2022 - Repozytorium publikacji - Politechnika Gdańska

Pokaż publikacje z roku

Publikacje z roku 2022

Pokaż wszystkie

Labour resources in Kazakhstan and Uzbekistan - a comparative study
- Krystyna Gomółka
2022
The aim of the paper is to show the transformation and comparison of labour resources in Kazakhstan and Uzbekistan using the following methods: deductive data analysis, observation of changes in the structure of resources based on publicly available macroeconomic data. During the two decades of the 21st century, both countries experienced population growth which translated into an increased number of persons of working age. In both countries, men were more active in the labour market and more than half of women were inactive. Both countries have seen an increase in the gross enrolment ratio at primary and secondary levels. In Kazakhstan the number of people with higher education fluctuated and in Uzbekistan it slowly increased. Unemployment decreased in both countries as a result of growing economy and economic migration. The net migration rate in both countries was negative, which affected the countries' labour resources.
Landscape of Automated Log Analysis: A Systematic Literature Review and Mapping Study
- Łukasz Korzeniowski
- Krzysztof Goczyła
2022 Pełny tekst IEEE Access
Logging is a common practice in software engineering to provide insights into working systems. The main uses of log files have always been failure identification and root cause analysis. In recent years, novel applications of logging have emerged that benefit from automated analysis of log files, for example, real-time monitoring of system health, understanding users’ behavior, and extracting domain knowledge. Although nearly every software system produces log files, the biggest challenge in log analysis is the lack of a common standard for both the content and format of log data. This paper provides a systematic review of recent literature (covering the period between 2000 and June 2021, concentrating primarily on the last five years of this period) related to automated log analysis. Our contribution is three-fold: we present an overview of various research areas in the field; we identify different types of log files that are used in research, and we systematize the content of log files. We believe that this paper serves as a valuable starting point for new researchers in the field, as well as an interesting overview for those looking for other ways of utilizing log information.
Language Models in Speech Recognition
- Jan Daciuk
2022
This chapter describes language models used in speech recognition, It starts by indicating the role and the place of language models in speech recognition. Mesures used to compare language models follow. An overview of n-gram, syntactic, semantic, and neural models is given. It is accompanied by a list of popular software.
Lanthanide-organic-frameworks modified ZnIn2S4 for boosting hydrogen generation under UV–Vis and visible light
- Jakub Sowik
- Tomasz Grzyb
- Grzegorz Trykowski
- Tomasz Klimczuk
- Kostiantyn Nikiforow
- Onur Cavdar
- Adriana Zaleska-Medynska
- Anna Malankowska
2022 INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
Novel Ln-MOF with microrods shape were successfully combined with ZnIn2S4 (ZIS) microsphere and used for photocatalytic hydrogen generation under UV–Vis and visible light. The Ln-MOFs/ZIS system comprises lanthanide-carboxylate coordination networks (Tm and Gd as metal ions, and 1,3,5-benzenetricarboxylic acid (BTC) as the organic linker) deposited on ZnIn2S4 microspheres. Effect of the amount of ((Tm,Gd)-BTC) (1, 5, 10 wt%) on the optical properties and photocatalytic hydrogen evolution performance was investigated. ZIS microsphere shows the marigold flower-like morphology and hexagonal polytopic crystal form. Our results proved that the combination of ZIS microsphere, Ln-MOF and Pt nanoparticles (NPs) caused significant enhancement in hydrogen generation. Amount of formed hydrogen was raised from 196.3 to 7782.1 μmol g−1 for pristine ZIS and ZIS decorated with 1% (Tm, Gd)-BTC/Pt under UV–Vis light, respectively.
Laplace domain BEM for anisotropic transient elastodynamics
- Ivan Markov
- Leonid A. Igumnov
- Alexander Belov
- Victor Eremeev
2022 Pełny tekst MATHEMATICS AND MECHANICS OF SOLIDS
In this paper, we describe Laplace domain boundary element method (BEM) for transient dynamic problems of three-dimensional finite homogeneous anisotropic linearly elastic solids. The employed boundary integral equations for displacements are regularized using the static traction fundamental solution. Modified integral expressions for the dynamic parts of anisotropic fundamental solutions and their first derivatives are obtained. Boundary elements with mixed approximation of geometry and field variables with the standard nodal collocation procedure are used for spatial discretization. In order to obtain time-domain solutions, the classic Durbin’s method is applied for numerical inversion of Laplace transform. Problem of alleviating Gibbs oscillations is addressed. Dynamic boundary element analysis of the model problem involving trigonal material is performed to test presented formulation. Obtained results are compared with finite element solutions.
