2020 - Repozytorium publikacji - Politechnika Gdańska

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Simulation of Signal Propagation Along Fractional-Order Transmission Lines
- Tomasz Stefański
- Damian Trofimowicz
- Jacek Gulgowski
2020
In this paper, the simulation method of signal propagation along fractional-order (FO) transmission lines is presented. Initially, fractional calculus and the model of FO transmission line are introduced. Then, the algorithm allowing for simulation of the nonmonochromatic wave propagation along FO transmission lines is presented. It employs computations in the frequency domain, i.e., an analytical excitation is transformed to the frequency domain, multiplications with phase factors are executed, and finally the result is transformed back to the time domain. This algorithm involves elementary functions only and the fast Fourier transformation, hence, computations are numerically efficient and accurate. However, applicability of the method is limited by the sampling theorem. Numerical results are presented allowing for the evaluation of the method.
Simulation of Wave Propagation in Media Described by Fractional-Order Models
- Tomasz Stefanski
- Jacek Gulgowski
2020 Pełny tekst
In this paper, algorithms for simulation of the wave propagation in electromagnetic media described by fractional-order (FO) models (FOMs) are presented. Initially, fractional calculus and FO Maxwell's equations are introduced. The problem of the wave propagation is formulated for media described by FOMs. Then, algorithms for simulation of the non-monochromatic wave propagation are presented which employ computations in the time domain (TD) and the frequency domain (FD). In the TD algorithm, the electromagnetic field is computed as a convolution of an excitation with Green's function formulated based on an improper integral and the Mittag-Leffler function. On the other hand, the FD algorithm transforms an analytic excitation to FD, executes multiplications with phase factors, and finally transfers back result to TD. This algorithm involves elementary functions only, hence, computations are significantly faster and accurate with its use. However, applicability of the FD algorithm is limited by the sampling theorem. Numerical results and computation times obtained with the use of both algorithms are presented and discussed in detail.
Simulation-Driven Antenna Modeling by Means of Response Features and Confined Domains of Reduced Dimensionality
- Anna Pietrenko-Dąbrowska
- Sławomir Kozieł
2020 Pełny tekst IEEE Access
In recent years, the employment of full-wave electromagnetic (EM) simulation tools has become imperative in the antenna design mainly for reliability reasons. While the CPU cost of a single simulation is rarely an issue, the computational overhead associated with EM-driven tasks that require massive EM analyses may become a serious bottleneck. A widely used approach to lessen this cost is the employment of surrogate models, especially data-driven ones: versatile and easily accessible. Yet, one of the unresolved issues remains the curse of dimensionality. Standard modeling techniques are merely capable of rendering surrogates for low-dimensional cases within narrow parameter ranges. In pursuit to overcome these limitations, a novel technique has been recently proposed, where the overall modeling process is carried out within a confined domain, set up based on performance specifications and spectral analysis of an auxiliary set of reference designs. This work offers a further development of the aforementioned method. Instead of tackling the entire antenna responses, only the selected characteristic points (relevant to the figures of interest considered in the antenna design process) are handled. This allows for achieving excellent model accuracy at a low computational cost. The proposed approach can be an attractive modeling alternative for systems with well-structured characteristics.
Simulations of hydro-fracking in rock mass at meso-scale using fully coupled DEM/CFD approach
- Marek Krzaczek
- Michał Nitka
- Jan Kozicki
- Andrzej Tejchman-Konarzewski
2020 Pełny tekst Acta Geotechnica
The paper deals with two-dimensional (2D) numerical modelling of hydro-fracking (hydraulic fracturing) in rocks at the meso-scale. A numerical model was developed to characterize the properties of fluid-driven fractures in rocks by combining the discrete element method (DEM) with computational fluid dynamics (CFD). The mechanical behaviour of the rock matrix was simulated with DEM and the behaviour of the fracturing fluid flow in newly developed and pre- existing fractures with CFD. The changes in the void geometry in the rock matrix were taken into account. The initial 2D hydro-fracking simulation tests were carried out for a rock segment under biaxial compression with one injection slot in order to validate the numerical model. The qualitative effect of several parameters on the propagation of a hydraulic fracture was studied: initial porosity of the rock matrix, dynamic viscosity of the fracking fluid, rock strength and pre- existing fracture. The characteristic features of a fractured rock mass due to a high-pressure injection of fluid were realistically modelled by the proposed coupled approach.
