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Search results for: FINITE-DIFFERENCE TIME-DOMAIN METHODS
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Mitigating the Energy Consumption and the Carbon Emission in the Building Structures by Optimization of the Construction Processes
PublicationFor decades, among other industries, the construction sector has accounted for high energy consumption and emissions. As the energy crisis and climate change have become a growing concern, mitigating energy usage is a significant issue. The operational and end of life phases are all included in the building life cycle stages. Although the operation stage accounts for more energy consumption with higher carbon emissions, the...
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Microscopic Imaging to Visualize the Distribution of Dietary Nucleic Acids in Food Products of Various Origins
PublicationDietary nucleic acids (dietNAs) are being increasingly recognized as important food components with nutritional value. However, the precise dietary recommendations for dietNAs are limited, because established methods for determining the quantity and nutritional role of dietNAs are still lacking. One of the tools to narrow this gap could be microscopic imaging, as a convenient approach to visualize the abundance and distribution...
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Geographical Information Systems GIS (project) [2022/23]
e-Learning CoursesSubject: Geographical Information Systems GIS, Inter-faculty (field of study: Energy Technologies), undergraduate studies, full-time studies (semester 6) Teacher: dr inż. Andrzej Augusiak, doc. PG Abstract: The course aims to teach the practical implementation of a simple project in the field of GIS geographical information systems. As part of the project, the course participant will learn how to use the basic methods and tools...
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Hybrid Finite Element Method Development for Offshore Structures’ Calculation with the Implementation of Industry Standards
PublicationIn the design process of offshore steel structures, it is typical to employ commercial calculation codes in which simulationand evaluation of results are performed on the basis of the available standards (e.g. API, DNV, Lloyds). The modelingand solution rely on finite element methods and cover the simulation of the structure’s properties along with the influenceof the marine environment – sea currents, wave...
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Propagation Characteristics of Partial Discharges in an Oil-Filled Power Transformer
PublicationPower transformers are among the most important assets in the power transmission and distribution grid. However, they suffer from degradation and possible faults causing major electrical and financial losses. Partial discharges (PDs) are used to identify the insulation health status and their degradation level. PDs are incipient, low-magnitude faults caused by localized dielectric breakdown. Those activities emit signals in many...
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Numerical analyses of novel prefabricated structural wall panels in residential buildings based on laboratory tests in scale 1:1
PublicationThe paper presents experimental and numerical investigations on novel prefabricated composite building wall panels for residential building constructions. The wall panels were composed of reinforced concrete ribbed elements with the core from the EPS foam as the thermal insulation. The wall panels in the full-scale 1:1 were subjected to vertical loads. In the first step, the experiments were analysed with simple usual static methods....
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Linking optical and electronic properties to photoresponse of heterojunctions based on titania nanotubes and chromium, molybdenum, and tungsten oxides
PublicationThe development of photosensitization strategies for titanium dioxide is necessary for the enhancement of its optical and electronic properties towards its application potential in solar photoelectrochemistry. In this work, significant differences in the photosensitizing capability of the 6th group transition metal oxides applied on the surface of titania nanotubes are reported. For the first time, correlations between the experimentally...
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Modeling of Electrified Transportation Systems Featuring Multiple Vehicles and Complex Power Supply Layout
PublicationThe paper proposes a novel approach to modeling electrified transportation systems. The proposed solution reflects the mechanical dynamics of vehicles as well as the distribution and losses of electric supply. Moreover, energy conversion losses between the mechanical and electrical subsystems and their bilateral influences are included. Such a complete model makes it possible to replicate, e.g., the impact of voltage drops on vehicle...
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Dynamic Modeling of COVID-19 Disease with Impact of Lockdown in Pakistan and Malaysia
PublicationBeing researchers, it is an utmost responsibility to provide insight on social issues thus, this work addresses the dynamic modeling of first and most contagious disease named as COVID-19 caused by coronavirus. The first case of COVID-19 appeared in Pakistan was on 26th February 2020 and in Malaysia on 27th February 2020; both patients had foreign travel history. In the paper, the number of total affected cases and total deaths...
