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Gdańsk University of Technology

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  • pt. „PRZYSTANEK OD ZGIEŁKU MIASTA # Gdańsk-Letnica”
    • Agnieszka Kurkowska
    2022

    plakat promujący wystawę pt. „PRZYSTANEK OD ZGIEŁKU MIASTA # Gdańsk-Letnica” w mediach społecznościowych oraz fizycznie w siedzibie GAK Gama w Gdańsku-Letnicy

  • Public Finance in Poland in a COVID Fog: A Look Through the Lens of Fiscal Transparency and Accountability
    • Maria Jastrzębska
    2022 Full text Studies in Logic, Grammar and Rhetoric

    Abstract. Goal– The aim of the article is to identify dysfunctional phenomena (implementation of specific mechanisms/solutions and actions taken), generating increased opacity and limit the responsibility/accountability of public f inance in Poland, exacerbated by the COVID-19 crisis. Methods– descriptive analysis, comparative analysis and financial analysis methods were used. Results– fiscal transparency and accountability in Poland is limited by: the marginalisation of the role of the state budget, the loosening of the stabilising expenditure rule, the creation of financial mechanisms based on special funds fed by repayable financing sources for the implementation of state tasks, inter alia, in the fight against the effects of the COVID-19 crisis, the use of national and EU methodologies for calculating the deficit and debt of the public sector in order to conceal part of them, the lack of a consolidated financial statement of the public finance sector.

  • Pure cross-anisotropy for geotechnical elastic potentials
    • Andrzej Niemunis
    • Katarzyna Staszewska
    2022 Full text Acta Geotechnica

    The pure cross-anisotropy is understood as a special scaling of strain (or stress). The scaled tensor is used as an argument in the elastic stiffness (or compliance). Such anisotropy can be overlaid on the top of any elastic stiffness, in particular on one obtained from an elastic potential with its own stress-induced anisotropy. This superposition does not violate the Second Law. The method can be also applied to other functions like plastic potentials or yield surfaces, wherever some cross-anisotropy is desired. The pure cross-anisotropy is described by the sedimentation vector and at most two constants. Scaling with more than two purely anisotropic constants is shown impossible. The formulation was compared with experiments and alternative approaches. Static and dynamic calibration of the pure anisotropy is also discussed. Graphic representation of stiffness with the popular response envelopes requires some enhancement for anisotropy. Several examples are presented. All derivations and examples were accomplished using the algebra program Mathematica.

  • Pursuing Analytically the Influence of Hearing Aid Use on Auditory Perception in Various Acoustic Situations
    • Piotr Szymański
    • Tomasz Poremski
    • Bożena Kostek
    2022 Full text Vibrations in Physical Systems

    The paper presents the development of a method for assessing auditory perception and the effectiveness of applying hearing aids for hard-of-hearing people during short-term (up to 7 days) and longer-term (up to 3 months) use. The method consists of a survey based on the APHAB questionnaire. Additional criteria such as the degree of hearing loss, technological level of hearing aids used, as well as the user experience are taken into consideration. A web-based application is developed, allowing answering the survey questions from any computer with Internet access. The results of the benefit obtained from the use of hearing aids in various acoustic environments, taking into account the time of their use, are presented and compared to the earlier outcomes. The research results show that in the first period of use of hearing aids, speech perception improves, especially in noisy environments. The perception of unpleasant sounds also increases, which may lead to deterioration of hearing aid acceptance by their users.

  • Pursuing Listeners’ Perceptual Response in Audio-Visual Interactions - Headphones vs Loudspeakers: A Case Study
    • Bartłomiej Mróz
    • Bożena Kostek
    2022 Full text Archives of Acoustics

    This study investigates listeners’ perceptual responses in audio-visual interactions concerning binaural spatial audio. Audio stimuli are coupled with or without visual cues to the listeners. The subjective test participants are tasked to indicate the direction of the incoming sound while listening to the audio stimulus via loudspeakers or headphones with the head-related transfer function (HRTF) plugin. First, the methodology assumptions and the experimental setup are described to the participants. Then, the results are presented and analysed using statistical methods. The results indicate that the headphone trials showed much higher perceptual ambiguity for the listeners than when the sound is delivered via loudspeakers. The influence of the visual modality dominates the audio-visual evaluation when loudspeaker playback is employed. Moreover, when the visual stimulus is present, the headphone playback pattern of behavior is not always in response to the loudspeaker playback.

  • Pursuing the Deep-Learning-Based Classification of Exposed and Imagined Colors from EEG
    • Alejandro A. Torres-García
    • Jesus Garcia Salinas
    • Luis Villaseñor-Pineda
    2022 LECTURE NOTES IN COMPUTER SCIENCE

    EEG-based brain-computer interfaces are systems aiming to integrate disabled people into their environments. Nevertheless, their control could not be intuitive or depend on an active external stimulator to generate the responses for interacting with it. Targeting the second issue, a novel paradigm is explored in this paper, which depends on a passive stimulus by measuring the EEG responses of a subject to the primary colors (red, green, and blue). Particularly, we assess if a compact and feature-extraction-independent deep learning method (EEGNet) can effectively learn from these EEG responses. Our outcomes outperformed previous works focused on a dataset composed of EEG signals belonging to 7 subjects while seeing and imagining three primary colors. The method reaches an accuracy of 45% for exposed colors, 43% for imagined colors, and 35% for the six classes. Last, the experiments suggest that EEGNet learned to discover patterns in the EEG signals recorded for imagined and exposed colors, and for the six classes, too.

  • Pyrolysis Combined with the Dry Reforming of Waste Plastics as a Potential Method for Resource Recovery—A Review of Process Parameters and Catalysts
    • Ewelina Pawelczyk
    • Izabela Wysocka
    • Jacek Gębicki
    2022 Full text Catalysts

    : Emissions of greenhouse gases and growing amounts of waste plastic are serious environmental threats that need urgent attention. The current methods dedicated to waste plastic recycling are still insufficient and it is necessary to search for new technologies for waste plastic management. The pyrolysis-catalytic dry reforming (PCDR) of waste plastic is a promising pro-environmental way employed for the reduction of both CO2 and waste plastic remains. PCDR allows for resource recovery, converting carbon dioxide and waste plastics into synthetic gas. The development and optimization of this technology for the high yield of high-quality synthesis gas generation requires the full understanding of the complex influence of the process parameters on efficiency and selectivity. In this regard, this review summarizes the recent findings in the field. The effect of process parameters as well as the type of catalyst and feedstock are reviewed and discussed.

  • Pyrolysis of RDF and Catalytic Decomposition of the Produced Tar in a Char Bed Secondary Reactor as an Efficient Source of Syngas
    • Bogusław Kusz
    • Dariusz Kardaś
    • Łukasz Heda
    • Bartosz Trawiński
    2022 Full text Processes

    One of the technical limitations of refuse-derived fuel (RDF) pyrolysis is the high content of tar in its gas products. In order to resolve this problem, a two-stage RDF pyrolysis with a catalyst based on char from RDF pyrolysis is proposed. This paper presents the results of municipal waste pyrolysis beginning in an oven heated to 480 °C and ending with catalytic tar cracking carried out in the temperature range from 800 to 1000 °C. Thermal and catalytic pyrolysis with a char catalyst containing a minimum of 6% Fe resulted in increases in the CO and H2 contents in gas products and decreases in CO2 and CH4. At 1000 °C, the mass ratio of gaseous products to liquids was greater than 6. The residence time of the gases in the catalytic zone was about 3–5 s. The reactor was a good source of hydrogen and carbon monoxide.

