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Gdańsk University of Technology

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  • Filozofia sieci 5G - radioinformatyka i wirtualizacja. Część 2. Wirtualny system 5G.
    • Sławomir Gajewski
    • Małgorzata Gajewska
    2019 Przegląd Telekomunikacyjny + Wiadomości Telekomunikacyjne

    Przedstawiono najważniejsze właściwości sieci 5G z punktu widzenia istoty jej działania. Uporządkowano najistotniejsze pojęcia służące do opisu sieci 5G, zwłaszcza w kontekście rozwiązań softwarowych, wirtualizacji sieci oraz jej architektury fizycznej i funkcjonalnej. Wprowadzono i zdefiniowano wiele pojęć wynikających z nowej ery rozwoju radiokomunikacji, w tym pojęcie radioinformatyki, systemu radioinformatycznego, sieci radioinformatycznej. Uporządkowano i zdefiniowano główne elementy architektury sieci 5G zgodnie z przebiegiem standaryzacji oraz wskazano sposób integracji sieci 5G z 4G. Pierwsza część artykułu pt. Radioinformatyczny system 5G dotyczy w szczególności nowej nomenklatury koniecznej do przyjęcia w radiokomunikacji. Część druga pt. Wirtualny system 5G będzie natomiast dotyczyła problemu wirtualizacji w sieci 5G.

  • Finding small-width connected path decompositions in polynomial time
    • Dariusz Dereniowski
    • Dorota Osula
    • Paweł Rzążewski
    2019 Full text THEORETICAL COMPUTER SCIENCE

    A connected path decomposition of a simple graph $G$ is a path decomposition $(X_1,\ldots,X_l)$ such that the subgraph of $G$ induced by $X_1\cup\cdots\cup X_i$ is connected for each $i\in\{1,\ldots,l\}$. The connected pathwidth of $G$ is then the minimum width over all connected path decompositions of $G$. We prove that for each fixed $k$, the connected pathwidth of any input graph can be computed in polynomial-time. This answers an open question raised by Fedor V. Fomin during the GRASTA 2017 workshop, since connected pathwidth is equivalent to the connected (monotone) node search game.

  • First Copper(I) and Silver(I) Complexes Containing Phosphanylphosphido Ligands
    • Aleksandra Ziółkowska
    • Sandra Brauer
    • Łukasz Ponikiewski
    2019 Full text ZEITSCHRIFT FUR ANORGANISCHE UND ALLGEMEINE CHEMIE

    Three new complexes with phosphanylphosphido ligands, [Cu4{μ2-P(SiMe3)-PtBu}4](1), [Ag4{μ2-P(SiMe3)-PtBu2}4](2) and [Cu{η1-P(SiMe3)-PiPr2}2]–[Li(Diglyme)2] (3) were synthesized and structurally characterized by X-ray diffraction, NMR spectroscopy, and elemental analysis. Complexes 1 and 2 were obtained in the reactionsof lithium derivative of diphosphane tBu2P-P(SiMe3)Li·2.7THF withCuCl and [iBu3PAgCl]4, respectively. The X-ray diffraction analysis revealed that the complexes1 and 2 present macrocyclic, tetramericform with Cu4P4and Ag4P4core. Complex 3 was prepared in thereaction of CuCl with a different derivative of lithiated diphosphane iPr2P-P(SiMe3)Li·2(Diglyme). Surprisingly, the X-ray analysis of 3 revealed that in this reaction instead of the tetramer the monomericform, ionic complex [Cu{η1-P(SiMe3)-PiPr2}2]–[Li(Diglyme)2] was formed.

  • First report on echinocandin resistant Polish Candida isolates
    • Martyna Mroczyńska
    • Anna Brillowska-Dąbrowska
    2019 Full text Acta Biochimica Polonica

    Purpose: Candida spp. are ranked as one of the four major causative agents of fungal infections. The number of infections caused by Candida species resistant to fluconazole, which is applied as the first line drug in candidiasis treatment, increases every year. In such cases the application of echinocandin is necessary. Echinocandin susceptibility testing has become a routine laboratory practice in many countries due to the increasing frequency of clinical failures during treatment with these drugs. Methods: We performed anidulafungin, micafungin and caspofungin susceptibility testing according to the microdilution broth method on 240 Candida isolates collected in Polish hospitals. Results: We identified 12 isolates resistant to all echinocandins within 240 examined isolates. Moreover, 6 of the examined samples were identified as rare Candida species and among them we observed very high echinocandin MIC values. Conclusion: Our research proves that in Poland there is a problem of echinocandin resistance. Moreover, we identified two species of Candida which are rare causative agents of human infections, and there was no reported incidence of such infections in Poland until now.

  • Flexural buckling and post-buckling of columns made of aluminium alloy
    • Czesław Szymczak
    • Marcin Kujawa
    2019 EUROPEAN JOURNAL OF MECHANICS A-SOLIDS

    The paper concerns flexural buckling and initial post-buckling of axially compressed columns made of aluminium alloy described by the Ramberg-Osgood relationship. The non-linear differential equation of the problem is derived using the stationary total energy principle and the assumptions of classical beam theory within a finite range. The approximate analytical solution of the equation leading to the buckling loads and initial post-buckling equilibrium path is determined by means of the perturbation approach. Numerical examples dealing with simply supported and clamped I-columns are presented, the effect of the material non-linearity on the critical loads and initial post-buckling behaviour in comparison to linear one is discussed too. The analytical results are compared with the FEM solutions to present a good agreement.

  • Flood Security Strategy - Case Studies from Gdańsk Region
    • Andrzej Lewandowski
    • Piotr Kowalski
    • Wojciech Szpakowski
    2019

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  • Floodplain inundation Mapping using SAR Scattering Coefficient Thresholding and Observed Discharge Data
    • Tomasz Berezowski
    • Tomasz Bieliński
    • Jakub Osowicki
    2019 Full text

    Inundation area time series are important for wetlands monitoring and hydrological model validation. This study is conducted in Biebrza floodplain, which is a natural wetland with complex inundation generation processes. In order to map 2014-2018 series of inundation in the floodplain we test our automatic thresholding method on Sentinel 1 data. The threshold value is optimized using correlation of the inundation area with observed discharge at the floodplain outlet. The inundation maps match well the MODIS 500m reflectance data used as a reference, whereas, the total inundated area per Sentinel 1 image match well the observed discharge pattern. Unfortunately, this approach was unable to identify inundation in remote parts of the floodplain, what may have few reasons and needs further investigation.

  • Flow Boiling in Minigap in the Reversed Two-Phase Thermosiphon Loop
    • Michał Klugmann
    • Paweł Dąbrowski
    • Dariusz Mikielewicz
    2019 Full text ENERGIES

    The paper presents the results of experimental investigations of a model of a heat exchanger featuring a minigap, which is perceived as an evaporator for an inverted thermosiphon. The system works with a single component test fluid. The tested evaporator generates pumping power in the test loop in a way similar to the mammoth pump. The tests regarded a module of the heat exchanger, consisting of a hot leg and a cold leg with the width by the length of 0.1 × 0.2 m, heated by a uniform heat flux. In the tests, the minigaps of 1, 2 and 3 mm were formed. Two fluids, namely, distilled water and ethanol, were tested in the facility. Two-phase flow structures for both working fluids and various operational parameters, together with comprehensive visualization material, are presented. The specifics of pressure changes and its influence on operating parameters and flow structure are discussed.