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Experimental and numerical investigation on shell and coil storage unit with biodegradable PCM for modular thermal battery applications
PublicationThermal energy storage (TES) in automotive applications is currently growing in importance. TES can visibly reduce primary energy consumptions, decrease CO2 emission, and improve thermal comfort in electric as well as hybrid vehicles. However, to meet the new ambitious target (15% reduction of CO2 emissions in the new cars until 2025) it is required to use plug-in electric vehicles. For this reason, this paper focuses on the optimization...
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Topological-numerical analysis of a two-dimensional discrete neuron model
PublicationWe conduct computer-assisted analysis of a two-dimensional model of a neuron introduced by Chialvo in 1995 [Chaos, Solitons Fractals 5, 461–479]. We apply the method of rigorous analysis of global dynamics based on a set-oriented topological approach, introduced by Arai et al. in 2009 [SIAM J. Appl. Dyn. Syst. 8, 757–789] and improved and expanded afterward. Additionally, we introduce a new algorithm to analyze the return times...
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Computed aided system for separation and classification of the abnormal erythrocytes in human blood
PublicationThe human peripheral blood consists of cells (red cells, white cells, and platelets) suspended in plasma. In the following research the team assessed an influence of nanodiamond particles on blood elements over various periods of time. The material used in the study consisted of samples taken from ten healthy humans of various age, different blood types and both sexes. The markings were leaded by adding to the blood unmodified...
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Detection of Anomalies in the Operation of a Road Lighting System Based on Data from Smart Electricity Meters
PublicationSmart meters in road lighting systems create new opportunities for automatic diagnostics of undesirable phenomena such as lamp failures, schedule deviations, or energy theft from the power grid. Such a solution fits into the smart cities concept, where an adaptive lighting system creates new challenges with respect to the monitoring function. This article presents research results indicating the practical feasibility of real‐time...
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Specific detection of Alternaria alternata by PCR and real-time PCR
PublicationFungi of Alternaria genus are cosmopolitan organisms, which spores can be found in the air, soil, water, clothing and food. They commonly occur as saprotrophs on the plant remains, contributing to the decomposition of organic matter. Additionally, they are components of the normal human and animal skin flora. Alternaria spp. are also known human allergens, causing hay fever and allergic reactions that can lead to the development...
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Experimental observations on the creep behaviour of frozen soil
PublicationConstitutive models in the literature for creep of frozen soil are based on the direct use of time counted from the onset of creep. An explicit time dependence in a constitutive equation violates the principles of rational mechanics. No change in stress or temperature is allowed for during creep, using the time-based formulations. Moreover, the existing descriptions need much verification and improvement on the experimental side...
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Komputerowo wspomagana analiza elastycznych siłowników elektrostatycznych dla potrzeb implementacji w systemach mechatroniki
PublicationPrzeprowadzone badania naukowe rozpoczęto od szczegółowej analizy układu mechatronicznego dłoni robotycznych, powstałych na przestrzeni ostatnich 40 lat, w celu dokładnego rozpoznania ich głównych wymogów konstrukcyjnych i ograniczeń systemowych. Z uwagi na brak dostępnych narzędzi do symulacji omawianych siłowników, w rozprawie opracowano uniwersalne narzędzie – program do analizy numerycznej. U jego podstawy założono wykorzystanie...
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Międzysektorowa mobilność zatrudnienia oraz płac a efektywność rynku pracy.
PublicationCelem artykułu jest uzyskanie odpowiedzi na pytanie, czy ocenę efektywności funkcjonowania rynków pracy, rozumianej jako zdolność rynków do „oczyszczania się”, można przedstawić za pomocą analizy międzysektorowej mobilności płac oraz zatrudnienia. W połowie lat 90. XX wieku Paul Krugman dowodził, iż negatywne szoki gospodarcze skutkują w krajach europejskich wzrostem bezrobocia, natomiast w USA wzrostem rozpiętości płac. Tymczasem...
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On a 3D material modelling of smart nanocomposite structures
PublicationSmart composites (SCs) are utilized in electro-mechanical systems such as actuators and energy harvesters. Typically, thin-walled components such as beams, plates, and shells are employed as structural elements to achieve the mechanical behavior desired in these composites. SCs exhibit various advanced properties, ranging from lower order phenomena like piezoelectricity and piezomagneticity, to higher order effects including flexoelectricity...
