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  • Uncertainty quantification of modal parameter estimates obtained from subspace identification: An experimental validation on a laboratory test of a large-scale wind turbine blade
    • Szymon Greś
    • Riccardo Riva
    • Cem Yeniceli Süleyman
    • Palle Andersen
    • Marcin Łuczak
    2022 Pełny tekst ENGINEERING STRUCTURES

    The uncertainty afflicting modal parameter estimates stems from e.g., the finite data length, unknown, or partly measured inputs and the choice of the identification algorithm. Quantification of the related errors with the statistical Delta method is a recent tool, useful in many modern modal analysis applications e.g., damage diagnosis, reliability analysis, model calibration. In this paper, the Delta method-based uncertainty quantification methodology is validated for obtaining the uncertainty of the modal parameter and the modal indicator estimates in the context of several well-known subspace identification algorithms. The focus of this study is to validate the quality of each Delta method-based approximation with respect to the experimental Monte Carlo distributions of parameter estimates using a statistical distance measure. On top of that, the accuracy in obtaining the related confidence intervals is empirically assessed. The case study is based on data obtained from an extensive experimental campaign of a large scale wind turbine blade tested in a laboratory environment. The results confirm that the Delta method is, on average, adequate to characterize the distribution of the considered estimates solely based on the quantities obtained from one data set, validating the use of this statistical framework for uncertainty quantification in practice.

  • Unconventional and user-friendly sampling techniques of semi-volatile organic compounds present in an indoor environment: An approach to human exposure assessment
    • Mariusz Marć
    • Bożena Zabiegała
    2022 Pełny tekst TRAC-TRENDS IN ANALYTICAL CHEMISTRY

    The commonly applied solutions used to assess the potential risk of human exposure to semi-volatile organic compounds (SVOCs) are based on the investigation of biological samples collected in an invasive or non-invasive manner. For SVOCs, which are typically introduced to humans through the respiratory system, dermal adsorption, or digestive system, sampling solutions generally used in the indoor environments are classified as active and passive. From the user's perspective, the most convenient method to assess the potential risk is the use of an analytical tool that combines the benefits of passive and non-invasive sampling techniques—use of an unconventional personal sampler such as a silicone wristband, brooch, dog tag, cotton gauze, or viscose wiper. Despite the advantages of this method, the aforementioned techniques require further analytical research owing to the differences in the results of human exposure assessment owing to the lack of standards and unified sampling protocols.

  • Uncovering the invisible barriers to women’s success
    • Agnieszka Lendzion
    2022

    In the area of science and higher education, as in business and politics, the job situation of women is improving, and the percentage of women on executive positions is increasing. However, there is still a serious underrepresentation of women in the highest decision-making bodies. Ladies also take part in the strategic institutional events less frequently. There are still serious disproportions in academic and management positions, and the research career of women in relation to men slows down and encounters various barriers. Universities and research institutions undertake various bottom-up and top-down, voluntary and forced gender equality initiatives. Nevertheless, women still face the phenomena of the glass ceiling, glass escalator, discrimination, violent behavior, income inequality and other barriers on their career paths. What makes barriers and stereotypes still present in a well-educated, aware academic and research environment? What can we do to overcome these problems? How to introduce changes effectively so that women climb (not only the scientific) career levels with a similar and the same impetus as men, so that research teams and decision-making bodies become diverse? During the discussion panel dedicated to uncover the invisible barriers to women’s success, we will try to answer these questions, share good practices and discuss potential solutions supporting women in academic environment.

  • Understanding ion–ion and ion–solvent interactions in aqueous solutions of morpholinium ionic liquids with N-acetyl-L-alaninate anion through partial molar properties and molecular dynamics simulations
    • Dorota Warmińska
    • Maciej Śmiechowski
    2022 JOURNAL OF MOLECULAR LIQUIDS

    Amino acid ionic liquids (AAILs) provide a low toxicity, biodegradable alternative to conventional ionic liquids, while also maintaining solubility in water. Densities and sound velocities of aqueous solutions of four amino acid ionic liquids (AAILs), based on the N-alkyl-N-methylmorpholinium ([Mor1,R], R = 2, 3, 6, 8) cation and N-acetyl-L-alaninate ([N-Ac-L-Ala]) anion were measured at T = (293.15–313.15) K and at atmospheric pressure. These data were used to derive the apparent molar volumes and the apparent molar compressibilities in the concentration range of (0.02–0.3) mol kg−1. Established extrapolation procedures were applied to estimate the values of the limiting apparent molar volumes and the limiting apparent molar compressibilities. The limiting apparent molar expansibility coefficients were obtained and the hydration numbers for AAILs in aqueous solution were calculated using Passynski’s method. The results indicate that ion–solvent interactions in the studied solutions are determined by the hydrophobic effect and the charge effect, which are both dependent on temperature. At low temperatures the ion–solvent interactions are determined by the hydrophobic effect which results in the decrease of the limiting apparent molar compressibilities with an elongation of the alkyl chain of the cation of AAIL. At high temperatures the charge effect is dominant due to the decreasing limiting apparent molar compressibilities. On the other hand, ion–ion interactions are dominated by the hydrophobic effect regardless of the temperature. Molecular dynamics simulations were also performed and applied in interpretation of experimental data at atomistic detail. Computed limiting apparent molar volumes correlate well with the values derived from experiment. The apparent hydration volume, obtained by subtracting the intrinsic volume contribution, is large and positive, indicating hydrophobic hydration and not electrostriction is the principal mode of ions’ influence on the solvent. Analysis of radial distribution functions confirms insignificant share of ion–ion interactions via contact ion pairing. The solvation shells signify predominantly hydrophobic hydration, with locally strongly hydrated functional groups.

  • Understanding the early-stage release of volatile organic compounds from rapeseed oil during deep-frying of tubers by targeted and omics-inspired approaches using PTR-MS and gas chromatography
    • Tomasz Majchrzak
    • Mariusz Marć
    • Andrzej Wasik
    2022 Pełny tekst FOOD RESEARCH INTERNATIONAL

    During deep-frying, a plethora of volatile products is emitted with the fumes. These compounds could act as oil quality indicators and change the indoor air composition leading to health risks for occupants. The presented experiments focus on deep-frying of different tubers in rapeseed oil at different frying temperatures. Here, two scenarios for real-time monitoring of volatile organic compounds (VOCs) using proton transfer reaction mass spectrometry (PTR-MS) were proposed. The first, targeted, involved the application of gas chromatography with a flame ionization detector (GC-FID). The second, omics-inspired, involved the use of solid-phase microextraction (SPME) along with gas chromatography-mass spectrometry (GC-MS) and molecular networking algorithm as a complementary tool to the PTR-MS analysis. In a targeted approach, it was shown that the emission profile of pentanal and hexanal depends on the frying temperature and as the temperature increases, a sudden release of these compounds can be observed in the first minutes of frying. Meanwhile, using an omics-inspired protocol enables finding the relation between 1,4-heptadienal and 2-heptanone, octanal and limonene emissions. Using both approaches it was possible to record real-time changes in emission profiles of various oils’ degradation products. It was also observed that the emission profiles of VOCs are strictly related to the frying temperature and the type of fried tuber.