Laser Beam as a Precision Tool to Increase Fatigue Resistance in an Eyelet of Undercarriage Drag Strut
- Marek Szkodo
- Anna Bień
- Alicja Stanisławska
2022 Pełny tekst International Journal of Precision Engineering and Manufacturing-Green Technology
The article contains the results of tests on a laser-processed eyelet of undercarriage drag strut to increase its fatigue strength. Laser processing concentrated on both sides around the hole of eye for connecting the undercarriage drag strut caused that the material in this area withstood more than twice the number of load cycles established for this material. In order to determine the reasons for the increase in fatigue strength, residual stresses in laser-treated LT areas and in the base metal BM located between melted paths were determined, using the nanoindentation test and Williamson Hall method. The modified Williamson Hall analysis of XRD patterns was also used to determine the dislocation density in both areas. The results indicate that high residual tensile stresses occur in melted areas and in base metal located between melted paths occur high residual compressive stresses. A large increase in hardness and elastic properties, dissolution of non-metallic inclusions, as well as large solid solution and sub-grain strengthening contributed to the high fatigue resistance of the melted areas.
Laser Welding of UNS S33207 Hyper-Duplex Stainless Steel to 6061 Aluminum Alloy Using High Entropy Alloy as a Filler Material
- Dhanesh G. Mohan
- Jacek Tomków
- Sasan Sattarpanah Karganroudi
2022 Pełny tekst Applied Sciences-Basel
The high entropy alloy (HEA) filler used during the fabrication method determines the reliability of HEAs for steel-aluminum dissimilar alloy configuration. HEAs have a direct impact on the formation of intermetallic compounds (IMC) formed by the interaction of iron (Fe) and aluminum (Al), and influence the size of the joint’s interaction zone. A novel welding process for Fe-Al alloy joints was developed to prevent the development of a brittle iron-aluminum interface. This research involved investigation of the possibility of using HEA powdered filler. Fe5Co20Ni20Mn35Cu20 HEAs was used as a filler for the laser joining lap configuration joining hyper-duplex stainless steel UNS S33207 to aluminum alloy 6061. This HEA has unique properties, such as high strength, good ductility, and high resistance to corrosion and wear. A tiny portion of the stainless-steel area was melted by varying the welding parameters. The high-entropy alloy (HEA) with slow kinetic diffusion and large entropy was employed to aid in producing solid solution structures, impeding the blending of iron and aluminum particles and hindering the development of Fe-Al IMCs. The weld seam was created without the use of Fe-Al IMCs,. The specimen broke at the HEAs/Al alloy interface with a tensile-shear strength of 237 MPa. The tensile-shear strength achieved was 12.86% higher than for the base metal AA 6061 and 75.57% lower than for the UNS S33207 hyper-duplex stainless steel.
Lateral forces determine dimensional accuracy of the narrow‑kerf sawing of wood
- Kazimierz Orlowski
- Daniel Chuchala
- Marcin Szczepanski
- Wojciech Migda
- Wiktoria Wojnicz
- Jakub Sandak
2022 Pełny tekst Scientific Reports
The shrinking global forest area limits the supply of industrially usable raw resources. This, in combination with the ever‑increasing consumption of timber due to population growth can lead to the lack of a positive balance between the annual volumetric growth and consumption of wood. An important innovation toward increasing environmental and economic sustainability of timber production is to reduce the volume of wood residues by minimizing the sawing kerf. It results in higher material yield but may impact the dimensional accuracy of derived products. Therefore, the cutting tool geometry as well as the sawing process as a whole must be carefully optimized to assure optimal use of resources. The goal of this study is to better understand the causes of machining errors that occur when sawing wood with saws of varying thickness of kerf, with a special focus on re‑sawing thin lamellae performed on the gang saw. Numerical simulations were tested against experimental results, considering influence of diverse components of cutting forces, in addition to the initial and operating stiffness coefficients of the saw blade. It has been demonstrated that asymmetric loads from the cutting process for the scraper saw blade can cause sawing inaccuracies. The simulation methodology developed in this research can be straightforwardly extended towards determination of optimal geometry of other cutting tools, particularly with the reduced sawing kerf. This may lead to more sustainable use of natural resources as well as an increase in economic gain for the wood processing industries.
