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Analysis of surface roughness of chemically impregnated Scots pine processed using frame-sawing machine
PublicationThe objective of this work was to evaluate the effect of the impregnation process of pine wood (Pinus sylvestris L.) on roughness parameters of the surface processed on a frame sawing. The samples weredried and impregnated using a commercial procedure by a local company. The touch method withthe use of measuring stylus (pin) was employed to determine of surface roughness of the samplesconsidering parameters, namely, arithmetical...
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An Improved Method of Minimizing Tool Vibration during Boring Holes in Large-Size Structures
PublicationThe paper presents a thoroughly modified method of solving the problem of vibration suppression when boring large-diameter holes in large-size workpieces. A new approach of adjusting the rotational speed of a boring tool is proposed which concerns the selection of the spindle speed in accordance with the results of the simulation of the cutting process. This streamlined method focuses on phenomenological aspects and involves the...
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Surface modifcation of PMMA polymer detected by XPS
Open Research DataIn order to obtain the experimental specimens, four PMMA/PC61BM samples with the following mass proportions were prepared: 10%, 20%, 30%, and 40%. In addition, as a reference, a PMMA sample without PC61BM was prepared as well. For the fabrication process, PC61BM 99.5% (Solenne BV), chloroform HPLC (Sigma Aldrich), and PMMA (commercially available...
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Segmentation of academic community for the purposes of mobility plan development – case study of Gdansk University of Technology
PublicationThe objective of the paper is to analyse the structure of academic community for its transport behaviour and attitudes using the example of the Gdansk University of Technology (the GUT) in Poland. Once understood, the group can be divided into homogenous sub-groups and studied for their potential and ways to influence their behaviour, attitudes and transport patterns. The results may be used to develop dedicated actions designed...
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Electron collisions with methyl-substituted ethylenes: Cross section measurements and calculations for 2-methyl–2-butene and 2,3-dimethyl–2-butene
PublicationWe report electron-scattering cross sections determined for 2-methyl–2-butene [(H3C)HC==C(CH3)2] and 2,3-dimethyl–2-butene [(H3C)2C=C(CH3)2] molecules. Absolute grand-total cross sections (TCSs) were measured for incident electron energies in the 0.5–300 eV range, using a linear electron-transmission technique. The experimental TCS energy dependences for the both targets appear to be very similar with respect to the shape. In each...
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Robust estimation of deformation from observation differences for free control networks
PublicationDeformation measurements have a repeatable nature. This means that deformation measurements are performed often with the same equipment, methods, geometric conditions and in a similar environment in epochs 1 and 2 (e.g., a fully automated, continuous control measurements). It is, therefore, reasonable to assume that the results of deformation measurements can be distorted by both random errors and by some non-random errors, which...
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A fast time-frequency multi-window analysis using a tuning directional kernel
PublicationIn this paper, a novel approach for time-frequency analysis and detection, based on the chirplet transform and dedicated to non-stationary as well as multi-component signals, is presented. Its main purpose is the estimation of spectral energy, instantaneous frequency (IF), spectral delay (SD), and chirp rate (CR) with a high time-frequency resolution (separation ability) achieved by adaptive fitting of the transform kernel. We...
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Effect of pavement roughness and vehicle dynamic loads on decrease of fatigue life of flexible pavements
PublicationDue to the fact that pavement surfaces are not ideally even, dynamic loads of vehicle axles deviate from static loads. Higher dynamic loads contribute to faster pavement distress. The distribution of dynamic loads is similar to normal distribution and can be described by static load and factors DI (dynamic impact) and DLC (dynamic load coefficient). With the deterioration of pavement condition its evenness decreases as well and...
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Effective Air Quality Prediction Using Reinforced Swarm Optimization and Bi-Directional Gated Recurrent Unit
PublicationIn the present scenario, air quality prediction (AQP) is a complex task due to high variability, volatility, and dynamic nature in space and time of particulates and pollutants. Recently, several nations have had poor air quality due to the high emission of particulate matter (PM2.5) that affects human health conditions, especially in urban areas. In this research, a new optimization-based regression model was implemented for effective...
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Comparative study on total nitrogen prediction in wastewater treatment 1 plant and effect of various feature selection methods on machine learning algorithms performance
PublicationWastewater characteristics prediction in wastewater treatment plants (WWTPs) is valuable and can reduce the number of sampling, energy, and cost. Feature Selection (FS) methods are used in the pre-processing section for enhancing the model performance. This study aims to evaluate the effect of seven different FS methods (filter, wrapper, and embedded methods) on enhancing the prediction accuracy for total nitrogen (TN) in the WWTP...
