2018 - Repozytorium publikacji - Politechnika Gdańska

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Impact of selected parameters of the fermentation process of wine and wine itself on the biogenic amines content: Evaluation by application of chemometric tools
- Justyna Płotka-Wasylka
- Vasil Simeonov
- Calum Morrison
- Jacek Namieśnik
2018 MICROCHEMICAL JOURNAL
The demand for safer foods has promoted more research into biogenic amines (BAs) over the past few years, however, there are still some questions that remain unanswered. Despite the fact that BAs are present in wine and can cause toxic effect to the body, a shared regulation limiting the amounts of BAs in wine is still lacking. A detailed understanding of their presence in wine is also important for the food trade sector. Therefore, the aim of this work was to determine the level of selected BAs in wine samples origin from Poland. Thereafter, the evaluation of correlation between concentration of BAs and selected parameters including pH, alcohol content and fermentation temperature by application of chemometric analysis was carried out. The BAs were determined by application of previously developed SPME-GC–MS methodology characterized by low detection limits ranged from 0.009 μg/L (tyramine) to 0.155 μg/L (histamine). Data obtained in this study show that none of the wine samples surpassed the toxic levels reported for BAs in the literature (the total BAs content was ranged from 7 to 2174 μg/L), therefore, these wines appear to be safe as regards the risk associated with the intake of potentially toxic BAs. Moreover, several correlations between occurrence, concentration of biogenic amines, important factors of winemaking process as well as physico-chemical parameters of wine were indicated. Even though information on BAs is currently not included in wine composition databases, information on their existence, distribution, concentration and knowledge of existing relationships between BAs and other wine parameters is crucial and may be useful for the food industry, health professionals and consumers.
Impact of Shifting Time-Window Post-Processing on the Quality of Face Detection Algorithms
- Adam Blokus
- Henryk Krawczyk
2018
We consider binary classification algorithms, which operate on single frames from video sequences. Such a class of algorithms is named OFA (One Frame Analyzed). Two such algorithms for facial detection are compared in terms of their susceptibility to the FSA (Frame Sequence Analysis) method. It introduces a shifting time-window improvement, which includes the temporal context of frames in a post-processing step that improves the classification quality. Error measures are proposed to express the frame-wise accuracy of classifying algorithms, as well as the segmentation of the result sequences which they produce. The two compared algorithms, after applying the FSA improvement, perform better in terms of all the considered measures. The performed experiments have allowed to draw conclusions regarding preferred methods of measuring accuracy of such algorithms and the selection of suitable classification algorithms for being improved. In the end of the work, the resulting future possibilities of further developing the FSA methods are noted.
Impact of the glazed roof on acoustics of historic interiors
- Andrzej Kulowski
2018
The paper discusses the adverse acoustic phenomena occurring in the semi-open interiors (courtyards, yards) covered with a glass roof. Particularly negative is the rever-beration noise, which leads to the degradation of the utility functions of the resulting spaces. It involves the drastically reducing the intelligibility of speech, loss of natural sounding of music, problems with the sound system, as well as disturbances in the voice alarm system operation. The work refers to historic interiors, where preservation requirements signifi-cantly limit the possibility to reduce reverberation noise by means of sound-absorbing materials of general use. The work describes the concept of the use of micro-perforated foil which is a modern, technologically advanced sound-absorbing material. Because of its high acoustical efficiency and negligible effect on the expression of architectural de-sign, micro-perforated foil is particularly suitable for the purpose in question.
