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Gdańsk University of Technology

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  • Real-time monitoring of volatiles and particles emitted from thermoplastic filaments during 3D printing
    • Wojciech Wojnowski
    2021

    Presentation on the use of instrumental analytical techniques for the assessment of emission of volatiles and particulates during fdm 3d printing.

  • Recent Advances in Accelerated Multi-Objective Design of High-Frequency Structures using Knowledge-Based Constrained Modeling Approach
    • Sławomir Kozieł
    • Anna Pietrenko-Dąbrowska
    2021 KNOWLEDGE-BASED SYSTEMS

    Design automation, including reliable optimization of engineering systems, is of paramount importance for both academia and industry. This includes the design of high-frequency structures (antennas, microwave circuits, integrated photonic components), where the appropriate adjustment of geometry and material parameters is crucial to meet stringent performance requirements dictated by practical applications. Realistic design has to account for multiple objectives, which are often conflicting. Identification of available trade-offs (e.g., electrical/field properties vs. physical size and cost), otherwise essential from industry standpoint, requires multi-objective optimization. It is a computationally expensive endeavor as in most cases—for the sake of accuracy—the system evaluation has to be carried out using full-wave electromagnetic (EM) analysis. Attempting to solve EM-driven multi-objective (MO) tasks directly using population-based nature-inspired techniques may be prohibitive in terms of cost. Employing surrogate modeling techniques can lead to mitigation of the cost issue; however, construction of fast replacement models over broad ranges of the system parameters is expensive by itself, especially in higher-dimensional spaces. Recently, several approaches involving knowledge-based surrogate modeling approach have been proposed with the metamodels constructed over small regions of the parameter space containing the Pareto front. The latter are approximated using the sets of pre-optimized reference designs and permit a dramatic reduction of the number of training points required to set up a reliable surrogate, thus reducing the overall cost of the MO process. This paper reviews the recent advancements in these methodologies, and demonstrates the benefits of domain confinement using the various techniques such as reference design triangulation, nested kriging, and modeling with explicit dimensionality reduction using spectral analysis of the reference set. Demonstration examples of multi-objective design of antenna and miniaturized microwave components are provided as well.

  • Recent Advances in Loop Heat Pipes with Flat Evaporator
    • Paweł Szymański
    • Richard Law
    • Ryan McGlen
    • David Reay
    2021 Full text ENTROPY

    The focus of this review is to present the current advances in Loop Heat Pipes (LHP) with flat evaporators, which address the current challenges to the wide implementation of the technology. A recent advance in LHP is the design of flat-shaped evaporators, which is better suited to the geometry of discretely mounted electronics components (microprocessors) and therefore negate the need for an additional transfer surface (saddle) between component and evaporator. However, various challenges exist in the implementation of flat-evaporator, including (1) deformation of the evaporator due to high internal pressure and uneven stress distribution in the non-circular casing; (2) heat leak from evaporator heating zone and sidewall into the compensation chamber; (3) poor performance at start-up; (4) reverse flow through the wick; or (5) difficulties in sealing, and hence frequent leakage. This paper presents and reviews state-of-the-art LHP technologies; this includes an (a) review of novel manufacturing methods; (b) LHP evaporator designs; (c) working fluids; and (d) construction materials. The work presents solutions that are used to develop or improve the LHP construction, overall thermal performance, heat transfer distance, start-up time (especially at low heat loads), manufacturing cost, weight, possibilities of miniaturization and how they affect the solution on the above-presented problems and challenges in flat shape LHP development to take advantage in the passive cooling systems for electronic devices in multiple applications.

  • Recent advances on spinel-based protective coatings for solid oxide cell metallic interconnects produced by electrophoretic deposition
    • E Zanchi
    • A Sabato
    • Sebastian Molin
    • Grzegorz Cempura
    • A Boccaccini
    • F Smeacetto
    2021 MATERIALS LETTERS

    The application of ceramic protective coatings to the metallic interconnects in solid oxide cells (SOCs) is a viable and effective method to limit interconnect degradation issues. This featured letter provides a critical overview of the main outcomes of current research on the use of the electrophoretic deposition (EPD) technique to produce protective coatings for SOC metallic interconnects, specifically focusing on different approaches to stabilise spinel-based suspensions, as well as the possible sintering procedures. The protective properties of EPD coatings are reviewed and discussed in terms of oxidation kinetics and area specific resistance evaluation.

  • Recent advances on the removal of phosphorus in aquatic plant-based systems
    • Shahabaldin Rezania
    • Hesam Kamyab
    • Parveen Fatemeh Rupani
    • Junboum Park
    • Nicole Nawrot
    • Ewa Wojciechowska
    • Krishna Kumar Yadav
    • Majid Lotfi Ghahroud
    • Ali Akbar Mohammadi
    • Sathiabama T. Thirugnana
    • Shreeshivadasan Chelliapan
    • Marina M.S. Cabral-Pinto
    2021 Environmental Technology & Innovation

    Phosphorus (P) is a vital nutrient for the ecosystems and its excess in wastewater streams leads to some environmental issues such as extensive algae growth (eutrophication). Phytoremediation is a green technology that is based on the combined actions of plants and their associated microbial groups to remove and transfer the toxic compounds in surface water, groundwater and soil. Aquatic plants are widely used for the remediation of contaminated rivers, eutrophic lakes, and other water bodies. In the past three decades, free-floating, submerged, emergent macrophytes and microalgae species have been used for P removal in aquatic plant-based systems such as constructed wetlands (CWs). This paper reviews the recent studies on the potential of aquatic plants such as free-floating, submerged, and emergent plants, and also microalgae for removal of P in different types of wastewaters. Several parameters such as plant species, hydraulic retention time, temperature, type of CWs, effluent concentration, and seasonal changes have effects on P removal. Based on the findings, some of the species such as Azolla and water hyacinth had the highest uptake ability up to 90% while algae species such as Chlorella showed about 70% of P removal. In addition, the mixed culture of aquatic plants can increase P removal if the interaction of the species is considered before cultivation in CWs.

  • Recent Applications of 1D GC-MS and 2D GC-MS in Foodomics Studies
    • Tomasz Majchrzak
    • Kaja Kalinowska
    • Martyna Lubinska-Szczygeł
    • Anna Różańska
    • Tomasz Dymerski
    • Waldemar Wardencki
    • Jacek Namieśnik
    2021

    Gas chromatography coupled with mass spectrometry and food chemistry have been tightly linked since the 1960s. This setup is also an integral part of the omics studies when it comes to low mass metabolites. Therefore, the marriage of GC-MS and foodomics is obvious. Two-dimensional gas chromatography coupled with mass spectrometry fits perfectly within the latest trends in foodomics, since it is tailored for holistic food analysis. In this article, the authors will focus on the current trends in 1D and 2D GC-MS-based foodomics.

