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  • Ideas of the New European Bauhaus (NEB) in architectural education
    • Antoni Taraszkiewicz
    • Karolina Taraszkiewicz
    2024 Pełny tekst World Transactions on Engineering and Technology Education

    The New European Bauhaus (NEB) is an interdisciplinary project initiated by the European Commission in 2020 [1], based on three values: sustainability, beauty and community (social inclusion). Its aim is to support the European Green Deal programme [2] by accelerating the transformation of various economic sectors, including construction, to improve the quality of people’s lives and protect the natural environment. Even though the NEB ideas have been known in Europe and around the world for over three years, it turns out that they receive very little attention in contemporary architectural education in some countries. A survey conducted among students in the 4th semester of the first-cycle studies in the Faculty of Architecture at Gdańsk University of Technology, Gdańsk, Poland, indicated that students do not know the NEB ideas and do not try to implement them in their design work. Hence, the need to create an appropriate base - a school in which students are able to directly and tangibly encounter all sustainable spatial, functional, technical and technological solutions according to the values and requirements of modern society.

  • Identification of Determinants of Using Crowdfunding as a Source of Financing the Development of Social Enterprises–the Perspective of Polish Social Entrepreneurs
    • Martyna Wronka-Pośpiech
    • Aldona Frączkiewicz-Wronka
    • Maria Węgrzyn
    • Krzysztof Leja
    2024

    Social enterprises face funding challenges caused, among other things, by investors focusing too much on risk and return. As traditional capital markets do not meet the needs of social entrepreneurs, crowdfunding can be an alternative way to raise funds for the development of their business. In this context, crowd-funding has not been sufficiently researched, and its growing importance in business finance makes it worth understanding its impact on social enterprises. Therefore, this paper helps to fill this gap in the literature by analysing social entrepreneurs’ use of alternative forms of finance such as crowdfunding. The observation of social enterprise activities in Poland, which has been carried out systematically for several years, justifies the thesis that this phenomenon as a practical activity is relatively new and research is fragmentary and rather than in-depth. Hence the idea to address this very issue in this paper. Therefore, our study collects qualitative data from 21 social entrepreneurs to find out the reasons that facilitate or hinder its use by social enterprises.

  • Identification of Public Service Logic (PSL) and Public Service Motivation (PSM) elements in Open Government Data (OGD) initiatives
    • Fredrick Ishengoma
    • Shao Deo
    • Raphael Gouvêa
    • Guilherme Costa Wiedenhöft
    • Ricardo Matheus
    • Charalampos Harris Alexopoulos
    • Nina Rizun
    • Stuti Saxena
    2024 Pełny tekst Electronic Journal of Information Systems in Developing Countries

    While previous research on Open Government Data (OGD) has primarily focused on reuse and adoption, this study aims to explore the implications of the Public Service Logic (PSL) and Public Service Motivation (PSM) dimensions in the context of OGD initiatives. This study is contextualized in Tanzania wherein the OGD initiatives are at an evolving stage. For the present study, the perspectives of the 15 public officials involved in the management of the OGD initiatives are being solicited. Findings underscore the need for furthering the marketing and refurbishing the OGD initiatives' quality alongside the increased involvement of the stakeholders to engage in value co-creation. Furthermore, as a study contextualized in a developing country to understand the involvement of the public personnel in the refurbishment of the OGD initiatives, the study contributes to the extant OGD literature while identifying the OGD publisher-side challenges and strengths in a still-evolving OGD initiative. Finally, with its societal implications in terms of the impact on societal stakeholders' engagement with OGD given the PSL-PSM of the public officials, the study's relevance is also clinched

  • Identification of Quasi-Periodically Varying Systems Using the Local Basis Function Approach
    • Artur Gańcza
    • Maciej Niedźwiecki
    2024

    In this paper we propose a solution to the problem of tracking quasi-periodically varying systems based on the local basis function (LBF) approach. Within this framework, parameter trajectories are locally approximated using linear combinations of specific functions of time known as basis functions. We derive both bias and variance characteristics of LBF estimators. Additionally, we demonstrate that the computational burden associated with LBF estimation algorithms can be significantly reduced, without sacrificing high estimation accuracy, by employing the computationally fast, approximate version of the LBF scheme.