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Modeling of pharmaceuticals mixtures toxicity with deviation ratio and best-fit functions models
PublicationThe present study deals with assessment of ecotoxicological parameters of 9 drugs (diclofenac (sodium salt), oxytetracycline hydrochloride, fluoxetine hydrochloride, chloramphenicol, ketoprofen, progesterone, estrone, androstenedione and gemfibrozil), present in the environmental compartments at specific concentration levels, and theirmutual combinations by couples against Microtox® and XenoScreen YES/YAS® bioassays. As the quantitative...
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Bi-GRU-APSO: Bi-Directional Gated Recurrent Unit with Adaptive Particle Swarm Optimization Algorithm for Sales Forecasting in Multi-Channel Retail
PublicationIn the present scenario, retail sales forecasting has a great significance in E-commerce companies. The precise retail sales forecasting enhances the business decision making, storage management, and product sales. Inaccurate retail sales forecasting can decrease customer satisfaction, inventory shortages, product backlog, and unsatisfied customer demands. In order to obtain a better retail sales forecasting, deep learning models...
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Variable Data Structures and Customized Deep Learning Surrogates for Computationally Efficient and Reliable Characterization of Buried Objects
PublicationIn this study, in order to characterize the buried object via deep-learning-based surrogate modeling approach, 3-D full-wave electromagnetic simulations of a GPR model has been used. The task is to predict simultaneously and independent of each characteristic parameters of a buried object of several radii at different positions (depth and lateral position) in various dispersive subsurface media. This study has analyzed variable...
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Sounding rocket temperature and heat transfer data
Open Research DataThis dataset contains temperature and heat transfer data measured during REXUS 25 sounding rocket HEDGEHOG Experiment launched from Esrange Space Centre, Kiruna, Sweden. For experiment details, please see:
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PROBABILISTIC ANALYSIS OF A SPACE TRUSS BY MEANS OF A MULTIDIMENSIONAL VARIABLE DESCRIPTION
PublicationThe objective of this paper is to present a variant of the point estimate method (PEM) to determine mean values and standard deviations of limit loads of engineering structures. This approach is illustrated by limit state analysis of a space truss, considering geometric and material imperfections. The calculations were performed for different random models, so the influence of random parameters on the limit load of the truss can...
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Quality of Analytical Results: Classifiying Errors and Estimating Measurement Uncertainty
PublicationThe most important parameter of each analytical result is its reliability. An analytical result is not a constant value; each result has two properties, error and uncertainty. The sources of both these parameters have to be known and their values determined (estimated). All analytical results are obtained by applying an appropriate measuring procedure. The need for reliable results requires application of reliable analytical procedures,...
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Microstructural and electrical properties of Y0.07Sr0.93-xTiO3-δ perovskite ceramics
PublicationIn order to find a relationship between electrical and microstructural properties, yttrium-doped strontiumtitanate (7 mol%) with various values of strontium nonstoichiometry was investigated and shown in this work.It has been observed that yttrium doping can affect the electrical properties of SrTiO3 to a great extent.Moreover, the microstructural and electrical properties can be influenced by strontium nonstoichiometry.The defect...
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Proton affinities of simple organic compounds
PublicationThe Restricted Hatree-Fock method with 6-311G** split-valence molecular orbitals basis sets has been applied to geometrical optimizations and calculations of total electronic, zero point vibrational energies and proton affinities at 298 K for small neutral and protonated alkanes, alcohols, acetic acid, methyl and ethyl acetate, acetone, and acetaldehyde. Calculated values of proton affinities are compared with experimental data.
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Improving voltage levels in low-voltage networks with distributed generation – case study
PublicationThe use of distributed generation in low-voltage networks may cause the voltage variation in them, within the wide range. In unfavourable circumstances, the voltage may reach unacceptable values. The paper presents the effect of distributed generation on voltage levels in a selected low-voltage rural distribution network in Poland. An analysis of possible methods for improving voltage levels in this network is conducted. The most...
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Using contextual conditional preferences for recommendation taska: a case study in the movie domain
PublicationRecommendation engines aim to propose users items they are interested in by looking at the user interaction with a system. However, individual interests may be drastically influenced by the context in which decisions are taken. We present an attempt to model user interests via a set of contextual conditional preferences. We show that usage of proposed preferences gives reasonable values of the accuracy and the precision even when...