  • Recent Developments in Data-Assisted Modeling of Flexible Proteins
    • Cezary Czaplewski
    • Zhou Gong
    • Emilia Lubecka
    • Kai Xue
    • Chun Tang
    • Adam Liwo
    2021 Full text Frontiers in Molecular Biosciences

    Many proteins can fold into well-defined conformations. However, intrinsically-disordered proteins (IDPs) do not possess a defined structure. Moreover, folded multi-domain proteins often digress into alternative conformations. Collectively, the conformational dynamics enables these proteins to fulfill specific functions. Thus, most experimental observables are averaged over the conformations that constitute an ensemble. In this article, we review the recent developments in the concept and methods for the determination of the dynamic structures of flexible peptides and proteins. In particular, we describe ways to extract information from nuclear magnetic resonance small-angle X-ray scattering (SAXS), and chemical cross-linking coupled with mass spectroscopy (XL-MS) measurements. All these techniques can be used to obtain ensemble-averaged restraints or to re-weight the simulated conformational ensembles.

  • Recovering Evaluation of Narrow-Kerf Teeth of Mini Sash Gang Saws
    • Kazimierz Orłowski
    • Daniel Chuchała
    • Tomasz Przybyliński
    • Stanisław Legutko
    2021 Full text Materials

    Sash gang saws with narrow-kerf saw blades are used in the production of glued laminate flooring elements in plants where dry technology is applied. This means that boards or friezes are sawn into top layer lamellae in dry conditions (moisture content of about 10–12%) from expensive wood species, often exotic. The object of this research was stellite-tipped teeth of narrow kerf saw blades sharpened under industrial conditions. A NIKON ECLIPSE Ti-S microscope equipped with a NIKON DS-Fi2 recording camera was used to take pictures of teeth, which were analysed in a graphical software to measure the radii of the main cutting edges. The high-quality images obtained were used to determine the values of the rounding radii of the cutting edges. It was noted that the quality of edges regenerated in industrial conditions, some of which had chipping, was lower than that of brand new saw blades.

  • Recovery of Valuable Materials and Methods for Their Management When Recycling Thin-Film CdTe Photovoltaic Modules
    • Anna Kuczyńska-Łażewska
    • Ewa Klugmann-Radziemska
    • Agnieszka Witkowska
    2021 Full text Materials

    Due to the development of new photovoltaic technologies, there is a need to research new recycling methods for these new materials. The recovery of metals from photovoltaic (PV) modules would reduce the consumption of raw materials. Therefore, the development of recycling technologies for used and damaged modules of newer generations is important for environmental reasons. The aim of the research is to shed light on the nature of the chemical reactions that occur in recycling technology for second-generation photovoltaic modules. This work is focused mainly on cells made of Cadmium Telluride (CdTe). It was proven that prior thermal delamination was necessary. Moreover, an improvement in understanding of the recovery process depending on used leaching solution was achieved.

  • Recycling of Polyurethanes Containing Flame-Retardants and Polymer Waste Transformed into Flame-Retarded Polyurethanes
    • Marcin Włoch
    2021

    The growing number of polyurethanes (PUs) produced every year has developed methods for their mechanical and chemical recycling which yield valuable products like substitutes for commercial polyols or flame-retardants. PUs can be produced in different shapes and forms (i.e., elastomers, flexible or rigid foams, coatings, etc.) using several different components (i.e., di- or polyisocyanates, ester- or ether-based polyols, low-molecular weight chain extenders, fillers, and other modifiers). Therefore, different recycling methods should be considered for a wide range of materials, including postproduction of postconsumer wastes) depending on their chemical structure and properties. This chapter presents a review of selected mechanical (e.g., regrinding and using as a filler, rebonding, and compression molding) and chemical (e.g., glycolysis, glycerolysis, acidolysis and phosphorolysis) recycling methods applicable for PUs. This chapter also presents examples of flame-retardants and flame-retarded PUs obtained by PU recycling, poly(ethylene terephthalate), and melamine formaldehyde foam.

  • Recycling of Waste Rubber by the Manufacturing of Foamed Polyurethane-Based Composites—Current State and Perspectives
    • Aleksander Hejna
    • Krzysztof Formela
    • Łukasz Zedler
    • Paulina Kosmela
    • Adam Olszewski
    2021 Full text Proceedings

    Worn car tires are disruptive waste, and the issue of their management is crucial for the natural environment. In many countries, the primary method of end-of-life tires utilization is energy recovery. However, more effective and beneficial for the environment is material recycling. Using them for the production of polymer-rubber composites seems to be an auspicious direction of research. Incorporation of ground tire rubber into polyurethane matrix should be considered as a method of waste rubber utilization. Moreover, it could significantly reduce the use of petroleum-based polyols and isocyanates, which are commonly considered as toxic chemicals. Therefore, the total impact on the environment could be noticeably reduced, which should be considered as very beneficial step towards more “green” polymer composites. This work aims to summarize the literature reports related to the foamed polyurethane/ground tire rubber composites. It particularly emphasizes the need for compatibilization of these materials by the enhancement of interfacial interactions between the polyurethane matrix and rubber filler phase, which significantly affect the performance properties of prepared materials. As an example, we presented our research results. Besides, future trends and limitations related to this type of composite materials are underlined.

  • Recycling of Waste Rubber by Thermo-Mechanical Treatment in a Twin-Screw Extruder
    • Łukasz Zedler
    • Paulina Kosmela
    • Adam Olszewski
    • Paulina Burger
    • Krzysztof Formela
    • Aleksander Hejna
    2021 Full text Proceedings

    Recycling of waste tires is a significant issue considering both environmental and economic aspects. One of the leading recycling routes is the shredding of tires resulting in the generation of ground tire rubber. This material can be easily introduced into various polymer matrices as a filler, reducing the use of conventionally applied petroleum-based materials. In such cases, it is essential to ensure sufficient interfacial compatibility, which could be achieved by the proper modification of the rubber surface. Different methods of treatment of ground tire rubber aim to activate its surface and introduce functional groups, which could provide the possibility for interfacial interactions and incorporation of the significant amounts of recycled material. Therefore, in the presented paper, we examined the impact of thermo-mechanical treatment in twin-screw extruder on the appearance and chemical structure of ground tire rubber. Moreover, for each set of process parameters, the specific mechanical energy required for the processing was calculated, which could provide essential insights for the potential industrial application of the analyzed process. The energy demand should be considered as a very important issue during development of “greener” processes and materials.

  • Redox property switching in MOFs with open metal sites for improved catalytic hydrogenation performance
    • Longlong Geng
    • Wenfeng Zhou
    • Xiaoli Wang
    • Tingting Li
    • Andrzej Nowak
    • Zhongmin Liu
    • Yong-Zheng Zhang
    • Da-Shuai Zhang
    • Xiuling Zhang
    • Haixiang Han
    2021 JOURNAL OF ALLOYS AND COMPOUNDS

    In this study, a decompression-thermalization strategy was utilized for a Cu-containing metal-organic framework (MOF) to tune its redox and catalytic hydrogenation properties. Remarkably, at just 120 °C, open metal sites (OMSs) were successfully constructed by removing coordinated solvent molecules to generate the daughter MOF-120. The tailored redox property of MOF-120 is correlated with the presence of OMSs. Compared with the pristine MOF where copper cations were capped by DMF, MOF-120 exhibited improved kinetics, showed a reduction of activation energy and outstanding recyclability in the hydrogenation of 4-nitrophenol under mild conditions (25 °C, 1 atm). Both experimental studies and theoretical calculation results reveal that the generation of OMSs endows the Cu species with unique electronic properties, which assist the adsorption and electron transfer between substrate molecules and is responsible for the enhanced performance in the hydrogenation process.

