2021 - Repozytorium publikacji - Politechnika Gdańska

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Load capacity of steel-aluminium brackets under static and cyclic laboratory tests
- Andrzej Ambroziak
2021 Pełny tekst Archives of Civil Engineering
The aim of the research is the laboratory investigation of steel-aluminium brackets employed to fasten lightweight curtain walls to building facilities. Static pressure, suction forces, and cyclic loads parallel to end plates (horizontal – to simulate wind influence) were applied in the study. The steel-aluminium brackets were tested on a reinforced concrete substrate made of C30/37 concrete class to simulate the real working conditions. Laboratory tests were performed to failure of the brackets or damage of anchoring fastened to the concrete elements. Additionally, the tensile capacity of stainless steel bolt connections screwed in aluminium profile was determined. The uniaxial tensile tests were performed for three length variants of the anchorage: 28 mm, 14 mm, and 7 mm of the stainless steel bars screw-in in threading aluminium profiles. In the course of cyclic tests, a hinge formed in the location of bolt connections made the change of the working character of steel-aluminium brackets. The cyclic tests also showed the danger of the strap aluminium profile displacement due to improper connection with the main aluminium profile. The paper is intended to provide scientists, civil engineers, and designers with an experimental assessment of mechanical properties of steel-aluminium brackets under static and cyclic loads.
Local material symmetry group for first- and second-order strain gradient fluids
- Victor Eremeev
2021 Pełny tekst MATHEMATICS AND MECHANICS OF SOLIDS
Using an unified approach based on the local material symmetry group introduced for general first- and second-order strain gradient elastic media, we analyze the constitutive equations of strain gradient fluids. For the strain gradient medium there exists a strain energy density dependent on first- and higher-order gradients of placement vector, whereas for fluids a strain energy depends on a current mass density and its gradients. Both models found applications to modeling of materials with complex inner structure such as beam-lattice metamaterials and fluids at small scales. The local material symmetry group is formed through such transformations of a reference placement which cannot be experimentally detected within the considered material model. We show that considering maximal symmetry group, i.e. material with strain energy that is independent of the choice of a reference placement, one comes to the constitutive equations of gradient fluids introduced independently on general strain gradient continua.
Locust bean gum as green and water-soluble binder for LiFePO4 and Li4Ti5O12 electrodes
- Paweł Jakóbczyk
- Michał Bartmański
- Ewelina Rudnicka
2021 Pełny tekst JOURNAL OF APPLIED ELECTROCHEMISTRY
Locust Bean Gum (LBG, carob bean gum) was investigated as an environmentally friendly, natural, and water-soluble binder for cathode (LFP) and anode (LTO) in lithium-ion batteries (Li-ion). For the frst time, we show LBG as an electrode binder and compare to those of the most popular aqueous (CMC) and conventional (PVDF) binders. The electrodes were characterized using TGA/DSC, the galvanostatic charge–discharge cycle test, cyclic voltammetry (CV), and electrochemical impedance spectroscopy (EIS). Thermal decomposition of LBG is seen to begin above 250 °C with a weight loss of about 60 wt% observed at 300 °C, which is sufcient to ensure stable performance of the electrode in a Li-ion battery. For CMC, weight loss at the same temperature is about 45%. Scanning electron microscopy (SEM) shows that the LFP–LBG system has a similar distribution of conductive carbon black particles to PVDF electrodes. The LTO–LBG electrode has a homogeneous dispersion of the electrode elements and maintains the electrical integrity of the network even after cycling, which leads to fast electron migration between LTO and carbon black particles, as well as ion conductivity between LTO active material and electrolyte, better than in systems with CMC and PVDF. The exchange current density, obtained from impedance spectroscopy fell within a broad range between 10−4 and 10−2 mA cm−2 for the LTO|Li and LFP|Li systems, respectively. The results presented in this paper indicate that LBG is a new promising material to serve as a binder.