  • Flow maldistribution and its mitigation in mini heat exchangers
    • Paweł Dąbrowski
    • Michał Klugmann
    • Dariusz Mikielewicz
    2019

    In the present paper, a detailed numerical investigation has been carried out to analyze the flow maldistribution in 50 parallel 1 mm x 1 mm rectangular minichannels and 1 mm depth minigap section with rectangular, trapezoidal, triangular or concave mani-folds in Z-type flow configuration (16 different cases). The working medium was ethanol and the mass flow rate was 5×10-4 kg/s. Both sections was heated from the bottom side. Heat flux of 10 000 W/m2 and 5 000 W/m2 was applied to the minichannel and minigap section respectively. It provides an equal heat flow rate of about 50 W for both types of the sections. A novel approach for the mitigation of non-uniformity has been proposed introducing threshold at the entrance of the minigeometry section. The maldistribution coefficient can be reduced about twice in the minigap section or about three times in the minichannel section with the 0.5 mm threshold as compared to the conventional arrangement without threshold. Authors analyzed velocity profile and temperature profile over the heat exchanger’s surface. Reduction of maldistribution results in lower maximum temperature over the surface. The distribution is more uniform in minichannel section than in minigap section. This is due to a two-dimensional flow over a minigap in comparison to one-dimensional flow in channels. To obtain uniform distribution of fluid and hence uniform temperature profile, flow should be stabilized al-ready at the inlet manifold, at the entrance to the minichannel or minigap section.

  • Folate/homocysteine metabolism and lung cancer risk among smokers
    • Anna Stanisławska-Sachadyn
    • Joanna Borzyszkowska
    • Michał Krzemiński
    • Alicja Janowicz
    • Rafał Dziadziuszko
    • Jacek Jassem
    • Witold Rzyman
    • Janusz Limon
    2019 Full text PLOS ONE

    Background: Folate and homocysteine are involved in DNA synthesis and methylation processes, which are deregulated during carcinogenesis. Objectives: The aim of this study was to assess the relationship between folate/homocysteine concentrations, the functional polymorphisms of folate/homocysteine genes and lung cancer risk among cigarette smokers. Study design: The study included 132 lung cancer patients and 396 controls from northern Poland, matched by sex, age and smoking status. The median cigarette pack-years of smoking among both cases and controls was 30.0. Serum, red blood cell (RBC) folates and serum homocysteine concentrations were measured. The genotypes in selected polymorphic sites of the MTHFR, CBS, SHMT1, MTHFD1, MTRR, MTR, TYMS DHFR, TCN2, and SLC19A1 genes were determined. All study participants underwent scanning with low-dose computed tomography. Results: Serum folate concentrations above the median (> 17.5 nmol/l among the healthy controls) were associated with an increased lung cancer risk (odds ratio [OR], 1.54, 95% confidence intervals [CI], 1.04-2.29, P= 0.031). An analogous trend was observed when the population was analysed after subdivision according to RBC folate concentrations, that is, above a value of 506.5 nmol/l (OR, 1.53; 95% CI, 0.95-2.47; P=0.084). Additionally, in a subset of women, an increased risk of lung cancer development was associated with the SLC19A1 c.80AA genotype (c.80AA versus GG OR, 3.14; 95% CI, 1.32-7.46; P= P=0.010). Conclusion: These results suggest that, in the population consisting of heavy smokers, high folate levels add to the cancerogenic effect of smoking.

  • Follow the Light. Where to search for useful research information
    • Karolina Zielińska-Dąbkowska
    2019 Full text ARC Lighting In Architecture

    Architectural Lighting Design (ALD) has never been a standalone professional discipline. Rather, it has existed as the combination of art and the science of light. Today, third generation lighting professionals are already creatively intertwining these fields, and the acceleration in scientific, technological and societal studies has only increased the need for reliable multidisciplinary information. Therefore, a thorough re-examination of all aspects of ALD and how it relates to those particular changes is an urgent necessity. Further research is required to develop a new body of knowledge about ALD so that lighting professionals can improve their expertise in the field and receive better remuneration for their complex work. In the near future, we should be aiming for professional recognition as experts and join other recognised professions such as: architects, doctors, dentists, lawyers, engineers etc. While lighting designers (LD) need to constantly update and reexamine their knowledge, they face two dilemmas. First, WHERE should they search to obtain useful information on lighting in related fields? And secondly, HOW should they successfully evaluate the viability of this information in a time of “Google-isation”, Wikipedia, “lobbying” and data manipulation.

  • Force transfer and stress distribution in short cantilever deep beams loaded throughout the depth with a various reinforcement
    • Anna Kopańska
    • Krystyna Nagrodzka-Godycka
    2019

    Deep beams used as the main reinforced concrete structural elements which taking over the load and stiffening construction are often found in high-rise buildings. The architecture of these buildings is sometimes sophisticated and varied, arouse the admiration of the majority of recipients, and thus causing an engineering challenge to correctly design the structural system and force transfer. In such structures is important to shape the reinforcement in order to make the best use of reinforcing steel for taking over the load and minimize the crack widths. Despite the wide use of these elements, they are still not covered by the relevant design codes. In the current technical literature there is little information on the dimensioning of reinforced concrete cantilever deep beams or deep beams with overhangs and only few based on experimental research. This paper presents the results of experimental investigations of two reinforced concrete cantilever deep beams with shear slenderness lk / H = 0.3 under static load distributed on the entire height. The research elements were part of the spatial reinforced concrete deep beam systems, consisting of a transversal deep beam and suspended on it the longitudinal deep beam with cantilever. Reinforced concrete deep beam joints had various reinforcements. The article presents results on steel effort and force distribution in the reinforcement of short cantilever deep beam indirectly loaded. The effectiveness of the mixed reinforcement in both tested cantilever deep beams, as referred to the design recommendation proposed in the published papers is also verified. © Federation Internationale du Beton (fib) - International Federation for Structural Concrete, 2019.

  • FORECASTING EXCHANGE RATES IN THE PROCESS OF THE ASSESSMENT OF CONSUMER RISK BANKRUPTCY IN CENTRAL EUROPE
    • Tomasz Korol
    2019

    This paper focuses on the issue of forecasting the fluctuation of exchange rates as part of the early warning system against the risk of consumer bankruptcy. The author identified the main macroeconomic factors affecting the level of bankruptcies for households in Poland. The fluctuation of exchange rates, which directly affects the deterioration of the economic situation of borrowers who have opened credit accounts in a foreign currency and indirectly affects the cost of living of all consumers in the country, is one of the significant macroeconomic factors. That is why the main objective of the presented research is to investigate the effectiveness of fuzzy sets in predicting the volatility of two currency pairs (PLN/CHF and PLN/USD). The models created will be part of a system of models aimed at forecasting the risk of consumer bankruptcy in Poland. The results demonstrate the high predictive properties of fuzzy sets in forecasting the volatility of analyzed currency pairs.

