2019 - Repozytorium publikacji - Politechnika Gdańska

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Publikacje z roku 2019

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Quality increase for single-welded joints of thin-walled structures by means of simulation modelling
- Myroslav Panchuk
- Oleh Matviienkiv
- Lubomyr Shlapak
- Marek Szkodo
- Wojciech Kiełczyński
- Andrii Panchuk
2019 Pełny tekst REVISTA DE METALURGIA
The Simulation calculation module and the SolidWorks software package have helped to define the optimal shape and dimensions of single-welded joints which may serve the basis for calculating the process parameters of welding. Having compared the models with different weld cross-sections the authors have defined that the weld height and width do not significantly affect the stress concentration, and the stress concentration and value mainly depend on the shape of the root bead and the gap size between the welded parts
Quality Parameters in IMS/NGN Networks
- Sylwester Kaczmarek
- Maciej Sac
2019
The Next Generation Network (NGN) architecture, including elements of the IP Multimedia Subsystem (IMS) concept, is a proposition of a telecommunication network dedicated to the needs of current and future information society. The main goal of NGN is to provide Quality of Service (QoS), for which proper network design is necessary with respect to among others standardized call processing performance parameters, including expected values of Call Set-up Delay (E(CSD)) and Call Disengagement Delay (E(CDD)). These aspects are the subject of the paper, in which analytical and simulation traffic models of IMS/NGN are described, allowing assessment of E(CSD) and E(CDD). As the simulation model reflects the phenomena taking place in real IMS/NGN network, it is used as a reference for evaluation of quality of the analytical results, obtained using different queuing system models. Consequently, the queuing system models most appropriate for engineering applications are indicated. Moreover, application of the proposed analytical traffic model for design of IMS/NGN service stratum resources is presented and discussed.
Quantification of unconjugated and total ibuprofen and its metabolites in equine urine samples by gas chromatography–tandem mass spectrometry: Application to the excretion study
- Emilia Waraksa
- Mateusz Woźniak
- Laura Banaszkiewicz
- Ewa Kłodzińska
- Mariusz Ozimek
- Robert Wrzesień
- Barbara Bobrowska-Korczak
- Jacek Namieśnik
2019 MICROCHEMICAL JOURNAL
Ibuprofen (IBU) is a widely used nonsteroidal anti-inflammatory drug (NSAID) in human and also veterinary medicine. NSAIDs are usually highly metabolized compounds in horses; they are often present in equine urine, mostly in their conjugated forms (glucuronides). Thus, hydrolysis to cleave the glucuronide linkage prior to anti-doping analysis is often necessary for improving detection. In this study, unconjugated and total IBU and its metabolites were determined by GC–MS/MS in equine urine samples collected after drug administration to six horses (mares and geldings). The results indicated that enzymatic hydrolysis using β-glucuronidase from E. coli improved the detection of IBU and its phase I metabolites in equine urine samples; in a few cases, this method allowed to monitor analytes for a longer period of time. The percentages of conjugated analytes were within 5.4–48.4% for IBU and in the range of 0.2–55.5% for phase I metabolites of IBU. Unchanged IBU was found at the highest concentration levels in equine urine samples collected after drug administration; and also parent compound lasted for a longer period of time in equine urine than its phase I metabolites, with the exception of samples collected from one horse, in which 2-OH IBU was detectable for a longer duration than IBU.
Quantitative assessment
- Piotr Konieczka
- Małgorzata Rutkowska
2019
The main trends in the development of analytical chemistry are the determination of increasingly lower concentrations of analytes in samples with complex matrix composition (trace analysis). While the obtained analytical results must be reliable, which means that they must accurately (truly and precisely) reflect the actual content of analytes in a representative sample of the material object under study. However, it is an extremely difficult and complicated task, which is a great challenge for analysts. Therefore, it is becoming increasingly important to pay attention to the problem of quality assurance and quality control (QA/QC)of the obtained results. This chapter provides information on QA/QC systems. The terms for quality of the results - its relevance and consequences, uncertainty estimation, traceability, measurement errors (types and effects) are also described.
