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Search results for: marginal ice zone
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Fast Design Optimization of Waveguide Filters Applying Shape Deformation Techniques
PublicationThis paper presents an efficient design of microwave filters by means of geometry optimization using shape deformation techniques. This design procedure allows for modelling complex 3D geometries which can be fabricated by additive manufacturing (AM). Shape deforming operations are based on radial basis function (RBF) interpolation and are integrated into an electromagnetic field simulator based on the 3D finiteelement method (FEM)....
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Within- and between-firm wage inequalities and trade integration in GVC
PublicationThis paper examines between- (inter) and within- (intra) firm wage inequality using rich employer-employee data for 12 European countries. We confirm that much overall wage inequality is observed within sectors and within occupations. The share of the within- and between-firm components in overall wage inequality varies across countries. We estimate the link between involvement in global value chains (GVCs) and wages differentiating...
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Effects of Noncontact Shoulder Tool Velocities on Friction Stir Joining of Polyamide 6 (PA6)
PublicationIn this study, the effects of the traverse and rotational velocities of the noncontact shoulder tool on the heat generation and heated flux during the friction stir joining of high-density polyamide 6 (PA6) polymer were investigated. The computational fluid dynamics (CFD) method was employed to simulate the thermomechanical phenomena during the friction stir joining (FSJ) process of PA6. A developed model was used to consider the...
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Instrumented end notched flexure - Crack propagation and process zonemonitoring Part II: Data reduction and experimental
PublicationA mode II instrumented end notched flexure three point bending (ENF) adhesion test is described. The adhesive joint consists of two aluminium alloy (AW7075-T6) plates bonded with a structural epoxy adhesive (Hysol EA 9395™). Strain gauges are attached to the outer surface (backface) of the substrates in the lengthwise direction to measure local surface strain during crack propagation. Simultaneously, load/displacement measurements...
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Zmiany temperatury wody powierzchniowej na morzach Arktyki Rosyjskiej i ich konsekwencje dla żeglugi na Północnej Drodze Morskiej
PublicationPraca omawia zmiany średniej miesięcznej temperatury wody powierzchniowej na morzach Arktyki Rosyjskiej w latach 1979-2016. Stwierdzono, że w badanym okresie następował powolny wzrost SST. Jednakże tylko na Morzu Barentsa był on istotny statystycznie we wszystkich miesiącach roku (poza marcem w SE części tego morza), a w zachodniej części Morza Czukockiego w okresie od czerwca do grudnia. W dalszym ciągu na wszystkich morzach,...
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Preliminary estimation of groundwater recharge on Brda river outwash plain
PublicationEstimation of groundwater recharge is one of the most challenging subjects in hydrogeology. It is a critical factor influencing the pollution migration, assessment of aquifer vulnerability to contamination, small-scale groundwater budget calculation, modeling of nutrient cycling and detailed flow path calculations. In Poland an infiltration rate method is widely used, which depends on a system of rate coefficients referring to...
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Combining Computational Fluid Dynamics with a Biokinetic Model for Predicting Ammonia and Phosphate Behavior in Aeration Tanks
PublicationThe aim of this study was to use computational fluid dynamics for predicting the behavior of reactive pollutants (ammonia and phosphate) in the aerobic zone of the bioreactor located at the Wschod wastewater treatment plant in Gdansk, Poland. The one-dimensional advection-dispersion equation was combined with simple biokinetic models incorporating the Monod-type expressions as source terms for the two pollutants. The problem was...
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Generalized access control in hierarchical computer network
PublicationThe paper presents the design of the security layer for a distributed system located in the multizone hierarchical computer network. Depending on the zone from which a client’s request comes to the system and the type of the request, it will be either authorized or rejected. There is one common layer for the access to all the business services and interactions between them. Unlike the commonly used RBAC model, this system enforces...
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HMSE: A tool for coupling MODFLOW and HYDRUS-1D computer programs
PublicationA new software HMSE has been developed to facilitate external coupling between two well-known programs for subsurface flow modeling: MODFLOW-2005 (saturated zone flow) and HYDRUS-1D (unsaturated zone flow). Two coupling schemes have been implemented. In the first case the groundwater recharge flux is calculated by HYDRUS-1D assuming a fixed water table position and then passed to MODFLOW input files. In the second case the water...
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Ocena zasobów oraz weryfikacja granic obszaru ochronnego GZWP nr 133 Młotkowo za pomocą numerycznego modelu przepływu wód podziemnych
PublicationModel Głównego Zbiornika Wód Podziemnych powstał w celu dokonania oceny dostępnych zasobów wód oraz zweryfikowania granic strefy ochronnej. GZWP Młotkowo jest położony w południowej części Pojezierza Krajeńskiego. Ze względu na konieczność weryfikacji granic zbiornika wyznaczonych przez Kleczkowskiego i in. (1990) do badań modelowych przyjęto obszar cztery razy większy niż rozmiar GZWP. W celu osiągnięcia najbardziej wiarygodnych...