Layer-by-layer polymer deposited fabrics with superior flame retardancy and electrical conductivity
- S. Ehsanimehr
- R. Sonnier
- P. Najafi
- Franck Ducos
- Michael Badawi
- Krzysztof Formela
- Mohammad Saeb
- Henri Vahabi
2022 REACTIVE & FUNCTIONAL POLYMERS
Smart and multifunctional textiles and fabrics are progressively developing, such that multifunctional fabrics are becoming more widespread. We elaborated herein multi-layered flax fabrics with superior flame retardancy and conductivity, which revealed fireproof feature while keeping conductivity during burning. The flax fabric was reinforced by layer-by-layer (LbL) deposition of sodium polyacrylate (SPA), polyethylenimine (PEI), ammonium polyphosphate (APP), and lastly a composite having poly(aniline-co-melamine) and montmorillonite (MMT) coated the aforementioned layers. The resulting multi-layered fabrics were characterized systematically by Fourier-transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), energy dispersive X-ray spectrometry (EDX) and thermogravimetric analysis (TGA). Flame retardancy of fabrics was conducted on pyrolysis-combustion flow calorimetry (PCFC), and a vertical burning test. TGA test showed a significant increase in the amount of residue of the treated fabrics (37%) against 19% assigned to untreated flax fabrics. Surprisingly, PCFC showed a very low peak of heat release rate (pHRR) of 15 W/g (HRR) for reinforced flax fabrics with respect to 234 W/g assigned to untreated flax fabrics (≈ −94%). In addition, the vertical burning test demonstrated the fireproof character of multi-layered fabrics. The conductivity of coated flax fabric was in the range of 1–8 × 10−7 S/cm before burning, which astonishingly survived up to 30 s after burning. This bi-functional flame retardant and conductive fabric enables taking next steps towards development of fireproof conductive materials for advanced technologies.
Layered Morphology of Gdansk: Past, Present and Future.
- Saira Abbasi
- Nirmiti Sutar
- Małgorzata Kostrzewska
- Łukasz Bugalski
- Justyna Martyniuk-Pęczek
2022 Pełny tekst
This study aims to analyze the urban fabric and form of the city of Gdańsk based on the Muratorian and Italian school of urban morphology, to deepen the understanding of the morphological process of the urban fabric. It can be seen that the urban fabric of the city is a juxtaposition of all these layers, and based on Muratori’s approach these are indicative of not just the past, present but also the future. The study sample is of the oldest areas of Gdansk that are identified to be dated from 10th to 16th Century and is known as Stare Miasto meaning Old Town. Analysis is based on the study of existing literature, historical archives, cartography and maps. It is seen that the surroundings of the Gdansk city center have changed, and a number of elements that were destroyed were not reconstructed. Minor shifting of matrix routes and development of new poles and nodes are visible, but the primary formation of matrix route visible from the 16th Century remains constant. The research identifies that the nodes, as well as, the edges of the historic city play an integral part in the shaping the urban tissue and form. Furthermore, the river and its shape act as edges as well, and the changes in the shape of the river influence the shape of the urban form.
