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Monitoring the fracture process of concrete during splitting using integrated ultrasonic coda wave interferometry, digital image correlation and X-ray micro-computed tomography
- Erwin Wojtczak
- Magdalena Rucka
- Łukasz Skarżyński
2022 Pełny tekst NDT & E INTERNATIONAL
The paper deals with the continuous-time monitoring of mechanical degradation in concrete cubes under splitting. A series of experiments performed with integrated coda wave interferometry (CWI) and digital image correlation (DIC), supported with X-ray micro-computed tomography (micro-CT) is reported. DIC and micro-CT techniques were used to characterize the fracture process in detail. CWI method was proved to be effective in the assessment of damage level based on the changes in decorrelation between coda wave signals. The possibility of early detection of damage using CWI is promising for possible applications in the diagnostics of concrete elements.
Monitoring the gas turbine start-up phase on the platform using a hierarchical model based on Multi-Layer Perceptron networks
- Tacjana Niksa-Rynkiewicz
- Anna Witkowska
- Jerzy Głuch
- Marcin Adamowicz
2022 Pełny tekst Polish Maritime Research
Very often, the operation of diagnostic systems is related to the evaluation of process functionality, where the diagnostics is carried out using reference models prepared on the basis of the process description in the nominal state. The main goal of the work is to develop a hierarchical gas turbine reference model for the estimation of start-up parameters based on multi-layer perceptron neural networks. A functional decomposition of the gas turbine start-up process was proposed, enabling a modular analysis of selected parameters of the process. Real data sets obtained from observations of the turbo-generator set located on a North Sea platform were used.
Monolithic vs. Microservice Architecture: A Performance and Scalability Evaluation
- Grzegorz Blinowski
- Anna Ojdowska
- Adam Przybyłek
2022 Pełny tekst IEEE Access
Context. Since its proclamation in 2012, microservices-based architecture has gained widespread popularity due to its advantages, such as improved availability, fault tolerance, and horizontal scalability, as well as greater software development agility. Motivation. Yet, refactoring a monolith to microservices by smaller businesses and expecting that the migration will bring benefits similar to those reported by top global companies, such as Netflix, Amazon, eBay, and Uber, might be an illusion. Indeed, for systems that do not have thousands of concurrent users and can be scaled vertically, the benefits of such migration have not been sufficiently investigated, while the existing evidence is inconsistent. Objective. The purpose of this paper is to compare the performance and scalability of monolithic and microservice architectures on a reference web application. Method. The application was implemented in four different versions, covering not only two different architectural styles (monolith vs. microservices) but also two different implementation technologies (Java vs. C#.NET). Next, we conducted a series of controlled experiments in three different deployment environments (local, Azure Spring Cloud, and Azure App Service). Findings. The key lessons learned are as follows: (1) on a single machine, a monolith performs better than its microservice-based counterpart; (2) The Java platform makes better use of powerful machines in case of computation-intensive services when compared to.NET; the technology platform effect is reversed when non-computationally intensive services are run on machines with low computational capacity; (3) vertical scaling is more cost-effective than horizontal scaling in the Azure cloud; (4) scaling out beyond a certain number of instances degrades the application performance; (5) implementation technology (either Java or C#.NET) does not have a noticeable impact on the scalability performance.
Monomeric Triphosphinoboranes: Intramolecular Lewis Acid–Base Interactions between Boron and Phosphorus Atoms
- Anna Ordyszewska
- Natalia Szynkiewicz
- Jarosław Chojnacki
- Rafał Grubba
2022 Pełny tekst INORGANIC CHEMISTRY
Herein, we present the synthesis of the first fully characterized monomeric triphosphinoboranes. The simple reaction of boron tribromide with three equivalents of bulky lithium phosphide tBu2PLi yielded triphosphinoborane (tBu2P)3B. Triphosphinoboranes with diversified phosphanyl substituents were obtained via a two-step reaction, in which isolable bromodiphosphinoborane (tBu2P)2BBr is first formed and then reacts with one equivalent of less bulky phosphide R2PLi (R2P = Cy2P, iPr2P, tBuPhP, Ph2P). By utilizing this method, we obtained a series of triphosphinoboranes with the general formula (tBu2P)2BPR2. Based on structural and theoretical studies, two main types of triphosphinoborane structures can be distinguished. In the first type, all three electron lone pairs interact with the formally empty p-orbital of the central boron atom, resulting in delocalized π-bonding, whereas in the second type, one localized double P=B bond and two single P-B bonds are observed. The Lewis acidic-basic properties of triphosphinoboranes during the reaction of (tBu2P)2BPiPr2 with H3B·SMe2 were analyzed. The abovementioned P-B bond-containing compound not only formed an adduct with BH3 but also activated the B-H bond of the borane molecule, resulting in the incorporation of the BH2 unit into two phosphorus atoms and migration of a hydride to the boron atom of the parent triphosphinoborane. The structures of the triphosphinoboranes were confirmed by single crystal X-ray analysis, multinuclear NMR spectroscopy, and elemental analysis.
