Filters
total: 802
filtered: 670
Search results for: RANDOM SUBSOIL
-
Evolving neural network as a decision support system — Controller for a game of “2048” case study
PublicationThe paper proposes an approach to designing the neuro-genetic self-learning decision support system. The system is based on neural networks being adaptively learned by evolutionary mechanism, forming an evolved neural network. Presented learning algorithm enables for a selection of the neural network structure by establishing or removing of connections between the neurons, and then for a finding the beast suited values of the network...
-
On reliability assessment of ship machinery system in different autonomy degree; A Bayesian-based approach
PublicationAnalyzing the reliability of autonomous ships has recently attracted attention mainly due to epistemic uncertainty (lack of knowledge) integrated with automatic operations in the maritime sector. The advent of new random failures with unrecognized failure patterns in autonomous ship operations requires a comprehensive reliability assessment specifically aiming at estimating the time in which the ship can be trusted to be left unattended....
-
Predictions of cervical cancer identification by photonic method combined with machine learning
PublicationCervical cancer is one of the most commonly appearing cancers, which early diagnosis is of greatest importance. Unfortunately, many diagnoses are based on subjective opinions of doctors—to date, there is no general measurement method with a calibrated standard. The problem can be solved with the measurement system being a fusion of an optoelectronic sensor and machine learning algorithm to provide reliable assistance for doctors...
-
Thermomagnetic behavior of a semiconductor material heated by pulsed excitation based on the fourth-order MGT photothermal model
PublicationThis article proposes a photothermal model to reveal the thermo-magneto-mechanical properties of semiconductor materials, including coupled diffusion equations for thermal conductivity, elasticity, and excess carrier density. The proposed model is developed to account for the optical heating that occurs through the semiconductor medium. The Moore–Gibson–Thompson (MGT) equation of the fourth-order serves as the theoretical framework...
-
Fracture Areas Quantitative Investigating of Bending-Torsion Fatigued Low-Alloy High-Strength Steel
PublicationIn this study, the impact of pseudo-random non-proportional bending-torsion fatigue loadings proportion on the fatigue life and the fracture surface topography was analyzed. Investigation was carried out for 24 specimens made of S355J2 steel with 11 different ratios of maximum stresses λ. For these cases, after the fatigue tests, the surface topography measurements were carried out using an optical profilometer, using the focus...
-
Integrated model for the fast assessment of flood volume: Modelling – management, uncertainty and sensitivity analysis
PublicationThe specific flood volume is an important criterion for assessing the performance of sewage networks. It has been shown that its value is greatly influenced by the layout of the sewers in the catchment area, which is usually expressed by a fractal dimension. Currently, only mechanistic models (such as SWMM) enable the determination of the impact of the layout of the sewers on flooding volume, but they require additional and robust...
-
Thermal, electrical, and magnetic properties of Fe2O3–PbO–SiO2 glass prepared by traditional melt-quenching and twin roller fast-cooling methods
PublicationIn this study, Fe–Pb–Si oxide glasses containing between 12.5 and 17.5 mol% Fe2O3 were prepared using two different methods comprising traditional melt-quenching and twin roller fast-cooling techniques. The topography and structure of the materials obtained were characterized by X-ray powder diffraction and scanning electron microscopy. All of the materials were found to be amorphous. The topography of most of the glasses comprised...
-
Emisyjność elektromagnetyczna przekształtników energoelektronicznych z modulacją rozproszoną
PublicationJednym z niepożądanych efektów ubocznych intensywnego rozwoju układów energoelektronicznych jest ich znaczna emisyjność elektromagnetyczna w zakresie zaburzeń przewodzonych i promieniowanych. Istnieje wiele metod ograniczania emisyjności tych układów, jednak ich skuteczność nie zawsze jest wystarczająca do spełnienia wymagań związanych z kompatybilnością elektromagnetyczna. W pracy zaprezentowano wyniki pomiarów skuteczności ograniczania...
-
Discrete element method simulations of fracture in concrete under uniaxial compression based on its real internal structure
PublicationThe paper describes experimental and numerical results of concrete fracture under quasi-static uniaxial compression. Experimental uniaxial compression tests were performed on concrete cubic specimens. Fracture in concrete was detected at the aggregate level by means of three non-destructive methods: three-dimensional X-ray microcomputed tomography, two-dimensional scanning electron microscope and manual two-dimensional digital...