  • Formalno-prawne uwarunkowania rozwoju mieszkalnictwa w Polsce w aspekcie eksploatacji mieszkalnych jednistek pływających
    • Emilia Miszewska
    • Maciej Niedostatkiewicz
    2019

    Artykuł zawiera analizę sytuacji prawnej obiektów jakimi są Domy Na Wodzie oraz konsekwencji jakie powodują dla właścicieli aktualne zapisy najważniejszych Ustaw z nimi związanych tzn.: ustawy Prawo budowlane, ustawy o gospodarce nieruchomościami, Kodeksu cywilnego oraz Prawa wodnego. W pracy opisano światowe trendy osadnictwa na wodzie i porównano do sytuacji mieszkalnictwa na wodzie w Polsce. Na podstawie doświadczeń innych krajów oraz w oparciu o przepisy krajowe, opracowano i zaproponowano autorską definicję dla Domów Na Wodzie, (DNW) nazwanych przez autorów Mieszkalnymi Jednostkami Pływającymi (MJP). Ponadto podjęto próbę usystematyzowania wymagań i rozwiązań części problemów formalno-prawnych jakie w fazie eksploatacji dotyczą właścicieli MJP.

  • Formation of Protein Networks between Mucins: Molecular Dynamics Study Based on the Interaction Energy of the System
    • Natalia Kruszewska
    • Piotr Bełdowski
    • Piotr Weber
    • Steven Yuvan
    • Marcin Drechny
    • Marcin Kośmieja
    2019 Full text ENERGIES

    Molecular dynamics simulations have been performed for a model aqueous solution of mucin. As mucin is a central part of lubricin, a key component of synovial fluid, we investigate its ability to form cross-linked networks. Such network formation could be of major importance for the viscoelastic properties of the soft-matter system and crucial for understanding the lubrication mechanism in articular cartilage. Thus,the inter- and intramolecular interaction energies between the residues of mucin are analyzed. The results indicate that the mucin concentration significantly impacts its cross-linking behavior. Between 160 g/L and 214 g/L, there seems to be a critical concentration above which crowding begins to alter intermolecular interactions and their energies. This transition is further supported by the mean squared displacement of the molecules. At a high concentration, the system starts to behave subdiffusively due to network development. We also calculate a sample mean squared displacement and p-variation tests to demonstrate how the statistical nature of the dynamics is likewise altered for different concentrations.

  • Fotokatalityczna degradacja zanieczyszczeń środowiskowych
    • Joanna Mioduska
    • Anna Zielińska-Jurek
    • Jan Hupka
    2019 Nowa Energia

    Fotokataliza uznawana jest za metodę z rosnącym potencjałem do usuwania zanieczyszczeń organicznych i nieorganicznych - zarówno z fazy wodnej, jak i gazowej. Liczba publikacji z ostatnich pięciu lat związana z tematyką fotokatalizy osiąga ponad 4000 rocznie, wg bazy danych Web of Science (2019 r.). Szczególny potencjał fotokatalizy tkwi w możliwości usuwania zanieczyszczeń uporczywie zalegających w środowisku, których źródłem są ścieki przemysłowe i komunalne.

  • Fractional Order Circuit Elements Derived from Electromagnetism
    • Tomasz Stefański
    • Jacek Gulgowski
    2019

    In this paper, derivations of fractional-order (FO) circuit-element equations from electromagnetism are presented. Whilst many papers are devoted to FO modelling of electrical circuits, there are no strong foundations for such an approach. Therefore, we investigate relations between the FO electromagnetism and the FO circuit theory. Our derivations start from quasi-static (QS) approximations of Maxwell's equations in media with FO constitutive relations. Hence, FO lumped-element equations are derived which are supported by an approximate applicability condition. If the FO capacitor/inductor satisfies the derived condition, then the energy of the magnetic/electric field is negligible in comparison to the energy of the electric/magnetic field in the considered FO element. Then, we demonstrate that FO lumped-element parameters can be derived assuming the equality of electromagnetic power flowing into the circuit element and calculated as the current and voltage product. The obtained results support researchers and engineers employing FO modelling in electrical and electronics engineering.

  • Fracture evolution in concrete compressive fatigue experiments based on X-ray micro-CT images
    • Łukasz Skarżyński
    • Ireneusz Marzec
    • Andrzej Tejchman-Konarzewski
    2019 Full text INTERNATIONAL JOURNAL OF FATIGUE

    Artykuł omawia ewolucje pękania w betonie podczas cyklicznego ściskania betonu. Przestrzenną ewolucję pękania zobrazowano stosując mikro-tomograf rentgenowski. Zdjęcia wykonano dla różnych cykli zmęczeniowych. Wyniki porównano z testami monotonicznymi. Jakościowa ewolucja objętości pękania ze wzrostem zmęczeniowego zniszczenia pokazała silnie nieliniowy kształt.

  • Frakcje azotu organicznego w wywarze gorzelnianym
    • Anna Wilińska
    • Krzysztof Czerwionka
    2019

    Wywar gorzelniany jest produktem ubocznym w procesie wytwarzania surowego spirytusu. W Polsce na jeden litr wyprodukowanego spirytusu powstaje od 9 do 14 litrów tego odpadu. Charakteryzuje się on wysokim ładunkiem ChZT oraz azotu ogólnego, występującego głównie w formie azotu organicznego. Przy wysokiej produkcji alkoholu stwarza to poważne problemy w zagospodarowaniu całej ilość powstającego wywaru. W pracy przedstawiono wyniki analiz składu pięciu wywarów gorzelnianych oraz odcieków powstających podczas ich odwirowania. Charakterystyka wywaru gorzelnianego oraz odcieków uzależniona była od składu oraz zawartości suchej masy wsadu wykorzystywanego w gorzelniach do produkcji alkoholu. W odciekach z odwirowania wywarów stwierdzono wysoki udział frakcji rozpuszczonej zawiązków organicznych (84 do 95% ChZT) oraz azotu organicznego (od 81 do 93% azotu ogólnego). W odniesieniu do frakcji azotu organicznego stwierdzono, że dla trzech z pięciu odcieków zdecydowanie dominowała frakcja rozpuszczona (DON), która stanowiła od 75 do 80% azotu organicznego. Natomiast dla dwóch pozostałych odcieków udział tej frakcji spadł do 40-50%, przy jednoczesnym wzroście udziału frakcji koloidalnej do 30-40%. Nie stwierdzono statystycznie istotnych zależności pomiędzy stężeniem frakcji DON i CON w odciekach, a innymi badanymi parametrami jakości odcieków lub wywarów.

