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The elasto-plastic numerical study of crack initiation in notched PMMA specimens under uniaxial loading conditions – Tension and torsion
PublikacjaThis paper presents the results of FEM numerical calculations aimed at describing the plastic strain and stress fields under critical loading conditions: tensile force or torsional moment. The calculations were carried out with reference to the results of experimental tensile and torsional tests of flat PMMA specimens weakened with V-notches of different root radii: 0.5, 2 and 10 mm. The procedure for conducting nonlinear numerical...
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Mapping knowledge risks: towards a better understanding of knowledge management
PublikacjaThis conceptual paper aims to identify, present, and analyze potential knowledge risks organizations might face. With the growing complexity of organizational environments and the plethora of new knowledge risks emerging, this critical but under-researched field of knowledge management (KM) deserves closer attention. The study is based on a critical analysis of the extant literature devoted to knowledge risks, discusses potential...
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Overview of the three multicriteria approaches applied to a global assessment of analytical methods
PublikacjaCritical and global evaluation of analytical methods should be one of the primary goals in analytical chemistry. A holistic approach, however, requires a look at the varied features: commonly discussed validation criteria, often underrated practical and economic aspects, and typically overlooked compliance with the principles of green analytical chemistry. Carrying out such an assessment in a critical and transparent way is extremely...
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Multi-stage magnetic-fluid seals for operating in water - life test procedure, test stand and research results. Part II Results of life tests of multi-stage magnetic - fluid seal operating in water
PublikacjaThe edge criteria for magnetic-fluid seals durability research were described in previous article [24] and now the tests results are presented. The tests were made with three magnetic fluids using various magnets quantity in magnetic assemblies. If values obtained in the repeated test deviated by more than 10 % from results of the first test an additional control test was made for final characteristics. The characteristics are:...
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Simulation Results of Dynamic Capacity Reallocation in Hierarchical Cell Structure of UMTS Network
PublikacjaIn the paper simulation results of dynamic capacity reallocation between different layers of hierarchical cell structure of UMTS network has been described. This approach for load management seems to be useful for improving the resource utilization perfmorance.
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Some Aspects of Shear Behavior of Soft Soil–Concrete Interfaces and Its Consequences in Pile Shaft Friction Modeling
PublikacjaThis paper examines the stiffness degradation and interface failure load on soft soil–concrete interface. The friction behavior and its variability is investigated. The direct shear tests under constant normal load were used to establish parameters to hyperbolic interface model which provided a good approximation of the data from instrumented piles. Four instrumented piles were used to obtain reference soil–concrete interface behavior....
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Prediction of fracture toughness in fibre-reinforced concrete, mortar, and rocks using various Machine learning techniques
PublikacjaMachine Learning (ML) method is widely used in engineering applications such as fracture mechanics. In this study, twenty different ML algorithms were employed and compared for the prediction of the fracture toughness and fracture load in modes I, II, and mixed-mode (I-II) of various materials, including fibre-reinforced concrete, cement mortar, sandstone, white travertine, marble, and granite. A set of 401 specimens of “Brazilian...
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Investigation on Mode I Fracture Behavior of Hybrid Fiber-Reinforced Geopolymer Composites
PublikacjaRecent reports in the literature have shown that fber-reinforced geopolymer composites (FRGC) made with monofbers exhibit a signifcant enhancement in fracture energy. However, many aspects of the fracture performance of hybrid fberreinforced geopolymer composites (HFRGC) remain largely unexploited, and these are predominant for the structures. For the frst time, the mode I fracture energy of HFRGC is investigated. The mode I behavior...
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Prediction of pile shaft capacity in tension based on some direct CPT methods – Vistula Marshland test site
PublikacjaThis paper presents different CPT methodologies for the prediction of the pile shaft resistance in tension on the example of three reference screw piles of the Jazowa test site in Poland. The shaft capacity was estimated based on the cone resistance, sleeve friction and CPT excess pore water pressure. Three piles with a diameter of 0.4 m and the length...
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A Comparison of the Efficiency of Deammonification under Different Aeration Strategies in a Laboratory-Scale Sequencing Batch Reactor
PublikacjaAn important source of nitrogen load entering the biological part of wastewater treatment plants (WWPTs) is derived from the anaerobic sludge digestion processes. Sludge digestion liquors constitute only 1-2% of the inflow to the plant, but the load of nitrogen directed with them to the main stream may be as high as 10-20% of the total nitrogen load. Therefore, numerous studies have focused on treatment of sludge digestion liquors...
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Lagrangian model of an isolated dc-dc converter with a 3-phase medium frequency transformer accounting magnetic cross saturation
PublikacjaThis article presents a nonlinear equivalent circuit model of an isolated dc-dc converter with a 3-phase medium frequency transformer. The model takes into account the magnetic cross saturation of the 3-phase core-type magnetic circuit. The model is suitable in detailed electromagnetic transient simulations of power systems involving isolated dc-dc converters. The model is developed using the Lagrange energy method. It involves...