  • Understanding the Electronic Structure and Optical Properties of Vacancy-Ordered Double Perovskite A2BX6 for Optoelectronic Applications
    • Muhammad Faizan
    • Xinjiang Wang
    • Shaimaa A. M. Abdelmohsen
    • K. C. Bhamu
    • Subrahmanyam Sappati
    • Amel Laref
    • Nisar Muhammad
    • Muhammad Mushtaq
    • Ashraf M. M. Abdelbacki
    • Rabah Khenata
    2022 Pełny tekst ENERGY & FUELS

    Over the past few years, metal halide perovskite solar cells have made significant advances. Currently, the single-junction perovskite solar cells reach a conversion efficiency of 25.7%. Perovskite solar cells with a wide band gap can also be used as top absorber layers in multi-junction tandem solar cells. We examined the dynamical and thermal stability, electronic structure, and optical features of In2PtX 6 (X = Cl, Br, and I) perovskites, utilizing first-principle calculations. The stability is predicted using phonon dispersion spectrum and ab initio molecular dynamics simulation and also through the convex hull approach. The lattice constants and the optimized volume show an increasing trend with changing halide ions. The band structures computed for In2 PtCl6, In 2PtBr 6, and In2 PtI6 indicate their semiconducting nature with band gap values of 2.06, 2.01, and 1.35 eV, respectively. Halogens p and Pt d orbitals, respectively, play a prominent role in the formation of states around valence band maximum and conduction band minimum. The compounds, namely, In2PtBr 6 and In2PtI 6, exhibit high dielectric constants and small carrier effective masses. Furthermore, we found that In2 PtI 6 reveals a maximum theoretical efficiency owing to its optimum band gap and high optical absorption and is comparable to MAPbI3 in the studied range. Our results suggest that In 2PtX 6 (X = Cl, Br, and I) are suitable materials for single-junction and top absorber layers in tandem solar cells.

  • Underwater Processing of Materials
    • Dariusz Fydrych
    • Jacek Tomków
    2022 Pełny tekst Materials

    Editorial do SI

  • Underwater wet welding of S1300 ultra-high strength steel
    • Jacek Tomków
    • Michał Landowski
    • Dariusz Fydrych
    • Grzegorz Rogalski
    2022 Pełny tekst MARINE STRUCTURES

    Marine Structures Volume 81, January 2022, 103120 Underwater wet welding of S1300 ultra-high strength steel Author links open overlay panelJacekTomkówGrzegorzRogalski https://doi.org/10.1016/j.marstruc.2021.103120 Get rights and content Under a Creative Commons licenseopen access Highlights • Technological method of S1300 steel underwater weldability improving was proposed. • Number of cracks and hardness of welded joints was reduced by Temper Bead Welding (TBW). • Thickness of the base metal does not affect the effectiveness of the TBW technique. • The highest TBW effectiveness was found for 50% beads overlap. Abstract An expected tendency in marine and offshore structures is an increasing share of steels with high mechanical properties. The necessity to perform the welding work under water leads to a decreasing of the weldability of the steel. It results from the increased susceptibility to form cold cracks, especially in welded structures made of high-strength steel. A potential method, which may improve the problem of limited weldability of steel under water is the use of temper bead welding (TBW) technique. In this paper, the possibility of underwater wet welding by covered electrode S1300 ultra-high strength steel of different thickness (4 mm and 10 mm) has been investigated. The visual, metallographic macro- and microscopic tests, and Vickers HV10 measurements of samples with two nonparallel beads were performed. On the basis of the performed tests, the effectiveness of TBW technique was quantitatively verified. It was proved that TBW leads to positive microstructural changes and reduces the number of cracks in different regions of welded joints. Moreover, it was found that the proposed technique allows to decrease the hardness of S1300 steel joint by 30–80 HV10 in the weld metal and 40–100 HV10 in heat-affected zone. Finally, it was stated that the thickness of the base material does not affect the effectiveness of the TBW technique.

  • Universal construction of genuinely entangled subspaces of any size
    • Maciej Demianowicz
    2022 Pełny tekst Quantum Journal

    We put forward a simple construction of genuinely entangled subspaces – subspaces supporting only genuinely multipartite entangled states – of any permissible dimensionality for any number of parties and local dimensions. The method uses nonorthogonal product bases, which are built from totally nonsingular matrices with a certain structure. We give an explicit basis for the constructed subspaces. An immediate consequence of our result is the possibility of constructing in the general multiparty scenario genuinely multiparty entangled mixed states with ranks up to the maximal dimension of a genuinely entangled subspace.

  • Unusual divergence of magnetoacoustic beams
    • Anna Perelomova
    2022 Pełny tekst PHYSICS OF PLASMAS

    Two-dimensional magnetosonic beams directed along a line forming a constant angle h with the equilibrium straight magnetic field are considered. Perturbations in a plasma are described by the system of ideal magnetohydrodynamic equations. The dynamics of perturbations in a beam are different in the cases of fast and slow modes, and it is determined by h and equilibrium parameters of a plasma. In particular, a beam divergence may be unusual in the case of parallel propagation (h ¼ 0). Diffraction is more pronounced in the case of parallel propagation as compared to a flow without magnetic field, and less manifested in the case of perpendicular propagation. The beams propagating oblique to the magnetic field do not reveal diffraction. The dynamics of perturbations in a beam are analytically described in the cases of weak and strong nonlinearity compared to diffraction. Small magnitude perturbations at the axis of a beam in unusual cases propagate slower than that in the plane wave. Involving of thermal conduction leads to the coupling equations describing thermal self-action of a beam, which behaves differently in the ordinary and unusual cases. Self-focusing may occur in the presence of a magnetic field instead of conventional defocusing in gases

  • Up-to-date strategies and future trends towards the extraction and purification of Capsaicin: A comprehensive review
    • Roberto Castro-Muñoz
    • Emilia Gontarek-Castro
    • Seid Mahdi Jafari
    2022 Pełny tekst TRENDS IN FOOD SCIENCE & TECHNOLOGY

    Background According to the current need of manufacturing healthier products, food companies are seeking specific biomolecules that may offer additional added value (i.e., biological activities) to the new food formulations. Capsaicin, as the pungent ingredient of chili peppers, has become so far one of the target biomolecules explored since the 1950s. There is evidence demonstrating that capsaicin exhibits important biological properties in human health including inhibits acid secretion, stimulates alkali and mucus secretion and particularly gastric mucosal blood flow contributing to the prevention and healing of gastric ulcers, thermoregulation, among many other reported bioactivities. Scope and approach However, one of the main bottlenecks deals with the proper protocol of extraction and purification of this compound since most of the conventional methods based on solvent extraction do not provide efficient yield, along with diminished bioactivity of the compounds. Therefore, this review comprehensively elucidates the current strategies proposed by researchers towards the sustainable extraction and purification of capsaicin from its natural source, and comparison over traditional extraction methods. Particular emphasis has been focused on the innovative extraction techniques and the relevant insights over the last five years. Key findings and conclusion A detailed discussion is provided on the advantages and drawbacks of the novel techniques, key interactions with target molecules and their effect on the bioactivity of capsaicin. To finalize, according to the findings of this review, the future trends, perspectives, and research gaps are also given.