  • Identyfikacja instrumentu muzycznego z nagrania fonicznego za pomocą sztucznych sieci neuronowych
    • Maciej Blaszke
    2024 Pełny tekst

    Celem rozprawy jest zbadanie algorytmów do identyfikacji instrumentów występujących w sygnale polifonicznym z wykorzystaniem sztucznych sieci neuronowych. W części teoretycznej przywołano podstawy przetwarzania sygnałów fonicznych w kontekście ekstrakcji parametrów sygnałów wykorzystywanych w treningu sieci neuronowych. Dodatkowo dokonano analizy rozwoju metod uczenia maszynowego z uwzględnieniem podziału na sieci neuronowe pierwszej, drugiej i trzeciej generacji. Opisano także powszechnie stosowane metody archiwizowania wyników treningu sztucznych sieci neuronowych oraz wystąpień artefaktów. Na podstawie przeglądu literatury zaproponowano tezy rozprawy. W części eksperymentalnej w pierwszej kolejności opisano dostępne i zgromadzone zbiory nagrań instrumentów muzycznych oraz sposób ich przekształcenia do formy zbioru treningowego, walidacyjnego i ewaluacyjnego. Przeprowadzono eksperymenty sprawdzające zasadność zaproponowanej koncepcji na mniejszym zbiorze danych. Na tym etapie zaimplementowano modele sieci neuronowych odpowiadające stanowi wiedzy w kontekście identyfikacji instrumentów muzycznych w celu porównania wyników z zaproponowanym modelami. Bazując na wstępnych wynikach, zaproponowano i przeprowadzono rozszerzone eksperymenty na zbiorze danych treningowych zawierających 13 instrumentów muzycznych, w tym rzadko występujących w typowym instrumentarium oraz w bazach muzycznych. W badaniach tych zostały wykorzystane modele sieci neuronowych drugiej oraz trzeciej (sieci impulsowe) generacji, w tym własne propozycje modeli. W końcowej części zawarto analizę uzyskanych wyników oraz omówiono wnioski z niej płynące, służące udowodnieniu tez badawczych. Przedstawiono również najważniejsze osiągnięcia rozprawy oraz kierunki rozwoju badań, mających na celu identyfikację instrumentów muzycznych w sygnale polifonicznym.

  • Imadła maszynowe
    • Adam Barylski
    2024 Projektowanie i Konstrukcje Inżynierskie

    omówiono pokrótce historie imadeł. Przedstawiono budowę imadeł śrubowych, samocentrujących, precyzyjnych, dwudzielnych, uchylno-obrotowych, krzyżowych, hydraulicznych i o konstrukcji blokowej. Podano zakres stosowania poszczególnych rozwiązań.

  • Imidazole-Based Lithium Salt LiHDI as a Solid Electrolyte Interphase-Stabilising Additive for Lithium-Conducting Electrolytes
    • Marek Broszkiewicz
    • Bartosz Brzozowski
    • Tomasz Trzeciak
    • Aldona Zalewska
    • Jacek Ryl
    • Leszek Niedzicki
    2024 Pełny tekst MOLECULES

    Lithium salt LiHDI (lithium 4,5-dicyano-2-(n-heptafluoropropyl)imidazolide) is proposed as a solid electrolyte interphase-stabilising additive for lithium-ion batteries, which can be added in a smaller amount than fluoroethylene carbonate (FEC) and vinylene carbonate (VC) additives. Electrolytes containing either lithium 4,5-dicyano-2-(trifluoromethyl)imidazolide (LiTDI) or battery-standard LiPF6 were tested with various amounts of LiHDI additive. Chemical stability in the presence of water and the thermal stability of LiHDI are on par with LiTDI. LiHDI additive does not negatively affect the properties of electrolytes. Conductivity measurements of solutions, galvanostatic cycling of graphite-LiFePO4 cells at room temperature, cells’ cycling at 60 °C, internal cell resistance monitoring during cycling, and XPS analysis of electrodes’ surfaces after cycling have been performed. LiHDI, unlike the FEC-VC mixture, does not negatively affect the properties of the electrolyte. Cycling showed improved capacity retention with LiHDI additive with both graphite and LiFePO4 as capacity-limiting electrodes over samples without additives. At elevated temperatures, samples with LiHDI exhibited better capacity retention during cycling than those with FEC-VC. Internal cell resistance can be correlated with capacity retention. XPS results show changes in the composition of SEI depending on the composition of the electrolyte and the duration of cycling.