Impact resistance of plain and twill fabric in GFRP measured by active thermography
- Gabriel Strugała
- Michał Landowski
- Maciej Zaremba
- Jarosław Turowski
- Marek Szkodo
2018 ADVANCED COMPOSITES LETTERS
This paper discusses the impact resistance of glass-fibre reinforced polymer (GFRP) composites depending on the type of reinforcement – plain or twill weave. The values of impact energy were: 3J, 10J and 15J. Specimens featuring twill weave transferred higher force during the impact as compared with plain weave specimens. It was observed that an increase of impact energy was accompanied by an increase of the disproportion in transferred forces, in favour of twill weave specimens. Impact damage (in both types of weave) occurring as a result of 3J impact was undetectable with active thermography method. The damage area measured by means of active thermography for impact energy values equal to 10J and 15J proved that the type of reinforcement significantly influences the impact resistance of a composite.This has been justified by smaller damage areas with high spot intensity of damage in plain weave specimens and highly dispersed damage with lower intensity in twill weave specimens.
Impacts in case of triple unilaterally constrained system
- Krzysztof Lipiński
2018
The this paper focus on the behaviour of a “rigid” body biting into another “rigid” body, with some nonzero relative velocity. In the presently considered case, the introduced collision appears between a selected element of a multibody structure and its reference body being interpreted as the motionless ground. Instead of the classic case, described in a number of dissertations, where a single impacting contact is considered, three unilateral contacts are considered simultaneously. Impacting bodies are considered as rigid (non-deformable). According to it, all impact periods are considered as infinitesimally short. As a consequence, some simplifications are possible in integrations performed during the impact period. Position can be considered as constant. Non-impact forces (gravity, joint actuation forces) can be neglected. Velocity quadratic inertia terms can be neglected, too. Only the velocity changes have to be evaluated. It can be done with use of the mass matrix and the contact forces, only. As it is detailed in the paper, in some of the considered cases, solution of a linear system of equations can be used instead of the integration. In the present test, a three unilateral contact points are considered, simultaneously. The main body of the system is at rest and it is supported at two unilateral contact points. As the mass of the main body is relatively high, these two contacts are preserved during all the pre-impact period of calculation. An additional arm is attached to the main body and it rotates at a high speed. It impacts the ground. It effects in a third contact point that appears simultaneously with the two previous contacts. Extending the classic conclusion formulated for the single impact cases, post impact velocities can be calculated with use of the linear system of equations. Such hypothesis is taken under verification in the paper. The numerical tests have disproved this hypothesis. Performed calculations have verified that classic method formulated for a single impact does not give the correct results, now. Post impact velocities of the system elements depend not only on the initial velocities of the impacting elements, but on the characteristics of the elastic and the damping properties of the contacting regions, too.
Impedance evaluation of coatings from biobased material
- Michał Szociński
- Kazimierz Darowicki
2018 Pełny tekst Surface Innovations
The authors propose a modification of sodium caseinate edible coating for foodstuff protection. The aim was to improve the film’s barrier properties. It was achieved by the addition of propolis, which is a natural, environmentally friendly product known from its intrinsic sealing action. In the next step, propolis-admixed sodium caseinate films were exposed to elevated temperature for 10 min. This approach was meant to improve the barrier effect of propolis. Electrochemical impedance spectroscopy was used to evaluate the performance of the control and modified samples upon immersion in water. Atomic force microscopy-based measurements visualised the sealing effect of propolis by means of topographical images, local direct-current maps and local impedance spectra of the control and modified films. From the obtained results the authors drew the conclusion that the proposed modifications improved the barrier properties of the sodium caseinate films. Applied combination of the investigation methods, electrochemical impedance spectroscopy and atomic force microscopy, allowed successful characterisation of protective properties of sodium caseinate coatings. The proposed atomic force microscopy measurement modes can be employed for evaluation of modifications implemented into biobased coatings, particularly when there is a need for electrolyteless tests.