  • Urinary Tract Infections Caused by K. pneumoniae in Kidney Transplant Recipients – Epidemiology, Virulence and Antibiotic Resistance
    • Beata Krawczyk
    • Magdalena Wysocka
    • Michał Michalik
    • Justyna Gołębiewska
    2022 Pełny tekst FRONTIERS IN CELLULAR AND INFECTION MICROBIOLOGY

    Urinary tract infections are the most common complication in kidney transplant recipients, possibly resulting in the deterioration of a long-term kidney allograft function and an increased risk of recipient’s death. K. pneumoniae has emerged as one of the most prevalent etiologic agents in the context of recurrent urinary tract infections, especially with multidrug resistant strains. This paper discusses the epidemiology and risk factors associated with urinary tract infections in kidney transplant recipients, multi-drug resistance of K. pneumoniae (ESBL, KPC, NDM), treatment and pathogenesis of K. pneumoniae infections, and possible causes of recurrent UTIs. It also addresses the issue of colonization/becoming a carrier of K. pneumoniae in the gastrointestinal tract and asymptomatic bacteriuria in relation to a symptomatic UTI development and epidemiology.

  • Use of a wastewater recovery product (struvite) to enhance subtropical seagrass restoration
    • Conor Macdonnell
    • Franciszek Bydałek
    • T. Z. Osborne
    • A. Beard
    • S. Barbour
    • D. Leonard
    • Jacek Mąkinia
    • P.w. Inglett
    2022 Pełny tekst SCIENCE OF THE TOTAL ENVIRONMENT

    Seagrasses are in decline worldwide, and their restoration is relatively expensive and unsuccessful compared to other coastal systems. Fertilization can improve seagrass growth in restoration but can also release nutrients and pollute the surrounding ecosystem. A slow-release fertilizer may reduce excessive nutrient discharge while still providing resources to the seagrass's rhizosphere. In this study, struvite (magnesium ammonium phosphate), a relatively insoluble, sustainable compound harvested in wastewater treatment plants, was compared to Osmocote™ (14:14:14 Nitrogen: Phosphorus: Potassium, N:P:K), a popular polymer coated controlled release fertilizer commonly used in seagrass restoration. Two experiments compared the effectiveness of both fertilizers in a subtropical flow-through mesocosm setup. In the first experiment, single 0.5 mg of P per g dry weight (DW) doses of Osmocote™ and struvite fertilizers were added to seagrass plots. Seagrass shoot counts were significantly higher in plots fertilized with struvite than both the Osmocote™ and unfertilized controls (p < 0.0001). A significant difference in total P concentrations was observed in porewater samples of Osmocote™ vs struvite and controls (p < 0.0001), with struvite fertilized plots emitting more than controls (p ≤ 0.0001), but less than 2% of the total dissolved P (TDP) of Osmocote™ fertilized plots (100+ mg/L versus x > 5 mg/L). A subsequent experiment, using smaller doses (0.01 and 0.025 mg of P per gram DW added), also found that the struvite treatments performed better than Osmocote™, with 16–114% more aboveground biomass (10–60% higher total biomass) while releasing less N and P. These results indicate the relatively rapid dissolution of Osmocote™ may pose problems to restoration efforts, especially in concentrated doses and possibly leading to seagrass stress. In contrast, struvite may function as a slow-release fertilizer applicable in seagrass and other coastal restoration efforts.

  • Use of structural equation modeling in quantitative research in the field of management and economics: A bibliometric analysis in the systematic literature review
    • Agnieszka Zakrzewska-Bielawska
    • Anna Lis
    • Anna Ujwary-Gil
    2022 Pełny tekst Journal of Entrepreneurship, Management and Innovation

    PURPOSE: This paper aims to provide a comprehensive review of scholarly research focusing on using quantitative methods and particularly structural equation modeling (SEM) in management and economics studies, as well as provide a bibliometric agenda including the time horizon of individual publications, the highest citation rate, geographic and industry areas, methodological context, and keywords. METHODOLOGY: A systematic literature review (SLR) was undertaken using the Web of Science and Scopus databases. We limited our search to the last five years to identify the newest research publications, and we used keywords related to quantitative research while excluding qualitative research. Then we analyzed papers related to SEM and those published in English. FINDINGS: Our results confirmed that quantitative methods are used both in management and economics research, and showed a growing trend in the number of publications in the last five years. However, there are many more publications on management than on economics as well as there are more papers published in the Scopus database than Web of Science. Taking into account structural equation modeling, this method is used primarily in management research. In terms of industry, publications using SEM considered both single- and multi-industry including, first, all Asian countries and then African ones. Publications, especially in the management field, are descriptive in nature and based on primary data collected using a survey questionnaire. Papers are published in various journals and the most cited are those published in journals with wider subject areas. IMPLICATIONS: The systematic literature review is a fundamental necessity in any field of knowledge, benefiting both academia and learners. Our results may be useful for future researchers planning research using quantitative methods, especially SEM, in the business or economic field, by indicating the most cited papers and journals as well as industry and country areas. ORIGINALITY AND VALUE: This paper represents a systematic attempt to link quantitative methods, with a particular emphasis on SEM, with research interests on managerial and economic subjects and papers published in the Web of Science and Scopus databases. Employing the bibliometric analysis within the systematic literature review, the paper shows interest and the current state of research using quantitative methods which proves its value and originality.

  • User Mobility’s Influence on System Loss in Off-Body BAN Scenarios
    • Manuel M. Ferreira
    • Filipe D. Cardoso
    • Luis M. Correia
    • Sławomir Ambroziak
    • Kenan Turbić
    2022

    In this paper, a measurement campaign for off-body communications in an indoor environment is investigated for a set of on-body antennas. The channel impulse response was measured with the user approaching and departing from an off-body fixed antenna using two user dynamics: standing at fixed positions and walking. The processing of the measurement data allowed to evaluate system loss statistics. Different antenna configurations are classified in terms of mobility and visibility depending on on-body antenna placements. A dependence on distance is found for the antennas with the lowest mobility (chest and head), while no significant dependence is found for the antennas with highest mobility (arm and leg). Regarding the standard deviation for system loss, higher values are found in the walking scenarios (above 2.6 dB) compared to the standing ones (below 0.6 dB). Standard deviation also shows a clear dependence on mobility: 1.6 dB for walking and 0.5 dB for standing scenarios.

  • User-assisted methodology targeted for building structure interpretable QSPR models for boosting CO2 capture with ionic liquids
    • Joachim Eichenlaub
    • Paulina Rakowska
    • Adam Kloskowski
    2022 JOURNAL OF MOLECULAR LIQUIDS

    Task-specific ionic liquid (IL) is an emerging class of compounds that may be environmentally friendly. Properly selected, these compounds may be green alternative to amine solutions and can replace them in post-combustion carbon dioxide (CO2) capture processes on an industrial scale. However, owing to the vast diversity of ions and their possible combinations, laboratory research is time consuming and expensive. Therefore, computational methods are preferred for assessing their potential applications. In this study, three quantitative structure–property relationship models based on six distinct descriptors were created to predict Henry’s law constant (HLC) of CO2 in 62 ILs. The statistical parameters of multiple linear regression, logistic regression, and partial least squares models were satisfactory. In all cases, the coefficients of determination (R2) exceeded 0,90, and both external and internal validation proved them to be reliable and predictive with Q2 and Rpred2 values exceeding 0,90 and 0,87, respectively. Three of the descriptors were attributed to cations, and three were attributed to anions. In contrast to many other models, the descriptors were chosen in a manner that ensured their interpretability. Each of the six descriptors was analyzed for its influence on HLC. On this basis, guidelines for designing the structure of ionic liquids with increased CO2 absorption capacity were developed.

