2021 - Repozytorium publikacji - Politechnika Gdańska

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Data set generation at novel test-rig for validation of numerical models for modeling granular flows
- Agata Widuch
- Kari Myöhänen
- Markku Nikku
- Marcin Nowak
- Adam Klimanek
- Wojciech Adamczyk
2021 Pełny tekst INTERNATIONAL JOURNAL OF MULTIPHASE FLOW
Significant effort has been exerted on developing fast and reliable numerical models for modeling particulate flow; this is challenging owing to the complexity of such flows. To achieve this, reliable and high-quality experimental data are required for model development and validation. This study presents the design of a novel test-rig that allows the visualization and measurement of particle flow patterns during the collision of two particle streams. Valuable data sets are provided for the validation of numerical models dedicated to granular flows. The experimental work was conducted for three particle distributions and different configurations of the test rig setup. Additionally, a standard discrete element method for modeling particle transport was applied to the test-rig configuration and the effects of the material spring constant on the predicated flow patterns are investigated. An additional purpose of these simulations was also to collect necessary data for further collision model validation, developed based on a reduced-order technique.
DC and AC Conductivity, Biosolubility and Thermal Properties of Mg-Doped Na2O–CaO–P2O5 Glasses
- Natalia Wójcik
- Sharafat Ali
- Jakub Karczewski
- Bo Jonson
- Michał Bartmański
- Ryszard Barczyński
2021 Pełny tekst Materials
Bioactive glasses have recently been extensively used to replace, regenerate, and repair hard tissues in the human body because of their ability to bond with living tissue. In this work, the effects of replacing Na2O with MgO on the electrical, biosolubility, and thermal properties of the target glass 10Na2O–60P2O5–30CaO (in mol%) were investigated. The electrical properties of the glasses were studied with the impedance spectroscopy technique. At 473 K, DC conductivity values decreased from 4.21*10−11 to 4.21*10−12 S cm−1 after complete substitution of MgO for Na2O. All samples had a similar activation energy of the DC conduction process ~1.27 eV. Conduction mechanisms were found to be due to hop of ions: Na+, Mg2+, and probable H+. FTIR analysis showed that, as the Mg content increased, the Q2 unit (PO2‐) shifted towards higher wavenumbers. The proportion of Q3 unit (P2O5) decreased in the glass structure. This confirmed that the replacement of Na+ by Mg2+ was accompanied by concurrent polymerization of the calcium–phosphate glass network. The biosolubility test in the phosphate‐buffered saline solution showed that the magnesium addition enhanced the biosolubility properties of Na2O–CaO–P2O5 glasses by increasing their dissolution rate and supporting forming CaP‐rich layers on the surface. The glass transition temperature increased, and thermal stability decreased substantially upon substitution of Na2O by MgO.
Decoupled Kalman filter based identification of time-varying FIR systems
- Marcin Ciołek
- Maciej Niedźwiecki
- Artur Gańcza
2021 Pełny tekst IEEE Access
When system parameters vary at a fast rate, identification schemes based on model-free local estimation approaches do not yield satisfactory results. In cases like this, more sophisticated parameter tracking procedures must be used, based on explicit models of parameter variation (often referred to as hypermodels), either deterministic or stochastic. Kalman filter trackers, which belong to the second category, are seldom used in practice due to difficulties in adjusting their internal parameters such as the smoothness coefficient and the order of the hypermodel. The paper presents a new solution to this problem, based on the concept of preestimation of system parameters. The resulting identification algorithms, which can be characterized as decoupled Kalman trackers, are computationally attractive, easy to tune and can be optimized in an adaptive fashion using the parallel estimation approach. The decoupled KF algorithms can be regarded as an attractive alternative to the state-of-the-art algorithms which are much more computationally demanding.