Long-Term Impact of Wind Erosion on the Particle Size Distribution of Soils in the Eastern Part of the European Union
- Lenka Lackóová
- Jozefína Pokrývková
- Jana Kozlovsky Dufková
- Agnieszka Policht-Latawiec
- Krystyna Michałowska
- Jolanta Dąbrowska
2021 Pełny tekst ENTROPY
Wind erosion is the leading cause of soil degradation and air pollution in many regionsof the world. As wind erosion is controlled by climatic factors, research on this phenomenon isurgently needed in soil and land management in order to better adapt to climate change. In thispaper, the impact of wind erosion on the soil surface in relation to particle size distribution wasinvestigated. Changes in percentage of sand, silt and clay fractions based on historical KPP data(1961–1970), LUCAS data base (2009), and field measurements (2016) were analysed in five cadastralareas impacted by wind erosion (Záhorie Lowlands, Slovakia). With the use of GIS tools, models ofspatial distribution of sand, silt, clay and erodible fraction (EF) content were developed based onthose measurements. Our findings proved that soil texture change driven by wind erosion couldhappen relatively quickly, and a significant proportion of soil fine particles may be carried awaywithin a few years. The results indicate that the soil surface became much rougher over the period ofmore than 50 years, but also that the accumulation of fraction of the silt particles occurred in most ofthe areas affected by the erosive effect.Keywords:aeolian erosion; land degradation; GIS; sustainable agroecosystems; decision-makingprocesses; soil protection; wind erosion indicators; landscape entropy and stability1. IntroductionSoil erosion is a major cause of global-scale land degradation, and has increased by2.5% between 2001 and 2012. The main reasons for this increase are considered to be defor-estation and cropland expansion [1,2]. Soil erosion by wind is the process of destruction,separation, transportation and deposition of soil particles that affects negatively land andhuman health, agricultural production, as well as ecosystem services [3–5]. The process iscontrolled by several factors such as: wind speed and direction, temperature, precipitation,soil wetness, surface roughness, soil texture and aggregation, soil organic matter, vegetationcover, field size, agricultural activities and protective measures [6,7].
Looking Up to the Stars. A Call for Action to Save New Zealand’s Dark Skies for Future Generations to Come
- Karolina Zielińska-Dąbkowska
- Kyra Xavia
2021 Pełny tekst Sustainability
The rapid development of technology coupled with humanity’s desire to reach beyond terra firma, has resulted in more than 60 years of Outer Space activities. Although the exploration of space has provided many advantages and benefits to society so far, including vast, new information that has greatly added to our understanding of our planet and beyond, unfortunately, mankind’s footprint has negative aspects that need to be minimised as much as possible. In recent decades, a major worldwide problem has emerged in regard to the significant increase in light pollution from ground-based illuminations, as well as a lack of proper regulatory frameworks to mitigate the issue in order to protect the night sky and astronomical research. More recently, due to the escalating demand of air space for microsatellites and the rapid development of these new space technologies, as well as unmanned aerial vehicles (UAV), a new problem has arisen connected to visual light pollution (VLP). New Zealand has been especially affected, as, because of its dark skies, it has the third highest number of astronomical observatories in the world. The aim of this research is to identify critical areas for broader investigation; an action plan to improve the impact of new technologies is urgently required, not only at a national level but also worldwide. This is crucial in order to preserve humanity’s right to access the night sky and to also enable continual professional and amateur night-time observations for the present and the future, as well as for New Zealand to become a Dark Sky Nation.
Low-coherence photonic method of electrochemical processes monitoring
- Monika Kosowska
- Paweł Jakóbczyk
- Michał Rycewicz
- Alex Vitkin
- Małgorzata Szczerska
2021 Pełny tekst Scientific Reports
We present an advanced multimodality characterization platform for simultaneous optical and electrochemical measurements of ferrocyanides. Specifcally, we combined a fber-optic Fabry– Perot interferometer with a three-electrode electrochemical setup to demonstrate a proof-ofprinciple of this hybrid characterization approach, and obtained feasibility data in its monitoring of electrochemical reactions in a boron-doped diamond flm deposited on a silica substrate. The flm plays the dual role of being the working electrode in the electrochemical reaction, as well as afording the refectivity to enable the optical interferometry measurements. Optical responses during the redox reactions of the electrochemical process are presented. This work proves that simultaneous opto-electrochemical measurements of liquids are possible.
