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  • Cu supported on various oxides as a candidate catalyst for dry methane reforming in DIR-SOFCs systems
    • Adrian Mizera
    • Patryk Błaszczak
    • Beata Bochentyn
    • Radosław Lach
    • Ewa Drożdż
    2022 Pełny tekst INTERNATIONAL JOURNAL OF HYDROGEN ENERGY

    A series of Cu-support systems were tested as potential candidates for DIR-SOFC (Direct Internal Reforming SOFC) catalysts towards a dry reforming of methane (DRM). The various supports (-Al2O3, CeO2, ZrO2, SrTiO3) with comparable specific surface area (SSA), and additionally -Al2O3 with SSA an order of magnitude larger than that of the other supports has been applied. The obtained Cu-support systems were characterized in terms of structure (XRD, XPS), microstructure (SEM), redox properties (TPR /TPOx), and next their catalytic activity and selectivity in DRM reaction were tested. All Cu-support materials show catalytic activity in DRM reaction, but only activity of Cu-SrTiO3 is high (due to the incorporation of Cu into SrTiO3 structure). The catalytic activity of other materials depends on the copper oxidation state (Cu2+ and Cu+). The highest catalytic activity in DRM process was obtained for Cu-AlO(OH) catalyst thanks to an order of greater SSA than in the case of other systems.

  • Cu-Doped Layered Double Hydroxide Constructs the Performance-Enhanced Supercapacitor Via Band Gap Reduction and Defect Triggering
    • Xianyu Chu
    • Fanling Meng
    • He Yang
    • Wei Zhang
    • Tingting Qin
    • Zizhun Wang
    • Sebastian Molin
    • Piotr Jasiński
    • Weitao Zheng
    2022 ACS Applied Energy Materials

    Layered double hydroxides (LDHs) are regarded as the excellent electrode materials for supercapacitors because of their high theoretical capacitance and abundance. However, the poor conductivity and limited reaction kinetics of LDHs restrict their practical application severely. Herein, Cu is chosen from groups VIII/IB/IIB as dopants for Co-based LDH (CuCo-LDH). The designed metal–organic framework-derived hierarchical CuCo-LDH hollow nanoarrays integrated on nickel foam are fabricated via a facile in situ hydrolysis method. Consequently, the introduction of copper significantly enhances the local electron density of cobalt-based hydroxide, which enhances electronic conductivity and facilitates the charge transfer. Copper doping induces lattice defects, providing more active sites to improve the charge storage capacity. As a result, our CuCo-LDH electrode delivers a package-enhanced pseudocapacitive performance. The as-fabricated asymmetric supercapacitor CuCo-LDH//AC provides a relatively high energy density of 22 W h kg–1 and a remarkable cycling stability (91.3% after 10,000 cycles) towards practical applications of supercapacitors.

  • CULTURAL DETERMINANTS OF EVIDENCE-BASED HUMAN RESOURCES MANAGEMENT: A CROSS-COUNTRY ANALYSIS
    • Łukasz Sienkiewicz
    2022 Pełny tekst Zeszyty Naukowe. Organizacja i Zarządzanie / Politechnika Śląska

    Purpose: This paper aims at providing comparative analysis of the influence of cultural determinants on the managers’ perceptions of human resources management practices, as a factor conditioning application of evidence-based management. Design/methodology/approach: This article presents the study of 121 managers in Poland, on their perception of HRM practices and analyses the consistency of findings with the Hofstede cultural dimensions model. Structured questionnaire developed by Rynes et al. (2002) in the US and used by Tenhiälä et al. (2016) in Finland, Spain and South Korea including 34 items on management practices, employment practices, training and development, staffing and compensation and benefits have been used. Comparative analysis of managers’ perceptions in 5 countries have been performed, and analysed from the perspective of cultural determinants. Findings: Significant differences among analysed countries have been noted in relation to managers’ perceptions of HRM practices, interpreted using the Hofstede’s model of cultural determinants. Five dimensions have been identifies as the most likely determinant of observable differences. Cultural factors have been found to explain perceptions of HRM practices in Poland, as well as in countries with both similar cultural dimensions profiles or shared characteristics. Research limitations/implications: The empirical part – questionnnaire in Poland – was performed during Covid-19 pandemic, which might have affected the perceptions of managers on what works in relation to HRM practices, as well as the external conditions under which the research was performed changed significantly over the course of last two years. Practical implications: Findings from the managers’ survey have been analysed from the perspective of cultural determinants, therefore making a link between perceptions and measurable and well defined variables of cultural origin, as represented by Hofstede’s dimensions. This implies, that more attention should be paid to culturally-grounded differences in cases where more evidence-based practices are intended to be implemented in organisations. Originality/Value: Paper presents original research findings, by providing comparative evidence on the managers’ perceptions of HRM practices in cross-cultural context, with application of the Hofstede cultural dimensions model.

  • Curlicues generated by circle homeomorphisms
    • Justyna Signerska-Rynkowska
    2022 Pełny tekst GEOMETRIAE DEDICATA

    We investigate the curves in the complex plane which are generated by sequences of real numbers being the lifts of the points on the orbit of an orientation preserving circle homeomorphism. Geometrical properties of these curves such as boundedness, superficiality, local discrete radius of curvature are linked with dynamical properties of the circle homeomorphism which generates them: rotation number and its continued fraction expansion, existence of a continuous solution of the corresponding cohomological equation and displacement sequence along the orbit.

  • CURRENT SITUATION ON THE POLAND REAL ESTATE MARKET
    • Tetiana Osadcha
    • Oleksandr Melnychenko
    2022 Pełny tekst Współpraca Europejska

    In recent years the polish real estate market has been characterised by a significant increase in supply and demand. This was facilitated by a number of macroeconomic factors. In recent years, housing has been commissioned as 30 years ago. Therefore, the depth analysis issue of the causes and consequences for the Polish economy of these trends is now relevant. Among the reasons are significant economic growth, low interest rates on loans, rising welfare, low unemployment, stable inflation and, of course, the COVID-19 pandemic. We assess these and other reasons in this article in order to further forecast the real estate market's indicators. In addition, the Poland society is characterised by a significant proportion of those who want to own housing, not rent it. This is due to historical events and the incomes level of the population, which is still one of the poorest among the European Union member states, therefore real estate ownership is a sign of households' stability and economic security. At the same time, the purchase of housing is influenced by rather low interest rates on loans, which encourage the population to use the opportunities to buy housing on credit. That is why a significant amount of real estate is built for credit resources and purchased in this way.

  • Current Trends in Wick Structure Construction in Loop Heat Pipes Applications: A Review
    • Paweł Szymański
    • Dariusz Mikielewicz
    • Sasan Fooladpanjeh
    2022 Pełny tekst Materials

    Thermal control systems have been introduced as an important part of electronic devices, enabling thermal management of their electronic components. Loop heat pipe (LHP) is a passive two-phase heat transfer device with significant potential for numerous applications, such as aerospace applications, high-power LEDs, and solar central receivers. Its advantages are high heat transfer capability, low thermal resistance, long-distance heat transfer, and compact structure. The essential role of wick structures on the performance of LHPs has already been highlighted, but no comprehensive review is available that deals with different parameters such as LHP design and wick size, which are largely decisive and effective in achieving a practical level of thermal transmission governed by wick structures. To rely on this necessity, this article summarizes, analyzes, and classifies advancements in the design and fabrication of wick structures. The main conclusion to be drawn after careful monitoring and weighing of the related literature is that LHPs with composites and additively manufactured wicks show a higher heat transfer coefficient than other conventional structures. Indeed, future works should be focused on the design of more structurally efficient wicks, which may allow us to optimize materials and geometrical parameters of wick structure for higher heat transfer through LHPs.

