2021 - Repozytorium publikacji - Politechnika Gdańska

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Publikacje z roku 2021

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Ustawa a autonomia statutowa w Polsce i w Ukrainie: rozwiązania statutowe w sferze governance wybranych uczelni polskich i ukraińskich
- Krzysztof Leja
- Viacheslav Komarov
- Iryna Degtyarova
2021
Kierując się zasadą autonomii uczelni i deregulacji prawa oraz właściwym miejscem statutu w systemie źródeł prawa, w ramach tego rozdziału postanowili-śmy poddać analizie statuty wybranych uczelni w Polsce i w Ukrainie, na tle roz-wiązań ustawowych na podstawie następujących pytań badawczych:• W jaki sposób i w jakim stopniu uczelnie korzystają z uprawnień autonomicznych (w zakresie autonomii organizacyjnej) i potencjału Ustawy w swoich statutach? • Jakie sfery reguluje ustawa, a jakie statut? Czy i w jakim zakresie istnieje do-mniemanie właściwości statutów do regulowania spraw nieobjętych regulacją ustawową?• Czy statut przedstawia bardzo szczegółowe podejście, czy tylko ramy? Czy może statut odzwierciedlać sposób i charakter uczelnianej społeczności aka-demickiej (jako „polityczne” porozumienie wszystkich grup interesów?)
Uszkodzenia pożarowe dachu budynku kościoła pw. Świętych Apostołów Piotra i Pawła
- Tomasz Majewski
- Maciej Niedostatkiewicz
2021 Pełny tekst Przegląd Budowlany
W artykule przedstawionopsi działń podjętych po pożarze dachu zabytkowego Kcioła pw. Świętych Apostołów Piotra i Pawła w Gdańsku
Utilizing pulse dynamics for non-invasive Raman spectroscopy of blood analytes
- Maciej Wróbel
- Jeong Hee Kim
- Piyush Raj
- Ishan Barman
- Janusz Smulko
2021 Pełny tekst BIOSENSORS & BIOELECTRONICS
Non-invasive measurement methods offer great benefits in the field of medical diagnostics with molecular-specific techniques such as Raman spectroscopy which is increasingly being used for quantitative measurements of tissue biochemistry in vivo. However, some important challenges still remain for label-free optical spectroscopy to be incorporated into the clinical laboratory for routine testing. In particular, non-analyte-specific variations in tissue properties introduce significant variability of the spectra, thereby preventing reliable calibration. For measurements of blood analytes such as glucose, we propose to decrease the interference from individual tissue characteristics by exploiting the known dynamics of the blood-tissue matrix. We reason that by leveraging the natural blood pulse rhythm, the signals from the blood analytes can be enhanced while those from the static components can be effectively suppressed. Here, time-resolved measurements with subsequent pulse frequency estimation and phase-sensitive detection are proposed to recover the Raman spectra correlated with the dynamic changes at blood-pulse frequency. Pilot in vivo study results are presented to establish the benefits as well as outline the challenges of the proposed method in terms of instrumentation and signal processing.
Validation of Hydraulic Mechanism during Blowout Trauma of Human Orbit Depending on the Method of Load Application
- Marcin Zmuda Trzebiatowski
- Paweł Kłosowski
- Andrzej Skorek
- Krzysztof Żerdzicki
- Paweł Lemski
- Mateusz Koberda
2021 Pełny tekst Applied Bionics and Biomechanics
The more we know about mechanisms of the human orbital blowout type of trauma, the better we will be able to prevent them in the future. As long as the buckling mechanism’s veracity is not in doubt, the hydraulic mechanism is not based on equally strong premises. To investigate the correctness of the hydraulic mechanism’s theory, two different methods of implementation of the hydraulic load to the finite element method (FEM) model of the orbit were performed. The intraorbital hydraulic pressure was introduced as a face load applied directly to the orbit in the first variant, while in the second one the load was applied to the orbit indirectly as a set of nodal forces transferred from the external surface of the eyeball via the intraorbital tissues to the orbital walls within the contact problem. Such an approach is aimed at a better understanding of the pattern for the formation of blowout fractures during the indirect load applied to the orbital bones. The nonlinear dynamic analysis of both numerical models showed that the potential fracture was observed in the second variant only, embracing a relatively large area: both medial and lower wall of the orbit. Interestingly, the pressure generated by the intraorbital entities transferred the energy of the impact to the orbital sidewalls mainly; thus, the nature of the mechanism known as the hydraulic was far from the expected hydraulic pressure. According to the eyeball’s deformation as well as the areas of the greatest Huber-Mises-Hencky (H-M-H) stress within the orbit, a new term of strut mechanism was proposed instead of the hydraulic mechanism as more realistic regarding the investigated phenomenon. The results of the current research may strongly influence the development of modern implantology as well as affect forensic medicine.