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Dynamic mass measurement in checkweighers using a discrete time-variant low-pass filter
PublikacjaConveyor belt type checkweighers are complex mechanical systems consisting of a weighing sensor (strain gauge load cell, electrodynamically compensated load cell), packages (of different shapes, made of different materials) and a transport system (motors, gears, rollers). Disturbances generated by the vibrating parts of such a system are reflected in the signal power spectra in a form of strong spectral peaks, located usually in...
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Instrumented end notched flexure - Crack propagation and process zonemonitoring Part II: Data reduction and experimental
PublikacjaA mode II instrumented end notched flexure three point bending (ENF) adhesion test is described. The adhesive joint consists of two aluminium alloy (AW7075-T6) plates bonded with a structural epoxy adhesive (Hysol EA 9395™). Strain gauges are attached to the outer surface (backface) of the substrates in the lengthwise direction to measure local surface strain during crack propagation. Simultaneously, load/displacement measurements...
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Uniform expansion estimates in the quadratic map as a function of the parameter, with a large range of parameters
Dane BadawczeThis dataset contains selected results of numerical computations described in the paper "Quantitative hyperbolicity estimates in one-dimensional dynamics" by S. Day, H. Kokubu, S. Luzzatto, K. Mischaikow, H. Oka, P. Pilarczyk, published in Nonlinearity, Vol. 21, No. 9 (2008), 1967-1987, doi: 10.1088/0951-7715/21/9/002.
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Direct design of Controlled Modulus Columns (CMC) based on in-situ testing
PublikacjaIn this paper, the serviceability limit state and bearing capacity of tension screw displacement piles were analyzed using the results of static pile load tests, carried out on the test plot near the Elbląg city, and field, and laboratory tests. The paper presents the methodology of determining the pile load-settlement curve using different types of t-z transfer functions. The new method of constructing the pile load-settlement...
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Influence of the particle size of carbonate-siliceous rock on the efficiency of phosphorous removal from domestic wastewater
PublikacjatThe aim of the study was to determine the influence of the particle size of carbonate–silica rock (opoka)used in rock filters on the efficiency of phosphorus removal from domestic wastewater. The investigationswere carried out in a laboratory using a model consisting of three vertical flow filters with carbonate–silicarock of different particle sizes (G1= 1–2 mm; G2= 2–5 mm; G3= 5–10 mm). The tested rock was subjectedto decarbonising...
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TRANSFER OF ELECTRIC ENERGY [2023/24]
Kursy OnlineCourse content: Basic information on the structure of the power system, the major devices (components) for generation, transmission and distribution of electricity. Active and reactive power generation and their sources. Power supply networks. Tasks, structure, parameters. AC and DC transmission of electricity. Equivalent diagrams of the components of the power system. Steady state load flow calculation: currents, voltage,...
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TRANSFER OF ELECTRIC ENERGY [2022/23]
Kursy OnlineCourse content: Basic information on the structure of the power system, the major devices (components) for generation, transmission and distribution of electricity. Active and reactive power generation and their sources. Power supply networks. Tasks, structure, parameters. AC and DC transmission of electricity. Equivalent diagrams of the components of the power system. Steady state load flow calculation: currents, voltage,...
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MONITORING SYSTEM OF THE ROAD EMBANKMENT
PublikacjaThe paper presents the analysis of the monitoring system of the embankment supported on concrete columns and overlaid by a load transfer platform with the embedded steel grid. This field investigation was to study the complex interaction among the columns, the load transfer platform layer, and steel grid via in situ measurements during erection and live loading of the embankment. The study was focused on the behaviour of steel...
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Non-Salient Brushless Synchronous Generator Main Exciter Design for More Electric Aircraft
PublikacjaThis paper presents a prototype of high speed brushless synchronous generators (BSG) design for the application in autonomous electric power generation systems (e.g., airplane power grid). Commonly used salient pole field of the main generator part of BSG was replaced with a prototype non-salient pole field. The main objective of the research is an investigation into the advantages and disadvantages of a cylindrical field of the...
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Vibration monitoring of structures in the light of the Polish and international requirements
PublikacjaThe paper concerns the wide range of strategies used to protect structures against man-made dynamic excitation. The most popular approaches applied worldwide are compared, and the main differences and similarities are summarized. The literature studies are supported by the results of the measurements performed on different types of real structures, which are sensitive and insensitive to the dynamic load. To make the conclusions...
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Determination of mechanical properties of human stomach tissues subjected to uniaxial stretching
Dane BadawczeThe aim of the study was to determine the biomechanical properties of the walls of the human stomach. The samples were fragments of the human stomach obtained after sleeve gastrectomy. Samples cut parallel to the stomach curves and perpendicular to the stomach curves were tested in each series. All samples were subjected to uniaxial stretching. During...
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Results of nanoindentation test to calculate residual stress in an eyelet of undercarriage drag strut after laser treatment
Dane BadawczeIn order to determine the residual stress in the laser-processed an eyelet of undercarriage drag strut, a nanoindentation test was performed before and after stress relief annealing. For this purpose, after the hardness test, the sample was subjected to stress relief annealing at 270 °C for 2 hours. Annealing was performed in a vacuum furnace. Hardness...