  • Customizing nano-chitosan for sustainable drug delivery
    • Mostafa Saeedi
    • Omid Vahidi
    • Mohammad Reza Moghbeli
    • Sepideh Ahmadi
    • Mohsen Asadnia
    • Omid Akhavan
    • Farzad Seidi
    • Mohammad Rabiee
    • Mohammad Saeb
    • Thomas J. Webster
    • Rajender S. Varma
    • Esmaeel Sharifi
    • Ali Zarrabi
    • Navid Rabiee
    2022 JOURNAL OF CONTROLLED RELEASE

    Chitosan is a natural polymer with acceptable biocompatibility, biodegradability, and mechanical stability; hence, it has been widely appraised for drug and gene delivery applications. However, there has been no comprehensive assessment to tailor-make chitosan cross-linkers of various types and functionalities as well as complex chitosan-based semi- and full-interpenetrating networks for drug delivery systems (DDSs). Herein, various fabrication methods developed for chitosan hydrogels are deliberated, including chitosan crosslinking with and without diverse cross-linkers. Tripolyphosphate, genipin and multi-functional aldehydes, carboxylic acids, and epoxides are common cross-linkers used in developing biomedical chitosan for DDSs. Methods deployed for modifying the properties and performance of chitosan hydrogels, via their composite production (semi- and full-interpenetrating networks), are also cogitated here. In addition, recent advances in the fabrication of advanced chitosan hydrogels for drug delivery applications such as oral drug delivery, transdermal drug delivery, and cancer therapy are discussed. Lastly, thoughts on what is needed for the chitosan field to continue to grow is also debated in this comprehensive review article.

  • Czy ja umyłem ręce? Jak skutecznie dezynfekować i po co
    • Bartłomiej Cieślik
    2022 Pełny tekst

    Układ immunologiczny człowieka jest niezwykłym systemem, który stopniem złożoności dorównuje skomplikowaniu relacji ekonomicznych centralnej Europy. Ludzie zdają się być niezwykle odporny na ataki patogenów lecz nawet tak zaawansowane układy ja układ odpornościowy człowieka czasem zawodzą. Wiedza na temat prawidłowych metod stosowania oraz skuteczności poszczególnych środków dezynfekcyjnych może być kluczowa do utrzymania bezpiecznych relacji w społeczeństwie ogarniętym pandemią. Racjonalne użytkowanie antyseptyków oraz rozważne stosowanie antybiotyków również może mieć wpływ na rozwój przyszłych zagrożeń epidemiologicznych.

  • Czy kurtoza mierzy spiczastość rozkładu?
    • Błażej Kochański
    2022 Pełny tekst Wiadomości Statystyczne

    Celem artykułu jest przedstawienie i uzasadnienie interpretacji klasycznego współczynnika kurtozy jako miary grubości ogonów oraz zaproponowanie modyfikacji treści dydaktycznych w tym zakresie. W wielu polskich podręcznikach akademickich podaje się, że współczynnik kurtozy (lub ekscesu) mierzy „wysmukłość”, „spiczastość” lub „spłaszczenie” rozkładu. Taka interpretacja jest nieprawidłowa. Kurtoza mierzy bowiem w istocie stopień rozproszenia wartości cechy w ogonach rozkładu lub – innymi słowy – intensywność wartości skrajnych. W artykule wskazano, dlaczego starsze interpretacje, mówiące o kształcie wierzchołka krzywej gęstości, są niewłaściwe. Zaprezentowano przykładowe leptokurtyczne rozkłady spłaszczone i platykurtyczne rozkłady wysmukłe. Na podstawie danych z Diagnozy Społecznej z lat 2000–2015 wykazano, że w badaniach empirycznych wartość kurtozy wynika ze stopnia natężenia wartości odstających. Zaproponowano nowe sformułowania, które można wykorzystać w dydaktyce statystyki zamiast nieprawidłowych, stosowanych dotychczas.

  • Damage imaging algorithm for non-destructive inspection of CFRP/steel adhesive joints based on ultrasonic guided wave propagation
    • Erwin Wojtczak
    • Magdalena Rucka
    2022 Pełny tekst COMPOSITE STRUCTURES

    The paper concerns assessing the quality of the adhesive connection between a steel plate and the reinforcing CFRP laminate. A three-stage algorithm for non-destructive damage imaging was developed. As the first step, an initial study involving dispersion curves of joint components was executed to determine the material parameters and the appropriate excitation frequency. During the second step, damage identification in three-layer joints was performed using the weighted root mean square (WRMS) of the guided wave signals. A novel approach to determine the optimal values of WRMS parameters was proposed. Within the third step, the guided wavefield was recorded by scanning laser vibrometry. Visualization of the distribution of WRMS values on the surface of scanned specimens allowed efficient damage imaging. The application of statistical analysis (histograms) was used to prepare the final damage maps. The results of the investigations showed the high usefulness of the developed approach for imaging both intentionally introduced and unintended defects in adhesive joints.

  • Data Analysis in Bridge of Data
    • Wojciech Artichowicz
    • Krzysztof Drypczewski
    • Jerzy Proficz
    2022 Pełny tekst

    The chapter presents the data analysis aspects of the Bridge of Data project. The software framework used, Jupyter, and its configuration are presented. The solution’s architecture, including the TRYTON supercomputer as the underlying infrastructure, is described. The use case templates provided by the Stat-reducer application are presented, including data analysis related to spatial points’ cloud-, audio- and wind-related research.

  • Data and knowledge supporting decision-making for the urban Food-Water-Energy nexus
    • Mei-Hua Yuan
    • Joanna Bach-Głowińska
    • Pei-Te Chiueh
    • Yu-Sen Chang
    • Hsin-hsin Tung
    • Yu Chang-Ping
    • Hwong-wen Ma
    • Jacek Łubiński
    • Lo Shang-Lien
    2022

    Cities are hubs of innovation and wealth creation, and magnets for an increasing urban population. Cities also face unprecedented challenges in terms of food, water and energy scarcity, and governance and management. Urban environmental issues are no longer problems for experts to address but have become issues of public debate, in which knowledge from multiple sectors is needed to support inclusive governance approaches. Consequently, this chapter presents a knowledge platform to support policymakers, programme officers, field staff and others to help integrate Food-Water-Energy nexus considerations and goals into policy formulation and implementation for cities. In this context, this chapter begins with a qualitative literature review of the nexus concept. This is interpreted broadly in order to consider as wide a range of potential practices and processes as possible. Recommendations are presented for research and development, testing and implementation, as well as knowledge and communication. From this, findings and recommendations are synthesised into an appropriate framework to enable the Food-Water-Energy nexus, and these are provided at the end of this chapter. This chapter can serve as a useful reference for those working on policy and planning related to the Food-Water-Energy nexus at the urban level for regions worldwide.

  • Data Compression in Ultrasonic Network Communication via Sparse Signal Processing
    • Beata Zima
    • Octavio Reyes Márquez
    • Masoud Mohammadgholiha
    • Jochen Moll
    • Luca Marchi De
    2022 Pełny tekst

    This document presents the approach of using compressed sensing in signal encoding and information transferring within a guided wave sensor network, comprised of specially designed frequency steerable acoustic transducers (FSATs). Wave propagation in a damaged plate was simulated using commercial FEM-based software COMSOL. Guided waves were excited by means of FSATs, characterized by the special shape of its electrodes, and modeled using PIC255 piezoelectric material. The special shape of the FSAT, allows for focusing wave energy in a certain direction, accordingly to the frequency components of its actuation signal, which makes a larger monitored area available. The process begins when a FSAT detects and records reflection from damage in the structure, this signal is then encoded and prepared for transmission, using a combined approach, based on Compressed Sensing Matching Pursuit and Quadrature Amplitude Modulation (QAM). After codification of the signal is in binary, the information is transmitted between the nodes in the network. The message reaches the last node, where it is finally decoded and processed, to be used for damage detection and localization purposes. The main aim of the investigation is to determine the location of detected damage using reconstructed signals. The study demonstrates that the special steerable capabilities of FSATs, not only facilitate the detection of damage but also permit transmitting the damage information to a chosen area in a specific direction of the investigated structure.

