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Report no WOiO/II/67/2015 - Expertise about load capacity of twistlock foundation and sliding foundation
PublicationCustomer delivered to Laboratory 17 elements - twist lock foundations and sliding lock foundations (ship equipment for container lashing). Elements were selected from production series. Each element was loaded for braking load. After test visual inspection had been performed. The expertise contains: description of tested elements, test assumptions, test stand, results and conclusions
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Modeling and Strength Calculations of Parts Made Using 3D Printing Technology and Mounted in a Custom-Made Lower Limb Exoskeleton
PublicationThis study is focused on the application of 3D-printed elements and conventional elements to create a prototype of a custom-made exoskeleton for lower limb rehabilitation. The 3D-printed elements were produced by using Fused Deposition Modeling technology and acrylonitrile butadiene styrene (ABS) material. The scope of this work involved the design and construction of an exoskeleton, experimental testing of the ABS material and...
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Collision-Free Network Exploration
PublicationA set of mobile agents is placed at different nodes of a n-node network. The agents synchronously move along the network edges in a collision-free way, i.e., in no round may two agents occupy the same node. In each round, an agent may choose to stay at its currently occupied node or to move to one of its neighbors. An agent has no knowledge of the number and initial positions of other agents. We are looking for the shortest possible...
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Investigation into MPI All-Reduce Performance in a Distributed Cluster with Consideration of Imbalanced Process Arrival Patterns
PublicationThe paper presents an evaluation of all-reduce collective MPI algorithms for an environment based on a geographically-distributed compute cluster. The testbed was split into two sites: CI TASK in Gdansk University of Technology and ICM in University of Warsaw, located about 300 km from each other, both connected by a fast optical fiber Ethernet-based 100 Gbps network (900 km part of the PIONIER backbone). Each site hosted a set...
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Cast iron in the 19th-century building equipment
PublicationCast iron is a material, characteristics of which enable to receive extremely artistic elements. It maintains good strength properties at the same time. That combination of these seemingly contrary traits makes it a commodity that was widely used in the 19th century industry and architecture. These usages were not only as decorative elements, technical and structural ones. The production of new household utilities started, which...
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Linking of adjacent three-storey buildings for mitigation of structural pounding during earthquakes
PublicationThe reports after major earthquakes indicate that the earthquake-induced pounding between insufficiently separated buildings may lead to significant damage or even total collapse of structures. An intensive study has recently been carried out on mitigation of pounding hazards so as to minimize the structural damages or prevent collisions at all. The aim of this paper is to investigate the effectiveness of the method when two adjacent...
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On the Agile Mindset of an Effective Team – An Industrial Opinion Survey
PublicationIn this paper we present the results of an opinion survey among 52 agile practitioners who evaluated the importance of 26 selected elements of the agile mindset to the effectiveness of an agile team. In total, we have identified 70 unique agile mindset elements based on 11 literature sources and 5 interviews with industry experts. 7 elements belonged to the “support for business goals” category, 20 to the “relationships within...
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THE CONCEPT OF MODELING OF SNOW IMPACT ON THE STRUCTURE OF THE SUSPENDED TAURON ARENA ROOF IN CRACOW
PublicationThe article presents studies and numerical simulations on modeling snow influence on TAURON ARENA suspended roof structure in Cracow. The scope of work includes experimental tests, functions solutions taking into account various cases of snow impact according to PN and EC, as well as numerical simulations for the sport and entertainment arena in the Czyzyny district. The FEM roof structure model developed in the SOFISITK software...
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The interaction between bacterial abundance and selected pollutants concentration levels in an arctic catchment (southwest Spitsbergen, Svalbard)
PublicationPersistent organic pollutants (POPs) have been a topic of interest in environmental sciences for > 60 years. POPs in the Arctic have been investigated since the 1970s, when first atmospheric measurements revealed the presence of these pollutants in the polar regions. Major contaminant transport routes to the Arctic include atmospheric and oceanic transport, as well as inflow from rivers and sea ice. The sources of pollutants, such...
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Pounding mitigation of a short-span cable-stayed bridge using a new hybrid passive control system
PublicationThis paper investigates the effectiveness of a new hybrid passive control system on the seismic response of an existing steel cable-stayed bridge considering the pounding effect. The proposed hybrid passive control system comprises a seismic isolator and a metallic damper. The bridge is located in a high seismic zone and has suffered several damages including the earthquake-induced pounding damage during the 1988 earthquake....