Simultaneous optical and electrochemical label-free biosensing with ITO-coated lossy-mode resonance sensor
- Mateusz Śmietana
- Marcin Koba
- Petr Sezemsky
- Katarzyna Szot-Karpińska
- Dariusz Burnat
- Vitezslav Stranak
- Joanna Niedziółka-Jönsson
- Robert Bogdanowicz
2020 Pełny tekst BIOSENSORS & BIOELECTRONICS
In this work we discuss a new label-free biosensing device based on indium tin oxide (ITO) overlaid section of a multimode optical fiber fused silica core. The sensor has been used to optical measurements also simultaneously interrogated electrochemically (EC). Due to optimized thickness and optical properties of ITO film, a lossy-mode resonance (LMR) could be observed in the optical domain, where electrical properties of the film allowed for application of the sensor as a working electrode in an EC setup. It has been confirmed that the LMR response depends on optical properties of the external medium, as well as potential applied to the electrode during cyclic voltammetry. After the ITO surface functionalization with amine groups and covalently attached biotin, the device has been applied for label-free biosensing of avidin in both the domains simultaneously. On the example of biotin-avidin detection system it was demonstrated that when avidin concentration increases a decrease in current and increase in LMR wavelength shift were recorded in EC and optical domain, respectively. Both optical and EC responses follow the protein interaction process, and thus can be used as cross-verification of the readouts. Moreover, an extended information has been achieved comparing to solely EC interrogation, i.e., the grafting process of biotin and avidin was directly monitored optically displaying individual steps of an incubation procedure.
Simultaneous Removal of Hexane and Ethanol from Air in a Biotrickling Filter—Process Performance and Monitoring Using Electronic Nose
- Piotr Rybarczyk
- Bartosz Szulczyński
- Jacek Gębicki
2020 Pełny tekst Sustainability
Biofiltration is a well-accepted method for the removal of malodorous compounds from air streams. Interestingly, the mechanisms underlying this process are not fully understood. The aim of this paper was to investigate the simultaneous removal of hydrophobic hexane with hydrophilic ethanol, resulting in the enhanced removal of hexane in the presence of ethanol. Investigations were performed in a peat-perlite packed biotrickling filter and the process performance was monitored using both gas chromatography and electronic nose techniques. The results indicate that the length as well as the eciency of biofiltration during the start-up period depend on the feed composition, with higher eciency obtained when hexane and ethanol were fed together from the process initiation. The experiments in the steady-state period present the biofilter performance when dierent ratios of hydrophilic to hydrophobic compounds were fed to the biofilter. The obtained results show the synergistic eects of the addition of a hydrophilic compound on the removal eciency of hydrophobic hexane. The influence of the ratio of hydrophilic to hydrophobic compounds is discussed in terms of enhancing the mass transfer phenomena for hydrophobic volatile organic compounds.
Simultaneous voltammetric determination of Cd2+, Pb2+, and Cu2+ ions captured by Fe3O4@SiO2 core-shell nanostructures of various outer amino chain length
- Amanda Kulpa
- Jacek Ryl
- Grzegorz Schroeder
- Adrian Koterwa
- Jacek Sein Anand
- Tadeusz Ossowski
- Paweł Niedziałkowski
2020 Pełny tekst JOURNAL OF MOLECULAR LIQUIDS
In the present study, we examined a novel functionalised magnetic nanoparticles Fe3O4@SiO2-Nn as a nano adsorbent for binding of Cd2+, Pb2+, Cu2+ ions in an aqueous solution. First, we obtained the nanoparticles functionalised with various carbon chains containing different number of amino groups: (3-amino)propyltriethoxysilane (Fe3O4@SiO2-N1), N-(2-aminoethyl)-3-aminopropyltrimethoxysilane (Fe3O4@SiO2-N2) and N1-(3-trimethoxysilylpropyl)diethylenetriamine (Fe3O4@SiO2-N3). In the next step, we conducted their characterisation using SEM, TEM, FT-IR, and XPS methods. The detection of Cd2+, Pb2+, Cu2+ metal ions was performed under optimised experimental conditions using DPASV and HDME techniques. Using these methods we conducted the Cd2+, Pb2+, Cu2+ binding comparison in 4.5 μM concentration with 4 mg of Fe3O4@SiO2-Nn. Obtained results show that the adsorption rate of each ion differs due to the nanoparticles modification. The highest Pb2+ binding capacity was achieved using Fe3O4@SiO2-N1 and Fe3O4@SiO2-N2. The smallest binding capacity was observed for Cd2+ ions by Fe3O4@SiO2-N2 and Fe3O4@SiO2-N1. The Cd2+ biding was not observed for both Fe3O4@SiO2-N2 and Fe3O4@SiO2-N3 nanoparticles. Additionally, Pb2+ was not bound by Fe3O4@SiO2-N3. The research results show that the Fe3O4@SiO2-N3 nanoparticles bind copper ions with high selectivity. For the first time we performed the adsorption-desorption experiments using DPASV to prove the Cu2+ binding activity of Fe3O4@SiO2-N3 nanoparticles. Obtained results indicate that examined nanoparticles show strong binding capability. Additionally, we obtained 99.9% recovery of Cu2+ ions.
