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Analysis of the Possibility of Using New Types of Protective Coatings and Abrasion-Resistant Linings under the Operating Conditions of the Spiral Classifier at KGHM Polska Miedź S.A. Ore Concentration Plant
PublikacjaA study was carried out to select the appropriate coatings for corrosion protection of the spiral classifier working at KGHM Polska Miedź S.A. Ore Concentration Plant. The abrasion resistance of selected protective coatings and wear-resistant linings was investigated using a DT-523 rotary abrasion tester with Taber CS-10 rubber abrasive discs. The average weight loss of the coatings after a cycle of 2000 revolutions was determined....
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The fracture behaviour of notched PMMA specimens under simple loading conditions – Tension and torsion experimental tests
PublikacjaThis paper presents the results of experimental testing of flat PMMA specimens during uniaxial loading conditions. Two separate tests were conducted: tensile and torsion. The specimens were weakened with V-type edge notches with different root radii: 0.5; 2 and 10 mm. The specimens were made in two thickness variants: 5 and 15 mm. Monotonic tensile and torsion tests were carried out while keeping the averaged strain rate constant,...
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Medical-Grade PCL Based Polyurethane System for FDM 3D Printing—Characterization and Fabrication
PublikacjaThe widespread use of three-dimensional (3D) printing technologies in medicine has contributed to the increased demand for 3D printing materials. In addition, new printing materials that are appearing in the industry do not provide a detailed material characterization. In this paper, we present the synthesis and characterization of polycaprolactone (PCL) based medical-grade thermoplastic polyurethanes, which are suitable for forming...
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Review of Selected Methods for Prediction of Added Resistance in Following Waves
PublikacjaThe added resistance in waves is a mean value of non-linear, second order reaction of a ship to incoming waves. In the beginning of the 20th century, the experimental methods for investigation of ship hydrodynamics at model scale were developed. They allowed the evaluation of added resistance by measurements in irregular waves (directly) or by measurements in regular waves (in-direct method). The main goal was to find more precise...
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Wpływ wybranych właściwości maszyny badawczej na wynik eksperymentu tribologicznego z tarciem ślizgowym
PublikacjaNiniejsza monografia stanowi podsumowanie przekrojowych badań związanych z wpływem właściwości stanowiska badawczego (tribometru) na przebieg i rejestrowane wyniki eksperymentu tribologicznego z tarciem ślizgowym ciał stałych smarowanych cieczą w warunkach tarcia bez efektów smarowania hydrodynamicznego. Autor przedstawia wyniki kompleksowych analiz właściwości dynamicznych stanowiska badawczego w kontekście efektów obserwowanych...
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Synchronization system for underwater acoustic communications using in shallow waters
PublikacjaA reliable synchronization system of the transmitted data frame has a significant impact on the efficiency of the underwater communication system. This applies in particular to communication systems dedicated to work in shallow waters, where the phenomenon of multipath permanently occurs. To overcome these difficulties, the concept of a synchronization system consisting of two broadband signals of opposite monotonicity was presented....
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Ship Dynamic Positioning Based on Nonlinear Model Predictive Control
PublikacjaThe presented work explores the simulation test results of using nonlinear model predictive control algorithm for ship dynamic positioning. In the optimization task, a goal function with a penalty was proposed with a variable prediction step. The results of the proposed control algorithm were compared with backstepping and PID. The effect of estimation accuracy on the control quality with the implemented algorithms was investigated....
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Model of heat transfer in the stagnation point of rapidly evaporating microjet
PublikacjaThe paper presents investigation into the single water microjet surface cooling producing evaporating film. Reported tests were conducted under steady state conditions. Experiments were conducted using the nozzle size of 70 and 100 mikrometer respectively. In the course of investigations obtained were experimental relations between heat flux and wall superheating. It was proved that the phenomenon is similar to that of pool boiling...
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Numerical analysis on axial capacity of steel built-up battened columns
PublikacjaThis paper deals with the numerical analysis aimed at study the bearing capacity of pinended steel built-up columns under axial compression. Finite element (FE) models were performed for the columns presented in the literature. The main problem discussed in the article is the shape and magnitude of geometric imperfections introduced into the numerical FE model, necessary to obtain the load capacity consistent with the experimental...
