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Publications Repository
Gdańsk University of Technology

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Publications from the year 2020

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  • Application of Diversity Combining with RLS Adaptive Filtering in Data Transmission in a Hydroacoustic Channel
    • Agnieszka Czapiewska
    • Ryszard Studański
    • Andrzej Łuksza
    • Andrzej Żak
    2020 Full text SENSORS

    When transmitting data in a hydroacoustic channel under difficult propagation conditions, one of the problems is intersymbol interference (ISI) caused mainly by the effect of multipath propagation. This phenomenon leads to a decrease in transmission parameters, and sometimes completely prevents it. Therefore, we have made an attempt to use diversity combining with Recursive Least Squares (RLS) adaptive filtering to improve the quality of data transmission in a hydroacoustic channel with strong reflections. The method was tested in simulation and during measurements in a real environment. The influence of the method on data transmission in the hydroacoustic channel was examined in detail. The obtained results allow us to draw conclusions regarding the purposefulness of use of diversity combining and RLS adaptive filtering in order to improve the quality of data transmission by reducing the effect of ISI.

  • Application of Least Squares with Conditional Equations Method for Railway Track Inventory Using GNSS Observations
    • Krzysztof Czaplewski
    • Zbigniew Wiśniewski
    • Cezary Specht
    • Andrzej Wilk
    • Władysław Koc
    • Krzysztof Karwowski
    • Jacek Skibicki
    • Paweł Dąbrowski
    • Bartosz Czaplewski
    • Mariusz Specht
    • Piotr Chrostowski
    • Jacek Szmagliński
    • Sławomir Judek
    • Sławomir Grulkowski
    • Roksana Licow
    2020 Full text SENSORS

    Satellite geodetic networks are commonly used in surveying tasks, but they can also be used in mobile surveys. Mobile satellite surveys can be used for trackage inventory, diagnostics and design. The combination of modern technological solutions with the adaptation of research methods known in other fields of science offers an opportunity to acquire highly accurate solutions for railway track inventory. This article presents the effects of work carried out using a mobile surveying platform on which Global Navigation Satellite System (GNSS) receivers were mounted. The satellite observations (surveys) obtained were aligned using one of the methods known from classical land surveying. The records obtained during the surveying campaign on a 246th km railway track section were subjected to alignment. This article provides a description of the surveying campaign necessary to obtain measurement data and a theoretical description of the method employed to align observation results as well as their visualisation.

  • Application of mesh deformation for modeling of conformal RF components with 3D FEM
    • Maciej Jasiński
    • Adam Lamęcki
    • Michał Mrozowski
    2020 Full text

    In this paper, a method of analysis of conformal RF components has been proposed. In this approach, modeling of a curved structure is based on mesh deformation of planar objects rather than the construction of conformal geometry at CSG level. Since the model is represented as a 3D mesh, the deformation only requires the calculation of nodes position in the bent structure. The results of the proposed algorithm have been validated with simulation from other software and measurements, whereby method correctness has been confirmed

  • Application of non-classical operational calculus to indicate hazards in numerical solutions of engineering problems
    • Eligiusz Mieloszyk
    • Mariusz Wyroślak
    2020 Full text Studia Geotechnica et Mechanica

    The article addresses the application of non- classical operational calculus to approximative solutions of engineering problems. The engineering-sound examples show that a continuous–discrete problem transformation from differential unequivocal problem to a differential wildcard problem, triggering a change in solution quality. A number of approximative methods are capable to alter both quantitative and qualitative solution effects.

  • Application of probabilistic tools to extend load test design of bridges prior to opening
    • Piotr Owerko
    • Karol Winkelmann
    • Jarosław Górski
    2020 Structure and Infrastructure Engineering

    Load tests of bridges are widely performed in a large number of countries. Deterministic comparison of measurement results to the theoretical, FEM (finite element method)-based outcomes with possible further calibration is mostly applied. Sometimes, the data collected in the tests are also used to calibrate the reliability factors of bridge structures or their components. This work proposes to complement the stage of the load test design with the use of probabilistic tools. This approach is intended to provide a reliable and trustworthy limit range of measured values (e.g. displacements) instead of restrictive single values, streamlining the performance of in-situ tests. The proposed procedure is supported by an arch bridge example with the following uncertainty sources: random imperfections of the arch girder, random stiffness of the deck and random total weight of the applied load trucks. The presented calculations refer to global structural stiffness assessment. Both point estimate method (PEM) and response surface method (RSM) are applied here. It has been shown that the proposed procedure effectively supplements the deterministic approach, thus the suggested extension of application of probabilistic tools to bridge load test design is innovative and justified.