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Wave propagation in plate structures for crack detection
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Numerical analysis of elastic wave propagation in unbounded structures
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Wave propagation in plate structures for crack detection.
PublicationW pracy przedstawiono analizę propagacji fali poprzecznej w płycie z pęknięciem. Do modelowania zagadnienia zastosowano metodę elementów spektralnych.
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Propagation of in-plane waves in an isotropic panel with a crack
PublicationW pracy przedstawiono model tarczowego elementu spektralnego do analizy propagacji fali wzdłuznej w panelach z uszkodzeniami.
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A higher order transversely deformable shell-type spectral finite element for dynamic analysis of isotropic structures
PublicationThis paper deals with certain aspects related to the dynamic behaviour of isotropic shell-like structures analysed by the use of a higher order transversely deformable shell-type spectral finite element newly formulated and the approach known as the Time-domain Spectral Finite Element Method (TD-SFEM). Although recently this spectral approach is reported in the literature as a very powerful numerical tool used to solve various...
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Certain numerical issues of wave propagation modelling in rods by the Spectral Finite Element Method
PublicationW pracy omówiony zagadnienia związane z modelowaniem propagacji fal sprężystych metodą Spektralnych Elementów Skończonych. Przedstawiono wpływ postaci macierzy mas na błędy rozwiązania. Omówiono zakres stosowalności modeli.
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Numerical analysis of elastic wave propagation in unbounded structures
PublicationThe main objective of this paper is to show the effectiveness and usefulness of the concept of an absorbing layer with increasing damping (ALID) in numerical investigations of elastic wave propagation in unbounded engineering structures. This has been achieved by the authors by a careful investigation of three different types of structures characterised by gradually increasing geometrical and mathematical description complexities....
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An optimal form of the finite element mass matrix in the analysis of longitudinal vibrations of rods
PublicationIn this paper, an attempt is made to find the optimal form of the mass matrix of a rod finite element, which allows one to obtain the smallest errors in the longitudinal frequency determination of natural vibrations of any boundary conditions within the whole range of determined frequencies. It is assumed that the mass matrix can be treated as a linear combination of the consistent and diagonal matrices. Based on analytical considerations,...
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Numerical analysis of size effect in RC beams scaled along height or length using elasto-plastic-damage model enhanced by non-local softening.
PublicationArtykuł omawia wyniki numeryczne dotyczące efektu skali w belkach żelbetowych uzyskane stosując metodę elementów skończonych. Dwuwymiarowe obliczenia wykonano dla belek żelbetowych podczas 4-punktowego zginania. Belki były skalowane wzdłuż wysokości lub długości. Beton został opisany prawem sprężysto-plastycznym z degradacją sztywności, rozszerzonym o nielokalność w osłabieniu. Wyniki numeryczne zostały porównane z wynikami doświadczalnymi....
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FE analysis of reinforced concrete corbels with enhanced continuum models
PublicationW artykule pokazano wyniki MES symulacji wsporników żelbetowych. Zachowanie wsporników modelowano przy zastosowaniu 3 różnych modeli betonu: sprężysto-plastycznego, degradacji sprężystej i rozmytych rys. Modele rozszerzono o długość mikrostruktury przy zastosowaniu teorii nielokalnej. Wyniki numeryczne porównano z doświadczeniami z literatury.
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A coupled constitutive model for fracture in plain concrete based on continuum theory with non-local softening and eXtended Finite Element Method
PublicationThe paper presents a constitutive model for concrete which combines a continuous and discontinuous fracture description. In a continuum regime, two different constitutive laws were used. First, a plasticity model with a Rankine failure criterion and an associated fl ow rule was used. Second, a constitutive law based on isotropic damage mechanics was formulated. In order to capture the width of a localized zone and to obtain mesh-independent...
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FE analysis of size effects in reinforced concrete beams without shear reinforcement based on stochastic elasto-plasticity with non-local softening.
PublicationW artykule przedstawiono wyniki analizy MES dotyczącej deterministycznego i statystycznego efektu skali w żelbetowych belkach bez zbrojenia na ścinanie. W analizie zastosowano prawo sprężysto-plastyczne z nielokalnym osłabieniem. Wyniki analizy porównano z doświadczeniami i modelem skali Bazanta.