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Zastosowanie szablonów Trust Case w pracy z normą BS 7799
PublikacjaTrust Case stanowi strukturę danych zawierającą argumentację oraz związany z nią materiał dowodowy uzasadniający, że interesujący nas obiekt (system, infrastruktura, organizacja) posiada wskazane własności. Wykorzystanie Trust Case do analizy i uzasadniania zaufania do systemów IT jest przedmiotem aktywnych badań. Podejście to znalazło zastosowanie w stosunku do systemów związanych z bezpieczeństwem (ang. safety critical), a ostatnio...
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Analytical approach for membrane action in laterally-restrained reinforced concrete square slabs under uniformly distributed loads
PublikacjaLaterally-restrained reinforced concrete slabs can mobilise compressive membrane action and subsequent tensile membrane action under extreme loading conditions, thereby enhancing the load resistance under uniformly distributed loads. Previous analytical study focuses primarily on tensile membrane action in simply-supported slabs. This paper describes an analytical approach for membrane action in laterally-restrained square slabs....
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Static Series and Shunt-series PE Voltage-quality Controllers
PublikacjaAs presented in the Chap. 7 static shunt power electronics (PE) voltage-quality controllers protect the utility electrical system from the unfavorable impact of customer loads. Shunt controllers, as shown in Chap. 6, are recommended mainly for mitigation of the causes of disturbances, and not their effects in distanced nodes of a power-electronics system. In the case when reduction of disturbances effects is required, which leads...
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INFLUENCE OF TIME ON THE BEARING CAPACITY OF PRECAST PILES
PublikacjaOne of the most popular types of foundations in layered subsoil with very differentiated soil shear strengths are precast piles. One of the reasons is a fact that we can well control the driving process during the installation of these piles. The principles of the assessment of bearing capacity and settlements of the piles given by Eurocode 7, concentrate on two main methods, i.e. Static Pile Load Tests (SPLT) and Dynamic Driving...
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Motor Cable Influence on the Conducted EMI Emission of the Converter Fed AC Motor Drive. - Vol. 1
PublikacjaInvestigation of conducted electromagnetic interference in AC motor drives fed by pulse width modulated voltage converters requires considering parasitic capacitances in converters, motor windings and feeding cables to be taken into account. Motor voltage transients and related conducted electromagnetic emission are significantly correlated with resonance effects occurring in load circuits. The levels of intensity of these phenomena...
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Experimental investigation of the PEM fuel cells performance for automotive and stationary applications
PublikacjaThe aim of the study was to provide dynamic characteristics of the PEM fuel cell system consisted of Nexa modules, provide steady-state characteristics of the for different values of air excess ratio and steady-state characteristics for different stack temperatures and given load.
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Threat intelligence platform for the energy sector
PublikacjaIn recent years, critical infrastructures and power systems in particular have been subjected to sophisticated cyberthreats, including targeted attacks and advanced persistent threats. A promising response to this challenging situation is building up enhanced threat intelligence that interlinks information sharing and fine-grained situation awareness. In this paper a framework which integrates all levels of threat intelligence...
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City walk: a didactic innovative experiment in architectural education
PublikacjaWalking is an activity that involves studying physical space and requires careful observation to be immersed in the surrounding reality. City walks are popular ways of encountering an urban space, spatial relation, its history, and recognising the problems and needs of space users, as well as future development of the city. City walks also may be educationally p owerful: the exploration of certain...
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Navier number and transition to turbulence
PublikacjaThe motivation behind this article is to explain a role of the Navier number (Na -dimensionless slip-length) in prediction of closures for laminar to turbulent transition undergoing via eddies detachment from the slip layer in nano-cannals. Additionally the role of the Navier number Na in universal modeling of phenomenon of enhanced mass flow rate reported in micro- and nano-channels has been explained. The Na number should be...
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Numerical Analysis of a Steel Frame Building with Soft-storey Failure under Ground Motion Excitation
PublikacjaThe aim of this paper is to show the results of a numerical analysis focused on the behaviour of multi-storey steel frame building that suffers from a soft-storey failure under ground motion excitation. A numerical model of the structure was created in FEM computer software and was exposed to an impact that would have been generated after a soft-storey failure due to falling of the upper floors. During the analysis, the whole structure...
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Particle Shape Effect on Macroscopic Behaviour of Underground Structures: Numerical and Experimental Study
PublikacjaThe mechanical performance of underground flexible structures such as buried pipes or culverts made of plastics depend not only on the properties of the structure, but also the material surrounding it. Flexible drains can deflect by 30% with the joints staying tight, or even invert. Large deformations of the structure are difficult to model in the framework of Finite Element Method, but straightforward in Discrete Element Methods....
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Dynamic impedance measurements of the Direct Methanol Fuel Cell cathode at various operating temperatures
PublikacjaThis article discusses the application of impedance analysis for diagnosing the cathode of a direct methanol fuel cell at various operating temperatures. The Dynamic Electrochemical Impedance Spectroscopy technique coupled with a linear current scan was applied for this purpose. This technique allowed the observation of changes in the cathode's properties in the fuel cell operating under real working conditions. An equivalent model...
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Dynamics of the small-span railway bridge under moving loads
PublikacjaThe paper presents the results of dynamic analysis of the small-span railway bridge, subjected to an action of moving trains. Numerical simulations were performed using three different load models: series of moving forces, series of moving single-mass and double-mass oscillators. The parameters of the vehicle were taken from the existing EN57 train. The parameters of the bridge were taken from the existing steel span of 10,24 m...