  • Application of safirinium N-hydroxysuccinimide esters to derivatization of peptides for high-resolution mass spectrometry, tandem mass spectrometry, and fluorescent labeling of bacterial cells
    • Joanna Fedorowicz
    • Magdalena Wierzbicka
    • Marek Cebrat
    • Paulina Wiśniewska
    • Rafał Piątek
    • Beata Zalewska-Piątek
    • Zbigniew Szewczuk
    • Jarosław Sączewski
    2020 Full text INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES

    Mass spectrometry methods are commonly used in the identification of peptides and biomarkers. Due to a relatively low abundance of proteins in biological samples, there is a need for the development of novel derivatization methods that would improve MS detection limits. Hence, novel fluorescent N-hydroxysuccinimide esters of dihydro-[1,2,4]triazolo[4,3-a]pyridin-2-ium carboxylates (Safirinium P dyes) have been synthesized. The obtained compounds, which incorporate quaternary ammonium salt moieties, easily react with aliphatic amine groups of peptides, both in solution and on the solid support; thus, they can be applied for derivatization as ionization enhancers. Safirinium tagging experiments with ubiquitin hydrolysate revealed that the sequence coverage level was high (ca. 80%), and intensities of signals were enhanced up to 8-fold, which proves the applicability of the proposed tags in the bottom-up approach. The obtained results confirmed that the novel compounds enable the detection of trace amounts of peptides, and fixed positive charge within the tags results in high ionization efficiency. Moreover, Safirinium NHS esters have been utilized as imaging agents for fluorescent labeling and the microscopic visualization of living cells such as E. coli Top10 bacterial strain.

  • Application of Shape Memory Alloys in Pipeline Couplings for Shipbuilding
    • Leszek Matuszewski
    2020 Full text Polish Maritime Research

    The aim of the study is to analyse shape memory alloy (SMA) pipeline joints in limited space applications for all kinds of ships. Generally, the space available in various areas on ships is strictly limited and service works usually meet many obstacles. If we consider a pipeline, the flange joints always require a larger free space around the pipe than the pipe alone. A simultaneous problem can occur with the propeller shaft line coupling between bearings. SMA couplings require less space around the pipe and service should be easier, e.g., insulation fixing, painting and so on. SMA couplings last for a lifetime and there is no need for periodical seal replacement. Herein, some proposals among other unpublished data are discussed. There is a significant technological interest in the use of SMAs for applications not widely used yet. A wide variety of alloys present the shape memory effect and many generate an expressive restitution force considerable for commercial interests.

  • Application of sliding switching functions in backstepping based speed observer of induction machine
    • Marcin Morawiec
    • Arkadiusz Lewicki
    2020 IEEE TRANSACTIONS ON INDUSTRIAL ELECTRONICS

    The paper presents an analysis of the speed observer which is based on the backstepping and sliding mode approach. The speed observer structure is based on the extended mathematical model of an induction machine. The observer structure is based on the measured phase stator currents and transformed to ( αβ ) coordinate system. The stator voltage vector components are treated as known values. Additionally, such an observer structure is extended to the integrators. The observer stabilizing functions contain the appropriate sliding surfaces which result from Lyapunov function. The rotor angular speed is obtained from non-adaptive dependence. Stability analysis of the observer structure based on Lyapunov theory is presented in order to guarantee the estimation errors decay to zero.