Low-Cost Modeling of Microwave Components by Means of Two-Stage Inverse/Forward Surrogates and Domain Confinement
- Sławomir Kozieł
- Anna Pietrenko-Dąbrowska
- Ullah Ubaid
2021 Pełny tekst IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES
Full-wave electromagnetic (EM) analysis is one of the most important tools in the design of modern microwave components and systems. EM simulation permits reliable evaluation of circuits at the presence of cross-coupling effects or substrate anisotropy, as well as for accounting for interactions with the immediate environment. However, repetitive analyses required by EM-driven procedures, such as parametric optimization or statistical analysis, may entail considerable computational expenditures, often prohibitive. Tackling the high-cost issue fostered the shift toward the incorporation of fast replacement models, including both physics-based surrogates and data-driven ones. While the latter is more popular and versatile, the construction of reliable approximation metamodels for microwave components is hindered by the curse of dimensionality and nonlinearity of system responses. The recent performance-driven modeling methodologies are capable of alleviating these difficulties by confining the surrogate domain to a vicinity of the optimum design manifold (i.e., the region that contains high-quality designs rather than the entire parameter space). Although setting up the model in a constrained domain requires small amounts of training data, domain definition itself requires a set of preoptimized reference designs, acquisition of which is an expensive endeavor. This work proposes a novel approach, which replaces the reference designs with a small set of random observables, thereby considerably reducing the overall cost of the model setup. Comprehensive verification involving several miniaturized microstrip structures demonstrates that our methodology is competitive to performance-driven frameworks both in terms of modeling accuracy and computational efficiency with an average savings of around 80%.
Low-cost multi-criterial design optimization of compact microwave passives using constrained surrogates and dimensionality reduction
- Sławomir Kozieł
- Anna Pietrenko-Dąbrowska
- Muath Al-hasan
2021 Pełny tekst INTERNATIONAL JOURNAL OF NUMERICAL MODELLING-ELECTRONIC NETWORKS DEVICES AND FIELDS
Design of contemporary microwave circuits is a challenging task. Typically, it has to take into account several performance requirements and constraints. The design objectives are often conflicting and their simultaneous improvement may not be possible; instead, compromise solutions are to be sought. Representative examples are miniaturized microwave passives where reduction of the circuit size has a detrimental effect on its electrical characteristics. Acquiring information about the best possible design trade‐offs is invaluable for the designer, yet it entails computationally expensive multi‐objective optimization (MO). MO is typically conducted using population‐based metaheuristic algorithms, the cost of which might be extremely high. If the circuit performance is evaluated using full‐wave electromagnetic (EM) analysis, this cost is often prohibitive. A workaround is the employment of fast surrogate models, and a number of surrogate‐assisted frameworks have been proposed in the literature. Unfortunately, a construction of reliable surrogates is hindered in higher dimensional parameter spaces. The recently proposed constrained modeling mitigates this issue to a certain extent by restricting the modeling process to the region containing the Pareto front to be found. This work proposes a novel surrogate‐based MO technique that involves constrained modeling and explicit reduction of the surrogate domain dimensionality. The latter is achieved through the spectral analysis of the extreme Pareto‐optimal design set obtained by local search routines. Our methodology is validated using a 15‐parameter impedance‐matching transformer with the Pareto set identified at the cost of a few hundred EM analyses of the circuit. The numerical experiments also demonstrate a significant reduction of the optimization cost as compared to the state‐of‐the‐art surrogate‐assisted MO methods.