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The use of plate springs for preloading of a system of tapered roller bearings of a wind turbine gearbox
PublikacjaThe use of preloaded tapered roller bearings in wind turbine drive systems allows a transfer of load in the case of high variations of axial forces. The examined bearing system, a modification of a current design, consists of a pair of different sized bearings. Previous study showed the high sensitivity of tapered roller bearings on the existing radial interference. Dimensional tolerances used in the original design do not allow...
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Exhaust gas temperature measurements in diagnostic examination of naval gas turbine engines. Part I: Steady-state processes
PublikacjaThe article presents a possible method of detecting failures in the flow section and supply system of a naval gas turbine engine based on the exhaust gas temperature measured behind the gas generator. This temperature is a basic diagnostic parameter use for evaluating the technical state of the turbine engine in operation, and is monitored during engine start-ups, accelerations and decelerations of rotor units, and steady-load...
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Particle Shape Effect on Macroscopic Behaviour of Underground Structures: Numerical and Experimental Study
PublikacjaAbstract: The mechanical performance of underground flexible structures such as buried pipes or culverts made of plastics depend not only on the properties of the structure, but also on the material surrounding it. Flexible drains can deflect by 30% with the joints staying tight, or even invert. Large deformations of the structure are difficult to model in the framework of Finite Element Method, but straightforward in Discrete...
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Reactive Energy Billing in Operator Tariffs in Poland
PublikacjaThe paper describes the current method of reactive energy billing in the tariffs of distribution grid operators in Poland. The current solutions are subject to critical assessment. Issues related to the motivation effect of the current solutions on consumers are analysed. Problems that occur in relation with connecting distributed generators to the distribution grid and challenges related to prosumer billing are indicated.
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The effect of depth of surface layers constituted by vacuum technologies on pitting
PublikacjaThe paper presents the results of a study of the effect of vacuum technologies of formation of surface layers on pitting of associated elements in a lubricated, heavy-load rolling contact. The study has shown that increase in a PVD coat depth is accompanied by decrease in the fatigue friction pair.
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Uniform expansion estimates in the quadratic map as a function of the partition size, using Johnson’s algorithm
Dane BadawczeThis dataset contains selected results of numerical computations described in the paper "Quantitative hyperbolicity estimates in one-dimensional dynamics" by S. Day, H. Kokubu, S. Luzzatto, K. Mischaikow, H. Oka, P. Pilarczyk, published in Nonlinearity, Vol. 21, No. 9 (2008), 1967-1987, doi: 10.1088/0951-7715/21/9/002.
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Uniform expansion estimates in the quadratic map as a function of the partition size, computing λ only
Dane BadawczeThis dataset contains selected results of numerical computations described in the paper "Quantitative hyperbolicity estimates in one-dimensional dynamics" by S. Day, H. Kokubu, S. Luzzatto, K. Mischaikow, H. Oka, P. Pilarczyk, published in Nonlinearity, Vol. 21, No. 9 (2008), 1967-1987, doi: 10.1088/0951-7715/21/9/002.
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Uniform expansion estimates in the quadratic map as a function of the partition size, using the “derivative” partition type
Dane BadawczeThis dataset contains selected results of numerical computations described in the paper "Quantitative hyperbolicity estimates in one-dimensional dynamics" by S. Day, H. Kokubu, S. Luzzatto, K. Mischaikow, H. Oka, P. Pilarczyk, published in Nonlinearity, Vol. 21, No. 9 (2008), 1967-1987, doi: 10.1088/0951-7715/21/9/002.
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Uniform expansion estimates in the cubic map as a function of the parameter
Dane BadawczeThis dataset contains selected results of numerical computations described in the paper "Quantitative hyperbolicity estimates in one-dimensional dynamics" by S. Day, H. Kokubu, S. Luzzatto, K. Mischaikow, H. Oka, P. Pilarczyk, published in Nonlinearity, Vol. 21, No. 9 (2008), 1967-1987, doi: 10.1088/0951-7715/21/9/002.
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Uniform expansion estimates in the quadratic map as a function of the parameter, using the “uniform” partition type
Dane BadawczeThis dataset contains selected results of numerical computations described in the paper "Quantitative hyperbolicity estimates in one-dimensional dynamics" by S. Day, H. Kokubu, S. Luzzatto, K. Mischaikow, H. Oka, P. Pilarczyk, published in Nonlinearity, Vol. 21, No. 9 (2008), 1967-1987, doi: 10.1088/0951-7715/21/9/002.
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Uniform expansion estimates in the quadratic map as a function of the partition size, using the Floyd–Warshall algorithm
Dane BadawczeThis dataset contains selected results of numerical computations described in the paper "Quantitative hyperbolicity estimates in one-dimensional dynamics" by S. Day, H. Kokubu, S. Luzzatto, K. Mischaikow, H. Oka, P. Pilarczyk, published in Nonlinearity, Vol. 21, No. 9 (2008), 1967-1987, doi: 10.1088/0951-7715/21/9/002.
