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Novel fast analytical method for indirect determination of MCPD fatty acid esters in edible oils and fats based on simultaneous extraction and derivatization
PublicationA novel method for indirect determination of MCPD esters levels in lipid samples has been developed. The method is based on combination of extraction and derivatisation in the same sample preparation step. It is achieved by the application of diethyl ether as extraction solvent for isolation of released from esterified forms analytes from water phase and dilution solvent for solid PBA – derivatisation agent. It is a noteworthy...
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New nanoadsorbent based on magnetic iron oxide containing 1,4,7,10-tetraazacyclododecane in outer chain (Fe3O4@SiO2-cyclen) for adsorption and removal of selected heavy metal ions Cd2+, Pb2+, Cu2+
PublicationMagnetic Fe3O4@SiO2-cyclen nanoparticles were prepared and used as adsorbent for Cd2+, Pb2+ and Cu2+ from aqueous solution removal process controlled with differential pulse anodic stripping voltammetry (DPASV) and hanging mercury drop electrode (HDME). Nanomaterial was synthesised in three-step process co-precipitation of Fe3O4 core, coating with silane and N-(3-(triethoxysilyl)propyl)-1,4,7,10-tetraazacyclododecane-1-carboxamide...
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Novel molecules containing structural features of NSAIDs and 1,2,3-triazole ring: Design, synthesis and evaluation as potential cytotoxic agents
PublicationFor the first time the template containing structural features of more than one NSAIDs and the 1,2,3-triazole ring was explored for the identification of potential cytotoxic agents. These new and complex molecules were predicted to be effective inhibitors of PDE4B by molecular modelling studies in silico. The multi-step synthesis of these compounds were carried out starting from the well-known drug nimesulide and involved the use...
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Synthesis and characterization of biopolyols through biomass liquefaction of wood shavings and their application in the preparation of polyurethane wood composites
PublicationThe sustainability of production systems in wood processing, wood industry, and wooden waste disposal is an important issue for European industry and society. Proper development of products based on renewable wood resources gives an opportunity to provide materials with long-term environmental, social, and economic sustainability. This study aims to establish a new way of forestry and agricultural waste materials utilization by...
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The In-House Method of Manufacturing a Low-Cost Heat Pipe with Specified Thermophysical Properties and Geometry
PublicationVarious types of heat pipes are available to purchase off the shelf, from various manufacturers, but most of them have strictly defined geometry and technical parameters. However, when there is a need to use a heat pipe (HP) with an unusual size and shape or working conditions other than the standard ones, it becomes very costly to order them from manufacturers, especially in small quantities, and only a few producers are willing...
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System wykrywania i przeciwdziałania spoofingowi GPS
PublicationSpoofing w systemach nawigacji satelitarnej jest atakiem elektronicznym, który polega na nieuprawnionej emisji sygnałów stanowiących imitacje rzeczywistych sygnałów odbieranych z satelitów. Powoduje on wyznaczenie nieprawidłowych informacji o czasie, położeniu i prędkości odbiornika. Z uwagi na trudność jego wykrycia, spoofing stanowi poważniejsze zagrożenie niż proste zagłuszanie sygnałów zakłóceniem o dużej mocy (ang. jamming)....
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Mechatronic Design Towards Investigation of the Temporo-Mandibular Joint Behaviour
PublicationA significant problem of the temporo-mandibular joint (TMJ) research is lack of data concerning geometry and position of TMJ discs. It leads to necessity of developing a driving method of the process optimization, which is based on chosen techniques of mechatronic design. In particular, the latter concerns a technique of experimentally supported virtual prototyping. On this stage, the research is characterized by well-verified...
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Electron scattering cross sections for 1-pentene, H2C=CH-(CH2)2CH3, molecules
PublicationCross sections, both experimental and theoretical, are reported for electron scattering from 1-pentene (C5H10) molecules. Absolute grand-total cross sections (TCSs) were measured at electron impact energies ranging from 1 to 300 eV, using a linear electron-transmission technique. The dominant behaviour of the experimental TCS energy function is a distinct asymmetric enhancement with the maximum located around 6.5 eV. Discernible...