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Environmental Role of Rime Chemistry at Selected Mountain Sites in Poland
PublicationThe results of field experiments on fog pollutantdeposition enhanced by local mountain climate, completed by thedendrochronological analysis of the forest response, are presentedin this paper. In spite of their low absolute altitude (1,000-1,600 ma.s.l), the Sudetes and the Silesian Beskid form a noticeable orographicbarrier for the airflow of the humid Atlantic air masses.This results in the increase of cloudiness and fog frequency...
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Structural properties of hypothetical CeBa2Cu3O7 compound from LSDA+DMFT calculations
PublicationThe hypothetical stoichiometric CeBa2Cu3O7 (Ce123) compound, which has not been synthesized as a single phase yet, was studied by the density functional theory (DFT). We utilized a method which merges the local spin density approximation (LSDA) with the dynamical mean-field theory (DMFT) to account for the electronic correlations. The LSDA+DMFT calculations were performed in the high-temperature range. The particular emphasis was...
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Investigation of continuous wave jamming in an IEEE 802.15.4 network
PublicationThis paper presents how continuous wave jamming affects IEEE 802.15.4 network. To this end, an office-based measurement setup has been proposed. Within the measurement area, 25 nodes have been set up in order to create a IEEE 802.15.4 tree-based test network structure. A dedicated jamming device that generates and transmits a continuous wave signal has been developed. Several tests have been conducted and presented to demonstrate...
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TWORZENIE MAP SIECI KOMPUTEROWYCH Z WYKORZYSTANIEM PROTOKOŁÓW TYPU LLDP
PublicationDla administratorów systemów sieciowych niezwykle istot-nym jest posiadanie narzędzia tworzącego dynamicznie mapę sieci do celów zarządzania, diagnostyki, zapobiegania awariom i włamaniom. Artykuł prezentuje protokoły wspierające tworzenie map sieci a także własne badania nad usprawnieniem istniejących algorytmów. Proponowane rozwiązania to: budowa map z użyciem protokołu LLDP i SNMP, odkrywanie wąskich gardeł w sieciach dzięki...
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Generalized regression neural network and fitness dependent optimization: Application to energy harvesting of centralized TEG systems
PublicationThe thermoelectric generator (TEG) system has attracted extensive attention because of its applications in centralized solar heat utilization and recoverable heat energy. The operating efficiency of the TEG system is highly affected by operating conditions. In a series-parallel structure, due to diverse temperature differences, the TEG modules show non-linear performance. Due to the non-uniform temperature distribution (NUTD) condition,...
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Quantitative assessment
PublicationThe main trends in the development of analytical chemistry are the determination of increasingly lower concentrations of analytes in samples with complex matrix composition (trace analysis). While the obtained analytical results must be reliable, which means that they must accurately (truly and precisely) reflect the actual content of analytes in a representative sample of the material object under study. However, it is an extremely...
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Vehicle classification based on soft computing algorithms
PublicationExperiments and results regarding vehicle type classification are presented. Three classes of vehicles are recognized: sedans, vans and trucks. The system uses a non-calibrated traffic camera, therefore no direct vehicle dimensions are used. Various vehicle descriptors are tested, including those based on vehicle mask only and those based on vehicle images. The latter ones employ Speeded Up Robust Features (SURF) and gradient images...
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A graph coloring approach to scheduling of multiprocessor tasks on dedicated machines with availability constraints
PublicationWe address a generalization of the classical 1- and 2-processor unit execution time scheduling problem on dedicated machines. In our chromatic model of scheduling machines have non-simultaneous availability times and tasks have arbitrary release times and due dates. Also, the versatility of our approach makes it possible to generalize all known classical criteria of optimality. Under these stipulations we show that the problem...
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Comparing phylogenetic trees using a minimum weight perfect matching
PublicationA phylogenetic tree represents historical evolutionary relationshipbetween different species or organisms. There are various methods for reconstructing phylogenetic trees.Applying those techniques usually results in different treesfor the same input data. An important problem is to determinehow distant two trees reconstructed in such a wayare from each other. Comparing phylogenetic trees is alsouseful in mining phylogenetic information...
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Improving all-reduce collective operations for imbalanced process arrival patterns
PublicationTwo new algorithms for the all-reduce operation optimized for imbalanced process arrival patterns (PAPs) are presented: (1) sorted linear tree, (2) pre-reduced ring as well as a new way of online PAP detection, including process arrival time estimations, and their distribution between cooperating processes was introduced. The idea, pseudo-code, implementation details, benchmark for performance evaluation and a real case example...