  • Pyrrole bearing diazocrowns: Selective chromoionophores for lead(II) optical sensing
    • Błażej Galiński
    • Ewa Wagner-Wysiecka
    2022 Full text SENSORS AND ACTUATORS B-CHEMICAL

    Diazocrowns of 18-, 21- and 23-membered rings with pyrrole residue as a part of macrocycle were for the first time used as chromoionophores in lead(II) selective optodes. Sensing properties of optodes depend on the type of macrocycle, namely its size and the type of linker: oligoether or hydrocarbon chain. The best results were obtained for optode bearing 18-membered crown with oligoether linker showing linear response range of 8.05 × 10−8–2.24 × 10−5 M lead(II) and detection limit of 1.15 × 10−8 M. Membrane, based on cellulose triacetate, is lead(II) selective giving color change from red to different shades of blue (pH 5.5). Results obtained for model and real samples of lead(II) showed that easily accessible and regenerable sensor material can be used for spectrophotometric and colorimetric (Digital Color Analysis) detection and determination of lead(II).

  • QoS Extensions for Flow-Awareness Networks
    • Sylwester Kaczmarek
    • Maciej Wolff
    2022 Full text International Journal of Electronics and Telecommunications

    The paper contains a description and research results of the proposal for distributed QoS extensions for Flow-Based Networking. These QoS extensions let the network accept or reject flows based on current network load and QoS promises for each of the flows. Proposed solution consists of two distributed components, each of them performing in every node, measurement system and access control. The solution could be applied in any network architecture that is able to distinguish flows and routers in this architecture contains flow state table. Proposed approach was verified by simulation, in FSA architecture. Verification was done for six different network structures servicing two traffic classes (MRS, ARS). The results of the simulation tests have confirmed that the average time delay and packet loss ratio in the network with proposed extensions are below thresholds and meet the requirements recommended by ITU-T.

  • QoS Resource Reservation Mechanisms for Switched Optical Networks
    • Sylwester Kaczmarek
    • Magdalena Młynarczuk
    • Arkadiusz Dumin
    2022

    The paper regards the problem of resource reservation mechanisms for Quality of Service support in switched optical networks. The authors propose modifications and extensions for resources reservation strategy algorithms with resources pools, link capacity threshold and adaptive advance reservation approach. They examine proposed solutions in Automatically Switched Optical Network with Generalized Multi-Protocol Label Switching named as ASON/GMPLS network. The analysis is performed by simulation the Polish network structure with the use of OMNeT++ discrete-event simulator.

  • QRS Morphology-Based EDR Signal—Factors Determining its Properties
    • Piotr Przystup
    • Artur Poliński
    • Jerzy Wtorek
    2022 Full text IEEE Access

    Respiration-induced signals contain a clinically significant information. It could be obtained utilizing both direct and indirect methods. ECG-Derived Respiration (EDR) method is the latter one. However, in this case, two approaches could be distinguished. First one is based on determining changes in the morphology of QRS complexes while the second one is based on the Respiratory Sinus Arrhythmia (RSA) mechanism. The former approach is discussed in the paper. The basic properties of QRS morphology-based EDR signal were evaluated by means of simulations performed using a developed FEM model and appropriate experiments. In effect, basing on changes of the leads’ voltages induced by a heart translation or rotation, or by both mechanisms undergoing simultaneously, the sensitivity-like surfaces and the synthetic EDR signals were obtained. A very good agreement of the experimental and simulation results was achieved. The QRS morphology-based signal’s properties strongly depend on geometrical relation of the used lead to dominating direction of the heart translation, its rotation, and on personal relation between these two mechanisms. The conclusions presented should be taken into account especially when developing or using QRS morphology-based approach in respiratory monitoring systems.

  • Qualia: About Personal Emotions Representing Temporal Form of Impressions - Implementation Hypothesis and Application Example
    • Zdzisław Kowalczuk
    • Michał Czubenko
    • Marlena Gruba
    2022

    The aim of this article is to present the new extension of the xEmotion system as a computerized emotional system, part of an Intelligent System of Decision making (ISD) that combines the theories of affective psychology and philosophy of mind. At the same time, the authors try to find a practical impulse or evidence for a general reflection on the treatment of emotions as transitional states, which at some point may lead to the emergence of new emotional qualities ascribed to phenomena (objects or events) perceived by the agent. Since there is a dispute in the literature about the meaning and usefulness of `private' emotions, the article attempts to present in a transparent and technical manner the problem of hypothetical qualia against the background of selected theories of emotions, taking into account the cultural aspect or division. By treating qualia as an expression of individual emotional diversity and learning capacity, qualia can be assigned a quite technical role in modeling the human mind and in implementing autonomous robots and agents.

  • Quality Analysis of Audio-Video Transmission in an OFDM-Based Communication System
    • Monika Zamłyńska
    • Grzegorz Debita
    • Przemysław Falkowski-Gilski
    2022

    Application of a reliable audio-video communication system, brings many advantages. With the spoken word we can exchange ideas, provide descriptive information, as well as aid to another person. With the availability of visual information one can monitor the surrounding, working environment, etc. As the amount of available bandwidth continues to shrink, researchers focus on novel types of transmission. Currently, orthogonal frequency division multiplexing (OFDM) is widely utilized both in wired and wireless transmission. In this paper we investigate the quality of service (QoS) parameters of a simulated data transmission system, dedicated particularly to audio and video content distribution with orthogonal frequency division multiplexing. The audio research part involves a group of four language sets, namely: American English, British English, German, and Polish, processed using the Ogg Vorbis format. Whereas, in the video part we investigate a set of MPEG-4 video sequences coded at standard resolution of 480 × 270 pixels. Tests were performed under varying network and bandwidth conditions, including signal-to-noise ratio (SNR) and bit error rate (BER). Results of this study may aid parties interested in designing additional backup or supplementary services for portable devices and user terminals, including reliable means of contact, surveillance and monitoring for the Industry 4.0 and Internet of things (IoT) concept.

  • Quality assessment of low voltage surge arresters
    • Leszek Litzbarski
    • Marek Olesz
    • Stanisław Wojtas
    • Michał Winiarski
    • Tomasz Klimczuk
    • Hubert Glowinski
    • Bartłomiej Andrzejewski
    2022 Full text IEEE Access

    Users expect reliable operation of the surge arrester during overvoltages, which may originate from a switching process or a lightning discharge. The necessary conditions to guarantee these expectations are: appropriate construction of the surge arrester, its production being maintained in accordance with technical standards, and a positive results of the type test (as well routine and acceptance tests). The recipient, especially when purchasing large quantities of the product, can check the final quality of the product through selective testing of samples from the market in order to find the best supplier. This manuscript specifies the basic parameters of low-voltage (LV) surge arresters of four manufacturers. Basic electrical parameters, i.e. leakage current and varistor voltage (U1mA) before and after the nominal discharge current (In) of 8 µs/20 µs, were determined for 10 randomly selected surge arresters of each manufacturer. Moreover one sample of each varistor batches was aged by fifty 8 µs/20 µs current impulses with In. The obtained results of structural analysis indicate that the crystal structure of the varistor materials changes after ageing process, affecting its electrical properties. The proposed research methodology can be employed as a basis for forecasting the stability of the arrester parameters under operating conditions.

  • Quality Control of Bacterial Extracellular Vesicles with Total Protein Content Assay, Nanoparticles Tracking Analysis, and Capillary Electrophoresis
    • Aleksandra Steć
    • Joanna Jońca
    • Krzysztof Waleron
    • Małgorzata Waleron
    • Agata Płoska
    • Leszek Kalinowski
    • Bartosz Wielgomas
    • Szymon Dziomba
    2022 Full text INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES

    Extracellular vesicles (EVs) were isolated from Pectobacterium zantedeschiae culturing media using direct ultracentrifugation (UC), iodixanol cushion ultracentrifugation (ICUC), and iodixanol density gradient ultracentrifugation (IDGUC) techniques. The isolates were characterized with total protein content assay (bicinchoninic acid assay, BCA), nanoparticles tracking analysis (NTA), and capillary electrophoresis (CE). A satisfactory correlation (R2 > 0.94) between quantitative results obtained with BCA, NTA and CE was achieved only for isolates obtained with the IDGUC. The correlation between protein content and CE was proved to be related to the isolates’ purity. The NTA was found unable to provide reliable information on EVs quantity in samples isolated with UC and ICUC, due to the co-isolated particulate impurities. Moreover, the work reports polysaccharides, used as culturing media components, as a potential source of bias of quantitation with total protein content assay and NTA. The study demonstrates the advantageous selectivity of CE in quality control of EVs and its ability to differentiate subpopulations of EVs of Pectobacterium.

