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Sundials of St Mary’s Church in Gdańsk / Zegary słoneczne kościoła pw. Wniebowzięcia Najświętszej Panny Marii w Gdańsku
PublikacjaThe paper presents contemporary research evidence of form, function and history of the sundials of St Mary’s Church in Gdańsk. The discussed sundials are located on the southern wall of the church transept. The sundial, which is believed to be made by Lorenzo Zachau in 1533, is placed on the west side of the western window, at the edge of the wall. The face of this sundial is separated by a horizontal line into two parts. The upper...
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Testing of DES toxicity towards Candida subhashii
Dane BadawczeDataset presents results of testing toxicity of selected DES solutions in mineral salt medium towards Candida subhashii.
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Determination of changes in viscosity of chitosan cosmetic preparations depending on shear rate.
Dane BadawczeThe rheological characteristics of chitosan were made on the basis of a viscosity measurement using a Brookfield viscometer, using LV SC4 - 25 spindles and shear rates from 0.3 to 32 s-1 (Fig. 1). Chitosan solutions at 1% concentrations in acetic acid were prepared. The samples were subjected to storage tests.
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Comparison of Doppler Effect Estimation Methods for MFSK Transmission in Multipath Hydroacoustic Channel
PublikacjaUnderwater wireless communication remains a challenging topic, particularly for applications such as wreck penetration where multipath and Doppler effects are very intense. These effects are becoming even more difficult to mitigate for fast data transmission systems that utilize wideband signals. Due to the low propagation speed of acoustic wave in the water, there is a significant difference between the Doppler shift for lower...
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Stability by linear approximation for time scale dynamical systems
PublikacjaWe study systems on time scales that are generalizations of classical differential or difference equations and appear in numerical methods. In this paper we consider linear systems and their small nonlinear perturbations. In terms of time scales and of eigenvalues of matrices we formulate conditions, sufficient for stability by linear approximation. For non-periodic time scales we use techniques of central upper Lyapunov exponents...
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Maxillary sinus aeration analysis using computational fluid dynamics
PublikacjaThe maxillary sinus aeration using the computational fluid dynamics (CFD) method based on individual adult patients’ computed tomography (CT) scans were analyzed. The analysis was based on CT images of 4 patients: one with normal nose anatomy and three with nasal septal deviation (NSD) and concha bullosa (CB). The CFD simulation was performed using the Reynolds-Average Simulation approach and turbulence closure based on linear...
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The effect of paleo-environment on hydrocarbon generation potential: Example from Vaca Muerta Formation, Neuquén Basin, Argentina
PublikacjaA 137-m continuous core from the Jurassic-Early Cretaceous marine derived oil shale with the maturity Ro about 0.7 %, representing the oil window in the Vaca Muerta Formation, Neuquén Basin, Argentina, was examined using geological, mineralogical, petrographic, and geochemistry techniques. Three distinct intervals were identified within the core: the upper carbonate-rich section with intense bioturbation, indicating dysoxic to...
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On Design Optimization of Miniaturized Microscrip Dual-Band Rat-Race Coupler with Enhanced Bandwidth
PublikacjaIn the paper, a novel topology of a miniaturized wideband dual-band rat-race coupler has been presented. Small size of the circuit has been obtained by meandering transmission lines of the conventional circuit. At the same time, the number of independent geometry parameters has been increased in order to secure sufficient circuit flexibility in the context of its design optimization for dual-band operation. Optimum dimensions of...
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Fast simulation-driven design optimization of UWB band-notch antennas
PublikacjaIn this letter, a simple yet reliable and automated methodology for rapid design optimization of ultra-wideband (UWB) band-notch antennas is presented. Our approach is a two-stage procedure with the first stage focused on the design of the antenna itself, and the secondstage aiming at identification of the appropriate dimensions of the resonator with the purpose of allocating the band-notch in the desired frequency range. For the...
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Graphs with equal domination and certified domination numbers
PublikacjaA setDof vertices of a graphG= (VG,EG) is a dominating set ofGif every vertexinVG−Dis adjacent to at least one vertex inD. The domination number (upper dominationnumber, respectively) ofG, denoted byγ(G) (Γ(G), respectively), is the cardinality ofa smallest (largest minimal, respectively) dominating set ofG. A subsetD⊆VGis calleda certified dominating set ofGifDis a dominating set ofGand every vertex inDhas eitherzero...