Low-Cost Unattended Design of Miniaturized 4 × 4 Butler Matrices with Nonstandard Phase Differences
- Adrian Bekasiewicz
- Sławomir Kozieł
2021 Pełny tekst SENSORS
Design of Butler matrices dedicated to Internet of Things and 5th generation (5G) mobile systems—where small size and high performance are of primary concern—is a challenging task that often exceeds capabilities of conventional techniques. Lack of appropriate, unified design approaches is a serious bottleneck for the development of Butler structures for contemporary applications. In this work, a low-cost bottom-up procedure for rigorous and unattended design of miniaturized 4 × 4 Butler matrices is proposed. The presented approach exploits numerical algorithms (governed by a set of suitable objective functions) to control synthesis, implementation, optimization, and fine-tuning of the structure and its individual building blocks. The framework is demonstrated using two miniaturized matrices with nonstandard output-port phase differences. Numerical results indicate that the computational cost of the design process using the presented framework is over 80% lower compared to the conventional approach. The footprints of optimized matrices are only 696 and 767 mm2, respectively. Small size and operation frequency of around 2.6 GHz make the circuits of potential use for mobile devices dedicated to work within a sub-6 GHz 5G spectrum. Both structures have been benchmarked against the state-of-the-art designs from the literature in terms of performance and size. Measurements of the fabricated Butler matrix prototype are also provided.
Low-power microwave-induced fabrication of functionalised few-layer black phosphorus electrodes: A novel route towards Haemophilus Influenzae pathogen biosensing devices
- Paweł Jakóbczyk
- Marcin Kowalski
- Mateusz Brodowski
- Anna Dettlaff
- Bartłomiej Dec
- Dawid Nidzworski
- Jacek Ryl
- Tadeusz Ossowski
- Robert Bogdanowicz
2021 Pełny tekst APPLIED SURFACE SCIENCE
In this paper, various passivation schemes were applied at few-layer black phosphorus (FLBP) to achieve covalent functionalisation with 4-azidobenzoic acid, improving its electrochemical response intended for analytical and biosensing applications. The thermal and microwave assisted modification procedures in toluene and dime-thylformamide resulted in high reversibility of reactions on functionalised FLBP using a ferricyanide/ferrocya-nide redox probe. The lowest peak-to-peak separation of 91 mV, and high kinetics were obtained by thermal synthesis in dimethylformamide. Attachment of a =N-phenylene-COOH moiety to the FLBP limits its degradation under ambient conditions delivering a linker for a peptide bond with proteins in the –NH2 groups. The functionalised FLBP was applied for impedimetric detection of the Haemophilus Influenzae (HI) bacterial protein with a low limit of detection (LOD) of 5.82 μg mL-1 along with high sensitivity equal to 1.267% μg-1 mL. The proposed strategy delivers a novel phosphorene-based electrode for sensitive detection of various bacterial pathogens.
Low-strain sensor based on the flexible boron-doped diamond-polymer structures
- Michał Rycewicz
- Mateusz Ficek
- Krzysztof Gajewski
- Srinivasu Kunuku
- Jakub Karczewski
- Teodor Gotszalk
- I. Wlasny
- Andrzej Wysmołek
- Robert Bogdanowicz
2021 Pełny tekst CARBON
A free-standing high boron-doped diamond nanosheet (BDDNS) has been fabricated for the development of a flexible BDDNS strain senor. High boron-doped diamond was initially grown on a tantalum substrate in a microwave plasma-assisted chemical vapor deposition method, and was then transferred to a Kapton polymer substrate to fabricate the flexible BDDNS/Kapton device. Before performing the transfer process, the thin BDDNS’s morphology and bonding structure on the top and bottom surfaces were investigated using scanning electron microscopy and Raman spectroscopy. The contact potential difference and work function values of the BDDNS top and bottom surfaces were measured using a Kelvin probe atomic force microscope. Significant electrical conducting properties were observed from the resistance mapping of the BDDNS foil, and the average resistance value of 31 Ω attained from the top surface of the BDDNS foil. The electrical response of the BDDNS/Kapton device was investigated using a custom-made measurement system and a positive residual resistance change with strain was observed. The developed BDDNS/Kapton device was able to sustain for measuring up to 0.55% of strain, which indicates it may have great potential to be utilized in low-strain sensor applications.