Le reti della terza Italia.Imprese, calcio, sponsirzzazioni e territorio in Serie B 81982-2006)
- Luciano Segreto
2022
Il capitolo si occupa dei rapporti tra imprese e sponsirzzazioni dei club calcistici italiani della serie B tra il 1982 e il 2006
Lead In drinking water: Adsorption method and role of zeolitic imidazolate frameworks for its remediation: A review
- Khalil Ahmad
- Habib-ur-Rehman Shah
- Muhammad Khan
- Amjad Iqbal
- Erich Potrich
- Larissa Souza Amaral
- Sidra Rasheed
- Haq Nawaz
- Asif Ayub
- Khalida Naseem
- Ali Muhammad
- Ashfaq Muhammad
2022 JOURNAL OF CLEANER PRODUCTION
Due to various characteristics properties lead(II) metal is utilized in many applications like lead ion batteries, water pipes, ammunition and paints. For this reason, concentration of lead(II) ions in water is increasing days by days which is alarming for water pollution. Water pollution is a major problem worldwide which affects biosphere badly, and causes continuous reduction of accessible sources of fresh water and ground water, available for drinking purpose. From these pollutants lead is highly toxic metal which badly affects humans as well as aquatic organisms. Due to its toxic and non-degradable nature, it is listed in top ten hazardous metals. Various adsorbents are applied for removal of lead from water. Recently, Zeolitic Imidazolate Frameworks a subclass of Metal Organic Frameworks introduced by Yaghi group having outstanding stability and porosity are applied for removal of lead from water using adsorption method as reported in many studies. In this review recent progresses for removal of lead from water by adsorption method using ZIF-8 and ZIF-67 MOFs are discussed in detail. Adsorption mechanism includes electrostatic/coordination interactions, π-π-stacking and ion exchange method for lead removal from aqueous medium are discussed in detail. Pseudo 2nd order-equation and Langmuir model are well fitted for elucidation of adsorption mechanism for lead removal.
Lead-free bismuth-based perovskites coupled with g–C3N4: A machine learning based novel approach for visible light induced degradation of pollutants
- Magdalena Miodyńska
- Alicja Mikolajczyk
- Paweł Mazierski
- Tomasz Klimczuk
- Wojciech Lisowski
- Grzegorz Trykowski
- Adriana Zaleska-Medynska
2022 APPLIED SURFACE SCIENCE
The use of metal halide perovskites in photocatalytic processes has been attempted because of their unique optical properties. In this work, for the first time, Pb-free Bi-based perovskites of the Cs3Bi2X9 type (X = Cl, Br, I, Cl/Br, Cl/I, Br/I) were synthesized and subjected to comprehensive morphological, structural, and surface analyses, and photocatalytic properties in the phenol degradation reaction were examined. Furthermore, the most promising Pb-free Bi-based Cs3Bi2X9 perovskites (i.e., structures that present an optimal combination of structural features and efficiency) were selected using a machine learning based virtual screening methodology and enriched with the C3N4 composite. The selected and designed Cs3Bi2 (Cl/Br)9 structures were in line with the “safe and sustainable by design” approach and applied for the first time in the aforementioned reaction, which allowed for approximately 84% efficiency under visible light. The main merit of this achievement was the optimum deposition of perovskite Cs3Bi2(Cl/Br)9 (5 wt%) on the C3N4 matrix, which resulted in approximately a two-fold increase in the apparent quantum efficiency of the composite compared with that of bare C3N4 (at an excitation wavelength of 430 nm).
Lessons learned during SRAD hybrid motor development
- Mateusz Czapski
- Norbert Szulc
- Julia Godlewska
- Wiktor Lachowski
- Natalia Balogh
- Wojciech Deszczyński
- Krzysztof Hucik
- Kacper Zieliński
- Dariusz Kardaś
- Anna Rusin
- Maja Kaszuba
- Wiktor Sieklicki
2022 Pełny tekst
Student Researched and Developed (SRAD) hybrid rocket motor H-15 with total impulse of 15 $kNs$ was built. First version of the engine has average thrust of 3 $kN$, the second, improved one is prepared with an aim to have average thrust of 5 $kN$. Engine development was started from scratch and went through phases of: definition of design assumptions and constraints, numerical modelling to predict engine performance, CAD and CAM models preparation, manufacturing and static testing. Outcomes and conclusions of each phase will be presented, as well as development decisions which were the result of engine testing. H-15 employs nitrous oxide as an oxidizer and polypropylene and polyamide as fuels. This selection of materials was chosen due to their relative ease of preparation and wide availability. The engine was built by SimLE student organisation, form Gdansk University of Technology (Gdansk, Poland). SimLE is one of the largest organisations at GUT which brings together students interested in many aspects of aerospace engineering. The reason for hybrid rocket propulsion development was participation in international rocketry competitions, such as Spaceport America Cup and European Rocketry Challenge. The goal of these contests is delivering 4 $kg$ of payload to an altitude of 3000 $m$ by a sounding rocket. Conclusions from the engine development process will be discussed, as well as perspectives for further development of our engine.