Deep eutectic solvent based method for analysis of Niclosamide in pharmaceutical and wastewater samples – A green analytical chemistry approach
- Noor Faraz
- Hameed Haq
- Muhammad Balal
- Roberto Castro-Muñoz
- Grzegorz Boczkaj
- Asif Khan
2021 Pełny tekst JOURNAL OF MOLECULAR LIQUIDS
The paper presents a simple, but very effective and sensitive spectrophotometric method for trace analysis of Niclosamide based on liquid–liquid microextraction using deep eutectic solvents (DESs) prior to its quantification. Here, different DES systems, such as Choline chloride (ChCl) + Urea, ChCl + Citric acid, ChCl + Ethylene glycol and ChCl + Phenol, were synthesized and evaluated at different molar ratios, selecting ChCl + Phenol 1:2 as an extractive DES system. Optimization studies revealed that best performance were obtained at pH 8 with optimum volume of THF and DES as 0.3 mL and 0.4 mL, respectively. The developed method is characterized by good analytical performance, e.g., a recovery of 99.26% and precision described by RSD value as <2%. The inter-assay precision was 0.51% while intermediate precision was 0.0323%. The method was found linear from 4.8 to 48 µg/L. LOD and LOQ were found as 0.112 and 0.374 µg/L, respectively. The paper presents also examples of the application of the proposed method for the determination of Niclosamide in different pharmaceutical and wastewater samples. This alternative method reveals a better performance in respect to the British pharmacopoeia procedure, providing concurrently ease of operation and simplicity.
Deep eutectic solvents – based green absorbents for effective volatile organochlorine compounds removal from biogas
- Patrycja Makoś-Chełstowska
- Edyta Słupek
- Jacek Gębicki
2021 Pełny tekst GREEN CHEMISTRY
Volatile organochlorine compounds (VOXs) presented in biogas can cause many technological and environmental problems. During the combustion of biogas containing VOXs, the corrosion of installation, as well as the formation of toxic by-products (polyhalogenated dioxins and furans) and further emission to the atmosphere, may occur. Therefore, in this study, a new procedure based on physical absorption was developed. In order to meet the requirements of green chemistry and green engineering, new deep eutectic solvents (DESs) composed of natural components were used in the absorption studies. Several physical properties of new DESs were determined, followed by an explanation of the absorbents formation mechanism, by means of spectroscopic analysis, and density functional theory. The most important absorption parameters i.e. type of DES, gas flowrate, kind of matrix gas, temperature, and initial concentrations of VOXs were optimized. The obtained results indicate that DES composed of syringol and levulinic acid in 1:1 molar ratio could absorb VOXs efficiently. In addition, the DES regeneration studies demonstrated that the absorption capacities of DES did not change after ten absorption-desorption cycles. Studies on the absorption mechanisms indicate that the H-bonding and van der Waals interactions are the main driving force for the VOXs removal from biogas.
Deep eutectic solvents based assay for extraction and determination of zinc in fish and eel samples using FAAS
- Hameed Haq
- Muhammad Balal
- Roberto Castro-Muñoz
- Zahid Hussain
- Faisal Safi
- Sana Ullah
- Grzegorz Boczkaj
2021 Pełny tekst JOURNAL OF MOLECULAR LIQUIDS
A new assay based on effective (high recovery) extraction by means of deep eutectic solvents (DESs) was developed for ppb level determination of zinc in fishes and eel samples. Choline chloride and Phenol in a 1:2 M ratio was selected as optimal DES-based extraction solvent. 8-Hydroxy quinoline was used as a chelating agent for zinc ions. The optimized conditions were found at pH value of 8, ligand concentration of 10 mg/L, THF volumetric ratio in bulk solution of 0.5:10. The total time at optimal sample preparation conditions was 5 min for digested sample. Developed method fits to the purpose of routine analysis of fishes and eels. The LOD and LOQ were found 0.041 μg/kg and 0.136 μg/kg with pre-concentration factor of 25 and RSD 1.7%.
Deep Learning
- Semra Erpolat Tasabat
- Olgun Aydin
2021
Deep learning (DL) is a rising star of machine learning (ML) and artificial intelligence (AI) domains. Until 2006, many researchers had attempted to build deep neural networks (DNN), but most of them failed. In 2006, it was proven that deep neural networks are one of the most crucial inventions for the 21st century. Nowadays, DNN are being used as a key technology for many different domains: self-driven vehicles, smart cities, security, automated machines. In this chapter, brief information about DL theory is given, advantages and disadvantages of deep learning are discussed, most used types of DNN are mentioned, popular DL architectures and frameworks are glanced and aimed to build smart systems for the finance and real estate domains. Finally, a case study about image recognition using transfer learning is developed.
