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Publications from the year 2022
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Portico Farmhouses of the Vistula Delta: Architecture, Current State and Finite Element Modelling of Timber Roof Truss under Material and Cross-section Uncertainty
- Tomasz Zybała
- Katarzyna Szepietowska
- Grzegorz Bukal
- Izabela Lubowiecka
The article focuses on the oldest surviving I-type portico houses located in the Vistula Delta, which were built in the 17th and 18th centuries. The study describes the houses’ origins, structure, details of roof structures and technical condition, and it also includes numerical modelling of a roof truss and its mechanical analysis. Numerical models of the roof trusses are defined and analysed by means of the finite element method. Global sensitivity analysis with the use of the polynomial chaos expansion method is used to study the influence of uncertainties in material properties of wood, such as Young’s modulus and the friction coefficient, and also the beam cross-sectional height in the output of the numerical model of the structure. The outcomes show that the uncertainty of beam height exerts the dominating influence on the maximum deflection of the roof truss, hence accurate measurements of geometry are of great importance in the planning of conservation and renovation of such historic structures.
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Position Estimation in Mixed Indoor-Outdoor Environment Using Signals of Opportunity and Deep Learning Approach
- Sebastian Urwan
- Dominika Wysocka
- Alicja Pietrzak
- Krzysztof Cwalina
To improve the user's localization estimation in indoor and outdoor environment a novel radiolocalization system using deep learning dedicated to work both in indoor and outdoor environment is proposed. It is based on the radio signatures using radio signals of opportunity from LTE an WiFi networks. The measurements of channel state estimators from LTE network and from WiFi network are taken by using the developed application. The user's position is calculated with a trained neural network system's models. Additionally the influence of various number of measurements from LTE and WiFi networks in the input vector on the positioning accuracy was examined. From the results it can be seen that using hybrid deep learning algorithm with a radio signatures method can result in localization error 24.3 m and 1.9 m lower comparing respectively to the GPS system and standalone deep learning algorithm with a radio signatures method in indoor environment. What is more, the combination of LTE and WiFi signals measurement in an input vector results in better indoor and outdoor as well as floor classification accuracy and less positioning error comparing to the input vector consisting measurements from only LTE network or from only WiFi network.
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Position in global value chains and wages in Central and Eastern European countries
- Sabina Szymczak
- Aleksandra Parteka
- Joanna Wolszczak-Derlacz
This paper examines the relationship between the relative position of industries in Global Value Chains (GVC) and wages in 10 Central and Eastern European countries. We combine GVC measures of global import intensity of production, upstreamness and the length of the value chain with micro-data on workers. We find that the wages of Central and Eastern European countries workers are higher when their industry is at the beginning of the chain or at the end than in the middle. Secondly, wage changes depend on the interplay between upstreamness and GVC intensity. In sectors close to final demand, greater production fragmentation is associated with lower wages.
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Possible quadrupole-order-driven commensurate-incommensurate phase transition in B20 CoGe
- S.-H. Baek
- Vladimir Sidorov
- A. V. Nikolaev
- Tomasz Klimczuk
- Filip Ronning
- A. V. Tsvyashchenko
The B20-type cobalt germanide CoGe was investigated by measuring the specific heat, resistivity, and 59Co nuclear magnetic resonance (NMR).We observed a phase transition at TQ = 13.7 K, evidenced by a very narrow peak of the specific heat and sharp changes of the nuclear spin-spin (T −1 2 ) and spin-lattice (T −1 1 ) relaxation rates. The fact that the entropy release is extremely small and the Knight shift is almost independent of temperature down to low temperatures as anticipated in a paramagnetic metal indicates that the TQ transition is of nonmagnetic origin. In addition, we detected a crossover scale T0 ∼ 30 K below which the resistivity and the NMR linewidth increase, and T −1 1 is progressively distributed in space, that is, a static and dynamical spatial inhomogeneity develops. While the order parameter for the TQ transition remains an open question, a group-theoretical analysis suggests that the finite electric quadrupole density arising from the low local site symmetry at cobalt sites could drive the crystal symmetry lowering from the P213 symmetry that is commensurate to the R3 symmetry with an incommensurate wave vector, which fairly well accounts for the TQ transition. The quadrupole-order-driven commensurate-incommensurate phase transition may be another remarkable phenomenon arising from the structural chirality inherent in the noncentrosymmetric B20 family.