Quasi-analytical Near-to-Far Field Transformation Based on Field Matching Method for Scattering Problems
- Małgorzata Warecka
- Piotr Kowalczyk
- Rafał Lech
2019 Pełny tekst
A new quasi-analytical near-to-far ﬁeld transformation based on ﬁeld matching method (ﬁeld expansion in a base of Hankel functions) is presented. This approach uses ﬁnite element method to obtain near ﬁeld, then the ﬁeld is expressed in a base of Hankel functions. The evaluated coefﬁcients allow to calculate the ﬁeld outside the numerical domain, also in a far distance. The main advantage of the proposed technique is avoiding of the Green’s function integration. The method can be applied for obstacles of an arbitrary cross section and homogeneous in one direction. In order to conﬁrm the validity of the presented techniquethreedifferentstructureswereanalyzedandtheresults were veriﬁed with the other methods.
Quasi-discrete modelling of PMSM phase currents in drives with low switching-to-fundamental frequency ratio
- Leszek Jarzębowicz
2019 Pełny tekst IET Power Electronics
This study proposes a new quasi-discrete approach to modelling the permanent magnet synchronous motor (PMSM). The quasi-discrete modelling reflects the impact of continuous rotor movement, which takes place during a control cycle, on the shape of motor current waveforms. This provides much improvement in current modelling accuracy under inverter low switching-to-fundamental frequency operation. The proposed approach may be used in predictive control to compute current at forthcoming instants or in classical control to improve precision of determining mean current feedback. The superior accuracy of the quasi-discrete model is confirmed by simulation and experiment for an exemplary PMSM drive operating at inverter switching frequency of 5 kHz and fundamental frequency reaching 400 Hz.
Racjonalne wymiarowanie osadników wirowych
- Marlena Gronowska-Szneler
- Jerzy Sawicki
2019 Gaz, Woda i Technika Sanitarna
Wobec braku w literaturze metody wymiarowania osadników wirowych, zaproponowano kryteria projektowe, bazujące na analizie wpływu siły odśrodkowej ma ruch cząstki zawiesiny oraz na czas jej przebywania w osadniku. Kryteria zostały pozytywnie zweryfikowane empirycznie. Maja prostą postać matematyczną, więc mogą być bez trudu stosowane w praktyce.
Radar data fusion in the STRADAR system
- Marek Blok
- Sylwester Kaczmarek
- Magdalena Młynarczuk
2019 Pełny tekst Zeszyty Naukowe Akademii Marynarki Wojennej
The main task of the Polish Border Guard is protection of the country’s border which requires utilization of multimedia surveillance systems automatically gathering, processing and sharing various data. The paper presents such a system developed for the Maritime Division of the Polish Border Guard within the STRADAR project and the problem of fusion of radar data in this system. The system, apart from providing communication means, gathers data from AIS, GPS and radar receivers: ARPA and SCANTER 2001. In the paper the concept of the radar data gathering in STRADAR system is provided with detailed presentation of radar servers, Radar INT modules and a reduplication (fusion) module and the proposition of the algorithm for radar data fusion.
Radar Signal Parameters Estimation Using Phase Accelerogram in the Time-Frequency Domain
- Karol Abratkiewicz
- Piotr Samczyński
- Krzysztof Czarnecki
2019 IEEE SENSORS JOURNAL
Radar signal parameter estimation, in the context of the reconstruction of the received signal in a passive radar utilizing other radars as a source of illumination, is one of the fundamental steps in the signal processing chain in such a device. The task is also a crucial one in electronic reconnaissance systems, e.g. ELINT (Electronic Intelligence) systems. In order to obtain accurate results it is important to measure, estimate and precisely reconstruct the considered signal. Then it is necessary to identify it. The following paper presents a new approach to the estimation of the phase parameters of radar pulses. The novel method of chirp-rate estimation is described and used to analyze such signals. First, the method was examined by simulated pulses, and then true measured signals collected from an ATC (Air Traffic Control) radar were utilized. Using the phase accelerogram, an instantaneous chirp-rate was computed thanks to three novel estimators and the results were compared to results acquired using a different, already known, estimation method of the phase coefficients based on matching filtration – EGCT (Extended Generalized Chirp Transform).