  • Quality of Cryptocurrency Mining on Previous Generation NVIDIA GTX GPUs
    • Jerzy Demkowicz
    • Maciej Rutkowski
    • Przemysław Falkowski-Gilski
    2022

    Currently, there is a lot of previous generation NVIDIA GTX graphical processing units (GPUs) available on the market, which were ousted from by next-gen RTX units. Due to this fact, numerous fully-operational devices remain underused, which are available at an affordable price. First, this paper presents an analysis of the cryptocurrency market. Next, in this context, the results of research on the performance of NVIDIA graphics cards with dedicated software as a cryptocurrency mining platform. The research included three hardware platforms: GTX 480 x1, GTX 480 x2 and GTX 760 x1, tested under four cryptocurrencies, namely: Bitcoin, Litecoin, Monero and Ethereum. The custom-build test bench included power consumption as well as the efficiency of mining various digital currencies. Obtained results can aid any investigator interested in designing his own stand as well as configuring the environment.

  • Quantification of Compatibility Between Polymeric Excipients and Atenolol Using Principal Component Analysis and Hierarchical Cluster Analysis
    • Barbara Rojek
    • Maria Gazda
    • Marek Wesolowski
    2022 Full text AAPS PharmSciTech

    An important challenge to overcome in the solid dosage forms technology is the selection of the most biopharmaceutically efficient polymeric excipients. The excipients can be selected, among others, by compatibility studies since incompatibilities between ingredients of the drug formulations adversely affect their bioavailability, stability, efficacy, and safety. Therefore, new, fast, and reliable methods for detecting incompatibility are constantly being sought. Hence, the purpose of this work was to assess the usefulness of a heating, cooling, and reheating differential scanning calorimetry (DSC) program for detecting potential incompatibilities between atenolol, an active pharmaceutical ingredient (API), and polymeric excipients. Hot-stage microscopy (HSM), Fourier transform infrared (FTIR) spectroscopy, and powder X-ray diffraction (PXRD) were used as supporting techniques. Additionally, principal component analysis (PCA) and hierarchical cluster analysis (HCA) served as tools to support the interpretation of the data acquired from the DSC curves and FTIR spectra. As the alterations in the shape of the DSC peak of atenolol which are indicative of incompatibility are visible only on the cooling and reheating curves of the mixtures, the DSC heating–cooling–reheating program was found to be very useful for identifying potential incompatibilities in the binary mixtures of atenolol and polymeric excipients. The melting and recrystallization of atenolol alone and in its mixtures were also confirmed by HSM, while FTIR displayed changes in the spectra of mixtures due to incompatibility. These studies revealed that atenolol is incompatible with hydroxyethylcellulose, hypromellose, and methylcellulose. PXRD measurements at room temperature revealed that the crystallinity of atenolol did not change in these mixtures. However, its crystallinity was reduced in the mixtures previously heated up to 155 °C and then cooled to 25 °C.

  • Quantitative assessment of the influence of tensile softening of concrete in beams under bending by numerical simulations with XFEM and cohesive cracks
    • Ireneusz Marzec
    • Jerzy Bobiński
    2022 Full text Materials

    Results of the numerical simulations of the size effect phenomenon for concrete in comparison with experimental data are presented. In-plane geometrically similar notched and unnotched beams under three-point bending are analyzed. EXtended Finite Element Method (XFEM) with a cohesive softening law is used. Comprehensive parametric study with the respect to the tensile strength and the initial fracture energy is performed. Sensitivity of the results with respect to the material parameters and the specimen geometry is investigated. Three different softening laws are examined. First, a bilinear softening definition is utilized. Then, an exponential curve is taken. Finally, a rational Bezier curve is tested. An ambiguity in choosing material parameters and sof-tening curve definitions is discussed. Numerical results are compared with experimental out-comes recently reported in the literature. Two error measures are defined and used to quantita-tively assess calculated maximum forces (nominal strengths) in comparison with experimental values as a primary criterion. In addition, the force—displacement curves are also analyzed. It is shown that all softening curves produce results consistent with the experimental data. Moreover, with different softening laws assumed, different initial fracture energies should be taken to obtain proper results.

  • Quantum security and theory of decoherence
    • Piotr Mironowicz
    2022 Full text NEW JOURNAL OF PHYSICS

    We sketch a relation between two crucial, yet independent, fields in quantum information research, viz. quantum decoherence and quantum cryptography. We investigate here how the standard cryptographic assumption of shielded laboratory, stating that data generated by a secure quantum device remain private unless explicitly published, is disturbed by the einselection mechanism of quantum Darwinism explaining the measurement process by interaction with the external environment. We illustrate the idea with a paradigmatic example of a quantum random number generator compromised by a quantum analog of the Van Eck phreaking. In particular, we derive a trade-off relation between the eavesdropper's guessing probability $\mathrm{P}_{\mathrm{guess}}$ and the collective decoherence factor Γ of the simple form $\mathrm{P}_{\mathrm{guess}} + \Gamma \geqslant 1$.

  • Quasi-Static Response
    • James Underwood
    • Erick Alley
    • Jerolim Andric
    • Dario Boote
    • Zhen Gao
    • Ad Van Hoeve
    • Jasmin Jelovica
    • Yasumi Kawamura
    • Yooil Kim
    • Jianhu Liu
    • Sime Malenica
    • Heikki Remes
    • Asokendu Samanta
    • Krzysztof Wołoszyk
    • Deqing Yang
    2022 Full text

    Concern for the quasi-static response of ship and offshore structures, as required for safety and serviceability assessments. Attention shall be given to uncertainty quantification of quasi-static load and response analysis approaches, and their limitations, including exact and approximate methods for derivation of different acceptance criteria.

  • Ranking ecosystem services delivered by trees in urban and rural areas
    • Patrycja Przewoźna
    • Krzysztof Mączka
    • Marcin Mielewczyk
    • Adam Inglot
    • Piotr Matczak
    2022 Full text AMBIO

    Policies and strategies for tree management and protection on a national, regional, and local level have not sufficiently considered differences between rural and urban areas. We used expert knowledge to compare rural and urban areas in a case study evaluating the relative importance of ecosystem services (ES) in policy development. The Analytic Hierarchy Process (AHP) and focus group discussions were used to rank 17 ES, representing four classes of services: provisioning, regulating, habitat, and cultural. The results indicated that effective protection strategies, beyond simply increasing general tree cover, should consider specific benefits trees provide to local communities. We discuss the role of objective prioritization of ES delivered by trees in urban and rural areas and their consequences for decision-making processes.