Deep Learning: A Case Study for Image Recognition Using Transfer Learning
- Semra Erpolat Tasabat
- Olgun Aydin
2021
Deep learning (DL) is a rising star of machine learning (ML) and artificial intelligence (AI) domains. Until 2006, many researchers had attempted to build deep neural networks (DNN), but most of them failed. In 2006, it was proven that deep neural networks are one of the most crucial inventions for the 21st century. Nowadays, DNN are being used as a key technology for many different domains: self-driven vehicles, smart cities, security, automated machines. In this chapter, brief information about DL theory is given, advantages and disadvantages of deep learning are discussed, most used types of DNN are mentioned, popular DL architectures and frameworks are glanced and aimed to build smart systems for the finance and real estate domains. Finally, a case study about image recognition using transfer learning is developed.
Deep learning for ultra-fast and high precision screening of energy materials
- Zhilong Wang
- Qingxun Wang
- Yanqiang Han
- Yan Ma
- Hua Zhao
- Andrzej Nowak
- Jinjin Li
2021 Energy Storage Materials
Semiconductor materials for energy storage are the core and foundation of modern information society and play important roles in photovoltaic system, integrated circuit, spacecraft technology, lighting applications, and other fields. Unfortunately, due to the long experiment period and high calculation cost, the high-precision band gap (the basic characteristic parameter) of semiconductor is difficult to obtain, which hinders the development of new semiconductor materials. Since the traditional Perdew–Burke–Ernzerhof (PBE) functional not only requires a long calculation time, but also significantly underestimates the band gap, we developed a deep learning model that can predict the more precise Heyd–Scuseria–Ernzerhof (HSE06) band gaps in milliseconds for 1,503 binary metallic oxides, nitrides, and sulfides, with a mean absolute error (MAE) of 0.35 eV, a mean squared error (MSE) of 0.21 eV, and a coefficient of determination (R 2 ) of 0.98. Based on transfer learning, only < 5% of the data set (64 structures) was required to train the model and predict the band gaps of the remaining 1,439 structures. From the 1,503 candidate materials, we quickly identified 75 carrier transport materials, 33 electrode and electrocatalytic materials, 299 power switching materials, and 114 sensing materials. This work is the first to demonstrate the feasibility of transfer learning in band gap prediction, from the low-level PBE to the high-level HSE06 calculation, with a computation speed at least 10 4 times faster than the ab initio calculation. The proposed method could be further expanded to incorporate entire organic/inorganic crystal materials databases ( > 10 6 crystals), which is of great significance for the screening and discovery of new semiconductor energy storage materials. 1.
Defining a novel domain that provides an essential contribution to site-specific interaction of Rep protein with DNA
- Katarzyna Wegrzyn
- Elzbieta Zabrocka
- Katarzyna Bury
- Bartlomiej Tomiczek
- Miłosz Wieczór
- Jacek Czub
- Urszula Uciechowska
- María Moreno-del Alamo
- Urszula Walkow
- Igor Grochowina
- Rafal Dutkiewicz
- Janusz M. Bujnicki
- Rafael Giraldo
- Igor Konieczny
2021 Pełny tekst NUCLEIC ACIDS RESEARCH
An essential feature of replication initiation proteins is their ability to bind to DNA. In this work, we describe a new domain that contributes to a replication initiator sequence-specific interaction with DNA. Applying biochemical assays and structure prediction methods coupled with DNA–protein crosslinking, mass spectrometry, and construction and analysis of mutant proteins, we identified that the replication initiator of the broad host range plasmid RK2, in addition to two winged helix domains, contains a third DNA-binding domain. The phylogenetic analysis revealed that the composition of this unique domain is typical within the described TrfA-like protein family. Both in vitro and in vivo experiments involving the constructed TrfA mutant proteins showed that the newly identified domain is essential for the formation of the protein complex with DNA, contributes to the avidity for interaction with DNA, and the replication activity of the initiator. The analysis of mutant proteins, each containing a single substitution, showed that each of the three domains composing TrfA is essential for the formation of the protein complex with DNA. Furthermore, the new domain, along with the winged helix domains, contributes to the sequence specificity of replication initiator interaction within the plasmid replication origin.
