2021 - Repozytorium publikacji - Politechnika Gdańska

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Ice Load Characteristics on Floating Photovoltaic Platform
- Tomasz Kolerski
- Dariusz Gąsiorowski
- Parisa Radan
2021 Pełny tekst ENERGIES
Nowadays, based upon human needs and preferring perpetual types of energy, photovoltaic system (PV) is a suitable alternative and more frequently used in northern countries, which are recently more attracted by solar power. The new floating type of the structure is installed in the water bodies instead of land. One of the main elements in floating photovoltaic structures is the forces imposed on the panels. In the northern regions, the dominant load is considered to be ice interaction with the structure. This study aims at identifying the loads imposed on a floating PV structure located in the Łapino Reservoir on the Radunia River, which are produced by the wind action on the ice cover. The wind velocity varying between 10 and 26 m/s is implemented, and also the reduction of the pool level was studied. Wind direction plays an important role in the inclination and expansion of ice accumulation. Moreover, the magnitude of wind velocity is a determinative factor in the maximum thickness emerged in various spot of the area. Changes in pool level reduction is not able to cause noticeable changes in ice cover expansion and maximum ice thickness. Additionally, the shoving mechanism is able to originate abrupt changes in ice thickness by means of rising wind velocity
ICT, financial markets and their impact on firms’ performance and internationalisation
- Joanna Wolszczak-Derlacz
2021
The effects of information and communication technology (ICT) and financial development on growth are highly debated in the literature. Motivated by previous studies and their mixed results, in this study, we propose an analysis to re-examine the ICT-finance puzzle. We go beyond country-specific or sector-specific studies and conduct cross-country analysis with firm-level data. It enables obtaining a broad picture of the ICT-finance-growth nexus. Importantly, our analysis takes into account enterprises from emerging and transformation economies. This study aims threefold. First, we want to answer the question whether the usage of ICT and easier access to financial resources (lower finance constraints) are among the crucial determinants of firms’ performance (labour productivity). The second aim is to examine what the main determinants of firms’ involvement in internationalisation processes are and to what extent the usage of ICT and access to financial resources determine a company’s decision to enter foreign markets. This part of the analysis is rooted in Melitz (2003) model where firms’ heterogeneity is taken into account. Finally, we look more closely at the performance of enterprises during coronavirus disease of 2019 (COVID-19).
Identification of Fast Time-varying Communication Channels Using the Preestimation Technique
- Maciej Niedźwiecki
- Artur Gańcza
- Piotr Kaczmarek
2021 Pełny tekst IFAC-PapersOnLine
Accurate identification of stochastic systems with fast-varying parameters is a challenging task which cannot be accomplished using model-free estimation methods, such as weighted least squares, which assume only that system coefficients can be regarded as locally constant. The current state-of-the-art solutions are based on the assumption that system parameters can be locally approximated by a linear combination of appropriately chosen basis functions. The paper shows that tracking performance of the resulting local basis function estimation algorithms can be further improved by means of regularization. The method is illustrated by an important recent application - identification of fast time-varying acoustic channels used in underwater communication.