Single and Three -Phase PWM AC/AC Converters as Semiconductor Transformers
- Ryszard Strzelecki
- Natalia Strzelecka
2020 Pełny tekst
AC voltage transformation circuits contain pure or reactance PWM AC/AC converters. These circuits can be treated as AC/AC semiconductor transformers. This paper reviews single-phase and three-phase topologies: both non-isolated and isolated, single as well as two quadrant structure. Additionally, this paper present selected examples of their applications.
Single crystal growth and physical properties of MCo2Al9 (M= Sr, Ba)
- Zuzanna Ryżyńska
- Tomasz Klimczuk
- Michał Winiarski
2020 Pełny tekst JOURNAL OF SOLID STATE CHEMISTRY
Single crystals of SrCo2Al and BaCo2Al9 were grown using a self-flux method. A LeBail analysis of the powder X-ray diffraction patterns show that both compounds crystallize in a hexagonal (P6/mmm) crystal structure with lattice parameters: a = 7.8995(1) Å, c = 3.9159(1) Å for SrCo2Al9, and a = 7.9162(2) Å, c = 3.9702(1) Å for BaCo2Al9 aluminide. The low temperature analysis of the heat capacity measurements give a Sommerfeld coefficient γ = 4.99(6) mJ mol−1 K−2 for SrCo2Al9 and almost twice larger γ = 7.94(9) mJ mol−1 K−2 for BaCo2Al9. Resistivity measurements show metallic-like behavior, with reasonably large residual resistivity ratio RRR = 6 and 10 for SrCo2Al9 and BaCo2Al9, respectively. Neither heat capacity nor resistivity measurements reveal any phase transition down to 1.8 K.
Single-step grown boron doped nanocrystalline diamond-carbon nanograss hybrid as an efficient supercapacitor electrode
- Debosmita Banerjee
- Kamatchi J Sankaran
- Sujit Deshmukh
- Mateusz Ficek
- Chien-Jui Yeh
- Jacek Ryl
- I-Nan Lin
- Robert Bogdanowicz
- Aloke Kanjilal
- Ken Haenen
- Susanta Sinha Roy
2020 NANOSCALE
Direct synthesis of nano-structured carbon hybrid consisting of vertically aligned carbon nanograss on top of boron-doped nanocrystalline diamond is demonstrated and the carbon hybrid is further applied as an electrode material for the fabrication of supercapacitor. The hybrid film combines the dual advantages of sp2 (carbon nanograss) and sp3 (nanocrystalline diamond) bonded carbon, possessing not only the excellent electrical characteristics of sp2 carbon but also exceptional electrochemical stability of sp3 carbon. As a result, the specific capacitance of the as-prepared hybrid material reaches upto 0.4 F cm-2, one of the highest reported in diamond-based supercapacitors. The entire electrochemical results exhibit enhanced electron transfer efficiency with remarkable stability of 95% of capacitance retention even after 10000 cycles.