Randomly Functionalized Polyethylenes: In Quest of Avoiding Catalyst Deactivation
- Lidia Jasińska-Walc
- Rob Duchateau
- Miloud Bouyahyi
- Younes Turki
- Akhilesh Tanwar
2019 ACS Catalysis
Well-defined randomly functionalized polyolefins produced by catalysis form an interesting class of polymers with great potential for various applications. One of the major challenges for the production of these materials forms the incompatibility of the commonly used electrophilic group 4 metal based catalysts and the desired nucleophilic, especially protic functionalities like hydroxyl and carboxylic acid groups. Although pacification of the protic functionality remains necessary, it was found that lowering the oxidation state of a constrained geometry type of catalyst from Ti(IV) to Ti(III) turned the catalyst unexpectedly tolerant to a wide variety of aluminum alkyl pacified, hydroxyl-functionalized olefin comonomers. The catalyst’s tendency to undergo chain transfer to aluminum, which was found to be intensified by the presence of aluminum alkyl pacified, hydroxyl-functionalized comonomers, can be efficiently suppressed by the addition of a sterically hindered phenol such as 2,6-bis(1,1-dimethylethyl)-4-methylphenol (BHT). Surprisingly, the addition of BHT also increases the catalyst’s affinity to incorporate these functionalized comonomers.
Ranking of Heterogeneous Catalysts Metals by Their Greenness
- Marta Bystrzanowska
- Petko Petkov
- Marek Tobiszewski
2019 Pełny tekst ACS Sustainable Chemistry & Engineering
Catalysis is very important process in industry and laboratory practice, especially from the point of green chemistry principles. However, eco-friendly character of heterogeneous catalysts, containing transition metal components has not been evaluated, yet. Therefore, we perform a comprehensive assessment of 18 heterogeneous metal catalysts (Pd, Pt, V, Co, Ni, Mo, Ru, Mn, Au, Cu, Cd, Zr, Fe, Rh, Ir, Sn, Zn, Ag) using multicriteria decision analysis approach. The ranking of alternatives according to relevant criteria like toxicity of pure metals and metal salts towards fish and Daphnia magna, algae/plants, metal toxicity towards rats via ingestion, carcinogenicity, the endangerment degree of metals, boiling point and energy for atom detachment, estimated as metal-metal bond strength in diatomic transition metal units, classification of elemental impurities according to International Conference on Harmonization (ICH)and their degree of importance is presented. Life cycle assessment (LCA) related parameters of metals have been also included. The assessment showed ruthenium, iron and molybdenum as the most favourable alternatives, in contrary to nickel, cobalt and rhodium. Results of environmental evaluation strictly depend on chosen scenario of assessment, in terms of toxicity, endangered elements or LCA. Sensitivity analyses towards variations in input data and applied weights, prove that results are reliable. Multicriteria decision analysis can be successfully applied in metal catalysts evaluation for particular case studies of different reactions.
Rapid Multi-band Patch Antenna Yield Estimation Using Polynomial Chaos-Kriging
- Xiaosong Du
- Leifur Leifsson
- Sławomir Kozieł
2019 Pełny tekst
Yield estimation of antenna systems is important to check their robustness with respect to the uncertain sources. Since the Monte Carlo sampling-based real physics simulation model evaluations are computationally intensive, this work proposes the polynomial chaos-Kriging (PC-Kriging) metamodeling technique for fast yield estimation. PC-Kriging integrates the polynomial chaos expansion (PCE) as the trend function of Kriging metamodel since the PCE is good at capturing the function tendency and Kriging is good at matching the observations at training points. The PC-Kriging is demonstrated with an analytical case and a multi-band patch antenna case and compared with direct PCE and Kriging metamodels. In the analytical case, PC-Kriging reduces the computational cost by around 42% compared with PCE and over 94% compared with Kriging. In the antenna case, PC-Kriging reduces the computational cost by over 60% compared with Kriging and over 90% compared with PCE. In both cases, the savings are obtained without compromising the accuracy.
Rapid multi-objective design of integrated on-chip inductors by means of Pareto front exploration and design extrapolation
- Sławomir Kozieł
- Piotr Kurgan
2019 JOURNAL OF ELECTROMAGNETIC WAVES AND APPLICATIONS
Identification of the best trade-offs between conflicting design objectives allows for making educated design decisions as well as assessing suitability of a given component or circuit for a specific application. In case of inductors, the typical objectives include maximization of the quality factor and minimization of the layout area, as well as maintaining a required inductance at a given operating frequency. This work demonstrates low-cost multi-objective design optimization of integrated inductors. The primary technique utilized here is a point-by-point Pareto front exploration where subsequent Pareto-optimal designs are obtained by moving along the front using local search methods. Considerable reduction of the design cost is achieved by extrapolating inductor dimensions at the subsequent optimal point, based on already available data as well as size constraints. The proposed methodology is verified using two examples of spiral inductors implemented in 65-nm CMOS technology. Comparisons with point-by-point optimization without extrapolation are also provided.