Identification of novel halogenated naturally occurring compounds in marine biota by high-resolution mass spectrometry and combined screening approaches
- Lidia Belova
- Yukiko Fujii
- Paulien Cleys
- Monika Śmiełowska
- Koichi Haraguchi
- Adrian Covaci
2021 Pełny tekst ENVIRONMENTAL POLLUTION
Marine animals, plants or bacteria are a source of bioactive naturally-occurring halogenated compounds (NHCs) such as bromophenols (BPs), bromoanisoles (BAs) and hydroxylated or methoxylated analogues of polybrominated diphenyl ethers (HO-PBDEs, MeO-PBDEs) and bromobiphenyls (HO-BBs, MeO-BBs). This study applied a comprehensive screening approach using liquid chromatography high-resolution mass spectrometry and combining target, suspect and non-target screening with the aim to identify new hydroxylated NHCs which might be missed by commonly applied gas chromatographic methods. 24 alga samples, 4 sea sponge samples and 7 samples of other invertebrates were screened. Target screening was based on 19 available reference standards of BPs, (di)OH-BDEs and diOH-BBs and yielded seven unequivocally identified compounds. 6OH-BDE47 was the most frequently detected compound with a detection frequency of 31%. Suspect screening yielded two additional compounds identified in alga samples as well as 17 and 8 compounds identified in sea sponge samples of Lamellodysidea sp. and Callyspongia sp., respectively. The suspect screening results presented here confirmed the findings of previous studies conducted on sea sponge samples of Lamellodysidea sp. and Callyspongia sp. Additionally, in Lamellodysidea sp. and Callyspongia sp. 13 and 4 newly identified NHCs are reported including heptabrominated diOH-BDE, monochlorinated pentabrominated diOH-BDE, hexabrominated OH–MeO-BDE and others. Non-target screening allowed the identification of 31 and 20 polyhalogenated compounds in Lamellodysidea sp. and Callyspongia sp. samples, respectively. Based on the obtained fragmentation spectra, polybrominated dihydroxylated diphenoxybenzenes (diOH-PBDPBs), such as hepta-, octa- and nonabrominated diOH-BDPBs, could be identified in both species. To our knowledge, this study is the first report on the environmental presence of OH-PBDPBs.
Identification of residual force in static load tests on instrumented screw displacement piles
- Adam Krasiński
- Mateusz Wiszniewski
2021 Pełny tekst Studia Geotechnica et Mechanica
Occurrence of the so-called residual force of an unknown value significantly disturbs interpretation of static load tests performed on piles equipped with additional measuring instruments. Screw displacement piles are the piling technology in which the residual force phenomenon is very common. Its formation mechanism is closely related to the installation method of this type of piles, which initiates generation of negative pile skin friction without any additional external factors. Knowledge of the value and distribution of a residual force (trapped in a pile shaft before starting the load test) is a condition necessary for the proper interpretation of instrumented pile test results. In this article, a clear and easy-to-use method of residual force identification, based on the analysis of shaft deformations recorded during pile unloading is presented. The method was successfully verified on two pile examples and proved to be effective and practical.
Identification of synergistic and antagonistic actions of environmental pollutants: Bisphenols A, S and F in the presence of DEP, DBP, BADGE and BADGE·2HCl in three component mixtures
- Natalia Jatkowska
- Błażej Kudłak
- Patrycja Lewandowska
- Wen Liu
- Michael Williams
- Helgi B. Schiöth
2021 SCIENCE OF THE TOTAL ENVIRONMENT
Ecosystems are facing increased pressure due to the emission of many classes of emerging contaminants. However, very little is known about the interactions of these pollutants, such as bisphenols (BPs), plasticizers or pharmaceuticals. By employing bioluminescent bacteria (Microtox assay), we were able to define interactions between selected emerging pollutants (namely BPA, BPS, BPF, BADGE, BADGE·2HCl, DEP, DBP) in ternary mixtures, at environmentally relevant concentration levels (down to as low as 1.89, 1.42, 3.08, and 0.326 μM for, respectively, BPA, BPF, BPS and BADGE·2HCl).Weprovide the first systematic analysis of bisphenols and phthalates in three component mixtures. Using this system, we performed toxicity modelling with concentration addition (CA) and independent action (IA) approaches, followed by data interpretation using Model Deviation Ratio (MDR) evaluation. Interestingly, we mathematically and experimentally confirmed a novel synergy between BPA, BADGE and BADGE·2HCl. The synergy of BPA, BADGE and BADGE·2HCl is distinct, with both models suggesting these analytes have a similar mode of action (MOA).