More Than just Antioxidants: Redox-Active Components and Mechanisms Shaping Redox Signalling Network
- Monika Baranowska
- Patrycja Jakubek
- Agnieszka Bartoszek-Pączkowska
2022 Pełny tekst Antioxidants
settingsOrder Article Reprints This is an early access version, the complete PDF, HTML, and XML versions will be available soon. Open AccessReview More Than just Antioxidants: Redox-Active Components and Mechanisms Shaping Redox Signalling Network by Monika Kuczyńska,Patrycja Jakubek andAgnieszka Bartoszek *ORCID Faculty of Chemistry, Gdańsk University of Technology, 80-233 Gdańsk, Poland * Author to whom correspondence should be addressed. Antioxidants 2022, 11(12), 2403; https://doi.org/10.3390/antiox11122403 (registering DOI) Received: 26 September 2022 / Revised: 28 November 2022 / Accepted: 30 November 2022 / Published: 4 December 2022 (This article belongs to the Special Issue 10th Anniversary of Antioxidants—Review Collection) Download Versions Notes Abstract The concept of oxidative stress as a condition underlying a multitude of human diseases has led to immense interest in the search for antioxidant-based remedies. The simple and intuitive story of “the bad” reactive oxygen species (ROS) and “the good” antioxidants quickly (and unsurprisingly) lead to the commercial success of products tagged “beneficial to health” based solely on the presence of antioxidants. The commercial success of antioxidants by far preceded the research aimed at understanding the exact redox-related mechanisms that are in control of shaping the states of health and disease. This review describes the redox network formed by the interplay of ROS with cellular molecules and the resulting regulation of processes at the genomic and proteomic levels. Key players of this network are presented, both involved in redox signalling and control of cellular metabolism linked to most, if not all, physiological processes. In particular, this review focuses on the concept of reductive stress, which still remains less well-established compared to oxidative stress.
Morphology changes in Fe-Cr porous alloys upon high-temperature oxidation quantified by X-ray tomographic microscopy
- Damian Koszelow
- Sebastian Molin
- Jakub Karczewski
- F. Marone
- Małgorzata Makowska
2022 Pełny tekst MATERIALS & DESIGN
The effect of high-temperature oxidation at 850 C (10 h, 30 h, 100 h) and 900 C (10 h) on porous (30 % porosity) ferritic stainless steel (Fe22Cr) has been investigated using synchrotron tomographic microscopy, which allowed for visualisation, separation and quantitative analysis of the metallic core, closed pores, open pores and oxide scale phase. The same regions within the samples were investigated before and after oxidation performed at different conditions. Quantitative analysis of the tomographic data provided information on changes upon oxidation of the relative volume of the different phases, the specific surface area (SSA) of the metallic core, the thickness of the oxide scale and pore size distribution. The results were discussed in the context of thermogravimetric analysis of the samples and supported by SEM imaging. It was observed that oxidation leads to an increase of the SSA of steel and the largest increase (50 %) was obtained for the sample processed for 100 h at 850 C. It is demonstrated the open porosity forms a network of connected channels within the sample and it dominates in the volume. In addition, the 3D imaging revealed breakaway oxidation areas for samples, for which this phenomenon remained undetected using 2D SEM analysis.
