomposites...
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Recycling of Industrial Waste as Soil Binding Additives—Effects on Soil Mechanical and Hydraulic Properties during Its Stabilisation before Road Construction
PublikacjaTo improve the in situ soil stabilization, different chemical additives are used (ion exchange compounds, additives based on H2SO4 or vinyl polymers, and organic additives using lignosul- fonates). One interesting alternative is the production of additives from various waste materials. The extensive testing of waste-based blends with soil was performed; the mechanical (unconfined compressive strength (UCS)) and hydraulic (capillary...
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UNDERWATER NOISE GENERATED BY A SMALL SHIP IN THE SHALLOW SEA
PublikacjaStudy of the sea noise has been a subject of interest for years. The first work of this scope were published at the turn of the twentieth century by Knudsen (KNUDSEN et al., 1948) and G. Wenz (WENZ, 1962). Disturbances called "shipping noise" are one of the important components of the sea noise. In this work the results of an experimental research of underwater noise produced by a small ship of a classic propulsion are...
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Molecular geometry and optical activity of helically chiral N-nitrosamines derived from 1,2,3,4-tetrahydro- and 1,2,3,4,7,8,9,10-octahydro-1,10-phenanthroline
PublikacjaX-ray crystallographic analysis of the title N-nitrosamines revealed that they assume helical conformations in the solid state. Nitrosamines 1b and 2b were resolved by inclusion crystallization with optically active diols (TADDOLs). The absolute configuration of the guest molecules in the complexes 1b·3b and 2b·3b was assigned as M. The optical activity of the resolved compounds is manifested by their solid state CD spectra, which...
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Coastal Cliffs Monitoring and Prediction of Displacements Using Terrestial Laser Scanning
PublikacjaCoastal cliffs are very sensitive to degradation caused by erosion and abrasion. Thus, it is very important to monitor susceptibility of the cliffs in terms of slope angles and ground fall resulting from vertical morphology of the cliffs. The results could be used for example to establish the boundaries of the safe investments zone or retreat infrastructure buildings in case of real threat such as degradation of the objects of...
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Full Network Coverage Monitoring Solutions – The netBaltic System Case
PublikacjaThis paper defines the problem of monitoring a specific network, and more precisely – part of reporting process, which is responsible for the transport of data collected from network devices to station managers. The environment requires additional assumptions, as a specific network related to the netBaltic Project is to be monitored. Two new monitoring methods (EHBMPvU and EHBMPvF) are proposed, which priority is full network coverage....
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Poroelastic Material for Urban Roads Wearing Courses
PublikacjaConventional road materials used for producing wearing courses of roads are based on mineral aggregate and bituminous or Portland cement binders. The road materials must be optimized for different properties, including skid resistance, durability, rolling resistance and tire/road noise. Unfortunately, it seems that within classic technologies it is very difficult to achieve further reduction of tire/road noise. Innovative porous...
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Noise effect on parameters of quiet sonar with code modulation
PublikacjaEarlier publications of the paper authors have shown that the use of code keying mixed with the CW FM sound signal allows the significant reduction in the distance measurement error, compared to classic silent CW FM sonar. In addition to the code modulation parameters, the magnitude of this error is influenced by the received input acoustic noise. The article shows the dependence of the input signal-to-noise ratio and the sound...
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Poroelastic Material for Urban Roads Wearing Courses
PublikacjaConventional road materials used for producing wearing courses of roads are based on mineral aggregate and bituminous or Portland cement binders. The road materials must be optimized for different properties, including skid resistance, durability, rolling resistance and tire/road noise. Unfortunately, it seems that within classic technologies it is very difficult to achieve further reduction of tire/road noise. Innovative porous...
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Properties comparison of rubber and three layer PTFE-NBR-bronze water lubricated bearings with lubricating grooves along full bush circumference based on experimental tests
PublikacjaWater lubricated bearings have been in industrial use for well over a century. During the last decade their traditional range has been expanded with new, modern products. Despite that fact, certain solutions continue to employ the standard rubber bearing with lubricating grooves located along entire bush circumference. The work presents experimental research conducted on comparable sliding bearings with lubrication grooves along...