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A High-Arctic flow-through lake system hydrochemical changes: Revvatnet, southwestern Svalbard (years 2010–2018)
PublikacjaLake ecosystems are strongly coupled to features of their surrounding landscapes such as geomorphology, lithology, vegetation and hydrological characteristics. In the 2010–2018 summer seasons, we investigated an Arctic flow-through lake system Revvatnet, located in the vicinity of the coastal zone of Hornsund fjord in Svalbard, characterising its hydrological properties and the chemical composition of its waters. The lake system...
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The influence of frequency separation on imaging properties in DFEIT
PublikacjaW artykule przedstawiono wpływ wyboru składowych częstotliwościowych dla różnicowej tomografii impedancyjnej na wynik i własności obrazowania w dwuczęstotliwościowej różnicowej tomografii impedancyjnej.A Dual Frequency EIT is an extension of a traditional EIT that uses two sinusoidal signals for imaging. Appropriate selection of signals' frequency allows to achieve reasonable contrast of imaged structure. It has already been shown...
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Hierarchical dissolved oxygen control for activated sludge processes
PublikacjaA hierarchical controller for tracking the dissolved oxygen reference trajectory in activated sludge processes is proposed and investigated. The removal of nitrogen and phosphorous from wastewater is considered. Typically, an aeration system itself is a complicated hybrid nonlinear dynamical system with faster dynamics compared to the internal dynamics of the dissolved oxygen in a biological reactor. It is a common approach to...
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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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Collision-free network exploration
PublikacjaMobile agents start at different nodes of an n-node network. The agents synchronously move along the network edges in a collision-free way, i.e., in no round two agents may occupy the same node. An agent has no knowledge of the number and initial positions of other agents. We are looking for the shortest time required to reach a configuration in which each agent has visited all nodes and returned to its starting location. In...
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Zero-range potentials for Dirac particles: Bound-state problems
PublikacjaA model in which a massive Dirac particle in $\mathbb{R}^{3}$ is bound by $N\geqslant1$ spatially distributed zero-range potentials is presented. Interactions between the particle and the potentials are modeled by subjecting a particle's bispinor wave function to certain limiting conditions at the potential centers. Each of these conditions is parametrized by a $2\times2$ Hermitian matrix (or, equivalently, a real scalar and a...
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The effect of raw material type on endotoxin content .
Dane BadawczeThe datasets contain the results of determining the effect of raw material type on endotoxin content as well as the effect of purification methods. The endotoxin concentration was determined using the PyroGene Recombinant Factor C Endpoint Fluorescent Assay. Beckmann-Kenko sodium alginate and Chemat sodium salt of alginic acid were used for the assays....
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Elemental composition, environment of deposition of the Lower Carboniferous Emma Fiord Formation oil shale in Arctic Canada
PublikacjaThe sedimentary succession of 51-m consisting of a thin coal seam (1 m) and oil shale with a marlstone and carbonate-mudstone matrix of the Lower Carboniferous (Viséan) Emma Fiord Formation located on the Grinnell Peninsula, Devon Island, Arctic Canada was examined. The techniques used include reflected light microscopy, and instrumental neutron activation analysis (INAA) for elemental concentration, and inductively coupled plasma...
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Degradation of stiffness of building columns exposed to bending and impact load during ground motions
PublikacjaThe safety of civil engineering structures under external loads, including ground motions, is one of the issues related to the idea of sustainable society. The earthquake-induced soft-storey failure is a typical type of damage observed in buildings due to seismic excitation. The failure of an intermediate soft storey of a structure results in large vertical impact loading acting on the lower floors due to the fall of the upper...
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On some Zarankiewicz numbers and bipartite Ramsey Numbers for Quadrilateral
PublikacjaThe Zarankiewicz number z ( m, n ; s, t ) is the maximum number of edges in a subgraph of K m,n that does not contain K s,t as a subgraph. The bipartite Ramsey number b ( n 1 , · · · , n k ) is the least positive integer b such that any coloring of the edges of K b,b with k colors will result in a monochromatic copy of K n i ,n i in the i -th color, for some i , 1 ≤ i ≤ k . If n i = m for all i , then we denote this number by b k ( m )....