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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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Perfect thermal contact of hyperbolic conduction semispaces with an interfacial heat source
PublicationThe problem of thermal contact between two bodies with a heat source at their interface presents great scientific and practical interest. On the time scale of a nanosecond or shorter, heat propagation should be considered in the form of thermal waves of finite speeds. This study investigated the thermal behaviour of hyperbolic conduction semispaces in perfect thermal contact subjected to the action of an interfacial heat source....
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Tuning a Hybrid GPU-CPU V-Cycle Multilevel Preconditioner for Solving Large Real and Complex Systems of FEM Equations
PublicationThis letter presents techniques for tuning an accelerated preconditioned conjugate gradient solver with a multilevel preconditioner. The solver is optimized for a fast solution of sparse systems of equations arising in computational electromagnetics in a finite element method using higher-order elements. The goal of the tuning is to increase the throughput while at the same time reducing the memory requirements in order to allow...
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Dynamic F-free Coloring of Graphs
PublicationA problem of graph F-free coloring consists in partitioning the vertex set of a graph such that none of the resulting sets induces a graph containing a fixed graph F as an induced subgraph. In this paper we consider dynamic F-free coloring in which, similarly as in online coloring, the graph to be colored is not known in advance; it is gradually revealed to the coloring algorithm that has to color each vertex upon request as well...
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Accurate Modeling of Antenna Structures by Means of Domain Confinement and Pyramidal Deep Neural Networks
PublicationThe importance of surrogate modeling techniques has been gradually increasing in the design of antenna structures over the recent years. Perhaps the most important reason is a high cost of full-wave electromagnetic (EM) analysis of antenna systems. Although imperative in ensuring evaluation reliability, it entails considerable computational expenses. These are especially pronounced when carrying out EM-driven design tasks such...
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A Compact Basis for Reliable Fast Frequency Sweep via the Reduced-Basis Method
PublicationA reliable reduced-order model (ROM) for fast frequency sweep in time-harmonic Maxwell’s equations by means of the reduced-basis method is detailed. Taking frequency as a parameter, the electromagnetic field in microwave circuits does not arbitrarily vary as frequency changes, but evolves on a very low-dimensional manifold. Approximating this low-dimensional manifold by a low dimension subspace, namely, reduced-basis space, gives...
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2022-2023 - Wytrzymałość materiałów I, PG_00039799
e-Learning CoursesCelem przedmiotu jest zapoznanie studentów z podstawowymi zagadnieniami związanymi z wytrzymałością materiałów. Wykłady dotyczą kolejno: podstawy wytrzymałości materiałów, wytrzymałość pręta prostego na ściskanie/rozciąganie, analiza wytrzymałości dla układów prętowych statycznie niewyznaczalnych, wytrzymałość prętów na skręcanie, wytrzymałość belek zginanie, odkształcenia belki zginanej, ścinanie pręta (pręt ścinany), stany naprężeń,...
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State-of-the-art framework for high-speed camera and photogrammetric use in geometry evaluation of prestressed concrete failure process
PublicationPrestressed structures are a key to the realization of the boldest architectural ideas, regardless of shape complexity, great height and large span. A characteristic feature of the prestressed structure is the better use of concrete material properties by insertion of internal forces. The internal forces are opposed to external loads effects (forces and deformations of structure). Prestressed reinforced concrete beams are characterized...
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Next generation automatic IP configuration deployment issues
PublicationAlthough Dynamic Host Configuration Protocol for IPv6 (DHCPv6) protocol was defined in 2003, it was designed as a framework rather than a complete solution to the automatic configuration in IPv6 networks. There are still some unsolved problems and new options yet to be defined. One example of such case is Fully Qualified Domain Name (FQDN) option, which final version has been published in late 2007. It describes DHCPv6 client...
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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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EVALUATION OF 3D MODEL OF REBAR FOR QUANTITATIVE PARAMETERS
PublicationThe construction industry practices and processes are evolving constantly, and with the emergence of Industry 4.0, the use of technologies is expanding. Construction progress monitoring is an essential project lifecycle process; project success and timely completion are linked with effective progress monitoring operations and adopted tools. In the domain of automated construction progress monitoring, 3D modeling techniques have...
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Selected Features of Dynamic Voting
PublicationIn multi-agent systems composed of autonomous agents with local knowledge, it is often desirable to aggregate their knowledge in order to make an educated decision. One of the methods of agreeing to a common decision is voting. A new history-based dynamic weight protocol allows for identification of the agents which contribute to the correct system decision. The main advantage of this approach, compared to static weighted system...