Machine Learning and Electronic Noses for Medical Diagnostics
- Wojciech Wojnowski
- Kaja Kalinowska
2021
The need for noninvasive, easy-to-use, and inexpensive methods for point-of-care diagnostics of a variety of ailments motivates researchers to develop methods for analyzing complex biological samples, in particular human breath, that could aid in screening and early diagnosis. There are hopes that electronic noses, that is, devices based on arrays of semiselective or nonselective chemical sensors, can fill this niche. Electronic olfaction uses data processing and machine learning to build classification models based on the responses of several sensors in the form of multivariate datasets in order to discriminate between disease and healthy control based on a unique fingerprint. However, the introduction of this technique in clinical settings is limited by methodological issues which can, to some extent, be remedied using artificial intelligence. In this chapter, we provide a brief introduction to the electronic nose technique and outline its applications in medical diagnostics. We also discuss the ways in which data processing and machine learning techniques can be used to facilitate the use of electronic olfaction in the detection of disease.
MACHINE LEARNING APPLICATIONS IN RECOGNIZING HUMAN EMOTIONS BASED ON THE EEG
- Adrian Kastrau
- Michał Koronowski
- Mariusz Liksza
- Patryk Jasik
2021
This study examined the machine learning-based approach allowing the recognition of human emotional states with the use of EEG signals. After a short introduction to the fundamentals of electroencephalography and neural oscillations, the two-dimensional valence-arousal Russell’s model of emotion was described. Next, we present the assumptions of the performed EEG experiment. Detail aspects of the data sanitization including preprocessing, feature extraction, and target variable creation were also given. At the modeling stage, we created several classification models to establish a benchmark ranking of the problem related to the recognition of human emotions. Such a methodological approach enabled us to confirm that it is possible to build machine learning solutions allowing to recognize and classify human emotions with very high accuracy of over 90%.
Machine-Learning-Powered EM-Based Framework for Efficient and Reliable Design of Low Scattering Metasurfaces
- Sławomir Kozieł
- Muhammad Abdullah
2021 Pełny tekst IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES
Popularity of metasurfaces has been continuously growing due to their attractive properties including the ability to effectively manipulate electromagnetic (EM) waves. Metasurfaces comprise optimized geometries of unit cells arranged as a periodic lattice to obtain a desired EM response. One of their emerging application areas is the stealth technology, in particular, realization of radar cross section (RCS) reduction. Despite potential benefits, a practical obstacle hindering widespread metasurface utilization is the lack of systematic design procedures. Conventional approaches are largely intuition-inspired and demand heavy designer's interaction while exploring the parameter space and pursuing optimum unit cell geometries. Not surprisingly, these are unable to identify truly optimum solutions. In this article, we introduce a novel machine-learning-based framework for automated and computationally efficient design of metasurfaces realizing broadband RCS reduction. Our methodology is a three-stage procedure that involves global surrogate-assisted optimization of the unit cells, followed by their local refinement. The last stage is direct EM-driven maximization of the RCS reduction bandwidth, facilitated by appropriate formulation of the objective function involving regularization terms. The appealing feature of the proposed framework is that it optimizes the RCS reduction bandwidth directly at the level of the entire metasurface as opposed to merely optimizing unit cell geometries. Computational feasibility of the optimization process, especially its last stage, is ensured by high-quality initial designs rendered during the first two stages. To corroborate the utility of our procedure, it has been applied to several metasurface designs reported in the literature, leading to the RCS reduction bandwidth improvement by 15%-25% when compared with the original designs. Furthermore, it was used to design a novel metasurface featuring over 100% of relative bandwidth. Although the procedure has been used in the context of RCS design, it can be generalized to handle metasurface development for other application areas.