MORPHOLOGY OF BUILDING DEVELOPMENT AS AN ELEMENT OF URBAN VENTIALTION SYSTEM
- Katarzyna Zielonko-Jung
- Mariya-Veronika Mochulska
2022 Pełny tekst Architecture Civil Engineering Environment
Problems related to air quality in large urban agglomerations (e.g., high concentration of pollutants, the urban heat island phenomenon) make it necessary to take comprehensive measures to improve air exchange in urban areas.The article concerns the relationship between wind phenomena observable in cities and the geometrical features of building development. The knowledge on the subject is already well-founded and has been intensively developed. Regardless, it remains relatively poorly applied to urban planning. Based on the analysis of source literature, the classification of features and spatial elements of building development that are crucial for ventilation is conducted in the following paper. Five different cities are also analyzed regardinghow the air exchange improvement policy should be pursued through conscious building development shaping. The cities selected for analysis include Warsaw and Cracow in Poland, a large agglomeration of New Dehli in India,the experimental Masdar Cityin the United Arab Emirates, and the newly designed Jätkäsaaridistrict of Helsinki. Based on the example of the above cities, the article investigates the possibilities of combining spatial features of building development that are essential to aerodynamics, in order to create effective ventilation systems.
Most Uniwersytecki w Bydgoszczy. Teoretyczne podstawy decyzji o wyłączeniu obiektu z ruchu
- Krzysztof Żółtowski
- Mikołaj Binczyk
- Przemysław Kalitowski
2022 Pełny tekst Inżynieria i Budownictwo
W artykule przedstawiono ogólny opis konstrukcji podwieszonego mostu Uniwersyteckiego nad rzeką Brdą w Bydgoszczy. Opisano również prace eksperckie dotyczące oceny nośności konstrukcji. W wyniku badań i analiz obiekt został uznany za niebezpieczny dla użytkowników i wycofany z eksploatacji. W artykule przedstawiono zasadnicze przesłanki, które doprowadziły zarządcę do podjęcia głównych decyzji i postępowania naprawczego.
MPPT and GMPPT Implementation for Buck-Boost Mode Control of quasi-Z-Source Inverter
- Oleksandr Husev
- Dmitri Vinnikov
- Carlos Roncero-Clemente
- Frede Blaabjerg
- Ryszard Strzelecki
2022 Pełny tekst IEEE TRANSACTIONS ON INDUSTRIAL ELECTRONICS
The focus is on the maximum power point tracking implementation for the buck-boost voltage mode control of a single-phase multilevel inverter based on a three-level neutral point clamped quasi-Z-source topology. To utilize shoot-through states only when boost function is needed and avoid it in the buck mode, two different control approaches are required. This work proposes merged control system which provides switching between different control algorithms in the buck and boost modes. In particular, a hysteresis band between the buck and boost modes is proposed which provides smooth and stable performance. It also includes features of the implementation of the global maximum power point tracking, which can scan the entire input voltage range in up to 10 seconds. Experimental results showed that proposed control system provides high and stable MPPT efficiency in different operation points. Finally, the key features are verified, the advantages, drawbacks, and an eventual potential for other applications are presented in conclusions.
Multiaxial Fatigue Behaviour of SLM 18Ni300 Steel
- Ricardo Branco
- José Domingos Costa
- J. A. M. Ferreira
- C. Capela
- Filippo Berto
- Wojciech Macek
2022 Structural Integrity
Fatigue behaviour of SLM 18Ni300 steel under proportional bending-torsion loading is studied. The fatigue tests are conducted under pulsating loading conditions using tubular specimens with a transversal circular hole. Three ratios of the normal stress to shear stress are considered, namely σ/τ=4,σ/τ=2 and σ/τ = 4/3. Crack initiation sites were found for two diametrically opposite points around the hole, whose locations are governed by the loading scenario. Crack angles at the early stage of growth were successfully predicted from the first principal direction at the nodes with maximum values of the first principal stress at the hole. Fatigue crack initiation life was estimated based on the SWT parameter, defined from uniaxial low-cycle fatigue tests performed for smooth standard specimens under fully reversed strain-controlled conditions. Overall, predicted lives are in agreement with the experiments.