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Potential Energy Curves of Diatomic Alkali Molecules Datasets
- Patryk Jasik
- Tymon Kilich
The datasets described in this article contain potential energy curves for several diatomic systems. The data was obtained via high-performance computing using MOLPRO, a system of ab initio programs for advanced molecular electronic structure calculations. The datasets allow to model bond lengths, energy levels, spectra and time-evolution of molecular dimers for which the data are presented.
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Potential of Functionalized Polyolefins in a Sustainable Polymer Economy: Synthetic Strategies and Applications
- Lidia Jasińska-Walc
- Rob Duchateau
- Miloud Bouyahyi
Polymers play a crucial role in our modern life as no other material exists that is so versatile, moldable, and lightweight. Consequently, the demand for polymers will continue to grow with the human population, modernization, and technological developments. However, depleted fossil resources, increasing plastic waste production, ocean pollution, and related growing emission of greenhouse gases has led to a change in the way we think about the use of polymers. Although polymers were never designed to be recycled, it is clear that a linear polymers economy is no longer sustainable. The design for recycling and reuse and life-cycle analyses will become increasingly important factors when deciding on which polymer to choose for a certain application. Of all polymers, polyolefins have the lowest life-cycle environmental impact and even outperform renewable polymers. However, polyolefins are chemically inert and reveal a low surface energy. Combining their excellent mechanical properties with the ability to adhere to other materials or create self-assembled or nanostructured materials would widen the application window of polyolefins even more.
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Potential of nanocomposites of zero valent copper and magnetite with Eleocharis dulcis biochar for packed column and batch scale removal of Congo red dye
- Muhammad Imran
- A Natasha
- Behzad Murtaza
- Sabah Ansar
- Noor S. Shah
- Zia Ul Haq Khan
- Ali Shahid
- Grzegorz Boczkaj
- Farhan Hafeez
- Ali Shafaqat
- Muhammad Rizwan
The current study is the first attempt to prepare nanocomposites of Eleocharis dulcis biochar (EDB) with nano zero-valent Copper (nZVCu/EDB) and magnetite nanoparticles (MNPs/EDB) for batch and column scale sequestration of Congo Red dye (CR) from synthetic and natural water. The adsorbents were characterized with advanced analytical techniques. The impact of EDB, MNPs/EDB and nZVCu/EDB dosage (1–4 g/L), pH (4–10), initial concentration of CR (20–500 mg/L), interaction time (180 min) and material type to remove CR from water was examined at ambient temperature. The CR removal followed sequence of nZVCu/EDB > MNPs/EDB > EDB (84.9–98% > 77–95% > 69.5–93%) at dosage 2 g/L when CR concentration was increased from 20 to 500 mg/L. The MNPs/EDB and nZVCu/EDB showed 10.9% and 20.1% higher CR removal than EDB. The adsorption capacity of nZVCu/EDB, MNPs/EDB and EDB was 212, 193 and 174 mg/g, respectively. Freundlich model proved more suitable for sorption experiments while pseudo 2nd order kinetic model well explained the adsorption kinetics. Fixed bed column scale results revealed excellent retention of CR (99%) even at 500 mg/L till 2 h when packed column was filled with 3.0 g nZVCu/EDB, MNPs/EDB and EDB. These results revealed that nanocomposites with biochar can be applied efficiently for the decontamination of CR contaminated water.
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Potentiometric sensor containing set of ion selective electrodes with lipid modified membranes for quality assessment of tested non-alcoholic beverages
- Maria Szpakowska
- Jakub Szwacki
- Ewa Marjańska
Potentiometric sensors may be a good tool for fast quality control of commercial drinks. In this work, such a sensor, containing a set of ion-selective electrodes with lipid-modified membranes (benzylhexadecyldimethylammonium chloride monohydrate, hexadecylamine, 1-dodecanol, elaidic acid, cholesterol) was used for discrimination and quality control of non-alcoholic beverages, mainly composed of sugar and citric acid. It was found that the electrodes stability, membrane reproducibility and sensitivity to acetic, hydrochloric and citric acid concentration were very good. On the contrary, ion selective electrodes were not sensitive to sweet substances (glucose, fructose, sucrose) concentration changes. The potentiometric sensor consisting of ion-selective electrodes was applied to commercially available non-alcoholic beverages, a reference drink and to di-component mixtures of sucrose and citric acid. A database of its responses to those mixtures was created. The possibility of using a “fingerprint” method for recognition and quality control of unknown beverages was discussed. The sensor responses to non-alcoholic beverages were transformed by principal component analysis and agglomerative hierarchical clustering analysis and compared to the results obtained with sensory analysis. The tested drinks can be divided into two groups of similar sour taste intensity (lemonades and orangeades). The beverage of low sour taste intensity and the non-carbonated drink were outside these groups. The obtained results show that the potentiometric sensor with lipid-modified ion-selective electrodes may be a useful tool for quality control of unknown drinks on the last step of a production line.