  • Using Convolutional Neural Networks for Corneal Arcus Detection Towards Familial Hypercholesterolemia Screening
    • Tomasz Kocejko
    • Jacek Rumiński
    • Magdalena Mazur-Milecka
    • Marzena Romanowska-Kocejko
    • Krzysztof Chlebus
    • Jo Kang-Hyun
    2022 Pełny tekst Journal of King Saud University-Computer and Information Sciences

    Familial hypercholesterolemia (FH) is a highly undiagnosed disease. Among FH patients, the onset of premature coronary artery disease is 13 times higher than in the general population. Early diagnosis and treatment is essential to prevent cardiovascular diseases and their complications, and to prolong life. One of the clinical criteria of FH is the occurrence of a corneal arcus (CA) among patients, especially those under 45 years old. Therefore, by detecting a CA, it might be possible to reduce the number of undiagnosed FH cases. In this paper, we propose using convolutional neural networks (CNN) for automatic recognition of the presence of a corneal arcus. To achieve this goal, we created a dataset of images of irises containing different stages of CA as well as irises without a CA. The core of the dataset consists of images acquired from patients with a corneal arcus, enroled in the National Centre of Familial Hypercholesterolemia in Gdansk. To increase the number of images, the dataset was complemented with images downloaded from the Internet. This dataset created for training and testing the model consisted of nearly 4000 images. To detect a CA in photographic images, we tested neural network models based on the VGG16, ResNet and Inception architectures. Finally, the performance of the models was evaluated on a set of images acquired from volunteers with a custom mobile application. The accuracy of CA detection in a real life scenario was 88% and the F1 score was 86%

  • Using differential pressure sensor to measure nitrous oxide level in a tank
    • Mateusz Czapski
    • Wiktor Lachowski
    • Natalia Balogh
    • Wojciech Deszczyński
    • Krzysztof Hucik
    • Wiktor Sieklicki
    2022 Pełny tekst

    A method for measuring the level of liquid nitrous oxide oxidizer in a hybrid rocket motor oxidizer tank is proposed. Presented approach is more accurate than the most commonly used method of this measurement, which employs weighting of the whole sounding rocket or an oxidizer tank. In our solution we use a differential pressure sensor to measure the change of pressure at the bottom of an oxidizer tank in comparison to the pressure of the gas phase above the liquid. Due to usage of a relatively short oxidizer tank, with height of 900 mm, and density of nitrous oxide being smaller than water, at 786.6 kg m3 , measured pressure differences are small, which requires high resolution of the sensor. Our system was prepared to work in a hybrid rocket motor of SimLE student organisation from Gdansk University of Technology (Gdansk, Poland). Developed propulsion system is designed to allow a sounding rocket with 4 kg of payload to accurately reach a flight altitude of 3000 m. The reason for accurate calculation of oxidizer amount in a tank is precise altitude planning for a sounding rocket launch which does not employ any active aerobraking system. For this flight strategy, accurate measurement of engine parameters is crucial. The described system is theoretically able to measure liquid level with a 5 mm resolution, which corresponds to roughly 50 g of nitrous oxide in the tank. Other approach, using a load cell, showed measurement resolution of 100 g of weight difference. This method was susceptible to hysteresis due to friction and other external conditions on a launch rail. Preliminary results from hybrid rocket engine tests are presented along with perspective for further method improvement.

  • Using Disparity Map for Moving Object Position Estimation in Pan Tilt Camera Images
    • Tomasz Kocejko
    • Jacek Rumiński
    • Jo Kang-Hyun
    2022

    In this paper we present the algorithm for rapid moving object position estimation in an images acquired from pan tilt camera. Detection of a moving object in a image acquired from a moving camera might be quite challenging. Standard methods that relay on analyzing two consecutive frames are not applicable due to the changing background. To overtake this problem we decided to evaluate the possibility of calculating a disparity map based on this consecutive images. As a result we were able to obtain approximate position of moving object in real time. Using cpu the average detection time was below 0.17 second.

  • Using Long-Short term Memory networks with Genetic Algorithm to predict engine condition
    • Semra Erpolat Tasabat
    • Olgun Aydin
    2022 Gazi University Journal of Science

    Predictive maintenance (PdM) is a type of approach for maintenance processes, allowing maintenance actions to be managed depending on the machine's current condition. Maintenance is therefore carried out before failures occur. The approach doesn’t only help avoid abrupt failures but also helps lower maintenance cost and provides possibilities to manufacturers to manage maintenance budgets in a more efficient way. A new deep neural network (DNN) architecture proposed in this study intends to bring a different approach to the predictive maintenance domain. There is an input layer in this architecture, a Long-Short term memory (LSTM) layer, a dropout layer (DO) followed by an LSTM layer, a hidden layer, and an output layer. The number of epochs used in the architecture and the batch size was determined using the Genetic Algorithm (GA). The activation function used after the output layer, DO ratio, and optimization algorithm optimizes loss function determined by using grid search (GS). This approach brings a different perspective to the literature for finding optimum parameters of LSTM. The neural network and hyperparameter optimization approach proposed in this study performs much better than existent studies regarding LSTM network usage for predictive maintenance purposes

  • Using Minimum Actuators to Control Shape and Stress of a Double Layer Spherical Model Under Gravity and Lateral Loadings
    • Najmadeen Saeed
    • Javad Katebi
    • Ahmed Manguri
    • Aram Mahmood
    • Marcin Szczepanski
    • Robert Jankowski
    2022 Pełny tekst Advances in Science and Technology Research Journal

    Spherical domes are picturesque structures built in developed countries to attract tourists. Due to horizontal and vertical overloading, the structures’ attractive shapes may be disturbed, and some members' stress may exceed the elastic level. In this paper, the shape and stress of a deformed double-layer spherical numerical model due to simultaneous lateral and vertical loadings are controlled, meanwhile, the number of actuators to alter the length of active members is minimized. The nodal displacements of the outer shape of the numerical model of the double-layer spherical structure are nullified. In addition, the stress of the members of the structure was monitored to stay within the elastic level. Moreover, the number of used actuators was minimized. These objectives are done by subjecting controlling formulations to a function that finds the minimum of constrained nonlinear multivariable which is called fmincon. The defined function in MATLAB uses one of the optimization algorithms (sequential quadratic programming, interior point, trust-region reflective, and active set). The algorithms search for active members that have a significant influence in controlling the targeted joints and members. Furthermore, the algorithms exclude the inactive actuators in several loops. The results obtained from MATLAB program are validated by SAP2000 software.

  • Using Synchronously Registered Biosignals Dataset for Teaching Basics of Medical Data Analysis – Case Study
    • Tomasz Kocejko
    2022 Pełny tekst

    Medical data analysis and processing strongly relies on the data quality itself. The correct data registration allows many unnecessary steps in data processing to be avoided. Moreover, it takes a certain amount of experience to acquire data that can produce replicable results. Because consistency is crucial in the teaching process, students have access to pre-recorded real data without the necessity of using additional equipment for data acquisition. The analyzed sample dataset consists of raw signals of ECG, Body Impedance and Body temperature recorded synchronously in laboratory conditions. The data are sampled with 250Hz sampling frequency and are framed in blocks. Students gain a chance to acquire, exchange and process the medical data in simulated conditions. Pre-recording data provides the opportunity to teach certain techniques that can be used in real life scenarios but in a control replicable environment.