Identifying and Mitigating the Negative Effects of Power in Organizations
- Paweł Ziemiański
2021 Pełny tekst Journal of Applied Social Science
This article investigates the possible negative effects of power in organizations. It demonstrates how holding power may affect an individual’s perception of others, actions, and cognition. Ways in which power may have a detrimental effect on different aspects of a manager’s functioning within an organization, including building relationships, communication, and performance are analyzed. It is argued that individuals are unaware of these effects, and thus it is necessary to introduce methods of their diagnosis and countermeasures on the organizational level. In addition, negative phenomena associated with the power’s distribution among organizations’ units and its structural aspects are analyzed. A set of questions is proposed, which can be used by individuals and organizations to reveal the extent to which adverse effects of power are present in an organization. These inquiries can be used to design and introduce specific countermeasures and improve communications and the quality of interactions within organizations. Selected countermeasures are also proposed in the article.
IFE: NN-aided Instantaneous Pitch Estimation
- Marek Blok
- Jan Banaś
- Mariusz Pietrołaj
2021 Pełny tekst
Pitch estimation is still an open issue in contemporary signal processing research. Nowadays, growing momentum of machine learning techniques application in the data-driven society allows for tackling this problem from a new perspective. This work leverages such an opportunity to propose a refined Instantaneous Frequency and power based pitch Estimator method called IFE. It incorporates deep neural network based pitch estimation with audio front end used for extraction of instantaneous frequency and power of signal components. A thorough results analysis is performed and major advantages and shortcomings of this method are identified, leading to a wide array of suggestions for future improvement While IFE exhibits an instantaneous temporal resolution, a comparison is made against state-of-the-art pitch estimators operating on time windows, proving a comparable degree of prediction accuracy (up to 6% accuracy improvement) while maintaining the advantage of higher temporal resolution.
Image-based numerical modeling of the tensile deformation behavior and mechanical properties of additive manufactured Ti–6Al–4V diamond lattice structures
- M. Doroszko
- A. Falkowska
- Andrzej Seweryn
2021 Pełny tekst MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING
This work concerns the numerical modeling of the deformation process and mechanical properties of structures obtained by the additive method laser power bed fusion (LPBF). The investigation uses diamond structures of Ti–6Al–4V titanium implantation alloy with various relative densities. To model the process of tensile deformation of the materials, geometric models were used, mapping the realistic shape of the examined structures. To recreate the geometry of the samples, computed tomography (CT) and microtomography (micro-CT) were used, which allowed to obtain two accuracy levels of the mapping details of the investigated structures shape. Taking into account the nonlinearity of the material in the computational model makes it possible to model the deformation process of cellular materials until the fracture initiation. On the basis of the performed calculations using the finite element method (FEM), the stress and strain distributions in deformed structures were obtained and analyzed. The relationship between the shape of cellular structures and their effective mechanical properties on a macroscopic scale was investigated. The influence of the accuracy of the structures shape mapping on their strength properties and stress and strain distributions was also described. On the basis of the conducted research, fracture initiation localizations in titanium cellular structures were indicated. Finally, the results of the numerical calculations were verified by experimental tests.
Imaging of Increasing Damage in Steel Plates Using Lamb Waves and Ultrasound Computed Tomography
- Monika Zielińska
- Magdalena Rucka
2021 Pełny tekst Materials
This paper concerns inspection of steel plates, with particular emphasis on the assessment of in-creasing damage. Non-destructive tests were performed on four plates, one of which was un-damaged, while the remaining three had a defects in the form of circular holes with a diameter of 2, 5, and 10 cm. Guided Lamb waves were used in the research, and the image reconstruction was performed using ultrasound computed tomography. The damage size was estimated by tracking the real course of rays and densifying the pixel grid into which the object was divided. The re-sults showed the great potential of ultrasound tomography in detecting defects in steel elements, together with the possibility of estimating damage size.
Immersive Technologies that Aid Additive Manufacturing Processes in CBRN Defence Industry
- Małgorzata Gawlik-Kobylińska
- Paweł Maciejewski
- Jacek Lebiedź
- Alexander Kravcov
2021 International Journal on Information Technologies and Security
Testing unique devices or their counterparts for CBRN (C-chemical, B-biological, R-radiological, N-nuclear) defense relies on additive manufacturing processes. Immersive technologies aid additive manufacturing. Their use not only helps understand the manufacturing processes, but also improves the design and quality of the products. This article aims to propose an approach to testing CBRN reconnaissance hand-held products developed by additive manufacturing. According to the approach, tactical training with the use of the 3D object or their printed versions can be helpful in military products development by providing data on user experience. Training for testing can enhance their quality regarding intuitiveness and easiness in use. It can be concluded that the fast-evolving technological landscape requires novel approaches in developing and testing military products.
