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Case Study of Old Steel Riveted Railway Truss Bridge: From Material Characterization to Structural Analysis
PublicationThe structural analysis of an old steel riveted railway truss bridge located over the Maruska River on the Działdowo – Olsztyn, Poland railway line is performed in this paper to check its behaviour under today’s railway loads. The mechanical properties of construction steel extracted from the old steel bridge are investigated by tensile tests, impact tests through the Charpy pendulum impact V-notch, and an optical emission spectrometer....
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Influence of low-temperature physical hardening on stiffness and tensile strength of asphalt concrete and stone mastic asphalt
PublicationThis paper presents laboratory testing of stiffness modulus and indirect tensile strength of three asphalt concrete (AC) and three stone mastic asphalt (SMA) mixes after isothermal storage at temperature of -20oC, at different time intervals up to 16 days. The tests under repeated dynamic loading showed physical hardening of all tested mixes which was manifested by an evident increase of their stiffness moduli after isothermal...
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A brief note on entire fracture surface topography parameters for 18Ni300 maraging steel produced by LB-PBF after LCF
PublicationThe concept of entire fracture surface investigation is helpful in explaining fatigue phenomena. In this paper, this method has been applied for 18Ni300 maraging steel using a 3D measurement system. Before post-mortem analysis, the specimens produced by laser beam powder bed fusion (LB-PBF) were tested under low-cycle fatigue (LCF) for eight strain amplitudes in the interval 0.3% to 1.0%. The attention was placed on the relationship...
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Normalized Partial Scattering Cross Section for Performance Evaluation of Low-Observability Scattering Structures
PublicationThe development of diffusion metasurfaces created new opportunities to elevate the stealthiness of combat aircraft. Despite the potential significance of metasurfaces, their rigorous design methodologies are still lacking, especially in the context of meticulous control over the scattering of electromagnetic (EM) waves through geometry parameter tuning. Another practical issue is insufficiency of the existing performance metrics,...
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Analytical calculations of scattering lengths for a class of long-range potentials of interest for atomic physics
PublicationWe derive two equivalent analytical expressions for an $l$th partial-wave scattering length $a_{l}$ for central potentials with long-range tails of the form % \begin{math} \displaystyle V(r)=-\frac{\hbar^{2}}{2m}\frac{Br^{n-4}}{(r^{n-2}+R^{n-2})^{2}} -\frac{\hbar^{2}}{2m}\frac{C}{r^{2}(r^{n-2}+R^{n-2})}, \end{math} % ($r\geqslant r_{s}$, $R>0$). % For $C=0$, this family of potentials reduces to the Lenz potentials discussed in...
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Surrogate modeling of impedance matching transformers by means of variable‐fidelity electromagnetic simulations and nested cokriging
PublicationAccurate performance evaluation of microwave components can be carried out using full‐wave electromagnetic (EM) simulation tools, routinely employed for circuit verification but also in the design process itself. Unfortunately, the computational cost of EM‐driven design may be high. This is especially pertinent to tasks entailing considerable number of simulations (eg, parametric optimization, statistical analysis). A possible...
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Review of methods for assessing traffic conditions on basic motorway and expressway sections
PublicationMotorways and expressways are the core of each country’s road system. Road planning, design and management requires tools to ensure that roads have the right geometry, traffic layout and equipment. These include methods for capacity estimation and assessing traffic conditions. Because the paper focusses on the basic segments of motorways and expressways (sections located between interchanges and outside of their influence), its...
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Variable-Fidelity Simulation Models and Sparse Gradient Updates for Cost-Efficient Optimization of Compact Antenna Input Characteristics
PublicationDesign of antennas for the Internet of Things (IoT) applications requires taking into account several performance figures, both electrical (e.g., impedance matching) and field (gain, radiation pattern), but also physical constraints, primarily concerning size limitation. Fulfillment of stringent specifications necessitates the development of topologically complex structures described by a large number of geometry parameters that...