Skład chemiczny wód podziemnych dopływających z Pobrzeża Kaszubskiego do Zatoki Puckiej
- Dawid Potrykus
- Małgorzata Pruszkowska-Caceres
- Beata Jaworska-Szulc
- Anna Gumuła-Kawęcka
- Adam Szymkiewicz
2020 Pełny tekst Przegląd Geologiczny
Zatoka Pucka jest płytkim akwenem morskim szczególnie wrażliwym na dopływ biogenów z otaczających obszarów lądowych. Postępujący problem eutrofizacji wód zatoki wymaga podjęcia działań badawczych i naprawczych, w tym również odpowiedzi na pytanie czy i w jaki sposób spływające do zatoki wody podziemne wpływają na zjawisko eutrofizacji. Celem przeprowadzonych badań, przedstawionych w niniejszym artykule, było określenie składu chemicznego wód podziemnych wraz z analizą ich jakości na wysoczyznowym obszarze Pobrzeża Kaszubskiego. Analizując wyniki badań można uznać, iż skład chemiczny wydzielonych poziomów wodonośnych jest zbliżony. Wykazuje jednak zmienność parametrów hydrogeochemicznych w czasie, zmienność wraz ze wzrostem głębokości występowania wód podziemnych oraz mozaikowy rozkład przestrzenny. Zanieczyszczenie wód podziemnych dotyczy przede wszystkim wód poziomu zawieszonego Qz oraz górnego poziomu wodonośnego Q1, i występuje jedynie punktowo. Zatoka Pucka jest obszarem drenażu wód podziemnych poziomów Q1 i Q2. Stwierdzono, że w wodach podziemnych dopływających do zatoki stężenia większości analizowanych parametrów hydrogeochemicznych nie przekraczają norm jakościowych dla I i II klasy (wody bardzo dobrej i dobrej jakości).
Skośna kryza segmentowa do pomiaru przepływającego strumienia płynu
- Andrzej Mrowiec
- Marcin Heronimczak
- Anna Golijanek-Jędrzejczyk
2020
Przedstawiono prototypową skośną kryzę segmentową, którą cechuje to, że w zwężkowym układzie pomiaru strumienia objętości wykorzystano pochyloną płaszczyznę kryzy segmentowej. Płyn napierając na kryzę spływa po jej powierzchni. Przyjęto kąt napływu α między płaszczyzną kryzy segmentowej a kierunkiem przepływu (osią rurociągu) mniejszy od kąta prostego. Wyniki symulacji numerycznych oraz badań przepływowych przez zwężkowy przepływomierz ze skośną kryzą segmentową, przy jej pochyleniu α = 60° i przewężeniu β = 0,5, przedstawiono w postaci wykresów i map rozkładu ciśnienia statycznego.
Skuteczność nowoczesnych algorytmów optymalizacji czerpiących inspirację z procesów naturalnych
- Zuzanna Klawikowska
- Bartosz Puchalski
2020 Pełny tekst Zeszyty Naukowe Wydziału Elektrotechniki i Automatyki Politechniki Gdańskiej
Ze względu na nieistnienie uniwersalnego algorytmu optymalizacji rozwiązującego wszystkie problemy naukowo techniczne opracowywanie nowych i wydajniejszych obliczeniowo algorytmów optymalizacyjnych wciąż jest popularnym zadaniem. Przeglądając literaturę z dziedziny optymalizacji można zauważyć trend tworzenia „wymyślnych” algorytmów opartych na procesach naturalnych. W artykule sprawdzono skuteczność nowo powstałych algorytmów meta-heurystycznych zainspirowanych życiem owadów i zwierząt – czarnych wdów (algorytm BWO) oraz szarego wilka (algorytm GWO). Skuteczność działania wybranych algorytmów porównano z klasycznym algorytmem quasi Newtonowskim BFGS oraz strategią ewolucyjną CMA-ES, które charakteryzują się solidnym uwarunkowaniem matematycznym. W celach porównawczych wykorzystano 3 wybrane funkcje testowe. W ramach badań sprawdzono również wpływ liczby zmiennych decyzyjnych na czas uzyskiwania rozwiązania.