IMMIGRANTY IZ STRAN BYVSHEGO SSSR I POL'SKIY GOSUDARSTVENNYY INTERES
- Krystyna Gomółka
2021
Пребывание иммигрантов из государств бывшего СССР в Польше регулируется положениями международного, европейского и национального права. Соотношение между въехавшими в Польшу на постоянное место жительства и выехавшими из нее в 2004- 2015 гг. было отрицательным, только в 2016 г. в Польшу прибыло больше мигрантов, чем уехало из нее. В 2004 г. иммигранты из государств бывшего СССР составляли 61% общего количества иммигрантов, въехавших в Польшу для проживания на постоянной основе, тогда как в 2016 г. – 54,6%. Наиболее многочисленная группа иммигрантов прибывала в страну на определенное время для работы или учебы. Вплоть до 2017 г. больше половины граждан стран бывшего СССР устраивались на работу нелегально. Однако ситуация изменилась после принятия 20 июля 2017 г. поправок в Закон о содействии занятости и организациях рынка труда. Иностранцы, приезжающие из Армении, Белоруссии, Грузии, Молдавии, России и Украины, могут воспользоваться упрощенной процедурой доступа к рынку труда для устройства на работу на краткосрочный период. Согласно поправкам в закон, наряду с разрешениями на работу, которые выдает воевода на срок до трех лет, было введено разрешение на сезонную работу, выдаваемое старостой на срок до девяти месяцев в течение календарного года. В этот период у работодателей существенно возросла потребность в рабочей силе с востока, особенно в работниках с Украины. Рост числа иностранцев на польском рынке труда – это также вызов полякам, возвращающимся на родину из Великобритании. Сложно однозначно определить, сколько поляков вернется насовсем и найдут ли они работу, соответствующую их знаниям и полученному опыту, а также в какой степени они будут вынуждены конкурировать с иммигрантами из государств бывшего СССР
Impact of AI-Based Tools and Urban Big Data Analytics on the Design and Planning of Cities
- Dorota Kamrowska-Załuska
2021 Pełny tekst Land
Wide access to large volumes of urban big data and artificial intelligence (AI)-based tools allow performing new analyses that were previously impossible due to the lack of data or their high aggregation. This paper aims to assess the possibilities of the use of urban big data analytics based on AI-related tools to support the design and planning of cities. To this end, the author introduces a conceptual framework to assess the influence of the emergence of these tools on the design and planning of the cities in the context of urban change. In this paper, the implications of the application of artificial-intelligence-based tools and geo-localised big data, both in solving specific research problems in the field of urban planning and design as well as on planning practice, are discussed. The paper is concluded with both cognitive conclusions and recommendations for planning practice. It is directed towards urban planners interested in the emerging urban big data analytics based on AI-related tools and towards urban theorists working on new methods of describing urban change
Impact of digital technologies on reliability of risk forecasting models - case study of enterprises in three global financial market regions
- Tomasz Korol
2021
This chapter focuses on the evaluation of impact of ICT on reliability of financial risk forecasting models. Presented study shows how the development of ICT can improve the effectiveness of such models. Determining a firm’s financial risk is one of the most interesting topics for investors and decision-makers. The multifaceted goal of the presented research is to separately estimate five traditional statistical and five soft computing models for enterprises in Far-East Asia, Europe and Latin America (together with offering 30 different forecasting models) and to identify the most effective method for predicting the financial failure of enterprises in the short-, medium- and long-term for firms in each region. A further goal is to evaluate which method is characterized by the smallest decrease of effectiveness in increasing the forecast horizon. Thus it will allow to compare the behavior of traditional and the latest IT techniques. This study is one of the first attempts in the literature to estimate a bankruptcy forecasting model using such a wide range of methods and focusing on enterprises in three different financial markets.