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VIbration monitoring in reciprocating siding friction tests. Ball-on-flat contact. Sintered alumina ceramics (98%). Lubricant - PARAFFIN OIL. Specim. set K09A - full-run
Dane BadawczeVIbration monitoring in reciprocating siding friction tests in ball-on-flat contact. Both specimens made of sintered alumina ceramics (98%) - self-mated contact.Linear reciprocating motion.Lubrication: PARAFFIN OIL. Sliding velocity (peak): 0.1 m/s. Load (normal force): 5N. Test rig: TPZ-1 Tribometer.Running time: progressive increments of 10, 15, 30,...
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VIbration monitoring in reciprocating siding friction tests. Ball-on-flat contact. Sintered alumina ceramics (98%). Lubricant - PARAFFIN OIL. Specim. set K09 - pre-run
Dane BadawczeVIbration monitoring in reciprocating siding friction tests in ball-on-flat contact. Both specimens made of sintered alumina ceramics (98%) - self-mated contact.Linear reciprocating motion.Lubrication: PARAFFIN OIL. Sliding velocity (peak): 0.1 m/s. Load (normal force): 5N. Test rig: TPZ-1 Tribometer.Running time: progressive increments of 10, 15, 30,...
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VIbration monitoring in reciprocating siding friction tests. Ball-on-flat contact. Sintered alumina ceramics (98%). No lubrication (DRY). Specim. set K05
Dane BadawczeVIbration monitoring in reciprocating siding friction tests in ball-on-flat contact. Both specimens made of sintered alumina ceramics (98%) - self-mated contact.Linear reciprocating motion.Lubrication: DRY. Sliding velocity (peak): 0.1 m/s. Load (normal force): 5N. Test rig: TPZ-1 Tribometer.Running time: progressive increments of 10, 15, 30, 60, 180...
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VIbration monitoring in reciprocating siding friction tests. Ball-on-flat contact. Sintered alumina ceramics (98%). Lubricant - PARAFFIN OIL. Specim. set K08
Dane BadawczeVIbration monitoring in reciprocating siding friction tests in ball-on-flat contact. Both specimens made of sintered alumina ceramics (98%) - self-mated contact.Linear reciprocating motion.Lubrication: PARAFFIN OIL. Sliding velocity (peak): 0.1 m/s. Load (normal force): 5N. Test rig: TPZ-1 Tribometer.Running time: progressive increments of 10, 15, 30,...
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VIbration monitoring in reciprocating siding friction tests. Ball-on-flat contact. Sintered alumina ceramics (98%). Lubricant - DISTILLED WATER. Specim. set K02
Dane BadawczeVIbration monitoring in reciprocating siding friction tests in ball-on-flat contact. Both specimens made of sintered alumina ceramics (98%) - self-mated contact.Linear reciprocating motion.Lubrication: DISTILLED WATER. Sliding velocity (peak): 0.1 m/s. Load (normal force): 5N. Test rig: TPZ-1 Tribometer.Running time: progressive increments of 10, 15,...
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VIbration monitoring in reciprocating siding friction tests. Ball-on-flat contact. Sintered alumina ceramics (98%). Lubricant - DISTILLED WATER. Specim. set K06
Dane BadawczeVIbration monitoring in reciprocating siding friction tests in ball-on-flat contact. Both specimens made of sintered alumina ceramics (98%) - self-mated contact.Linear reciprocating motion.Lubrication: DISTILLED WATER. Sliding velocity (peak): 0.1 m/s. Load (normal force): 5N. Test rig: TPZ-1 Tribometer.Running time: progressive increments of 10, 15,...
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VIbration monitoring in reciprocating siding friction tests. Ball-on-flat contact. Sintered alumina ceramics (98%). Lubricant - DISTILLED WATER. Specim. set K07
Dane BadawczeVIbration monitoring in reciprocating siding friction tests in ball-on-flat contact. Both specimens made of sintered alumina ceramics (98%) - self-mated contact.Linear reciprocating motion.Lubrication: DISTILLED WATER. Sliding velocity (peak): 0.1 m/s. Load (normal force): 5N. Test rig: TPZ-1 Tribometer.Running time: progressive increments of 10, 15,...