  • Rapid Design Centering of Multi-Band Antennas Using Knowledge-Based Inverse Models and Response Features
    • Michał Kozieł
    • Sławomir Kozieł
    2022 KNOWLEDGE-BASED SYSTEMS

    Accounting for manufacturing tolerances as well as uncertainties concerning operating conditions and material parameters is one of the important yet often neglected aspects of antenna development. Appropriate quantification of uncertainties allows for estimating the fabrication yield but also to carry out robust design (e.g., yield maximization). For reliability reasons, statistical analysis should be executed at the accuracy level of full-wave electromagnetic (EM) simulation. Unfortunately, the associated computational cost is normally unmanageable when using traditional methods, e.g., Monte Carlo (MC) simulation, in a brute force manner. Computationally tractable approaches are based on surrogate modeling techniques, where the fast metamodel is either used to run MC at low cost, or to directly extract statistical moments of the system output (e.g., polynomial chaos expansion). The bottleneck of surrogate-based frameworks is a potentially large number of training data samples necessary to render the surrogate, which may become problematic especially for higher-dimensional parameter spaces. This paper proposes a novel approach to design centering of multi-band antennas, which involves knowledge-based inverse regression models constructed at the level of appropriately-defined response features. Our methodology capitalizes on establishing—in the form of the inverse model—a functional relationship between the feature point coordinates affecting satisfaction of the prescribed design specification and geometry parameters of the antenna under analysis. The inverse model predicts the parameter vectors featuring improved likelihood of fulfilling the requirements under uncertainties. Due to low-dimensionality of the feature space, only a handful of EM analyses is necessary to render the model, which translates into a low cost of the entire design centering procedure. The presented algorithm is demonstrated using three microstrip antennas and favorably compared to several benchmark methods.

  • Rapid on-line method of wastewater parameters estimation by electronic nose for control and operating wastewater treatment plants toward Green Deal implementation
    • Grzegorz Łagód
    • Jakub Drewnowski
    • Ł. Guz
    • Adam Piotrowicz
    • Zbigniew Suchorab
    • Małgorzata Drewnowska
    • Katarzyna Jaromin-Gleń
    • Bartosz Szeląg
    2022 Desalination and Water Treatment

    In order to comply with legal regulations related to wastewater quality, the operational mode of facilities at wastewater treatment plant (WWTP) should be properly adjusted according to parameters of influents, however it is very difficult without frequently performed measurements. Currently there are known many techniques and devices for assesment of wastewater parameters such as chemical oxygen demand, biochemical oxygen demand, total organic carbon, as well as phosphorus and nitrogen compounds. In spite of the far reaching improvements of treatment process automatisation, there still isn’t developed a automatic and fast measuring system of wastewater parameters. Rapid on-line method of wastewater parameters estimation by electronic nose and computer simulations could be recomended as an alternative solution in many WWTPs in comparation with traditional approch. Within this paper the analysis of real-time data obtained from laboratory bioreactor were used to estimate wastewater parameters in order to develop the inexpensive and fast-responding measuring for the WWTPs. The elaborated method enables continuous and relatively low cost monitoring of the wastewater quality even in many key points of operating and control WWTP. In this context, computer simulation support with on-line e-nose measurments could be cheap and useful tool to improve the WWTP efficiency.

  • Rapid Variable-Resolution Parameter Tuning of Antenna Structures Using Frequency-Based Regularization and Sparse Sensitivity Updates
    • Sławomir Kozieł
    • Anna Pietrenko-Dąbrowska
    2022 IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION

    Geometry parameter tuning is an inherent part of antenna design process. While most often performed in a local sense, it still entails considerable computational expenses when carried out at the level of full-wave electromagnetic (EM) simulation models. Moreover, the optimization outcome may be impaired if good initial design is not available. This paper proposes a novel approach to fast and improved-reliability gradient-based optimization of antenna structures. Our approach employs a frequency-based regularization to facilitate relocation of antenna operating parameters to their target values, which increases the chances of identifying a satisfactory design under challenging conditions (e.g., poor-quality starting point). At the same time, computational efficiency of the tuning process is enhanced through the involvement of variable-resolution EM models, and restricting the finite-differentiation sensitivity updates to selected parameters only. The latter are decided upon based on the analysis of the design relocation between the subsequent iterations of the optimization algorithm. The presented technique is validated using three examples of microstrip antennas optimized under different scenarios (matching improvement, gain enhancement, size reduction). The results demonstrate superior performance in terms of reliability and design quality as compared to conventional gradient-based and derivative-free search procedures. At the same time, a significant speedup is achieved over the frequency-regularization-based procedure not using the acceleration mechanisms.

  • Rapid Yield Optimization of Miniaturized Microwave Passives by Response Features and Variable-Fidelity EM Simulations
    • Anna Pietrenko-Dąbrowska
    • Sławomir Kozieł
    2022 Full text Scientific Reports

    The operation of high-frequency devices, including microwave passive components, can be impaired by fabrication tolerances but also incomplete knowledge concerning operating conditions (temperature, input power levels) and material parameters (e.g., substrate permittivity). Although the accuracy of manufacturing processes is always limited, the effects of parameter deviations can be accounted for in advance at the design phase through optimization of suitably selected statistical performance figures. Perhaps the most popular one is the yield, which provides a straightforward assessment of the likelihood of fulfilling performance conditions imposed upon the system given the assumed deviations of designable parameters. The latter are typically quantified by means of probability distributions pertinent to the fabrication process. The fundamental obstacle of the yield-driven design is its high computational cost. The primary mitigation approach nowadays is the employment of surrogate modeling methods. Yet, a construction of reliable metamodels becomes problematic for systems featuring a large number of degrees of freedom. Our work proposes a technique for fast yield optimization of microwave passives, which relies on response feature technology as well as variable-fidelity simulation models. Utilization of response features enables efficient handling of issues related to the system response nonlinearities. Meanwhile, the incorporation of variable-resolution simulations allows for accelerating the yield estimation process, which translates into remarkably low overall cost of the optimizing the yield. Our approach is verified with the use of three microstrip couplers. Comprehensive benchmarking demonstrates its superiority in terms of computational efficiency over the state-of-the-art algorithms, whereas reliability is corroborated by electromagnetic (EM)-driven Monte Carlo simulations.

  • "Raport z wstępnych badań własności stali trudnościeralnej 460HB",. ang "Report on preliminary tests of the properties of wear-resistant steel 460HB"
    • Wojciech Kiełczyński
    • Maria Głowacka
    • Lech Nadolny
    • Izydor Jóźwowski
    2022

    Mikrostrukturę badanej stali trudnościeralnej 460HB stanowi drobnoziarnisty martenzyt odpuszczony, który jest właściwy dla stali konstrukcyjnych niskowęglowych, niskostopowych ulepszonych cieplnie. W przypadku blach grubych, do których zalicza się badana stal, struktura może ulec zaburzeniu, jeżeli w hutniczym procesie wytwórczym wystąpiła niejednorodność odkształcenia plastycznego i w konsekwencji tworzenie się pasm segregacyjnych, jak w przypadku badanej stali. W badanej stali we występujących w strukturze obszarach jasnych pasm, zmierzona mikrotwardość HV0,05 jest znacząco większa w porównaniu do twardości w pasmach ciemnych- średnie wartości: 640 HV0,05 do 485 HV0,05..Powodem jest większy udział twardych węglików, powstałych podczas odpuszczania w pasmach jasnych. Pasmowy rozkład węglików wzdłuż kierunku walcowania jest przyczyną wydatnego obniżenia odporności stali na pękanie oraz niekorzystne zwiększenie anizotropii własności plastycznych blach, wyrażonej przez stosunek energii łamania próbek Charpy V poprzecznych do wzdłużnych, co ma istotne znaczenie podczas procesu spawania. Poziom udarności uzyskany wyniku łamania próbek w badaniach udarności jest nie do zaakceptowania.