  • Framework of an Evolutionary Multi-Objective Optimisation Method for Planning a Safe Trajectory for a Marine Autonomous Surface Ship
    • Rafał Szłapczyński
    • Mohammad Ghaemi
    2019 Full text Polish Maritime Research

    This paper represents the first stage of research into a multi-objective method of planning safe trajectories for marine autonomous surface ships (MASSs) involved in encounter situations. Our method applies an evolutionary multi-objective optimisation (EMO) approach to pursue three objectives: minimisation of the risk of collision, minimisation of fuel consumption due to collision avoidance manoeuvres, and minimisation of the extra time spent on collision avoidance manoeuvres. Until now, a fully multi-objective optimisation has not been applied to the real-time problem of planning safe trajectories; instead, this optimisation problem has usually been reduced to a single aggregated cost function covering all objectives. The aim is to develop a method of planning safe trajectories for MASSs that is able to simultaneously pursue the three abovementioned objectives, make decisions in real time and without interaction with a human operator, handle basic types of encounters (in open or restricted waters, and in good or restricted visibility) and guarantee compliance with the International Regulations for Preventing Collisions at Sea. It should also be mentioned that optimisation of the system based on each criterion may occur at the cost of the others, so a reasonable balance is applied here by means of a configurable trade-off. This is done throughout the EMO process by means of modified Pareto dominance rules and by using a multi-criteria decision-making phase to filter the output Pareto set and choose the final solution.

  • FROM HARVESTING TO DISTILLATION - EFFECT OF ANALYTICAL PROCEDURES ON THE YIELD AND CHEMICAL COMPOSITION OF RHODODENDRON TOMENTOSUM (LEDUM PALUSTRE) ESSENTIAL OIL
    • Anna Jesionek
    • Bożena Zabiegała
    • Adam Bucinski
    • Maria Łuczkiewicz
    2019 Full text Acta Poloniae Pharmaceutica - Drug Research

    Rhododendron tomentosum possesses the anti-inflammatory, analgesic and antimicrobial properties, determined by the chemical composition of its essential oil. The effects of place (Miszewko, Lubichowo) and time of harvesting (June, November) as well as drying (air-drying, oven-drying, freeze-drying) and isolation (in Deryng, Clevenger and Likens-Nickerson apparatus) procedures on the yield and quality of R. tomentosum essential oil were studied. Ledol (8.1-14.4%), palustrol (6.9-13.0%) and γ-terpineol (8.5-9.1%) predominated in the plants collected from Miszewko, while γ-terpineol (11.8-22.2%), p-cymene (5.3-12.6%) and geranyl acetate (5.7-7.5%) prevailed in the biomass from Lubichowo. The shoots produced more volatiles in the flowering phase than at the end of the vegetation. Oven-drying at 30OC with controlled air flow was suggested as the quick dehydration method. Hydrodistillation in Deryng and Clevenger apparatus resulted in comparatively high essential oil yield (about 1%). All studied drying and distillation methods did not influence significantly the general profile of R. tomentosum essential oil

  • From structure to luminescence investigation of oxyfluoride transparent glasses and glass-ceramics doped with Eu3+/Dy3+ ions
    • Michalina Walas
    • Marta Lisowska
    • Tomasz Lewandowski
    • Ana I. Becerro
    • Marcin Łapiński
    • Anna Synak
    • Wojciech Sadowski
    • Barbara Kościelska
    2019 JOURNAL OF ALLOYS AND COMPOUNDS

    Glasses and glass-ceramics with nominal composition 73 TeO2– 4BaO– 3Bi2O3–18SrF2-2RE2O3 (where RE = Eu, Dy) have been synthesized by conventional melt-quenching technique and subsequent heat treatment at 370 °C for 24 h in air atmosphere. Various Eu3+ to Dy3+ molar ratio have been applied to investigate luminescence properties in both glass and glass-ceramic matrices. Especially, white light emission through simultaneous excitation of Eu3+ and Dy3+ has been studied in detail. Influence of crystalline SrF2 phase on luminescence kinetics has been determined by luminescence decay time measurements. Presence of crystalline SrF2 phase has been confirmed by X-ray diffraction technique XRD and transmission electron microscopy TEM. X-ray photoelectron spectroscopy XPS and Fourier-transform infrared spectroscopy FTIR have been applied to get further insight into structural properties of glass and glass-ceramic materials. Color tunable white light emission has been obtained using UV excitation. Influence of the SrF2 crystallization on luminescence properties of prepared materials have been described in detail. Moreover, luminescence properties and especially emission color dependence on the Eu3+ to Dy3+ molar ratio have been exhaustively studied. Color-tunable white light emission has been observed as a result of simultaneous radiative transition of both, Eu3+ and Dy3+ ions when applying UV excitation. Judd – Ofelt and other optical parameters have been calculated based on luminescence emission spectra. Achieved results confirm that tellurite glass-ceramics containing SrF2 nanocrystals are good hosts for RE3+ ions and they can be considered as new phosphors for white light emitting diodes WLEDs.

  • Full scale CFD seakeeping simulations for case study ship redesigned from V-shaped bulbous bow to X-bow hull form
    • Karol Niklas
    • Hanna Pruszko
    2019 APPLIED OCEAN RESEARCH

    Increasing propulsion efficiency, safety, comfort and operability are of the great importance, especially for small ships operating on windy sites like the North Sea and the Baltic Sea. Seakeeping performance of ships and offshore structures can be analysed by different methods and the one that is becoming increasingly important is CFD RANS. The recent development of simulation techniques together with rising HPC accessibility enables performance of advanced seakeeping simulations for ships in a full scale. The paper presents CFD seakeeping analysis for a case study vessel in two variants: V-shaped bulbous bow hull form (as built) and innovative hull form (X-bow type). The study presents the influence of redesigning the ship on selected seakeeping aspects. The advanced CFD model, with the application of overset mesh technique, was described in detail. Selected numerical results were validated on the basis of experimental testing in a towing tank and showed good agreement. The approach demonstrated here of performing the CFD seakeeping simulations for the analysis of ship performance in a full scale and close to real loading conditions has direct application to the design process as well as in determination of optimal operational parameters of any ship.

  • Full-scale CFD simulations for the determination of ship resistance as a rational, alternative method to towing tank experiments
    • Karol Niklas
    • Hanna Pruszko
    2019 OCEAN ENGINEERING

    Results of ship resistance predictions obtained from towing tank experiments are affected by the method used to extrapolate from a model scale to a ship scale. Selection of method to determine a form factor is subjective and the extrapolation method is accurate for typical hull forms. For innovative hull forms the proper method for calculating the form factor is questionable. Moreover, the influence of the extrapolation method can be equally as important as the influence of a redesigned hull form itself. The paper presents novel numerical and experimental methods used to predict ship's total resistance in calm water. The results determined by towing tank experiments, full-scale CFD simulations and ship's sea trial measurements were compared. Depending on the method used, the determined form factor differed by 19%. As a result, the predicted calm water resistance varied from −6% to 11% relatively to sea trials data. For innovative hull forms in particular, full-scale CFD simulations should support the towing tank method. The results calculated by full-scale CFD varied from −10% to 4% relatively to sea trials data depending on the assumptions on hull roughness and turbulence model. The towing tank testing and full-scale CFD simulations can provide similar accuracy.