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Experimental studies on the impact of changing the pipe material on the propagation of the pressure wave during water hammer
PublicationAim of the paper is to present the results studying the water hammer phenomenon in pipes made of different materials, and to show the impact of changing the type of material of the pipe on the velocity of the pressure wave during the transient flow in the pipes. In terms of research material and methods, pipes made of galvanized steel and high-density polyethylene were tested. Measurements were made using strain gauges with a high...
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Reduced-cost optimization-based miniaturization of microwave passives by multi-resolution EM simulations for internet of things and space-limited applications
PublicationStringent performance specifications along with constraints imposed on physical dimensions, make the design of contemporary microwave components a truly onerous task. In recent years, the latter demand has been growing in importance, with the innovative application areas such as Internet of Things coming into play. The need to employ full-wave electromagnetic (EM) simu-lations for response evaluation, reliable yet CPU heavy, only...
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Novel Versatile Topologies and Design Optimization of Wide-Bandstop Frequency Selective Surfaces for X-Band, Ku-Band and Millimeter-Wave Applications
PublicationNovel designs of frequency selective surface (FSS) are presented for wideband applications in X, Ku and mmWave (millimeter Wave) bands. Two identical metallic layers of FSS are imprinted on both sides of the RO4003 substrate. The geometry parameters are optimized to maximize the bandstop at the specified in-band maximum transmission level of –10 dB; satisfaction of the latter condition is enforced through appropriate formulation...
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Taking advantage of symmetries: Gathering of many asynchronous oblivious robots on a ring
PublicationOne of the recently considered models of robot-based computing makes use of identical, memoryless mobile units placed in nodes of an anonymous graph. The robots operate in Look-Compute-Move cycles; in one cycle, a robot takes a snapshot of the current configuration (Look), takes a decision whether to stay idle or to move to one of the nodes adjacent to its current position (Compute), and in the latter case makes an instantaneous...
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A DFT+U study of carbon nanotubes under influence of a gate voltage
PublicationA possibility of appearance of antiferromagnetic ordering in armchair carbon nanotubes and graphene is studied using density functional theory within a DFT+U approach. It is shown that the Coulomb repulsion between electrons in the -orbitals of graphene would need to reach a threshold value of ,...
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Radioactivity of drilling cuttings from shale resources of the Lower Paleozoic Baltic Basin, Poland
PublicationFractionated drilling wastes originating from shale gas exploration in the Baltic Basin in Pomerania were subjected to the measurements of mean activity concentrations of naturally occurring radioactive materials (NORMs).To better understand rock structure and texture, the X-ray diffraction analysis (XRD) and scanning electron microscopy(SEM) observation were used. To compare activity concentration of radionuclides in bulk wastes...
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Molecular Strategy for Survival at a Critical High Temperature in Eschierichia coli
PublicationThe molecular mechanism supporting survival at a critical high temperature (CHT) in Escherichia coli was investigated. Genome-wide screening with a single-gene knockout library provided a list of genes indispensable for growth at 47°C, called thermotolerant genes. Genes for which expression was affected by exposure to CHT were identified by DNA chip analysis. Unexpectedly, the former contents did not overlap with the latter except...
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Capillary Electrophoresis in determination of short - chain carboxylic acids in aqueous samples
PublicationAnalysis of pollution is extremely important especially in areas directly adjacent tothe residential district. Studies show that short- chain carboxylic acids are a group ofcompounds widespread around sewage treatment plants, landfills, livestock farms. The mostcommon techniques for determination of short - chain carboxylic acids are chromatographictechniques, especially gas chromatography, whose main limitation is that only volatilemonocarboxylic...
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Surrogate-assisted EM-driven miniaturization of wideband microwave couplers by means of co-simulation low-fidelity models
PublicationThis article proposes a methodology for rapid design optimization of miniaturized wideband couplers. More specifically, a class of circuits is considered, in which conventional transmission lines are replaced by their abbreviated counterparts referred to as slow-wave compact cells. Our focus is on explicit reduction of the structure size as well as on reducing the CPU cost of the design process. For the sake of computational feasibility,...