Lessons learned from developing an Industry 4.0 mobile process management system supported by Artificial Intelligence
- Mateusz Kalinowski
- Paweł Weichbroth
2022 Pełny tekst Informatyka Ekonomiczna. Prace Naukowe Uniwersytetu Ekonomicznego we Wrocławiu
Research, development and innovation (RDI) projects are undertaken in order to improve existing, or develop new, more efficient products and services. Moreover, the goal of innovation is to produce new knowledge through research, and disseminating it through education and training. In this line of thinking, this paper reports and discusses the lessons learned from the undertaken project, regarding three areas: machine learning (artificial intelligence), computational intelligence, and database management systems (DBMS). As nowadays, a numerous of the RDI projects are oriented towards the development of data intensive solutions, the authors are confident that these lessons will be valuable not only for data engineers, but also for those researchers and practitioners who are dealing with the issues related to building and validating machine learning models, applications of moving averages to high-frequency data streams, and the implementation and deployment of DBMS.
Li nucleation on the graphite anode under potential control in Li-ion batteries
- Arihant Bhandari
- Chao Peng
- Jacek Dziedzic
- John R. Owen
- Denis Kramer
- Chris-Kriton Skylaris
2022 Pełny tekst Journal of Materials Chemistry A
Application of Li-ion batteries in electric vehicles requires improved safety, increased lifetime and high charging rates. One of the most commonly used intercalation anode material for Li-ion batteries, graphite, is vulnerable to Li nucleation, a side reaction which competes with the intercalation process and leads to loss of reversible capacity of the battery, ageing and short-circuits. In this study, we deploy a combined grand canonical large-scale electronic density-functional theory (DFT) and Poisson–Boltzmann electrolyte theory to study the nucleation and growth of Li clusters on the graphite anode in the presence of its surrounding electrolyte environment at different applied voltages with respect to the Li metal reference electrode. We find the voltage below which the nucleation energy becomes negative (corresponding to Li nucleation becoming energetically favourable), the ‘potential of zero nucleation energy’ (UPZN). We observe a distinct minimum in the plots of UPZN as a function of the size of nucleated clusters. When the applied voltage on the graphite electrode is below the minimum value of UPZN, the nucleated clusters start growing unbounded on graphite electrode. This potential for cluster growth (UPCG) is found to be -0.12 V on the periodic basal plane of unlithiated graphite and -0.08 V on lithiated graphite. The corresponding potential for the zigzag edge termination is -0.06 V on unlithiated graphite and -0.04 V on lithiated graphite. Thus, the nucleation and cluster growth is favored on the zigzag edge termination of the graphite electrode as compared to the periodic basal plane and on the lithiated graphite as compared to the unlithiated graphite. We find that the surrounding environment plays a significant role and that nucleation is more likely to occur in electrolyte environment than that predicted from calculations in vacuum. We observe that the potentials obtained with grand canonical ensemble DFT method in electrolyte are close to experimentally available data. The study has profound implications for the nucleation, growth and control of metal dendrites in a battery cell.
Light intensity analysis of photovoltaic parameters for perovskite solar cells
- Damian Głowienka
- Yulia Galagan
2022 Pełny tekst ADVANCED MATERIALS
The number of publications on perovskite solar cells (PSC) continues to grow exponentially. Although the efficiency of PSC is exceeded 25.5%, not every research laboratory can reproduce this result or even pass the border of 20%. Unfortunately, it is not always clear which dominating mechanism is responsible for the performance drop. Here, we develop a simple method of light intensity analysis of JV parameters allowing the understanding what are the mechanisms appearing in the solar cell and limiting device performance. The developed method is supported by the drift-diffusion model and aimed to help in the explanation of the parasitic losses from the interface or bulk recombination, series, or shunt resistance in the perovskite solar cell. This method can help not only point on the dominating of bulk or interface recombination in the devices but also determine which interface is more defective. The detailed and stepwise guidance for such a type of light intensity analysis of JV parameters is provided. The proposed method and the conclusions of this study are supported by a series of case studies, showing the effectiveness of the proposed method on real examples.