  • Fully Adaptive Savitzky-Golay Type Smoothers
    • Maciej Niedźwiecki
    • Marcin Ciołek
    2019 Full text

    The problem of adaptive signal smoothing is consid-ered and solved using the weighted basis function approach. Inthe special case of polynomial basis and uniform weighting theproposed method reduces down to the celebrated Savitzky-Golaysmoother. Data adaptiveness is achieved via parallel estimation.It is shown that for the polynomial and harmonic bases andcosinusoidal weighting sequences, the competing signal estimatescan be computed in both time-recursive and order-recursive way.

  • Functional safety and cyber security analysis for life cycle management of industrial control systems in hazardous plants and oil port critical infrastructure including insurance
    • Kazimierz Kosmowski
    • Dariusz Gołębiewski
    2019 Full text Journal of Polish Safety and Reliability Association, Summer Safety and Reliability Seminars

    This report addresses selected methodological aspects of proactive reliability, functional safety and cyber security management in life cycle of industrial automation and control systems (IACS) in hazardous plants and oil port critical installations based on the analysis of relevant hazards / threats and evaluation of related risks. In addition the insurance company point of view has been also considered, because nowadays the insurer, interested in decreasing risks to be insured, offers the expertise how to limit effectively risks in life cycle from the design conceptual stage of hazardous plant, through its reliable and safe operation, until decommissioning. Therefore, the risk evaluation model for insurance related decision making for the period considered, e.g. one year, should be plant specific with some predictive properties due to changing environment and business conditions, and usually considerable uncertainty involved. The objective is to evaluate and mitigate risks, and control them proactively, through undertaking appropriate activities within a process based management system according to elaborated policy and strategy that includes organisational and technical aspects, including preventive maintenance activities of sensitive equipment and updating in time the training programmes. Careful evaluating and controlling risks is also crucial for the insurance company. Basic activities of the risk engineers and underwriters in the insurance process are outlined in the context of identified hazards/threats and defined factors that significantly influence risks to be considered in evaluating the insurance premium in the context of terms and conditions specified.

  • Functionalized polyolefins, synthesis application and industrial relevance
    • Lidia Jasińska-Walc
    • Rob Duchateau
    • Miloud Bouyahyi
    2019

    Polymers play a key role in our modern life full of technical advances and a continuous request for new materials with tailored properties for a low price. Their excellent mechanical properties, good processability, chemical stability and low price make polyolefins the polymers of choice for most commodity and some more specialized applications. As a result, polyolefins account for over 65% of the total world demand of plastic materials. However, the major drawback of polyolefins is their lack of functionality, which results in low adhesion with other materials such as inorganic fillers, metals or other polymers. The availability of well-defined functionalized polyolefins will certainly increase the application window of polyolefins even more. Incorporation of polar functionalities into the polyolefins is believed to enhance the adhesive properties of the polymers and numerous reports describe the synthesis of such products either by reactive extrusion or by catalysis.[1] Yet, little is known about the actual properties of these materials and their potential applications. Many questions remain, like: Do functionalized polyolefins indeed show improved adhesion to polar substrates or improved paintability? What functionality level is required to obtain satisfying adhesive properties? How do these functionalities affect the polyolefin properties? Are there other applications for functionalized polyolefins than just improved adhesion? Over the last years, our group has evaluated the synthesis and material properties of functionalized polyolefins prepared by both catalysis and reactive extrusion and we have explored potential applications of such materials. This contribution will give a clear overview of the potential of functionalized polyolefins and the various challenges that have to be overcome to produce these products in a commercially viable manner. Issues like potential catalyst poisoning by functionalized comonomers and reactor fouling during in-reactor functionalization and differences in material properties of functionalized polyolefins obtained by reactive extrusion and in-reactor functionalization will be addressed. With some striking examples, it will be demonstrated that functionalized polyolefins can be used in applications usually reserved for specialty polymers.

  • Funkcja drenażowa geosyntetyków
    • Remigiusz Duszyński
    2019 Geoinżynieria, Drogi, Mosty, Tunele

    Spośród wielu funkcji geosyntetyków, które powszechnie znajdują zastosowanie w budownictwie jedną z istotniejszych jest funkcja drenażowa. Zapewnienie długotrwałego, niezawodnego funkcjonowania drenażu wymaga przyjęcia odpowiedniego geokompozytu drenażowego. To złożone zagadnienie zostało przedstawione w poniższym artykule.

  • FUNKCJONALIZOWANE ADSORBENTY WĘGLOWE DO EFEKTYWNEGO USUWANIA JONÓW METALI Z WODY
    • Małgorzata Nadolska
    • Kamila Sadowska
    2019 Full text

    W niniejszej pracy zbadano skuteczność adsorpcyjnego usuwania jonów Hg2+, Sr2+ z roztworów wodnych, z wykorzystaniem funkcjonalizowanych materiałów węglowych. Jako adsorbenty zastosowano nanorurki węglowe, tlenek grafenu oraz węgiel aktywny. Oprócz często stosowanej praktyki jaką jest wykorzystanie materiałów węglowych które na swojej powierzchni zawierają tlenowe grupy funkcyjne, zaproponowano aby na powierzchnię materiałów węglowych wprowadzić dodatkowe grupy funkcyjne w postaci grup fosfonowych. W celu określenia rodzaju powierzchniowych grup funkcyjnych oraz oszacowanie ich ilości (a następnie określenia ich wpływu na zdolności adsorpcyjne jonów Hg2+, Sr2+), materiały scharakteryzowano za pomocą metod spektroskopowych (FTIR, Raman), TGA oraz SEM.

  • Further development of the poroelastic road surface within the new Polish project SEPOR
    • Piotr Mioduszewski
    • Jerzy Ejsmont
    • Grzegorz Ronowski
    • Stanisław Taryma
    2019

    Road surfaces have a direct impact on noise generated by rolling tyres, the main and dominant source of noise of moving vehicles. Road surface texture, porosity and stiffness/elasticity govern the pavement contribution to tyre/road noise the most. An experimental PoroElastic Road Surface (PERS) is a wearing course with a high content of interconnected voids (pores) and with an elastic behavior due to the use of small particles of rubber as the main aggregate. It was already proved, that using that type of pavement, a road traffic noise reduction up to 12 dB can be achieved. The new project SEPOR founded by the Polish National Centre for Research and Development has started in 2018 aiming in further development of poroelastic road surface. Its main goal is to enhance durability of PERS by optimization of mix composition, improvement of the production process, increasing the interlayer bonding strength and to optimize noise reduction and skid resistance. Experimental test sections will be constructed within a trafficked road and tested for noise, rolling resistance, skid resistance and fire suppression properties. The paper presents the results of noise and rolling resistance measurements performed on a pilot small-scale test section of PERS built on a construction yard.