  • Reduced-Cost Microwave Design Closure by Multi-Resolution EM Simulations and Knowledge-Based Model Management
    • Sławomir Kozieł
    • Anna Pietrenko-Dąbrowska
    • Piotr Płotka
    2021 Full text IEEE Access

    Parameter adjustment through numerical optimization has become a commonplace of contemporary microwave engineering. Although circuit theory methods are ubiquitous in the development of microwave components, the initial designs obtained with such tools have to be further tuned to improve the system performance. This is particularly pertinent to miniaturized structures, where the cross-coupling effects cannot be adequately accounted for using equivalent networks. For the sake of reliability, design closure is normally performed using full-wave electromagnetic (EM) simulation models, which entails considerable computational expenses, often impractically excessive. Available mitigation techniques include acceleration of the conventional (e.g., gradient-based) routines using adjoint sensitivities or sparse sensitivity updates, surrogate-assisted and machine learning algorithms, the latter often combined with nature-inspired procedures. Another alternative is the employment of variable-fidelity simulations (e.g., space mapping, co-kriging), which is most often limited to two levels of accuracy (coarse/fine). This work discusses an EM model management approach coupled with trust-region gradient-based routine, which exploits problem-specific knowledge for continuous (multi-level) modification of the discretization density of the microwave structure at hand in the course of the optimization run. The optimization process is launched at the lowest discretization level, thereby allowing for low-cost exploitation of the knowledge about the device under study. Subsequently, based on the convergence indicators, the model fidelity is gradually increased to ensure reliability. The simulation fidelity selection is governed by the algorithm convergence indicators. Computational speedup is achieved by maintaining low resolution in the initial stages of the optimization run, whereas design quality is secured by eventually switching to the high-fidelity model when close to concluding the process. Numerical verification is carried out using two microstrip circuits, a dual-band power divider and a dual-band branch-line coupler, with the average savings of almost sixty percent when compared to single-fidelity optimization.

  • Regularized identification of fast time-varying systems - comparison of two regularization strategies
    • Artur Gańcza
    • Maciej Niedźwiecki
    2021 Full text

    The problem of identification of a time-varying FIR system is considered and solved using the local basis function approach. It is shown that the estimation (tracking) results can be improved by means of regularization. Two variants of regularization are proposed and compared: the classical L2 (ridge) regularization and a new, reweighted L2 one. It is shown that the new approach can outperform the classical one and is computationally attractive.

  • Regularized Identification of Time-Varying FIR Systems Based on Generalized Cross-Validation
    • Artur Gańcza
    • Maciej Niedźwiecki
    2021 Full text

    A new regularization method is proposed and applied to identification of time-varying finite impulse response systems. We show, that by a careful design of the regularization constraint, one can improve estimation results, especially in the presence of strong measurement noise. We also show that the the most appropriate regularization gain can be found by direct optimization of the generalized cross-validation criterion.

  • Regularized Local Basis Function Approach to Identification of Nonstationary Processes
    • Artur Gańcza
    • Maciej Niedźwiecki
    • Marcin Ciołek
    2021 Full text IEEE TRANSACTIONS ON SIGNAL PROCESSING

    The problem of identification of nonstationary stochastic processes (systems or signals) is considered and a new class of identification algorithms, combining the basis functions approach with local estimation technique, is described. Unlike the classical basis function estimation schemes, the proposed regularized local basis function estimators are not used to obtain interval approximations of the parameter trajectory, but provide a sequence of point estimates corresponding to consecutive instants of time. Based on the results of theoretical analysis, the paper addresses and solves all major problems associated with implementation of the new class of estimators, such as optimization of the regularization matrix, adaptive selection of the number of basis functions and the width of the local analysis interval, and reduction of complexity of the computational algorithms.

  • Reinforcement Learning Algorithm and FDTD-based Simulation Applied to Schroeder Diffuser Design Optimization
    • Adam Kurowski
    • Bożena Kostek
    2021 Full text IEEE Access

    The aim of this paper is to propose a novel approach to the algorithmic design of Schroeder acoustic diffusers employing a deep learning optimization algorithm and a fitness function based on a computer simulation of the propagation of acoustic waves. The deep learning method employed for the research is a deep policy gradient algorithm. It is used as a tool for carrying out a sequential optimization process the goal of which is to maximize the fitness function based on parameters characterizing the autocorrelation diffusion coefficient of the designed acoustic diffuser. As the autocorrelation acoustic diffusion coefficients are calculated from the polar response of a diffuser, the FDTD (finite-difference time-domain) simulation method is used to obtain a set of impulse responses necessary to calculate the polar responses of the optimized Schroeder diffusers. The results obtained from optimization based on the deep learning algorithm were compared with the outcomes of an analogous algorithm employing a genetic algorithm, and based on random selection of the Schroeder diffuser well depth pattern. We found that the best result was achieved by the deep policy gradient, as it produced outcomes, which, in terms of the provided autocorrelation diffusion coefficient, were statistically better than properties of designs provided by two other baseline approaches.

  • Relacja mistrz – uczeń – w jaki sposób kształtować doskonałość akademicką, na przykładzie postaci prof. dr. hab. inż. Romualda Kolmana
    • Piotr Grudowski
    • Małgorzata Wiśniewska
    2021 Problemy Jakości

    W niniejszym artykule skoncentrowano się na zagadnieniu fundamentalnym w kontekście edukacji i rozwoju badań naukowych – relacji mistrz – uczeń. W nawiązaniu do wielowiekowej tradycji instytucji akademickich przedstawiono istotę i znaczenie tych relacji, wskazując pożądane cechy mistrza jako osoby kształtującej oczekiwane ze względów społecznych postawy swoich podopiecznych. Jako przykład postaci mistrza w obszarze nauk o jakości zaprezentowano sylwetkę śp. Profesora Romualda Kolmana oraz wspomnienia niektórych z jego wychowanków. W nawiązaniu do obecnej sytuacji w systemie szkolnictwa wyższego i nauki w Polsce autorzy pragną w ten sposób zwrócić uwagę na – ich zdaniem – zdecydowanie niewystarczające, a wręcz pomijane w różnego rodzaju regulacjach, wsparcie tej sfery aktywności akademickiej

  • Relating Information Culture to Information Policies and Management Strategies
    • Denise A. D. Bedford
    • Wioleta Kucharska
    2021

    Business and information managers have struggled to meet several challenges in aligning information strategies and business cultures. The consequences of a misalignment or misfit of strategy and culture are well known in business literature, and better guidance on how to better align strategy and culture is needed. This means expanding the puzzle to align business and information cultures, align business and information strategies, and ensuring that there is a good ongoing fit between information cultures and business strategies. It also means that awareness of the information capabilities of an organization needs to be raised along with the different levels and types of information cultures. Relating Information Culture to Information Policies and Management Strategies is a critical scholarly publication that provides a holistic picture of information cultures in order to help business managers understand those cultures and to provide a foundation upon which to ground and grow future information culture research. Highlighting a wide range of topics such as information culture, business strategies, and risk assessment, this book is essential for business managers, organizational executives, information managers, cultural experts, practitioners, academicians, managers, researchers, and students.