  • Application of Stirling Engine Type Alpha Powered by the Recovery Energy on Vessels
    • Jacek Kropiwnicki
    2020 Full text Polish Maritime Research

    The Stirling engine is a device, in which thermal energy is transformed into mechanical without a contact between the heat carrier, and the working gas closed in the engine. Mentioned feature makes this type of engine very attractive for the use of the recovery energy, taken from other heat devices. One of the potential applications of Stirling engines is the use of thermal energy generated in the ship's engine room for producing electricity. The work presents the concept of the Stirling engine type alpha powered by the recovery energy. The model of Stirling engine developed in this work allows a quantitative assessment of the impact of the design features of the engine, primarily the heat exchange surfaces and the volume of control spaces, on the achieved efficiency and power of the engine. Using the iterative procedure, the Stirling engine simulation tests were carried out taking into account the variable structural features of the system. The influence of the size of the heater and the cooler, as well as, the effectiveness of the regenerator and the temperature of the heat source on the efficiency and power produced by the Stirling engine have been presented.

  • Application of surface active amino acid ionic liquids as phase-transfer catalyst
    • Emil Szepiński
    • Patrycja Smolarek
    • Maria Milewska
    • Justyna Łuczak
    2020 JOURNAL OF MOLECULAR LIQUIDS

    Five structurally related morpholinium derived ionic liquids containing N-acetyl-glycinate anion were synthesized and their thermal stability, surface properties and activity as phase transfer catalysts investigated. The thermal properties were studied by differential scanning calorimetry, while the adsorption at the air/water interface and micellization behavior was analyzed by surface tension measurements, conductometry and isothermal titration calorimetry. The catalytic activity was assessed in two model reactions that were N-alkylation of dibenzoazepine and C-alkylation reaction of fluorene derivatives. The effect of the chain length, thus surface activity of the newly synthetized ionic liquids on the yields of N- and C-alkylation reactions was discussed.

  • Application of the Anammox Process for Treatment of Liquid Phase Digestate
    • Joanna Majtacz
    • Dominika Grubba
    • Krzysztof Czerwionka
    2020 Full text Water

    The liquid phase of the digestate (LPD) contains a relatively high concentration of nitrogen, with total ammonium nitrogen being the dominant form of nitrogen, as well as other essential nutrients such as phosphorus and potassium. Consequently, it must be treated before it is released into the environment. However, there are no reports of co-purification of LPD in the anammox process in sequencing batch reactor with granular sludge, which is a novelty for the presented research. The main objective of this paper is to assess the possibility of nitrogen removal in the anammox process with LPD from biogas plants conducting the co-fermentation process along with the participation of agricultural products (cattle slurry). This publication presents the research results of the efficiency of the anammox process, accounting for the effect of dissolved organic matter. The conducted experiments revealed the potential of LPD purification, which co-ferments waste activated sludge and bovine slurry for the anammox process. In the reactor ammonium utilization rate (AUR) process with LPD addition increased from 2.3 mg N/(g VSS∙h) with 0.5% LPD addition to 8.5 mg N/(g VSS∙h) with 7.5% LPD addition. SAA in the reactor with LPD addition increased from 5.3 mg N/(g VSS∙h) with 0.5% LPD addition to 18.5 mg N/(g VSS∙h) with 4 and 5% LPD addition. With the addition of 7.5% LPD, SAA dropped to a value of 18.1 mg N/(g VSS∙h) in the LPD reactor.

  • Application of the Chimney Cap as a Method of Improving the Effectiveness of Natural Ventilation in Buildings
    • Romana Antczak-Jarząbska
    • Maciej Niedostatkiewicz
    2020 Full text Polish Maritime Research

    Adequately designed natural ventilation is the cheapest and easiest way to effectively remove indoor pollutants and keep the air inside a building fresh. A prediction of the performance and effectiveness of ventilation in order to determine the design of a ventilation system can provide real and long-term cost savings. The worst time in terms of the efficiency of natural ventilation is the spring-autumn transition period [7]. In order to improve the efficiency of natural ventilation, chimney caps are used, among others. They are designed to improve the chimney effect described in colloquial language as a chimney draft. The chimney effect is a physical phenomenon of the formation of a spontaneous flow of a warmer gas, e.g. air, from the bottom up in stem channels [12]. The article analyses the influence of the chimney cowl on the improvement of the chimney effect in an apartment of a multi-family building with natural ventilation. Long-term tests of the chimney draft were carried out for the case without and with a chimney cap. The paper presents the results of the performance (air change rate, ACH) of natural ventilation for a building with an inlet gap measured for the transitional season (between the heating and the summer season). The measurements were performed during a windy period.