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Impedance monitoring of corrosion degradation of plasma electrolytic oxidation coatings (PEO) on magnesium alloy
PublicationImpedance technique based on continuous multisinusoidal current perturbation was used to explain degradation process of plasma electrolytic oxidation coatings (PEO) on magnesium alloy. An obtained impedance spectrum was fitted by electrical equivalent circuit to describe properties of conversion layer on magnesium alloy. Additionally, galvanostatic mode maintained during experiment, with DC current equal to zero, allowed to achieve...
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Test Design Patterns for Embedded Systems,
PublicationTest suites for embedded systems are typically created from scratch using dif- ferent, often inadequate methods. In consequence, industry branches dealing with software-intensive embedded systems have to cope with quality problems, even though test processes are particularly time-consuming and costly. Based on an evolving model-based testing methodology we introduce test design patterns for simplifying and accelerating...
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Kinetics and mechanism of the chemically modified starches during gelatinization.
PublicationNative starch was silicated by means of microwave-assisted reactions with varying doses of reagents. Resulting products were characterized by DSC and HMR-relaxation methods. It was observed that the hydratation of the silicated starches during gelatinization decreases when compared to that of the native potato starch. The amount of unfrozen water for ungelitinizated silicated starches are less than in control samples. At the same...
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Synthesis and application of oligomer with hydroxy groups based on peroxy derivative of ED-24 epoxy resin and POLYTHF-2000 oligoether
PublicationNew oligomer with peroxy, primary and secondary hydroxy groups has been synthesized on the basis of peroxy derivative of ED-24 epoxy resin (PO) and PolyTHF-2000 oligoether according to the developed procedure. The effect of the catalysts nature and amount, temperature and process time on the reaction rate has been studied. Benzyltriethylammonium chloride, potassium hydroxide,1,4-diazobicyclooctane and the mixture composed of benzyltriethylammonium...
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Experimental Comparison of Straight Lines and Polynomial Interpolation Modeling Methods in Ship Evolutionary Trajectory Planning Problem
PublicationPaper presents the application of evolutionary algorithms and polynomial interpolation in ship evolutionary trajectory planning method and its comparison to classic approach, where trajectory is modeled by straight lines. Evolutionary algorithms are group of methods that allows\ to find a collision free trajectory in real time, while polynomial interpolation allows to model smooth trajectory, which keeps continuity of velocity...
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Analysis of radiometric signal in sedimentating suspension flow in open channel
PublicationThe article discusses issues related to the estimation of the sedimentating solid particles average flow velocity in an open channel using radiometric methods. Due to the composition of the compound, which formed water and diatomite, received data have a very weak signal to noise ratio. In the process analysis the known determining of the solid phase transportation time delay the classical cross-correlation function is the most...
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Collision Risk-Informed Weather Routing for Sailboats
PublicationSelected COLREG rules, good seamanship and sheer common sense indicate that it is in a sailboat's interest to follow collision-free routes without relying on large power-driven ships to give way. Until now, however, no method has integrated a sailboat's weather routing with collision risk monitoring and collision avoidance. Therefore, a new deterministic approach to combine the above features within one method is introduced here....
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Landscape of Automated Log Analysis: A Systematic Literature Review and Mapping Study
PublicationLogging is a common practice in software engineering to provide insights into working systems. The main uses of log files have always been failure identification and root cause analysis. In recent years, novel applications of logging have emerged that benefit from automated analysis of log files, for example, real-time monitoring of system health, understanding users’ behavior, and extracting domain knowledge. Although nearly every...
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Freehand drawing versus digital design tools in architectural teaching
PublicationThe oldest drawings resembling modern architectural designs date from the 22nd Century BC. Throughout history, the first drawings have evolved into the basic tool of the architect’s work. The exchange of information between the architect and the contractor began to take place through a drawing system, allowing to describe three-dimensional space using flat representations. With time, architectural drawings also began to resemble...
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Artificial intelligence for software development — the present and the challenges for the future
PublicationSince the time when first CASE (Computer-Aided Software Engineering) methods and tools were developed, little has been done in the area of automated creation of code. CASE tools support a software engineer in creation the system structure, in defining interfaces and relationships between software modules and, after the code has been written, in performing testing tasks on different levels of detail. Writing code is still the task...