Rapid Re-Design and Bandwidth/Size Trade-Offs for Compact Wideband Circular Polarization Antennas Using Inverse Surrogates and Fast EM-Based Parameter Tuning
- Ullah Ubaid
- Sławomir Kozieł
- Ismail Mabrouk
2019 Pełny tekst IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION
Design of compact wideband circularly polarized (CP) antennas is challenging due to the necessity of simultaneous handling of several characteristics (reflection, axial ratio, gain) while maintaining a small size of the structure. Antenna re-design for various operating bands is clearly more difficult yet practically important because intentional reduction of the bandwidth (e.g., by moving the lower edge of the operating band up in frequency) may lead to a considerable size reduction, which can be beneficial for specific application areas. This paper proposes a rigorous approach to rapid re-design of miniaturized CP antennas involving inverse surrogate models and fast electromagnetic (EM)-based parameter tuning. Our methodology allows for a precise control of the lower operating frequency of the CP antenna (both in terms of the impedance and axial ratio bandwidth) and accomplishing the geometry parameter scaling at an extremely low cost of a few EM analyses of the structure at hand. Our methodology is demonstrated by re-designing a compact wide slot CP antenna in the range of 3.2 GHz to 5.8 GHz. The proposed approach can be used for fast rendering of the bandwidth/size trade-offs (the footprints obtained for the verification structure range from 783 mm2 to 482mm2), thus determining the most suitable designs for particular applications. The numerical findings are validated experimentally.
Reactivity study of a β-diketiminate titanium(III) complex with a phosphanylphosphido ligand towards chlorophosphanes. A new method of synthesis of β-diketiminate titanium(IV) complexes with versatile phosphanylphosphinidenes
- Aleksandra Ziółkowska
- Natalia Szynkiewicz
- Jerzy Pikies
- Łukasz Ponikiewski
2019 Pełny tekst POLYHEDRON
The reactivity of ab-diketiminate titanium(III) complex with a phosphanylphosphido ligand, [MeNacNacTi(Cl){g2-P(SiMe3)-PtBu2}] (1)(MeNacNac= [Ar]NC(Me)CHC(Me)N[Ar]; Ar = 2,6-iPr2Ph), was investigatedtowards selected chlorophosphanes, such astBu2PCl,iPr2PCl, Cy2PCl, (Cy)tBuPCl, (Me)tBuPCl, (Ph)tBuPCl, Ph2PCl, (iPr2N)tBuPCl and (Et2N)2PCl. The reactions withtBu2PCl and Ph2PCl lead mainly to theearlier described complex [MeNacNacTi(Cl){g2-P-PtBu2}] (1a), while the reactions withiPr2PCl, Cy2PCl,(Cy)tBuPCl, (Me)tBuPCl and (Ph)tBuPCl lead to mixtures of differentb-diketiminate titanium(IV) com-plexes with phosphanylphosphinidene ligands:1aand [MeNacNacTi(Cl){g2-P-PiPr2}] (1b),1aand[MeNacNacTi(Cl){g2-P-PCy2}] (1c),1aand [MeNacNacTi(Cl){g2-P-P(Cy)tBu}] (1d),1aand [MeNacNacTi(Cl){g2-P-P(Me)tBu}] (1e),1aand [MeNacNacTi(Cl){g2-P-P(Ph)tBu}] (1f) respectively. The newly obtainedcompounds1cand1dwere isolated and their identities unambiguously confirmed by X-ray diffraction,NMR spectroscopy and elemental analysis. In the reaction with (Et2N)2PCl the related titanium(IV) com-plex is not observed, but the phosphetanetBu2P-P(l2-PNEt2)2P-PtBu2(3) is formed
Reakcja miesięcznej i sezonowej temperatury powietrza na północnym skłonie Karkonoszy i ich przedpolu na zmiany wskaźnika NAO.
- Anna Styszyńska
- Krzysztof Migała
- Grzegorz Urban
2019
Przedstawiono wpływ wskaźnika NAO na kształtowanie temperatury powietrza w warunkach górskich na przykładzie Karkonoszy. Stwierdzono zmniejszanie się wpływu NAO na temperaturę powietrza ze wzrostem wysokości. Stwierdzono, że relacje między NAO a temperaturą powietrza są istotne jedynie w okresie zimowym od grudnia do marca włącznie. Związki te są niestacjonarne i wynikają ze wzrostu ciśnienia w Wyżu Azorskim w okresie 1988-2015. Modyfikuje on zmiany zachmurzernia i usłonecznienia w tym rejonie.