  • Realizacja definiowanego programowo interfejsu radiowego NB-IoT
    • Olga Błaszkiewicz
    • Jarosław Magiera
    • Alicja Olejniczak
    • Piotr Rajchowski
    • Jarosław Sadowski
    • Jacek Stefański
    • Krzysztof Cwalina
    2022

    W niniejszym artykule przedstawiono sposób realizacji definiowanego programo-wo, uniwersalnego interfejsu radiowego do inteligentnych urządzeń IoT (Internet of Things) - DUCH IoT, pracującego zgodnie z międzynarodowymi standardami: LTE (Long Term Evolution) kat. NB1 (Narrowband) oraz LTE kat. NB2. Interfejs radiowy został za-implementowany w formie sprzętowo-programowego, frameworka z konfigurowalnym podziałem realizowanych funkcji pomiędzy częścią sprzętową (zrealizowaną jako moduły IP Core opisane w języku HDL (Hardware Description Language) w sposób niezależny od technologii) a częścią programową frameworka NB1/NB2 (zrealizowaną jako programowe moduły opracowane w języku C/C++), w zależności od możliwości obliczeniowych i za-sobów sprzętowych urządzenia IoT. Przedstawiono architekturę całego interfejsu wraz z modułową strukturą zaprojektowaną do przetwarzania stosu LTE NB-IoT.

  • Real-time monitoring of the emission of volatile organic compounds from polylactide 3D printing filaments
    • Wojciech Wojnowski
    • Kaja Kalinowska
    • Tomasz Majchrzak
    • Bożena Zabiegała
    2022 Full text SCIENCE OF THE TOTAL ENVIRONMENT

    Establishing the emission profile of volatile organic compounds generated during fused deposition modeling 3D printing using polymer filaments is important in terms of both understanding the processes taking place during thermal degradation of thermoplastics, and assessing the user's exposure to potentially harmful volatiles. However, obtaining detailed, real-time qualitative and quantitative results poses a challenge. In this paper solid-phase microextraction-gas chromatography-time-of-flight mass spectrometry and proton transfer reaction time-of-flight mass spectrometry were used to identify and monitor the emission of volatiles during thermal degradation of polylactide filaments and during 3D printing. Filaments of two different grades and three colours were used. It was possible to obtain detailed, time- and temperature-resolved emission profiles of the main products of thermal decomposition of lactide and polylactide 3D printing filaments at concentration levels of a few μg/g. This revealed different temperature-dependent emission characteristics of particular volatiles, such as, among others, lactide, acetaldehyde, acetic acid, and 2-butanone between various polylactide 3D printing filaments. This approach can be used to monitor the emission associated with printing with various other types of polymer 3D printing materials.

  • Real‐Time PPG Signal Conditioning with Long Short‐Term Memory (LSTM) Network for Wearable Devices
    • Marek Wójcikowski
    2022 Full text SENSORS

    This paper presents an algorithm for real‐time detection of the heart rate measured on a person’s wrist using a wearable device with a photoplethysmographic (PPG) sensor and accelerometer. The proposed algorithm consists of an appropriately trained LSTM network and the Time‐Domain Heart Rate (TDHR) algorithm for peak detection in the PPG waveform. The Long Short‐Term Memory (LSTM) network uses the signals from the accelerometer to improve the shape of the PPG input signal in a time domain that is distorted by body movements. Multiple variants of the LSTM network have been evaluated, including taking their complexity and computational cost into consideration. Adding the LSTM network caused additional computational effort, but the performance results of the whole algorithm are much better, outperforming the other algorithms from the literature.

  • Rearrangements of the nitrifiers population in an activated sludge system under decreasing solids retention times
    • Przemysław Kowal
    • Mohamad-Javad Mehrani
    • Dominika Sobotka
    • Sławomir Ciesielski
    • Jacek Mąkinia
    2022 Full text ENVIRONMENTAL RESEARCH

    Due to the key role of nitrite in novel nitrogen removal systems, nitrite oxidizing bacteria (NOB) have been receiving increasing attention. In this study, the coexistence and interactions of nitrifying bacteria were explored at decreasing solids retention times (SRTs). Four 5-week washout experiments were carried out in laboratory-scale (V=10 L) sequencing batch reactors (SBRs) with mixed liquor from two full-scale activated sludge systems (continuous flow vs SBR). During the experiments, the SRT was gradually reduced from the initial value of 4.0 d to approximately 1.0 d. The reactors were operated under limited dissolved oxygen conditions (set point of 0.6 mg O2/L) and two process temperatures: 12℃ (winter) and 20℃ (summer). At both temperatures, the progressive SRT reduction was inefficient for the out-selection of both canonical NOB and comammox Nitrospira. However, the dominant NOB switched from Nitrospira to Ca. Nitrotoga, whereas the dominant AOB was always Nitrosomonas. The results of this study are important for optimizing NOB suppression strategies in the novel N removal processes, which are based on nitrite accumulation.

  • Recent Advancements in Cyclodextrin-Based Adsorbents for the Removal of Hazardous Pollutants from Waters
    • Shan E Zehra Syeda
    • Dominika Nowacka
    • Muhammad Shahzeb Khan
    • Muhammad Khan
    • Anna Skwierawska
    2022 Full text Polymers

    Water is an essential substance for the survival on Earth of all living organisms. However, population growth has disturbed the natural phenomenon of living, due to industrial growth to meet ever expanding demands, and, hence, an exponential increase in environmental pollution has been reported in the last few decades. Moreover, water pollution has drawn major attention for its adverse effects on human health and the ecosystem. Various techniques have been used to treat wastewater, including biofiltration, activated sludge, membrane filtration, active oxidation process and adsorption. Among the mentioned, the last method is becoming very popular. Moreover, among the sorbents, those based on cyclodextrin have gained worldwide attention due to their excellent properties. This review article overviewed recent contributions related to the synthesis of Cyclodextrin (CD)-based adsorbents to treat wastewater, and their applications, especially for the removal of heavy metals, dyes, and organic pollutants (pharmaceuticals and endocrine disruptor chemicals). Furthermore, new adsorption trends and trials related to CD-based materials are also discussed regarding their regenerative potential. Finally, this review could be an inspiration for new research and could also anticipate future directions and challenges associated with CD-based adsorbents.

  • Recent advancements in LC‐MS based analysis of biotoxins: Present and future challenges
    • Debabrata Panda
    • Bisnu P. Dash
    • Sivakumar Manickam
    • Grzegorz Boczkaj
    2022 MASS SPECTROMETRY REVIEWS

    There has been a rising concern regarding the harmful impact of biotoxins, source of origin, and the determination of the specific type of toxin. With numerous reports on their extensive spread, biotoxins pose a critical challenge to figure out their parent groups, metabolites, and concentration. In that aspect, liquid chromatography‐mass spectrometry (LC‐MS) based analysis paves the way for its accurate identification and quantification. The biotoxins are ideally categorized as phytotoxins, mycotoxins, shellfish‐toxins, ciguatoxins, cyanotoxins, and bacterial toxins such as tetrodotoxins. Considering the diverse nature of biotoxins, both low‐resolution mass spectrometry (LRMS) and high‐resolution mass spectrometry (HRMS) methods have been implemented for their detection. The sample preparation strategy for complex matrix usually includes “QuEChERS” extraction or solid‐phase extraction coupled with homogenization and centrifugation. For targeted analysis of biotoxins, the LRMS consisting of a tandem mass spectrometer operating in multiple reaction monitoring mode has been widely implemented. With the help of the reference standard, most of the toxins were accurately quantified. At the same time, the suspect screening and nontarget screening approach are facilitated by the HRMS platforms during the absence of reference standards. Significant progress has also been made in sampling device employment, utilizing novel sample preparation strategies, synthesizing toxin standards, employing hybrid MS platforms, and the associated data interpretation. This critical review attempts to elucidate the progress in LC‐MS based analysis in the determination of biotoxins while pointing out major challenges and suggestions for future development.