  • Imitating Quantum Probabilities: Beyond Bell’s Theorem and Tsirelson Bounds
    • Marek Czachor
    • Kamil Nalikowski
    2024 Pełny tekst Foundations of Science

    Local hidden-variable model of singlet-state correlations discussed in M. Czachor, Acta Phys. Polon. A 139, 70, is shown to be a particular case of an infinite hierarchy of local hidden-variable models based on an infinite hierarchy of calculi. Violation of Bell-type inequalities can be interpreted as a `confusion of languages' problem, a result of mixing different but neighboring levels of the hierarchy. Mixing of non-neighboring levels results in violations beyond the Tsirelson bounds.

  • Immersion in Virtual Reality: CAVE Automatic Virtual Environments vs. Head-Mounted Displays
    • Michał Mielcarek
    • Miłosz Rzeźniczak
    • Jacek Lebiedź
    2024

    The paper describes immersive capabilities of CAVE Automatic Virtual Environment and Head-Mounted Display. An important aspect of this research was to develop a method for quantifying user immersion in both systems. Two virtual reality applications, "Flat of Negative Emotions" and "Arachnophobia Treatment Support" were used to observe and analyze user reactions and engagement levels. Participants were exposed to these applications in both environments, allowing for a comparative analysis of the technologies. The methodology incorporated surveys, observation forms, and direct interaction analysis, combining qualitative and quantitative data for a comprehensive evaluation of both systems. The study involved 124 participants from varied backgrounds. The paper presents the objectives, methodology, and findings, with a focus on comparing the immersion levels in CAVE and HMD settings. The results contribute to the academic discourse in virtual reality and human-computer interaction, offering methodological advancements in measuring immersion and guiding future research in immersive technology.

  • Immune escape of B-cell lymphoblastic leukemic cells through a lineage switch to acute myeloid leukemia
    • Karolina Bełdzińska-Gądek
    • Ewa Zarzycka
    • Krzysztof Pastuszak
    • Katarzyna Borman
    • Krzysztof Lewandowski
    • Jan M. Zaucha
    • Witold Prejzner
    2024 LEUKEMIA & LYMPHOMA

    Acute leukemia (AL) with a lineage switch (LS) is associated with poor prognosis. The predisposing factors of LS are unknown, apart from KMT2A rearrangements that have been reported to be associated with LS. Herein, we present two cases and review all 104 published cases to identify risk factors for LS. Most of the patients (75.5%) experienced a switch from the lymphoid phenotype to the myeloid phenotype. Eighteen patients (17.0%) experienced a transformation from acute myelogenous leukemia (AML) to acute lymphoblastic leukemia (ALL). Forty-nine (46.2%) patients carried a KMT2A rearrangement. Most of the cases involved LS from B-cell ALL (B-ALL) to AML (59.4%), and 49 patients (46.2%) carried KMT2A-rearrangements. Forty patients (37.7%) received lineage-specific immunotherapy. Our findings suggest that the prevalence of KMT2A rearrangements together with the lineage-specific immunotherapy may trigger LS, which supports the thesis of the existence of leukemia stem cells that are capable of lymphoid or myeloid differentiation.

  • Impact Assessment of Electric Vehicles Integration and Optimal Charging Schemes Under Uncertainty: A Case Study of Qatar
    • Sheetal Deshmukh
    • Hanan Tariq
    • Mohammad Amir
    • Atif Iqbal
    • Mousa Marzband
    • Abdullah M. A. B. Al-Wahedi
    2024 Pełny tekst IEEE Access

    The integration of electric vehicles (EVs) is rapidly growing compared to conventional vehicles in Qatar. To assess how these electric vehicles will impact Qatar’s distribution network, it is necessary to accurately model EV loads. However, EV loads exhibit uncertainties due to driving behaviour in charging time, state of charge (SOC), number of trips, and distance travelled. This necessitates the development of a probabilistic model. The Monte-Carlo method is employed to predict EV charging profiles probabilistically. The generated EV load profiles are assigned to different sectors and compared with the base case voltage profile curve. The IEEE-33 bus system is utilized to evaluate EV impacts considering the load pattern of Qatar. EV load profile generation is performed using MATLAB software, and impact assessment is conducted in DIgSILENT software. The results indicate that following EV integration, the system’s voltage profile experiences drops in the early morning and afternoon. A proposed charging scheme (R2), coupled with the integration of solar PV into the system, can mitigate this voltage drop issue. The PV panels have a rating of 1503 kW and are connected to the 14th bus. In Qatar, the hot summer months span from June to September, so the average PV generation data for September is used. The implementation of the proposed reward charging scheme improves system performance in terms of the voltage profile, ensuring grid resilience.