Defining the smart-city in the context of regenerative design and planning
- Dorota Kamrowska-Załuska
- Gerald Leindecker
- Marielle Ferreira SILVA
- Gulben Calis
- Aleksandar Petrovski
2021
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Defining the thermal conductivity of thermally heterogeneous hollow wall bricks used as elements for increasing the comfort of buildings
- Krzysztof Pawłowski
- Maciej Niedostatkiewicz
2021 Pełny tekst Inżynieria Bezpieczeństwa Obiektów Antropogenicznych
The article presents numerical calculation analysis in the scope of determining thermal conductivity coefficientλeq[W/(m·K)] of thermally heterogeneous hollow bricks of thermally heterogeneous structure (a combinationof structural material with thermal insulation material). Numerical calculations were conducted by means ofprofessional software TRISCO-KOBRU 86, serving thermal circulation analysis in a 2D field in stationary approach.The analyzed hollow wall bricks may be used, for instance, as a structural layer of layered outer walls of a building.In the article also the results of the Uc thermal conductivity coefficient calculations for double-layer walls with theuse of the analyzed hollow wall bricks are presented in regard to thermal requirements.
Definiowany programowo uniwersalny interfejs radiowy inteligentnych urządzeń internetu rzeczy
- Olga Błaszkiewicz
- Jarosław Magiera
- Alicja Olejniczak
- Piotr Rajchowski
- Jarosław Sadowski
- Sławomir Ambroziak
- Krzysztof Cwalina
2021 Przegląd Telekomunikacyjny + Wiadomości Telekomunikacyjne
Intensywny wzrost liczby urządzeń komunikujących się ze sobą na dużym obszarze wymaga opracowywania i realizacji rozwiązań systemowych. Z tego względu organizacja 3GPP zdefiniowała wąskopasmowy interfejs radiowy NB-IoT (Narrowband Internet of Things) będący podsystemem LTE (Long Term Evolution) na potrzeby zastosowań IoT niewymagających dużych przepływności. W niniejszym artykule przedstawiono charakterystykę systemu NB-IoT, a także koncepcję i sposób realizacji opracowywanego definiowanego programowo, uniwersalnego, sprzętowo-programowego frameworku wraz z laboratoryjnym środowiskiem badawczo-pomiarowym. W aktualnym etapie prac zaimplementowano większość warstwy fizycznej łącza w dół i w górę oraz wybrane elementy sterowania dostępem do medium transmisyjnego, które zweryfikowano z użyciem testera radiowego.
Denitrification Process Enhancement and Diversity of the Denitrifying Community in the Full Scale Activated Sludge System after Adaptation to Fusel Oil
- Przemysław Kowal
- Sławomir Ciesielski
- Jeremiah Otieno
- Joanna Majtacz
- Krzysztof Czerwionka
- Jacek Mąkinia
2021 Pełny tekst ENERGIES
Implementation of anaerobic digestion of primary sludge in modern wastewater treatment plants (WWTPs) limits the availability of organic carbon for denitrification in conventional nitrification-denitrification (N/DN) systems. In order to ensure efficient denitrification, dosage of the external carbon source is commonly undertaken. However, application of commercial products, such us ethanol or acetate, greatly increases operational costs. As such, inexpensive and efficient alternative carbon sources are strongly desirable. In this study, the use of the fusel oil, a by-product from the distillery industry, was validated in terms of the denitrification process enhancement and impact on the activated sludge bacterial community structure. The experiment was conducted at a full scale biological nutrient removal facility (210,000 PE), in the set of the two technological lines: the experimental line (where fusel oil was introduced at 45 cm3/m3 dose) and the reference line (without an external carbon source addition). During the experimental period of 98 days, conventional nitrate utilization rate (NUR) measurements were carried out on a regular basis in order to assess the biomass adaptation to the fusel oil addition and denitrification process enhancement. While the NURs remained at a stable level in the reference line (1.4 ± 0.1 mg NO3-N/g VSS·h) throughout the entire duration of the experiment, the addition of fusel oil gradually enhanced the denitrification process rate up to 2.7 mg NO3-N/g VSS·h. Moreover, fusel oil contributed to the mitigation of the variability of NO3-N concentrations in the effluent from the anoxic zone. The bacterial community structure, characterized by 16S rRNA PCR—DGGE and the clone libraries of the genes involved in the denitrification process (nirS and nirK), was comparable between the reference and the experimental line during the entire experimental period. In both analyzed lines, the most frequent occurrence of denitrifiers belonging to the genera Acidovorax, Alcaligenes, Azoarcus, Paracoccus and Thauera was noticed. Our results proved that fusel oil would a valuable substrate for denitrification. The addition of fusel oil enhances the process rate and does not reflect a severe selection pressure on the bacterial community at applicable doses. Practical application of fusel oil generates opportunities for the WWTPs to meet effluent standards and reduce operational costs and optimizing waste management for distillery industry.