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VIbration monitoring in reciprocating siding friction tests. Ball-on-flat contact. Sintered alumina ceramics (98%). No lubrication (DRY). Specim. set K03
Dane BadawczeVIbration monitoring in reciprocating siding friction tests in ball-on-flat contact. Both specimens made of sintered alumina ceramics (98%) - self-mated contact.Linear reciprocating motion.Lubrication: DRY. Sliding velocity (peak): 0.1 m/s. Load (normal force): 5N. Test rig: TPZ-1 Tribometer.Running time: progressive increments of 10, 15, 30, 60, 180...
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VIbration monitoring in reciprocating siding friction tests. Ball-on-flat contact. Sintered alumina ceramics (98%). No lubrication (DRY). Specim. set K04
Dane BadawczeVIbration monitoring in reciprocating siding friction tests in ball-on-flat contact. Both specimens made of sintered alumina ceramics (98%) - self-mated contact.Linear reciprocating motion.Lubrication: DRY. Sliding velocity (peak): 0.1 m/s. Load (normal force): 5N. Test rig: TPZ-1 Tribometer.Running time: progressive increments of 10, 15, 30, 60, 180...
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VIbration monitoring in reciprocating siding friction tests. Ball-on-flat contact. Sintered alumina ceramics (98%). No lubrication (DRY). Specim. set K01
Dane BadawczeVIbration monitoring in reciprocating siding friction tests in ball-on-flat contact. Both specimens made of sintered alumina ceramics (98%) - self-mated contact.Linear reciprocating motion.Lubrication: DRY. Sliding velocity (peak): 0.1 m/s. Load (normal force): 5N. Test rig: TPZ-1 Tribometer.Running time: progressive increments of 10, 15, 30, 60, 180...
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Numerical model for thin liquid film with evaporation and condensation on solid surfaces in systems with conjugated heat transfer
PublikacjaCondensation and evaporation processes from wetted surfaces are of utmost importance in many technological or industrial applications. In many devices such as home-appliances and air conditioning systems just to name a few, condensation and evaporation processes greatly impact their performance and energy efficiency; The physics of these processes is quite complex, involving conjugate heat transfer among solid–liquid film-gaseous...
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Integration and verification of meteorological observations and NWP model data for the local GNSS tomography
PublikacjaGNSS meteorology applies the Global Navigation Satellite Systems (GNSS) to derive information about the state of the atmosphere (particularly troposphere). The tomography is one of the methods used in GNSS meteorology. The input data of GNSS tomography are the signal troposphere delays, results of GNSS data processing and additionally meteorological observations and Numerical Weather Prediction (NWP) models data. Different types...
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Debonding of coin-shaped osseointegrated implants: Coupling of experimental and numerical approaches
PublikacjaWhile cementless implants are now widely used clinically, implant debonding still occur and is difficult to anticipate. Assessing the biomechanical strength of the bone–implant interface can help improving the understanding of osseointegration phenomena and thus preventing surgical failures. A dedicated and standardized implant model was considered. The samples were tested using a mode III cleavage device to assess the mechanical...
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Inverse Nonlinear Eigenvalue Problem Framework for the Synthesis of Coupled-Resonator Filters With Nonresonant Nodes and Arbitrary Frequency-Variant Reactive Couplings
PublikacjaA novel, general circuit-level description of coupledresonator microwave filters is introduced in this article. Unlike well-established coupling-matrix models based on frequency-invariant couplings or linear frequency-variant couplings (LFVCs), a model with arbitrary reactive frequencyvariant coupling (AFVC) networks is proposed. The engineered formulation is more general than prior-art ones—with the only restriction that the coupling...
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AN ENERGY APPROACH TO THE FATIGUE LIFE OF SHIP PROPULSION SYSTEMS
PublikacjaThe conducted research investigations aimed to carry out an identification of the constructional materials fatigue state of the ship propulsions’ rotational mechanical units for diagnostic purposes. The fatigue cracks of the elements transmitting mechanical energy streams from the propulsion engines to the ship propellers or to the generators of the ship’s electric power station stand for a primary reason for the secondary, usually...