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Innowacja urbanistyczna w kontekście kształtowania środowiska mieszkaniowego
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Wybrane zagadnienia optymalizacji organizacji ruchu kolejowego w celu minimalizacji kosztów energii elektrycznej
PublicationW artykule przedstawiono podział kosztów w transporcie kolejowym z uwzględnieniem kosztów wewnętrznych przedsiębiorstwa, do których zaliczają się między innymi koszty dostępu do infrastruktury, czy koszty energii. Stwierdzono, że przy odpowiedniej organizacji ruchu pociągów na sieci kolejowej, bez ponoszenia dodatkowych nakładów na infrastrukturę i specjalistyczne urządzenia, można znacznie ograniczyć zużycie energii, a co za tym...
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Iterative Global Sensitivity Analysis Algorithm with Neural Network Surrogate Modeling
PublicationGlobal sensitivity analysis (GSA) is a method to quantify the effect of the input parameters on outputs of physics-based systems. Performing GSA can be challenging due to the combined effect of the high computational cost of each individual physics-based model, a large number of input parameters, and the need to perform repetitive model evaluations. To reduce this cost, neural networks (NNs) are used to replace the expensive physics-based...
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Influence of Actual Curing Conditions on Mechanical Properties of Concrete in Bridge Superstructures
PublicationThis article presents the research on the mechanical characteristics of concrete in the construction of three concrete bridges. A system of recording the internal temperature of concrete and automatic control of laboratory ovens was used for specimen curing. This allowed the specimens to be cured under conditions similar to those occurring in the structure. Before the construction, reference blocks were used to define similar curing...
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How personality traits, sports anxiety, and general imagery could influence the physiological response measured by SCL to imagined situations in sports?
Open Research DataThe data were collected to understand how individual differences in personality (e.g. neuroticism), general imagery, and situational sports anxiety are linked to arousal measuring with skin conductance level (SCL) in situational imagery (as scripted for sport-related scenes). Thirty persons participated in the study, aged between 14 and 42 years, with...
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Calculations of material factors for a set of 20 thermistors
Open Research DataThe presented data set is part of the research aimed at determining the actual characteristics of each thermistor in a package of twenty NTC10k type sensors.
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Microstructural and electrical properties of Y0.07Sr0.93-xTiO3 perovskite ceramics
PublicationIn order to find a relationship between electrical and microstructural properties, yttrium-doped strontium titanate (7 mol%) with various values of strontium nonstoichiometry was investigated and shown in this work. It has been observed that yttrium doping can affect the electrical properties of SrTiO3 to a great extent. Moreover, the microstructural and electrical properties can be influenced by strontium nonstoichiometry. The...
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Estimation of the uncertainty of the AC/AC transducer output voltage
PublicationThe paper presents a methodology for estimating uncertainty of voltage transducers processing function, on the example of CYVS411D07 voltage transducers. The analysis was conducted using the method based on the GUM Guide propagation of uncertainty law and the determination of the coverage factor based on the effective number of degrees of freedom (t-Student distribution). The paper also presents example evaluation results of measured...
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Calculation of Induced Sheath Voltages in Power Cables – Single Circuit System versus Double Circuit System
PublicationThis paper presents comparison of values of induced sheath voltages in power cable metallic sheaths when one or two cables per phase are used. Calculation of voltages is performed for various phase sequences of the power cables. Three types of the sheaths bonding and earthing are considered. Shock hazard and voltage stress of non-metallic outer sheath of cables are evaluated. The proposed, optimal configuration of the power cable...
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The Method of Finding the Optimal Spindle Speed When Milling Flexible Details
PublicationThe paper presents a new method of vibration reduction during milling of flexible details. The method consists in selecting the optimal spindle speed, based on the natural frequency of the workpiece. For this purpose, an original method was created, which is based on minimizing the work of cutting forces in the direction of the depth of cutting. The effectiveness of the method has been proved by comparing the RMS values of vibration...
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Bondage number of grid graphs
PublicationThe bondage number b(G) of a nonempty graph G is the cardinality of a smallest set of edges whose removal from G results in a graph with domination number greater than the domination number of G. Here we study the bondage number of some grid-like graphs. In this sense, we obtain some bounds or exact values of the bondage number of some strong product and direct product of two paths.