  • Impact of abiotic stressors on nutrient removal and rhizomicrobiome composition in floating treatment wetland with Equisetum hyemale
    • Nicole Nawrot
    • Przemysław Kowal
    • Ewa Wojciechowska
    • Ksenia Pazdro
    • Jolanta Walkusz-miotk
    • Sławomir Ciesielski
    • Filip M. G. Tack
    2024 Pełny tekst SCIENCE OF THE TOTAL ENVIRONMENT

    Floating treatment wetlands (FTW) are receiving growing interest as a phyto-technology. However, there are significant research gaps regarding the actual role of plant species and plant-microbiome interactions. In this study, the nutrient uptake of Equisetum hyemale was examined in FTW microcosms under the influence of abiotic stressors: As (3 mg/L) and Pb (3 mg/L) as well as Cl− (300 and 800 mg/L) in reference to a control during a short screening experiment. High removal efficiency of nutrients in water solutions, up to 88 % for TN and 93 % for PO4-P, was observed. However, PO4-P removal was inhibited in the As reactor, with a maximum efficiency of only 11 %. Lead and As were removed with high efficiency, reaching 98 % and 79 % respectively. At the same time only Pb was effectively bound to root biomass, reaching up to 51 %. Limited As accumulation of 0.5 % in plant roots suggests that microbial processes play a major role in its reduction. The development and structure of microbiome in the microcosms was analysed by means of 16S rRNA gene amplicon sequencing, proving that Pb was the most influential factor in terms of selection pressure on specified bacterial groups. In the As treatment, the emergence of a Serratia subpopulation was observed, while the Cl− treatment preserved a rhizobiome composition most closely resembling the control. This study indicates that E. hyemale is a suitable species for use in FTWs treating Pb polluted water that at the same time is capable to withstand periodic increases in salinity. E. hyemale exhibits low As binding in biomass; however, extended exposure might amplify this effect because of the slow-acting, but beneficial, mechanism of As uptake by roots and shoots. Microbiome analysis complements insights into mechanisms of FTW performance and impact of stress factors on bacterial structure and functions.

  • Impact of accuracy of weigh-in-motion data for pavement analysis and design: influence of temperature variations
    • Dawid Ryś
    • Przemysław Więckowski
    • Monika Wasilewska
    • Cezary Dołęga
    2024 Road Materials and Pavement Design

    This paper investigates the effect of temperature on WIM-collected data using the steering axle load spectrum (SALS) and two datasets. The first dataset, provided by the WIM system operator, contains detailed raw data, while the second, supplied by the road authority, includes less detailed information but covers 46 stations with various sensor types and configurations: single-line bending plates and two-line quartz piezoelectric sensors. A new methodology and parameter, the Spectral Bias Index, were introduced to evaluate WIM data accuracy. This approach effectively identifies stations operating correctly or incorrectly, with bias percentages of 6% for correct stations and 15% for incorrect ones. These biases significantly influence equivalency factors for pavement design, ranging from 1.28 to 2.52, particularly increasing for stations using single-line bending plate sensors. Pavement design datasets should span at least a year to reduce temperature effects and be checked for accuracy using the proposed steering axle load spectrum approach.

  • Impact of Brake Wear Particles on Eukaryotic Cell Viability and Associated Oxidative Stress Responses
    • Lina Trečiokaitė
    • Yurii Tsybrii
    • Oleksii Nosko
    • Lina Ragelienė
    2024 Pełny tekst Lubricants

    In this study, the cytotoxic effects of brake wear particles (≥250 nm ceramic/ceramic wear particles (CCWPs) and ≤100 nm ceramic/steel wear particles (CSWPs)) and 100 nm iron (III) oxide ultrafine particles (IOUFPs) on human lung carcinoma (A549) and Chinese hamster ovary (CHO) cells were investigated. Cell viability was determined using the MTT and Calcein AM methods. Oxidative stress was assessed by measuring reactive oxygen species (ROS), intracellular reduced glutathione (GSH), and malondialdehyde (MDA) concentrations under exposure to the above particles in the concentration range of 10–80 µg/mL. The initial assessments of CCWPs and CSWPs on the cell viability were performed after a 4-h exposure but later extended to 24 h to investigate the time-dependent of the cell viability and oxidative stress. MTT and Calcein AM assays indicated that the A549 cells are less susceptible to CCWPs and CSWPs than the CHO cells when exposed for both 4 h and 24 h. This study highlights that oxidative stress induced by CCWPs, CSWPs, and IOUFPs is cell-specific. While CCWPs did not affect glutathione (GSH) levels in the CHO cells, it significantly reduced GSH levels in A549 cells, with the exception of 80 µg/mL. Both CCWPs and CSWPs increased the lipid peroxidation in both cell types; however, the A549 cells demonstrated lower sensitivity to these treatments.