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BADANIE WPŁYWU INDUKCJI REMANENCJI NA STAN PRZEJŚCIOWY JEDNOFAZOWEGO UKŁADU TRANSFORMATOROWEGO
PublikacjaW referacie przedstawiono wyniki badań eksperymentalnych i symulacyjnych wpływu indukcji remanencji w rdzeniu transformatora jednofazowego na jego stan przejściowy przy jego pracy jałowej. Badany obiekt jest układem transformatorowym o dwóch uzwojeniach nawiniętych na zwijanym z blachy anizotropowej rdzeniu w kształcie toroidu. Doświadczenia eksperymentalne polegały na rozładowywaniu kondensatora przez uzwojenie strony pierwotnej...
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Multicomponent ionic liquid CMC prediction
PublikacjaWe created a model to predict CMC of ILs based on 704 experimental values published in 43 publications since 2000. Our model was able to predict CMC of variety of ILs in binary or ternary system in a presence of salt or alcohol. The molecular volume of IL (Vm), solvent-accessible surface (Sˆ), solvation enthalpy (DsolvGN), concentration of salt (Cs) or alcohol (Ca) and their molecular volumes (Vms and Vma, respectively) were chosen...
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Cost-efficient design optimization of compact patch antennas with improved bandwidth
PublikacjaIn this letter, a surrogate-assisted optimization procedure for fast design of compact patch antennas with enhanced bandwidth is presented. The procedure aims at addressing a fundamental challenge of the design of antenna structures with complex topologies, which is simultaneous adjustment of numerous geometry parameters. The latter is necessary in order to find a truly optimum design and cannot be executed-at the level of high-fidelity...
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Dynamiczna aplikacja Internetowa ASP.NET silnika indukcyjnego jako elementu wirtualnego laboratorium maszyn elektrycznych
PublikacjaTematem referatu jest dynamiczna aplikacja internetowa, która umożliwia symulację obwodową silnika indukcyjnego trójfazowego Sg 100 L2 z wykorzystaniem interfejsu przeglądarki WWW. Model matematyczny silnika jest zdefiniowany w tzw. osiach naturalnych i sformułowany na podstawie metody energetycznej Lagrange’a. Do implementacji modelu maszyny w aplikacji internetowej wybrano projekt typu Web Forms, który jest składnikiem środowiska...
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How to model ROC curves - a credit scoring perspective
PublikacjaROC curves, which derive from signal detection theory, are widely used to assess binary classifiers in various domains. The AUROC (area under the ROC curve) ratio or its transformations (the Gini coefficient) belong to the most widely used synthetic measures of the separation power of classification models, such as medical diagnostic tests or credit scoring. Frequently a need arises to model an ROC curve. In the biostatistical...
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Mathematical model of the energy consumption calculation during the pine sawn wood (Pinus sylvestris L.) drying process
PublikacjaThe article presents the modification of the existing mathematical model to calculate energy consumption during conventional drying process. Apart from energy consumption the model permits to estimate the time of high-temperature drying process. The drying medium is air and superheated steam mixture. The obtained calculation results were compared with conducted experimental tests of drying square-edged sawn sapwood timber (Pinus...
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EMISJA AKUSTYCZNA JAKO SYGNAŁ DIAGNOSTYCZNY ODWZOROWUJĄCY ZMĘCZENIOWE ZUŻYCIE WARSTW ŚLIZGOWYCH PANWI ŁOŻYSK GŁÓWNYCH I KORBOWYCH SILNIKÓW O ZAPŁONIE SAMOCZYNNYM
PublikacjaW artykule przedstawiono wyniki badań laboratoryjnych, z których wynika, że emisja akustyczna (EA) może być uznana za sygnał diagnostyczny, przydatny do identyfikacji stanu technicznego łożysk głównych i korbowych okrętowych silników o zapłonie samoczynnym. Wykazano w nim bowiem, że parametry emisji akustycznej takie jak: czas rejestracji, energia sygnału, amplituda sygnału, ilość przekroczeń poziomu dyskryminacji, czas narastania,...