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Modeling of Ice Passage Through Reservoirs System on the Vistula River
PublikacjaNumerical model was used to assess ice passage through proposed reservoir on the lower Vistula River. Model results were compared with observation on the Vistula River, but because the dam is not constructed yet, the direct comparison was not possible. The study focused on ice movement and accumulation in the reservoir for variety of low flow condition with and without wind effect. Bridge’s piers in the upper part of the reservoir...
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EFFECT OF NANOFLUID CONCENTRATION ON TWO-PHASE THERMOSYPHON HEAT EXCHANGER PERFORMANCE
PublikacjaAn approach – relaying on application of nanofluid as a working fluid, to improve performance of the two-phase thermosyphon heat exchanger (TPTHEx) has been proposed. The prototype heat exchanger consists of two horizontal cylindrical vessels connected by two risers and a downcomer. Tube bundles placed in the lower and upper cylinders work as an evaporator and a condenser, respectively. Distilled water and nanofluid water-Al2O3...
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Design-Oriented Constrained Modeling of Antenna Structures
PublikacjaFast surrogate models are crucially important to reduce the cost of design process of antenna structures. Due to curse of dimensionality, standard (data-driven) modeling methods exhibit serious limitations concerning the number of independent geometry parameters that can be handled but also (and even more importantly) their parameter ranges. In this work, a design-oriented modeling framework is proposed in which the surrogate is...
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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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Refined theoretical study of radiative association: Cross sections and rate constants for the formation of SiN
PublikacjaRadiative association of silicon mononitride (SiN) in its two lowest molecular electronic states is studied through quantum and classical dynamics. Special attention is paid to the behavior of the cross section at high collision energies. A modified expression for the semiclassical cross section is presented which excludes transitions to continuum states. This gives improved agreement with quantum mechanical perturbation theory...
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A structure and design optimization of novel compact microscrip dual-band rat-race coupler with enhanced bandwidth
PublikacjaIn the letter, a topology of a novel compact wideband dual-band rat-race coupler has been presented along with its computationally efficient design optimization procedure. Reduction of the circuit size has been achieved by meandering transmission lines of the conventional circuit. At the same time, the number of independent geometry parameters has been increased so as to secure sufficient flexibility of the circuit, necessary in...
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Method for universal detection of two-photon polarization entanglement
PublikacjaDetecting and quantifying quantum entanglement of a given unknown state poses problems that are fundamentally important for quantum information processing. Surprisingly, no direct (i.e., without quantum tomography) universal experimental implementation of a necessary and sufficient test of entanglement has been designed even for a general two-qubit state. Here we propose an experimental method for detecting a collective universal...
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Frequency-Reconfigurable Hybrid SIW-Based Self-Diplexing Antenna Using Solid and Liquid Dielectric Loading
PublikacjaThis paper presents a novel frequencyreconfigurable self-diplexing antenna (SDA) utilizing a hybrid substrate-integrated waveguide (SIW). The antenna comprises a radiating slot, a feeding network, and a hybrid SIW cavity featuring half-mode circular and half-mode rectangular SIW structures. The unique feature of this antenna lies in its fine-tuning capability of each resonant frequency by inserting or injecting solid and liquid...
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Insightful studies of AuCu nanostructures deposited on Ti platform: Effect of rapid thermal annealing on photoelectrochemical activity supported by synchrotron radiation studies
PublikacjaIn this work, we present the influence of annealing atmospheres during rapid thermal annealing (40◦C/s) on nanostructured Ti platforms modified by 10 nm layer of AuCu alloy obtained via magnetron sputtering. The AuCu/Ti platform annealed under hydrogen atmosphere exhibits the best photoelectrochemical activity under visible light, i.e. 27 times higher photocurrent than for pure Ti dimpled platform, and the lowest reflectance with minimum...
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Experimental and numerical study on deformed steel columns subjected to impact load during earthquakes
PublikacjaThe soft-storey failure is one of the most typical types of damage observed in buildings during earthquakes. The failure of an upper soft storey of a structure results in large impact load acting on the lower floors and if the resistance of the structural members of the lower storeys is not sufficient it may further lead to progressive collapse of the whole building. The aim of the present paper is to investigate the dynamic behaviour...
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The viscometric evaluation of the gelation rate the chitosan-metal oxide hydrogel systems.
Dane BadawczeThe dataset shows the change in the viscosity of a hydrogel medium over time. Viscometric measurement was used as a universal method for determining the cross-linking rate of chitosan hydrogel using metal oxides or other solutions with a negative net charge. The method was prepared as a method of predicting the kinetics of additive manufacturing using...