Implementacja metody dojrzałości do oceny wytrzymałości betonu przęsła mostu extradosed
- Aleksandra Kuryłowicz-Cudowska
- Marzena Kurpińska
- Krzysztof Wilde
- Jacek Chróścielewski
2018
Artykuł przedstawia wybrane informacje dotyczące metody dojrzałości z odniesieniem się do niektórych dokumentów normatywnych polskich i zagranicznych. Przedstawione są także informacje o urządzeniach stosowanych in situ do oceny wczesnej wytrzymałości betonu. Praca poświęcona jest implementacji monitoringu dojrzewania betonu wysokowartościowego (C 60/75) wbudowanego w przęsło mostu extradosed z zastosowaniem metody dojrzałości. Publikacja ta powstała po zakończeniu wszystkich etapów badań na obiekcie, zatem wypracowane rezultaty uwzględniają wyniki badań laboratoryjnych, polowych i numerycznych. Badany obiekt to największy most typu extradosed w Europie pod względem rozpiętości przęsła. Projekt technologiczny budowy mostu zakładał podział ustroju na sekcje montażowe, betonowane technologią nawisową, dla których założono konkretne czasookresy wykonywania. Z uwagi na znaczny zakres i czas trwania inwestycji, niezbędne było zastosowanie alternatywnej metody do oceny wytrzymałości betonu na ściskanie bazującej na funkcji dojrzałości. Na podstawie opisu matematycznego, symulacji numerycznych i stworzonych procedur obliczeniowych dane z monitoringu posłużyły do oszacowania wytrzymałości betonu in situ. W efekcie sformułowano wskazówki dotyczące właściwej pielęgnacji betonu i określono możliwe terminy rozpoczęcia procesu sprężania konstrukcji, co przyczyniło się do skrócenia cyklu roboczego i przyspieszenia harmonogramu prac.
Implementacja w FPGA algorytmu detekcji krawędzi obrazu w czasie rzeczywistym
- Paweł Kowalski
- Robert Smyk
2018 Pełny tekst Zeszyty Naukowe Wydziału Elektrotechniki i Automatyki Politechniki Gdańskiej
W artykule przedstawiono projekt architektury oraz implementację układową toru przetwarzania wstępnego obrazu z modułem detekcji krawędzi. Układ został zaimplementowany w FPGA Intel Cyclone. Zrealizowany moduł wykorzystuje pięć wybranych algorytmów wykrywania krawędzi, w tym Robertsa, Sobela i Prewitt.
Implementation of DEIS for reliable fault monitoring and detection in PEMFC single cells and stacks
- Kazimierz Darowicki
- Ewa Janicka
- Michał Mielniczek
- Artur Zieliński
- Łukasz Gaweł
- Jens Mitzel
- Jurgen Hunger
2018 Pełny tekst ELECTROCHIMICA ACTA
Dynamic Electrochemical Impedance Spectroscopy (DEIS) was presented as novel method for diagnostic and monitoring of PEMFC stack and single cells operation. Impedance characteristics were obtained simultaneously with current - voltage characteristics for stack and each individual cell. Impedance measurements were performed in galvanodynamic mode. It allowed to compare performance of each cell and identification of faulty cell operation for activation, ohmic and mass transfer losses regions. The biggest difference in impedance value between healthy and faulty cell was registered for mass transfer losses region. The authors discussed the statistical selection of an equivalent circuit based on the course of χ2 value in the function of current.
Implementation of multicriteria decision analysis in design of experiment for dispersive liquid-liquid microextraction optimization for chlorophenols determination
- Paulina Bigus
- Jacek Namieśnik
- Marek Tobiszewski
2018 JOURNAL OF CHROMATOGRAPHY A
A novel and efficient approach to optimization of extraction step prior the chromatographic determination of nine chlorinated phenols is described. It is based on the combination of design of experiments and multicriteria decision analysis. Such an approach is used to optimize dispersive liquid-liquid microextraction procedure for the determination of 9 chlorophenols in water samples. Three parameters are optimized – sample volume, volume of disperser solvent and extraction solvent. Combination of the technique for order of preference by similarity to ideal solution with central composite design allows to perform multi-analyte procedure optimization. It gives information about the efficiency of the system for every experimental plan point in terms of closeness to ideal solution. The optimal conditions for extraction of chlorophenols are 76 μL of extraction solvent, 0.6 mL of dispersive solvent and 6.7 mL of water sample. The presented approach has the potential to be applied in variety of optimization systems.