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Effects of Noncontact Shoulder Tool Velocities on Friction Stir Joining of Polyamide 6 (PA6)
PublikacjaIn this study, the effects of the traverse and rotational velocities of the noncontact shoulder tool on the heat generation and heated flux during the friction stir joining of high-density polyamide 6 (PA6) polymer were investigated. The computational fluid dynamics (CFD) method was employed to simulate the thermomechanical phenomena during the friction stir joining (FSJ) process of PA6. A developed model was used to consider the...
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Ship Evolutionary Trajectory Planning Method with Application of Polynomial Interpolation
PublikacjaPaper presents the application of evolutionary algorithms and polynomial interpolation in ship evolutionary trajectory planning method. Evolutionary algorithms allows to find a coIlision free trajectory in real time, while polynomial interpolation allows to model smooth trajectory which keeps continuity of velocity and acceleration values along path. Combination of this two methods allows to find trajectory, which under some assumptions,...
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Audio codec employing frequency-derived tonality measure
PublikacjaA transform codec employing efficient algorithm for detection of spectral tonal components is presented. The tonality measure used in MPEG psychoacoustic model is replaced with the method providing adequate tonality estimates even if the tonal components are deeply frequency modulated. The reliability of hearing threshold estimated using psychoacoustic model with standardized tonality measure and the proposed one is investigated...
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New approach for determining the QoS of MP3-coded voice signals in IP networks
PublikacjaPresent-day IP transport platforms being what they are, it will never be possible to rule out conflicts between the available services. The logical consequence of this assertion is the inevitable conclusion that the quality of service (QoS) must always be quantifiable no matter what. This paper focuses on one method to determine QoS. It defines an innovative, simple model that can evaluate the QoS of MP3-coded voice data transported...
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Non-Adaptive Speed and Position Estimation of Doubly-Fed Induction Generator in Grid-Connected Operations
PublikacjaThe nonadaptive speed and position estimation scheme for a doubly-fed induction generator (DFIG) is presented in this article. The observer structure is based on the extension of the mathematical model of DFIG to the introduced H vector. Based on the defined H vector, the nonadaptive position and speed estimation is proposed. The Lyapunov method is extended to the practical stability theorem to stabilize the structure. The classic...
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Identification of Unstable Reference Points and Estimation of Displacements Using Squared Msplit Estimation
PublikacjaThe article presents a new version of the method for estimating parameters in a split functional model, which enables the determination of displacements of geodetic network points with constrained datum. The main aim of the study is to present theoretical foundations of Msplit CD estimation and its basic properties and possible applications. Particular attention was paid to the efficacy of the method in the context of geodetic...
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Image Segmentation of MRI image for Brain Tumor Detection
Publikacjathis research work presents a new technique for brain tumor detection by the combination of Watershed algorithm with Fuzzy K-means and Fuzzy C-means (KIFCM) clustering. The MATLAB based proposed simulation model is used to improve the computational simplicity, noise sensitivities, and accuracy rate of segmentation, detection and extraction from MR...
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Performance‐driven modeling of compact couplers in restricted domains
PublikacjaFast surrogate models can play an important role in reducing the cost of EM-driven design closure of miniaturized microwave components. Unfortunately, construction of such models is challenging due to curse of dimensionality and wide range of geometry parameters that need to be included in order to make it practically useful. In this letter, a novel approach to design-oriented modeling of compact couplers is presented. Our method...
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Rapid redesign of multiband antennas with respect to operating conditions and material parameters of substrate
PublikacjaThis work addresses geometry parameter scaling of multi-band antennas for Internet of Things applications. The presented approach is comprehensive and permits re-design of the structure with respect to both the operating frequencies and material parameters of the dielectric substrate. A two-step procedure is developed with the initial design obtained from an inverse surrogate model constructed using a set of appropriately prepared...