Validation study on a new semi-empirical method for the prediction of added resistance in waves of arbitrary heading in analyzing ship speed trial results
- Jinbao Wang
- Sebastian Bielicki
- Florian Kluwe
- Hideo Orihara
- Gongzheng Xin
- Kenichi Kume
- Semyun Oh
- Shukui Liu
- Peiyuan Feng
2021 OCEAN ENGINEERING
This paper describes an open and extensive validation study carried out by the Specialist Committee on Ships in Operation at Sea (SOS) of the International Towing Tank Conference (ITTC) on the newly developed SHOPERA-NTUA-NTU-MARIC (SNNM) wave-added resistance prediction method. The SNNM method aims at a simple, fast and transparent determination of the added resistance in regular waves of arbitrary encounter directions, even when the hull geometry is not available. Prior to the validation study, a series of acceptance criteria for the new method were specified by the committee. Contributions of 1,477 added resistance experimental data samples from 8 institutions were collected, analyzed and cross-checked with satisfactory outcome, which finally led to the inclusion of the new method into the ITTC recommended sea trial procedure as an important progress. Some aspects of concerns are discussed in detail and further work in the future is recommended.
Valorization of waste cabbage leaves by postharvest photochemical treatments monitored with a non-destructive fluorescence-based sensor
- Artur Kowalski
- Giovanni Agati
- Maria Grzegorzewska
- Ryszard Kosson
- Barbara Kusznierewicz
- Tomasz Chmiel
- Agnieszka Bartoszek-Pączkowska
- Lorenza Tuccio
- Daniele Grifoni
- Ingunn M. Vagen
- Stanislaw Kaniszewski
2021 Pełny tekst JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY
The biosynthesis of polyphenolic compounds in cabbage waste, outer green leaves of white head cabbage (Brassica oleracea L. var. capitata subvar. alba), was stimulated by postharvest irradiation with UVB lamps or sunlight. Both treatments boosted the content of kaempferol and quercetin glycosides, especially in the basal leaf zone, as determined by the HPLC analysis of leaf extracts and by a non-destructive optical sensor. The destructive analysis of samples irradiated by the sun for 6 days at the end of October 2015 in Skierniewice (Poland) showed an increase of leaf flavonols by 82% with respect to controls. The treatment by a broadband UVB fluorescent lamp, with irradiance of 0.38 W m−2 in the 290–315 nm range (and 0.59 W m−2 in the UVA region) for 12 h per day at 17 °C along with a white light of about 20 μmol m−2 s−1, produced a flavonols increase of 58% with respect to controls. The kinetics of flavonols accumulation in response to the photochemical treatments was monitored with the FLAV non-destructive index. The initial FLAV rate under the sun was proportional to the daily radiation doses with a better correlation for the sun global irradiance (R2 = 0.973), followed by the UVA (R2 = 0.965) and UVB (R2 = 0.899) irradiance. The sunlight turned out to be more efficient than the UVB lamp in increasing the flavonols level of waste leaves, because of a significant role played by UVA and visible solar radiation in the regulation of the flavonoid accumulation in cabbage. The FLAV index increase induced on the adaxial leaf side was accompanied by a lower but still significant FLAV increase on the unirradiated abaxial side, likely due to a systemic signaling by mean of the long-distance movement of macromolecules. Our present investigation provides useful data for the optimization of postharvest photochemical protocols of cabbage waste valorization. It can represent a novel and alternative tool of vegetable waste management for the recovery of beneficial phytochemicals.