Implementation of multi-operand addition in FPGA using high-level synthesis
- Robert Smyk
- Maciej Czyżak
2018 Pełny tekst Przegląd Elektrotechniczny
The paper presents the results of high-level synthesis (HLS) of multi-operand adders in FPGA using the Vivado Xilinx environment. The aim was to estimate the hardware amount and latency of adders described in C-code. The main task of the presented experiments was to compare the implementations of the carry-save adder (CSA) type multi-operand adders obtained as the effect of the HLS synthesis and those based on the basic component being 4-operand adder with fast carry-chain available in FPGA’s implemented in Verilog. However, the HLS synthesis simplifies the design and prototyping process but the received results indicate that the circuit obtained as the result of such synthesis requires twice more resources and is slower than its counterpart design using Verilog.
Implementation of Solute Transport in the Vadose Zone into the “HYDRUS Package for MODFLOW”
- Sahila Beegum
- Jiří Šimůnek
- Adam Szymkiewicz
- K Sudheer
- Indumathi Nambi
2018 GROUND WATER
The “HYDRUS package for MODFLOW” is an existing MODFLOW package that allows MODFLOW to simultaneously evaluate transient water flow in both unsaturated and saturated zones. The package is based on incorporating parts of the HYDRUS‐1D model (to simulate unsaturated water flow in the vadose zone) into MODFLOW (to simulate saturated groundwater flow). The coupled model is effective in addressing spatially variable saturated‐unsaturated hydrological processes at the regional scale. However, one of the major limitations of this coupled model is that it does not have the capability to simulate solute transport along with water flow and therefore, the model cannot be employed for evaluating groundwater contamination. In this work, a modified unsaturated flow and transport package (modified HYDRUS package for MODFLOW and MT3DMS) has been developed and linked to the three‐dimensional (3D) groundwater flow model MODFLOW and the 3D groundwater solute transport model MT3DMS. The new package can simulate, in addition to water flow in the vadose zone, also solute transport involving many biogeochemical processes and reactions, including first‐order degradation, volatilization, linear or nonlinear sorption, one‐site kinetic sorption, two‐site sorption, and two‐kinetic sites sorption. Due to complex interactions at the groundwater table, certain modifications of the pressure head (compared to the original coupling) and solute concentration profiles were incorporated into the modified HYDRUS package. The performance of the newly developed model is evaluated using HYDRUS (2D/3D), and the results indicate that the new model is effective in simulating the movement of water and contaminants in the saturated‐unsaturated flow domains.
Implementation of the FOPID Algorithm in the PLC Controller - PWR Thermal Power Control Case Study
- Bartosz Puchalski
- Tomasz Adam Rutkowski
- Kazimierz Duzinkiewicz
2018 Pełny tekst
In the paper authors describe proposition of design and verification procedures of the discrete Fractional Order PID (FOPID) algorithm for control of the Pressurized Water Reactor (PWR) thermal power near its nominal operating point. The FOPID algorithm synthesis consists of: off-line optimal tunning of its parameters in continuous time-domain with LQ (Linear Quadratic) performance index and simplified models of nuclear reactor and control rods drive; its transformation into equivalent integer order structure with Oustaloup filters; and finally its transformation into equivalent discrete form. Discrete FOPID algorithm is further implemented in the PLC controller and verified by real-time simulation in the Hardware In the Loop (HIL) structure with non-linear nuclear reactor model. Promising simulation results were obtained, which confirm improved flexibility of the discrete FOPID algorithm in comparison to its classical PID counterpart.
Implementing SP4CE Learning Rooms concept and AUTODESK online certification in the preparation of a new generation of engineers.