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Uniform expansion estimates in the quadratic map as a function of the parameter, using the “derivative” partition type
Dane BadawczeThis dataset contains selected results of numerical computations described in the paper "Quantitative hyperbolicity estimates in one-dimensional dynamics" by S. Day, H. Kokubu, S. Luzzatto, K. Mischaikow, H. Oka, P. Pilarczyk, published in Nonlinearity, Vol. 21, No. 9 (2008), 1967-1987, doi: 10.1088/0951-7715/21/9/002.
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Uniform expansion estimates in the unimodal map with γ=1.5 as a function of the parameter
Dane BadawczeThis dataset contains selected results of numerical computations described in the paper "Quantitative hyperbolicity estimates in one-dimensional dynamics" by S. Day, H. Kokubu, S. Luzzatto, K. Mischaikow, H. Oka, P. Pilarczyk, published in Nonlinearity, Vol. 21, No. 9 (2008), 1967-1987, doi: 10.1088/0951-7715/21/9/002.
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Uniform expansion estimates in the unimodal map with γ=2.5 as a function of the parameter
Dane BadawczeThis dataset contains selected results of numerical computations described in the paper "Quantitative hyperbolicity estimates in one-dimensional dynamics" by S. Day, H. Kokubu, S. Luzzatto, K. Mischaikow, H. Oka, P. Pilarczyk, published in Nonlinearity, Vol. 21, No. 9 (2008), 1967-1987, doi: 10.1088/0951-7715/21/9/002.
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Quasi-Static Response
PublikacjaConcern for the quasi-static response of ship and offshore structures, as required for safety and serviceability assessments. Attention shall be given to uncertainty quantification of quasi-static load and response analysis approaches, and their limitations, including exact and approximate methods for derivation of different acceptance criteria.
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Determination of mechanical properties of Ti13Nb13Zr cubes made with STL technology subjected to uniaxial compression
Dane BadawczeThe aim of the study was to determine the mechanical properties of Ti13Nb13Zr cubes made with STL technology (3D printing). The experiments were carried out on the Hung Ta universal test machine HT-2402. Cubes with the initial dimensions of 10x10x10 mm were subjected to compression by increasing force to over 80 kN. In various experiments, the angle...
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Field investigation of low-temperature cracking and stiffness moduli on selected roads with conventional and high modulus asphalt concrete
PublikacjaHigh Modulus Asphalt Concrete (HMAC) was introduced in Poland as a one of the solutions to the problem of rutting, type of deterioration common in the 1990s. After first encouraging trials in 2002 HMAC was widely used for heavily loaded national roads and motorways. However some concerns were raised about low-temperature cracking of HMAC. This was the main reason of the studies presented in this article were started. The article...
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FEM modelling of screw displacement pile interaction with subsoil
PublikacjaPredicting the-settlement characteristics of piles is an important element in the designing of pile foundations. The most reliable method in evaluating pile-soil interaction is the static load test, preferably performed with instrumentation for measuring shaft and pile base resistances. This, however, is a mostly post-implementation test. In the design phase, prediction methods are needed, in which numerical simulations play an...
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Technical and economic conditions of supplying residential consumers with heat from nuclear power plant
PublikacjaThe reduction of CO2 emission requires technological shift towards carbon-free options. Cogeneration of electricity and heat based on coal and natural gas will experience generation cost increase, if the costs of emissions are imposed on the plant operators. Therefore, nuclear and renewable options should be considered. In this paper, we present the concept of electricity and heat supply system with nuclear condensing turbine adapted...
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Mechanical behaviour of knit synthetic mesh used in hernia surgery
PublikacjaPurpose: There is a discussion in literature concerning mechanical properties and modelling of surgical meshes. An important feature of elastic modulus dependency on load history is taken into account in this paper, as implants are subjected to variable loading during human activity. The example of DynaMesh®-IPOM surgical implant is studied. Methods: The analysis is based on failure tension tests and cyclic loading and unloading...
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INFLUENCE OF MEASURING CONDITIONS ON TYRE/ROAD NOISE
PublikacjaA decisive factor for the development of tyres and road surfaces is the ability to conduct representative and reproducible measurements of selected characteristics related to the interaction of tyres and road surfaces. In terms of tyre/road noise measurements in Europe two methods described in ISO/FDIS 11819-2 and ECE Regulation No.117 are used. The latter is compulsory for assigning the tyre noise labels. The methodologies differ...
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Mechanizm współpracy z gruntem pali prefabrykowanych wbijanych w świetle próbnych obciążeń pali oprzyrządowanych
PublikacjaOpis badań i wyniki próbnych obciążeń statycznych dwóch pali prefabrykowanych wbijanych oprzyrządowanych w aparaturę do pomiaru rozkładu siły osiowej wzdłuż trzonu pala. Analiza wpływu czasu i procesu wbijania na charakterystykę osiadania pali prefabrykowanych wbijanych. Identyfikacja siły rezydualnej w palu prefabrykowanym wbijanym i jej wpływ na interpretację pomiarów ekstensometrycznych w próbnym obciążeniu pala. Wnioski na...