Impact of dyes isomerization effect on the charge transfer phenomenon occurring on the dye/nanosemiconductor interface
- Oleksandr Korolevych
- Maciej Zalas
- Waldemar Stampor
- Abdel Hadi Kassiba
- Małgorzata Makowska-janusik
2021 SOLAR ENERGY MATERIALS AND SOLAR CELLS
The present work aimed to find the answer how does the isomerization of the Ru based dyes affect the overall photon-to-current efficiency of the DSSCs and to explain the charge transfer phenomenon occurring on the dye/ nanosemiconductor interface. Therefore, electronic and optical properties of three bipyridine derivatives anchored on the TiO2 electrode were investigated by computational simulations based on quantum chemistry codes performed on a cluster model and the predictions compared with experimental responses. The quantum chemical calculations carried out for the para-, meta- and ortho-isomers has given the possibility to explain the role of an anchor group position in the DSSC devices design. An in-depth analysis of the obtained data shows that the nature of the bonding between the anchor groups and the semiconducting nanoparticles affects the charge transfer at the interfaces. The electronic properties obtained for the hybrid systems and their components indicate that solar cells with the para-derivatives of the Ru based dyes as sensitizers exhibit the highest photo conversion efficiency. The observed phenomenon was explained based on the photogenerated excitons in the organic groups and their dissociation at the dye/semiconductor interfaces to ensure the free charge carriers
Impact of Geometrical Imperfections on Estimation of Buckling and Limit Loads in a Silo Segment Using the Vibration Correlation Technique
- Łukasz Żmuda-Trzebiatowski
- Piotr Iwicki
2021 Pełny tekst Materials
The paper examines effectiveness of the vibration correlation technique which allows determining the buckling or limit loads by means of measured natural frequencies of structures. A steel silo segment with a corrugated wall, stiffened with cold-formed channel section columns was analysed. The investigations included numerical analyses of: linear buckling, dynamic eigenvalue and geometrically static non-linear problems. Both perfect and imperfect geometries were considered. Initial geometrical imperfections included first and second buckling and vibration mode shapes with three amplitudes. The vibration correlation technique proved to be useful in estimating limit or buckling loads. It was very efficient in the case of small and medium imperfection magnitudes. The significant deviations between the predicted and calculated buckling and limit loads occurred when large imperfections were considered.
Impact of the Alkyl Side Chains of Cations and Anions on the Activity and Renaturation of Lysozyme: A Systematic Study Performed Using Six Amino‐Acid‐Based Ionic Liquids
- Paulina Rakowska
- Adam Kloskowski
2021 ChemistrySelect
The impact of the structure of ionic liquid on the activity and renaturation of lysozyme from the hen egg white (HEWL) was investigated. A set of six ionic liquids based on morpholinium cation and N-acylated amino acids as anions were exploited. The matrix used was based on two homologous series: one with N-acetyl-L-valinate [Val] as a common anion and morpholinium cation with a different number of carbon atoms in the n-alkyl chain (n=2, 4, 6, 8); and second, a common N-butyl-N-methylmorpholinium cation and different N-acylated amino acids. Interactions of ionic liquids with HEWL were explored by analyzing the changes in the activity of the enzyme based on the rate of hydrolysis of a β-1,4-glycosidic bond between components of peptidoglycan in the cell wall of Micrococcus luteus bacteria. The results demonstrated various mechanisms of interaction of cations and anions with HEWL, and hence, different trends in the association between the number of carbon atoms and the given property.