  • APPLICATION OF THE GWR MODEL FOR PREDICTING THE ROAD FATALITIES RATE ON THE ROAD NETWORK IN THE NUTS 3 REGIONS IN EUROPE ON THE EXAMPLE OF KUYAVIAN- -POMERANIAN VOIVODESHIP
    • Joanna Wachnicka
    • Katarzyna Palikowska
    2020 Full text Journal of KONBiN

    The article presents the application of the GWR (Geographically Weighted Regression) model to the description of differences in the level of road traffic safety in individual counties on the example of the Kuyavian-Pomeranian Voivodeship. The GWR model developed for counties, taking into account the diversity of NUTS 3 regions, can be a helpful tool for traffic safety management in voivodships and lower administrative units, and such an approach has not yet been applied.

  • Application of the LifeRoSE method in funcionality evaluation of road safety equipment
    • Anna Gobis
    • Kazimierz Jamroz
    • Łukasz Jeliński
    2020 Full text Journal of KONBiN

    The article presents a mathematical model of the life cycle estimation method of road safety equipment. Then the model was adjusted to estimate the life cycle costs of the chosen horizontal road marking. Using the LCC method, the functionality of the horizontal marking was evaluated in terms of efficiency, durability and economic effectiveness. The article also presents the impact of selected factors on the life cycle costs of the horizontal road marking

  • Application of the Monte Carlo algorithm for solving volume integral equation in light scattering simulations
    • Maciej Kraszewski
    • Jerzy Pluciński
    2020 Full text OPTICA APPLICATA

    Various numerical methods were proposed for analysis of the light scattering phenomenon. Important group of these methods is based on solving the volume integral equation describing the light scattering process. The popular method from this group is the discrete dipole approximation (DDA). DDA uses various numerical algorithms to solve the discretized integral equation. In the recent years, the application of the Monte Carlo (MC) algorithm as one of them was proposed. In this research, we analyze application of the MC algorithm for two cases: the light scattering by large particles and by random conglomerates of small particles. We show that if proper preconditioning of the numerical problem is applied, the MC algorithm can solve the underlying systems of linear equations. We also show that the efficiency of the MC algorithm can be increased by reusing performed computations for various incident electromagnetic waves and the applicability of the MC algorithm depends on the particular use case. It is unlikely to be used in the case of light scattering by the large particles due to computational times inferior comparing with the other numerical methods but may become useful in the case of light scattering by the random conglomerates of small scattering particles.

  • Application of the neural networks for developing new parametrization of the Tersoff potential for carbon
    • Anthony Chukwuemeka Nwachukwu
    • Szymon Winczewski
    2020 Full text TASK Quarterly

    Penta-graphene (PG) is a 2D carbon allotrope composed of a layer of pentagons having sp2- and sp3-bonded carbon atoms. A study carried out in 2018 has shown that the parameterization of the Tersoff potential proposed in 2005 by Ehrhart and Able (T05 potential) performs better than other potentials available for carbon, being able to reproduce structural and mechanical properties of the PG. In this work, we tried to improve the T05 potential by searching for its parameters giving a better reproduction of the structural and mechanical properties of the PG known from the ab initio calculations. We did this using Molecular Statics (MS) simulations and Neural Network (NN). Our test set consisted of the following structural properties: the lattice parameter a; the interlayer spacing h; two lengths of C-C bonds, d1 and d2 respectively; two valence angles, 1 and 2, respectively. We also examined the mechanical properties by calculating three elastic constants, C11, C12 and C66, and two elastic moduli, the Young’s modulus and the Poisson’s ratio . We used MS technique to compute the structural and mechanical properties of PG at = 0 K. The Neural Network used is composed of 2 hidden layers, with 20 and 10 nodes for the first and second layer, respectively. We used an Adams optimizer for the NN optimization and the Mean Squared Error as the loss function. We obtained inputs (about 80 000 different sets of potential parameters) for the Molecular Statics simulation by using randomly generated numbers. The outputs from these simulations became the inputs to our Neural Network. The Molecular Statics simulations were done with LAMMPS while the Neural Network and other computations were done with Python, Pytorch, Numpy, Pandas, GNUPLOT and Bash scripts. We obtained a parameterization which has a slightly better accuracy (lower relative errors of the calculated structural and mechanical properties) than the original parameterization.