  • Validated GC–MS method for determination of bisphenol a and its five analogues in dietary and nutritional supplements
    • Katarzyna Owczarek
    • Emilia Waraksa
    • Ewa Kłodzińska
    • Yaroslav Zrobok
    • Mariusz Ozimek
    • Dominik Rachoń
    • Błażej Kudłak
    • Andrzej Wasik
    • Zofia Mazerska
    2022 MICROCHEMICAL JOURNAL

    Bisphenol A (BPA) and its analogues showing structural and functional similarity to BPA are commonly applied in various industrial applications and thus are becoming ubiquitous in the environment. At the same time there is increasing scientific evidence that exposure to these chemicals may lead to adverse health effects in human and wildlife. In recent years dietary and nutritional supplements dedicated for athletes have become more popular and are widely used even by people who are not professionals. This study presents the development, optimization and validation of an analytical procedure for determination of six bisphenol analogues in dietary supplements using gas chromatography – mass spectrometry technique. All validation parameters met the established acceptance criteria in accordance with international guidelines.

  • Validating the Rules of Government Automation
    • Elsa Estevez
    • Tomasz Janowski
    • David Benjamin Roseth
    2022

    There is growing evidence on the benefits and risks of government automation, and how should government organizations proceed with automation when the benefits outweigh the risks. This evidence was recently consolidated into the "rules of government automation", part of the project funded by the Inter-American Development Bank. The project uncovered that the combined nature of government work and its transformation into digital government create many opportunities for automation. However, such opportunities can be only realized when the right automation technology becomes available and when government organizations are willing, capable, and authorized to introduce it, considering the impact on the organization and its stakeholders and the balance of benefits and risks brought about by this impact. The aim of the workshop is to validate the above “rules of government automation”. To this end, the participants will bring to the workshop their own government automation cases, from practice or research, establish thorough inspection and guided reasoning whether the rules hold for their cases, refine them otherwise, and iteratively agree on the refined rules across all cases. The workshop will also initiate the planning of a special issue of Government Information Quarterly to advance the theory and practice of government automation.

  • VALUATION OF EMBEDDED OPTIONS IN NON-MARKETABLE CALLABLE BONDS: A NEW NUMERICAL APPROACH
    • Roman Skalický
    • Marek Zinecker
    • Adam P. Balcerzak
    • Michał Pietrzak
    • Elżbieta Rogalska
    2022 Pełny tekst Technological and Economic Development of Economy

    The issue of how to price options embedded in callable bonds has attracted a lot of interest over the years. The usual bond valuation methods rely on yield curves, risk premium, and other parameters to estimate interest rates used in discounted cash flow calculations. The option to retire the bond is, however, neglected in the standard pricing models, causing a systematic overvaluation of callable bonds. In the event of a decline in interest rates, investors are exposed to the risk of a lower return on investment than indicated by the yield to maturity. We propose a novel approach to valuing the risk that the issuer will use the right to buy back the bond at a specific call price. While prior models are focused on valuing marketable callable bonds, we deliver a unique approach to valuing bonds with an embedded European option (or a multiple option) that are traded solely through private transactions. These can typically be characterized by the lack of historical records on transaction prices. The modular character of calculation we propose allows us to take into account additional information, such as probable behaviour of the issuer, available opportunities for achieving alternative earnings or different estimates in terms of interest rate development.

  • Variations in host surfaces morphology and biology of ciliate epibionts explaining distribution pattern of epibionts in the invasive signal crayfish Pacifastacus leniusculus (Dana, 1852)
    • A. Dobrzycka‐Krahel
    • L. Rolbiecki
    • Jakub Karczewski
    • Marcin Skóra
    2022 JOURNAL OF ZOOLOGY

    ciliates on the signal crayfish Pacifastacus leniusculus in relation to specialized structures of the host’s exoskeleton for the first time. This species is known to maintain a relatively clean carapace, but it is sometimes overgrown by other organisms. Epibionts cover different parts of the signal crayfish body, mainly antennae, antennules, maxillipedes III and pereiopods with inner edges of chelae; however, some parts of the signal crayfish are not fouled. e.g. dorsal surfaces of the carapace and dorsal surfaces of chelae. Using scanning electron microscopy (SEM), topographies of different parts of the crayfish’s exoskeleton were examined. Our investigations revealed that the epibiosis in the signal crayfish was determined by morphology of body surfaces. No epibionts were found on smooth surfaces with regular single setae (a known design that prevents fouling in aquatic environments). The dimpled surfaces with regular single micro-papillae may be considered as a newly described example of self-cleaning surfaces. Bio-inspired surface patterning presents promising approaches to the design of novel functional surfaces that can prevent biofouling. The new self-cleaning design may be used in further technological applications.

  • Vehicle Detection and Speed Estimation Using Millimetre Wave Radar
    • Piotr Odya
    2022 Pełny tekst

    The dataset titled Data from 76- to 81-GHz mmWave Sensor located at S7 road contains data recorded employing an IWR1642 mmWave sensor from Texas Instruments. The data comes from two sessions lasting 24h each. The dataset provides the possibility to perform analyses related to car traffic intensity on one of the carriageways of the motorway heading to the Gdańsk metropolitan area. Based on the gathered data, it is possible to calculate the number of vehicles in particular time intervals and to estimate their speed.

  • Verification and Benchmarking in MPA Coprocessor Design Process
    • Tomasz Stefański
    • Kamil Rudnicki
    • Wojciech Żebrowski
    2022

    This paper presents verification and benchmarking required for the development of a coprocessor digital circuit for integer multiple-precision arithmetic (MPA). Its code is developed, with the use of very high speed integrated circuit hardware description language (VHDL), as an intellectual property core. Therefore, it can be used by a final user within their own computing system based on field-programmable gate arrays (FPGAs). The coprocessor is still under development and its open-source code is available on the Internet, based on the Mozilla Public License. Therefore, verification and benchmarking of the coprocessor code are vitally important issues as the sources are continually downloaded by users all over the world. In this contribution, we present software tools developed as a part of the system, allowing for detection of errors in the coprocessor code as well as for execution of its benchmarking tests. The research conclusion is that, without well-designed verification and benchmarking software tools, the development of any advanced digital circuit, such as a coprocessor, is actually impossible in realistic time. It stems from the fact that 60% of the project repository include hardware-description codes, whereas the rest of the codes support correct development of the project, i.e., verification and benchmarking in the design process.

  • Verification of punching shear outside the shear cap by the direct method
    • Maciej Grabski
    • Andrzej Ambroziak
    2022 Pełny tekst Archives of Civil Engineering

    The proposition of a method to verify the punching resistance for very large supports based on the EN 1992-1-1 standard is described in this paper. The present standard guidelines for the calculation of the punching resistance for large supports are also summarised. The proposed direct method is compared with other standard methods using an example taken from design practice. This method consists of a direct check of the shear forces at specific locations of the control perimeter with the permissible shear force calculated from the EC2 standard. The method showed very good agreement with the experiment while remaining practical for applications. The method presented takes into account the actual distribution of shear forces in the vicinity of the support, taking into account the influence of non-uniform loads, irregular floor geometry, the concentration of internal forces at the corners of the support and the influence of the stiffness of the head used. The paper provides scientists, engineers, and designers new method (called the direct method) for estimation of the punching load-bearing capacity outside the shear cap.