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Ground anchors diagnostic process based on elastic wave propagation method
PublikacjaThe paper is focused on analysis of elastic wave propagation in the context of diagnostics of ground anchors. Numerical simulations were performed to assess the possibility of evaluation of the anchorage quality. It was assumed that the quality and the load capacity of the anchor system directly depend on the length, on which mortar and steel cooperate.
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ANALYSIS OF WORKING CONDITIONS OF BEARINGS NO.1 & NO.2 OF TURBINE 13K200 AND DESIGN DEVELOPMENT OF NEW BEARINGS FOR THE TURBINE AFTER RETROFITTING
PublikacjaThe main goal of the work consisted of preparing an analysis of working conditions of bearings No.1 and No.2 in the existing turbine 13K200, as well as designing geometries of new bearings which would allow for their proper functioning in the turbine following its retrofitting (work under higher load).
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A concept of zero-dimensional and three-dimensional thermodynamic modelling of steam storage in a steam cycle
PublikacjaThis work presents the thermodynamic model of steam storage in a steam cycle. The innovative steam storage is an integral part of the unit and thus responds quickly to changes in load. This enhances the primary control reserve while maintaining high efficiency of energy conversion. With regard to power plants, it improves the operational safety of generation units, as it prevents boiler and turbines overload in the case of steep...
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Wstępna analiza zagrożenia podtopieniami w zlewni Potoku Strzyża w Gdańsku.
PublikacjaCharakterystyka sieci hydrograficznej Potoku Strzyża. Analiza zagrożenia podtopie - niami z wykorzystaniem hydraulicznego modelu potoku. Przedstawienie oraz analiza wyników obliczeń. Wstępne określenie odcinków newralgicznych z punktu widze - nia zagrożenia powodziowego. Wstępna analiza możliwych przyczyn występowania podtopień na terenie zlewni Potoku Strzyża.
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Analytical Techniques Used in Monitoring of Atmospheric Air Pollutants
PublikacjaThe air pollution monitoring is one of the most pressing environmental problems today. The paper describes common air pollutants, their interaction and impact on the environment, and classifies the techniques and methods applied in air studies. Furthermore, the review characterizes the selected collection and sampling techniques used for gas sample analysis. Finally, the schematic diagrams of typical designs of systems applied...
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Application of Passive Samplers in Monitoring of Organic Constituents of Air
PublikacjaThe principles of passive dosimetry, which has been known for over 100 years, are finding an ever increasing use in analytical practice and are being used as a convenient technique for isolation and enrichment of analytes from various environmental media. Due to its simplicity, a variety of designs, as well as the possibility of using a number of different final determination techniques, passive dosimetry has been applied in...
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The Use of Sensory Analysis Techniques to Assess the Quality of Indoor Air
PublikacjaThe quality of indoor air is one of the significant elements that influences people's well-being and health inside buildings. Emissions of pollutants, which may cause odor nuisance, are the main reason for people's complaints regarding the quality of indoor air. As a result, it is necessary to perform tests aimed at identifying the sources of odors inside buildings. The article contains basic information on the characteristics...
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Pesticide Analysis of Bee and Bee Product Samples
PublikacjaBee products possess therapeutic properties and are the source of many essential trace elements,which is why they are regarded as valuable food products. Honey bees may bring to thehive numerous contaminants deposited on the plants they visit, including pesticide withoutxenobiotics. The large-scale application of pesticides in agriculture and horticulture can lead tomass mortality among bees, and the chemicals find their way into...
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Sol-gel technique - a versatile tool for adsorbent preparation
PublikacjaPrzygotowanie próbek do analizy, w tym przede wszystkim izolacja i/lub wzbogacanie analitów stanowi kluczowy element każdej procedury analitycznej z zakresu oznaczania składników śladowych. Wyzwania analityczna są związane zarówno z właściwościami fizykochemicznymi samych analitów jak i składników matrycy oraz stosowanych sorbentów. Choć gama znanych sorbentów i faz stacjonarnych, które można wykorzystać w praktyce analitycznej...
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Determination of glucosinolates and their decomposition products-indoles and isothiocyanates in cruciferous vegetables
PublikacjaWyniki badań epidemiologicznych oraz wyniki doświadczeń prowadzonych na zwierzętach mogą być podstawą do tezy, że wysoki poziom spożycia warzyw z rodziny krzyżowych, takich jak brokuły, brukselka, kalafior, kapusta może chronić organizm ludzki przed rozwojem nowotworów. W związku z tym, wspomniane warzywa wzbudzają zainteresowanie badaczy jako potencjalne źródło substancji mogących znaleźć zastosowanie w profilaktyce chorób nowotworowych....
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Application of passive samplers in monitoring of organic constituents of air
PublikacjaTechnika dozymetrii pasywnej - znana od ponad 100 lat - cieszy się ciągłym zainteresowaniem i jest często wykorzystywana w różnych badaniach środowiskowych. Z powodu swej prostoty, różnorodności rozwiązań konstrukcyjnych i możliwości wykorzystania różnych technik oznaczeń końcowych, technika dozymetrii pasywnej może być zastosowana zarówno do oznaczeń związków organicznych jak i nieorganicznych, obecnych zarówno w powietrzu wewnętrznym,...