  • Data from the Survey on Entrepreneurs’ Opinions on Factors Determining the Employment of the Gdańsk University of Technology Graduates
    • Michał Tomczak
    2022 Pełny tekst

    The dataset includes data from a survey on factors determining the employment of the Gdańsk University of Technology (Gdańsk Tech) graduates’ in the opinion of entrepreneurs. The survey was conducted in 2017. The research sample included 102 respondents representing various firms from the Pomeranian Voivodeship, Poland. The study concerned i.a. factors determining the decision to hire a candidate, methods of recruiting employees, methods for diagnosing the competencies of candidates, and opinions on recruiting Gdańsk Tech graduates who do not have extensive professional experience, considering variables such as the company size and business sector. To summarise, the entrepreneurs focus on the diagnosis of candidates’ competencies during a job interview, and have nothing against employing inexperienced graduates.

  • Data from the Survey on Gdańsk University of Technology Graduates’ Professional Careers
    • Michał Tomczak
    2022 Pełny tekst

    The dataset titled Data from the survey on Gdańsk University of Technology graduates’ professional careers includes data from a survey of Gdańsk University of Technology (Gdańsk Tech) graduates’ professional careers. The survey was conducted in 2017, two years after the respondents obtained graduate status. The research sample included 2553 respondents. The study concerned, i.a. the percentage of people working among graduates of the Gdańsk Tech, length of the job search period, job position, economic sector, company size, amount of remuneration, and also considers variables such as the faculty graduated. Summarising, the graduates’ general situation within the labour market was very good.

  • De la façon dont les réseaux sociaux se croisent dans la vie des migrants
    • David Duenas Cid
    2022

    Éste es un texto muy complicado de titular. A pesar de lo sugerente de la idea de escribir acerca de dos conceptos intensamente relacionados, como son el de migración y el de redes. Esta misma intensidad en su interrelación implica una multiplicidad de sentidos que complican el trabajo explicativo del científico social, por su cuantioso número de opciones, y el trabajo comprensivo del lector, por la posible confusión que esta situación genera.

  • Deciphering the Molecular Mechanism of Substrate-Induced Assembly of Gold Nanocube Arrays toward an Accelerated Electrocatalytic Effect Employing Heterogeneous Diffusion Field Confinement
    • Paweł Niedziałkowski
    • Adrian Koterwa
    • Adrian Olejnik
    • Artur Zieliński
    • Karolina Górnicka
    • Mateusz Brodowski
    • Robert Bogdanowicz
    • Jacek Ryl
    2022 Pełny tekst LANGMUIR

    The complex electrocatalytic performance of gold nanocubes (AuNCs) is the focus of this work. The faceted shapes of AuNCs and the individual assembly processes at the electrode surfaces define the heterogeneous conditions for the purpose of electrocatalytic processes. Topographic and electron imaging demonstrated slightly rounded AuNC (average of 38 nm) assemblies with sizes of ≤1 μm, where the dominating patterns are (111) and (200) crystallographic planes. The AuNCs significantly impact the electrochemical performance of the investigated electrode [indium–tin oxide (ITO), glassy carbon (GC), and bulk gold] systems driven by surface electrons promoting the catalytic effect. Cyclic voltammetry in combination with scanning electrochemical microscopy allowed us to decipher the molecular mechanism of substrate-induced electrostatic assembly of gold nanocube arrays, revealing that the accelerated electrocatalytic effect should be attributed to the confinement of the heterogeneous diffusion fields with tremendous electrochemically active surface area variations. AuNC drop-casting at ITO, GC, and Au led to various mechanisms of heterogeneous charge transfer; only in the case of GC did the decoration significantly increase the electrochemically active surface area (EASA) and ferrocyanide redox kinetics. For ITO and Au substrates, AuNC drop-casting decreases system dimensionality rather than increasing the EASA, where Au–Au self-diffusion was also observed. Interactions of the gold, ITO, and GC surfaces with themselves and with surfactant CTAB and ferrocyanide molecules were investigated using density functional theory.

  • Decisional DNA (DDNA) Based Machine Monitoring and Total Productive Maintenance in Industry 4.0 Framework
    • Syed Imran Shafiq
    • Cesar Sanin
    • Edward Szczerbicki
    2022 Pełny tekst CYBERNETICS AND SYSTEMS

    The entire manufacturing spectrum is transforming with the advent of Industry 4.0. The features of Set of Experience Knowledge Structure (SOEKS) and Decisional DNA (DDNA) were utilized for developing Virtual Engineering Objects (VEO), Virtual Engineering Process (VEP) and Virtual Engineering Factory (VEF), which in turn facilitate the creation of smart factories. In this study, DDNA based Machine Monitoring for Total Maintenance in Industry 4.0 framework is demonstrated. The concept of VEO is used for the Tool and Equipment Monitoring, while for the Plants Operations Monitoring and Quality Monitoring, VEP and VEF are employed. Query extraction feature of DDNA is exploited for Adaptive Control. This study shows that Machine Efficiency (ME) can be monitored along with analysis of machine KPI’s like breakdown time, setting time, and other losses. Moreover, reports can be generated efficiency-wise, breakdown-wise, operator-wise. The data of these reports is used to predict and make future decisions related to machine maintenance.

  • Deep eutectic solvent (DES) with silver nanoparticles (Ag-NPs) based assay for analysis of lead (II) in edible oils
    • Hameed Haq
    • Rafiat Bibi
    • Muhammad Balal
    • Faisal Safi
    • Sana Ullah
    • Roberto Castro-Muñoz
    • Grzegorz Boczkaj
    2022 Pełny tekst FOOD CHEMISTRY

    This paper presents an application of silver nanoparticles impregnated by Deep Eutectic Solvents (DES) as ultrasonication aided microextraction system for lead (II) determination in edible oils. The paper presents a systematic optimization of method parameters and examples of its application for analysis of real samples. Maximum recovery for lead (II) extraction was obtained for choline chloride and phenol with a 1:2 molar ratio. Optimum extraction conditions for 2g oil sample post-digested solution (10 mL, pH=2) require 1mL of Ag-nanoparticles solution (0,1mM) and per each 500 µL of DES and tetrahydrofurane. The limit of detection (LOD) and quantification (LOQ) were 0.28 µg/L and 0.94 µg/L. The developed method covers the entire range of expected levels of lead concentration in oil samples -parts per billion levels to higher ones. This method is many folds faster (only 6.5 minutes/sample are needed) as well as more sensitive comparing to already reported methods.

  • Deep eutectic solvents – A new platform in membrane fabrication and membrane-assisted technologies
    • Roberto Castro-Muñoz
    • Francesco Galiano
    • Alberto Figoli
    • Grzegorz Boczkaj
    2022 Pełny tekst Journal of Environmental Chemical Engineering

    Deep eutectic solvents (DESs) are a new class of solvents that can offset some of the primary drawbacks of typical solvents and ionic liquids (ILs). Since DESs fall into the guidelines of “Twelve Principles of Green Chemistry”, their implementation in several types of applications has exponentially increased over the last years. The usage of DESs has been directed to the designing, manufacture and purification of new materials and feedstocks. Very recently, great attention has been paid to new pioneering attempts aiming at DESs into the field of chemical engineering, including membrane science and technology. Even if just a few works have been currently reported in applying DESs in membranes, the consideration on this new type of solvents is continuously growing. This review compares and discusses the documented discoveries and breakthroughs carried out in applying DESs in membrane science. The scope of this review is emphasized in various scopes: i) new sustainable membrane preparation, ii) membrane-based technologies aided by DESs, iii) target molecules-DES interactions and iv) new membrane-DES structures providing enhanced physicochemical properties and thus separation performance. Here, besides the relevant insights in the field, we give the key hypotheses and strategies used by the scientists to reach a successful merging of both areas since the use of DESs in membranes is still challenging due to the compatibility issues of the DESs and membrane phase (either polymer and inorganic). The future directions and perspectives on using DESs in membranes are also given.