  • Relationships Between Geographical and Virtual Proximity in Cluster Organisations
    • Anna Lis
    • Adrian Lis
    2021 Full text Studia Regionalne i Lokalne

    The purpose of the paper is to explore the relationships between geographical and virtual proximity in cluster organizations (COs). The authors report the findings of a qualitative study conducted in four COs in Poland. The basic technique for collecting and analyzing data was an in-depth individual interview and qualitative content analysis. The research has shown that the relationships between geographical and virtual proximity depends on the cooperation level and the role of the CO. The findings presents a broader view on cluster cooperation as a phenomenon based in geographical proximity which facilitates personal interactions, but supported by various ICT tools.

  • Relative Productivity, Country Size and Export Diversification
    • Andrzej Cieślik
    • Aleksandra Parteka
    2021 Full text Structural Change and Economic Dynamics

    This paper analyses the effects of productivity and country size on the extent of trade structure diversification. Using a testable version of the Ricardian model, we show that relative export variety is an outcome of two forces: a relative productivity change (technological progress) and a relative country size change (labour force growth). The model predictions are validated empirically using product-level trade data for a sample of 132 countries (1988–2014), including 53 low-income countries. We find a robust positive relationship between export variety and the countries’ relative productivity, as well as a negative relationship between export variety and the expansion of foreign economies (i.e., the growth of the RoW). The effect of technology differences on export variety is driving diversification especially at the beginning of the development process. The results are robust to changes in the measurement of export variety (also in terms of economic complexity), in the set of control variables, or in the estimation methods.

  • Relay-aided Wireless Sensor Network Discovery Algorithm for Dense Industrial IoT utilizing ESPAR Antennas
    • Fjolla Ademaj
    • Mateusz Rzymowski
    • Hans-Peter Bernhard
    • Krzysztof Nyka
    • Łukasz Kulas
    2021 Full text IEEE Internet of Things Journal

    Industrial Internet of Things (IIoT) applicationsrequire reliable and efficient wireless communication. Assumingdense Wireless Sensor Networks (WSNs) operating in a harshenvironment, a concept of a Time Division Multiple Access(TDMA) based WSN enriched with Electronically SteerableParasitic Array Radiator (ESPAR) antennas is proposed andexamined in this work. The utilized antenna provides oneomnidirectional and 12 directional radiation patterns that can beelectronically switched by the sensor node. We introduce a relaydiscovery algorithm which selects those sensor nodes with anESPAR antenna capable to act as relay. The selection of the relaynodes is based on a certain link quality threshold that algorithmuses as input. The outcome is a reduction in number of layers orhops with a guaranteed Quality of Service (QoS). To emphasizethe physical aspect of the wireless propagation, we introduce themeasured antenna radiation patterns and consider two differentpath loss propagation models representing blockage-free andblockage-prone industrial environments. A number of networksimulations were performed and Signal-to-Noise Ratio (SNR) as alink quality measure was examined with respect to the networkdensity and different measured radiation pattern settings. Themain outcomes show a trade-off between SNR per link and thepercentage of nodes that can serve as relays. As a result, wepropose network design guidelines that take under considerationthe QoS range with respect to SNR together with an optimalnumber of antenna radiation patterns that should be selected asa trade-off between latency, energy consumption and reliabilityin a network

  • Release Kinetics Studies of Early-Stage Volatile Secondary Oxidation Products of Rapeseed Oil Emitted during the Deep-Frying Process
    • Tomasz Majchrzak
    • Andrzej Wasik
    2021 Full text MOLECULES

    The research concerns the use of proton transfer reaction mass spectrometer to track real-time emissions of volatile secondary oxidation products released from rapeseed oil as a result of deep-frying of potato cubes. Therefore, it was possible to observe a sudden increase of volatile organic compound (VOC) emissions caused by immersion of the food, accompanied by a sudden release of steam from a potato cube and a decrease of the oil temperature by more than 20 °C. It was possible to identify and monitor the emission of major secondary oxidation products such as saturated and unsaturated aldehydes, namely acrolein, pentanal, 2-hexenal, hexanal, 2-nonenal and 2-decenal. Each of them has an individual release characteristic. Moreover, the impact of different initial frying temperatures on release kinetics was investigated. Subsequently, it was possible to approximate the cumulative emission by a second-degree polynomial (R2 ≥ 0.994). Using the proposed solution made it possible for the first time to observe the impact of the immersion of food in vegetable oil on the early emission of thermal degradation products oil.

  • Remarkable visible-light induced hydrogen generation with ZnIn2S4 microspheres/CuInS2 quantum dots photocatalytic system
    • Onur Cavdar
    • Anna Malankowska
    • Daniel Amgar
    • Paweł Mazierski
    • Justyna Łuczak
    • Wojciech Lisowski
    • Adriana Zaleska-Medynska
    2021 Full text INTERNATIONAL JOURNAL OF HYDROGEN ENERGY

    A new and active material in the form of ZnIn2S4 microspheres decorated by CuInS2 quantum dots have been obtained by hydrothermal method for the first time. The optimum amount of CuInS2 quantum dots (1.13 wt.%) introduced into rection medium during ZnIn2S4 microspheres synthesis increased the photocatalytic H2 generation rate by 2.5 times than that of bare ZnIn2S4 photocatalysis under visible light irradiation. This sample exhibited strong photoactivity in the extended visible range up to 540 nm with 30.6% apparent quantum efficiency (λ = 420 nm).

  • Remote command and control capabilities for data acquisition systems provided by delay-tolerant network mechanisms
    • Michał Hoeft
    • Krzysztof Gierłowski
    • Marcin Wichorowski
    2021 Bollettino di Geofisica Teorica ed Applicata

    The paper presents an assessment of a remote device reconfiguration service employing a Delay Tolerant Network (DTN) mechanisms. This service has been implemented as a part of a communication appliance dedicated to marine data transfer in off-shore and open sea areas. The service has been successfully deployed and validation test have been completed. The practical use-case has been defined as remote access to the equipment operating onboard RV “Oceania” during cruise on Southern Baltic Area. A summary of service characteristics is included, as well as simulation results of large scale deployment of the system in the south and central areas of Baltic Sea.