-
Numerical analysis of pile installation effects in cohesive soils
PublicationIn this thesis the empirical equation for radial effective stress calculation after displacement pile installation and following consolidation phase has been proposed. The equation is based on the numerical studies performed with Updated Lagrangian, Arbitrary Lagrangian-Eulerian and Coupled Eulerian-Lagrangian formulations as well as the calibration procedure with database containing world-wide 30 pile static loading tests in cohesive...
-
Effect of Ethanol Extracts of Propolis (EEPs) against Staphylococcal Biofilm—Microscopic Studies
PublicationStaphylococci growing in the form of biofilm exhibit high resistance to a plethora of antibiotics. The aim of the study was to assess the influence of ethanolic extract of propolis (EEPs) on S. epidermidis ATCC 35984 biofilm using fluorescent microscopy. Propidium iodide (PI) and SYTO 9 were used for differentiation of live and dead cells, and calcofluor white was used to stain the extracellular matrix, the self-produced extracellular...
-
A New Metric for Long-Range Transport Potential of Chemicals
Publication -
Numerically efficient algorithm for compact microwave device optimization with flexible sensitivity updating scheme
PublicationAn efficient trust-region algorithm with flexible sensitivity updating management scheme for electromagnetic (EM)-driven design optimization of compact microwave components is proposed. During the optimization process, updating of selected columns of the circuit response Jacobian is performed using a rank-one Broyden formula (BF) replacing finite differentiation (FD). The FD update is omitted for directions sufficiently well aligned...
-
Problems of varistor quality assessment during exploitation
PublicationVaristors are commonly used elements which protect power supply networks against high-voltage surges or lightning. Therefore, quality and endurance of these elements is important to avoid losses when an expensive laboratory equipment would not be protected from random overvoltages. Additionally, excessive leakage currents generate serious costs due to high energy consumption. The paper presents shortly properties of varistors that...
-
A benchmark for particle shape dependence
PublicationParticle shape is a major parameter for the space-filling and strength properties of granular materials. For a systematic investigation of shape effect, a numerical benchmark test was set up within a collaborative group using different numerical methods and particles of various shape characteristics such as elongation, angularity and nonconvexity. Extensive 2D shear simulations were performed in this framework and the shear strength...
-
Particle shape dependence in 2D granular media
PublicationParticle shape is a key to the space-filling and strength properties of granular matter. We consider a shape parameter eta describing the degree of distortion from a perfectly spherical shape. Encompassing most specific shape characteristics such as elongation, angularity and non-convexity, eta is a low-order but generic parameter that we used in a numerical benchmark test for a systematic investigation of shape dependence in sheared...
-
Water-mediated influence of a crowded environment on internal vibrations of a protein molecule
PublicationThe influence of crowding on the protein inner dynamics is examined by putting a single protein molecule close to one or two neighboring protein molecules. The presence of additional molecules influences the amplitudes of protein fluctuations. Also, a weak dynamical coupling of collective velocities of surface atoms of proteins separated by a layer of water is detected. The possible mechanisms of these phenomena are described....
-
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...
-
A Parallel MPI I/O Solution Supported by Byte-addressable Non-volatile RAM Distributed Cache
PublicationWhile many scientific, large-scale applications are data-intensive, fast and efficient I/O operations have become of key importance for HPC environments. We propose an MPI I/O extension based on in-system distributed cache with data located in Non-volatile Random Access Memory (NVRAM) available in each cluster node. The presented architecture makes effective use of NVRAM properties such as persistence and byte-level access behind...
-
Controlling crystallites orientation and facet exposure for enhanced electrochemical properties of polycrystalline MoO3 films
PublicationThis study focuses on the development and optimization of MoO3 films on commercially available FTO substrates using the pulsed laser deposition (PLD) technique. By carefully selecting deposition conditions and implementing post-treatment procedures, precise control over crystallite orientation relative to the substrate is achieved. Deposition at 450 °C in O2 atmosphere results in random crystallite arrangement, while introducing...
-
Incorporating installation effects into the probability analysis of controlled modulus columns
PublicationThis technical report presents the probabilistic analysis which integrates the Monte Carlo simulation (MCS) with random field theory to model the load–displacement behavior of Controlled Modulus Columns (CMCs) in overconsolidated Poznań clay. Presented study focuses on the practical aspects of statistical analysis of geotechnical data, numerical model development, and results evaluation. Variability and spatial distribution of...