- Anna Czaja
2018 Pełny tekst
In academia, educators do not always cope with rapidly changing technologies. Yet keeping up with new trends is essential to graduates’ success in a competitive job market. In the article, the author will answer the question of how Autodesk University Open Educational Resources and Certiport exams including GMetrix can enhance students’ academic progress and prepare them for future career. The concept of co-operation between Authorized Autodesk Training Centre at Gdansk University of Technology and Faculty of Management and Economics will be proposed based on experiences gathered in the ERASMUS+ SP4CE project.
Implicit Space Mapping for Variable-Fidelity EM-Driven Design of Compact Circuits
- Sławomir Kozieł
- Adrian Bekasiewicz
2018 Pełny tekst IEEE Antennas and Wireless Propagation Letters
Space mapping (SM) belongs to the most successful surrogate-based optimization (SBO) methods in microwave engineering. Among available SM variations, implicit SM (ISM) is particularly attractive due to its simplicity and separation of extractable surrogate model parameters and design variables of the circuit/system at hand. Unlike other SM approaches, ISM exploits a set of preassigned parameters to align the surrogate with the high-fidelity EM model. However, application of ISM is challenging if equivalent network model of the structure is unavailable or of poor quality. In this letter, a modified ISM that exploits variable-fidelity EM simulation models is proposed. Here, preassigned parameters are introduced in the coarsely discretized EM surrogate by dividing the substrate below selected components of the structure into segments with different permittivity and common thickness. The proposed method has been verified (also experimentally) using a rat-race coupler and favorably compared with state-of-the-art SBO methods.
Import Intensity of Production, Tasks and Wages: Microlevel Evidence for Poland.
- Aleksandra Parteka
2018 Pełny tekst Entrepreneurial Business and Economics Review
Objective: This article relates to recent literature on labour market consequences of production fragmentation within Global Value Chains, analysed in the presence of workers’ heterogeneity and differences in the task content of jobs. The main aim is to assess if there is a relationship between wages of Polish workers and the degree of Polish production dependence on imported inputs. Research Design & Methods: Using microdata from EU-SILC on workers from Poland observed in 2008-2014, we estimate a Mincerian model, augmented by a measure of task content of occupations and the industry level index of the import intensity of production computed with input-output data and accounting for good’s production sequence). IV estimation is employed to account for potential endogeneity between the import intensity of production and wages. Findings: Regression results suggest that negative relationship between wages of Polish workers and the dependence of their sector of employment on foreign inputs is magnified by the routinisation level of the occupation. Hence occupation-specific task requirements play a role. Implications & Recommendations: It implies that not all the Polish workers are affected in the same. The movements towards jobs with higher degree of non-routine content could protect against negative wage effects of fragmentation. Contribution & Value Added: The relationship between wages in Poland and the reliance on foreign inputs and GVCs links has not yet been studied from the micro-level task-based perspective. This article fills in this gap.
Improved Performance of 1-Ethyl-3-Methylimidazolium Tetrafluoroborate at Steel/HCl Interface by Iodide Ions
- Husnu Gerengi
- Moses Solomon
- Saviour Umoren
- H Ugras
- Mesut Yildiz
- Paweł Ślepski
2018 Journal of Bio- and Tribo-Corrosion
The corrosion and corrosion inhibition of St37 steel in 0.1 M HCl solution by 1-ethyl-3-methylimidazolium tetrafluoroborate (EMITFB) and the effect of addition of KI on the inhibitive performance of EMITFB have been examined by electrochemical [electrochemical impedance spectroscopy, potentiodynamic polarization, and dynamic electrochemical impedance spectroscopy (DEIS)] and surface examination [scanning electron microscope (SEM) and energy-dispersive X-ray spectroscopy (EDS)] techniques. Results show that EMITFB could only afford the protection of St37 steel in HCl medium on an average scale. The highest studied concentration of EMITFB (4 mM) affords optimum inhibition efficiency of 78.86% from DEIS method. Addition of iodide ions to EMITFB has beneficial effect on the inhibition efficiency; 86.10% has been achieved by addition of 1 mM KI to 4 mM EMITFB. Adsorption of EMITFB molecules onto the metal surface is via physical adsorption mechanism and follows El Awady et al. kinetic/thermodynamic adsorption isotherm model. SEM and EDS results confirm the improvement of corrosion inhibiting ability of EMITFB by iodide ions. EMITFB and EMITFB + KI behave as mixed-type corrosion inhibitor in the studied environment.