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Application of different sampling procedures in studies of composition of various types of runoff waters - a review
PublikacjaInformacje o metodyce pobierania próbek i położeniu stanowiska obserwacyjnego warunkują prawidłowy wynik analizy i możliwość porównania go z innymi danymi. W publikacji omówiono różne typy próbników stosowanych do pobierania próbek wód spływnych dostających się do środowiska w wyniku zmywania przez opady atmosferyczne zanieczyszczeń z takich powierzchni jak: arterie komunikacyjne, dachy budynków, obszary rolnicze i leśne oraz hałdy...
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Modern techniques of sample preparation for determination of organic analytes by gas chromatography
PublikacjaW pracy dokonano przeglądu szerokiego spektrum technik przygotowania próbki, ze szczególnym uwzględnieniem technik o charakterze prośrodowiskowym. Opisu technik dokonano pod kątem wykorzystywanych mechanizmów izolacji analitów oraz stosowanych rozwiązań aparaturowych. Przegląd rozwiązań aparaturowych uzupełniono o podstawy teoretyczne izolacji bazującej na zjawisku podziału analitów.
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Calibration of Passive Samplers for the Monitoring of Pharmaceuticals in Water-Sampling Rate Variation
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The Role of and the Place of Method Validation in the Quality Assurance and Quality Control (QA/QC) System
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Prospects for the Production, Research and Utilization of Reference Materials
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C-reactive protein as a diagnostic and prognostic factor of endometrial cancer
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Recent Developments in Methods of Analysis for Fluoride Determination
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Developments in Methods of Analysis for Naphthalene Sulfonates
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Liquid Crystals in Analytical Chemistry: A Review
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Application of Microextraction Techniques Including SPME and MESI to the Thermal Degradation of Polymers: A Review
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Bioactive compounds of potato (Solanum tuberosum L.) juice: from industry waste to food and medical applications
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Magnetic Covalent Organic Frameworks—Fundamentals and Applications in Analytical Chemistry
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Problems and chellenges to determine pesticide residues in bumblebees
PublikacjaBumblebees play an important role in t he pollination process of many crops and flowers. Therefore, taking action to protect and assess the impact of p esticides on these insects is fully justi fied. Pesticides may cause mortality and also sub-lethal effects that are not always directly visible. Bumblebees, like honeybees, can be used as indicators for environmental monitoring contamination. Two approaches are mainly used for the...
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New Polymeric Materials for Solid Phase Extraction
PublikacjaSolid phase extraction (SPE) is a popular sample preparation technique, which can be applied directly in gas–solid phase and liquid–solid phase, or indirectly to solid samples by using, e.g., thermodesorption with subsequent chromatographic analysis. Although SPE can be described as a physical extraction process involving a liquid phase and a solid phase, the increased use of packed sorbent formats seems to have led to a bias toward...
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Direct Analysis of Samples of Various Origin and Composition Using Specific Types of Mass Spectrometry
PublikacjaOne of the major sources of error that occur during chemical analysis utilizing the more conventional and established analytical techniques is the possibility of losing part of the analytes during the sample preparation stage. Unfortunately, this sample preparation stage is required to improve analytical sensitivity and precision. Direct techniques have helped to shorten or even bypass the sample preparation stage; and in this...
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A Comprehensive Review on Shilajit: What We Know about Its Chemical Composition
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Fate and analysis of pharmaceutical residues in the aquatic environment.
PublikacjaObecność pozostałości farmaceutyków w poszczególnych elementach środowiska stanowi nowe wyzwanie zarówno z punktu widzenia technologii oczyszczania wód i ścieków, jak i dla analityków, których zadaniem jest opracowanie nowych metodyk analitycznych. Wiele stosowanych leków nie jest w organizmie całkowicie rozkładanych. Często są one wydalane po nieznacznym przekształceniu,lub nawet w niezmienionej postaci. Opisano drogi...
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Trace analysis - challenges and problems
PublikacjaW pracy przedstawiono podstawowe problemy związane z oznaczaniem składników śladowych i ultraśladowych w próbkach o złożonym składzie matrycy. W oparciu o dane literaturowe omówiono sposoby zapobiegania błędom jakimi mogą być obarczone wyniki oznaczeń końcowych.
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Denudation - a convenient method of isolation and enrichment of analytes
PublikacjaW pracy przedstawiono: podstawy teoretyczne techniki denudacyjnej; rozwiązania konstrukcyjne podstawowych typów urządzeń denudacyjnych; obszar praktycznego wykorzystania technik denudacyjnych.
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Sample preparation and chromatographic analysis of acidic herbicides in soils and sediments
PublikacjaW pracy przedstawiono różne techniki przygotowania próbek i oznaczania herbicydów z grupy pochodnych fenoli i pochodnych kwasów karboksylowych w próbkach gleby. Opisano wybrane metody wzbogacania i izolacji analitów, m. in.: ekstrakcję za pomocą wodnych roztworów zasad i rozpuszczalników organicznych płynem w stanie nadkrytycznym, wodą w stanie podkrytycznym, cieczą pod zwiększonym ciśnieniem, cieczą wspomaganą mikrofalami. Niski...
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Modern techniques of extraction of organic analytes from environmental matrices.