  • Remote communication in Scrum teams - a COVID-19 preventive measure or work time optimisation?
    • Kamil Brodnicki
    2021 Full text e-mentor

    The article presents the impact of remote work, resulting from the COVID-19 pandemic, on the functioning of Scrum teams. Attempts have been made to analyse the positive and negative aspects of remote work. The article also looks at the impact of remote work on the level of communication and efficiency of Scrum teams. For this purpose, the author conducted research on a sample of 40 organisations that declared to use Scrum methodology, using 187 questionnaires as the research material. The study was carried out at the turn of April and May 2021 and was carried out using the CAWI technique. The obtained results were analysed using the Principal Component Analysis and Cluster Analysis methods, and enable defining a picture of an organisation's readiness to work remotely. In addition, they also allowed for an assessment of how the infrastructure used for remote work communication translates into the organisation of Sprint meetings. This paper presents conclusions aimed at counteracting the observed irregularities detected during the tests. At the end, the author proposes solutions that could improve communication within Scrum teams, with remote work in mind.

  • Remote measurement of building usable floor area - Algorithms fusion
    • Artur Janowski
    • Małgorzata Renigier-Biłozor
    • Marek Walacik
    • Aneta Chmielewska
    2021 LAND USE POLICY

    Rapid changes that are taking place in the urban environment have significant impact on urban growth. Most cities and urban regions all over the world compete to increase resident and visitor satisfaction. The growing requirements and rapidity of introducing new technologies to all aspects of residents' lives force cities and urban regions to implement "smart cities" concepts in their activities. Real estate is one of the principal anthropogenic components of urban environment thus become a subject of thorough multidisciplinary analysis in the field of data requiring spatial information systems. Recent advances in information technology, combined with the increased availability of high-resolution imagery from Earth observation, create an opportunity to use new sources of data that enable to identify, monitor, and solved many of urban environmental problem. The aim of the paper is to elaborate precise, complete and detailed property information with the use of remote sensing observations in a suitable numerical algorithm. The authors concentrate on providing one of the most important, and probably the most lacking, feature describing properties - building usable floor area (BUFA). The solution is elaborated in the form of an automatic algorithm based on machine learning and computer vision technology related to LiDAR (big data), close range images with respect to spatial information systems requirements. The obtained results related to BUFA estimation in comparison to the state-of-the-art results are satisfactory and may increase the reliability of decision-making in investment, fiscal, registration and planning aspects.

  • Removal efficiency of phenol by ozonation process with calcium peroxide from aqueous solutions
    • Zhila Honarmandrad
    • Neda Javid
    • Mohammad Malakootian
    2021 Full text Applied Water Science

    Phenol has been introduced as a priority pollutant by the US Environmental Protection Agency. Advanced oxidation processes (AOPs) are one of the most efcient methods for removal of non-degradable organic pollutants in aqueous solutions. The removal efciencies of phenol and COD under optimal conditions pH=3, phenol concentration=5 mg/L, CaO2 concentration=0.025 mg/L, temperature 25 °C, 1 g/min ozonation rate and contact time=90 min in synthetic and real samples (Zarand coal washing factory in Kerman) were obtained 97.8%, 87% and 80%, 65.4%, respectively. The kinetics of phenol decomposition follows from the pseudo-frst-order equation. Thermodynamic studies show that phenol decomposition with ozonation and calcium peroxide is an endothermic process. The use of ozonation process with calcium peroxide is an efcient method and can be recommended as a coefcient method for the removal of phenol.

  • Removal of cyclohexane and ethanol from air in biotrickling filters inoculated with Candida albicans and Candida subhashii
    • Piotr Rybarczyk
    • Milena Marycz
    • Bartosz Szulczyński
    • Anna Brillowska-Dąbrowska
    • Agnieszka Rybarczyk
    • Jacek Gębicki
    2021 Full text Archives of Environmental Protection

    This paper presents investigations on the removal of cyclohexane and ethanol from air in polyurethane- -packed biotrickling filters, inoculated with Candida albicans and Candida subhashii fungal species. Results on process performance together with flow cytometry analyses of the biofilm formed over packing elements are presented and discussed. The results indicate that the presence of ethanol enhances the removal efficiency of cyclohexane from air. This synergistic effect may be attributed to both co-metabolism of cyclohexane with ethanol as well as increased sorption efficiency of cyclohexane to mineral salt medium in the presence of ethanol. Maximum elimination capacities of 89 g m-3 h-1 and 36.7 g m-3 h-1 were noted for cyclohexane and ethanol, respectively, when a mixture of these compounds was treated in a biofilter inoculated with C. subhashii. Results of flow cytometry analyses after 100 days of biofiltration revealed that about 91% and 88% of cells in biofilm remained actively dividing, respectively for C. albicans and C. subhashii species, indicating their good condition and ability to utilize cyclohexane and ethanol as a carbon source.

  • Removal of Siloxanes from Model Biogas by Means of Deep Eutectic Solvents in Absorption Process
    • Edyta Słupek
    • Patrycja Makoś-Chełstowska
    • Jacek Gębicki
    2021 Full text Materials

    The paper presents the screening of 20 deep eutectic solvents (DESs) composed of tetrapropylammonium bromide (TPABr) and glycols in various molar ratios, and 6 conventional solvents as absorbents for removal of siloxanes from model biogas stream. The screening was achieved using the conductor-like screening model for real solvents (COSMO-RS) based on the comparison of siloxane solubility in DESs. For the DES which was characterized by the highest solubility of siloxanes, studies of physicochemical properties, i.e., viscosity, density, and melting point, were performed. DES composed of tetrapropylammonium bromide (TPABr) and tetraethylene glycol (TEG) in a 1:3 molar ratio was used as an absorbent in experimental studies in which several parameters were optimized, i.e., the temperature, absorbent volume, and model biogas flow rate. The mechanism of siloxanes removal was evaluated by means of an experimental FT-IR analysis as well as by theoretical studies based on σ-profile and σ-potential. On the basis of the obtained results, it can be concluded that TPABr:TEG (1:3) is a very effective absorption solvent for the removal of siloxanes from model biogas, and the main driving force of the absorption process is the formation of the hydrogen bonds between DES and siloxanes.

  • Renewable Energy in the Pomerania Voivodeship—Institutional, Economic, Environmental and Physical Aspects in Light of EU Energy Transformation
    • Bartłomiej Iglinski
    • Karol Flisikowski
    • Michał Pietrzak
    • Urszula Kiełkowska
    • Mateusz Skrzatek
    • Anas Zyadin
    • Natarajan Karthikeyan
    • Bartłomiej Igliński
    2021 Full text ENERGIES

    In the era of globalization and rapid economic growth, affecting most world economies, increased production and consumption are leading to higher levels of energy production and consumption. The growing demand for energy means that energy resources from conventional sources are not sufficient; moreover, its production generates high costs and contributes to the emission of greenhouse gases and waste. In view of the above, many countries have opted to implement an energy transformation. The energy transition allows the transition from an energy system based on conventional fuels to an energy system based mainly on renewable energy (RE) and low-emission sources. In the EU, the development of a “green economy” has become a strategic goal in the fight against climate change. The development of RE offers the possibility to improve the energy security of a given country and the entire EU. New, innovative technologies of RE also increase the attractiveness and competitiveness of the economies of the Member States. In line with the EU strategy, the activities carried out aim to achieve a situation in which, in 2050, the activities of economies will not endanger the environment. The main purpose of this article was the assessment of the RE sector in the Pomerania region in the context of energy transformation. To achieve this goal, PEST analysis regarding the functioning of the RE sector in the selected Polish region was used and the potential of the RE sector was determined using GIS tools on the basis of physical conditions. The article presents the research hypothesis that the RE sector within the Pomerania Voivodeship possesses appropriate energy potential, which will allow this Voivodeship to become an energy self-sufficient region based on the use of these energy sources (according to EU strategy). The implementation of the goal set in the article allowed for the verification of the research hypothesis, where the determined energy potential from the RE sector would cover the Voivodeship’s needs due to the use of electricity and heat. The conducted research shows that the RE sector in these regions has high energy potential to meet the criteria outlined in EU legal documents and to implement them successfully within the intended period.