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Reduction of measurement data before Digital Terrain Model generation vs. DTM generalisation
PublicationModern data acquisition technologies provide large datasets that are not always necessary in its entirety to properly accomplish the goal of the study. In addition, such datasets are often cumbersome for rational processing, and their processing is time and labour consuming. Therefore, methods that enable to reduce the size of the measurement dataset, such as the generalization of the Digital Terrain Model (DTM) or the reduction...
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Direct determination of cadaverine in the volatile fraction of aerobically stored chicken breast samples
PublicationTo supplement the currently used methods for poultry meat shelf life assessment, it might be necessary to develop a technique for rapid headspace analysis of volatiles with no prior sample preparation step. Biogenic amines, in particular cadaverine, are considered meat spoilage indicators. Described in this article are the results of a preliminary investigation of the applicability of proton transfer reaction mass spectrometry...
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Cable-stayed cantilever structures as an expat of unique application in the construction of a building located in seismic area – an author’s project of multifunctional building in Lisbon, Portugal
PublicationThe article presents numerical simulations for the modelling of seismic impact on the structure of unique cantilever cablestayed structure with application of two methods. The Response Spectrum method, in which a spectrum of the structure's responses to an earthquake's impact is generated and the Accelerogram method, in which we generate dynamic load in the form of a diagram of the connection between acceleration and time for...
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Optimizing Construction Engineering Management Using Metaheuristic Methods and Bayesian Networks
PublicationThe construction of buildings invariably involves time and costs, and disruptions impact ongoing construction projects. Crisis situations in management strategies, structural confusion, and finan-cial miscalculations often arise due to misguided decision-making. This article proposes a method that combines the learning of Bayesian Networks and heuristic techniques to optimize deci-sion-making processes in construction scheduling....
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A new method of presosns identification based on comparative analysis of 3D face models
PublicationThe article presents the use of modern close range photogrammetry for possessing highly accurate 3D models of the human face (including the ears). Modern methods used to obtain precise data describing the construction of a human face, and even the whole human body, should allow to get finished measurement material in a very short time. Those features belong to the optical scanning technology. Comparative analysis of models of the...
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The Selection of Anchoring System for Floating Houses by Means of AHP Method
PublicationThis paper indicates and analyses the use of anchoring systems, such as mooring piles, booms, mooring cables, and deadweight anchors with additional elastic connectors, which are the most frequently applied by the producers of floating houses. The selection of the most advantageous anchoring system is complicated and requires the application of quantitative and qualitative data and methods. This publication presents the results...
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Adapt Your Teacher: Improving Knowledge Distillation for Exemplar-free Continual Learning
PublicationIn this work, we investigate exemplar-free class incremental learning (CIL) with knowledge distillation (KD) as a regularization strategy, aiming to prevent forgetting. KDbased methods are successfully used in CIL, but they often struggle to regularize the model without access to exemplars of the training data from previous tasks. Our analysis reveals that this issue originates from substantial representation shifts in the teacher...
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Parallel implementation of background subtraction algorithms for real-time video processing on a supercomputer platform
PublicationResults of evaluation of the background subtraction algorithms implemented on a supercomputer platform in a parallel manner are presented in the paper. The aim of the work is to chose an algorithm, a number of threads and a task scheduling method, that together provide satisfactory accuracy and efficiency of a real-time processing of high resolution camera images, maintaining the cost of resources usage at a reasonable level. Two...
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Investigation of praseodymium and samarium co-doped ceria as an anode catalyst for DIR-SOFC fueled by biogas
PublicationThe Pr and Sm co-doped ceria (with up to 20 mol.% of dopants) compounds were examined as catalytic layers on the surface of SOFC anode directly fed by biogas to increase a lifetime and the efficiency of commercially available DIR-SOFC without the usage of an external reformer. The XRD, SEM and EDX methods were used to investigate the structural properties and the composition of fabricated materials. Furthermore, the electrical...
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A Data Driven Model for Predicting RNA-Protein Interactions based on Gradient Boosting Machine
PublicationRNA protein interactions (RPI) play a pivotal role in the regulation of various biological processes. Experimental validation of RPI has been time-consuming, paving the way for computational prediction methods. The major limiting factor of these methods has been the accuracy and confidence of the predictions, and our in-house experiments show that they fail to accurately predict RPI involving short RNA sequences such as TERRA RNA....