Multi-Beam Antenna for Ka-Band CubeSat Connectivity Using 3-D Printed Lens and Antenna Array
- Kamil Trzebiatowski
- Weronika Kalista
- Mateusz Rzymowski
- Łukasz Kulas
- Krzysztof Nyka
2022 Pełny tekst IEEE Antennas and Wireless Propagation Letters
In this paper, the design of a passive multi-beam lens antenna is proposed for the CubeSat space communication system as an alternative application of a 2-D microstrip antenna array that has originally been designed for a 39 GHz 5 G MU-MIMO system. The half-ellipsoid lens is 3-D printed using stereolithography (SLA) technology. The antenna prototype is capable of selecting the main beam between 16 different directions with a gain ranging from 14 to 16 dBi and a half-power beamwidth of 14∘ to 18∘. The measurements carried out in an anechoic chamber show good agreement with numerical simulations. The presented prototype shows that by employing 3-D printing technologies existing antennas can be easily and inexpensively converted to switched-beam or multi-beam solutions.
Multi-Criterial Design of Antennas with Tolerance Analysis Using Response-Feature Predictors
- Anna Pietrenko-Dąbrowska
- Paulina Kozieł
- Leifur Leifsson
2022
Imperfect manufacturing is one of the factors affecting the performance of antenna systems. It is particularly important when design specifications are strict and leave a minimum leeway for a degradation caused by geometry or material parameter deviations from their nominal values. At the same time, conventional antenna design procedures routinely neglect to take the fabrication tolerances into account, which is mainly a result of a challenging nature of uncertainty quantification. Nevertheless, the ability to assess the effects of parameter deviations and to mitigate thereof is instrumental in achieving truly robust antenna designs. Furthermore, identifying the antenna-specific relationships be-tween nominal requirements and tolerance immunity is essential to determine the necessary levels of fabrication accuracy, which affects both the reliability and the manufacturing costs. This paper proposes a technique for multi-criterial optimization of antenna structures oriented towards rendering a family of designs rep-resenting trade-offs between the nominal performance and the robustness. The fundamental components of our procedure are feature-based regression models constructed at the level of selected characteristic points of the antenna outputs. The trade-off designs are generated sequentially, using local search carried out for gradually relaxed nominal requirements. Numerical experiments conducted for two microstrip antennas demonstrate that the proposed algorithm is capable of yielding the performance/robustness Pareto set at the cost of only a few dozens of EM analysis of the antenna at hand per design, while ensuring reliability, as validated by means of EM-based Monte Carlo simulation.
Multidirectional Characterization of Phytochemical Profile and Health-Promoting Effects of Ziziphora bungeana Juz. Extracts
- Karlygash Zhaparkulova
- Aigerim Karaubayeva
- Zuriyadda Sakipova
- Anna Biernasiuk
- Katarzyna Gaweł-Bęben
- Tomasz Laskowski
- Aliya Kusniyeva
- Azamat Omargali
- Tolkyn Bekezhanova
- Liliya Ibragimova
- Galiya Ibadullayeva
- Amangeldy Jakiyanov
- Karolina Czech
- Kuanysh Tastambek
- Kazimierz Głowniak
- Anna Malm
- Wirginia Kukula-Koch
2022 Pełny tekst MOLECULES
Ziziphora species (Lamiaceae) have been used in traditional medicine as sedatives, anti-septics, carminatives, or expectorants. Despite their common applications in phytotherapy, there is still lack of evidence about the composition of their extracts and its impact on biological properties of the plants. The aim of this study was to evaluate the content of Ziziphora bungeana, a less studied species growing in Kazakhstan, using HPLC-ESI-QTOF-MS/MS instrumentation and to determine its antimicrobial, antioxidant, and cytotoxic activity together with inhibitory properties against tyrosinase and toxicity in erythrocyte lysis assay. Extracts from Z. bungeana were found to be sources of flavonoids, phenolic acids, organic acids, and terpenes that determined their antiradical activity. The minimum inhibitory concentrations of extracts were lower for Gram-positive bacteria (1.25–10 mg/mL) than for Gram-negative bacteria and fungi (5–20 mg/mL). The EC50 value calculated for antiradical activity ranged between 15.00 ± 1.06 µg/mL and 13.21 ± 3.24 µg/mL for ABTS and DPPH assays, respectively. Z. bungeana extracts were found to decrease the activity of tyrosinase by 50% (at 200 µg/mL) similarly to kojic acid and were slightly cytotoxic for human melanoma A375 cell line (at 200 µg/mL) with no effect on HaCaT keratinocytes. In the end, Z. bungeana did not reveal toxic effects in hemolytic assay as compared to the positive control Triton X-100. The performed tests show potential application of the plant in the treatment of infectious diseases, disorders caused by free radicals, and skin problems.