-
Reinforcement Learning Algorithm and FDTD-based Simulation Applied to Schroeder Diffuser Design Optimization
PublicationThe aim of this paper is to propose a novel approach to the algorithmic design of Schroeder acoustic diffusers employing a deep learning optimization algorithm and a fitness function based on a computer simulation of the propagation of acoustic waves. The deep learning method employed for the research is a deep policy gradient algorithm. It is used as a tool for carrying out a sequential optimization process the goal of which is...
-
Diagnostic Model of Crankshaft Seals
PublicationT he paper presents a research stand being a diagnostic model of radial lip seals used, among others, on crankshafts of piston combustion engines in order to identify the correctness of their operation. The possibility of determining the technical condition of lip seals on the basis of the proposed coefficient of correctness of operation has been described. T he basic features of seals influencing their correctness of...
-
PLC-based Implementation of Stochastic Optimization Method in the Form of Evolutionary Strategies for PID, LQR, and MPC Control
PublicationProgrammable logic controllers (PLCs) are usually equipped with only basic direct control algorithms like proportional-integral-derivative (PID). Modules included in engineering software running on a personal computer (PC) are usually used to tune controllers. In this article, an alternative approach is considered, i.e. the development of a stochastic optimizer based on the (μ,λ) evolution strategy (ES) in a PLC. For this purpose,...
-
Comparison of Two Methods for the Determination of Selected Pesticides in Honey and Honeybee Samples
PublicationDeveloped and validated analytical methods for the determination of a wide spectrum of pesticide residues in honey and honeybee samples after the modification of QuEChERS extraction in combination with gas chromatography–tandem quadrupole mass spectrometry (GC-MS/MS) and liquid chromatography–tandem quadrupole mass spectrometry (LC-MS/MS) were discussed and compared. The developed methods were evaluated regarding the utilized equipment...
-
Structural Health Monitoring System for Suspension Footbridge
PublicationThe article presents the structural health monitoring (SHM) system installed in a footbridge in Radom. The main reason for the need for fitting of such a system was failed acceptance tests of the bridge. While under a dynamic load consisting of a group of 12 pedestrians jumping on the bridge, the bridge developed vibration during which acceleration of the deck of up to 4.5 m/s2 was recorded. Such behavior of the footbridge causes...
-
Przemiany strukturalne i reforma systemu bankowego w Polsce
PublicationW pracy przedstawiono przemiany strukturalne w systemie bankowym w Polsce, jako element dostosowania się do wymogów stawianych przez Unię Europejską. Procesy systemowych i strukturalnych przekształceń w systemie bankowym rozpatrzono jako konieczność stworzenia bezpiecznego i efektywnego systemu bankowego, pozwalającego bankom komercyjnym na funkcjonowanie w warunkach konkurencji i ryzyka.
-
Funkcjonowanie rynku wierzytelności w Polsce - lata 1999-2001.
PublicationPraca przedstawia strukturę i działanie rynku nieruchomości w Polsce. Szczególną uwagę poświęcono instytucjom obsługującym obrót wierzytelnościami. Istotą tematu są wierzytelności przyporządkowane poszczególnym branżom i specyfika i ich powstawanie. Ważną rolę w handlu wierzytelnościami odgrywa prawo, które jest przedmiotem analiz w pracy. Nowym rozwiązaniem jest wykorzystanie internetu do handlu długami.
-
Exploring of electronic structure of nitrogen-modified TiO2 photocatalysts through photocurrent and surface photovoltage studies
PublicationPrzeprowadzono pomiary fotonapięcia powierzchniowego i fotoprądu w obecności różnych reduktorów celem otrzymania eksperymentalnego potwierdzenia położenia pasma walencyjnego w strukturze elektronowej tlenku tytanu(IV) modyfikowanego azotem. Zaobserwowano silne sprzężenie poziomów N 2p i O 2p, którego konsekwencją jest powstanie nowego pasma walencyjnego
-
Stability Assessment of Coastal Cliffs Incorporating Laser Scanning Technology and a Numerical Analysis
PublicationWe investigated the cli coast in Jastrzebia Gora, Poland. The measurements that were taken between 2014 and 2018 by applying terrestrial, mobile, and airborne laser scanning describe a huge geometric modification involving dislocations in a 2.5 m range. Dierential maps and a volumetric change analysis made it possible to identify the most deformed cli’s location. Part of the monitoring of coastal change involved the measurement...