Vibro piles performance prediction using result of CPT
- Paweł Więcławski
2021 Pełny tekst Studia Geotechnica et Mechanica
Vibro piles belong to the group of full displacement piles with an expanded base, characterised by a very high load capacity, especially in non-cohesive soils. The problem is to adopt a reliable method for the determination of full load–settlement (Q–s) curve. A frequent difficulty is the determination of the load capacity limit based on the static load test because the course of the load–settlement curve is of a linear nature. This publication presents the empirical method. It allows direct prediction of a full axially loaded pile settlement curve based on the values of qc cone resistance obtained in cone penetration test (CPT). The advantage offered by this procedure is the accuracy of the obtained limit values in relation to the actual load-bearing capacity as compared to other methods based on soil parameters obtained in in situ testing. An additional advantage is the Q–s characteristics, which enable designing for intermediate values, allowing for the criterion of minimal or equal settlements. The shape of analytical curves was compared with static pile load test (SPLT) curves. This comparison showed large convergences between the analytical and measured curves.
Virulence of Clinical Candida Isolates
- Martyna Mroczyńska
- Anna Brillowska-Dąbrowska
2021 Pełny tekst Pathogens
The factors enablingCandidaspp. infections are secretion of hydrolytic enzymes, adher-ence to surfaces, biofilm formation or morphological transition, and fitness attributes. The aim of thisstudy was to investigate the correlation between known extracellular virulence factors and survivalofGalleria mellonellalarvae infected with clinicalCandida. The 25 isolates were tested and the activityof proteinases among 24/24, phospholipases among 7/22, esterases among 14/23, hemolysins among18/24, and biofilm formation ability among 18/25 isolates was confirmed. Pathogenicity investiga-tion usingG. mellonellalarvae as host model demonstrated thatC. albicansisolates andC. glabrataisolate were the most virulent andC. kruseiisolates were avirulent.C. parapsilosisvirulence wasidentified as varied,C. inconspicuawere moderately virulent, and oneC. palmioleophilaisolate was oflow virulence and the remaining isolates of this species were moderately virulent. According to ourstudy, virulence ofCandidaisolates is related to the expression of proteases, hemolysins, and esterases.
Visegrád countries' scientific productivity in the European context: a 10-year perspective using Web of Science and Scopus
- Magdalena Szuflita-Żurawska
- Beata Basińska
2021 Pełny tekst LEARNED PUBLISHING
Measuring the growth of research productivity is a core element of performance in the higher education sector. This paper aims to analyse the scientific productivity of the Visegrád Group countries (2010-2019) based on data from the WoS and Scopus databases as well as data from secondary sources (demographic and socio-economic factors). Quantitatively, although Poland has the highest output, this is due to its comparative size, whereas output per researcher in Poland is lower than in other V4 countries. As regards the qualitative approach, Hungary and the Czech Republic are significantly more effective in terms of scientific collaboration and receive a greater number of European Research Council grants. Thus, bibliometric data in relation to cross-country characteristic indicators (socio-economic variables including expenditure on science and having prestigious universities) are related to the positions of the V4 countries. Practical implications suggest that university management within the Visegrád Group must develop and continue strategies to strengthen international collaboration between researchers in order to accelerate change in the dissemination of scientific output at the global level. Academic scholarly publishers may benefit from publishing research on specific issues important to different regions of the world in order to expand their audience and gain new potential resources.
Visible-light-driven lanthanide-organic-frameworks modified TiO2 photocatalysts utilizing up-conversion effect
- Patrycja Parnicka
- Wojciech Lisowski
- Tomasz Klimczuk
- Justyna Łuczak
- Andrzej Żak
- Adriana Zaleska-Medynska
2021 Pełny tekst APPLIED CATALYSIS B-ENVIRONMENTAL
Highly efficient and quite stable composite with core-shell-like architecture reported herein, responds to the challenge of sunlight-driven photocatalysts. The Ln(ndc)/TiO2 photocatalytic system comprises active lanthanide-carboxylate coordination networks (Nd, Er, Ho, and Tm as metal ions, and 2,6-naphthalene dicar-boxylic acid as the organic linker) and inert titanium dioxide and allow to convert incompatible visible radiation into functional ultraviolet photons. The combination of the antenna-reactor photocatalyst complex with Ln(ndc) shell layers promotes light harvesting and efficient mass transfer, resulting in additional photoexcited electrons. The Nd(ndc) metal-organic framework successfully activate TiO2 via up-conversion energy transfer. The apparent quantum efficiency, determined at wavelengths corresponding to the transitions from the Nd3+ground state, equals to 2.8% and 3.2% for 525 and 583 nm, respectively. Integration of the Nd(ndc) MOF and TiO2 results in the highest efficiency of phenol degradation, affording a value of 87.5% after 60 min of visible light (λ >420 nm) exposure.