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Estimating the Impact of Inflow on the Chemistry of Two Different Caldera Type Lakes Located on the Bali Island (Indonesia)
PublicationThis paper is a preliminary attempt to assess the composition of pollutants in two different caldera lakes situated in the Indonesian Archipelago: Batur and Bratan. Both lakes are characterized by largely different physico-chemical regimes; Batur Lake is located in an area that is currently volcanically active, unlike Bratan Lake. The latter is much smaller and shallower than Batur Lake. The concentration of pollutants in the Indonesian...
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Dual Active Bridge (DAB) DC-DC converter for multilevel propulsion converters for electrical multiple units (EMU)
PublicationSemiconductor power devices made from silicon carbide (SiC) reached a level of technology enabling their widespread use in power converters. Two different approaches to implementation of modern traction converters in electric multiple units (EMU) have been presented in recent years: (i) 3.3-kV SiC MOSFET-based three-level PWM inverter with regenerative braking and (ii) 6.5-kV IGBT-based four-quadrant power electronic traction transformer...
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INFLUENCE OF MEASURING CONDITIONS ON TYRE/ROAD NOISE
PublicationA decisive factor for the development of tyres and road surfaces is the ability to conduct representative and reproducible measurements of selected characteristics related to the interaction of tyres and road surfaces. In terms of tyre/road noise measurements in Europe two methods described in ISO/FDIS 11819-2 and ECE Regulation No.117 are used. The latter is compulsory for assigning the tyre noise labels. The methodologies differ...
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The chemistry of river–lake systems in the context of permafrost occurrence (Mongolia, Valley of the Lakes). Part I. Analysis of ion and trace metal concentrations
PublicationThis study provides a description of water chemistry in river–lake systems located in central Mongolia, at the borderline of permafrost occurrence. The analysis involved water samples collected from two river–lake systems: Baydrag River–Böön Tsagaan Lake system, and Shargalyuut/Tuyn Rivers–Orog Lake system. In the water samples, ions and trace elements were detected and quantified. Additionally, the parameters of pH, electrical...
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Benchmarking Performance of a Hybrid Intel Xeon/Xeon Phi System for Parallel Computation of Similarity Measures Between Large Vectors
PublicationThe paper deals with parallelization of computing similarity measures between large vectors. Such computations are important components within many applications and consequently are of high importance. Rather than focusing on optimization of the algorithm itself, assuming specific measures, the paper assumes a general scheme for finding similarity measures for all pairs of vectors and investigates optimizations for scalability...
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Multi-fidelity robust aerodynamic design optimization under mixed uncertainty
PublicationThe objective of this paper is to present a robust optimization algorithm for computationally efficient airfoil design under mixed (inherent and epistemic) uncertainty using a multi-fidelity approach. This algorithm exploits stochastic expansions derived from the Non-Intrusive Polynomial Chaos (NIPC) technique to create surrogate models utilized in the optimization process. A combined NIPC expansion approach is used, where both...
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EVALUATION OF LIQUID-GAS FLOW IN PIPELINE USING GAMMA-RAY ABSORPTION TECHNIQUE AND ADVANCED SIGNAL PROCESSING
PublicationLiquid-gas flows in pipelines appear in many industrial processes, e.g. in the nuclear, mining, and oil industry. The gamma-absorption technique is one of the methods that can be successfully applied to study such flows. This paper presents the use of thegamma-absorption method to determine the water-air flow parameters in a horizontal pipeline. Three flow types were studied in this work: plug, transitional plug-bubble,...
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A High-Arctic flow-through lake system hydrochemical changes: Revvatnet, southwestern Svalbard (years 2010–2018)
PublicationLake ecosystems are strongly coupled to features of their surrounding landscapes such as geomorphology, lithology, vegetation and hydrological characteristics. In the 2010–2018 summer seasons, we investigated an Arctic flow-through lake system Revvatnet, located in the vicinity of the coastal zone of Hornsund fjord in Svalbard, characterising its hydrological properties and the chemical composition of its waters. The lake system...