Slurry Surfacing Mixes on the Basis of Bitumen Modified with Phenol-Cresol-Formaldehyde Resin
- Yuriy Demchuk
- Volodymyr Gunka
- Serhiy Pyshyev
- Iurii Sidun
- Yurii Hrynchuk
- Justyna Kucińska-Lipka
- Michael Bratychak
2020 Pełny tekst Chemistry & Chemical Technology
Slow-breaking monophase cationic bitumen emulsions have been produced on the basis of bitumen modified with phenol-cresol-formaldehyde resin (PhCR-F). Bitumen emulsions were used as a binder for thin-layer coatings with slurry surfacing mixes (SSM). Physical and technical parameters of modified and unmodified emulsions were determined and analyzed. The optimal compositions of SSM were selected according to the breaking criterion. The values of SSM wet track abrasion were determined. It was found that the addition of PhCR-F allows to improve the adhesion properties of the thin-layer coatings.
Small Vessel with Inboard Engine Retrofitting Concepts; Real Boat Tests, Laboratory Hybrid Drive Tests and Theoretical Studies
- Wojciech Leśniewski
- Daniel Piątek
- Konrad Marszałkowski
- Wojciech Litwin
2020 Pełny tekst ENERGIES
The development of modern technologies and their increasing availability, as well as the falling costs of highly ecient propulsion systems and power sources, have resulted in electric or hybrid propulsions systems’ growing popularity for use on watercraft. Presented in the paper are design and lab tests of a prototype parallel hybrid propulsion system. It describes a concept of retrofitting a conventionally powered nine meter-long vessel with the system, and includes results of power and eciency measurements, as well as calculations of the vessel’s operating range under the propulsion of its electric motor. The concept of adding of a solar panels array was studied.
Smart acoustic band structures
- Wiktor Waszkowiak
- Arkadiusz Żak
- Magdalena Palacz
- Marek Krawczuk
2020
Smart acoustic band structures exhibit very interesting and non-standard physical properties due to the periodic nature of their certain characteristic on different scale levels. They manifest mostly in their frequency spectra as socalled frequency band-gaps or stop-bands, what has a great impact on the behaviour of these structures in relation to the propagation of vibro-acoustic signals that can be transmitted through the structures in some precisely defined frequency bands. Properties of acoustic band structures are directly linked to their geometry on the level of the unit cell, which parameters determine structural dynamics of such structures on the macroscopic scale. Here the piezoelectric transducers play a significant role. The combined exploitation of active properties of acoustic band structures equipped with active piezoelectric elements, in order to filter or damp transmitted vibro-acoustic signals, allows for very effective their applications. In their paper, the authors present certain results of certain computer simulations by the time-domain spectral finite element method, related to 1-D smart active and passive acoustic band structures supplemented with experimental measurements.
Smart Decisional DNA Technology to Enhance Industry 4.0 Environment in Conjunction with Conventional Manufacturing
- Imran Shafiq
- Cesar Sanin
- Edward Szczerbicki
2020
Knowledge-based support has become an indispensable part not only to the traditional manufacturing set-ups but also to the new fast-emerging Industry 4.0 scenario. In this regard, successful research has been performed and extensively reported to develop Decisional DNA based knowledge representation models of engineering object and engineering process called Virtual engineering object (VEO), Virtual engineering process (VEP) and Virtual engineering factory (VEF). These models are the virtual representation of manufacturing resources, and with the help of IoT, are capable of capturing the past experience and formal decisions. In this chapter, a complete virtual manufacturing environment is summarized. Furthermore, the scope of this work is explained in the Cyber-Physical Systems (CPS) based Industry 4.0 framework. Four case studies are presented to validate the practical implementation of the proposed concept. In the first case the idea of VEO-VEP-VEF is applied to design an intelligent factory framework to achieve contextual information through real-time visualization. In the second study, the smart tool performance analysis is presented in which data of key tool parameters like tool life, surface integrity, tool forces, and chip formation can be sensed in real-time; also predictions can be made according to the specific requirements. In the third case study, the technique of Decisional DNA (DDNA) is applied to FMS to develop a generic model to achieve effective scheduling and manufacturing flexibility. In the last study, the framework to manage the storage, analysis, and processing of data, information, and knowledge of a typical CIM is presented. The benefits of this approach are manifold as it creates manufacturing DNA of a factory, felicitates in effective decision making, increases the rate of production, reduces errors and production waste, and streamlines manufacturing sub-systems. Moreover, and can be instrumental in designing Industry 4.0.