Improved Uniform Sampling in Constrained Domains for Data-Driven Modelling of Antennas
- Sławomir Kozieł
- A Sigursson
2018
Data-driven surrogate modelling of antenna structures is an attractive way of accelerating the design process, in particular, parametric optimization. In practice, construction of surrogates is hindered by curse of dimensionality as well as wide ranges of geometry parameters that need to be covered in order to make the model useful. These difficulties can be alleviated by constrained performance-driven modelling with the surrogate domain spanned by a set of reference designs optimized with respect to selected figures of interest. Unfortunately, uniform training data allocation in such constrained domains is a nontrivial task. This paper proposes a new design of experiments technique which ensures sampling uniformity. Our approach is based on uniform sampling on the domain-spanning manifold and linear transformation of the remaining sample vector components onto orthogonal directions (w.r.t. the manifold). The proposed procedure is demonstrated using two antenna examples and shown to ensure considerable improvement of the surrogate model accuracy as compared to rudimentary random sampling. Application examples are also provided.
Improvement of opipramol base solubility by complexation with β-cyclodextrin
- Koleta Majewska
- Anna Skwierawska
- Beata Kamińska
- Marta Prześniak-Welenc
2018 Pełny tekst SUPRAMOLECULAR CHEMISTRY
Opipramol (OPI), a tricyclic antidepressant and anxiolytic compound, is administered orally in the form of a dihydrochloride. Salt form of the drug has a higher solubility in water and hence bioavailability and stability. A similar effect can be achieved by closing the hydrophobic part of the drug molecule in the cyclodextrin cavity. The paper presents opipramol inclusion complexes with beta-cyclodextrin (β-CD) in 1:1 molar ratio. Studies on the formation of inclusion complexes were carried out both in solution and in the solid state. The formation and physicochemical characterisation of the complexes were determined by UV spectroscopic measurement (UV–vis), Fourier Transform Infrared (FTIR) Spectroscopy, 1H Nuclear Magnetic Resonance (1H NMR, 2D NOESY NMR), thermoanalytical methods (TGA – Termogravimetric analysis, DSC – differential scanning calorimetry), X-ray diffractometry (XRD) and scanning electron microscopy (SEM). The phase solubility profile with β-CD was classified as the AN- type, indicating the formation of the inclusion complex with a drug.
Improvement of S355G10+N steel weldability in water environment by Temper Bead Welding
- Jacek Tomków
- Grzegorz Rogalski
- Dariusz Fydrych
- Jerzy Łabanowski
2018 JOURNAL OF MATERIALS PROCESSING TECHNOLOGY
The normalized S355G10 + N steel was chosen for testing, it is used in a variety of applications including the building of offshore structures, which may require repairs in water environment. The main aim of the work was to check susceptibility to cold cracking for fillet welds – Controlled Thermal Severity (CTS) tests and butt welds – Tekken tests and in the next step evaluation of effectiveness of Temper Bead Welding (TBW) application in wet welding conditions for joints welded by covered electrodes. The TBW effectiveness was experimentally verified as a method that may reduce the susceptibility to cold cracking in water environment. An application of the TBW technique caused the maximum hardness of the heat affected zone to fulfill the criterion of EN ISO 15614-1 standard in level of 380 HV10. It was determined that for S355G10 + N steel the beneficial range of the pitch value between beads is 75%–100%.