Real and Virtual Instruments in Machine Learning – Training and Comparison of Classification Results
- Maciej Blaszke
- Damian Koszewski
- Szymon Zaporowski
2019
The continuous growth of the computing power of processors, as well as the fact that computational clusters can be created from combined machines, allows for increasing the complexity of algorithms that can be trained. The process, however, requires expanding the basis of the training sets. One of the main obstacles in music classification is the lack of high-quality, real-life recording database for every instrument with a variety of musical articulation. This study aims not only to expand databases with samples prepared by using VSTs but also to verify quality of real-instrument signal classification, compared to signals created digitally. Also, the possibility of training an algorithm with real and additional synthetic data mixed is explored. In the paper, machine learning algorithms are described first. A way to generate an expanded training set and the classification process preparation is presented afterward. Then, the results are compared, and future work is outlined in conclusions.
Realizacja mobilnego urządzenia do wytwarzania kurtyny elektromagnetycznej do zastosowań specjalnych
- Piotr Rajchowski
- Krzysztof Cwalina
- Jarosław Magiera
- Alicja Olejniczak
- Paweł Kosz
- Agnieszka Czapiewska
- Robert Burczyk
- Krzysztof Kowalewski
- Jarosław Sadowski
- Sławomir Ambroziak
2019
In the article the assumptions, design and realisation of the technological demonstrator of a mobile device for generating an electromagnetic curtain (AEGIS) were presented, both in the area of hardware and software. The device is designed to block radio communication by which it is possible to detonate the Radio Controlled Improvised Explosive Devices (RCIEDs). The preliminary laboratory tests of the demonstrator for generating the jamming signal, that were presented in the paper, aimed at assessing the correctness of the device operation and generated signal parameters verification. On the basis of the obtained results, the ability to jam the cellular systems as well as other radio devices operating in the frequency band from 400 MHz to 2700 MHz was assessed.
Real-time hybrid model of a wind turbine with doubly fed induction generator
- Robert Rink
- Robert Małkowski
2019 Pełny tekst
In recent years renewable sources have been dominating power system. The share of wind power in energy production increases year by year, which meets the need to protect the environment. Possibility of conducting, not only computer simulation, but also laboratory studies of wind turbine operation and impact on the power system and other power devices in laboratory conditions would be very useful. This article presents a method of performing real-time hybrid model of a wind turbine. The advantage of a hybrid model is the combination of the possibilities and flexibility of simulation of aerodynamic and mechanical phenomena with the electric machine, which is seen from the point of view of the grid as a real wind turbine. The originality of the presented approach is using a real-time digital model to control a power device connected to the grid. Real-time simulation is performed of aerodynamic phenomena and conversion of wind energy for a mechanical moment on the shaft, which controls via a converter of asynchronous motor driving a doubly-fed induction generator. The hybrid model allows testing wind turbines in transient conditions after disturbances not feasible with physical wind. The paper describes the concept and the structure of a wind turbine hybrid model. Components of a wind turbine hybrid model are described. The results of laboratory studies of the real-time hybrid model of a wind turbine are presented.
Reasons behind changes in the share of labour in national income in the Polish economy: Selected aspects
- Małgorzata Gawrycka
- Anna Szymczak
2019 Pełny tekst Journal of Economics and Management
Aim/purpose – The aim of this paper is to examine the impact of structural changes taking place in the Polish economy on the share of labour in national income. Design/methodology/approach – The scope of this study includes a review of the literature dedicated to the issue and an empirical analysis of data available on this topic. The study uses elements of descriptive statistics and the method of induction. Findings – The conducted analysis shows that in the years 2005-2016, a relation contrary to that reported by de Serres, Scarpetta, & de la Maisonneuve (2002), concerning shifts of employee groups between sectors of the national economy, prevailed in Poland. No research results on the impact of the decrease in the share of self-employed on the decrease in the share of labour in the national income have been confirmed. At the same time, the effect of changes in the relation between employee remuneration and the added value, resulting from their transition between sectors of the national economy, was positively verified. Research implications/limitations – The results related to changes in the share of self- -employed in the national economy should be treated with caution, as there are also economically inactive entities listed in the Central Statistical Office (GUS) register. Originality/value/contribution – To date, in Poland comprehensive research into the influence of structural changes on the share of labour in national income has not been conducted.