  • Applying artificial neural networks for modelling ship speed and fuel consumption
    • Wiesław Tarełko
    • Krzysztof Rudzki
    2020 Full text NEURAL COMPUTING & APPLICATIONS

    This paper deals with modelling ship speed and fuel consumption using artificial neural network (ANN) techniques. These tools allowed us to develop ANN models that can be used for predicting both the fuel consumption and the travel time to the destination for commanded outputs (the ship driveline shaft speed and the propeller pitch) selected by the ship operator. In these cases, due to variable environmental conditions, making decisions regarding setting the proper commanded outputs to is extraordinarily difficult. To support such decisions, we have developed a decision support system. Its main elements are the ANN models enabling ship fuel consumption and speed prediction. To collect data needed for building ANN models, sea trials were conducted. In this paper, the decision support system concept, input and variables of the ship driveline system models, and data acquisition methods are presented. Based on them, we developed appropriate ANN models. Subsequently, we performed a quality assessment of the collected data set, data normalization and division of the data set, selection of an ANN model architecture and assessment of their quality.

  • Applying case studies to teaching architectural investment
    • Michał Kwasek
    • Rafał Janowicz
    2020 Full text World Transactions on Engineering and Technology Education

    Case studies enable students to encounter practical issues during their education. Experiments conducted in class employing this method often feature simplified models of real-world situations. However, they still enable students to encounter actual problems, to which theoretical knowledge is applied. In architectural education, students carrying out semester projects usually rely on data provided by the teacher, without wondering where the data came from. The case study method described here was implemented by means of a graph and in accordance with the principles of turquoise teaching. It has been implemented and used for several years in classes, where architecture students are taught how to manage their company and how to organise the investment process. The teaching covers essential guidelines that determine how the architect-manager works. Discussed in this article are the advantages of the method, the impact of it on the effectiveness of education and its application.

  • Approximation of Fractional Order Dynamic Systems Using Elman, GRU and LSTM Neural Networks
    • Bartosz Puchalski
    • Tomasz Rutkowski
    2020 Full text

    In the paper, authors explore the possibility of using the recurrent neural networks (RNN) - Elman, GRU and LSTM - for an approximation of the solution of the fractional-orders differential equations. The RNN network parameters are estimated via optimisation with the second order L-BFGS algorithm. It is done based on data from four systems: simple first and second fractional order LTI systems, a system of fractional-order point kinetics and heat exchange in the nuclear reactor core and complex nonlinear system. The obtained result shows that the studied RNNs are very promising as approximators of the fractional-order systems. On the other hand, these approximations may be easily implemented in real digital control platforms.

  • Aptamer based tools for environmental and therapeutic monitoring: A review of developments, applications, future perspectives
    • Błażej Kudłak
    • Monika Wieczerzak
    2020 Full text CRITICAL REVIEWS IN ENVIRONMENTAL SCIENCE AND TECHNOLOGY

    Nucleic acids in the form of aptamers play a growing and significant role in the targeted and rapid analysis of environmental sample composition and medical analyses. In this paper, the review of both aptamers synthesis methods as well as application of these short chain oligonucleotides (with critical comments on their strong and weak features) are given. The first ones include: systematic evolution of ligands by exponential enrichment (SELEX), high throughput aptamer identification screen (HAPIscreen), and a non-equilibrium capillary electrophoresis of equilibrium mixture (NECEEM). Afterwards, manuscript describes variety of sensors and biotests utilizing aptamers as active part of its action starting from electrochemical aptasensors, through optical to piezo-electric ones. Described biotests present basic developments in enzymelinked apta-sorbent assays (ELASA) that can be performed with different variations (enzyme-linked aptamer assay (ELAA), enzyme-linked oligonucleotide assay (ELONA) and aptamerlinked immobilized sorbent assay (ALISA)). Next, the review presents advantages and drawbacks of recent aptameric developments in versatile laboratory applications, namely medical ones, as well as analytical and bioassays. Utilitarian development of aptasensors and aptamers would strongly benefit from an assembly of interdisciplinary teams containing chemists, physicists, biologists, medical doctors, and material and electronic scientists, to determine the most effective application methodologies.