Multi-domain and Context-Aware Recommendations Using Contextual Ontological User Profile
- Aleksandra Karpus
- Krzysztof Goczyła
2022
Recommender Systems (RS) became popular tools in many Web services like Netflix, Amazon, or YouTube, because they help a~user to avoid an information overload problem. One of the types of RS are Context-Aware RS (CARS) which exploit contextual information to provide more adequate recommendations. Cross-Domain RS (CDRS) were created as a response to the data sparsity problem which occurs when only few users can provide reviews or ratings for many items. One of the kinds of CDRS are Multi-domain RS which use user information from at least two domains to recommend items from all these domains. In this paper, we investigate how Contextual Ontological User Profile can be used for making multi-domain and context-aware recommendations. We show the improvement of accuracy and diversity of recommendations while combining CARS with CDRS.
Multi-functional sensor based on photonic crystal fiber using plasmonic material and magnetic fluid
- Muhammad Bilal
- Servando Lopez-Aguayo
- Małgorzata Szczerska
- Hamza Madni
2022 Pełny tekst OSA Continuum
A unique highly sensitive photonic crystal fiber is investigated based on plasmonic material and magnetic fluid (MF) for the simultaneous measurement of temperature and magnetic field sensor. The designed sensor is explored by tracing the different parameters such as birefringence, coupling length, power spectrum, and the peak wavelength of the transmission intensity. The magnetic field and temperature computation are attained simultaneously by examining the linear fitting curve and the movement of transmission peaks. The obtained sensitivity for temperature is 7.1nm/°C with an exposure range of 25°C to 100°C. In contrast, the magnetic field sensitivity is 12nm/Oe with a detection range of 160-200 Oe. In addition, the resolutions are -1.245°C, 5.53 Oe for temperature and magnetic field, respectively. Our inspected sensor is used to detect extremely low and high values of magnetic fields. The investigated structure is presented with simplification, compactness, easy implementation, and high sensitivity, which is expected to be a good foundation for the advancement of optical sensing devices in the future applications of industries, security, small grids, and environmental systems.
Multi-layered mineral glass units used as viewport elements of underwater ship structures
- Krzysztof Lipiński
- Krzysztof Bobrowski
- Edmund Wittbrodt
- Bogusław Szarejko
- Eugeniusz Ziółkowski
2022
In the paper, Authors deals with viewport elements of underwater marine constructions. If a single-plate viewport constructions are considered, big thicknesses of the glass plate are required to resist the pressure. To build the viewports from the commercially accessible glass panes, multi-layered glass units are proposed in the paper. Numerical calculations are presented, summarized and compared with experimental tests. Focusing on their main idea, proposed viewports are inspired by the classical glass-lamination, but instead of gluing them with polyvinyl butyral, the glass panes are separated with deionized water that fills up all the hermetic inter-chambers formed by the panes. Heat-tempered mineral-glass panes are considered. Significant areas of the viewports are required. Performed numerical tests are addressed to verify statics, strength and stability of the proposed multi-layered innovative construction. Finite elements are used to create the models and to calculate the stress fields of all the glass elements of the viewports. Strengths of the investigated multi-layered units are estimated according to probabilistic theory of failure. Different constructional variants are tested for the viewports, including these made of flat and of curved glass panes. The final parameters of the optimal solution are not presented in the paper. The paper-presented examples certify however, that significant reduction of stresses is possible, especially of these occurring in the glass panes and, what follows, it certify that construction of underwater viewports of considerable dimensions is possible for viewports based on the standard thicknesses of the commercially accessible glass panes.
Multipath Complex Root Tracing
- Sebastian Dziedziewicz
- Małgorzata Warecka
- Rafał Lech
- Piotr Kowalczyk
2022
The problem of multipath root tracing is being addressed in this communication. The self-adaptive complex root tracing algorithm, which was previously utilized for the investigation of various propagation and radiation problems, is analyzed here for the cases when the traced characteristic bifurcates. A procedure of multiroute detection is proposed and demonstrated on the coaxially loaded cylindrical waveguide example.