  • Galvanostatic impedance measurements for the efficient adsorption isotherm construction in corrosion inhibitor studies
    • Jacek Ryl
    • Joanna Wysocka
    • Mateusz Cieślik
    • Stefan Krakowiak
    • Paweł Ślepski
    2019

    We present an approach towards an accurate and time-efficient adsorption isotherm determination to evaluate the corrosion inhibitor interaction in electrolytic environments. The approach is based on dynamic impedance spectroscopy measurements in galvanostatic mode (g-DEIS). The studied corrosion inhibitor is continuously injected between the secondary cell and the corrosion cell. The efficiency corresponding to instantaneous inhibitor concentration is determined based on the charge transfer resistance. The galvanostatic mode ensures lack of artificial polarization component resulting from alteration of the corrosion potential by studied inhibitor. Analysis of the double-layer capacitance course of changes delivers information on the inhibitor concentration sufficient to form monolayer of the inhibitor, representing boundary conditions for Langmuir adsorption model validity. Its utility was confirmed using ellipsometry while the g-DEIS studies were cross-verified by other electrochemical tools (potentiodynamic polarization, EIS) as well as XPS and microscopic analyses. The discussed approach was first used to investigate the corrosion inhibition efficiency of various carboxylic acids towards aluminium alloys in alkaline environments, although more recently it was tested to evaluate the efficiency of complex inhibitor extracts, such as bee pollen inhibition efficiency.

  • Gas Turbine Cycle with External Combustion Chamber for Prosumer and Distributed Energy Systems
    • Dariusz Mikielewicz
    • Krzysztof Kosowski
    • Karol Tucki
    • Marian Piwowarski
    • Robert Stępień
    • Olga Orynycz
    • Wojciech Włodarski
    2019 Full text ENERGIES

    The use of various biofuels, usually of relatively small Lower Heating Value (LHV), affects the gas turbine efficiency. The present paper shows that applying the proposed air by-pass system of the combustor at the turbine exit causes tan increase of efficiency of the turbine cycle increased by a few points. This solution appears very promising also in combined gas/steam turbine power plants. The comparison of a turbine set operating according to an open cycle with partial bypassing of external combustion chamber at the turbine exit (a new solution) and, for comparison, a turbine set operating according to an open cycle with a regenerator. The calculations were carried out for different fuels: gas from biomass gasification (LHV = 4.4 MJ/kg), biogas (LHV = 17.5 MJ/kg) and methane (LHV = 50 MJ/kg). It is demonstrated that analyzed solution enables construction of several kW power microturbines that might be used on a local scale. Such turbines, operated by prosumer’s type of organizations may change the efficiency of electricity generation on a country-wide scale evidently contributing to the sustainability of power generation, as well as the economy as a whole.

  • Gas‐Phase Removal of Indoor Volatile Organic Compounds and Airborne Microorganisms Over Mono‐ and Bimetal‐Modified (Pt, Cu, Ag) Titanium(IV) Oxide Nanocomposites
    • Izabela Wysocka
    • A. Markowska-Szczupak
    • Piotr Szweda
    • Jacek Ryl
    • Maya Endo-Kimura
    • Kowalska Ewa
    • Grzegorz Nowaczyk
    • Anna Zielińska-Jurek
    • Agata Markowska-Szczupak
    2019 INDOOR AIR

    The photocatalytic deactivation of volatile organic compounds and mold fungi using TiO2 modified with mono‐ and bimetallic (Pt, Cu, Ag) particles is reported in this study. The mono‐ and bimetal‐modified (Pt, Cu, Ag) titanium(IV) oxide photocatalysts were prepared by chemical reduction method and characterized using XRD, XPS, DR/UV‐Vis, BET and TEM analysis. The effect of incident light, type and content of mono‐ and bimetallic nanoparticles deposited on titanium(IV) oxide was studied. Photocatalytic activity of as‐prepared nanocomposites was examined in the gas phase using LEDs array. High photocatalytic activity of Ag/Pt‐TiO2 and Cu/Pt‐TiO2 in the reaction of toluene degradation resulted from improved efficiency of interfacial charge transfer process, which was consistent with the fluorescence quenching effect revealed by photoluminescence (PL) emission spectra. The photocatalytic deactivation of Penicillium chrysogenum, a pathogenic fungi present in the indoor environment, especially in a damp or water‐damaged building using mono‐ and bimetal‐modified (Pt, Cu, Ag) titanium(IV) oxide was evaluated for the first time. TiO2 modified with mono‐ and bimetallic NPs of Ag/Pt, Cu and Ag deposited on TiO2 exhibited improved fungicidal activity under LEDs illumination than pure TiO2.

  • Gate Driver with Overcurrent Protection Circuit for GaN Transistors
    • Paweł Derkacz
    • Piotr Musznicki
    2019 Full text Przegląd Elektrotechniczny

    The improvement of the gate driver for GaN transistor is presented in this paper. The proposed topology contains the overcurrent protectionwith the two-stage turning off and independent control of turn on and off time of the GaN transistor. The operation of driver and its application in thehalf-bridge converter are described using both simulation and prototype measurements. The overcurrent protection was tested in Double Pulse Test(DPT) conditions.

  • Gdańsk oczami Irlandzkich i Polskich Artystów Plastyków. Krenz J.: Cykl 7 akwarel i pasteli. Zimowy Gdańsk
    • Jacek Krenz
    2019

    Międzynarodowa wystawa zbiorowa, poplenerowa: Gdańsk oczami Irlandzkich i Polskich Artystów Plastyków. Galeria Sztuki Domu Aktora w Gdańsku. Przez kilka grudniowych dni artyści plastycy z Irlandii i Polski malowali zimowy Gdańsk. Stronę irlandzką reprezentowali: Jonathan Brennan, Katherine St.Angelo, Esther O’Kelly, Joanna Mules, Marcus Patton. Polscy uczestnicy: Magdalena Nowacka-Kolano, Anna Schumacher, Krzysztof Ludwin i Komisarz Pleneru - Jacek Krenz.

  • Gdańska Międzynarodowa Szkoła Letnia na WETI
    • Marek Kubale
    2019 Pismo PG

    W dniach 6-12 lipca 2019 roku Katedra Algorytmów i Modelowania Systemów zorganizowała 3. Międzynarodową Szkołę Letnią poświęconą algorytmom dla problemów optymalizacji dyskretnej.

  • General, Mild, and Metal-Free Functionalization of Indole and Its Derivatives Through Direct C3-Selenylation
    • Adam Hałuszczuk
    • Natalia Babul
    • Łukasz Nierzwicki
    • Witold Przychodzeń
    2019 Full text EUROPEAN JOURNAL OF ORGANIC CHEMISTRY

    A very mild method for the introduction of functionalized alkylselenyl group at C-3 position of the indole ring was developed. The proposed procedure consists of an electrophilic substitution of indole and its derivatives with bis(O,O-diisopropoxyphosphorothioyl) diselenide and subsequent cleavage of the P–Se bond with tetrabutylammonium fluoride in the presence of various electrophilic reagents. This method can be successfully applied, inter alia, for the preparation of amino acid and glucoside derivatives of 3-selenoindole.