  • Recent advances in aqueous virus removal technologies
    • Hussein Al-Hazmi
    • Hanieh Shokrani
    • Amirhossein Shokrani
    • Karam Jabbour
    • Otman Abida
    • Seyed Soroush Mousavi Khadem
    • Sajjad Habibzadeh
    • Shirish H. Sonawane
    • Mohammad Saeb
    • Adrián Bonilla-Petriciolet
    • Michael Badawi
    2022 CHEMOSPHERE

    The COVID-19 outbreak has triggered a massive research, but still urgent detection and treatment of this virus seems a public concern. The spread of viruses in aqueous environments underlined efficient virus treatment processes as a hot challenge. This review critically and comprehensively enables identifying and classifying advanced biochemical, membrane-based and disinfection processes for effective treatment of virus-contaminated water and wastewater. Understanding the functions of individual and combined/multi-stage processes in terms of manufacturing and economical parameters makes this contribution a different story from available review papers. Moreover, this review discusses challenges of combining biochemical, membrane and disinfection processes for synergistic treatment of viruses in order to reduce the dissemination of waterborne diseases. Certainly, the combination technologies are proactive in minimizing and restraining the outbreaks of the virus. It emphasizes the importance of health authorities to confront the outbreaks of unknown viruses in the future.

  • Recent Advances in Development of Waste-Based Polymer Materials: A Review
    • Krzysztof Formela
    • Maria Kurańska
    • Mateusz Barczewski
    2022 Full text Polymers

    Limited petroleum sources, suitable law regulations, and higher awareness within society has caused sustainable development of manufacturing and recycling of polymer blends and composites to be gaining increasing attention. This work aims to report recent advances in the manufacturing of environmentally friendly and low-cost polymer materials based on post-production and postconsumer wastes. Sustainable development of three groups of materials: wood polymer composites, polyurethane foams, and rubber recycling products were comprehensively described. Special attention was focused on examples of industrially applicable technologies developed in Poland over the last five years. Moreover, current trends and limitations in the future “green” development of waste-based polymer materials were also discussed.

  • Recent advances in hydrodynamic cavitation-based pretreatments of lignocellulosic biomass for valorization
    • Xun Sun
    • Shuai Liu
    • Xinyan Zhang
    • Yang Tao
    • Grzegorz Boczkaj
    • Joon Yong Yoon
    • Xiaoxu Xuan
    2022 BIORESOURCE TECHNOLOGY

    Recently, the hydrodynamic cavitation (HC)-based pretreatment has shown high effectiveness in laboratories and even in industrial productions for conversion of lignocellulosic biomass (LCB) into value-added products. The pretreatment capability derives from the extraordinary conditions of pressures at ∼500 bar, local hotspots with ∼5000 K, and oxidation (hydroxyl radicals) created by HC at room conditions. To promote this emerging technology, the present review summarizes the recent advances in the HC-based pretreatment of LCB. The principle of HC including the sonochemical effect and hydrodynamic cavitation reactor is introduced. The effectiveness of HC on the delignification of LCB as well as subsequent fermentation, paper production, and other applications is evaluated. Several key operational factors (i.e., reaction environment, duration, and feedstock characteristics) in HC pretreatments are discussed. The enhancement mechanism of HC including physical and chemical effects is analyzed. Finally, the perspectives on future research on the HC-based pretreatment technology are highlighted.

  • Recent advances on SOA formation in indoor air, fate and strategies for SOA characterization in indoor air - A review
    • Klaudia Pytel
    • Renata Marcinkowska
    • Małgorzata Rutkowska
    • Bożena Zabiegała
    2022 Full text SCIENCE OF THE TOTAL ENVIRONMENT

    Recent studies proves that indoor air chemistry differs in many aspects from atmospheric one. People send up to 90 % of their life indoors being exposed to pollutants present in gas, particle and solid phase. Particle phase indoor is composed of particles emitted from various sources, among which there is an indoor source – secondary chemical reactions leading to formation of secondary organic aerosol (SOA). Lately, researchers' attentions turned towards the ultrafine particles, for there are still a lot of gaps in knowledge concerning this field of study, while there is evidence of negative influence of ultrafine particles on human health. Presented review sums up current knowledge about secondary particle formation in indoor environment and development of analytical techniques applied to study those processes. The biggest concern today is studying ROS, for their lifetime in indoor air is very short due to reactions at the very beginning of terpene oxidation process. Another interesting aspect that is recently discovered is monoterpene autooxidation process that leads to HOMs formation that in turn can influence SOA formation yield. A complex studies covering gas phase and particle phase characterization, but also toxicological studies are crucial to fully understand indoor air chemistry leading to ultrafine particle formation.

  • Recent and Emerging Applications of Graphene-based metamaterials in Electromagnetics
    • Meisam Esfandiari
    • Ali Lalbakhsh
    • Paria Shehni
    • Saughar Jarchi
    • Mohsen Miab
    • Hamideh Mahtaj
    • Sam Reisenfeld
    • Mohammad Alibakhshikenari
    • Sławomir Kozieł
    • Stanisław Szczepański
    2022 Full text MATERIALS & DESIGN

    Surface Plasmon Polaritons (SPPs) operating in mid-infrared up to terahertz (THz) frequencies have been traditionally manufactured on expensive metals such as gold, silver, etc. However, such metals have poor surface confinement that limits the optical applications of SPPs. The invention of graphene is a breakthrough in plasmon-based devices in terms of design, fabrication and applications, thanks to its plasmonic wave distribution, low-cost prototyping and its inherent reconfigurability. In addition, recent advancements in plasmon-based metamaterials and metasurfaces led to the elimination of the past constraints on regular optical devices, opening a new door in THz devices and applications. This paper provides an operational perspective of the advanced graphene-based electromagnetic devices, with a focus on graphene enabled antennas, absorbers and sensors, analyzing the strengths and limitations of various design methodologies.

  • Recent Progress on Hydrogen Storage and Production Using Chemical Hydrogen Carriers
    • Ewelina Pawelczyk
    • Natalia Łukasik
    • Izabela Wysocka
    • Andrzej Rogala
    • Jacek Gębicki
    2022 Full text ENERGIES

    Depleting fossil fuel resources and anthropogenic climate changes are the reasons for the intensive development of new, sustainable technologies based on renewable energy sources. One of the most promising strategies is the utilization of hydrogen as an energy vector. However, the limiting issue for large-scale commercialization of hydrogen technologies is a safe, efficient, and economical method of gas storage. In industrial practice, hydrogen compression and liquefaction are currently applied; however, due to the required high pressure (30–70 MPa) and low temperature (−253 °C), both these methods are intensively energy consuming. Chemical hydrogen storage is a promising alternative as it offers safe storage of hydrogen-rich compounds under ambient conditions. Although many compounds serving as hydrogen carriers are considered, some of them do not have realistic perspectives for large-scale commercialization. In this review, the three most technologically advanced hydrogen carriers—dimethyl ether, methanol, and dibenzyltoluene—are discussed and compared. Their potential for industrial application in relation to the energy storage, transport, and mobility sectors is analyzed, taking into account technological and environmental aspects.

  • Recognition of Emotions in Speech Using Convolutional Neural Networks on Different Datasets
    • Marta Zielonka
    • Artur Piastowski
    • Andrzej Czyżewski
    • Paweł Nadachowski
    • Maksymilian Operlejn
    • Kamil Kaczor
    2022 Full text Electronics

    Artificial Neural Network (ANN) models, specifically Convolutional Neural Networks (CNN), were applied to extract emotions based on spectrograms and mel-spectrograms. This study uses spectrograms and mel-spectrograms to investigate which feature extraction method better represents emotions and how big the differences in efficiency are in this context. The conducted studies demonstrated that mel-spectrograms are a better-suited data type for training CNN-based speech emotion recognition (SER). The research experiments employed five popular datasets: Crowdsourced Emotional Multimodal Actors Dataset (CREMA-D), Ryerson Audio-Visual Database of Emotional Speech and Song (RAVDESS), Surrey Audio-Visual Expressed Emotion (SAVEE), Toronto Emotional Speech Set (TESS), and The Interactive Emotional Dyadic Motion Capture (IEMOCAP). Six different classes of emotions were used: happiness, anger, sadness, fear, disgust, and neutral. However, some experiments were prepared to recognize just four emotions due to the characteristics of the IEMOCAP dataset. A comparison of classification efficiency on different datasets and an attempt to develop a universal model trained using all datasets were also performed. This approach brought an accuracy of 55.89% when recognizing four emotions. The most accurate model for six emotion recognition was trained and achieved 57.42% accuracy on a combination of four datasets (CREMA-D, RAVDESS, SAVEE, TESS). What is more, another study was developed that demonstrated that improper data division for training and test sets significantly influences the test accuracy of CNNs. Therefore, the problem of inappropriate data division between the training and test sets, which affected the results of studies known from the literature, was addressed extensively. The performed experiments employed the popular ResNet18 architecture to demonstrate the reliability of the research results and to show that these problems are not unique to the custom CNN architecture proposed in experiments. Subsequently, the label correctness of the CREMA-D dataset was studied through the employment of a prepared questionnaire.