Multi-pathway mechanism of polydopamine film formation at vertically aligned diamondised boron-doped carbon nanowalls
- Adrian Olejnik
- Mateusz Ficek
- Katarzyna Siuzdak
- Robert Bogdanowicz
2022 ELECTROCHIMICA ACTA
Boron-doped carbon nanowall (B:CNW) electrodes were used as a platform for studying the electropolymerisation of dopamine. Due to the unique properties of B:CNW, including the fast charge-transfer kinetics and high surface conductivity, a high degree of reversibility of redox reactions was achieved. Three separated redox peaks were observed on voltammograms and attributed to three fundamental reactions in the dopamine polymerisation mechanism: dopamine/dopamine quinone, leukodopaminechrome/dopaminechrome, and dihydroxyindole/indolequinone. The mechanism was also supported by the density functional theory calculations of the single point energy of the polydopamine structural units. Moreover, the electrochemical impedance spectroscopy experiments strongly suggest that the majority of th epolymerisation occurs only in the narrow range of potentials between +0.0 and +0.4 V vs. the silver chloride reference electrode. The concept of a resistor-like CPE element is introduced to facilitate the description of the electrochemical properties of B:CNW electrodes in a neutral electrolyte. Further, it is shown that electropolymerisation differs significantly as a function of pH. In acidic environments (pH 3–6) mostly the dopamine/dopamine quinone reaction can be seen, whereas in a more alkaline pH (8–10), the leukodopaminechrome/dopaminechrome reaction becomes dominant. The dihydroxyindole/indolequinone redox pair is seen only in a short pH interval between 7 and 8. Additionally, the kinetics of polymerisation is significantly boosted when the pH is more than 7. Together, these results provide insight into the complexity of the formation of polydopamine and can assist in better controlling the properties of electropolymerised dopamine films.
Multiple Cues-Based Robust Visual Object Tracking Method
- Baber Khan
- Abdul Jalil
- Ahmad Ali
- Khaled Alkhaledi
- Khizer Mehmood
- Khalid Mehmood Cheema
- Maria Murad
- Hanan Tariq
- Ahmed M. El-Sherbeeny
2022 Pełny tekst Electronics
Visual object tracking is still considered a challenging task in computer vision research society. The object of interest undergoes significant appearance changes because of illumination variation, deformation, motion blur, background clutter, and occlusion. Kernelized correlation filter- (KCF) based tracking schemes have shown good performance in recent years. The accuracy and robustness of these trackers can be further enhanced by incorporating multiple cues from the response map. Response map computation is the complementary step in KCF-based tracking schemes, and it contains a bundle of information. The majority of the tracking methods based on KCF estimate the target location by fetching a single cue-like peak correlation value from the response map. This paper proposes to mine the response map in-depth to fetch multiple cues about the target model. Furthermore, a new criterion based on the hybridization of multiple cues i.e., average peak correlation energy (APCE) and confidence of squared response map (CSRM), is presented to enhance the tracking efficiency. We update the following tracking modules based on hybridized criterion: (i) occlusion detection, (ii) adaptive learning rate adjustment, (iii) drift handling using adaptive learning rate, (iv) handling, and (v) scale estimation. We integrate all these modules to propose a new tracking scheme. The proposed tracker is evaluated on challenging videos selected from three standard datasets, i.e., OTB-50, OTB-100, and TC-128. A comparison of the proposed tracking scheme with other state-of-the-art methods is also presented in this paper. Our method improved considerably by achieving a center location error of 16.06, distance precision of 0.889, and overlap success rate of 0.824.
Multiple jets impingement – numerical analysis by the ζ-f and hybrid VLES turbulence models
- Tomasz Kura
- Elżbieta Fornalik-Wajs
- Jan Wajs
- Sasa Kenjeres
2022
Presented paper summarizes the Authors findings referring to the numerical analyses of the jet impinging phenomena in the case of complex jets configurations in various applications e.g. in the heat exchangers. Multiple jets interference resulting in the cross-flow and the surface curvature are the factors which impose the need of advanced turbulence models utilization. The outcome of the research based on the ζ-f turbulence model as the common part in the RANS and the hybrid VLES formulations, is discussed. The advantage of the VLES model in the analysis of the complex interaction between the impinging jets has been demonstrated.