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A Computationally Efficient Model for Predicting Successful Memory Encoding Using Machine-Learning-based EEG Channel Selection
PublicationComputational cost is an important consideration for memory encoding prediction models that use data from dozens of implanted electrodes. We propose a method to reduce computational expense by selecting a subset of all the electrodes to build the prediction model. The electrodes were selected based on their likelihood of measuring brain activity useful for predicting memory encoding better than chance (in terms of AUC). A logistic...
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Discovering Rule-Based Learning Systems for the Purpose of Music Analysis
PublicationMusic analysis and processing aims at understanding information retrieved from music (Music Information Retrieval). For the purpose of music data mining, machine learning (ML) methods or statistical approach are employed. Their primary task is recognition of musical instrument sounds, music genre or emotion contained in music, identification of audio, assessment of audio content, etc. In terms of computational approach, music databases...
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Surface sliding in human abdominal wall numerical models: Comparison of single-surface and multi-surface composites
PublicationDetermining mechanical properties of abdominal soft tissues requires a coupled experimental-numerical study, but first an appropriate numerical model needs to be built. Precise modeling of human abdominal wall mechanics is difficult because of its complicated multi-layer composition and large variation between specimens. There are several approaches concerning simplification of numerical models, but it is unclear how far one could...
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A New Approach to the PWM Modulation for the Multiphase Matrix Converters Supplying Loads with Open-End Winding.
PublicationThis article presents three variants of the Pulse Width Modulation (PWM) for the Double Square Multiphase type Conventional Matrix Converters (DSM-CMC) supplying loads with the open-end winding. The first variant of PWM offers the ability to obtain zero value of the common-mode voltage at the load's terminals and applies only six switches within the modulation period. The second proposal archives for less Total Harmonic Distortion...
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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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Low energy elastic scattering of electrons from hexafluoropropene (C3F6)
PublicationWe present cross sections from a joint experimental and theoretical study on elastic electron scattering from hexafluoropropene (C3F6) in the gas phase. The experimental results, using low energy electron spectroscopy, were obtained at incident electron energies of 0.5, 1, 1.5, 2, 3, 4, 5, 6, 10, 12, 15 and 20 eV, for scattering angles ranging from 10°to 130°. The theoretical method used in the computation of the integral, momentum...
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Minimizing Distribution and Data Loading Overheads in Parallel Training of DNN Acoustic Models with Frequent Parameter Averaging
PublicationIn the paper we investigate the performance of parallel deep neural network training with parameter averaging for acoustic modeling in Kaldi, a popular automatic speech recognition toolkit. We describe experiments based on training a recurrent neural network with 4 layers of 800 LSTM hidden states on a 100-hour corpora of annotated Polish speech data. We propose a MPI-based modification of the training program which minimizes the...
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FPGA-Based Implementation of Real Time Optical Flow Algorithm and Its Applications for Digital Image Stabilization
PublicationAn efficient simplification procedure of the optical flow (OF) algorithm as well as its hardware implementation using the field programmable gate array (FPGA) technology is presented. The modified algorithm is based on block matching of subsets of successive frames, and exploits one-dimensional representation of subsets as well as the adaptive adjustments of their sizes. Also, an l1-norm-based correlation function requiring no...
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Parametrized Local Reduced-Order Models With Compressed Projection Basis for Fast Parameter-Dependent Finite-Element Analysis
PublicationThis paper proposes an automated parametric local model-order reduction scheme for the expedited design of microwave devices using the full-wave finite-element method (FEM). The approach proposed here results in parameterized reduced-order models (ROMs) that account for the geometry and material variation in the selected subregion of the structure. In each subregion, a parameter-dependent projection basis is generated by concatenating...
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Evaluation of Medical Staff Satisfaction for Workplace Architecture in Temporary COVID-19 Hospital: A Case Study in Gdańsk, Poland
PublicationThis article analyses the architecture that was used in the temporary AmberExpo hospital in Gdańsk, Poland which was installed during the COVID-19 pandemic. The construction of this type of facility is often based on experimental approaches, aimed at caring for patients suffering from an infectious disease in emergency conditions. In order to assess the level of employee satisfaction with the architectural and technical elements...