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Potyczki algorytmiczne, czyli Alicja i Bogdan w nowych sytuacjach. Alicja i Bogdan w naleśnikarni
- Marek Kubale
Niniejszym esejem inaugurujemy , po kilkuletniej przerwie, nową serię zagadek algorytmicznych.Pierwszy odcinek nosi nazwę Alicja i Bogdan w naleśnikarni.
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Pounding between high-rise buildings with different structural arrangements
- Mahmoud Miari
- Robert Jankowski
Earthquake-induced structural pounding has led to significant damages during previous earthquakes. This paper investigates the effect of pounding on the dynamic response of colliding high-rise buildings with different structural arrangements. Three 3-D buildings are considered in the study, including 5-storey building, 7-storey building and 9-storey building. Three pounding scenarios are also taken into account, i.e. pounding between 5-storey and 7-storey buildings, pounding between 5-storey and 9-storey buildings and pounding between 7-storey and 9-storey buildings. These three pounding scenarios are studied and compared with the no pounding case. The results show that the level of accelerations of colliding buildings significantly increases for all scenarios, as compared to the no pounding case. At the same time, displacements experience both increase and decrease, while the peak storey shears experience an increase due to pounding with few exceptions regarding the top storeys. Finally, pounding leads to the generation of dangerous impact forces with higher peak values experienced in taller buildings.
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Power Converter Solutions for Industrial PV Applications—A Review
- Ievgen Verbytskyi
- Mykola Lukianov
- Kawsar Nassereddine
- Bohdan Pakhaliuk
- Oleksandr Husev
- Ryszard Strzelecki
: As the use of photovoltaics becomes more widespread, new technologies for more efficient energy generation, transmission, and distribution based on power electronics converters are being developed. The most common applications are grid-on, energy storage, hybrid, and high voltage gain applications. These applications impose several additional requirements in the design of power converters associated with the solar battery’s maximum power tracking and operation in a wide range of input currents and voltages. The practical realization of such solutions can be implemented on the basis of various topologies, which requires a preliminary application of criteria for assessing their effectiveness. The paper conducts a comparison of different topologies on power converters based on two parameters that describe their cost and power loss for various PV applications. For a straightforward study, these parameters are represented using the gain factor, which allows for an accurate comparison of the efficiency of various types of converters.
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Power efficient thrust allocation algorithms in design of dynamically positioned ships
- Agnieszka Piekło
- Anna Witkowska
- Tomasz Zubowicz
Assessment of power consumption on a Dynamically Positioned (DP) ship in the early design stage can assist crucial design choices. The study presents a comparison between two algorithms of optimal thrust allocation in a propulsion system for an over-actuated DP ship. Applied algorithms were Quadratic Programming (QP) and Non- dominated Sorting Genetic Algorithm II (NSGAII). Based on both approaches, tools were developed for ship design purposes. Based on a case study, QP optimization is more suited for universal use and fast analysis of many designs. With adequate optimization of NSGAII parameters, this algorithm can be effective for DP simulations at specified weather conditions. This is due to the possibility of application of original functions describing the DP problem, which is not possible in the case of QP optimization, where the problem needs to be simplified
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Power Hardware-In-the-Loop Approach for Autonomous Power Generation System Analysis
- Szymon Racewicz
- Filip Kutt
- Łukasz Sienkiewicz
The article presents the Power Hardware-In-the-Loop (PHIL) dynamic model of a synchronous generator of 125 kVA for autonomous power generation system analysis. This type of system is typically composed of electrical energy sources in the form of several diesel generator units with synchronous machines, the main distribution switchboard and different loads. In modern power distribution systems, the proposed power management strategies are typically aimed at the minimization of fuel consumption by maintaining the operation of diesel generator units at peak efficiency. In order to design and test such a system in conditions as close as possible to the real operating conditions, without constructing an actual power distribution system, a PHIL model in the form of a power inverter that emulates the behaviour of a real synchronous generator is proposed. The PHIL model was prepared in the MATLAB/Simulink environment, compiled to the C language and fed into a 150 kVA bidirectional DC/AC commercial-grade converter driven by a HIL real-time simulation control unit. Experimental research was performed in the LINTE2 laboratory of the Gdańsk University of Technology (Poland), where the PHIL emulator was developed. The proposed model was validated by comparing the output voltages and currents as well as an excitation current with the measurements performed on the 125 kVA synchronous generator. The obtained results proved satisfactory compliance of the PHIL model with its real counterpart.