PublikacjaW pracy przedstawiono usystematyzowane informacje dotyczące dostępnych jak i nowych technik izolacji i wzbogacania analitów organicznych przed etapem oznaczeń końcowych.
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Preparation of gaseous standard mixtures: methods for controlling the amount of components generated in the process of thermal decomposition of immobilized compounds.
PublikacjaGazowe mieszaniny wzorcowe odgrywają ważną rolę w ocenie metod analitycznych i urządzeń pomiarowych. W tym przypadku gazowe mieszaniny wzorcowe mogą być traktowane jako specjalny rodzaj materiału odniesienia.Proces walidacji wymaga użycia tzw. matrycowych materiałów odniesienia. Wybór techniki umożliwiającej uzyskanie gazowej mieszaniny wzorcowej o żądanych parametrach użytkowych zależy od natury składników mierzonych i gazu...
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Analytical procedures for PAH and PCB determination in water samples - error sources
PublikacjaW pracy przedstawiono poszczególne etapy procedury analitycznej wykorzystywanej do oznaczania analitów z grupy WWA i PCB w próbkach wody. Pokazano jakie problemy występują podczas oznaczania wyżej wymienionych analitów i jaki mogą mieć wpływ na końcowy wynik analizy.
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Solid Phase Microextraction: Apparatus, Sorbent Materials, and Application.
Publikacjahe primary objective of this review article is to strategically screen and highlight the advancements in the area of solid phase microextraction (SPME). The plenty of review articles have been written on different aspects of SPME, this review is dedicated to provide the brief but clear overview of the research footprints so produced from SPME. Some of the key advancements in types and designs, coating materials, coating strategies,...
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The Current State-of-the-Art in the Determination of Pharmaceutical Residues in Environmental Matrices Using Hyphenated Techniques
PublikacjaSeveral thousand tons of pharmaceuticals and their transformation products (metabolites and degradation products) are introduced into the environment each year. They affect both human health and the environment, therefore, analytical procedures enabling the determination of a wide range of pharmaceuticals at trace levelswithminimal effort, time, and energy are required. Nowadays, hyphenated techniques are commonly applied in pharmaceutical...
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Application of gas chromatography to the analysis of spirit-based alcoholic beverages
PublikacjaSpirit-based beverages are alcoholic drinks, which production processes are dependent on the type and origin of raw materials. The composition of this complex matrix is difficult to analyze and scientists commonly choose a gas chromatography techniques for this reason. With a wide selection of extraction methods and detectors it is possible to provide qualitative and quantitative analysis for many chemical compounds with a various...
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Devices for the production of reference gas mixtures
PublikacjaFor many years there has been growing demand for gaseous reference materials, which is connected with development in many fields of science and technology. As a result, new methodological and instrumental solutions appear that can be used for this purpose. Appropriate quality assurance/quality control (QA/QC) must be used to make sure that measurement data are a reliable source of information. Reference materials are a significant...
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The Progress in Electron Microscopy Studies of Particulate Matters to Be Used as a Standard Monitoring Method for Air Dust Pollution
PublikacjaThe present article reviews studies on air solid particles carried out with the use of electron microscopy. Particle analysis combining scanning and transmission electron microscopy (SEM and TEM) can be used to derive size-resolved information of the composition, mixing state, morphology, and complex refractive index of atmospheric aerosol particles. It seems that electron microscopy is more widely used in atmospheric particulate...
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The role and the place of method validation in the Quality Assurance and Quality Control (QA/QC) System
PublikacjaOznaczanie analitów na coraz niższych poziomach stężeń w próbkach charakteryzujących się coraz bardziej złożonym składem matrycy to jeden z głównych kierunków rozwojowych analityki chemicznej. Jest to zadanie niezwykle trudne i skomplikowane, w związku z czym stanowi wielkie wyzwanie dla analityków i wymaga zwrócenia uwagi na problem kontroli i zapewnienia jakości uzyskiwanych wyników (ang. Quality Assurance/Quality Control - QA/QC).W...
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Calixarenes as stationary phases in High Performance Liquid Chromatography
PublikacjaPraca przeglądowa przedstawia dotychczasowe metody syntezy faz stacjonarnych na bazie pochodnych kaliksarenów, kaliksrezorcyarenów i kalikspiroli chemicznie ziązanych z żelem krzemionkowym lub dynamicznie na nim obsadzonych. Podsumowano zastosowanie tych faz w rozdzielaniu szeregu klas związków organicznych i nieorganicznych metodą wysokosprawnej chromatografii cieczowej.
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Statistical evaluation of the effectiveness of different extraction techniques for determining robenidyne levels in poultry feed.
PublikacjaPoprzez zastosowanie testu Kruskala-Wallisa i chemometrycznej techniki analizy podobieństwa porównano efektywność sześciu różnych technik ekstrakcji (wytrząsanie, ekstrakcja w aparacie Soxhleta, w aparacie Soxteca, wspomaganej ultradźwiękami, wspomaganej promieniowaniem mikrofalowym oraz przyspieszonej ekstrakcji rozpuszczalnikiem) na podstawie wyników odzysku robenidyny z próbek paszy dla ptaków. W zależności od zastosowanej techniki...