  • Deep Eutectic Solvents and Their Uses for Air Purification
    • Patrycja Janicka
    • Justyna Płotka-Wasylka
    • Jacek Gębicki
    2022 Pełny tekst Journal of Ecological Engineering

    Chemical compounds released into the air by the activities of industrial plants and emitted from many other sources, including in households (paints, waxes, cosmetics, disinfectants, plastic (PVC) flooring), may affect the environment and human health. Thus, air purification is an important issue in the context of caring for the condition of the environment. Deep eutectic solvents (DESs) as liquids with environmentally friendly properties (non-volatile, biodegradable, non-toxic, cheap, easy to prepare) are a promising solution to this problem. This paper reviews the advances made in the application of DESs as sorbents for the purification of atmospheric and indoor air. The potential of DESs and their subclasses (including SUPRAmolecular Deep Eutectic Solvents, SUPRADESs) applications in air purification processes were also summarized.The authors believe that this review can be useful for future readers as a starting point for research in the field of DESs and their application in air purification.

  • Deep eutectic solvents microbial toxicity: Current state of art and critical evaluation of testing methods
    • Mateusz Marchel
    • Hubert Cieśliński
    • Grzegorz Boczkaj
    2022 Pełny tekst JOURNAL OF HAZARDOUS MATERIALS

    Deep eutectic solvents (DESs) were described at the beginning of 21st century and they consist of a mixture of two or more solid components, which gives rise to a lower melting point compared to the starting materials. Over the years, DESs have proved to be a promising alternative to traditional organic solvents and ionic liquids (ILs) due to their low volatility, low inflammability, easy preparation, and usually low cost of compounds used in their preparation. All these properties encouraged researchers to use them in diverse fields and applications e.g., as extractants for biomolecules and solvents in pharmaceutical and cosmetic industries. Nevertheless, despite undeniable potential of DESs, there is still controversy about their toxicity. Besides the low number of studies on this topic, there are also some contradicting reports on biocompatibility of these solvents. Such misleading reports could be mainly attributed to the lack of well design standard protocol for DESs toxicity determination or the use of out-off-purpose methodology. Thus, to better apply DESs in green and sustainable chemistry, more studies on their impact on organisms at different trophic levels and the use of proper techniques are required. This review focuses on DESs toxicity towards microorganisms and is divided into three parts: The first part provides a brief general introduction to DESs, the second part discusses the methodologies used for assessment of DESs microbial toxicity and the obtained results, and finally in the third part the critical evaluation of the methods is provided, as well as suggestions and guidelines for future research.

  • Deep Eutectic Solvents or Eutectic Mixtures? Characterization of Tetrabutylammonium Bromide and Nonanoic Acid Mixtures
    • Andrey Shishov
    • Patrycja Makoś-Chełstowska
    • Andrey Bulatov
    • Vasil Andruch
    2022 Pełny tekst JOURNAL OF PHYSICAL CHEMISTRY B

    Deep eutectic solvents have quickly attracted the attention of researchers because they better meet the requirements of green chemistry and thus have the potential to replace conventional hazardous organic solvents in some areas. To better understand the nature of these mixtures, as well as expand the possibilities of their use in different industries, a detailed examination of their physical properties, such as density, viscosity, the nature of the interactions between their constituents, the phase diagrams, depression of their melting point, and interpretation of these results is necessary. In this work, the mixtures of tetrabutylammonium bromide (TBAB) and nonanoic acid (NA) in different molar ratios are theoretically and experimentally investigated by applying a phase diagram constructed on the basis of differential scanning calorimetry measurements and COSMO-RS model. Spectral properties are investigated based on Fourier transform infrared spectroscopy and density functional theory. The observed eutectic point indicates the formation of a DES in the TBAB−NA system in a 1:2 molar ratio. This is due to the presence of hydrogen bonds between the carboxyl group from the NA molecule and the bromine atom from the TBAB molecule. Other eutectic mixtures are most likely the solutions of TBAB in NA, in which hydrogen bonds predominate between acid molecules.

  • Deep learning approach on surface EEG based Brain Computer Interface
    • Łukasz Radzinski
    • Tomasz Kocejko
    2022

    In this work we analysed the application of con-volutional neural networks in motor imagery classification for the Brain Computer Interface (BCI) purposes. To increase the accuracy of classification we proposed the solution that combines the Common Spatial Pattern (CSP) with convolutional network (ConvNet). The electroencephalography (EEG) is one of the modalities we try to use for controlling the prosthetic arm. Therefor in this paper we exploited the subject dependent approach and show results for models trained individually for a particular subject. Although the ConvNets are design to work directly with EEG data, presented approach of joining CSP with ConvNet shows increase in accuracy of movement classification. In average, our approach resulted in ∼80% accuracy.

  • DEEP LEARNING BASED ON X-RAY IMAGING IMPROVES COXARTHROSIS DETECTION
    • Michał Maj
    • Jakub Borkowski
    • Jan Wasilewski
    • Sylwia Hrynowiecka
    • Adrian Kastrau
    • Mariusz Liksza
    • Patryk Jasik
    • Mariusz Treder
    2022

    Objective: The purpose of the study was to create an Artificial Neural Network (ANN) based on X-ray images of the pelvis, as an additional tool to automate and improve the diagnosis of coxarthrosis. The research is focused on joint space narrowing, which is a radiological symptom showing the thinning of the articular cartilage layer, which is translucent to X-rays. It is the first and the most important of the radiological signs of degenerative changes. Material and Methods: As part of the study, 13374 pelvis cases with 26748 X-ray images of the hip joints were collected. All images were cropped and added to the database with the associated annotations created by the team of three orthopaedists. For the test dataset, 20% of random cases were chosen to correspond to statistical degenerative changes types distribution. The classification task was performed in a two-stage process using Convolutional Neural Networks (CNNs). First, the localization model was trained to locate the bounding boxes (width, height, center coordinates) containing the hip joint with its immediate surroundings, which reduced the size of data and hence the computational power needed for classification. Then, cropped images were classified using another CNN, loosely based on CheXNet architecture. Results: The accuracy of the localization model, measured by the intersection over union metric, was more than 94%. Trained ANN correctly classified 87.4% of cases with a 95% confidence interval (95CI) equals 85.6-89.1%. Results of precision of 91.7% (95CI 90.6-92.7%), sensitivity of 93.5% (95CI 92.0-94.8%), and F1 score of 92.6% (95CI 91.5-93.6%) were achieved. Conclusions: Created ANN reached promising accuracy. Combined with the good automated detection of the hip joints, it could potentially aid the fast differentiation of stable and urgently required medical intervention patients. Acknowledgments: We acknowledge partial support from UE within the NCBiR Epionier program (WG-POPC.03.03.00-00-0008/16-00).

  • Deep learning-based waste detection in natural and urban environments
    • Sylwia Majchrowska
    • Agnieszka Mikołajczyk
    • Maria Ferlin
    • Zuzanna Klawikowska
    • Marta A. Plantykow
    • Arkadiusz Kwasigroch
    • Karol Majek
    2022 Pełny tekst WASTE MANAGEMENT

    Waste pollution is one of the most significant environmental issues in the modern world. The importance of recycling is well known, both for economic and ecological reasons, and the industry demands high efficiency. Current studies towards automatic waste detection are hardly comparable due to the lack of benchmarks and widely accepted standards regarding the used metrics and data. Those problems are addressed in this article by providing a critical analysis of over ten existing waste datasets and a brief but constructive review of the existing Deep Learning-based waste detection approaches. This article collects and summarizes previous studies and provides the results of authors’ experiments on the presented datasets, all intended to create a first replicable baseline for litter detection. Moreover, new benchmark datasets detect-waste and classify-waste are proposed that are merged collections from the above-mentioned open-source datasets with unified annotations covering all possible waste categories: bio, glass, metal and plastic, non-recyclable, other, paper, and unknown. Finally, a two- stage detector for litter localization and classification is presented. EfficientDet-D2 is used to localize litter, and EfficientNet-B2 to classify the detected waste into seven categories. The classifier is trained in a semi- supervised fashion making the use of unlabeled images. The proposed approach achieves up to 70% of average precision in waste detection and around 75% of classification accuracy on the test dataset. The code and annotations used in the studies are publicly available online1.