  • Recurrent Neural Network Based Adaptive Variable-Order Fractional PID Controller for Small Modular Reactor Thermal Power Control
    • Bartosz Puchalski
    • Tomasz Rutkowski
    • Jarosław Tarnawski
    • Tomasz Karla
    2022

    This paper presents the synthesis of an adaptive PID type controller in which the variable-order fractional operators are used. Due to the implementation difficulties of fractional order operators, both with a fixed and variable order, on digital control platforms caused by the requirement of infinite memory resources, the fractional operators that are part of the discussed controller were approximated by recurrent neural networks based on Gated Recurrent Unit cells. The study compares the performance of the proposed neural controller with other solutions, which are based on definitional fractional-order operators exploiting an infinite memory buffer and a classical adaptive PID controller. The proposed neural approximations of variable-order fractional operators applied to a PID-type controller provide a viable solution that can be successfully implemented on present-day digital control platforms. The research presented here focuses on the aspects of accuracy of approximators in simulated operating conditions within the thermal power control system of the challenging plant such as Small Modular Nuclear Reactor.

  • Redesigning Informal Beirut: Shaping the Sustainable Transformation Strategies
    • Piotr Lorens
    • Dorota Wojtowicz-Jankowska
    • Bahaa Bou Kalfouni
    2022 Full text Urban Planning

    Lebanon is distinguished by its strategic geographical location among the Arab countries. Beirut, as the capital city and the major commercial and cultural centre of the country, is a point of interest for migrants. The region has witnessed many changes since the end of World War II, which have resulted in internal and external conflicts, migrations, the centralization of the country’s economy, etc. Furthermore, the city has witnessed many periods of urbanization, destruction, reconstruction, and regeneration, which has contributed to the complex nature of the city’s population and a blurring of the boundaries between settlements which are quite different in their natures. As a result, Beirut has become a home to mixed communities and societies of different origins and natures. The extensive inflow of migrants combined with economic crises has contributed to the appearance of informal settlements. They are located in different areas of the city and its surroundings, known as Greater Beirut. These settlements face various challenges, including spatial organization, socioeconomic standing, and environmental concerns. The current situation in Lebanon (resulting from the Covid‐19 pandemic combined with the 4th of August 2020 blast in the port of Beirut) makes these challenges even more appalling. Some of the key issues discussed in this article are associated with the origin, current state, and prospects for improving the urban quality of these informal settlements considering their unplanned development and underused potentials. The article includes an inventory and speculates about the best possible strategies derived from three local interventions which are based on published reports. These examples represent rehabilitation and reconstruction activities in different cities in Lebanon. They can be applied to the specific situation of Beirut, given the variety of possible contexts there. The authors’ initial intention is to deal with the possible scope of the physical improvement in these settlements which will lead to socioeconomic and environmental development and will also include possible ways of reinventing Beirut’s urban structure

  • Reduced-cost optimization-based miniaturization of microwave passives by multi-resolution EM simulations for internet of things and space-limited applications
    • Anna Pietrenko-Dąbrowska
    • Sławomir Kozieł
    • Ali Raef
    2022 Full text Electronics

    Stringent performance specifications along with constraints imposed on physical dimensions, make the design of contemporary microwave components a truly onerous task. In recent years, the latter demand has been growing in importance, with the innovative application areas such as Internet of Things coming into play. The need to employ full-wave electromagnetic (EM) simu-lations for response evaluation, reliable yet CPU heavy, only aggravates the issue. This paper proposes a reduced-cost miniaturization algorithm that employs trust-region search procedure and multi-resolution EM simulations. In our approach, the resolution of the EM model is ad-justed throughout the optimization process based on its convergence status starting from the lowest admissible fidelity. As the algorithm converges, the resolution is increased up to the high-fidelity one, used at the final phase to ensure reliability. Four microwave components have been utilized as verification structures: an impedance matching transformer, and three branch-line couplers. Significant savings in terms of the number of EM analyses required to con-clude the size reduction process of 41, 42, 38 and 50 percent have been obtained (in comparison to a single-fidelity procedure). The footprint area of the designs optimized using the pro-posed approach are equal to: 32, 205, 410 and 132 mm2, in comparison to 52, 275, 525, and 213 mm2 of the initial (and already compact) design.

  • Reduced-Cost Two-Level Surrogate Antenna Modeling using Domain Confinement and Response Features
    • Anna Pietrenko-Dąbrowska
    • Sławomir Kozieł
    • Ullah Ubaid
    2022 Full text Scientific Reports

    Electromagnetic (EM) simulation tools have become indispensable in the design of contemporary antennas. Still, the major setback of EM-driven design is the associated computational overhead. This is because a single full-wave simulation may take from dozens of seconds up to several hours, thus, the cost of solving design tasks that involve multiple EM analyses may turn unmanageable. This is where faster system representations (surrogates) come into play. Replacing expensive EM-based evaluations by cheap yet accurate metamodels seems to be an attractive solution. Still, in antenna design, application of surrogate models is hindered by the curse of dimensionality. A practical workaround has been offered by the recently reported reference-design-free constrained modeling techniques that restrict the metamodel domain to the parameter space region encompassing high-quality designs. Therein, the domain is established using only a handful of EM-simulations. This paper proposes a novel modeling technique, which incorporates the response feature technology into the constrained modeling framework. Our methodology allows for rendering accurate surrogates using exceptionally small training data sets, at the expense of reducing the generality of the modeling procedure to antennas that exhibit consistent shape of input characteristics. The proposed technique can be employed in other fields that employ costly simulation models (e.g., mechanical or aerospace engineering).

  • Regeneration Project of Market Places GOSPOSTRATEG – “Polanki” Market in Gdańsk-Oliwa Pilot Project Monitoring Dataset
    • Justyna Borucka
    2022 Full text

    The dataset entitled Monitoring of activities carried out as part of prototyping and implementation of the pilot project in the area of the “Polanki” market and its direct neighbourhood, in the Gdańsk-Oliwa district, step1; stage from July 2020 year contains tabular monitoring lists (quantitative and qualitative documentation report in the form of tables) of activities carried out as part of the prototyping and implementation of the pilot project in the area of the Polanki market and its immediate vicinity in the Gdańsk-Oliwa district conducted during the month of July 2020. The data collection was carried out as part of the first step of monitoring in the series: “Monitoring of activities, prototyping and implementation of the pilot project in the area of the “Polanki” market, Gdańsk-Oliwa district, step1”. The second step of monitoring is scheduled for 2021. Monitoring is the basis for the subsequent analysis used in the implementation of the pilot project of the “Polanki” Market and supports the proper development of the regeneration project of the marketplace.