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Microstructural and electrical properties of Y0:07Sr0:93−xTiO3− perovskite ceramics
PublicationIn order to find a relationship between electrical and microstructural properties, yttrium-doped strontium titanate (7 mol%) with various values of strontium nonstoichiometry was investigated and shown in this work. It has been observed that yttrium doping can affect the electrical properties of SrTiO3 to a great extent. Moreover, the microstructural and electrical properties can be influenced by strontium nonstoichiometry. The...
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Wpływ zmian dopuszczalnych wartości parametrów geometrycznych i kinematycznych na podatność modernizacyjną układów torowych
PublicationPodatnością modernizacyjną nazywamy stopień przystosowania analizowanego odcinka linii kolejowej do zmiany prędkości eksploatacyjnej. Skala możliwych zmian prędkości (w sensie jej zwiększenia) jest wypadkową istniejącego układu geometrycznego linii w planie, ograniczeń lokalizacyjnych oraz dopuszczalnych wartości parametrów geometrycznych i inematycznych. Jakiekolwiek zmiany tych ostatnich wpływają bezpośrednio na obliczenie elementarnych...
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Computing algebraic transfer entropy and coupling directions via transcripts
PublicationMost random processes studied in nonlinear time series analysis take values on sets endowed with a group structure, e.g., the real and rational numbers, and the integers. This fact allows to associate with each pair of group elements a third element, called their transcript, which is defined as the product of the second element in the pair times the first one. The transfer entropy of two such processes is called algebraic transfer...
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Spectrum-based modal parameters identification with Particle Swarm Optimization
PublicationThe paper presents the new method of the natural frequencies and damping identification based on the Artificial Intelligence (AI) Particle Swarm Optimization (PSO) algorithm. The identification is performed in the frequency domain. The algorithm performs two PSO-based steps and introduces some modifications in order to achieve quick convergence and low estimation error of the identified parameters’ values for multi-mode systems....
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A new approach to determination of the two-mass model parameters of railway current collector
PublicationThe paper presents two mathematical models of railway current collectors both with two degrees of freedom. The first one, hereinafter Pantograph Articulated Model (PAM), has one degree of freedom in rotational motion and the second degree of freedom in translational motion. The second model, called henceforth as Pantograph Reference Model (PRM), has both degrees of freedom in translational motion. Differential equations of the...
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A new approach to determination of the two-mass model parameters of railway current collector
PublicationThe paper presents two mathematical models of railway current collectors both with two degrees of freedom. The first one, hereinafter Pantograph Articulated Model (PAM), has one degree of freedom in rotational motion and the second degree of freedom in translational motion. The second model, called henceforth as Pantograph Reference Model (PRM), has both degrees of freedom in translational motion. Differential equations of the...
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Characterization of the Functionally Graded Shear Modulus of a Half-Space
PublicationIn this article, a method is proposed for determining parameters of the exponentialy varying shear modulus of a functionally graded half-space. The method is based on the analytical solution of the problem of pure shear of an elastic functionally graded half-space by a strip punch. The half-space has the depth-wise exponential variation of its shear modulus, whose parameters are to be determined. The problem is reduced to an integral...
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Correlations between organic pollution indicators in municipal wastewater
PublicationThe paper presents the results of a study of parameters used for determining the amount of organic pollutants in wastewater flowing into a collective wastewater treatment plant with a population equivalent of about 120 000 PE. The plant constituted part of a sewage system. Assays were performed for biochemical oxygen demand (BOD5), chemical oxygen demand (CODCr), permanganete index (CODMn) and total organic carbon (TOC). In addition,...
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Ionic thermoelectric effect in Cu2-δSe during phase transition
PublicationThe ionic Seebeck coefficient was studied in copper selenide with Cu1.99Se, Cu1.95Se and Cu1.8Se stoichiometry which was synthesized with a melt crystallization method. To measure the ionic Seebeck coefficient of copper ions, 0.15C6H12N4CH3I + 0.85CuI solid-state electrolyte was prepared. Electrolyte layers were pressed with copper selenide powder into a sandwich-like structure. At the temperature of 410 K, the materials have ionic...
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Prediction of Pile Shaft Capacity in Tension Based on Some Direct CPT Methods—Vistula Marshland Test Site
PublicationThis 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 diameter 0.4 m and the length varied from 8 m to 14.6 m were subjected to static load tests in tension. Their...