  • Defending against Fake VIP in Scant-Transparency Information Systems with QoS Differentiation
    • Jerzy Konorski
    2022 Pełny tekst INFORMATION SCIENCES

    In client-server information systems with quality of service (QoS) differentiation, Client may deplete Server’s resources by demanding unduly high QoS level. Such QoS abuse has eluded systematic treatment; known defenses using Client authorization, payments, or service request inspection prior to QoS assignment, are heuristic and environment-specific. We offer a game-theoretic approach on the premise that a service request is occasionally trusted to reduce the inspection cost. We call Fake VIP attack (FVA) a form of QoS abuse that consciously exploits Server’s trust. An FVA strategy instills trust to maximize Client’s utility gained from successful FVAs, whereas a trust strategy maximizes Server’s utility by trading her loss due to successful FVAs against the request inspection cost. We consider a realistic scant-transparency setting where only long-term utilities are observable. Against a probabilistic FVA strategy we design a trust strategy based on double-blind reputation. Assuming a memoryless service request stream we analyze the impact of the request inspection cost and information leakage on the utilities at the Stackelberg equilibrium of the arising game. Experimental comparison with a real-world internally correlated stream is also shown.

  • Deformable model of a butterfly in motion on the example of Attacus atlas
    • Zuzanna Kunicka-kowalska
    • Michał Landowski
    • Krzysztof Sibilski
    2022 Journal of the Mechanical Behavior of Biomedical Materials

    Insect wings can undergo significant chordwise (camber) as well as spanwise (twist) deformation during flapping flight but the effect of these deformations is not well understood. The shape and size of butterfly wings leads to particularly large wing deformations, making them an ideal test case for investigation of these effects. High-speed videogrammetry was used to capture the wing kinematics and deformations. The movements of selected markers on the wings of a living insect was observed. Created characteristics showing the displacement in a three-dimensional coordinate system identified the kinematics and deformations of the butterfly’s wings. These experimental results were then analyzed computationally using a high-fidelity, three-dimensional, unsteady Navier-Stokes flow solver. Computational fluid dynamics (CFD) simulations were carried out on the basis of the wing geometry of the large moth Attacus atlas. Six geometric and structural models of the Attacus atlas butterfly wing with various degrees of simplification were developed. Using these models, Fluid-Structure-Interaction (FSI) simulation studies were performed in the commercial Ansys software environment (Fluent and Mechanical). Computations of the wing beat cycle were carried out, obtaining pressure distributions, streamlines, vortex regions and cumulative force waveforms.

  • Deformacje filtracyjne i ich oddziaływanie na osiadanie podłoża na przykładzie zabytkowego obiektu sakralnego
    • Paweł Popielski
    • Tomasz Majewski
    • Bartosz Bednarz
    • Maciej Niedostatkiewicz
    2022 Pełny tekst Materiały Budowlane

    W artykule omówiono studium przypadku wykorzytując dane dotyczzące pęknięć i deformacji w zabytkowym budynku oraz przecieków wody w jego podłozu. Przedstawiono charakterytykę deformacji filyracyjnych gruntu z uwagi na jego rodzaj i przyczynę. Na podstawie danych z monitoringu poziomu wody gruntowej w okolicach obiketu przeanalizowano przecieki i wyznaczono strefy w których przekroczone zostało kryterium inicjacji procesu deformacji filtracyjnych. W pracy przedstawiono również koncepcje rozwiązań projektowych w zakresie zabezpieczenia budynku z uewagi na deformacj filtracyjne gruntu.

  • Degradation of 1,4-dioxane by sono-activated persulfates for water and wastewater treatment applications
    • Shirish H. Sonawane
    • Kirill Fedorov
    • Manoj P Rayaroth
    • Grzegorz Boczkaj
    2022 Pełny tekst Water Resources and Industry

    This paper presents a hybrid advanced oxidation process (AOP) based on sonocavitational activation of persulfate (PS) for degradation of 1,4-dioxane during wastewater treatment. Application of sono-cavitation effectively convert PS to radical species demonstrating synergistic effect by increasing the reaction rate and reducing the required energy for activation. It is economically feasible and deployed alternative to the direct thermal activation method. A single and two-stage injection of PS were compared to eliminate self-scavenging effects related to excess of oxidant in system. A GC-MS analysis was used to determine the degradation products of dioxane and to propose the degradation mechanism. The studies revealed that the degradation was significantly enhanced by the addition of PS at molar ratio of oxidant to pollutant 4 with a two-stage injection. Under optimal conditions at US density of 105 W/cm2, dioxane with an initial concentration of 100 mg/L was completely degraded in 120 min.

  • Degradation of tetracycline antibiotic utilizing light driven-activated oxone in the presence of g-C3N4/ZnFe LDH binary heterojunction nanocomposite
    • Reza Darvishi Cheshmeh Soltani
    • Elham Abolhasani
    • Masoumeh Mashayekhi
    • Najla Jorfi
    • Grzegorz Boczkaj
    • Alireza Khataee
    2022 Pełny tekst CHEMOSPHERE

    In the present study, a binary heterojunction nanocomposite composed of graphitic carbon nitride (g-C3N4) and Zn/Fe-contained layered double hydroxide (ZnFe LDH) was employed as heterogeneous catalyst for the decomposition of tetracycline (TC) antibiotic utilizing Oxone and UV light irradiation. The sole use of g-C3N4/ZnFe LDH as adsorbent led to the negligible elimination of TC. In addition, the sole use of Oxone or UV (photolysis) and even their combination were not effective enough to degrade the target pollutant, while the combined process of g-C3N4/ZnFe LDH/Oxone/photolysis revealed significantly enhanced (synergistic) degradation of TC (92.4% within 30 min). Indirect detection tests for the identification of free radical species indicated the major role of both hydroxyl (•OH) and sulfate (SO4•−) radicals in the degradation of TC by the g-C3N4/ZnFe LDH/Oxone/photolysis system. The elimination of TC followed a pseudo-first order kinetic model. The complete degradation of TC (degradation efficiency of 100%) was achieved within the reaction time of 25 min when ultrasound (US) was applied as enhancing agent. Furthermore, the results of total organic carbon (TOC) analysis were used to exhibit progress in the mineralization of the pollutant. The bioassay results indicated the decreased toxicity of the process effluent toward microbial population of Escherichia coli after the treatment.

  • Demolition of the cereal elevator building located in the conservation protection zone in the aspect of technical, functional-utility and economic conditions
    • Maciej Niedostatkiewicz
    • Tomasz Majewski
    2022 Pełny tekst Inżynieria Bezpieczeństwa Obiektów Antropogenicznych

    The paper presents a description of the technical condition of the Grain Elevator building situated on the port quay, which after many years of operation has been decommissioned. The immediate reason for the cessation of operation was the change in the use profile of the port quay, which caused the handling of other goods at the quay than the bulk materials originally stored in Elewator Zbożowy. The work contains a detailed analysis of the technical condition of the building, also taking into account the functional and utility aspect as well as the economics of renovation works. The article showed that despite the location of the building in the conservation protection zone, the optimal solution was the demolition of Grain Elevator and its reconstruction of a new warehouse facility with parameters adapted to the current needs and target handling capacity of the port quay

  • Dependence of Housing Real Estate Prices on Inflation as One of the Most Important Factors: Poland’s Case
    • Oleksandr Melnychenko
    • Tetiana Osadcha
    • Anatoliy Kovalyov
    • Valerii Matskul
    2022 Pełny tekst Real Estate Management and Valuation

    The study aimed to examine the impact of inflation on the real estate market using Polish panel data for the last 13 years. It is based on a panel model, where price changes of one square meter of housing are determined as a function in changes of inflation, the central bank's base rate, dwellings built, as well as new mortgage loans. The quarterly dynamics of the average price of 1 square meter of housing in Poland’s eight largest cities in the 2009-2021 period was studied. This price was modeled and predicted using one of the Box-Jenkins time series models: the Holt-Winter model of exponential smoothing with a damped trend. The forecasting results showed a small (up to 4%) relative error in comparison with the actual data. In addition, the moment (2017) of the price trend change was found. Therefore, piecewise linear regressions with high regression coefficients were used when modeling the impact of inflation changes on the real estate market indicators under consideration. The results obtained provide valuable insight into the relationship of real estate market indicators, allowing consumers to predict available options and make decisions in accordance with their preferences.