Voice Multilateration System
- Robert Burczyk
- Krzysztof Cwalina
- Małgorzata Gajewska
- Jarosław Magiera
- Piotr Rajchowski
- Jarosław Sadowski
- Jacek Stefański
2021 Pełny tekst SENSORS
This paper presents an innovative method of locating airplanes, which uses only voice communication between an air traffic controller and the pilot of an aircraft. The proposed method is described in detail along with its practical implementation in the form of a technology demonstrator (proof of concept), included in the voice communication system (VCS). A complete analysis of the performance of the developed method is presented, including the results of simulation and measurement tests in real conditions. The obtained results are very optimistic and indicate that the proposed solution may constitute an alternative method of locating aircraft in emergency conditions, i.e., a backup solution in the case of failure of other positioning systems.
Voltage variations and their reduction in a rural low-voltage network with PV sources of energy
- Agata Szultka
- Seweryn Szultka
- Stanisław Czapp
- Ryszard Zajczyk
2021 Pełny tekst Electronics
Renewable sources of energy (RES), especially photovoltaic (PV) micro-sources, are very popular in many countries. This way of clean power production is applied on a wide scale in Poland as well. The Polish legal regulations and tariffs specify that every prosumer in a low-voltage network may feed this network with a power not higher than the maximum declared consumed power. In power networks with RES, the voltage level changes significantly along the power line and depends on the actually generated as well as consumed power by particular prosumers. There are cases that prosumers connected to this line cannot produce and inject the full permissible power from PV sources due to the level of a voltage higher than the technically acceptable value. In consequence, it leads to the lack of profitability of investments in installations with PV sources. In this paper, voltage variations in a real rural low-voltage network with PV micro-sources are described. The possible two general solutions of voltage levels improvement are discussed – increase in the cross-sectional area of the bare conductors in the existing overhead line as well as the replacement of the overhead line with a cable line. The recommended solution for the analyzed network, giving the best reduction of voltage variations and acceptable cost, is underlined. Such a recommendation can also be utilized in other rural networks.
Volumetric and torque efficiency of pumps during start-up in low ambient temperatures
- Ryszard Jasiński
2021
The volumetric, torque and total efficiency of hydraulic pumps change during start-up in low ambient temperatures, as well as in thermal shock conditions, un-til they reach the set conditions. The time to reach steady-state conditions de-pends on many parameters: ambient temperature, flow rate, fluid temperature, design of hydraulic units. The author carried out tests of hydraulic pumps in the Hydraulics Laboratory of the Faculty of Mechanical Engineering of the Gdańsk University of Technology. In the research four types of pumps were investigated: several gear pumps, two axial piston pumps of different designs and one radial piston pump. It was proved, that in thermal shock conditions some malfunctions may occur, espe-cially with large temperature difference between oil and pump. Experimental research of various hydraulic pumps operating in low ambient temperatures, undertaken by the author, allows to answer the question how the volumetric and torque efficiency changes in such conditions and what parame-ters does it depend on.