  • Generalized Savitzky–Golay filters for identification of nonstationary systems
    • Maciej Niedźwiecki
    • Marcin Ciołek
    2019 Full text AUTOMATICA

    The problem of identification of nonstationary systems using noncausal estimation schemes is consid-ered and a new class of identification algorithms, combining the basis functions approach with localestimationtechnique,isdescribed.Unliketheclassicalbasisfunctionestimationschemes,theproposedlocal basis function estimators are not used to obtain interval approximations of the parametertrajectory, but provide a sequence of point estimates corresponding to consecutive instants of time.Based on the results of theoretical analysis conducted for nonstationary finite impulse responsesystems the paper proposes two mechanisms for adaptive selection of the number of basis functionsand the size of the local analysis window.

  • Generating sequences of Lefschetz numbers of iterates
    • Grzegorz Graff
    • Małgorzata Lebiedź
    • Piotr Nowak-Przygodzki
    2019 Full text MONATSHEFTE FUR MATHEMATIK

    Du, Huang and Li showed in 2003 that the class of Dold–Fermat sequences coincides with the class of Newton sequences, which are defined in terms of socalled generating sequences. The sequences of Lefschetz numbers of iterates form an important subclass of Dold–Fermat (thus also Newton) sequences. In this paper we characterize generating sequences of Lefschetz numbers of iterates.

  • Generation and Propagation of Nonlinear Waves in a Towing Tank
    • Marcin Drzewiecki
    • Wojciech Sulisz
    2019 Full text Polish Maritime Research

    The paper presents the results of the research focused on linear and nonlinear wave generation and propagation in a deepwater towing tank equipped with a single flap-type wavemaker of variable draft. The problem of wave generation and propagation has been theoretically formulated and solved by applying an analytical method; linear and nonlinear solutions were obtained. The linear solution has been verified experimentally. The laboratory experiments confirmed that a linear model can be applied to predict the generation and propagation of water waves of low steepness. However, according to the analysis, the discrepancies between wave profiles predicted by applying the linear and nonlinear models rapidly increases with increasing wave steepness. Additionally, the secondary phenomena which occur in the towing tank, including: disintegration of wave profile, wave reflections from the beach and wave damping, were analyzed. Knowledge on the nonlinear processes and phenomena is essential for modeling the environmental conditions during tests carried out to secure the safety of the naval and offshore constructions. The theoretical formulation was derived and the solution was obtained by the Institute of Hydroengineering of the Polish Academy of Sciences IBW PAN while the experimental research was carried out in Ship Hydromechanics Division of the Ship Design and Research Centre CTO S.A.

  • Genotoxicity of selected pharmaceuticals, their binary mixtures, and varying environmental conditions – study with human adenocarcinoma cancer HT29 cell line
    • Monika Wieczerzak
    • Jacek Namieśnik
    • Błażej Kudłak
    2019 Full text DRUG AND CHEMICAL TOXICOLOGY

    Pharmaceutical residues are present in the environment in mixtures and their adverse effects may also result from interactions that occur between compounds. Studies presented in this work focus on genotoxicity of pharmaceuticals from different therapeutic groups in mixtures and in individual solutions impacted with different environmental conditions assessed using comet assay (alkaline approach). Binary mixtures of pharmaceuticals (in different concentration ratios) and in individual solutions impacted with pH change (range from 5.5 to 8.5) or addition of inorganic ions, were incubated with HT29 cells and after 24 h time period cells were tested for the presence of DNA damage. To estimate whether mixtures act more (synergistic) or less (antagonistic) efficiently Concentrations Addition (CA) and Independent Action (IA) approaches were applied followed by a calculation of the Model Deviation Ratio (MDR) to determine deviation from the predicted values. Addition of inorganic ions mainly reduced their genotoxicity. Diclofenac s. was the most susceptible to potassium, fluoride, and bromide ions. Change of the pH of pharmaceutical solutions had significant impact on genotoxicity of diclofenac s. and fluoxetine h. Among mixtures, more commonly observed interactions were synergistic ones, exactly twenty-five cases (ten pairs containing chloramphenicol or oxytetracycline h.) and ten cases of antagonism (four for pairs containing chloramphenicol or fluoxetine h.). The results obtained indicate that interactions between tested compounds occur frequently and can lead to DNA damage. This topic especially concerning in vitro tests using cells is still rare, however, it should not be neglected.

  • Geochemical fractionation of organic matter in the Jurassic-Cretaceous Vaca Muerta shale, Argentina
    • Aleksandra Małachowska
    2019

    Several studies have indicated the presence of more than one generation of bitumen that could be isolated from rocks through sequential extraction or after demineralization or both. Nabbefeld et al. (2010a) and Holman et al. (2012, 2014) termed bitumen obtained after solvent extraction from the undigested rock as “Bitumen I" and that obtained by extraction after demineralization of rock as “Bitumen II.” The occurrence of different bitumen fractions in rocks poses the question of whether subsequent bitumens are of the same origin as those of the first generation, remaining trapped in the rock matrix and unable to be easily extracted, or if they originated from different source. Based on the distinct composition of Bitumen I and Bitumen II in Paleoproterozoic marine rocks in Australia, Williford et al. (2011) and Holman et al. (2012, 2014) suggested that Bitumen II was closely related to the in-situ organic matter, whereas Bitumen I could be over- printed by migrated hydrocarbon phases. The investigation includes the chemical functional group characteristics and origin of different bitumen fractions present in Jurassic to early Cretaceous Vaca Muerta Formation from Argentina. The main objectives of the paper were to relate the differences in chemical functional groups of the two bitumen fractions to their origin in correspondence to kerogen macerals present in Jurassic to early Cretaceous Vaca Muerta Formation from Argentina. The impact of thermal decomposition of kerogen to Bitumen I and Bitumen II was discussed with regard to hydrocarbons mobilization in shales. The research is broadly described in Malachowska et al., 2019.

  • Geoscience Methods in Real Estate Market Analyses Subjectivity Decrease
    • Malgorzata Renigier-Biłozor
    • Artur Janowski
    • Marek Walacik
    2019 Full text Geosciences

    Real estate management, including real estate market analysis, is part of a so-called geosystem. In recent years, the popularity of creating various types of systems and automatic solutions in real estate management, including those related to property classification and valuation, has been growing in the world, mainly to reduce the impact of human subjectivity, to increase the scope of analyses and reduce research time. A very important fact that should be underlined is that properties are strongly related to geolocation (space) and strongly determine it. Authors proposed in the paper solutions that highlight implementation of geoscience and “geo-approach” combined with fuzzy logic methods that allow to decrease subjectivity in property analyses and diminish uncertainty in decision making process. The proposed methodology involves three main problematic components of decision support system in property investment analyses development with the use of geo-technologies such as: determination of the database model; elaboration geo-property-zones with geoprocessing activities; identification of homogeneous group of properties transactions. The influence of spatial decision factor determined in the study lead to objective and precise calculation of value differentiation from 22 to 43% depending on the property’s remoteness to the sea.