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Genetic and Epigenetic Aspects of Atopic Dermatitis
PublicationAtopic dermatitis is a heterogeneous disease, in which the pathogenesis is associated with mutations in genes encoding epidermal structural proteins, barrier enzymes, and their inhibitors; the role of genes regulating innate and adaptive immune responses and environmental factors inducing the disease is also noted. Recent studies point to the key role of epigenetic changes in the development of the disease. Epigenetic modifications...
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Revalorisation of the Szewalski’s concept of the law of varying the last-stage blade retraction in a gas-steam turbine
PublicationThe article presents the implementations of the free vortex law to the blade of the last stage of a gas-steam turbine. First, a thermodynamic analysis was carried out, determining the parameters at the inlet, then the number of stages of the high and low-pressure part of the turbine was constructed, together with the kinematics and velocity vectors for subsequent stages of the axial turbine. The last step of article was to take...
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Fuzzy regresion approach to road safety analysis at regional level
PublicationRoad safety modelling on regional level of NUTS 2 in the EU is the complex issue and authors of this article indicate this in previous publications. NUTS 2 are basic regions for the application of regional policies (0.8-3 m inhabitants). During multivariate models development they discovered that it is difficult to make regression model well described all regions, even if they are from one country. In the first step Poisson model...
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Elimination of impulsive disturbances from archive audio files – comparison of three noise pulse detection schemes
PublicationThe problem of elimination of impulsive disturbances (such as clicks, pops, ticks, crackles, and record scratches) from archive audio recordings is considered and solved using autoregressive modeling. Three classical noise pulse detection schemes are examined and compared: the approach based on open-loop multi-step-ahead signal prediction, the approach based on decision-feedback signal prediction, and the double threshold approach,...
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Distribution Transformer with Multi-Zone Voltage Regulation for Smart Grid System Application
PublicationThe article presents four concepts of the multi-zone voltage regulation (MZVR) system. It is a combination of a distribution transformer with an on-load tap-changer, for step voltage regulation, and a power electronic converter, dimensioned for a fraction of MZVR power, realizing continuous voltage regulation, supplemented by a special switch, the so-called bypass. This allows voltage regulation at high resolution, wide range and...
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Synthesis of 2-amino-2,6-dideoxy-D-glucitol-6-sulfonic acid as a potential antifungal agent.
PublicationGlucosamine-6P (GlcN-6P) synthase catalyzes the first committed step in the biosynthetic pathway leading to the formation of UDP-GlcNAc, a sugar nucleotide precursor providing D-glucosamine for the formation of chitin and manoproteins. 2-Amino-2,6-dideoxy-D-glucitol-6-sulfonic acid is an analog of 2-amino-2-deoxy-D-glucitol 6-phosphate (GlcN-ol-6-P), a known inhibitor of GlcN-6-P synthase, in which the phosphate group of the latter...
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Substrate characterization in a electrochemically derived Manganium-Cobaltium thin films
Open Research DataManganium-Cobaltium thin films were electrochemically deposited on a Ni foams subsrates in a one-step process at −1.1 V vs. Ag/AgCl in an aqueous solution of differently concentrated Mn(NO3)2·4H2O and Co(NO3)2·6H2O with the deposition time limited by charges of 60, 120, and 200 mC at 25 °C. The concentration ratios of Mn(NO3)2·4H2O to Co(NO3)2·6H2O...
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Sol-gel derived lithium titanate powders measured by XPS method
Open Research DataFor sol-gel synthesis lithium acetate dehydrate from Alfa Aesar GmbH &Co and titanium (IV) butoxide 97% from Aldrich were used as reagents. Copper (II) nitrate from Alfa Aesar was used as a source of Cu dopant. It was added in the proper weight to get an x index equal 0, 0.1 and 0.2. In the first step lithium acetate and copper nitrate were dissolved...