  • Regenerative Drug Discovery Using Ear Pinna Punch Wound Model in Mice
    • Paweł Sosnowski
    • Piotr Sass
    • Paulina Słonimska
    • Rafał Płatek
    • Jolanta Kamińska
    • Jakub Baczyński-Keller
    • Piotr Mucha
    • Grażyna Peszyńska-Sularz
    • Artur Czupryn
    • Michał Pikuła
    • Arkadiusz Piotrowski
    • Łukasz Janus
    • Sylwia Rodziewicz-Motowidło
    • Piotr Skowron
    • Paweł Sachadyn
    2022 Full text Pharmaceuticals

    The ear pinna is a complex tissue consisting of the dermis, cartilage, muscles, vessels, and nerves. Ear pinna healing is a model of regeneration in mammals. In some mammals, including rabbits, punch wounds in the ear pinna close spontaneously; in common-use laboratory mice, they remain for life. Agents inducing ear pinna healing are potential regenerative drugs. We tested the effects of selected bioactive agents on 2 mm ear pinna wound closure in BALB/c mice. Our previous research demonstrated that a DNA methyltransferase inhibitor, zebularine, remarkably induced ear pinna regeneration. Although experiments with two other demethylating agents, RG108 and hydralazine, were unsuccessful, a histone deacetylase inhibitor, valproic acid, was another epigenetic agent found to increase ear hole closure. In addition, we identified a pro-regenerative activity of 4-ketoretinoic acid, a retinoic acid metabolite. Attempts to counteract the regenerative effects of the demethylating agent zebularine, with folates as methyl donors, failed. Surprisingly, a high dose of methionine, another methyl donor, promoted ear hole closure. Moreover, we showed that the regenerated areas of ear pinna were supplied with nerve fibre networks and blood vessels. The ear punch model proved helpful in testing the pro-regenerative activities of small-molecule compounds and observations of peripheral nerve regeneration.

  • Regulation of LPS assembly via controlled proteolysis and sensing of LPS stress in Escherichia coli
    • Daria Biernacka
    2022 Full text

    Lipopolysaccharide (LPS) is a complex glycolipid, essential for the bacterial viability and along with phospholipids, it constitutes the major amphiphilic component of outer membrane (OM) in most of the Gram-negative bacteria, including Escherichia coli. LPS molecules confer an effective permeability barrier to the OM and play a crucial role in bacteria-environment and -host interactions. The synthesis and accumulation of this highly heterogeneous in the composition molecule are controlled by abundance of regulatory factors and growth conditions. Furthermore, the synthesis of LPS and phospholipids is tightly co-regulated and held at a nearly constant ratio. Any alterations in the balance of phospholipids and LPS are not tolerated by bacteria and cause cell death. This balance is achieved by tightly regulated turnover of unstable LpxC enzyme to maintain the flux of common precursor for the utilization in either LPS or phospholipid biosynthetic pathways. It constitutes an essential branch point in the biosynthesis of phospholipids and the lipid A part of LPS and simultaneously determines the first committed step in LPS biosynthetic pathway. It has been reported that LPS assembly requires the essential LapB protein to regulate FtsH-mediated proteolysis of LpxC protein. To further understand the function of LapB and its role in LpxC turnover, multicopy suppressor screening of ΔlapB was employed and it revealed a role for HslUV proteases in regulating LpxC amounts, providing the first alternative pathway of LpxC degradation. Isolation and characterization of an extragenic suppressor mutation that prevents lethality of ΔlapB by restoration of normal LPS synthesis identified a frame-shift in the essential gene designated lapC, suggesting LapB and LapC act antagonistically. The same lapC gene was identified during selection for mutations that induce transcription from LPS defects-responsive rpoEP3 promoter, confer sensitivity to LpxC inhibitor CHIR090 and exhibit a temperature-sensitive phenotype. Suppressors of lapC mutants that restored growth at elevated temperatures mapped to lapA/lapB, lpxC and ftsH genes. Such suppressor mutations restored normal levels of LPS and prevented excessive proteolysis of LpxC in lapC mutants. Interestingly, a lapC deletion could be constructed in strains either overproducing LpxC or in the absence of LapB, revealing that FtsH, LapB and LapC together regulate LPS synthesis by controlling LpxC amounts.

  • REJESTRACJA SERII ZDJĘĆ, Z WYMUSZENIEM ZMIENNYCH WARUNKÓW OŚWIETLENIOWYCH, JAKO TECHNIKI WSPOMAGAJĄCEJ PRZY AUTOMATYCZNYM ROZPOZNAWANIU TEKSTU
    • Grzegorz Jędrzejewski
    • Stanisław Galla
    2022 Elektronika : konstrukcje, technologie, zastosowania

    W artykule przedstawiono autorskie rozwiązania problemu wykonywania zdjęć niewyraźnych tekstów na opakowaniach i niewielkich produktach. W sytuacji gdy napis posiada niską rozdzielczość (drukarka atramentowa), albo jest wykonany poprzez technikę tłoczenia, wykonanie zwykłego, pojedynczego zdjęcia daje przeważnie niezadowalające wyniki. Dzięki przedstawionym tu rozwiązaniom, znacząco polepszamy materiał wejściowy (fotografie), który jest podstawą, na przykład do analizy przez algorytmy uczenia maszynowego, dedykowanych do rozpoznawania znaków (OCR).

  • Relations between magnetosonic perturbations as an indicator of a magnetosonic exciter and equilibrium parameters of a plasma
    • Anna Perelomova
    2022 Full text CONTRIBUTIONS TO PLASMA PHYSICS

    The thermodynamic relations between perturbation of pressure and pertur- bation of mass density and between components of velocity which specify a magnetosonic wave are theoretically studied. A planar flow with the wave vec- tor forming a constant angle with the equilibrium magnetic field is investigated. The theory considers deviation from the adiabaticity of a flow due to some kind of heating–cooling function and thermal conduction of a plasma. It considers also the weak impact of nonlinearity. The thermodynamic relations and corre- sponding diagrams reveal the hysteretic character of irreversible processes in a plasma flow and may indicate damping and nonlinear parameters of a flow. They may indicate also the geometry of a flow, the equilibrium parameters of plasma, and specify a magnetosonic source. The harmonic and impulsive exciters are discussed in this connection.

  • Relationship between Telomere Length, TERT Genetic Variability and TERT, TP53, SP1, MYC Gene Co-Expression in the Clinicopathological Profile of Breast Cancer
    • Marta Dratwa
    • Barbara Wysoczanska
    • Wioletta Brankiewicz
    • Martyna Stachowicz-Suhs
    • Joanna Wietrzyk
    • Rafał Matkowski
    • Marcin Ekiert
    • Jolanta Szelachowska
    • Adam Maciejczyk
    • Mariusz Szajewski
    • Maciej Bagiński
    • Katarzyna Bogunia-Kubik
    2022 Full text INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES

    The molecular mechanisms of telomerase reverse transcriptase (TERT) upregulation in breast cancer (BC) are complex. We compared genetic variability within TERT and telomere length with the clinical data of patients with BC. Additionally, we assessed the expression of the TERT, MYC, TP53 and SP1 genes in BC patients and in BC organoids (3D cell cultures obtained from breast cancer tissues). We observed the same correlation in the blood of BC patients and in BC organoids between the expression of TERT and TP53. Only in BC patients was a correlation found between the expression of the TERT and MYC genes and between TP53 and MYC. We found associations between TERT genotypes (rs2735940 and rs10069690) and TP53 expression and telomere length. BC patients with the TT genotype rs2735940 have a shorter telomere length, but patients with A allele rs10069690 have a longer telomere length. BC patients with a short allele VNTR-MNS16A showed higher expression of the SP1 and had a longer telomere. Our results bring new insight into the regulation of TERT, MYC, TP53 and SP1 gene expression related to TERT genetic variability and telomere length. Our study also showed for the first time a similar relationship in the expression of the above genes in BC patients and in BC organoids. These findings suggest that TERT genetic variability, expression and telomere length might be useful biomarkers for BC, but their prognostic value may vary depending on the clinical parameters of BC patients and tumor aggressiveness.