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Electrical Tree Growth Behavior Under AC and DC High Voltage in Power Cables
PublikacjaThis work investigates the impact of an applied AC and DC high voltage on the electrical tree behavior in extruded cross-linked polyethylene (XLPE) insulation based on simulation and experimental validation. Extensive partial discharge (PD) testing methods are being implemented for high voltage cables under AC voltage for monitoring their condition. However, these PD testing methods cannot be utilized for power cables under DC...
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Updating Finite Element Model of a Wind Turbine Blade Section Using Experimental Modal Analysis Results
PublikacjaThis paper presents selected results and aspects of themultidisciplinary and interdisciplinary research oriented for the experimental and numerical study of the structural dynamics of a bend-twist coupled full scale section of awind turbine blade structure.Themain goal of the conducted research is to validate finite elementmodel of themodified wind turbine blade section mounted in the flexible support structure accordingly to the...
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Modeling N2O behavior during denitrification with different carbon sources and electron acceptors
PublikacjaA mathematical model was developed for identification of the most important mechanism leading to nitrous oxide (N2O) accumulation in denitrifying activated sludge systems. The activated sludge model No. 2d (ASM2d) was extended to include intermediate three steps of the denitrification process. The formation and accumulation of nitric oxide (NO) was assumed to be very low in the performed laboratory experiments. These experiments...
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Examination of advanced isotropic constitutive laws under complex stress states in plain and reinforced concrete specimens
PublikacjaThe performance of advanced isotropic constitutive laws under complex stress states in plain and reinforced concrete specimens is investigated. Three different formulations are chosen: original Mazars model, Mazars mi model and model proposed by Pereira and coworkers. The degradation of the material in all formulations is described via a single variable, but a strain/stress state is taken into account via quite sophisticated relationships....
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Numerical investigation on dynamic performance of a multi-storey steel structure model and comparison with experimental results
PublikacjaShaking table testing is the most commonly adopted method to simulate earthquake forces. This approach allows us to analyze the dynamic performance and provides a valuable insight into the dynamics of building structures, which helps to improve their future safety and reliability. The present study aims to conduct a numerical evaluation of dynamic response of a multi-storey steel structure model, which was previously examined during...
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Numerical Investigation on Dynamic Performance of a Multi-storey Steel Structure Model and Comparison with Experimental Results
PublikacjaShaking table testing is the most commonly adopted method to simulate earthquake forces. This approach allows us to analyze the dynamic performance and provides a valuable insight into the dynamics of building structures, which helps to improve their future safety and reliability. The present study aims to conduct a numerical evaluation of dynamic response of a multi-storey steel structure model, which was previously examined during...
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Simplified AutoDock force field for hydrated binding sites
Publikacjahas been extracted from the Protein Data Bank and used to test and recalibrate AutoDock force field. Since for some binding sites water molecules are crucial for bridging the receptor-ligand interactions, they have to be included in the analysis. To simplify the process of incorporating water molecules into the binding sites and make it less ambiguous, new simple water model was created. After recalibration of the force field on...
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FE analysis of support-specimen interaction of compressive experimental test
PublikacjaThe objective of this work is to investigate the support-specimen interaction during the compressive experimental testing of stiffened plates. The interaction is analyzed employing the nonlinear Finite Element Method using the commercial software ANSYS. The connection between the stiffened plate and testing supports is modelled with the use of contact elements, where several possible interaction scenarios are investigated, and...
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Pedestrian on footbridges, vertical loads and response
PublikacjaThe paper is a synthesis of the experimental and theoretical investigations on dynamics of pedestrian bridges under vertical load The subject is divided into four issues.1) The pedestrian as a vertical dynamic load on footbridges, theoretic load function for walking and crouching.2) Crowd walking on the footbridge - pedestrian flow.3) Vertical lock-in effect.4) Response of the footbridge - numeric and side test results, -...
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Size effect in concrete under splitting tension
PublikacjaThe size effect is a fundamental phenomenon in concrete materials. It denotes that both the nominal structural strength and material ductility always decrease with increasing element size under tension. In the paper splitting tensile tests on cylindrical concrete specimens with the different diameter were carried out. Two types of the loading strip (plywood board and steel cylinder) were used. The concrete strength and ductility...