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Powłoki malarskie w ochronie przeciwkorozyjnej. Zasady stosowania i kontrola jakości
- Andrzej Miszczyk
- Michał Szociński
- Kazimierz Darowicki
W książce przedstawiono podstawowe zasady wykonywania i kontroli jakości przeciwkorozyjnych wymalowań malarskich na konstrukcjach stalowych. Opracowanie powstało na bazie wykładów i zajęć praktycznych dla studentów Wydziału Chemicznego Politechniki Gdańskiej prowadzonych przez Katedrę Elektrochemii, Korozji i Inżynierii Materiałowej oraz realizowanych w ramach prac Katedry od około 12 lat kursów dla inspektorów powłok malarskich. Dotyczą one nadzoru wykonywania zabezpieczeń powłokowych na statkach morskich, w szczególności w zbiornikach balastowych. Kursy te są certyfikowane przez firmę DNV z siedzibą w Høvik w Norwegii, będącą znanym, międzynarodowym, akredytowanym towarzystwem klasyfikacyjnym. Prezentowane zasady omówiono na przykładzie konstrukcji morskich, jednak obowiązują one w przypadku każdej konstrukcji stalowej. Przedstawione w książce wymagania stawiane wykonawcom prezentują – zgodnie z obecnym stanem wiedzy i doświadczeń – optymalny poziom pod względem trwałości zabezpieczenia przeciwkorozyjnego. Książka została zaopatrzona w spis norm oraz słowniki terminów specjalistycznych: angielsko-niemiecko-polski i polsko-angielsko-niemiecki.
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Powojenny rozdział w historii architektury i zagospodarowania portu gdyńskiego
- Anna Orchowska-Smolińska
The port of Gdynia, considered one of the largest civil construction projects of the 20th century in Europe, was built at an express pace for only a dozen or so years from the mid-1920s to the end of the 1930s. Unusual solutions from the construction period in the port engineering category, as well as outstanding architectural works The industrial area quickly became architectural symbols of economic growth and the general rebirth of Poland after 1918. In April 1945, the Poles took over the property of the port after the war found a picture of the ruins and destruction of the port, mainly the result of deliberate plantings carried out on the orders of Adolf Hitler in the last 10 days before the capitulation of the Germans. The devastation of individual elements of the port infrastructure and buildings was assessed at the level from 25% to 100%. Post-war reconstruction of the port from damage, in the years 1945-1947 not only the losses were inventoried, but also significant decisions were made as to whether the building was to be rebuilt or a new investment was planned in its place. Studies on this subject show that the investment reconstruction of the port did not continue the boldly outlined pre-war development plans, but from the point of view of its architecture, a new page in its history definitely opened up for this industrial complex.
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Prace doktorskie, habilitacje oraz profesury o tematyce chemii analitycznej i pokrewnej w 2021 r.
- Marek Biziuk
- Żaneta Polkowska
Publikacja zawiera zestawienie prac doktorskich, habilitacji oraz profesur o tematyce chemii analitycznej i pokrewnej w 2021 r.,
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Praseodymium Orthoniobate and Praseodymium Substituted Lanthanum Orthoniobate: Electrical and Structural Properties
- Kacper Dzierzgowski
- Sebastian Wachowski
- Marcin Łapiński
- Aleksandra Mielewczyk-Gryń
- Maria Gazda
In this paper, the structural properties and the electrical conductivity of La1−xPrxNbO4+δ (x = 0.00, 0.05, 0.1, 0.15, 0.2, 0.3) and PrNbO4+δ are presented and discussed. All synthesized samples crystallized in a monoclinic structure with similar thermal expansion coefficients. The phase transition temperature between the monoclinic and tetragonal structure increases with increasing praseodymium content from 500 ◦C for undoped LaNbO4+δ to 700 ◦C for PrNbO4+δ. Thermogravimetry, along with X-ray photoelectron spectroscopy, confirmed a mixed 3+/4+ oxidation state of praseodymium. All studied materials, in humid air, exhibited mixed protonic, oxygen ionic and hole conductivity. The highest total conductivity was measured in dry air at 700 ◦C for PrNbO4+δ, and its value was 1.4 · 10−3 S/cm.