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Modelling Long‐Term Transition from Coal‐Reliant to Low‐Emission Power Grid and District Heating Systems in Poland
PublicationEnergy systems require technological changes towards climate neutrality. In Poland, where the power system is dominated by outdated coal-fired power plants, efforts to minimize the environmental impact are associated with high costs. Therefore, optimal paths for the development of the energy sector should be sought in order to achieve ambitious long-term strategic goals, while minimizing the negative impact on the consumers’ home...
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A novel architecture of Web-GIS for mapping and analysis of echinococcosis in Poland
PublicationEchinococcosis is an infectious disease transferred through ingestion of food or water which have been contaminated with eggs of the Echinococcus tapeworm, which are spread by intermediate parasite hosts. Because the latter are primarily territorial, research related to diagnosis and prevention of echinococcosis requires investigation of environmental factors, which can be supported with the use of a Geographical Information System...
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A Cost-Effective Method for Reconstructing City-Building 3D Models from Sparse Lidar Point Clouds
PublicationThe recent popularization of airborne lidar scanners has provided a steady source of point cloud datasets containing the altitudes of bare earth surface and vegetation features as well as man-made structures. In contrast to terrestrial lidar, which produces dense point clouds of small areas, airborne laser sensors usually deliver sparse datasets that cover large municipalities. The latter are very useful in constructing digital...
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Rapid Variable-Resolution Parameter Tuning of Antenna Structures Using Frequency-Based Regularization and Sparse Sensitivity Updates
PublicationGeometry parameter tuning is an inherent part of antenna design process. While most often performed in a local sense, it still entails considerable computational expenses when carried out at the level of full-wave electromagnetic (EM) simulation models. Moreover, the optimization outcome may be impaired if good initial design is not available. This paper proposes a novel approach to fast and improved-reliability gradient-based...
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Expedited Variable-Resolution Surrogate Modeling of Miniaturized Microwave Passives in Confined Domains
PublicationDesign of miniaturized microwave components is largely based on computational models, primarily, full-wave electromagnetic (EM) simulations. EM analysis is capable of giving an accurate account for cross-coupling effects, substrate and radiation losses, or interactions with environmental components (e.g., connectors). Unfortunately, direct execution of EM-based design tasks such as parametric optimization or uncertainty quantification,...
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Mapping the Transglycosylation Relevant Sites of Cold-Adapted β-D-Galactosidase from Arthrobacter sp. 32cB
PublicationB-Galactosidase from Arthrobacter sp. 32cB (ArthbetaDG) is a cold-adapted enzyme able to catalyze hydrolysis of beta-D-galactosides and transglycosylation reaction, where galactosyl moiety is being transferred onto an acceptor larger than a water molecule. Mutants of ArthbetaDG D207A and E517Q were designed to determine the significance of specific residues and to enable formation of complexes with lactulose and sucrose and to...
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Nickel-based catalysts for electrolytic decomposition of ammonia towards hydrogen production
PublicationNickel is an attractive metal for electrochemical applications because it is abundant, cheap, chemically resilient, and catalytically active towards many reactions. Nickel-based materials (metallic nickel, its alloys, oxides, hydroxides, and composites) have been also considered as promising electrocatalysts for ammonia oxidation. The electrolysis of ammonia aqueous solution results in evolution of gaseous hydrogen and nitrogen....
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Leakage Current Measurements of Surge Arresters
PublicationThe paper presents the methods of assessing the technical condition of varistor surge arresters used in laboratory tests and in operation—performed without disconnecting the arresters from the network. The analysis of the diagnostic methods was supplemented with the results of the measurements of the leakage current of arresters coming directly from their production and used in the power industry. Among the available methods of...
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Graph Neural Networks and Structural Information on Ionic Liquids: A Cheminformatics Study on Molecular Physicochemical Property Prediction
PublicationIonic liquids (ILs) provide a promising solution in many industrial applications, such as solvents, absorbents, electrolytes, catalysts, lubricants, and many others. However, due to the enormous variety of their structures, uncovering or designing those with optimal attributes requires expensive and exhaustive simulations and experiments. For these reasons, searching for an efficient theoretical tool for finding the relationship...