  • Repeated Projectile Impact Tests on Multi-Layered FibrousCementitious Composites
    • G. Murali
    • Sallal R. Abid
    • Hakim Abdelgader
    • Y. H. Mugahed Amran
    • Mohammad Shekarchi
    • Krzysztof Wilde
    2021 International Journal of Civil Engineering

    This research aims to experimentally evaluate the behaviour of multi-layered fibrous cementitious composites withintermediate Glass Fibre Meshes (GFM) under repeated projectile load. The impact load was subjected through a convexedge projectile needle at a low velocity on cylindrical specimens of three-layered fibrous cementitious composites, whichhave two different steel fibre distributions. In series A mixtures, a constant steel fibre dosage of 2.5% by volume was used.On the other hand, the fibre dosage of the outer layers was 3.0%; while it was 1.5% in the middle layer of series B mixtures.The number of intermediate GFM was the variable that distinguishes the mixtures of each series. The resistance toprojectile impacts was evaluated on the basis of penetration depth, near surface distortion, weight loss, damage ratio andfailure pattern. The test results showed that due to the combined effect of steel fibre and GFM, significantly lower weightlosses were recorded for series A and B specimens compared with reference specimens. However, the different fibredistributions (series B) led to lower penetration depths and weight losses with less surface distortion compared with thefixed fibre distribution (series A). The reduction in the destroyed front surface area of series A specimens compared withreference specimens ranged from 27.8 to 38.1%; while that of series B specimens ranged from 34.8 to 53.4%. In addition, asimplified analytical model was introduced to predict the ejected composite mass. The model predictions were found to bein good agreement with the experimental masses.

  • Reprezentacja danych dźwiękowych w kontekście metod uczenia maszynowego
    • Tymoteusz Cejrowski
    2021

    Dźwięk odgrywa kluczową rolę w przekazywaniu informacji lub ostrzeganiu o niebezpieczeństwie. Do opracowania wydajnego cyfrowego asystenta głosowego zdolnego do efektywnej współpracy z człowiekiem niezbędne jest użycie algorytmów opisujących sygnał dźwiękowy w formie cyfrowej. W poniższej pracy skategoryzowano i opisano najpowszechniejsze metody opisu sygnałów audio używanych jako wejścia dla algorytmów uczenia maszynowego. Wskazano ich zastosowania i potencjalne problemy związane z ich wykorzystaniem.

  • Research and applications of active bearings: A state-of-the-art review
    • Łukasz Breńkacz
    • Łukasz Witanowski
    • Marta Drosińska-Komor
    • Natalia Szewczuk-Krypa
    2021 MECHANICAL SYSTEMS AND SIGNAL PROCESSING

    Controllable/active bearings are mainly associated with active magnetic bearings (AMBs), whereas active bearing control is also found in many types of bearings, e.g. fluid, gas and hybrid bearings. The article presents a review of the literature describing the structure and results of studies of active bearings. Active control brings a number of benefits resulting in the fact that their use as a support for rotors becomes increasingly common. This article introduces readers to the different methods of controlling radial bearings and provides detailed information on various technical solutions. Furthermore, the paper presents the characteristics of bearings as well as the basic advantages, disadvantages and possibilities offered by active control of various types of bearings. The influence of active control on rotor dynamics as well as on bearing friction, temperature control, permissible operating time, the environment (possibility of using safer lubricants) and operating safety is presented. The final part of the article presents possible directions of development of active bearings (ABs).

  • Research of Emergency Modes of Wind Power Plants Using Computer Simulation
    • Mohamed Zaidan Qawaqzeh
    • Oleksandr Miroshnyk
    • Taras Shchur
    • Robert Kasner
    • Adam Idzikowski
    • Weronika Kruszelnicka
    • Andrzej Tomporowski
    • Patrycja Bałdowska-Witos
    • Józef Flizikowski
    • Marcin Zawada
    • Krzysztof Doerffer
    2021 Full text ENERGIES

    The aim of this study is to investigate changes in the wind power plant energy production parameters under the conditions of sudden wind changes and voltage drop. To achieve these goals, a simulation of operation of wind power plants was performed. Twelve wind turbines with variable rotational speed equipped with a Fuhrländer FL 2500/104 asynchronous double-fed induction generator (DFIG) were used, each with an installed capacity of 2.5 MW. A general scheme of a wind power plant has been developed using a modular-trunk power distribution scheme. The system consists of wind power modules and a central substation, which allows total power to be supplied to the power system at a voltage of 35 kV. The central substation uses two high voltage switchgears. Four modules were used, each of them consisting of three wind turbines, with a power of 7.5 MW. The simulation of the wind turbines was performed in the MATLAB® Simulink® software environment. The mode of response of the turbines to a change in wind speed, a voltage drop in the 35 kV voltage system, and a one-phase short circuit to the ground in the system of 10.5 kV voltage was explored. The results show that a sudden voltage drop and the appearance of short circuits influence the wind power plant (WPP) operation in a different way independent of regulation mode. The power generation from WPP will be limited when voltage drop occurred for both AC and Voltage regulation mode and during short circuits while WPP is set on AC regulation mode.

  • Research on the Use of Mobile Devices and Headphones on Pedestrian Crossings—Pilot Case Study from Slovakia
    • Miroslava Mikusova
    • Joanna Wachnicka
    • Joanna Żukowska
    2021 Full text Safety

    The topic of the use of mobile devices and headphones on pedestrian crossings is much less explored in comparison to the use of the mobile phone while driving. Recent years have seen many discussions on this issue, especially in foreign countries. The Slovak Republic, however, has not been giving it enough attention (and it is not mentioned in the National Road Safety Plan for the Slovak Republic from 2011 to 2020). This paper aims to draw attention to this issue. It presents basic outputs of a pilot study on pedestrian safety, with a focus on the use of mobile devices and headphones at selected non-signalized pedestrian crossings in three Slovak cities. Overall, 9% of pedestrians used headphones or mobile devices at observed pedestrian crossings (4% of them used headphones, 1% used headphones and at same time used their mobile phone, 2% made phone calls and 2% used their mobile phones). While these numbers can be considered relatively low, the study proved that during weekdays every 2 min someone was using the crossing without fully focusing on crossing the road safely. Another main finding was that although the safety risk at pedestrian crossings is increased by factors such as rush hour traffic or reduced visibility, pedestrian behavior related to the use of mobile phones and headphones does not change. A safety assessment was also carried out at the crossings. The results show that pedestrian behavior is not affected by the level of safety of the crossing (e.g., visibility of the crossing for drivers). The results of the presented analysis suggest that action is needed to change that. Due to the lack of information about accidents involving pedestrians using mobile phones and headsets when crossing the road, no relevant statistical data could be analyzed. The dataset collected can be used as a basis for further investigation or comparisons with other countries of the relevant indicators. In future work, we would like to include a pedestrian– driver interaction factor focusing on driver speed behavior in relation to pedestrians (who are on or are about to step onto a pedestrian crossing) and identify critical situations caused by improper behavior of drivers and/or pedestrians. This will help to understand speed adjustment problems related to pedestrian crossings.