Dependence of Power Characteristics on Savonius Rotor Segmentation
- Krzysztof Doerffer
- Janusz Telega
- Piotr Doerffer
- Paulina Hercel
- Andrzej Tomporowski
2021 Pełny tekst ENERGIES
Savonius rotors are large and heavy because they use drag force for propulsion. This leads to a larger investment in comparison to horizontal axis wind turbine (HAWT) rotors using lift forces. A simple construction of the Savonius rotor is preferred to reduce the production effort. Therefore, it is proposed here to use single-segment rotors of high elongation. Nevertheless, this rotor type must be compared with a multi-segment rotor to prove that the simplification does not deteriorate the effectiveness. The number of segments affects the aerodynamic performance of the rotor, however, the results shown in the literature are inconsistent. The paper presents a new observation that the relation between the effectiveness of single- and multi-segment rotors depends on the wind velocity. A single-segment rotor becomes significantly more effective than a four-segment rotor at low wind speeds. At high wind speeds, the effectiveness of both rotors becomes similar.
Design and computational fluid dynamics analysis of the last stage of innovative gas-steam turbine
- Stanisław Głuch
- Paweł Ziółkowski
- Łukasz Witanowski
- Janusz Badur
2021 Pełny tekst Archives of Thermodynamics
Research regarding blade design and analysis of flow has been attracting interest for over a century. Meanwhile new concepts and design approaches were created and improved. Advancements in information technologies allowed to introduce computational fluid dynamics and computational flow mechanics. Currently a combination of mentioned methods is used for the design of turbine blades. These methods enabled us to improve flow efficiency and strength of turbine blades. This paper relates to a new type turbine which is in the phase of theoretical analysis, because the working fluid is a mixture of steam and gas generated in a wet combustion chamber. The main aim of this paper is to design and analyze the flow characteristics of the last stage of gas-steam turbine. When creating the spatial model, the atlas of profiles of reaction turbine steps was used. Results of computational fluid dynamics simulations of twisting of the last stage are presented. Blades geometry and the computational mesh are also presented. Velocity vectors, for selected dividing sections that the velocity along the pitch diameter varies greatly. The blade has the shape of its cross-section similar to action type blades near the root and to reaction type blades near the tip. Velocity fields and pressure fields show the flow characteristics of the last stage of gas-steam turbine. The net efficiency of the cycle is equal to 52.61%.
Design and experimental validation of a single-stage PV string inverter with optimal number of interleaved buck-boost cells.
- Artem Fesenko
- Oleksandr Matiushkin
- Oleksandr Husev
- Dmitri Vinnikov
- Ryszard Strzelecki
- Piotr Kołodziejek
2021 Pełny tekst ENERGIES
Increasing converter power density is a problem of topical interest. This paper discusses an interleaved approach of the efficiency increase in the buck-boost stage of an inverter with unfolding circuit in terms of losses in semiconductors, output voltage ripples and power density. Main trends in the power converter development are reviewed. A losses model was designed and used for the proposed solution to find an optimal number of interleaved cells. It describes static and dynamic losses in semiconductor switches for buck and boost mode. The presented calculation results demonstrate the efficiency of the interleaved approach for photovoltaic system. 1 kW power converter prototype was designed with two parallel dc-dc cells for experimental verification of obtained theoretical results. The experimental results confirm theoretical statements.