-
Computationally-efficient design optimisation of antennas by accelerated gradient search with sensitivity and design change monitoring
PublicationElectromagnetic (EM) simulation tools are of primary importance in the design of contemporary antennas. The necessity of accurate performance evaluation of complex structures is a reason why the final tuning of antenna dimensions, aimed at improvement of electrical and field characteristics, needs to be based on EM analysis. Design automation is highly desirable and can be achieved by coupling EM solvers with numerical optimisation...
-
Coherent-wave Monte Carlo method for simulating light propagation in tissue
PublicationSimulating propagation and scattering of coherent light in turbid media, such as biological tissues, is a complex problem. Numerical methods for solving Helmholtz or wave equation (e.g. finite-difference or finite-element methods) require large amount of computer memory and long computation time. This makes them impractical for simulating laser beam propagation into deep layers of tissue. Other group of methods, based on radiative...
-
Comparison of Classification Methods for EEG Signals of Real and Imaginary Motion
PublicationThe classification of EEG signals provides an important element of brain-computer interface (BCI) applications, underlying an efficient interaction between a human and a computer application. The BCI applications can be especially useful for people with disabilities. Numerous experiments aim at recognition of motion intent of left or right hand being useful for locked-in-state or paralyzed subjects in controlling computer applications....
-
High-Resolution Discharge Forecasting for Snowmelt and Rainfall Mixed Events
PublicationDischarge events induced by mixture of snowmelt and rainfall are strongly nonlinear due to consequences of rain-on-snow phenomena and snowmelt dependence on energy balance. However, they received relatively little attention, especially in high-resolution discharge forecasting. In this study, we use Random Forests models for 24 h discharge forecasting in 1 h resolution in a 105.9 km 2 urbanized catchment in NE Poland: Biala River....
-
Applications of semi-definite optimization in quantum information protocols
PublicationThis work is concerned with the issue of applications of the semi-definite programming (SDP) in the field of quantum information sci- ence. Our results of the analysis of certain quantum information protocols using this optimization technique are presented, and an implementation of a relevant numerical tool is introduced. The key method used is NPA discovered by Navascues et al. [Phys. Rev. Lett. 98, 010401 (2007)]. In chapter...
-
ON EGNOS MONITORING IN LOCAL CONDITIONS
PublicationAny SBAS system should deliver to the user corrections to pseudoranges as well as information about the system integrity. In theory, as soon as the system is permanently monitored by RIMS stations, it is impossible to deliver the fault information to the user. However many observations shows that accuracy of EGNOS service in the same time are different in different places, which shows the influence of local conditions on them....
-
Properties of dimension witnesses and their semidefinite programming relaxations
PublicationIn this paper we develop a method for investigating semi-device-independent randomness expansion protocols that was introduced in Li et al. [H.-W. Li, P. Mironowicz, M. Pawłowski, Z.-Q. Yin, Y.-C. Wu, S. Wang, W. Chen, H.-G. Hu, G.-C. Guo, and Z.-F. Han, Phys. Rev. A 87, 020302(R) (2013)]. This method allows us to lower bound, with semi-definite programming, the randomness obtained from random number generators based on dimension...
-
Experimental and numerical investigations of ultimate strength of degradated structures
PublicationThe presented work investigates the corrosion influence on the structural behaviour of structural elements. Nine welded large-scale stiffened plates, and 30 standard small specimens have been subjected to the accelerated marine immersed conditions. After corrosion testing, the specimens have been accurately measured in terms of surface characteristics. The coupon specimens were furtherly subjected to tensile loading to develop...
-
Offshore benthic habitat mapping based on object-based image analysis and geomorphometric approach. A case study from the Slupsk Bank, Southern Baltic Sea
PublicationBenthic habitat mapping is a rapidly growing field of underwater remote sensing studies. This study provides the first insight for high-resolution hydroacoustic surveys in the Slupsk Bank Natura 2000 site, one of the most valuable sites in the Polish Exclusive Zone of the Southern Baltic. This study developed a quick and transparent, automatic classification workflow based on multibeam echosounder and side-scan sonar surveys to...