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The Snow Team Problem
PublicationWe study several problems of clearing subgraphs by mobile agents in digraphs. The agents can move only along directed walks of a digraph and, depending on the variant, their initial positions may be pre-specified. In general, for a given subset~$\cS$ of vertices of a digraph $D$ and a positive integer $k$, the objective is to determine whether there is a subgraph $H=(\cV_H,\cA_H)$ of $D$ such that (a) $\cS \subseteq \cV_H$, (b)...
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Weighted 2-sections and hypergraph reconstruction
PublicationIn the paper we introduce the notion of weighted 2-sections of hypergraphs with integer weights and study the following hypergraph reconstruction problems: (1) Given a weighted graph , is there a hypergraph H such that is its weighted 2-section? (2) Given a weighted 2-section , find a hypergraph H such that is its weighted 2-section. We show that (1) is NP-hard even if G is a complete graph or integer weights w does not exceed...
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The impact of training and neurotrophins on functional recovery after spinal cord transection: cellular and molecular mechanisms contributing to motor improvement
PublicationBeneficial effects of locomotor training on the functional recovery after complete transection of the spinal cord indicate that in chronic spinal animals spontaneous recovery processes are enhanced and shaped by the training. The mechanisms of that use-dependent improvement are still not fully understood. This review tackles three aspects of this issue: (1) neurochemical attributes of functional improvement...
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Partially prestressed concrete beams with bonded and unbonded strands
PublicationThis article relate the tests of partially prestressed concrete beams. There is presented the research programme - geometry of elements, method of loading, the materials and variables. There have been shown preliminary test results of prestressed concrete elements with bonded and unbonded strands, and compared to the test results of R.C. beam.
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A large family of filled skutterudites stabilized by electron count
PublicationThe Zintl concept is important in solid-state chemistry to explain how some compounds that combine electropositive and main group elements can be stable at formulas that at their simplest level do not make any sense. The electronegative elements in such compounds form a polyatomic electron-accepting molecule inside the solid, a ‘polyanion’, that fills its available energy states with electrons from the electropositive elements...
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RESIDUE ANALYSIS OF ETU AND PTU BY LC/MS
PublicationDithiocarbamates (DTCs) are important organosulfur compounds, which act as inhibitors of metal dependant and sulphydryl enzymes and have a serious consequence on biological systems. They possess variety of applications in agriculture as fungicides, as well as, in the rubber industry as vulcanization accelerators and antioxidants. In this way, DTCs are the main group of fungicides used to control approximately 400 pathogens of more...
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The Influence of Shear Deformation in analysis of plane frames
PublicationThe focus of the paper is to investigate the influence of shear deformation effect on the distribution of internal forces and frame deformation. To estimate shear deformation effect, the Timoshenko beam theory and the concept of shear deformation coefficients are used. Analysis of example frames gives the possibility to evaluate what have the most impact on size of shear deformation and in which type of frames the shear deformation...
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Empirically adjusted and consistent set of EHT valence orbital parametersfor all elements of the periodic table. Modelling Simul. Mater. Sci. Eng. [online]. 2004 vol. 12 [dostęp..] s. 21-32, 3 rys. 3 tab. bibliogr. 35 poz. Dostępny w Internecie stacks.iop.org/MSMSE/12/21.ISSN 0965-0393 Jednorodny skorygowany empirycznie zbiór parametrów EHT dla orbitali walen- cyjnych pierwiastków.
PublicationModel atomu HFS został zmodyfikowany poprzez przypisanie każdemu z atomówindywidualnego parametru ŕ. Wartości ŕ dobrano w oparciu o pierwszy poten-cjał jonizacji atomu. Parametry EHT wyznaczono w oparciu o tak zmodyfikowa-ny model HFS.
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New data acquisition system for birch sap concentrate production using the reverse osmosis technology
PublicationThe work presents a simple electronic device that helps to monitor the basic parameters of the reverse osmosis (RO) system during the concentration of birch tree sap. The construction costs are low (around 150 Euro) but the functionality of the device is high. It has an in-build two channel conductometer and can measure the volumetric flow rate of two streams of liquids. The collected data are transmitted wirelessly via Bluetooth...