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Budowanie zespołu wirtualnego - zasady i wyzwania
PublicationArtykuł dotyczy tworzenia i współpracy w zespole wirtualnym, który jest zaangażowany w realizację konkretnego celu, najczęściej projektu, wymagającego współdziałania osób rozproszonych geograficznie i / lub organizacyjnie, komunikujących się głównie za pomocą technologii IT. Zaprezentowano charakterystykę wirtualnej współpracy z uwzględnieniem zalet i zagrożeń wynikających z ograniczenia komunikacji bezpośredniej. Na podstawie...
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Identyfikacja obszarów o najsłabszym poziomie oferty publicznego transportu zbiorowego na przykładzie województwa pomorskiego
PublicationProjektowanie sieci transportu zbiorowego wymaga od projektanta wiedzy dotyczącej obecnej oferty przewozowej oraz umiejętności wyznaczenia efektu ewentualnych zmian. Obecnie wyzwanie to stoi także przed autorami planów transportowych, którzy zobowiązani są do opracowania zmian w sieci transportu zbiorowego na kilka najbliższych lat. Szczególnie istotnym etapem analizy oferty przewozowej jest identyfikacja obszarów o najsłabszej...
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Proces wytwarzania e-kursu. Studium przypadku.
PublicationArtykuł definiuje proces wytwarzania e-kursu i e-lekcji oraz kolejne jego etapy, zaczynając od okre - ślania celu i odbiorcy, a kończąc na udostępnieniu treści. Na podstawie opisanego procesu przedstawiane jest stu - dium przypadku dla e-kursu prowadzonego na studiach zaocznych na Wydziale ETI Politechniki Gdańskiej na przedmiocie Strategie informatyzacji. Artykuł pokazuje też ewaluację studium przypadku, zarówno na poziomie oceny...
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Predicting bankruptcy with the use of macroeconomic variables
PublicationRegarding the current global financial crisis, the firms can expect the increased uncertainty of their existence. The relevant literature includes extensive studies on bankruptcy prediction. Studies show that the most popular method used for prediction of firms' failures are discriminant analyses (30,3% of all models), then logit and probit models (21,3%), which all three are parametric models. The nature, the structure of the...
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HILS for the Design of Three-Wheeled Mobile Platform Motion Surveillance System with a Use of Energy Performance Index
PublicationCurrent tendency in mechatronic design requires the use of comprehensive development of an environment, which gives the possibility to prototype, design, simulate and integrate with dedicated hardware. The paper discusses the Hardware-In-the-Loop Simulations (HILS) mechatronic technique, used during the design of the surveillance system based on energy performance index. The presented test configuration (physical controller – emulated...
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Modelling and simulation of GPU processing in the MERPSYS environment
PublicationIn this work, we evaluate an analytical GPU performance model based on Little's law, that expresses the kernel execution time in terms of latency bound, throughput bound, and achieved occupancy. We then combine it with the results of several research papers, introduce equations for data transfer time estimation, and finally incorporate it into the MERPSYS framework, which is a general-purpose simulator for parallel and distributed...
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IoT protocols, architectures, and applications
PublicationThe proliferation of embedded systems, wireless technologies, and Internet protocols have enabled the IoT to bridge the gap between the virtual and physical world enabling the monitoring and control of the environment by data processing systems. IoT refers to the inter-networking of everyday objects that are equipped with sensing, computation, and communication capabilities. These networks can collaboratively interact and perform...
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Fast impedance measurement method using Laplace transformation
PublicationArtykuł przedstawia metodę pomiaru impedancji wykorzystującą rzeczywisty uskok jednostkowy step jako sygnał pobudzenia i transformację Laplace jako narzędzie analizy sygnału odpowiedzi testowanego obiektu. Metoda jest dedykowana do badania różnych obiektów technicznych (np. powłok antykorozyjnych, czujników gazu, ceramik, tkanek biologicznych itp.) gdy czas pomiaru nie może być długi. Przedstawiona metoda jest znana ale niezbyt...