Magnetosonic Excitation of the Entropy Perturbations in a Plasma with Thermal Conduction Depending on Temperature
- Anna Perelomova
2021 Pełny tekst Archives of Acoustics
Nonlinear excitation of the entropy perturbations by magnetosonic waves in a uniform and infinite plasma model is considered. The wave vector of slow or fast mode forms an arbitrary angle (0 B B ) with the equilibrium straight magnetic field, and all perturbations are functions of the time and longitudinal coordinate. Thermal conduction is the only factor which destroys isentropicity of wave perturbations and causes the nonlinear excitation of the entropy mode. A dynamic equation is derived which describes excitation of perturbation in the entropy mode in the field of dominant magnetosonic mode. Effects associatiated with temperature dependent and anisotropic thermal conduction are considered and discussed.
Management of Dark Fermentation Broth via Bio Refining and Photo Fermentation
- Karolina Kucharska
- Patrycja Makoś-Chełstowska
- Edyta Słupek
- Jacek Gębicki
2021 Pełny tekst ENERGIES
Lignocellulose and starch-based raw materials are often applied in the investigations regarding biohydrogen generation using dark fermentation. Management of the arising post-fermentation broth becomes a problem. The Authors proposed sequential processes, to improve the efficiency of both hydrogen generation and by-products management carried under model conditions. During the proposed procedure, the simple sugars remaining in broth are converted into organic acids, and when these products are used as substrates for the photo fermentation process. To enhance the broth management also conditions promoting Deep Eutectic Solvents (DES) precursors synthesis are simultaneously applied. Application of Box-Behnken design allows defining of the optimal conditions for conversion to DESs precursors. During the procedure hydrogen was obtained, the concentration of hydrogen in the photo fermentation reached up to 819 mL H2/L medium/7 d, depending on the broth type, i.e., when the broth was optimized for formic acid concentration. The DESs precursors were separated and engaged in DESs synthesis. To confirm the formation of the DESs, FT-IR analyses were performed. The Chemical Oxygen Demand of post-fermentation broths after dark fermentation optimized for formic acid was reduced by ca. 82%. The proposed procedure can be successfully used as a method of post-fermentation broth management.
Management of Urban Waters with Nature-Based Solutions in Circular Cities—Exemplified through Seven Urban Circularity Challenges
- Hasan Volkan Oral
- Matej Radinja
- Anacleto Rizzo
- Katharina Kearney
- Theis Raaschou Andersen
- Pawel Krzeminski
- Gianluigi Buttiglieri
- Derya Ayral-Cinar
- Joaquim Comas
- Magdalena Gajewska
- Marco Hartl
- David Christian Finger
- Jan K. Kazak
- Harri Mattila
- Patrícia Vieira
- Patrizia Piro
- Stefania Anna Palermo
- Michele Turco
- Behrouz Pirouz
- Alexandros Stefanakis
- Martin Regelsberger
- Nadia Ursino
- Pedro Carvalho
2021 Pełny tekst Water
Nature-Based Solutions (NBS) have been proven to effectively mitigate and solve resource depletion and climate-related challenges in urban areas. The COST (Cooperation in Science and Technology) Action CA17133 entitled “Implementing nature-based solutions (NBS) for building a resourceful circular city” has established seven urban circularity challenges (UCC) that can be addressed effectively with NBS. This paper presents the outcomes of five elucidation workshops with more than 20 European experts from different backgrounds. These international workshops were used to examine the effectiveness of NBS to address UCC and foster NBS implementation towards circular urban water management. A major outcome was the identification of the two most relevant challenges for water resources in urban areas: ‘Restoring and maintaining the water cycle’ (UCC1) and ‘Water and waste treatment, recovery, and reuse’ (UCC2). s Moreover, significant synergies with ‘Nutrient recovery and reuse’, ‘Material recovery and reuse’, ‘Food and biomass production’, ‘Energy efficiency and recovery’, and ‘Building system recovery’ were identified. Additionally, the paper presents real-life case studies to demonstrate how different NBS and supporting units can contribute to the UCC. Finally, a case-based semi-quantitative assessment of the presented NBS was performed. Most notably, this paper identifies the most typically employed NBS that enable processes for UCC1 and UCC2. While current consensus is well established by experts in individual NBS, we presently highlight the potential to address UCC by combining different NBS and synergize enabling processes. This study presents a new paradigm and aims to enhance awareness on the ability of NBS to solve multiple urban circularity issues.