  • Researching Digital Society: Using Data-Mining to Identify Relevant Themes from an Open Access Journal
    • Judith Schoßböck
    • Noella Edelmann
    • Nina Rizun
    2021

    Open Access scholarly literature is scientific output free from economic barriers and copyright restrictions. Using a case study approach, data mining methods and qualitative analysis, the scholarly output and the meta-data of the Open Access eJournal of e-Democracy and Open Government during the time interval 2009–2020 was analysed. Our study was able to identify the most prominent research topics (defined as thematic clusters) of the journal, their evolution over time and how these were influenced by journal management factors. This kind of analysis helps editors to develop an editorial strategy, decide on the thematic development of the journal and address the expectations of future authors of the journal. It further can provide insights about research themes and trends within a scholarly community and their development over time.

  • Researching Digital Society: Using Data-Mining to Identify Relevant Themes from an Open Access Journal
    • Judith Schoßböck
    • Noella Edelmann
    • Nina Rizun
    2021 Full text

    Open Access scholarly literature is scientific output free from economic barriers and copyright restrictions. Using a case study approach, data mining methods and qualitative analysis, the scholarly output and the meta-data of the Open Access eJournal of e-Democracy and Open Government during the time interval 2009–2020 was analysed. Our study was able to identify the most prominent research topics (defined as thematic clusters) of the journal, their evolution over time and how these were influenced by journal management factors. This kind of analysis helps editors to develop an editorial strategy, decide on the thematic development of the journal and address the expectations of future authors of the journal. It further can provide insights about research themes and trends within a scholarly community and their development over time

  • Reshaping financial systems: The role of ICT in the diffusion of financial innovations – Recent evidence from European countries
    • Ewa Lechman
    • Adam Marszk
    2021 Full text TECHNOLOGICAL FORECASTING AND SOCIAL CHANGE

    Exchange-traded funds (ETFs) are among the fastest-growing types of innovative financial products. The emergence and spread of these instruments have been facilitated by the digital revolution. Information and communication technology (ICT) is profoundly reshaping the global economic landscape, laying solid foundations for unrestricted and unbounded flows of information and knowledge, eliminating information asymmetries, and furthering the rapid diffusion of financial innovations worldwide. This work contributes to the literature by exploring the linkages between variations in ICT penetration and the development and expansion of financial innovation on stock exchanges in ten European countries: France, Germany, Hungary, Italy, Norway, Poland, Spain, Switzerland, Turkey, and the United Kingdom. The analysis covers the period from 2004 to 2019, and uses panel and country-specific regression models to verify the relationship hypothesized between increasing ICT penetration and the development of exchange-traded funds. Our findings indicate that ICT spreads evenly in all the countries, laying solid foundations for the development of innovative financial products. We also find that ICT positively influences the diffusion of ETFs, regardless of the other possible determinants considered; however, despite the high level of ICT adoption in most of the economies analyzed, ETF market development has not been universal, with substantial between-country differences.

  • Reshaping the Gdańsk Shipyard—The Birthplace of the Solidarity Movement. The Complexity of Adaptive Reuse in the Heritage Context
    • Piotr Lorens
    • Łukasz Bugalski
    2021 Full text Sustainability

    The Gdańsk Shipyard—the birthplace of the Solidarity movement—is host to a unique example of a multi-layered brownfield redevelopment project, an area that is burdened by a complex history, overlapping heritage, and multiple memories. These circumstances require an integrated yet differentiated approach to the site’s heritage and make the creation of one homogeneous narration of its future impossible. At the same time, the size of the area, as well as its location within Gdańsk city centre, has meant that its future has been the subject of numerous discussions and speculations conducted over the last 20 years—starting from the creation of a large-scale open-air museum and continuing to the localization of the new Central Business District of the city. Consequently, that broad discussion carried out regarding the scope of redevelopment projects has been rooted in the possible introduction of diverse models of adaptive reuse. This variety of possible approaches also includes discussion on the mode of integrating heritage in the redevelopment processes. The goal of this paper—written just before the initiation of the final stage of the conceptual part of the project—is to present the complexity of approaches to issues related to redevelopment and heritage preservation.

  • Revalorisation of the Szewalski’s concept of the law of varying the last-stage blade retraction in a gas-steam turbine
    • Paweł Ziółkowski
    • Stanisław Głuch
    • Tomasz Kowalczyk
    • Janusz Badur
    2021 Full text E3S Web of Conferences

    The article presents the implementations of the free vortex law to the blade of the last stage of a gas-steam turbine. First, a thermodynamic analysis was carried out, determining the parameters at the inlet, then the number of stages of the high and low-pressure part of the turbine was constructed, together with the kinematics and velocity vectors for subsequent stages of the axial turbine. The last step of article was to take into account the law of variation of the peripheral component of the velocity of the medium working with the radius of the turbine in a discrete way and to make a 3D drawing of the resulting geometry. When creating the spatial model, the atlas of profiles of reaction turbine stages was used.

  • Revealing dynamic changes of the volatile profile of food samples using PTR–MS
    • Tomasz Majchrzak
    • Wojciech Wojnowski
    • Andrzej Wasik
    2021 FOOD CHEMISTRY

    Volatile compounds carry valuable information regarding the properties of foodstuffs. Volatiles emitted from food can be used as, for example, indicators of quality, shelf-life, or authenticity. A better understanding of the multitude of transformations which occur during food processing could facilitate the optimisation of production, increase the desirability of food products, and also their wholesomeness. However, as some of these transformations are fast-paced, it is necessary to monitor them using techniques which enable real-time determination of volatiles, such as proton transfer reaction–mass spectrometry (PTR–MS). Recent years have seen a marked increase in its use in food analysis, since it can be used to obtain insight into the dynamics of the monitored processes and can be the basis for precise quality control methods for food processing. This review highlights recent works in which PTR–MS was used in monitoring during foodstuffs production, preparation and storage.