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Challenges in preparing honey samples for chromatographic determination of contaminants and trace residues
PublicationThe determination of contaminations and residues in honey is of growing concern over past few years, especially that these compounds can not only diminish beneficial properties of honey but more importantly, if present in significant amounts, can pose serious threat to human health. Since honey is characterized by complex composition of the matrix sample, it is often necessary to apply clean-up step, in order to eliminate interfering...
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Fractional neutron point kinetics equations for nuclear reactor dynamics – Numerical solution investigations
PublicationThis paper presents results concerning numerical solutions to a fractional neutron point kinetics model for a nuclear reactor. The paper discusses and expands on results presented in (Espinosa-Paredes et al., 2011). The fractional neutron point kinetics model with six groups of delayed neutron precursors was developed and a numerical solution using the Edwards’ method was proposed (Edwards et al., 2002). The mathematical model...
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Direct chromatographic methods in the context of green analytical chemistry
PublicationWe review analytical protocols based on gas and liquid chromatography (GC and LC), but involving no sample preparation.Green analytical chemistry seeks to minimize negative impacts of analytical chemistry. Direct analytical methods ideally fulfillthis requirement, as they preclude sample preparation - the most polluting step of the analytical procedure.We describe examples of GC methodologies for environmental and food analysis...
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Polyurethanes as a carrier of drugs for gentamicin
PublicationGentamicin is one of the most popular drug and is widely used due to its antibiotic properties. 3% of world production of polyurethanes (PU) is dedicated to biomedical applications, where they can serve are parts of orthopedic prosthesis or artificial organs, disposable medical devices, wound and burn dressing, contact lenses among others. In the study, to obtain drug carriers, a combination of these two materials were prepared...
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Ship Resistance Prediction with Artificial Neural Networks
PublicationThe paper is dedicated to a new method of ship’s resistance prediction using Artificial Neural Network (ANN). In the initial stage selected ships parameters are prepared to be used as a training and validation sets. Next step is to verify several network structures and to determine parameters with the highest influence on the result resistance. Finally, other parameters expected to impact the resistance are proposed. The research utilizes...
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Synchronizacja komutacji tranzystorów z położeniem kątowym wirnika silnika w napędzie IPMSM z blokowym sterowaniem falownikiem
PublicationPraca dotyczy napędu elektrycznego z silnikiem synchronicznym z magnesami trwałymi, pracującego w strefie osłabiania strumienia, wykorzystującego blokowe sterowanie falownikiem tranzystorowym (ang. six-step). Dla rozważanego napędu zaproponowano zsynchronizowanie chwil przełączeń tranzystorów z osiągnięciem przez wirnik silnika charakterystycznych położeń kątowych. Zaproponowane rozwiązanie przebadano symulacyjnie w programie Simulink...
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Formation of the hollow nanopillar arrays through the laser-induced transformation of TiO2 nanotubes
PublicationIn the following article, we present a simple, two-step method of creating spaced, hollow nanopillars, from the titania nanotube arrays via pulsed laser-treatment. Due to the high ordering of the structure, the prepared material exhibits photonic properties, which has been shown to increase the overall photoefficiency. The optical and morphological changes in the titania nanotubes after pulsed laser-treatment with 532, 355, and...
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Abdominal Aortic Aneurysm segmentation from contrast-enhanced computed tomography angiography using deep convolutional networks
PublicationOne of the most common imaging methods for diagnosing an abdominal aortic aneurysm, and an endoleak detection is computed tomography angiography. In this paper, we address the problem of aorta and thrombus semantic segmentation, what is a mandatory step to estimate aortic aneurysm diameter. Three end-to-end convolutional neural networks were trained and evaluated. Finally, we proposed an ensemble of deep neural networks with underlying...
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Hybrid Method Analysis of Unshielded Guiding Structures
PublicationA combination of mode matching, finite element methods and generalized impedance matrix is presented in a context of propagation problems for open guiding structures. The computational domain is divided into two regions: the first one is a circular cylinder containing whole guiding structure and the second one surrounds this artificial cylinder. The impedance matrix is calculated with the use of finite element method in the first...