  • Verification of Satellite Railway Track Position Measurements Making Use of Standard Co-Ordinate Determination Techniques
    • Jacek Szmagliński
    • Andrzej Wilk
    • Władysław Koc
    • Krzysztof Karwowski
    • Piotr Chrostowski
    • Jacek Skibicki
    • Sławomir Grulkowski
    • Sławomir Judek
    • Roksana Licow
    • Karolina Makowska-Jarosik
    • Michał Michna
    • Tadeusz Widerski
    2022 Pełny tekst Remote Sensing

    The article presents the results of satellite railway track position measurements performed by a multidisciplinary research team, the members of which represented Gdansk University of Technology and Gdynia Maritime University. Measuring methods are described which were used for reconstructing the railway track axis position and diagnosing railway track geometry deformations. As well as that, the description of the novel method developed by the authors to perform mobile GNSS measurements is included. The reported research aimed at assessing the uncertainty of railway track axis reconstruction making use of the dynamic GNSS method. To assess the applicability of this method, the obtained results were compared with those from the stationary measurement method used in railway business. The data used for comparison was recorded on the same railway track section during several measurement campaigns. In these campaigns, different types of GNSSs with different position recording frequencies (1–100 Hz) were used at different measurement speeds (5–70 km/h). The performed analysis has shown that the accuracy of railway track axis reconstruction making use of mobile GNSS measurements is sufficient for using this methodology in railway business.

  • Verification of the method of reconstructing convective velocity fields on the basis of temperature fields in vertical, differential and equally heated, open and closed channels
    • Krzysztof Tesch
    • Michał Ryms
    • Witold Lewandowski
    2022 Pełny tekst INTERNATIONAL JOURNAL OF HEAT AND MASS TRANSFER

    This paper describes a method of reconstructing velocity fields, i.e. a numerical reconstruction procedure (NRP) that involves the numerical processing of experimentally measured temperature distributions in free convection heat transfer. The NRP consists in solving only the continuity and Navier–Stokes equations with an additional source term. This term is proportional to a known temperature (e.g. from a thermal imaging camera) and replaces the Fourier–Kirchhoff equation, which also means that the NRP does not require boundary conditions associated with the temperature to be formulated. In order to verify the NRP, the experimental results of two published cases were taken into consideration. In the first case, the temperature and velocity distributions were determined during free convection heat transfer in a closed cavity, i.e. in a vertical channel formed between differentially heated plates. Subsequently, the velocity distributions obtained by the NRP were compared directly with the experimental results. However, in order to verify the correctness of this method for the entire field, not just for the individual locations, free convection heat transfer measurements in an open channel formed between two isothermal, equally heated plates were considered. A thermal imaging camera was used to detect the temperature field in air. In this case, verification of the NRP method required the results obtained in the form of a reconstructed velocity field to be compared with a field obtained using standard numerical calculations (SNC). Importantly, the NRP provides new opportunities for thermal imaging cameras equipped with a mesh for air temperature detection, for example, the visualisation of air velocity fields in free convective heat transfer.

  • Vernacular and low-tech technologies in humanitarian architecture on the example of Senegal
    • Robert Idem
    • Katarzyna Zielonko-Jung
    • Aleksandra Karpińska
    2022 Pełny tekst Architectus

    Humanitarian architecture belongs to the broader trend of socially engaged architecture, whose main goal is to introduce new values to the quality of life of particular communities. Specifically, humanitarian architecture deals with aid to poverty-stricken communities. The context of economic constraints poses a particular challenge to architects and builders. It is a matter of natural necessity to look for cheap, locally available materials and solutions that can be applied by unskilled labor. The above article discusses the applicability of native and low-tech technologies as basic con- struction methods for humanitarian architecture. The research focuses on Senegal, located in West Africa. The article aims to identify material and construction solutions in buildings related to humanitarian aid and social support on behalf of the local community, erected or designed in Senegal. An analysis of four examples in Senegal was conducted, namely, two implemented facilities and two planned ones. The basic criteria for the analysis were provided by the social purpose these objects serve, as well as by the materials and technologies applied. The conclusions concern the types and scope of vernacular and low-tech technologies applied, as well as the correlation between the analyzed objects’ design and construction and sustainable development

  • VI Sympozjum Historii Elektryki
    • Agnieszka Leszczewicz
    2022 Pełny tekst Pismo PG

    Sympozjum Historii Elektryki jest cykliczną konferencją organizowaną z inicjatywy Centralnej Komisji Historycznej Stowarzyszenia Elektryków Polskich, której celem jest upowszechnianie dorobku i historii oraz podkreślenie roli zasłużonych postaci dla rozwoju elektryki w Polsce. Pracownicy Politechniki Gdańskiej biorą udział w sympozjach od pierwszej edycji. VI Sympozjum Historii Elektryki w 2022 odbyło się w Katowicach i było głównym punktem jubileuszowych X Katowickich Dni Elektryki.

  • Vibration-Based Investigation of a Historic Bell Tower to Understand the Occurrence of Damage
    • Agnieszka Tomaszewska
    • Milena Drozdowska
    • Czesław Szymczak
    2022 International Journal of Architectural Heritage

    ABSTRACT The paper presents a survey of the historic Arch-cathedral bell tower in Vilnius induced by the appearance of cracks in the structure after a new bell system installation. An attempt is undertaken to identify the reason for the crack occurrence and to check a possible crack influence on global structural behaviour. The research is based on dynamic measurements made in the tower during ambient vibrations and during vibrations caused by swinging bells. The amplitudes of the accelerations and the spectral peaks due to the ambient and excited vibrations are compared. Magnification of the first spectral peak due to bells swinging points at resonance. The root-meansquare analysis is conducted to detect the tower section most vulnerable to swinging bells. The modal curvature approach applied to the first mode shape serves as the damage indicator. The algorithm locates damage in the region of the cracks observed in the tower; thus, the cracks are considered structural. The research proves the necessity of a dynamic survey in similar cases before important decisions are undertaken regarding the replacement of the bell system.

  • Video of LEGO Bricks on Conveyor Belt Dataset Series
    • Tomasz Boiński
    2022 Pełny tekst

    The dataset series titled Video of LEGO bricks on conveyor belt is composed of 14 datasets containing video recordings of a moving white conveyor belt. The recordings were created using a smartphone camera in Full HD resolution. The dataset allows for the preparation of data for neural network training, and building of a LEGO sorting machine that can help builders to organise their collections.