  • Impact of emerging pollutants mixtures on marine and brackish phytoplankton: diatom Phaeodactylum tricornutum and cyanobacterium Microcystis aeruginosa
    • Lilianna Sharma
    • Błażej Kudłak
    • Joanna Stoń-Egiert
    • Grzegorz Siedlewicz
    • Ksenia Pazdro
    2024 Pełny tekst SCIENCE OF THE TOTAL ENVIRONMENT

    Pharmaceuticals and ionic liquids (ILs) are emerging as significant micropollutants with environmental presence and potential ecological impacts. The possible simultaneous occurrence of these two groups of pollutants in aquatic environments raises complex challenges due to their diverse chemical properties and potential for interactive effects. Given the documented widespread presence of pharmaceuticals and the emerging concerns about ILs, the study aims to evaluate the adverse effects of binary mixtures of imidazolium ionic liquid IM1-8C (CN)3 and two representatives of pharmaceuticals: antibiotic oxytetracycline (OXTC) and metabolite carbamazepine 10,11 epoxide (CBZ-E) on the brackish cyanobacterium Microcystis aeruginosa and the marine diatom Phaeodactylum tricornutum during chronic exposure experiments. A comprehensive approach was employed, incorporating various endpoints including oxidative stress, chlorophyll a fluorescence, detailed photoprotective and photosynthetic pigment profiles of target microorganisms to assess modes of action and identify the mixture effects of the selected substances.

  • Impact of high-pressure processing on the bioactive compounds of milk - A comprehensive review
    • Shahida Anusha Siddiqui
    • Sipper Khan
    • Nur Alim Bahmid
    • Andrey Ashotovich Nagdalian
    • Seid Mahdi Jafari
    • Roberto Castro Munoz
    2024 Pełny tekst JOURNAL OF FOOD SCIENCE AND TECHNOLOGY-MYSORE

    High-pressure processing (HPP) is a promising alternative to thermal pasteurization. Recent studies highlighted the effectivity of HPP (400–600 MPa and exposure times of 1–5 min) in reducing pathogenic microflora for up to 5 logs. Analysis of modern scientific sources has shown that pressure affects the main components of milk including fat globules, lactose, casein micelles. The behavior of whey proteins under HPP is very important for milk and dairy products. HPP can cause significant changes in the quaternary (> 150 MPa) and tertiary (> 200 MPa) protein structures. At pressures > 400 MPa, they dissolve in the following order: αs2-casein, αs1-casein, k-casein, and β-casein. A similar trend is observed in the processing of whey proteins. HPP can affect the rate of milk fat adhering as cream with increased results at 100–250 MPa with time dependency while decreasing up to 70% at 400–600 MPa. Some studies indicated the lactose influencing casein on HP, with 10% lactose addition in case in suspension before exposing it to 400 MPa for 40 min prevents the formation of large casein micelles. Number of researches has shown that moderate pressures (up to 400 MPa) and mild heating can activate or stabilize milk enzymes. Pressures of 350–400 MPa for 100 min can boost the activity of milk enzymes by up to 140%. This comprehensive and critical review will benefit scientific researchers and industrial experts in the field of HPP treatment of milk and its effect on milk components.

  • Impact of information systems (IS) infusion on Open Government Data (OGD) adoption
    • Ricardo Matheus
    • Charalampos Harris Alexopoulos
    • Nina Rizun
    • Loukis Euripides
    • Stuti Saxena
    2024 Pełny tekst Digital Policy Regulation and Governance

    Purpose – This study aims to underline the possible influence of the moderator, information systems (IS) infusion, on Open Government Data (OGD) adoption and usage. Design/methodology/approach – Using the partial least squares-structural equation modeling methodological approach, the adapted unified theory of acceptance and use of technology (UTAUT) model has been used for understanding the role of themoderating variable, namely, IS infusion. Findings – Findings show that the moderating impact of IS infusion is positively significant with respect to the performance expectancy–behavioral intention relationship thereby bolstering the impact on users’ perception of OGD vis-a-vis work/academics performance and negatively significant for social influence–behavioral intention, information quality–behavioral intention, thereby clinching the fact that with the increased engagement and involvement of OGD in the everyday life of the user, the role of significant others and information quality gets least significant. Originality/value – Extant OGD-focused research has underscored the impact of different variables as far as OGD adoption and usage is concerned; the present study seeks to add on to the extant literature by understanding the implications of IS infusion on the adapted UTAUT model constructs and behavioral intention relationships