Impact response of novel layered two stage fibrous composite slabs with different support type
- R. Rithanyaa
- G. Murali
- M.p. Salaimanimagudam
- Roman Fediuk
- Hakim Abdelgader
- A. Siva
2021 Structures
The performance of novel Layered Two Stage Fibrous Composite slabs (LTSFC) was pioneered under falling mass collisions using a combined experimental and numerical study. Such LTSFC slabs consist of three layers with and without the insertion of glass fibre mesh between the layers. LTSFC techniques were used to fabricate the composite slabs with three layers including 3%, 1.5%, and 3% of fibre content for the top, middle, and bottom layers respectively. Sixteen MLPAFC square slabs were cast with only short hooked end fibres and tested under falling mass collisions by amending two parameters namely the type of support (fixed and hinge) and support layout. Two distinct support layouts on two types of support were considered and tested with and without the glass fibre mesh between layers of LTSFC. A glass fibre mesh was introduced between the three layers to block crack growth propagation and absorb additional collision energy. The glass fibre mesh insertion between the layers and the LTSFC production technique were considered as novel modifications. A numerical study using Auto desk Fusion 360 was conducted and compared with experimental results. The numerical results showed fair agreement with the experimental test results. Based on the validated numerical models, collision energy and cracking pattern evolution were studied. The findings indicated that the glass fibre mesh insertion between the layers combined with steel fibres disrupted crack proliferation, thus exhibiting superior engrossed collision energy and postponing crack growth. Additionally, the engrossed collision energy at crack initiation and ultimate crack for the slabs with four sides fixed and hinged support were greater with respect to two opposite sides fixed and hinged support. Numerical values were in reasonable agreement with the experimental values in terms of collision energy and cracking patterns.
imPlatelet classifier: image‐converted RNA biomarker profiles enable blood‐based cancer diagnostics
- Krzysztof Pastuszak
- Anna Supernat
- Myron G Best
- Sjors In ‘t Veld
- Sylwia Łapińska‐Szumczyk
- Anna Łojkowska
- Robert Różański
- Anna Żaczek
- Jacek Jassem
- Thomas Würdinger
- Tomasz Stokowy
2021 Pełny tekst Molecular Oncology
Liquid biopsies offer a minimally invasive sample collection, outperforming traditional biopsies employed for cancer evaluation. The widely used material is blood, which is the source of tumor-educated platelets. Here, we developed the imPlatelet classifier, which converts RNA-sequenced platelet data into images in which each pixel corresponds to the expression level of a certain gene. Biological knowledge from the Kyoto Encyclopedia of Genes and Genomes was also implemented to improve accuracy. Images obtained from samples can then be compared against standard images for specific cancers to determine a diagnosis. We tested imPlatelet on a cohort of 401 non-small cell lung cancer patients, 62 sarcoma patients and 28 ovarian cancer patients. imPlatelet provided excellent discrimination between lung cancer cases and healthy controls, with accuracy equal to 1 in the independent dataset. When discriminating between non-cancer cases and sarcoma or ovarian cancer patients, accuracy equaled 0.91 or 0.95, respectively, in the independent datasets. According to our knowledge, this is the first study implementing an image-based deep-learning approach combined with biological knowledge to classify human samples. The performance of imPlatelet considerably exceeds previously published methods and our own alternative attempts of sample discrimination. We show that the deep-learning image-based classifier accurately identifies cancer, even when a limited number of samples is available.
Implementacja wykrywalnych usług typu REST na platformie Jakarta EE
- Michał Wójcik
2021
Niniejszy rozdział przedstawia propozycję w jaki sposób może być realizowana implementacja wykrywalnych usług sieciowych opartych na stylu architektonicznym REST na platformie Jakarta EE. Zostały tutaj przedstawione zarówno podstawy teoretyczne niezależne od zastosowanej platformy technologicznej, jak i szczegóły implementacji w technologii JAX-RS wchodzącej w skład platformy Jakarta EE. W szczególności zostały tutaj przedstawione sposoby poprawnego budowania hierarchicznego API zgodnie z modelem dojrzałości Richardsona jak i techniki opisywania reprezentacji zwracanej przez usługi sieciowe zgodnie ograniczeniem HATEOAS i językiem opisu HAL. Wszystkie aspekty teoretyczne poruszane w rozdziale zostały poparte praktyczną implementacją dostępną publicznie w postaci repozytorium kodu opartego na systemie kontroli wersji Git.