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X-ray diffraction patterns of BaCe0.6Zr0.2Y0.1M0.1O3-δ (M = Fe, Pr, Tb)
Open Research DataThe dataset consists of three raw X-ray diffraction (XRD) files collected using a Phillips X’Pert Pro diffractometer (CuKα radiation (𝜆 = 1.541 Å), under 40 kV and 30 mA). The diffraction patterns of BaCe0.6Zr0.2Y0.1Fe0.1O3-δ (BCZYFe), BaCe0.6Zr0.2Y0.1Pr0.1O3-δ (BCZYPr), and BaCe0.6Zr0.2Y0.1Tb0.1O3-δ (BCZYTb) were collected at room temperature. Collected...
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Construction, production and evaluation of the diagnostic utility of a recombinant Toxoplasma gondii chimeric antigen SAG1-SAG2-MAG1S
Open Research DataThe intracellular parasite Toxoplasma gondii has the ability to infect a wide range of warm-blooded animals, including humans. Currently, diagnosis of toxoplasmosis is based mainly on the use of the native antigens in enzyme immunoassay which allow for detection of IgG, IgM and IgA antibody classes. However, in some cases the performed studies give...
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Construction, production and evaluation of the diagnostic utility of a recombinant Toxoplasma gondii chimeric antigen AMA1-MIC1-MIC3
Open Research DataThe intracellular parasite Toxoplasma gondii has the ability to infect a wide range of warm-blooded animals, including humans. Currently, diagnosis of toxoplasmosis is based mainly on the use of the native antigens in enzyme immunoassay which allow for detection of IgG, IgM and IgA antibody classes. However, in some cases the performed studies give...
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Construction, production and evaluation of the diagnostic utility of a recombinant Toxoplasma gondii chimeric antigen MIC3-MAG1-ROP1
Open Research DataThe intracellular parasite Toxoplasma gondii has the ability to infect a wide range of warm-blooded animals, including humans. Currently, diagnosis of toxoplasmosis is based mainly on the use of the native antigens in enzyme immunoassay which allow for detection of IgG, IgM and IgA antibody classes. However, in some cases the performed studies give...
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Construction, production and evaluation of the diagnostic utility of a recombinant Toxoplasma gondii chimeric antigen MIC1-MIC3-ROP1
Open Research DataThe intracellular parasite Toxoplasma gondii has the ability to infect a wide range of warm-blooded animals, including humans. Currently, diagnosis of toxoplasmosis is based mainly on the use of the native antigens in enzyme immunoassay which allow for detection of IgG, IgM and IgA antibody classes. However, in some cases the performed studies give...
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Construction, production and evaluation of the diagnostic utility of a recombinant Toxoplasma gondii chimeric antigen MIC3-MAG1-AMA1
Open Research DataThe intracellular parasite Toxoplasma gondii has the ability to infect a wide range of warm-blooded animals, including humans. Currently, diagnosis of toxoplasmosis is based mainly on the use of the native antigens in enzyme immunoassay which allow for detection of IgG, IgM and IgA antibody classes. However, in some cases the performed studies give...
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Construction, production and evaluation of the diagnostic utility of a recombinant Toxoplasma gondii chimeric antigen AMA1-MIC1-ROP1
Open Research DataThe intracellular parasite Toxoplasma gondii has the ability to infect a wide range of warm-blooded animals, including humans. Currently, diagnosis of toxoplasmosis is based mainly on the use of the native antigens in enzyme immunoassay which allow for detection of IgG, IgM and IgA antibody classes. However, in some cases the performed studies give...