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Experimental study on the behaviour of steel columns under seismic-induced axial impact load
PublikacjaIt has been observed during major earthquakes that the so called soft-storey failure of an upper floor of a structure results in large impact load acting on structural members of the lower storeys. It may further lead to progressive collapse of the whole structure substantially intensifying human and material losses. Therefore, the aim of this paper is to investigate experimentally the behaviour of columns under bending (observed...
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Levels of 13 multi-class pesticide residues in Polish honeys determined by LC-ESI-MS/MS
PublikacjaLevels of 13 pesticides in 40 honey samples form Poland are reported. A rapid and sensitive method was developed for the LC-ESI-MS/MS determination of multi-class pesticide residues in honey samples. Liquid-liquid extraction (LLE) on a diatomaceous earth support (requiring the use of small amounts of organic solvent), followed by chromatographic separation on a C18 column and gradient elution were employed. The method quantifies...
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Physical properties and electronic structure of La3Co and La3Ni intermetallic superconductors
PublikacjaLa3Co and La3Ni are reported superconductors with transition temperatures of 4.5 and 6 K, respectively. Here, we reinvestigate the physical properties of these two intermetallic compounds with magnetic susceptibility χ, specific heat Cp and electrical resistivity ρ measurements down to 1.9 K. Although bulk superconductivity is confirmed in La3Co, as observed previously, only a trace of it is found in La3Ni, indicating that the...
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Nonlinear finite element modeling of vibration control of plane rod-type structural members with integrated piezoelectric patches
PublikacjaThis paper addresses modeling and finite element analysis of the transient large-amplitude vibration response of thin rod-type structures (e.g., plane curved beams, arches, ring shells) and its control by integrated piezoelectric layers. A geometrically nonlinear finite beam element for the analysis of piezolaminated structures is developed that is based on the Bernoulli hypothesis and the assumptions of small strains and finite...
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Magneto-thermal convection of low concentration nanofluids
PublikacjaThe main aim of this paper was to analyze possible utilization of the low concentration nanofluids and the magnetic field to enhance heat transfer. The studied fluids were based on water with an addition of copper particles (40-60 nm diameter). They belonged to the diamagnetic group of materials. As a first attempt to stated target the analysis of enclosure placed in the maximal value of square magnetic induction gradient was carried...
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ECONOMIC GROWTH AND FEMALE LABOR FORCE PARTICIPATION – VERIFYING THE U-FEMINIZATION HYPOTHESIS. NEW EVIDENCE FOR 162 COUNTRIES OVER THE PERIOD 1990-2012.
PublikacjaThe paper contributes by providing new insights into relationship between female labor force and economic growth in 162 world countries over the period 1990-2012. It is anticipated uncovering U-shaped relationship between female labor force participation and economic growth. The analysis is run in two different perspectives – first the relationship is examined for sample encompassing 162 countries; and second – the evidence is...
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Bound on Bell inequalities by fraction of determinism and reverse triangle inequality
PublikacjaIt is an established fact that entanglement is a resource. Sharing an entangled state leads to nonlocal correlations and to violations of Bell inequalities. Such nonlocal correlations illustrate the advantage of quantum resources over classical resources. In this paper, we quantitatively study Bell inequalities with 2 × n inputs. As found in Gisin et al. [Int. J. Quantum. Inform. 05, 525 (2007)], quantum mechanical correlations...
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A Novel Coupling Matrix Synthesis Technique for Generalized Chebyshev Filters With Resonant Source–Load Connection
PublikacjaThis paper reports a novel synthesis method for microwave bandpass filters with resonant source–load connection. In effect, a network realizing N+1 transmission zeros (where N is the number of reflection zeros) is obtained. The method is based on a prototype transversal coupling matrix (N+2, N+2) with source and load connected by a resonant circuit formed by a capacitor in parallel with a frequency-invariant susceptance. To complement...
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Prediction of Wastewater Quality at a Wastewater Treatment Plant Inlet Using a System Based on Machine Learning Methods
PublikacjaOne of the important factors determining the biochemical processes in bioreactors is the quality of the wastewater inflow to the wastewater treatment plant (WWTP). Information on the quality of wastewater, sufficiently in advance, makes it possible to properly select bioreactor settings to obtain optimal process conditions. This paper presents the use of classification models to predict the variability of wastewater quality at...