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The study on application of biopolyols obtained by cellulose biomass liquefaction performed with crude glycerol for the synthesis of rigid polyurethane foams
PublicationIn this work rigid polyurethane foams (PUR) were obtained by replacement of 0–70 wt% of petrochemical polyol with bio-polyol obtained via cellulose liquefaction in presence of crude glycerol. The foams with different content of a bio-polyol were prepared by single step method for NCO/OH ratio equals 1.5. The prepared materials were analyzed in terms of their morphology, chemical structure, thermal stability and basic physical and...
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Redukcja czasu analizy MZP przez ograniczenie rozmiaru rozwiązania
PublicationAnaliza drzew niezdatności jest uznaną metodą analizy bezpieczeństwa systemów. Notacja ECSDM pozwala definiować zależności czasowe między zdarzeniami drzewa oraz przeanalizować je w celu określenia zależności pomiędzy zdarzeniami z Minimalnych Zbiorów Przyczyn (MZP). Dzięki wprowadzeniu klasyfikacji zdarzeń z MZP można wyodrębnić zależności czasowe istotne dla zapobiegania wywoływania hazardu przez konkretny MZP. Pozostałe zależności...
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Analiza sterowania ułamkowego PIλDμ mocą reaktora jądrowego
PublicationW artykule przedstawiono syntezę regulatora PIλDμ niecałkowitego rzędu dla potrzeb sterowania mocą reaktora jądrowego lekko wodnego określanego, jako typu PWR (Pressurized Water Reactor). W tym celu wykorzystano nieliniowy model matematyczny reaktora PWR o parametrach skupionych obejmujący procesy generacji i wymiany ciepła oraz termicznych efektów reaktywnościowych. Nastawy regulatora PIλDμ niecałkowitego rzędu dobrano w sposób...
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Termooksydacyjna i fotooksydacyjna degradacja pianek poliuretanowych
PublicationPrzeprowadzono ocenę efektywności działania wybranych środków przeciwstarzeniowych w sztywnych piankach poliuretanowych, otrzymywanych na drodze syntezy jednoetapowej. Ocenę tę oparto na pomia-rach zmian barwy oraz wytrzymałości mechanicznej zsyntezowanych materiałów. Na podstawie analizy uzyskanych wyników stwierdzono, iż dodatek 3% mieszaniny I rzędowego antyutleniacza fenolowego oraz benzotriazolowego absorbera UV znacząco zmniejsza...
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Algorytmy wykrywania krawędzi w obrazie
PublicationWykrywanie krawędzi jest pierwszym etapem w cyfrowym przetwarzaniu obrazów. Operacja ta polega na usunięciu informacji takich jak kolor czy też jasność, a pozostawieniu jedynie krawędzi. Efektem tej operacji jest znaczna redukcja ilości danych do dalszej analizy. Pozwala to na zastosowanie w następnych etapach bardziej złożonych algorytmów rozpoznawania obiektów na podstawie kształtu. W artykule zaprezentowano zastosowanie algorytmów...
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Wpływ automatycznej kalibracji wizyjnego systemu pozycjonowania na dokładność lokalizacji elementu roboczego
PublicationW artykule przedstawiono strukturę i działanie automatycznego wizyjnego systemu pozycjonowania (PVS), który został zainstalowany na maszynie waterjet (WJ). Ponadto przeprowadzono analizę wpływu kalibracji na działanie PVS. Podstawę systemu stanowią dwie kamery internetowe zamontowane na przemysłowej maszynie WJ. W połączeniu z algorytmem identyfikacji, system przeznaczony jest do pozycjonowania WJ z dużą dokładnością. W tym celu...
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Magnetic field mapping along a NV-rich nanodiamond-doped fiber
PublicationIntegration of NV−-rich diamond with optical fibers enables guiding quantum information on the spin state of the NV− color center. Diamond-functionalized optical fiber sensors have been demonstrated with impressive sub-nanotesla magnetic field sensitivities over localized magnetic field sources, but their potential for distributed sensing remains unexplored. The volumetric incorporation of diamonds into the optical fiber core allows...