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Limiting distribution of Lempel Ziv'78 redundancy
PublicationWe show that the Lempel Ziv'78 redundancy rate tends to a Gaussian distribution for memoryless sources. We accomplish it by extending findings from our 1995 paper [3]. We present a new simplified proof of the Central Limit Theorem for the number of phrases in the LZ'78 algorithm. As in our 1995 paper, here we first analyze the asymptotic behavior of the total path length in a digital search tree (a DST) built from independent sequences....
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On the Limiting distribution of Lempel Ziv'78 Redundancy for Memoryles Sources
PublicationWe show that the Lempel Ziv'78 redundancy rate tends to a Gaussian distribution for memoryless sources. We accomplish it by extending findings from our 1995 paper [3]. We present a new simplified proof of the Central Limit Theorem for the number of phrases in the LZ'78 algorithm. As in our 1995 paper, here we first analyze the asymptotic behavior of the total path length in a digital search tree (a DST) built from independent sequences....
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Treated wasetewater as a source of humic substances in surface waters
PublicationHumic substances impose substantial effect on the aquatic environment as well as the water organisms and human health. Among other features, the humic acids determine organoleptic properties of surface waters. Therefore explanation of the origin and properties of humic acids in surface waters is one of the priorities of water technology.Recently it was pointed out that in the wastewater treatment process organic compounds characterized...
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Water chemistry of tundra lakes in the periglacial zone of the Bellsund Fiord (Svalbard) in the summer of 2013
PublicationClimate changes observed in the Arctic (e.g. permafrost degradation, glacier retreat) may have significant influence on sensitive polar wetlands. The main objectives of this paper are defining chemical features of water within six small arctic lakes located in Bellsund (Svalbard) in the area of continuous permafrost occurrence. The unique environmental conditions of the study area offer an opportunity to observe phenomena influencing...
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Multifrequency Wideband Sonar Array
PublicationThis paper describes of new approach to Multifrequency Wideband Arrays (MWA),applied piezocomposite technologies of the array elements. MWA operating in transmitting(Tx) and receiving (Rx) mode on two or three bands, requires state-of-the-art technology andefficient array designing than conventional array in which separate arrays for every band oreven separate Tx and Rx transducers/arrays are used. The new piezocomposite elements...
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Identification of the Agile Mindset and Its Comparison to the Competencies of Selected Agile Roles
PublicationIn this paper we present the results of the identification and evalua-tion of the elements of an agile mindset as well as its comparison to the compe-tence models for the roles of Scrum Master, Product Owner and agile analyst. We have identified 70 unique agile mindset elements from literature and 5 in-terviews with experts. Based on an opinion survey among 52 agile practitioners we evaluated the importance of 26 selected elements...
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The central server of the Border Guard's distributed multimedia system for monitoring and visualisation of ongoing and archival events
PublicationThe paper presents the architecture and functionalities of the central server (CENTER) of the distributed system for the Polish Border Guard (BG) for monitoring maritime areas. The overall system has been extended to incorporate, apart from map data, also different multimedia elements such as video from cameras or audio from telephone connections operated by BG units. This requires new system elements: Archive Servers for storing...
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Sprawiedliwość agrarna Thomasa Paine’a i narodziny dyskursu egalitarnego
PublicationThomas Paine napisał Sprawiedliwość agrarną we Francji w roku 1796 w szczycie posttermidoriańskiego zamętu, krótko po wprowadzeniu Konstytucji Roku III. W swoim ostatnim wielkim pamflecie domaga się opodatkowania wielkich właścicieli ziemskich i pomoc biednym oraz wywłaszczonym. Artykuł krótko omawia propozycję Paine i analizuje jego strukturę argumentacyjną. Stawiam w niej tezę, że Paine nie do końca świadomie przechodzi od dowodu...
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Adaptation of the arbitrary Lagrange–Euler approach to fluid–solid interaction on an example of high velocity flow over thin platelet
PublicationThe aim of this study is to analyse the behaviour of a thin plate with air flow velocities of 0.3–0.9 Ma. Data from the experiment and numerical tools were used for the analysis. For fluid–solid interaction calculations, the arbitrary Lagrange–Euler approach was used. The results of the measurements are twofold. The first one is the measurement of the flow before and after vibrating plate, i.e. pure flow plate, and the second consists...