Design and implementation of an illumination system to mimic skyglow at ecosystem level in a large‐scale lake enclosure facility
- Andreas Jechow
- Günther Schreck
- Christopher C. M. Kyba
- Stella A. Berger
- Lukas Thuile Bistarelli
- Matthias Bodenlos
- Mark O. Gessner
- Hans‐Peter Grossart
- Franziska Kupprat
- Jens C. Nejstgaard
- Andreas Pansch
- Armin Penske
- Michael Sachtleben
- Tom Shatwell
- Gabriel A. Singer
- Susanne Stephan
- Tim J. W. Walles
- Sabine Wollrab
- Karolina Zielińska-Dąbkowska
- Franz Hölker
2021 Pełny tekst Scientific Reports
Light pollution is an environmental stressor of global extent that is growing exponentially in area and intensity. Artificial skyglow, a form of light pollution with large range, is hypothesized to have environmental impact at ecosystem level. However, testing the impact of skyglow at large scales and in a controlled fashion under in situ conditions has remained elusive so far. Here we present the first experimental setup to mimic skyglow at ecosystem level outdoors in an aquatic environment. Spatially diffuse and homogeneous surface illumination that is adjustable between 0.01 and 10 lx, resembling rural to urban skyglow levels, was achieved with white light‐emitting diodes at a large‐ scale lake enclosure facility. The illumination system was enabled by optical modeling with Monte‐ Carlo raytracing and validated by measurements. Our method can be adapted to other outdoor and indoor skyglow experiments, urgently needed to understand the impact of skyglow on ecosystems.
Design and implementation of the driver system for Hamamatsu C12880MA microspectrometer
- Patryk Sokołowski
- Maciej Wróbel
- Katarzyna Karpienko
2021 Pełny tekst Photonics Letters of Poland
Recent miniaturization developments in devices for spectroscopy have reduced greatly their costs and increased their availability for a wide range of users and applications. This paper presents the design and implementation of a driver system for a Hamamatsu C12880MA microspectrometer. The system implementation was carried out and compared using two independent microcontroller modules: Arduino Uno and STM32F411RE Nucleo. We assessed the microspectrometer system parameters like resolution and integration time, as influenced by the choice of a driver icrocontroller. We present a possible application of this microspectrometer system for measurements of ground coffee beans reflectance for control of coffee roasting.
Design centering of compact microwave components using response features and trust regions
- Anna Pietrenko-Dąbrowska
- Sławomir Kozieł
2021 Pełny tekst ENERGIES
Fabrication tolerances, as well as uncertainties of other kinds, e.g., concerning material parameters or operating conditions, are detrimental to the performance of microwave circuits. Mitigating their impact requires accounting for possible parameter deviations already at the design stage. This involves optimization of appropriately defined statistical figures of merit such as yield. Alt-hough important, robust (or tolerance-aware) design is an intricate endeavor because manufac-turing inaccuracies are normally described using probability distributions, and their quantification has to be based on statistical analysis. The major bottleneck here is high computational cost: for re-liability reasons, miniaturized microwave components are evaluated using full-wave electromag-netic (EM) models, whereas conventionally utilized analysis methods (e.g., Monte Carlo simula-tion) are associated with massive circuit evaluations. A practical approach that allows for cir-cumventing aforementioned obstacles offer surrogate modeling techniques, which has been a dominant trend over the recent years. Notwithstanding, a construction of accurate metamodels may require considerable computational investments, especially for higher-dimensional cases. This paper brings in a novel design centering approach, which assembles forward surrogates founded at the level of response features and trust-region framework for direct optimization of the system yield. Formulating the problem with the use of characteristic points of the system response allevi-ates the issues related to response nonlinearities. At the same time, as the surrogate is a linear re-gression model, a rapid yield estimation is possible through numerical integration of the input probability distributions. As a result, expenditures related to design centering are as low as a few dozens of EM analyses. The introduced technique is demonstrated using three microstrip couplers. It is compared to recently reported techniques, and its reliability is corroborated using EM-based Monte Carlo analysis.