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Construction, production and evaluation of the diagnostic utility of a recombinant Toxoplasma gondii chimeric antigen SAG1-SAG2-MIC1S
Open Research DataThe intracellular parasite Toxoplasma gondii has the ability to infect a wide range of warm-blooded animals, including humans. Currently, diagnosis of toxoplasmosis is based mainly on the use of the native antigens in enzyme immunoassay which allow for detection of IgG, IgM and IgA antibody classes. However, in some cases the performed studies give...
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Energy Security of Polish Consumers in 2004-2021
Open Research DataEnergy security is one of the most important components of economic security. It is influenced not only by access to energy sources and the economic situation of the state and the individual consumer. In the years 2004–2021, energy security of the individual consumer in the economic dimension significantly improved. This was due to several factors:1....
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Seasonal changes of mercury speciation in the coastal sediments
PublicationPurpose Mercury speciation in sediments is linked to environmental conditions and processes. Domination of particular mercury species depends on its source, displays considerable seasonal behavior, and may be further modified due to oxygen levels, icing conditions, or the input of fresh organic matter. The purpose of this study was to examine the coastal area of the Gulf of Gdańsk in terms of mercury contamination and the influence...
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Ranking of ecotoxisity tests for underground water assessment using the Hasse diagram technique
PublicationThe present study deals with the novel application of the Hasse diagram technique (HDT) for the specific ranking of ecotoxicity tests capable of assessment of underground water quality. The area studied is a multi-municipal landfill in the northern Poland. The monitoring network of the landfill constitutes of 27 piezometers for underground water monitoring and two observation points at surface water courses. After sampling, chemical...
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Converting beach wrack into a resource as a challenge for the Baltic Sea (an overview)
PublicationThe paper distinguishes beach wrack, the marine generated organic part of beach cast, as a separate management object and discusses research questions related to its management and economically viable use. Based on experiences from the Baltic Sea and existing practices from countries with different management systems clear distinction between the management of natural and anthropogenic components of cast material is seen as an...
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V DZIEŃ STREFY na Politechnice Gdańskiej
EventsBiuro Karier wraz z PSSE serdecznie zapraszają na V DZIEŃ STREFY podczas którego studenci i absolwenci będą mieli możliwość poznania firm działających w PSSE oraz skonfrontowania swoich wyobrażeń o pracy w danej branży.
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[ZiJ, EiF] Qualitative research methods 2020-21
e-Learning Courses{mlang pl} Dyscyplina: nauki o zarządzaniu i jakości; ekonomia i finanse Zajęcia obowiązkowe dla doktorantów I roku Prowadzący: dr hab. inż. Krzysztof Zięba, prof. PG Liczba godzin: 30 Forma zajęć: laboratoria {mlang} {mlang en} Discipline: management and quality; economics and finance Obligatory course for 1st-year PhD students Academic teacher: dr hab. inż. Krzysztof Zięba, prof. PG Total hours of training: 30 teaching...
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Rozwój zrównoważony w planowaniu strategicznym w miastach powiatowych na obszarze peryferyjnym woj. pomorskiego
PublicationCelem pracy było rozpoznanie, czy i w jakim zakresie zasady rozwoju zrównoważonego są obecne w planowaniu strategicznym w miastach powiatowych na obszarach peryferyjnych województwa pomorskiego. Wybrano taki zestaw miast, ponieważ ich rozwój może odegrać istotną rolę w aktywizacji obszarów peryferyjnych (miasta w obszarach metropolitalnych mają odrębną specyfikę). Cechy rozwoju zrównoważonego opisane w teorii oraz dokumentach krajowych...
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Analiza holenderskich doświadczeń w zakresie logistyki miejskiej
PublicationW artykule dokonano analizy holenderskich doświadczeń w zakresie logistyki miejskiej i organizacji systemu dostaw towarów na przykładzie Utrechtu. Wybór miasta podyktowany był ponad 20 letnim konsekwentnym zaangażowaniem i doświadczeniem w tej dziedzinie. Przedstawiono zmiany w podejściu do problemów miejskiego transportu ładunków z punktu widzenia polityki krajowej oraz przebieg procesu decentralizacji odpowiedzialności na poziom...