  • DEPO: A dynamic energy‐performance optimizer tool for automatic power capping for energy efficient high‐performance computing
    • Adam Krzywaniak
    • Paweł Czarnul
    • Jerzy Proficz
    2022 SOFTWARE-PRACTICE & EXPERIENCE

    In the article we propose an automatic power capping software tool DEPO that allows one to perform runtime optimization of performance and energy related metrics. For an assumed application model with an initialization phase followed by a running phase with uniform compute and memory intensity, the tool performs automatic tuning engaging one of the two exploration algorithms—linear search (LS) and golden section search (GSS), finds a power cap optimizing a given metric and sets it for the remaining computations. The considered metrics include energy (E), energy-delay sum, energy-delay product. We present experimental results obtained for a set of benchmarks that differ in compute and memory intensity—parallel custom built OpenMP implementations of: numerical integration, heat distribution simulation (HEAT), fast Fourier transform (FFT), and additionally NAS parallel benchmarks: CG, MG, BT, SP, and LU. Tests were performed using multi-core CPUs that are representatives of modern servers and the desktop family: 2 Intel Xeon E5-2670 v3 CPU (Haswell-EP) and Intel i7-9700K CPU (Coffee Lake). The results show that our approach enabled considerable improvements for the tested metrics, for example, for HEAT and Coffee Lake we minimized energy by 50% at the cost of a 15% increase in execution time (LS), for FFT energy was minimized by 40% at a 25.5% increase in execution time (GSS), for SP and Haswell energy was minimized by 25% at the cost of an 18.5% time increase and for Coffee Lake energy was decreased by 56% with a 12% time increase.

  • Design and Analysis of Artificial Neural Network (ANN) Models for Achieving Self-Sustainability in Sanitation
    • Mahesh Ganesapillai
    • Aritro Sinha
    • Rishabh Mehta
    • Aditya Tiwari
    • Vijayalakshmi Chellappa
    • Jakub Drewnowski
    2022 Pełny tekst Applied Sciences-Basel

    The present study investigates the potential of using fecal ash as an adsorbent and demonstrates a self-sustaining, optimized approach for urea recovery from wastewater streams. Fecal ash was prepared by heating synthetic feces to 500 °C and then processing it as an adsorbent for urea adsorption from synthetic urine. Since this adsorption approach based on fecal ash is a promising alternative for wastewater treatment, it increases the process’ self- sustainability. Adsorption experiments with varying fecal ash loadings, initial urine concentrations, and adsorption temperatures were conducted, and the acquired data were applied to determine the adsorption kinetics. These three process parameters and their interactions served as the input vectors for the artificial neural network model, with the percentage urea adsorption onto fecal ash serving as the output. The Levenberg–Marquardt (TRAINLM) and Bayesian regularization (TRAINBR) techniques with mean square error (MSE) were trained and tested for predicting percentage adsorption. TRAINBR was demonstrated in our study to be an ideal match for improving urea adsorption, with an accuracy of R = 0.9982 and a convergence time of seven seconds. The ideal conditions for maximum urea adsorption were determined to be a high starting concentration of 13.5 g.L−1; a low temperature of 30 °C, and a loading of 1.0 g of adsorbent. For urea, the improved settings resulted in maximum adsorption of 92.8%.

  • Design and Characterization of a Planar Structure Wideband Millimeter-Wave Antenna with Wide Beamwidth for Wearable off-body Communication Applications
    • Ullah Ubaid
    • Magdalena Kozieł
    • Anna Pietrenko-Dąbrowska
    2022 IEEE Antennas and Wireless Propagation Letters

    This letter presents the design of a planar single-layer wideband antenna featuring wide beamwidth has well as high and stable in-band gain. The proposed antenna is a planar monopole fed by a bottom-grounded coplanar waveguide to realize wide beamwidth in both the xz- and yz-planes. Simultaneous optimization of all adjustable antenna parameters, carried out at the full-wave electromagnetic simulation level. The constructive interference of the radiated fields resulting in impedance bandwidth of more than 2 GHz, from 27 GHz to 29 GHz. Along with a stable realized gain (>11 dBi) in the operating frequency band. The proposed antenna maintains a directional radiation pattern in the broadside direction. Merging the radiated modes of the slots and the parasitic patch elements also extends the antenna beamwidth to roughly ±35o with respect to the broadside direction. Following a detailed theoretical analysis, the antenna is validated numerically and experimentally, both in the free space and on a human volunteer chest and arm.

  • Design and Implementation of a Dual-band Filtering Wil-kinson Power Divider Using Coupled T-shaped Dual-band Resonators
    • Sobhan Roshani
    • Bartosz Kozieł
    • Saeed Roshani
    • Faeeh Sadat Mehr
    • Stanisław Szczepański
    2022 Pełny tekst ENERGIES

    The paper introduces a novel structure of a dual-band filtering Wilkinson power divider (WPD). Its essential component is a dual-band bandpass filter (BPF), implemented using coupling lines and two T-shaped resonators. The BPF is incorporated into the divider structure to suppress the unwanted harmonics within the circuit. The latter is achieved owing to a wide stopband of the filter. The deigned dual-band WPD can suppress third unwanted harmonics in both channels with high levels of attenuation. The designed dual-band WPD operates at 2.6 GHz and 3.3 GHz with the return loss of 22.1 dB and 22.3 dB at the operating frequencies. Furthermore, the inser-tion loss and isolation are 0.3 dB and 20.2 dB at 2.6 GHz, and 0.9 dB and 24.5 dB at 3.3 GHz. The analysis and simulation results are corroborated by the measurements of the fabricated divider prototype. The competitive performance of the proposed circuit is also demonstrated through comparisons with state-of-the-art divider circuits from the literature.

  • Design and Microwave-Assisted Synthesis of TiO2-Lanthanides Systems and Evaluation of Photocatalytic Activity under UV-LED Light Irradiation
    • Adam Kubiak
    • Anna Grzegórska
    • Joanna Zembrzuska
    • Anna Zielińska-Jurek
    • Katarzyna Siwińska-Ciesielczyk
    • Marcin Janczarek
    • Piotr Krawczyk
    • Teofil Jesionowski
    2022 Pełny tekst Catalysts

    The TiO2-Eu and TiO2-La systems were successfully synthesized using the microwave method. Based on the results of X-ray diffraction analysis, it was found that regardless of the analyzed systems, two crystal structures were noted for the obtained samples: anatase and rutile. The analysis, such as XPS and EDS, proved that the doped lanthanum and europium nano-particles are present only on the TiO2 surface without disturbing the crystal lattice. In the synthesized systems, there were no significant changes in the bandgap energy. Moreover, all the obtained systems were characterized by high thermal stability. One of the key objectives of the work, and a scientific novelty, was the introduction of UV-LED lamps into the metronidazole photo-oxidation pathway. The results of the photo-oxidation study showed that the obtained TiO2 systems doped with selected lanthanides (Eu or La) show high efficiency in the removal of metronidazole, and at the same consuming nearly 10 times less electricity compared to conventional UV lamps (high-pressure mercury lamp). Liquid-chromatography mass-spectrometry (LC-MS) analysis of an intermediate solution showed the presence of fragments of the degraded molecule by m/z 114, 83, and 60, prompting the formulation of a plausible photodegradation pathway for metronidazole.