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Anti-plane shear waves in an elastic strip rigidly attached to an elastic half-space
PublikacjaWe consider the anti-plane shear waves in a domain consisting of an infinite layer with a thin coating lying on an elastic half-space. The elastic properties of the coating, layer, and half-space are assumed to be different. On the free upper surface we assume the compatibility condition within the Gurtin–Murdoch surface elasticity, whereas at the plane interface we consider perfect contact. For this problem there exist two possible...
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Daytime Acute Non-Visual Alerting Response in Brain Activity Occurs as a Result of Short- and Long-Wavelengths of Light
PublikacjaVery recent preliminary findings concerning the alerting capacities of light stimulus with long-wavelengths suggest the existence of neural pathways other than melatonin suppression that trigger the nonvisual response. Though the nonvisual effects of light during the daytime have not been investigated thoroughly, they are definitely worth investigating. The purpose of the present study is to enrich existing evidence by describing...
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The influence of the type of composition of PVA-chitosan blends on stability at elevated temperature
Dane BadawczeThe dataset shows the results of a visual evaluation of chitosan and polyvinyl alcohol composites. The composites were prepared by combining chitosan water solutions, dissolved in selected acids, and polyvinyl alcohol solution, freeze drying, and heating at 150°C dry composites. The results confirm that the chitosan / PVA composites, in which the first...
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Platform Supporting the Esophageal Impedance Analysis
PublikacjaThe esophageal pH-impedance examination is one of the most popular diagnostic methods for identifying the upper gastrointestinal tract’s diseases. Inconclusive test evaluation criteria makes it difficult to state the definite diagnosis. In this paper, the computer platform supporting the research and teaching process in the area of pH-impedance analysis is presented. Users, having a variety of mathematical and statistical methods...
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An Application Supporting Gastroesophageal Multichannel Intraluminal Impedance-pH Analysis
PublikacjaDue to a significant rise in the number of patients diagnosed with diseases of the upper gastrointestinal tract and the high cost of treatment, there is a need to further research on one of the most popular diagnostic tests used in this case – esophageal Multichannel Intraluminal Impedance and pH measurement. This may lead to finding new diagnostically relevant information, used to quicken and improve the diagnostic procedure....
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Application in circular sawing machines of the experimental results of investigations of the chip removing system operation
PublikacjaThe experimental results of the chip removing system operation are presented. The main aim of them was to optimize suction system of the panel saw Fx3 and its follower Fx550. The attention was focused on the upper casing, which was the part of removing system. Within the framework of the work a systematic experimental study of pressure distribution in the casing during operation of the selected rotational speed of saw blade with...
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INVESTIGATION OF BOTTOM SEDIMENT STRATIFICATION
PublikacjaThe main goal of this paper is to find a method to assess remotely the type of sediments on the basis of the signal received using the parametric echosounder. The images of the sea bottom sediments taken by a parametric echosounder show the fine structure of the upper layer of the bottom sediments. The depth of penetration depends on the type of sediment, in fact on the attenuation of acoustic wave. In the paper the method of distinguishing...
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Posttraumatic Orbital Emphysema: A Numerical Model
PublikacjaOrbital emphysema is a common symptom accompanying orbital fracture. The pathomechanism is still not recognized and the usually assumed cause, elevated pressure in the upper airways connected with sneezing or coughing, does not always contribute to the occurrence of this type of fracture. Observations based on the finite model (simulating blowout type fracture) of the deformations of the inferior orbital wall after a strike in...
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Predicting seismic response of SMRFs founded on different soil types using machine learning techniques
PublikacjaPredicting the Maximum Interstory Drift Ratio (M-IDR) of Steel Moment-Resisting Frames (SMRFs) is a useful tool for designers to approximately evaluate the vulnerability of SMRFs. This study aims to explore supervised Machine Learning (ML) algorithms to build a surrogate prediction model for SMRFs to reduce the need for complex modeling. For this purpose, twenty well-known ML algorithms implemented in Python software are trained...
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Constructing a map of an anonymous graph: applications of universal sequences
PublikacjaWe study the problem of mapping an unknown environmentrepresented as an unlabelled undirected graph. A robot (or automaton)starting at a single vertex of the graph G has to traverse the graph and return to its starting point building a map of the graph in the process. We are interested in the cost of achieving this task (whenever possible) in terms of the number of edge traversal made by the robot. Another optimization criteria...