Managerial Energy in Sustainable Enterprises: Organizational Wisdom Approach
- Monika Stelmaszczyk
- Agata Pierścieniak
- Anna Krzysztofek
2021 Pełny tekst ENERGIES
The circular economy (CE) as an idea involves applying the concept of sustainable development that has been gaining worldwide support. This shift in perception of energy and resource-use from its linear to circular forms creates a specific business environment, which constitutes the subject of this research. This article aims to analyze the impact of a manager’s energy on organizational wisdom, focusing on its circular business model activity. In the beginning, the article focuses on presenting ideas of the circular economy, emphasizing the manager’s activity in implementing strategic and operational tasks. These activities are identified as energy to launch mechanisms for developing organizational wisdom for sustainable enterprise. Assuming that organizational wisdom consists of two dimensions, organizational learning, and absorptive capacity, the research identifies relationships between them. The study was conducted at VIVE Textile Recycling Ltd., (Kielce, Poland). Empirical data were collected from 138 managers using the PAPI technique. Regression analysis and structural equation modeling (SEM) were applied to test the research hypotheses. Main results: Managerial energy (ME) is understood as the active attitude of managers who use knowledge from their environments to achieve goals both in the operational and strategic areas. Being an activating force for sustainable enterprise, ME is viewed as the antecedent to the development of enterprises operating in the CE model. ME directly activates the process of developing organizational wisdom in the area of absorptive capacity (AC) at the stages of assimilation, transformation, and exploitation. The transfer of knowledge from the individual to the organizational level (acquisition) requires a mediator, which is in this case the process of organizational learning (OL).
Managing change through team building in the context of organizing Erasmus+ mobility projects at the Gdańsk Tech Library
- Urszula Szybowska
- Magdalena Stankevic
2021 Pełny tekst Zarządzanie Biblioteką
The article discusses managing change through team building in the context of organizing Erasmus+ mobility projects in the Gdańsk University of Technology Library as the main strategy which contributed to the projects’ success. The authors describe the projects realized in the years 2017-2019 within the scope of the Erasmus+ programme. The organizers decided to take a responsible and active approach towards managing change and effective team building. Adopting and implementing the strategies according to the process of VMOSA (Vision, Mission, Objectives, Strategies, and Action Plans) turned out to be beneficial and made it possible to implement several successful mobility projects. The authors only mention that there might appear destructive factors which can seriously reduce a team’s effectiveness, highlighting the issue of a person or persons with a narcissistic personality disorder, which seems to be overlooked and underestimated in contemporary cross-disciplinary studies and management practice both in academic libraries and in other types of organizations.
MANDARIN PEEL AS AN AUSPICIOUS FUNCTIONAL FILLER FOR POLYMER COMPOSITES
- Aleksander Hejna
- Mateusz Barczewski
- Paulina Kosmela
- Joanna Aniśko
- Olga Mysiukiewicz
- Mariusz Marć
2021 Pełny tekst Macedonian Journal of Chemistry and Chemical Engineering
This work describes the application of mandarin peel (MP) as a waste filler for high-density polyethylene (HDPE) composites. The main goal was to investigate the impact of the filler's essential oils, which include multiple terpenes and terpenoids, on the processing, physicochemical, mechanical, and thermal properties of the composites as a function of different filler content (1 – 10 wt%), as well as its effect on the color and volatile organic compounds emissions of the composites. At small loadings, MP can be considered an efficient filler for wood-polymer composites, enhancing their flowability, tensile strength, and thermal stability. In addition, it may act as a colorant and aroma compound for polymer materials, and can enhance the thermooxidative resistance of composites. The oxidation induction time was increased from 20 min for HDPE up to 62 min for the composites with 10 wt% filler. The research results demonstrate the application of MP not only in the production of highly-filled composites, but also as an additive that significantly enhances the performance of composites at low concentrations.