Smart Embedded Systems with Decisional DNA Knowledge Representation
- Zhang Haoxi
- Fei Li
- Cesar Sanin
- Edward Szczerbicki
2020
Embedded systems have been in use since the 1970s. For most of their history embedded systems were seen simply as small computers designed to accomplish one or a few dedicated functions; and they were usually working under limited resources i.e. limited computing power, limited memories, and limited energy sources. As such, embedded systems have not drawn much attention from researchers, especially from those in the artificial intelligence area. Thanks to the efforts of scientists over recent years, great progress has been made in both computer hardware and software, which enables us to have much more powerful computers in very small sizes and with many more functions. Consequently, new expectations and needs for embedded systems have increased considerably. Today, smart embedded systems are expected, which are supposed to have capability to learn from past task executions and evolve their performance based on learnt knowledge, and assist users to make good decisions more efficiently. Therefore, how to make embedded systems smart is becoming one of the researchers’ new challenges. In this chapter, we introduce the Experience-Oriented Smart Embedded Systems (EOSES) that is proposed as a new technological scheme providing embedded systems with capabilities for experiential knowledge capturing, storage, reuse, evolving, and sharing. In this scheme, knowledge is represented as the Set of Experience Knowledge Structure (SOEKS or shortly SOE) and organized as Decisional DNA. The scheme is mainly based on conceptual principles from embedded systems and knowledge management. The objective behind this research is to offer large-scale support for intelligent, autonomous, and coordinated knowledge management on various embedded systems. Several conceptual elements of this research have been implemented in testing prototypes, and the experimental results show that the EOSES scheme can not only provide active knowledge management to different embedded systems, it can also enable various systems to learn from their daily operations in many different fields to acquire valuable knowledge, assist decision making, reduce human workers’ workload, and improve the system’s performance. As a result, the EOSES has great potential for meeting today’s demands for embedded systems, and providing a universe knowledge management scheme for mass autonomous mechanisms.
Smart Innovation Engineering Using Set of Experience and Decisional DNA
- Mohammad Waris
- Cesar Sanin
- Edward Szczerbicki
2020
Knowledge-based Engineering Systems are founded upon integration of knowledge into computer systems and are one of the core requirements for the future Industry 4.0. Since the fourth industrial revolution is passing through the developing phase, implementation of Cyber-Physical Production Systems require more realistic approach. Knowledge Management and Knowledge Engineering plays an important role in manufacturing industries facing global competition. One of the most promising areas where Knowledge Management is studied and applied is product innovation. This chapter presents the idea of Smart Innovation Engineering (SIE) System based on Set of Experience and Decisional DNA that facilitates the process of product innovation. It collects the experiential knowledge from the formal decisional event from the group of similar products having some common functions and features. The SIE system behaves like a group of experts in its domain as it collects, captures and stores the experiential knowledge and reuses this experiential knowledge as well that ultimately enhances the innovation process. The analysis of basic concepts and implementation method proves that SIE system is an advanced form of Cyber Physical Systems. It is flexible, systematic, fast, and supports customization. It can play a vital role towards Industry 4.0 development.
Smart Services for Improving eCommerce
- Andrzej Sobecki
- Julian Szymański
- Henryk Krawczyk
- Higinio Mora-Mora
- David Gil
2020
The level of customer support provided by the existing eCom-merce solutions assumes that the person using the functionality of theshop has sufficient knowledge to decide on the purchase transaction. Alow conversion rate indicates that customers are more likely to seekknowledge about the particular product than finalize the transaction.This is facilitated by the continuous development of customers’ digi-tal competencies, resulting in the increasing popularity of web servicesenabling the exchange of information, e.g. through social networks. Cur-rently the user act with eCommerce platform like a source of informa-tion. At the same time, he or she usually use more than one source ofinformation e.g., web portals, social networks, etc. The existing onlineshops seem unsuited to these trends because they remain simple tradingplatforms without integration with external web services and sources ofknowledge. New categories of smart services are suggested, enabling thenewly implemented eCommerce network platform to enhance the offeredknowledge and reduce the abandonment of the platform by the user. Ourempirical studies show an increase in the conversion rate in the case ofshops which increased the level of customer support using the proposedmodel of integration.