Warstwa odcinająca z geotekstyliów w nawierzchniach drogowych. Wymagania i zasady doboru właściwości
- Jacek Alenowicz
2021 Pełny tekst Magazyn Autostrady
W artykule omówiono zagadnienia związane ze stosowaniem geotekstyliów jako warstwy odcinającej w budowie nawierzchni drogowych. Podano wymagania ogólne, jakie stawia się geotekstylion w omawianym zastosowaniu. Przedstawiono klasyfikacje wykorzystywane w wybranych krajach oraz wymagania stosowane w Polsce. Zwrócono uwagę na czynniki wpływające na prawidłowy wybór geotekstyliów do wykonania warstwy odcinającej
Waste materials assessment for phosphorus adsorption toward sustainable application in circular economy
- Magda Kasprzyk
- Krzysztof Czerwionka
- Magdalena Gajewska
2021 Pełny tekst RESOURCES CONSERVATION AND RECYCLING
Phosphorus is the main determinant of nutrient enrichment in the water bodies. Many resources including nutrients may be shortly exhausted, assuming current consumption. This scenario leads to growing interest in resources recovery and/or reuse, which together with sustainable energy consumption and waste reduction are the main courses of the circular economy. Usage of coagulants in wastewater treatment plants (WWTP) does not allow phosphorus to be recovered from the sludge. An alternative method with recovery potential is the application of adsorbents. Many adsorbents have been approved for P-removal, however some of them are expensive. Response to that issue may be the application of waste materials and byproducts often intended for disposal/utilization. The main objective was to assess the P-removal efficiency of the waste materials/byproducts for application in small WWTP and eco-technologies like treatment wetlands as replacement of commercial adsorbents and alternative for conventional (chemical) treatment for potential phosphorus recovery. The materials investigated were (1) an expensive man-made product, (2) a byproduct with a high content of calcium oxide, and (3) drinking water treatment residuals (DWTRs) as beds from filters used to remove iron. Research was conducted in non-flow condition with various initial concentrations. The highest efficiency was received for fine-grained byproduct (9.58 mg/g), for commercial adsorbent LMB - 9.11 mg/g. The DWTRs adsorption was oscillated around 4.5 mg/g. These results confirmed the possibility of applying waste materials and byproducts for P-removal according to the circular economy idea. Further research should include implications of waste materials application to determine P-recovery concept.
Wastes from Agricultural Silage Film Recycling Line as a Potential Polymer Materials
- Jerzy Korol
- Aleksander Hejna
- Klaudiusz Wypiór
- Krzysztof Mijalski
- Ewelina Chmielnicka
2021 Pełny tekst Polymers
The recycling of plastics is currently one of the most significant industrial challenges. Due to the enormous amounts of plastic wastes generated by various industry branches, it is essential to look for potential methods for their utilization. In the presented work, we investigated the recycling potential of wastes originated from the agricultural films recycling line. Their structure and properties were analyzed, and they were modified with 2.5 wt % of commercially available compatibilizers. The mechanical and thermal performance of modified wastes were evaluated by tensile tests, thermogravimetric analysis, and differential scanning calorimetry. It was found that incorporation of such a small amount of modifiers may overcome the drawbacks caused by the presence of impurities. The incorporation of maleic anhydride-grafted compounds enhanced the tensile strength of wastes by 13–25%. The use of more ductile compatibilizers—ethylene-vinyl acetate and paraffin increased the elongation at break by 55–64%. The presence of compatibilizers also reduced the stiffness of materials resulting from the presence of solid particles. It was particularly emphasized for styrene-ethylene-butadiene-styrene and ethylene-vinyl acetate copolymers, which caused up to a 20% drop of Young’s modulus. Such effects may facilitate the further applications of analyzed wastes, e.g., in polymer film production. Thermal performance was only slightly affected by compatibilization. It caused a slight reduction in polyethylene melting temperatures (up to 2.8 °C) and crystallinity degree (up to 16%). For more contaminated materials, the addition of compatibilizers caused a minor reduction in the decomposition onset (up to 6 °C). At the same time, for the waste after three washing cycles, thermal stability was improved. Moreover, depending on the desired properties and application, materials do not have to go through the whole recycling line, simplifying the process, reducing energy and water consumption. The presented results indicate that it is possible to efficiently use the materials, which do not have to undergo the whole recycling process. Despite the presence of impurities, they could be applied in the manufacturing of products which do not require exceptional mechanical performance.