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Precipitation of calcium carbonate in the presence of rhamnolipids in alginate hydrogels as a model of biomineralization
- Natalia Czaplicka
- Donata Konopacka-Łyskawa
- Agata Nowotnik
- Aleksandra Mielewczyk-Gryń
- Marcin Łapiński
- Rafał Bray
This paper reports the effects of rhamnolipids presence in the alginate hydrogel and CO32- solution, on the precipitation of CaCO3 in the Ca2+ loaded alginate hydrogel. Characteristics of the formed particles are discussed. Model conditions containing alginate hydrogel and rhamnolipids were used in order to mimic the natural environment of biomineralization in biofilms. It has been shown that rhamnolipids affect the characteristics of precipitated calcium carbonate effect of using these biosurfactants depends on their concentration as well as whether they are directly present in the hydrogel matrix or the carbonate solution surrounding the hydrogel. The greatest effect compared to the control samples was found for the rhamnolipids in the form of micelles directly present in the hydrogel with the CaCl2 cross-linked solution at concentration of 0.05 M. These conditions result in the highest increase in vaterite content, specific surface area, and pore volume. The mechanism of CaCO3 precipitation in alginate hydrogel containing rhamnolipids has been proposed.
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Precypitacja węglanu wapnia metodą karbonatyzacji z dodatkiem glicerolu w obecności wybranych promotorów absorpcji CO2
- Natalia Czaplicka
- Donata Konopacka-Łyskawa
- Barbara Kościelska
- Marcin Łapiński
Jednym ze sposobów produkcji węglanu wapnia jest metoda gaz-ciecz, w której jako reagent stosuje się gazowy CO2 oraz roztwór soli wapnia, do którego dodawane są związki sprzyjające absorpcji CO2, tzw. promotory. Reakcja z gazowym CO2 jest specyficzna, ponieważ powstawanie jonów wodorowęglanowych podczas absorpcji CO2 z reakcją chemiczną jest etapem decydującym o szybkości procesu strącania CaCO3. Celem niniejszej pracy było określenie wpływu glicerolu na przebieg wytrącania CaCO3 oraz charakterystykę wytworzonych cząstek metodą karbonatyzacji. Proces prowadzono w temperaturze pokojowej pod ciśnieniem atmosferycznym w reaktorze typu gas(CO2)-lift z cyrkulacją wewnętrzną. Mieszaninę reakcyjną stanowił roztwór CaCl2 zawierający 0, 5 lub 10% (obj.) glicerolu oraz promotor absorpcji CO2 w postaci amoniaku lub trietanoloaminy (TEA). Otrzymaną zawiesinę cząstek CaCO3 podzielono na dwie części. Pierwszą porcję przesączono natychmiast po zakończeniu reakcji, natomiast drugą rozdzielono po 1 godzinie. W celu scharakteryzowania otrzymanych cząstek określono ich skład polimorficzny, powierzchnię właściwą oraz morfologię. Największą powierzchnię właściwą miały próbki otrzymane w roztworach zawierających NH3, co jest skorelowane z zawartością waterytu. Dodatek glicerolu do mieszaniny reakcyjnej wpływa na szybkość absorpcji CO2 do układu oraz na szybkość dyfuzji jonów w mieszaninie reakcyjnej. Zatem im wyższe stężenie glicerolu tym dłuższy czas reakcji strącania. Ponadto dla zastosowanych stężeń glicerolu nie obserwowano stabilizacji metastabilnego waterytu.
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Predicting Ice Phenomena in a River Using the Artificial Neural Network and Extreme Gradient Boosting
- Renata Graf
- Tomasz Kolerski
- Senlin Zhu
Forecasting ice phenomena in river systems is of great importance because these phenomena are a fundamental part of the hydrological regime. Due to the stochasticity of ice phenomena, their prediction is a difficult process, especially when data sets are sparse or incomplete. In this study, two machine learning models—Multilayer Perceptron Neural Network (MLPNN) and Extreme Gradient Boosting (XGBoost)—were developed to predict ice phenomena in the Warta River in Poland in a temperate climate zone. Observational data from eight river gauges during the period 1983–2013 were used. The performance of the model was evaluated using four model fit measures. The results showed that the choice of input variables influenced the accuracy of the developed models. The most important predictors were the nature of phenomena on the day before an observation, as well as water and air temperatures; river flow and water level were less important for predicting the formation of ice phenomena. The modeling results showed that both MLPNN and XGBoost provided promising results for the prediction of ice phenomena. The research results of the present study could also be useful for predicting ice phenomena in other regions.