  • Geotechnical characterization of soft soil deposits in Northern Poland
    • Jakub Konkol
    • Kamila Międlarz
    • Lech Bałachowski
    2019 Full text ENGINEERING GEOLOGY

    This paper presents a geotechnical characterization of deltaic soft soil deposits in the Vistula Marshlands, northern Poland. It shows the limited applicability of organic soil classifications based on Cone Penetration Tests (CPTU) and Dilatometer Tests (DMT). None of the in-situ-based classifications correctly identifies peat. Analysis of the behaviour of contractive/dilative soil layers according to Robertson's updated classification (2016) is shown to be in agreement with volumetric changes observed during triaxial compression tests. The coefficient of primary compression Cc is found to decrease exponentially with the initial bulk density (ρd0) and to increase linearly with the in-situ water content (wc). The presented geotechnical characterization and reference data can be used for foundation design and soil improvement in the soft organic soils of northern Poland.

  • Global and regional economic inequality: Methods of measurement and evidences
    • Stanisław Kot
    • Katarzyna Ostasiewicz
    2019

    The lack of countries’ statistical income data, comparable across countries and years, seems to be the main reason of controversial conjectures concerning global inequality and its evolution over time. In the databases, which purport to collect income data on a worldwide scale, only some summary statistics (quantile income shares, means, Gini indices) are presented. Therefore, the development of efficient methods of extracting micro-data from available secondary statistics now seems to be the only way of overcoming the scarcity of national household surveys’ samples. In this monograph, a new method of retrieving the global sample of incomes is proposed. This method, based on the Sequential Probability Ratio Test, generates random samples, which reconstruct unavailable national samples with predetermined statistical reliability and numerical precision. The application of this method brings empirical evidences which contradict the widespread opinion about rising global inequality in two recent decades.

  • Global Approaches to Reduce Light Pollution from Media Architecture and Non-Static, Self-Luminous LED Displays for Mixed-Use Urban Developments
    • Karolina Zielińska-Dąbkowska
    • Kyra Xavia
    2019 Full text Sustainability

    Urban environments have become significantly brighter and more illuminated, and cities now consider media architecture and non-static, self-luminous LED displays an essential element of their strategy to attract residents, visitors, and tourists in the hours after dark. Unfortunately, most often, they are not designed with care, consideration, and awareness, nor do they support the visual wellbeing and circadian rhythms of humans. They also increase light pollution which has an adverse effect on the environment. The aim of this study was to estimate the scale of the negative impact of 28 non-static, self-luminous LED shop window displays within a real-life city context along the main shopping street Banhofstrasse in Zurich, Switzerland. An experimental field measurement survey investigation was performed to identify visual luminance with commonly available tools such as a luminance meter and a digital reflex camera for luminance photography. Moreover, the most important global approaches to reduce light pollution were evaluated in the form of existing guidelines, technical standards, and laws, all of which should be considered when specifying illuminated digital advertisements. A literature review and survey results both confirmed the extent of the problem and highlighted, too, the need to better measure, apply, and manage this new technology. The authors’ proposal for improvements involve practical recommendations for the design and implementation of future projects which can positively guide and direct this growing trend.

  • Global edge alliances in graphs
    • Robert Lewoń
    • Anna Małafiejska
    • Michał Małafiejski
    • Kacper Wereszko
    2019 Full text DISCRETE APPLIED MATHEMATICS

    In the paper we introduce and study a new problem of finding a minimum global edge alliance in a graph which is related to the global defensive alliance (Haynes et al., 2013; Hedetniemi, 2004) and the global defensive set (Lewoń et al., 2016). We proved the NP-completeness of the global edge alliance problem for subcubic graphs and we constructed polynomial time algorithms for trees. We found the exact values of the size of the minimum global edge alliance for certain classes: paths, cycles, wheels, complete k-partite graphs and complete k-ary trees. Moreover, we proved some lower bounds for arbitrary graphs.

  • Global Value Chains and Wages: Multi-Country Evidence from Linked Worker-Industry Data
    • Aleksandra Parteka
    • Joanna Wolszczak-Derlacz
    2019 Full text OPEN ECONOMIES REVIEW

    This paper uses a multi-country microeconomic setting to contribute to the literature on the nexus between production fragmentation and wages. Exploiting a rich dataset on over 110,000 workers from nine Eastern and Western European countries and the United States, we study the relationship between individual workers’ wages and industry ties into global value chains (GVCs). We find an inverse (but weak) relationship between the degree of industries’ involvement in GVCs and wages. Workers employed in routine occupations clearly earn less, but it is difficult to attribute it to the role played by the involvement of their countries and industries in global value chains.

  • Gość Inność, Wystawa sztuki współczesnej, Galeria MD_S, Wrocław 2019
    • Patryk Różycki
    2019

    Grudzień. Zimno, szaro, mokro, wszyscy biegają, żeby wyrobić się na święta; żeby kupić prezenty, odwiedzić rodzinę do której średnio chce Ci się jechać, żeby usiąść przy stole, odpowiadać na sztywne pytania w sztywnych koszulach, zapychając usta karpiem. Zapraszamy w gościnę do galerii MD_S 20 grudnia, gdzie o 18:00 będzie biła ciepłem i przytulnością, bo gościnność nie ocenia tak jak my nie oceniamy, każdy z nas jest gościem i każdy z nas jest inny. Każde ciało ma swój zapach, po co się kłócić o perfumy? Gościnność nie wybiera, stwarza przestrzeń do wspólnego obcowania. Klementyna Epa Malwina Gaj Wiktor Gałka Drag queen Larwa Kasper Lecnim Mortimer Hesper Patryk Różycki Michał Rutz Agnieszka Sejud Łukasz Stokłosa Daniel Weiss Melania Wróblewska

  • Graphs with equal domination and certified domination numbers
    • Magda Dettlaff
    • Magdalena Lemańska
    • Jerzy Topp
    • Mateusz Miotk
    • Radosław Ziemann
    • Paweł Żyliński
    2019 Full text Opuscula Mathematica

    A setDof vertices of a graphG= (VG,EG) is a dominating set ofGif every vertexinVG−Dis adjacent to at least one vertex inD. The domination number (upper dominationnumber, respectively) ofG, denoted byγ(G) (Γ(G), respectively), is the cardinality ofa smallest (largest minimal, respectively) dominating set ofG. A subsetD⊆VGis calleda certified dominating set ofGifDis a dominating set ofGand every vertex inDhas eitherzero or at least two neighbors inVG−D. The cardinality of a smallest (largest minimal,respectively) certified dominating set ofGis called the certified (upper certified, respectively)domination number ofGand is denoted byγcer(G) (Γcer(G), respectively). In this paperrelations between domination, upper domination, certified domination and upper certifieddomination numbers of a graph are studied