-
Assessment of Fuel Cells’ State of Health by Low-Frequency Noise Measurements
PublicationWe proposed applying low-frequency (flicker) noise in proton-exchange membrane fuel cells under selected loads to assess their state of health. The measurement set-up comprised a precise data acquisition board and was able to record the DC voltage and its random component at the output. The set-up estimated the voltage noise power spectral density at frequencies up to a few hundred mHz. We observed the evolution of the electrical...
-
SFEM Analysis of Beams with Scaled Lengths including Spatially Varying and Cross-Correlated Concrete Properties
PublicationThis paper presents the results obtained for plain concrete beams under four-point bending with spatially varying material properties. Beams of increasing length but constant depth were analyzed using the stochastic finite element method. Spatial fluctuation of a uniaxial tensile strength, fracture energy and elastic modulus was defined within cross-correlated random fields. The symmetrical Gauss probability distribution function...
-
Snapshot of micro-animals and associated biotic and abiotic environmental variables on the edge of the south-west Greenland ice sheet
PublicationMicroinvertebrates play a role as top consumers on glaciers. In this study we tested what kind of cryoconite material the animals inhabit (mud vs granules) on the edge of the Greenland ice sheet (GrIS) in the south-west. We also tested the links between the densities of micro-fauna in cryoconite material and selected biotic (algae, cyanobacteria, bacterial abundances) and abiotic (water depth, pH, ion content, radionuclides) factors....
-
Effect of User Mobility upon Trust Building among Autonomous Content Routers in an Information-Centric Network
PublicationThe capability of proactive in-network caching and sharing of content is one of the most important features of an informationcentric network (ICN). We describe an ICN model featuring autonomous agents controlling the content routers. Such agents are unlikely to share cached content with other agents without an incentive to do so. To stimulate cooperation between agents, we adopt a reputation and trust building scheme that is able...
-
Estimation of Coherence Bandwidth for Underwater Acoustic Communication Channel
PublicationA shallow underwater acoustic communication channel is characterized by strong multipath propagation. The signal reaching the receiver consists of a direct waveform and a number of its delayed and suppressed replica. A significant time dispersion of the transmitted signal and selective fading of its spectrum are observed. Coherence bandwidth defines maximal bandwidth, wherein the channel amplitude characteristic remains constant...
-
A multiparameter simulation-driven analysis of ship response when turning concerning a required number of irregular wave realizations
PublicationThe growing implementation of Decision Support Systems on modern ships, digital-twin technology, and the introduction of autonomous vessels cause the marine industry to seek accurate modeling of vessel response. Despite the contemporary 6DOF models can be used to predict ship motions in irregular waves, the impact of their stochastic realization is usually neglected and remains under-investigated. Especially in the case of turning, differences...
-
Światła miasta
PublicationKsiążka w całości poświęcona jest współczesnym trendom oświetlenia miast. Autorka przedstawia w niej: -zarys historyczny stosowania ośweitlenia w przestrzeniach publicznych, - funkcje użytkowe i dekoracyjne oświetlenia, - róznego rodzaju formy marketingu prowadzonego z wykorzystaniem światła. Ponadto publikacja przybliża nową rolę światła w mieście - interpretację przestrzeni świtłaem, ukazującą niecodzienne scenografie świetlne...
-
Finite element simulation of cross shaped window panel supports
PublicationThe aim of the work is to verify suitability of cross-shaped window panel supports for mullion-transom wall systems. The Finite Element Method (FEM) is chosen to determine the behaviour of stainless steel elements under loading. The advanced non-linear numerical simulations are carried out using an implicit FEM software package MSC.Marc. This study is proposed to initiate the comprehensive investigation of mechanical properties...
-
Plants sources of vitamins against SARS-CoV-2
Publication -
Wpływ smarowności na działania układu tribologicznego (impact of lubricity on the tribological system action)
Publicationthe paper presents analysis and evaluation, based on tests results, of the impact of lubricity of the used lubricating oils (shell argina t 40) on the action of boundary layer of sulzer 6zl40/48 engines aboard the ''włocławek'' sea-going ship. for comparison purposes, the same oils were tested with the ceramizer four-stroke engine (all types of the vidar four-stroke engines) regeneration agent added. so understood boundary layer...
-
Application of autoencoder to traffic noise analysis
PublicationThe aim of an autoencoder neural network is to transform the input data into a lower-dimensional code and then to reconstruct the output from this code representation. Applications of autoencoders to classifying sound events in the road traffic have not been found in the literature. The presented research aims to determine whether such an unsupervised learning method may be used for deploying classification algorithms applied to...