  • Design and Optimization of a Compact Planar Radiator for UWB Applications and Beyond
    • Michał Czyż
    • Jan Olencki
    • Adrian Bekasiewicz
    2022 Pełny tekst

    A compact monopole antenna for ultra-wideband (UWB) and beyond applications has been proposed. The radiator is based on the monopole topology. The super-wideband behavior has been achieved using a combination of spline-based modifications applied to the driven element, as well as utilization of a tapered feed and a slot-modified ground plane. The electrical performance of the structure has been tuned using a numerical optimization algorithm. The proposed design features reflection below the level of –10 dB within 2.8 GHz to 30 GHz range, as well as a footprint of only 404 mm2. The proposed structure has been compared in terms of bandwidth and size with the state-of-the-art antennas from the literature. The numerical results are supported by measurements of the fabricated antenna prototype.

  • Design and Optimization of Metamaterial-Based Dual-Band 28/38 GHz 5G MIMO Antenna with Modified Ground for Isolation and Bandwidth Improvement
    • Bashar Esmail
    • Sławomir Kozieł
    2022 IEEE Antennas and Wireless Propagation Letters

    This letter presents a high-isolation dual-band multiple-input multiple-output (MIMO) antenna based on the ground plane modification and optimized metamaterials (MMs) for 5G millimeter-wave applications. The antenna is a monopole providing a dual-band response at 5G 28/38 bands with a small physical size (4.8 × 2.9 × 0.762 mm3, excluding the feeding line). The MIMO consists of two symmetric radiating elements arranged adjacently with the mutual coupling of −19 dB and −17 dB at 28 and 38 GHz, respectively. Reducing the ground length enhances the isolation to 34.6 dB at 28 GHz, whereas embedding the MMs diminishes the coupling to −47 dB at 38 GHz. The trust-region gradient-based search algorithm is employed to optimize the MM structure dimensions and to enhance the isolation at 38 GHz. The MMs also contribute to the enhancement of bandwidth from 1.6 GHz to 1.7 GHz at 28 GHz (27.1–28.8 GHz) and from 2.75 GHz to 3.7 GHz at 38 GHz (35.2–38.9 GHz). The proposed system is capable of covering both 28/38 bands with low profile structure, high isolation, low envelope correlation coefficient (ECC) (< 0.210−4), and high diversity gain (DG) (> 9.99 dB). These properties demonstrate the system applicability for 5G millimeter-wave cellular communications.

  • Design of a Coplanar Waveguide-Fed Wideband Compact-Size Circularly Polarized Antenna and polarization-sense alteration
    • Ullah Ubaid
    • Sławomir Kozieł
    • Anna Pietrenko-Dąbrowska
    • Ismail Mabrouk
    2022 WIRELESS NETWORKS

    This paper presents the design and validation of a geometrically simple circularly polarized(CP) structure featuring flat gain in the sub-6 GHz 5th generation spectrum. The proposed structure is based on coplanar-waveguide-fed, modified wide slot etched in the ground plane. For generating CP waves, the coplanar ground planes are designed with slight asymmetry in both the horizontal and vertical directions. Furthermore, the ground plane at the back is modified to create an additional current component. The antenna is realized with a compact footprint of 0.36λo × 0.28λo (or 0.12o ). The operating frequency is from 2.5 to 6 GHz, which covers all the bands in the sub-6 GHz spectrum of the 5th generation technology. The impedance bandwidth of the antenna is in the range of 2.45 to 8 GHz and the axial ratio (AR) bandwidth is from 2.5 to 6 GHz, corresponding to more than 82% of relative bandwidth. The peak realized gain is 4 dBic, which is relatively high for a bidirectional wideband structure, and very stable throughout the entire operating band with a variation of ± 0.35 dBic. Unlike the design available in the literature (with asymmetrical ground planes), the proposed antenna has a consistent radiation pattern with a minor beam tilt. The design is fully optimized before prototyping and experimental validation. From the application viewpoint, the proposed antenna has the potential to be used in integrated systems. Moreover, a simple method for altering the sense of CP from right-hand CP (RHCP) to left-hand CP (LHCP) and vice versa is studied. This technique is useful for implementation of polarization diversity in the multiple-input-multipleoutput (MIMO) environment.

  • Design of Cost-Efficient Optical Fronthaul for 5G/6G Networks: An Optimization Perspective
    • Abdulhalim Fayad
    • Tibor Cinkler
    • Jacek Rak
    • Manish Jha
    2022 Pełny tekst SENSORS

    Currently, 5G and the forthcoming 6G mobile communication systems are the most promising cellular generations expected to beat the growing hunger for bandwidth and enable the fully connected world presented by the Internet of Everything (IoE). The cloud radio access network (CRAN) has been proposed as a promising architecture for meeting the needs and goals of 5G/6G (5G and beyond) networks. Nevertheless, the provisioning of cost-efficient connections between a large number of remote radio heads (RRHs) in the cell sites and the baseband unit (BBU) pool in the central location, known as the fronthaul, has emerged as a new challenge. Many wired and wireless solutions have been proposed to address this bottleneck. Specifically, optical technologies presented by passive optical networks (PONs) are introduced as the best suitable solution for 5G and beyond network fronthaul due to their properties of providing high capacity and low latency connections. We considered time and wavelength division multiplexed passive optical networks (TWDM-PONs) as a fronthaul for 5G and beyond. Taking that into consideration, in this paper, we propose an integer linear program (ILP) that results in the optimal optical fronthaul deployment while minimizing the total cost of 5G and beyond instances. However, for larger network instances, solving the ILP problem becomes unscalable and time-consuming. To address that, we developed two heuristic-based algorithms (the K-means clustering algorithm and the one based on the genetic algorithm—GA). We evaluated the suitability of our proposed ILP and heuristic algorithms in simulations by utilizing them to plan different network instances (dense and sparse).

  • Design of Microstrip UWB Balun Using Quasi-TEM Approach Aided by the Artificial Neural Network
    • Włodzimierz Zieniutycz
    • Łukasz Sorokosz
    2022 Progress in Electromagnetics Research Letters

    The design procedure for UWB balun realized in the microstrip technology is proposed in the paper. The procedure applies Artificial Neural Network which corrects the dimensions of the approximate design found by appropriate scaling of the dimensions of the prototype. The scale coefficients for longitudinal and transverse dimensions of microstrip lines are determined from electromagnetic modeling based on transmission line equations. The scaling procedure of radial stubs is also proposed. The design procedure was verified experimentally for exemplary balun with radial stub.

  • Design of residential buildings in architecture education
    • Antoni Taraszkiewicz
    • Karolina Taraszkiewicz
    2022 Pełny tekst World Transactions on Engineering and Technology Education

    This article is based on an analysis of residential building designs made by students of the Faculty of Architecture at Gdańsk University of Technology (FA-GUT), Poland, and on the results of a survey conducted among these students. The purpose of the survey was to verify the broad, interdisciplinary knowledge of the students required in preparation for taking up design issues, as well as their ability to use this knowledge in the design of residential buildings. When examining these issues, particular emphasis was placed on the possibility of creating methods of architectural education that would allow today’s students and future engineers to be appropriately trained, and thus become aware of the need to understand construction requirements, functional systems and their flexibility, principles of universal design and proxemics, economics of construction and use, energy efficiency and environmental protection, as well as psychological and spiritual needs of potential residents and other users. Respect for the context of the place also needs to be developed, and creative thinking and searching for architectural beauty encouraged and facilitated.

  • Design of three control algorithms for an averaging tank with variable filing
    • Michał Kolankowski
    • Robert Piotrowski
    2022 Pełny tekst Acta Mechanica et Automatica

    An averaging tank with variable filling is a nonlinear multidimensional system and can thus be considered a complex control sys-tem. General control objectives of such object include ensuring stability, zero steady state error and achieving simultaneously shortest possible settling time and minimal overshoot. The main purpose of this research work was the modelling and synthesis of three control systems for an averaging tank. In order to achieve the intended purpose, in the first step a mathematical model of the control system was derived. The model was adapted to the form required to design two out of three planned control systems by linearization and reduction of its dimensions, resulting in two system variants. A multivariable PID control system for the averaging tank was developed using optimization for tuning PID controllers. A state feedback and output feedback with integral action control (IC) system was designed using a linear-quadratic regulator (LQR) and optimization of weights. A fuzzy control system was de-signed using Mamdani inference system. The developed control systems were tested using Matlab environment. Finally, the simu-lation results for each control algorithm (and their variants) were compared and their performance was assessed, as well as the ef-fects of optimization in the case of PID and IC systems.