  • Virtual immersive environments
    • Jacek Lebiedź
    2022

    Yet a higher level of active systems may be achieved when users are fully immersed in an interface which is a 3D computer generated virtual world and can interact with surrounding objects of that world as they were in a real one. This is the issue covered by Chapter 7. Interaction in such a world is both multidimensional and multimodal, with the possibility of free movement of the user in any direction and the simultaneous stimulation of several of his/her senses, most often sight, hearing, touch and sense of balance. Moreover, all the techniques discussed previously in Chapters 4-6 may be integrated in the virtual worlds to do both, inducing a specific behavior of the immersed user and providing feedback from the user to the 3D scene generation system. Numerous examples of such applications are presented and discussed in the chapter (from the Preface by Bogdan Wiszniewski, p. iii)

  • Vision Zero in Poland
    • Kazimierz Jamroz
    • Aleksandra Romanowska
    • Lech Michalski
    • Joanna Żukowska
    2022 Pełny tekst

    Poland’s experience of road safety work is relatively short. In the early 1990s road deaths soared to a staggering 8000 a year. A diagnosis found that Poland’s lack of systemic road safety action was to blame for those figures. In response, the state set up road safety bodies and commissioned road safety programs. In 2005, Poland followed the example of Sweden and adopted Vision Zero as a far-reaching concept of changes in road safety. The work that followed helped to improve the situation and reach less than 3000 fatalities in 2015. Despite that, for years Poland has been notorious for its road accident deaths, which are some of the highest in the EU. Poland has had its share of both successes and failures. The results of road safety policies are still below the expectations and many problems have not been solved. Road accidents are not considered a major problem. As a consequence, they are low on political agendas and the institutions remain ineffective due to a sense of collective responsibility for road safety problems. Achieving Vision Zero will require many changes, learning from past mistakes, taking advantage of the experience of the best performing countries, and, above all, taking effective and efficient actions with their systematic monitoring. This chapter is a summary of the last 30 years of road safety work in Poland. It presents a diagnosis of Poland’s problems, an assessment of the policies so far, and the likelihood of achieving the assumptions of Vision Zero in the future. Building on this, recommendations are given on the next steps Poland should take to improve its road safety.

  • Voltage profiles improvement in a power network with PV energy sources – results of a voltage regulator implementation
    • Agata Szultka
    • Seweryn Szultka
    • Stanisław Czapp
    • Robert Karolak
    • Marcin Andrzejewski
    • Jacek Kapitaniak
    • Marcin Kulling
    • Jan Bonk
    2022 Pełny tekst ENERGIES

    The constant increase in the number of photovoltaic (PV) energy sources in distribution networks is the cause of serious voltage problems. The networks built at least a dozen years ago are not provided for the installation of a large number of micro-sources. It happens that the previously properly functioning power networks are not able to provide to consumers power with the required parameters, after installing many PV sources. The problem relates especially to the level of voltage in the networks. This phenomenon sometimes occurs on sunny days, especially in summer. This paper discusses the use of a Low-Voltage Regulator (LVR-sys) in a selected rural distribution network with PV micro-sources. Measured voltage levels in this network, before application and after application of this regulator, are presented. The application of the regulator significantly improved voltage levels in the network and enabled these levels to be maintained within the normative range.

  • Volumetric incorporation of NV diamond emitters in nanostructured F2 glass magneto-optical fiber probes
    • Adam Filipkowski
    • Mariusz Mrózek
    • Grzegorz Stępniewski
    • Jakub Kierdaszuk
    • Aneta Drabińska
    • Tanvi Karpate
    • Maciej Głowacki
    • Mateusz Ficek
    • Wojciech Gawlik
    • Ryszard Buczyński
    • Adam M. Wojciechowski
    • Robert Bogdanowicz
    • Mariusz Klimczak
    2022 Pełny tekst CARBON

    Integration of optically-active diamond particles with glass fibers is a powerful method of scaling diamond's magnetic sensing functionality. We propose a novel approach for the integration of diamond particles containing nitrogen-vacancy centers directly into the fiber core. The core is fabricated by stacking the preform from 790 soft glass canes, drawn from a single rod dip-coated with submicron diamond particles suspended in isopropyl alcohol. This enables manual control over the distribution of nanoscale features, here – the diamond particles across the optical fiber core. We verify this by mapping the diamond distribution in the core using confocal microscopy. The particles are separated longitudinally by 12–29 μm, while in the transverse plane a separation of approximately 1.5–2.2 μm is observed, corresponding to the individual cane diameter in the final fiber, and without significant agglomeration. The fiber's magnetic sensitivity is confirmed in optically detected magnetic resonance recorded with a coiled, 60-cm-long fiber sample with readout contrast of 1.3% limited by microwave antenna coverage. Moreover, magnetic-field dependence of the NV─ fluorescence intensity is demonstrated in the absence of microwaves magnetic, allowing magnetometric applications with a large (from 0 to 35 mT) B-field dynamic range.

  • W klimacie zmian
    • Katarzyna Zielonko-Jung
    2022 Architektura-Murator

    Artykuł ma charakter popularnonaukowy. Dotyczy tendencji projektowania i budowania obiektów architektonicznych zgodnie z tendencjami środowiskowymi. Prezentuje ewolucje podejścia, która zaobserwować można w ciąg ostatnich 30 lat oraz zarysowuje tendencje na przyszłości.

  • Wage determination, Global Value Chains and role played by wage bargaining schemes: The case of Poland
    • Dagmara Nikulin
    • Anna Wolszczak
    2022 Pełny tekst Economics and Business Review

    This study examines the linkages between GVC involvement and wages in Poland given different wage bargaining schemes. The analysis is based on microdata from the European Structure of Earnings Survey for Poland combined with sectoral data from the World Input-Output Database. In particular, two measures of GVC involvement were used: the share of foreign value added (FVA) to export and the measure of traditional offshoring. The institutional settings are represented by the wage bargaining scheme which reflects the level at which the collective pay is agreed. The results show that despite the lack of a significant relationship between the sectoral involvement in GVC and the level of wages in Poland, on average workers covered by the collective pay agreement receive higher wages. Moreover, the wage-GVC nexus is conditioned on the type of pay agreements: the positive wage effect from national agreements is eliminated for a certain range of GVC intensity.

  • Walizka – nocny Bagaż…SEN, Galeria Szklarnia, Szkoła Filmowa w Łodzi
    • Dominika Krechowicz
    2022

    Walizka – nocny Bagaż…SEN, Galeria Szklarnia, Szkoła Filmowa w Łodzi, 20.04 - 31.05.2022. Wystawa w ramach projektu "Walizka". http://www.szklarniaszkolyfilmowej.pl/wystawa/31 Koncepcja wystawy - prof. dr hab.Zbigniew Szot.

  • Wall of Love
    • Krzysztof Wróblewski
    2022

    Swoistym nawiązaniem do monumentalnych realizacji Krzysztofa Wróblewskiego w przestrzeni publicznej jest obraz Wall of love. To pokryta mozaiką z trójkątów i rombów ściana z napisami love. Ale ściana miłości może być zarówno nawiązaniem do popkulturowego banału, w jaki zamieniło się słowo love albo alternatywą dla dzielących ludzi murów.

  • warsztaty "DOMEK LICHA: KASZUBSKIE SCHRONIENIE"
    • Agnieszka Kurkowska
    2022

    Po krótkiej prelekcji o uwarunkowaniach kaszubskich przedstawiony został koncept postaci – kaszubskiego Licha do indywidualnej wizualizacji/ kreacji. Następnie każdy uczestnik/ uczestniczka stworzył plastyczny obraz Licha na przygotowanej karcie pracy i naszkicuje dla niego koncepcję domku – w lesie/ na polu/ nad jeziorem na Kaszubach. Wówczas uczestnicy zostali zapoznani z przygotowanymi dla nich materiałami – naturalnymi i ‘przemysłowo-produktowymi’ również ‘recyklingowymi’ poprzez wskazanie ich cech i walorów obiektywnych. Ostatnim – kluczowym – etapem warsztatów było stworzenie modelu domku dla Licha wpasowanego w realia kaszubskie i dopasowanego do tej postaci. Jedynym ograniczeniem pozostała dziecięca wyobraźnia.