  • Impact of Macroeconomic Shocks on Financial Performance and Risk Management: A Case Study of LPP SA During the COVID-19 Pandemic and the Ukraine War
    • Ewelina Sokołowska
    • Mariusz Chmiewski
    • Anna Dziadkiewicz
    2024 Risks

    This study analyses the impact of two major macroeconomic shocks—the COVID-19 pandemic and the Ukraine war—on the financial stability of LPP SA, a leading apparel company in Poland and Central and Eastern Europe. This research uses the coefficient of variation to assess changes in financial volatility and evaluates the effectiveness of LPP SA’s risk management strategies. The findings reveal that, while the COVID-19 pandemic had a more destabilising effect on the company’s performance, the Ukraine war’s impact was mitigated by strategic diversification and resource reallocation. The study’s implications are relevant for risk management practices in the apparel industry and other consumer-driven sectors.

  • Impact of new, navigable canal through the Vistula spit on the hydrologic balance of the Vistula lagoon (Baltic Sea)
    • Roman Cieśliński
    • Izabela Chlost
    • Michał Szydłowski
    2024 JOURNAL OF MARINE SYSTEMS

    The object of research - the Vistula Lagoon is one of the two lagoons on the Polish coast, which is of great importance not only from an economic point of view, but also an environmental one. The purpose of the paper is to provide calculations on the current water balance for the Vistula Lagoon, before and after construction of a canal through the Vistula Spit. This is important because the construction of a new connection between the Vistula Lagoon and the Baltic Sea can result in changes in the lagoon's water balance, which in turn cause changes in the Vistula Lagoon biotic and abiotic environment. In addition, we wish to update the estimate of the water exchange between the Vistula Lagoon and the Baltic Sea through the Strait of Baltiysk and to estimate the exchange through the Vistula Spit canal after it is fully open. The main works consisted of researching source materials from various state institutions, which allowed to calculate the water balance of the Vistula Lagoon and perform mathematical modeling. These data include the amount of precipitation and evaporation, the amount of inflow from the catchment, the amount of inflow from polders, underground supply, the amount of inflow and outflow through the Strait of Baltiysk. The largest portion of the water received by a coastal lagoon comes from the adjacent ocean. In this case, it is about 75%. In addition, an array of catchment sources yields 20% of the studied lagoon's water. The Strait of Baltiysk constitutes the main outflow pathway for water exiting the Vistula Lagoon – close to 98% of outflow. Simulations have shown that the construction of the Nowy Swiat ship canal will not alter the water balance in the Vistula Lagoon to a meaningful extent. The problems that may emerge include those related to changes in the local biotic and abiotic environment due at the construction stage or in the period that follows resulting from the disturbance of highly polluted lagoon floor deposits. Thus it may be argued that the new canal is desirable from an economic or flood control point of view, but not from an environmental point of view.

  • Impact of SDN Controller’s Performance on Quality of Service
    • Sylwester Kaczmarek
    • Jacek Litka
    2024 Pełny tekst IEEE Access

    Software Defined Networking is a paradigm in network architecture; that is quickly becoming commonplace in modern telecommunication systems. It facilitates network customization for the requirements of different applications and simplifies the implementation of new services. Since its proposal, a significant evolution in its functionality has occurred. However, this development brought along problems of efficiency and performance, which are currently under research. A number of requirements has to be met, if Software Defined Networking is going to be the next step in the Next-Generation Networks progression. The central part of it – the SDN controller – has to put minimum strain on the system and provide performance which does not impede Quality of Service requirements. In this paper, the results of a research on SDN controller’s performance have been provided in the context of keeping up with flows’ QoS. For this, an emulated-physical research platform has been implemented. This research environment utilizes traffic generated accordingly to ITU-T recommendations to validate QoS parameters. The platform is given a thorough description. The results obtained from it take under consideration the implemented traffic sources, as well as the intensity of traffic handled by the controller and the traffic load of data plane links. Authors indicate that even without breaking the limitations set for delays in QoS, the impact of the controller workload is noticeable, which should be mitigated by applying appropriate resource control.