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A Diagnostic Method Based on Deflection Analysis for Monitoring Post-elastic Response of Beams
PublicationA non-destructive diagnostic method based on deflection analysis for monitoring the post-elastic response of beams was developed, and a diagnostic indicator was proposed. The indicator was defined as the second moment of the normalised curvature function about the mid-span, where the curvature was computed from the normalised deflection function. Elastic reference values of the indicator were computed for simply supported beams...
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Cyclic behaviour modelling of additively manufactured Ti-6Al-4V lattice structures
PublicationThe present work is concerned with the numerical modelling of the cyclic behaviour of Ti-6Al-4V lattice structures. In the study, diamond structures of titanium alloy produced by the additive laser powder bed fusion (LPBF) method with different degrees of relative density were used. Realistic geometric models of the studied mesostructures were generated using computed microtomography, taking into account the imperfections of the...
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Can sodium 1-alkylsulfonates participate in the sodium dodecyl sulfate micelle formation?
PublicationThe aggregation behavior of sodium dodecyl sulfate (SDS) was studied in an aqueous solution in the presence of increasing concentrations of selected sodium 1-alkylsulfonates, namely sodium 1-octanesulfonate, sodium 1-decanesulfonate, and sodium 1-dodecanesufonate. The critical micelle concentration (CMC) of SDS was determined by conductivity and fluorescence intensity measurements. The steady-state fluorescence quenching experiments...
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Leaf wettability and plant surface water storage for common wetland species of the Biebrza peatlands (northeast Poland)
PublicationWetlands play a crucial role in buffering the effects of climate change. At the same time, they are one of the most endangered ecosystems on the globe. The knowledge of the water cycle and energy exchange is crucial for the practical preservation and exploiting their capabilities. Leaf wettability is an important parameter characterising the plant's ability to retain water on its surface, and is linked to the ecosystems' hydrological...
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Empirical Relationship Describing Total Convective and Radiative Heat Loss in Buildings
PublicationOn the basis of theoretical considerations of convective-radiative heat transfer, a relationship was developed enabling the total convective and radiative heat flux QC+R emitted from any object at tw and its surroundings at t∞ to be calculated from known values of the surface temperature of such an object, i.e., the known temperature difference Δt=tw - t∞ and average air temperature Tav. This relationship is applied to thermal...
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Architektoniczne przestrzenie wspólne dizajnu i sztuki
PublicationW aspekcie współczesnego wszechobecnego konsumpcjonizmu i ograniczonych możliwości dotarcia do odbiorcy, role obiektów należących do sztuk czystych przejmują obiekty będące wytworami projektantów w zakresie sztuk użytkowych, w tym architektów. Jednocześnie sztuka poszukuje nowych form i środków wyrazu, żeby wzbudzić zainteresowanie. Rozpatrywanym obiektem jest Dom. Oczywistą jego odsłoną jest spełnienie oczekiwanej funkcji wynikającej...
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Eksperymentalne i numeryczne badania parametrów dynamicznych trybuny stalowej
PublicationTrybuny stalowe to konstrukcje, które odnajdują swoje zastosowanie głównie podczas wydarzeń sportowych, koncertów muzycznych oraz innych wydarzeń, którym towarzyszą rytmiczne aktywności widzów i głośna muzyka. Ze względu na smukłość oraz lekkość elementów z jakich wykonana jest konstrukcja trybuny jest ona bardzo łatwo wzbudzana przez ludzi do drgań. Z przeprowadzonej w pracy [4] analizy modalnej wynika, że masa ludzi prowadzi...
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Dynamiczne wyznaczanie parametrów elektrycznego obwodu szeregowego
PublicationPo załączeniu napięcia na skutek istnienia inercji prąd w obwodzie zaczyna narastać od wartości zerowej do znamionowej. W tym czasie narastają spadki napięć na rezystancjach (impedancjach obwodu) do chwili spełnienia prawa Kirchhoffa. Można utworzyć układ ze sprzężeniem zwrotnym (układ regulacji stałowartościowej bądź nadążnej), który poszukuje parametrów obwodu spełniających prawa Kirchhoffa – elementy nie muszą być liniowe. W...
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Application of PL-Grid Platform for Modeling of the Selected Acoustic Phenomena
PublicationDomain grids are specific computational environments, developed within the PLGrid Plus project. For the Acoustic domain grid two supercomputer grid based services were prepared. Dedicated software consists of the outdoor sound propagation module and psychoacoustical noise dosimeter. The results are presented in a form of maps of sound level and Temporary Threshold Shift (TTS) values, therefore the services may play an informative...