Water Behavior Near the Lipid Bilayer
- Natalia Kruszewska
- Krzysztof Domino
- Piotr Weber
2021
In this chapter, we focus on the dynamics of water molecules situated in the vicinity of a phospholipid bilayer. Using a molecular dynamics simulation method, we studied interactions between water and the bilayer and tracked trajectories of the water molecules. Based on the hypothesis that molecules trapped inside the bilayer make different motions than the ones which are either attached to the surface or move freely in the water bulk, we divided the water molecules into three groups – the ones that exhibited subdiffusion (confined) motion, the ones that move diffusionally in the bulk and the ones that move superdiffusively due to interactions with the moving bilayer. In detail, the water behavior near the bilayer has been analyzed by mean squared displacement and entropy computed separately for the above mentioned three groups of molecules. To explain the subdiffusion motion of the water molecules, the number and the duration of hydrogen bonds created between water molecules and the bilayer have been investigated. In addition, we examined the mechanism of water molecule self-diffusion, by means of statistical tests. Our studies aim to present insight into the understanding of the lipid’s role in water self-diffusion, which can be responsible for triggering different tribological responses of the system.
Water-lubricated stern tube bearing - experimental and theoretical investigations of thermal effects
- Michał Wodtke
- Wojciech Litwin
2021 Pełny tekst TRIBOLOGY INTERNATIONAL
The paper presents research results of thermal phenomena accompanying operation of a water-lubricated stern tube bearing with axial grooves. Experimental tests revealed, that intensity of forced axial flow has strong influence on bush temperature. Numerical simulations focused on investigation of the thermal phenomena under operation of water-lubricated journal bearing showed, that restricted axial flow promotes backflow of the water from bearing’s side zones through the grooves. The backflow temperature is higher than the supply temperature since under the conditions of restricted forced axial flow, it is impacted mainly by the temperature of the water outflow from the gap, which is higher due to the shearing of lubricating film. This effect causes rise in the temperature of the bearing bush.
W-dominance: Tradeoff-inspired dominance relation for preference-based evolutionary multi-objective optimization
- Rafał Szłapczyński
- Joanna Szłapczyńska
2021 Pełny tekst Swarm and Evolutionary Computation
The paper presents a method of incorporating decision maker preferences into multi-objective meta-heuristics. It is based on tradeoffcoefficients and extends their applicability from bi-objective to multi-objective. The method assumes that a decision maker specifies a priori each objective’s importance as a weight interval. Based on this, w-dominance relation is introduced, which extends Pareto dominance. By replacing reference points with weight intervals the method eliminates the need for any knowledge concerning expected solutions. Instead, decision maker reflects his context-independent policy regarding objectives. The proposed w-dominance was incorpo- rated into selected multi-objective metaheuristics. Following this, three new metrics were designed. The metrics include prescreening true Pareto Front and final population according to w-dominance relation. Based on pre- liminary tests, Vector Angle Evolutionary Algorithm (VaEA) was selected as the best match for w-dominance. W-dominance-extended VAEA (wVAEA) was compared in a series of simulations with four state-of-the-art refer- ence point-based multi-objective algorithms. The results show that wVaEA outperforms the four representative algorithms for selected benchmark problems.
Weakly-Supervised Word-Level Pronunciation Error Detection in Non-Native English Speech
- Daniel Korzekwa
- Jaime Lorenzo-trueba
- Thomas Drugman
- Shira Calamaro
- Bożena Kostek
2021 Pełny tekst
We propose a weakly-supervised model for word-level mispronunciation detection in non-native (L2) English speech. To train this model, phonetically transcribed L2 speech is not required and we only need to mark mispronounced words. The lack of phonetic transcriptions for L2 speech means that the model has to learn only from a weak signal of word-level mispronunciations. Because of that and due to the limited amount of mispronounced L2 speech, the model is more likely to overfit. To limit this risk, we train it in a multi-task setup. In the first task, we estimate the probabilities of word-level mispronunciation. For the second task, we use a phoneme recognizer trained on phonetically transcribed L1 speech that is easily accessible and can be automatically annotated. Compared to state-of-the-art approaches, we improve the accuracy of detecting word-level pronunciation errors in AUC metric by 30% on the GUT Isle Corpus of L2 Polish speakers, and by 21.5% on the Isle Corpus of L2 German and Italian speakers