  • Revealing the Frank–Evans “Iceberg” Structures within the Solvation Layer around Hydrophobic Solutes
    • Joanna Grabowska
    • Anna Kuffel
    • Jan Zielkiewicz
    2021 Full text JOURNAL OF PHYSICAL CHEMISTRY B

    Using computer simulations, the structural properties of solvation water of three model hydrophobic molecules, methane and two fullerenes (C60 and C80), were studied. Systems were simulated at temperatures in the range of 250−298 K. By analyzing both the local ordering of the molecules of water in the solvation layers and the structure of hydrogen bond network, it is shown that in the solvation layer of hydrophobic molecules, ordered aggregates consisting of water molecules are formed. Even though it is difficult to define the exact structure of these aggregates, their existence alone is clearly noticeable. Moreover, these aggregates become more pronounced with the decrease of temperature. The existence of the ordered aggregates around the hydrophobic solutes complies with the concept of “icebergs” proposed by Frank and Evans.

  • Reversible Data Hiding in Encrypted DICOM Images Using Cyclic Binary Golay (23, 12) Code
    • Mariusz Dzwonkowski
    • Roman Rykaczewski
    2021 Full text IEEE Access

    In this paper, a novel reversible data hiding method for encrypted images (RDHEI) is proposed. An efficient coding scheme based on cyclic binary Golay (23, 12) code is designed to embed additional data into the least significant bits (LSBs) of the encrypted image. The most significant bits (MSBs) are used to ensure the reversibility of the embedding process. The proposed scheme is lossless, and based on the receiver’s privileges, allows recovery of marked data, original data and embedded data. Furthermore, the scheme can be used with any type of data, however it is best suited to 16-bit DICOM images of monochrome photometric interpretation. A modification to the standard DICOM network model was also introduced, to point out an example application of the proposed RDHEI method, i.e. an anonymized data storage outsourcing. A computer-based analysis has been carried out and simulation results are shown at the end of this paper.

  • Review of Cybersecurity Assessment Methods: Applicability Perspective
    • Rafał Leszczyna
    2021 Full text COMPUTERS & SECURITY

    Cybersecurity assessments are crucial in building the assurance that vital cyberassets are effectively protected from threats. Multiple assessment methods have been proposed during the decades of the cybersecurity field. However, a systematic literature search described in this paper reveals that their reviews are practically missing. Thus, the primary objective of this research was to fulfil this gap by comprehensively identifying and analysing cybersecurity assessment methods described in the scientific literature. A structured research method and transparent criteria were applied for this purpose. As a result, thirty-two methods are presented in this paper. Particular attention is paid to the question of the methods’ applicability in realistic contexts and environments. In that regard, the challenges and limitations associated with the methods’ application as well as potential approaches to addressing them have been indicated. Besides, the paper systematises the terminology and indicates complementary studies which can be helpful during assessments. Finally, the areas that leave space for improvement and directions for further research and development are indicated. The intention is to support researchers and practitioners in choosing the method to be applied in their assessments and to indicate the areas that can be further explored.

  • Review of International Standards and Policy Guidelines for Smart Sustainable Cities
    • Elsa Estevez
    • Karina Cenci
    • Pablo Fillottrani
    • Tomasz Janowski
    2021 Full text

    Smart cities are often criticized for preoccupation with technology, for ignoring the negative effects of technology, for irrelevance to the needs of the poor, and for ubiquitous data collection creating perfect conditions for surveillance societies and autocratic states. In response, cities pursue smartness and sustainability simultaneously, becoming global (by participation in global digital networks) and local (by addressing local needs and circumstances) at the same time. In the pursuit of smart sustainable cities, they make explicit policy decisions about how technology should serve their residents, businesses and visitors, and avoid disrupting them. Many decisions are about standards—which standards should be followed and how, and increasingly, standards and policy guidelines are adopted by cities from international organizations, circumventing national authorities. This chapter reviews international standards and policy guidelines published by international standards organizations or intergovernmental bodies, with stated goals to support member states in the development and management of smart sustainable cities. We conducted the review through exploratory research and comparative policy analysis. The result could be used to raise awareness and address knowledge needs among city managers, policy analysts, and smart city researchers.

  • Review of Selected Methods for Prediction of Added Resistance in Following Waves
    • Sebastian Bielicki
    • Michał Kalbarczyk
    2021

    The added resistance in waves is a mean value of non-linear, second order reaction of a ship to incoming waves. In the beginning of the 20th century, the experimental methods for investigation of ship hydrodynamics at model scale were developed. They allowed the evaluation of added resistance by measurements in irregular waves (directly) or by measurements in regular waves (in-direct method). The main goal was to find more precise information about the margin for on-board installed engine power to fulfill operational demands of designed vessel. In the early sixties of the 20th century, numerical methods appeared, enabling the seakeeping analyses in frequency domain, and including the methods for determination of added resistance due to head waves. These computational methods, based on gravity character of added resistance, applied the potential flow theory and were mainly determined to cope with head waves. However, the issue of route optimization as well as the phenomena of broaching and surf-riding of vessels going through following and aft-quartering waves gained more attention recently, what demands accurate prediction methods applicable also for these conditions. To avoid dangerous behavior of a vessel, it is necessary to increase the speed, which means that the ship has to maintain a power margin for this operation. The level of added power can be assessed basing on computations of added resistance in waves coming from mentioned directions. The following paper presents the comparison of the results obtained from selected computational methods, including potential methods, semi-empirical formulae and RANS-CFD, with results of dedicated model experiments.

  • Review of Sustainability Assessment Tools for Buildings and Cities
    • Gulben Calis
    • Dorota Kamrowska-Załuska
    • Ezgi Kocaman
    • Merve Kuru
    2021

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  • Review on robust laser light interaction with titania – Patterning, crystallisation and ablation processes
    • Katarzyna Siuzdak
    • Łukasz Haryński
    • Jakub Wawrzyniak
    • Katarzyna Grochowska
    2021 PROGRESS IN SOLID STATE CHEMISTRY

    Titanium dioxide is regarded as a very promising semiconducting material that is widely applied in many everyday-use products, devices, and processes. In general, those applications can be divided into energy or environmental categories, where a high conversion rate, and energy and power density are of particular interest. Therefore, many efforts are being put towards the elaboration of novel production routes, and improving the material's properties such as light absorption, and charge concentration, as well as development of the surface area to improve the efficiency of particular process. Typically, bulk doping and surface modifications can be distinguished, applying some sol-gel, chemical vapour deposition, and hydrothermal processes in the presence of dopant precursors. However, development of waste disposal and many up-scaling optimisation routes have to be performed to consider the proposed path worthy of wide scale, commercial use. In contrast to the wet-chemistry methods, laser technology offers unique material treatment by light of a particular wavelength, fluence, and pulse repetition rate. In consequence, the changes can affect the bulk structure or only its surface. Such an approach provides a wide range of possible modifications without the use of any chemical products, and therefore avoids the formation of any by-products. Moreover, knowing the facile scaling up of laser treatment towards a higher technology readiness level, we believe such an approach stands out from synthesis and/or modification carried out first in small flasks and using small amounts of substrates. In this review, we would like to emphasize the results of selected studies presenting possible laser beam and titania interactions ensuring changes in the surface zone or deeply in the internal structure. The works evoked here indicate that this powerful technique can, among other things, provide slight surface melting of titania nanotubes, their phase transition from an amorphous solid to anatase or, when the fluence exceeds a certain threshold, the ablation of material out of the titania target.