  • Design specification management with automated decision-making for reliable optimization of miniaturized microwave components
    • Sławomir Kozieł
    • Anna Pietrenko-Dąbrowska
    • Piotr Płotka
    2022 Pełny tekst Scientific Reports

    The employment of numerical optimization techniques for parameter tuning of microwave components has nowadays become a commonplace. In pursuit of reliability, it is most often carried out at the level of full-wave electromagnetic (EM) simulation models, incurring considerable computational expenses. In the case of miniaturized microstrip circuits, densely arranged layouts with strong cross-coupling effects make EM-driven tuning imperative to achieve the optimum performance. The process is even more challenging due to a typically large number of geometry parameters, and the lack of reasonable initial designs. The latter often encourages the use of global search procedures, which may be prohibitively expensive. In this paper, a novel automated framework for reliable optimization of miniaturized microwave components is proposed. Our methodology is based on design specification management, where the performance requirements imposed on the system are temporarily relaxed if the current design is unlikely to be improved (e.g., due to being away from the target operating frequency). The specifications are re-adjusted at each iteration of the algorithm, and eventually converge to their original values. Using two examples of compact microstrip couplers and a power divider, the presented technique is demonstrated to significantly improve the efficacy of local search routines under challenging design scenarios.

  • Design, synthesis and biological evaluation of novel N-phosphorylated and O-phosphorylated tacrine derivatives as potential drugs against Alzheimer’s disease
    • Maja Przybyłowska
    • Krystyna Dzierzbicka
    • Kowalski Szymon
    • Sebastian Demkowicz
    • Mateusz Daśko
    • Iwona Inkielewicz-Stępniak
    2022 Pełny tekst JOURNAL OF ENZYME INHIBITION AND MEDICINAL CHEMISTRY

    In this work, we designed, synthesised and biologically investigated a novel series of 14N- and O-phosphorylated tacrine derivatives as potential anti-Alzheimer’s disease agents. In the reaction of 9-chlorotacrine and corresponding diamines/aminoalkylalcohol we obtained diamino and aminoalkylhydroxy tacrine derivatives. Next, the compounds were acid to give final products 6–13 and 16–21 that were characterised by 1H, 13 C, 31P NMR and MS. The results of the docking studies revealed that the designed phosphorus hybrids, in theory can bind to AChE and BChE. All compounds exhibited significantly lower AutoDock Vina scores compared to tacrine. The inhibitory potency evaluation was performed using the Ellman’s method. The most inhibitory activity against AChE exhibited compound 8 with an IC50 value of 6.11nM and against BChE 13 with an IC50 value of 1.97 nM and they were 6- and 12-fold potent than tacrine. Compound 19 showed the lack of hepatocytotoxicity in MTT assay.

  • Design, synthesis, and biological evaluation of tetrahydroquinolinones and tetrahydroquinolines with anticancer activity
    • Małgorzata Ryczkowska
    • Natalia Maciejewska
    • Mateusz Olszewski
    • Milena Witkowska
    • Sławomir Makowiec
    2022 Pełny tekst Scientific Reports

    Colorectal cancer (CRC) is the most commonly diagnosed cancer in Europe and the United States and the second leading cause of cancer related mortality. A therapeutic strategy used for the treatment of CRC involves targeting the intracellular levels of reactive oxygen species (ROS). In this study, we synthesized a series of novel tetrahydroquinolinones and assessed their ability to inhibit CRC growth and proliferation by evoking cellular stress through ROS. Our results revealed that (2-oxo-4-phenyl- 5,6,7,8-tetrahydroquinolin-8-yl) N-(3-fluorophenyl)carbamate (20d) exhibited in vitro antiproliferative activity at micromolar concentrations. The compound also suppressed colony formation and the migration of HCT-116 cells, as well as deregulated the expression of several proteins involved in cell proliferation and metastasis. Furthermore, 20d induced massive oxidative stress by disrupting the balance of cells survival resulting in autophagy via the PI3K/AKT/mTOR signaling pathway. These findings suggest that this tetrahydroquinolinone can be an ideal lead compound for drug discovery based on quinone derivatives.

  • Desulfurization of raw naphtha cuts using hybrid systems based on acoustic cavitation and advanced oxidation processes (AOPs)
    • Elvana Cako
    • Reza Darvishi
    • Xun Sun
    • Grzegorz Boczkaj
    2022 Pełny tekst CHEMICAL ENGINEERING JOURNAL

    A combination of dual-frequency acoustic cavitation (acoustic cavitation) and UV assisted advanced oxidation processes (AOPs) reaction system was developed for desulfurization of raw naphtha used to produce aviation fuels. Various types of oxidants in hybrid systems including hydrogen peroxide, acetic acid, acetone, air and ozone were compared. At optimum oxidant to sulfur compounds molar ratio (rox) of 5.0, the hybrid process of acoustic cavitation /acetic acid/hydrogen peroxide (acoustic cavitation/peracetic acid) was the most effective treatment process with synergistic index of 7.55 and desulfurization efficiency of 100% (highest reaction rate constant of 0.1337 min-1) for all sulfur compounds present in naphtha within the short reaction time of 30 min. At rox of 0.5 and 1.0, the synergy coefficients of 3.77 and 5.41 corresponding to the desulfurization efficiencies of 93.07 and 95.10% were obtained in 180 min, respectively. Comparatively, at the rox of 5.0, the efficiency of acoustic cavitation combined with hydrogen peroxide alone and acetic acid alone was 63.68 and 47.36%, respectively. Alternative treatment process of acoustic cavitation /UV/acetone/water can be used for the complete desulfurization (100%) of specific sulphur compounds including dibutyl sulfide, di-tert butyl disulfide, 1,4-butanedithiol and benzyl thiol considering the optimum acetone to water ratio of 2:1. All acoustic cavitation-based treatment systems followed the pseudo first order kinetic model. The most expensive process was ozone-aided acoustic cavitation with treatment costs exceeding 100 USD m-3. The peracetic acid-based system was the most economic process with a treatment cost of 15 USD/m3 with electric energy consumption of 100.17 kWh/m3.

  • Detection and removal of priority substances and emerging pollutants from stormwater: case study of the Kołobrzeska collector, Gdańsk, Poland
    • Jakubowicz Paweł
    • Karolina Fitobór
    • Magdalena Gajewska
    • Małgorzata Drewnowska
    2022 Pełny tekst Sustainability

    Progressive urban development affects environmental balance and disrupts the hydrologic cycle, in which rainfall plays a significant role. Since rainwater is considered a valuable resource of the environment, many technical solutions are implemented that enable effective rainwater management. On the other hand, stormwater runoff from urban areas contains numerous (also toxic) substances, and therefore should be properly treated. In this study, a multistage constructed wetland (MCW) pilot installation was used to remove selected groups of priority substances and emerging pollutants from rainwater discharged from the urbanized catchment of the Kołobrzeska stormwater collector in Gdańsk, Poland. The obtained results show that rainwater runoff was characterized by a variable concentrations of heavy metals (Zn, Cd, Cu, Ni, Pb, Hg), polycyclic aromatic hydrocarbons (benzo(a)pyrene, benzo(b)fluoranthene, phenanthrene, fluoranthene and pyrene) and microplastics. Depending on the hydraulic load of the bed, the reduction efficiency for heavy metals ranged from 26.19 to 100%, and for microplastics from 77.16 to 100%, whereas for polycyclic aromatic hydrocarbons it was consistently high, and equaled 100%.