Light4Health eLearning Course: health research for interior lighting design. Re-thinking design approaches based on science
- Karolina Zielińska-Dąbkowska
2022 Pełny tekst
This paper presents the results of 'Light4Health' (L4H), a three-year EU Erasmus+ Strategic Partnership grant project (2019-2021), which investigated, systematized and taught health-related research on the impact of natural and artificial light on human health and well-being relevant to indoor lighting design. The objective was to re-think evidence-based lighting design approaches for residential, working/educational, and healthcare spaces, in order to develop a novel cross-disciplinary eLearning platform, that intersects lighting design and current peer-reviewed health research through a select combination of the most relevant research, methods, and tools. The content was developed through teaching workshops with international researchers, teachers, and students. Participating students were introduced to the application of relevant research and new metrics, in order to produce creative lighting design proposals. Students were able to inform lighting design approaches that support health and well-being without compromising creativity via the tools and methods developed through the health sciences. With this project, participants and consortium members have narrowed the gap that exists between research and the practice/application of lighting, by translating research from complex scientific jargon into various tools for designers to use. The knowledge gained, was consolidated into an open-access online curriculum for international lighting design students, educators and professionals via the free eLearning Moodle platform (https://course.light4health.net/).
Light‐Driven Multi‐Charge Separation in a Push‐Pull Ruthenium‐Based Photosensitizer – Assessed by RASSCF and TDDFT Simulations
- Stephan Kupfer
- Maria WäCHTLER
- Julien Guthmuller
2022 Pełny tekst ChemPhotoChem
The performance of photosensitizers in the field of, for example, solar energy conversion, relies on their light-harvesting efficiency in the visible region, population of long-lived charge separated intermediates, as well as their charge-accumulation capacity amongst other properties. In this computational study, we investigate the photophysical properties of a bis(bipyridyl)ruthenium(II)-based black dye (Ru) incorporating a chromophoric unit based on a thiazole donor-acceptor pushpull motif. The combination of two light-harvesting units, that is, the Ru(II)polypyridyl and the thiazole-based organic dye, yields close-lying metal-to-ligand charge transfer (MLCT) states, involving both ligand spheres as well as intra-ligand charge transfer (ILCT) states of the organic dye. Due to the combination of inorganic and organic chromophores the computational modelling of the photophysics of Ru is challenging. To this aim, time-dependent density functional theory and multiconfigurational methods are applied. The excited-state properties obtained for the states of interest are rationalized by electronic absorption and resonance Raman spectroscopies. The CAMB3LYP functional was found to accurately describe the ground and excited-state properties of Ru. Finally, excited-state relaxation pathways and the multi-charge-accumulation capacity were addressed. Despite the unidirectional nature of the MLCTthia and ILCTthia transitions, the thiazole unit is merely capable to store one redox equivalent.
Lighting conditions in Home Office and occupant’s perception: an international study
- Cláudia Naves David Amorim
- Natalia Giraldo Vasquez
- Barbara Matusiak
- Julia Kanno
- Natalia Sokół
- Justyna Martyniuk-Pęczek
- Sergio Sibilio
- Yasuko Koga
- Giovanni Ciampi
- Marta Waczyńska
2022 Pełny tekst ENERGY AND BUILDINGS
The global pandemic and physical distancing restrictions are forcing us to rethink how residential buildings are used regarding the visual environment. This paper describes home office lighting conditions within different countries and continents. The aim is to define the current limitations of home offices in providing a resilient visual environment. The work was developed by a team of international experts working together on Subtask A: User perspective and requirements, in International Energy Agency IEA SHC Task 61/EBC Annex 77 “Integrated Solutions for Daylighting and Electric Lighting”. The method included an international online survey in 6 countries in South America, Europe and East Asia containing 37 questions about general data, physical characteristics of the home office and occupant’s perception, behaviour and needs regarding the visual environments, and photos taken by the occupants. Descriptive statistics, inspection of the photos, and qualitative analysis from the open-ended question were performed. In total, 694 responses and 453 photos were analysed, making it possible to identify the occupants’ perceptions about the lighting and visual environment in the home offices both for professionals and students. The results indicate cultural differences in styles of residential buildings and interiors, in the custom of using lighting, and between continents and occupational categories. Possible improvements are suggested.