  • Waste management in the mining industry of metals ores, coal, oil and natural gas - A review
    • Szymon Kalisz
    • Katarzyna Kibort
    • Joanna Mioduska
    • Marek Lieder
    • Aleksandra Małachowska
    2022 Pełny tekst JOURNAL OF ENVIRONMENTAL MANAGEMENT

    Waste generated due to mining activity poses a serious issue due to the large amounts generated, even up to 65 billion tons per year, and is often associated with the risk posed by its storage and environmental management. This work aims to review waste management in the mining industry of metals ores, coal, oil and natural gas. It includes an analysis and discussion on the possibilities for reuse of certain types of wastes generated from mining activity, and discusses the benefits, disadvantages and the impact of waste management on the environment. The article presents current methods of waste management arising during the extraction and processing of raw materials and the threats resulting from its application. Furthermore, the potential methods of mining waste management are discussed through an in-depth characterization of the properties and composition of various types of rocks. The presented work addresses not only the issues of more sustainable management of waste from the mining industry, but also responds to the current efforts to implement the assumptions of a circular economy, which is aimed at closing the loop. The methods of recycling by-products and treating waste as a resource more and more often not only meet environmental expectations, but also become a legal requirement. In this respect, the presented work can serve as a valuable support in decision-making about waste management.

  • Waste tire rubber devulcanization technologies: State-of-the-art, limitations and future perspectives
    • Paulina Wiśniewska
    • Shifeng Wang
    • Krzysztof Formela
    2022 Pełny tekst WASTE MANAGEMENT

    Waste tires management is a serious and global environmental problem. Therefore, searching for low-cost and industrial-scale applicable tire recycling methods is gaining more and more attention. Waste tire rubber is valuable source of secondary raw materials for the circular economy and current trends indicate that application of waste rubbers during manufacturing value-added products should increase in near future. Sustainable development of rubber devulcanization technologies and appropriate design of cradle-to-cradle loops for rubber goods are the most promising strategies for achieving a higher level of rubber recycling. This work presents the state-of-the-art in the patented waste tire rubber devulcanization technologies including dynamic desulfurization, reactive extrusion, microwave treatment, and also other less popular methods. Special attention was focused on the used components, rubber treatment conditions and static mechanical properties of reclaimed rubbers. Moreover, environmental aspects and limitations related to rubber devulcanization technologies implementation are also discussed. Our findings showed that reclaimed rubbers described in patents are characterized by higher tensile strength and elongation break (depending on devulcanization technology median: 16.6–19.0 MPa and 321–443%, respectively) compared to the literature data (median: 10.3 MPa and 309%) or commercial products (median: 6.8 MPa and 250%). The significant differences observed in performance properties of reclaimed rubbers resulted mainly from devulcanization efficiency related to waste tires composition or source and rubber treatment conditions. Considering environmental and economic aspects, reactive extrusion is the most promising method further development rubber devulcanization technologies.

  • Wavelet filtering of signals without using model functions
    • Yurii Taranenko
    • Nina Rizun
    2022 Pełny tekst Radioelectronics and Communications Systems

    The effective wavelet filtering of real signals is impossible without determining their shape. The shape of a real signal is related to its wavelet spectrum. For shape analysis, a continuous color wavelet spectrogram of signal level is often used. The disadvantage of continuous wavelet spectrogram is the complexity of analyzing a blurry color image. A real signal with additive noise strongly distorts the spectrogram based on continuous wavelet analysis compared to a pure signal. Therefore, the identification of a real signal by using a continuous color wavelet spectrogram is difficult. To solve this problem, for the first time, a comparative analysis of spectrograms of signals and correlation matrices is carried out. The spectrograms of signals are obtained based on continuous wavelet transformation in the form of images with areas of different colors of variable intensity. To filter the identified signal, a recursive algorithm was used, consisting of successive iterations of the filtering parameters in order to reduce the error. The study of the algorithm on groups of twenty special signals showed a decrease in the number of iterations in comparison with known methods. Correlation matrices are computed by using mathematical functions of the coefficients of discrete wavelet spectra

  • Wdrożenie systemu MEC w sieciach WLAN: Moduł współpracy serwera MEC z siecią dostępową WLAN
    • Michał Hoeft
    • Krzysztof Gierłowski
    • Józef Woźniak
    • Wojciech Gumiński
    • Krzysztof Nowicki
    • Jacek Rak
    2022 Pełny tekst Przegląd Telekomunikacyjny + Wiadomości Telekomunikacyjne

    W artykule zaprezentowano zasady funkcjonowania modułu współpracy sieci dostępowych WLAN z serwerem MEC oraz pozostałymi komponentami ekosystemu, budowanego w ramach projektu SyMEC. Zaproponowana architektura pozwala na ujednolicenie dostępnej funkcjonalności oraz komunikację zewnętrznych aplikacji z podmodułami odpowiedzialnymi za zbieranie i przekazywanie informacji o sieci dostępowej. Jako przykładową aplikację zademonstrowano wizualizację szeregu parametrów sieci dostępowej WLAN.

  • Weather Routing System Architecture Using Onboard Data Collection and Route Optimisation
    • Joanna Szłapczyńska
    • Roberto Vettor
    • Rafal Szlapczynski
    • Mirosław Łącki
    • Marcin Życzkowski
    • Miguel A. Hinostroza
    • Fernando P. Santos
    • Wojciech Tycholiz
    • Carlos Guedes Soares
    2022 Pełny tekst Polish Maritime Research

    This paper describes the architecture of a weather routing system consisting of two key elements: onboard monitoring and route optimiser sub-systems. The former is responsible for collecting various onboard measurements, such as current ship position or ship motion variables. These data, when gathered and processed, are then used for fine-tuning a ship model. The model, together with weather forecasts, is utilised by a multi-objective route optimiser to estimate forecasted ship responses during the voyage. The route optimiser has been developed in a client-server architecture to reallocate all necessary high-tech resources to the server side and keep the client software as simple and light as possible. The system also includes a module responsible for optimising transmission costs, to reduce onboard transmission during the voyage. The entire solution has been deployed onboard the demonstrator ship ‘Monte da Guia’ and tested during its operations at sea.

  • Weighted 2-sections and hypergraph reconstruction
    • Robert Janczewski
    • Paweł Obszarski
    • Krzysztof Turowski
    2022 THEORETICAL COMPUTER SCIENCE

    In the paper we introduce the notion of weighted 2-sections of hypergraphs with integer weights and study the following hypergraph reconstruction problems: (1) Given a weighted graph , is there a hypergraph H such that is its weighted 2-section? (2) Given a weighted 2-section , find a hypergraph H such that is its weighted 2-section. We show that (1) is NP-hard even if G is a complete graph or integer weights w does not exceed 2. Next, we show that (2) is solvable in linear time if G is a partial 2-tree, 2-degenerated or its degree does not exceed 4.