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Mechanizmy bezpieczeństwa w strefie C systemu netBaltic
PublicationW artykule zaprezentowano rozwiązania zaimplementowane do zabezpieczania komunikacji w warunkach sporadycznej i nieciągłej łączności (Delay Tolerant Networking – DTN) w systemie netBaltic - charakterystycznej dla strefy C tego systemu. Ze względu na dużą różnorodność rozważanych mechanizmów komunikacyjnych, architektura bezpieczeństwa całego systemu została podzielona na kilka elementów – infrastrukturę klucza publicznego (PKI),...
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Bead-on-plate welding on S235JR steel by underwater local dry chamber process
PublicationThe article presents the results of the effect of parameters of underwater local dry chamber welding on the properties of padding welds. The effect of heat input and the type of shielding gas on the structure and hardness of welds was established. the functions for estimating the maximum hardness of the heat affected zone have been also elaborated.
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Treatment of Odontogenic Maxillary Sinusitis with the Use of Growth Factors in Advanced Platelet-Rich Fibrin for Immediate Closure of Oro-Antral Communication: A Case Report
PublicationChronic odontogenic maxillary sinusitis (COMS), a prolonged inflammation of the maxillary sinus lasting over 12 weeks, is often a result of periapical lesions, marginal periodontitis, and complications like oro-antral communication (OAC) and fistula (OAF). OAC, commonly emerging post-teeth extraction in the lateral maxilla, lacks documented treatments using advanced platelet-rich fibrin (A-PRF). This study evaluates A-PRF’s efficacy...
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Working Conditions in the Context of Global Value Chains and Routinisation: An Example of Polish Workers
PublicationThe paper aims to explore the linkages between global production fragmentation, routinisation and the well-being of workers in Poland. In particular, the focus is placed on the selected measures of working conditions, such as the social environment, work intensity, and working time quality to examine their dependence on involvement in international trade and the routinisation level. We merge individual data describing the working...
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STABILITY AND LOAD BEARING CAPACITY OF A BARS WITH BUILT UP CROSS SECTION AND ELASTIC SUPPORTS
PublicationThe present paper is devoted to the numerical analysis and experimental tests of compressed bars with built–up cross section which are commonly used as a top chord of the roof trusses. The significant impact on carrying capacity for that kind of elements in case of out-of-plane buckling is appropriate choice of battens which are used to provide interaction between separate members. Linear buckling analysis results and nonlinear static...
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Die Sandgrube „Köplitz“ – ein interessanter geologischer Aufschluss am Nordwestrand der Schmiedeberger Stauchendmoräne
PublicationDie Kiessandgrube Köplitz ermöglicht einen Einblick in die komplizierten, durch glazidynamische Überprägung gekennzeichneten geologischen Lagerungsverhältnisse im Bereich der Schmiedeberger Stauchendmoräne. Anhand neuer Geländedokumentationen wird ein kleiner Eindruck vom komplizierten injektiven „Fließfalten-Schuppenbau“ der Stauchendmoräne vermittelt. Die steil aufgerichteten, aus tertiären (Untermiozän bis Oligozän) und quartären...
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Methodology for Carrying Out Measurements of the Tombolo Geomorphic Landform Using Unmanned Aerial and Surface Vehicles near Sopot Pier, Poland
PublicationThe human impact on the ecosystem has been particularly evident in the last century; it transforms the Earth’s surface on an unprecedented scale and brings about irreversible changes. One example is an oceanographic phenomenon known as a tombolo, i.e., a narrow belt connecting the mainland with an island lying near the shore formed as a result of sand and gravel being deposited by sea currents. The phenomenon contributes to an...
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Present state of sewage and wastewater treatment plants in the polish coast of Baltic Sea
PublicationIn the paper the state of art of wastewater management in four zones of Polish Baltic Sea coast: the Vistula Lagoon, the Bay of Gdansk and Bay of Puck, the open sea zone and the Szczecin Lagoon, is discussed. Hydrological characteristics of these four zones as well as characteristics and operation effectiveness of wastewater treatment plants (WWTPs) located there, are presented.
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Properties of Composite Oxide Layers on The Ti13Nb13Zr Alloy
PublicationThe development of composite oxide layers on the Ti13Nb13Zr alloy, their structure and properties have been demonstrated. Two subsequent methods were applied to prepare the composite layers. During the first stage gas oxidation produced a solid oxide layer, and subsequently oxide nanotubes were produced by using an electrochemical method. Scanning electron microscopy (SEM), chemical analysis, energy dispersive X-ray spectroscopy...
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Effect of Impoundment on Physico-chemical Properties of Water in the Flowing through stream, the Case of the Turawa Reservoir
PublicationThe Turawa reservoir is one of the most important storage reservoirs in Poland. Quite many physico-chemical parameters of water in the reservoir itself and also in the Mała Panew, the river flowing through the reservoir were measured at various periods of the year. Measuring and sampling points were situated at the river inflow, over the reservoir, and at the river outflow. The parameters included temperature, electrical conductivity,...
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Assessment of crack resistance of S355J2+N steel according to SEP 1390 standard
PublicationThe aim of the study was to evaluate the weldability of S355J2+N steel by bending test according to SEP 1390. In the specimen from S355J2+N steel 3 external cracks were found, 1 of which were stopped in the fusion line and 2 in heat affected zone. Results of bending test for investigated grade of steel are positive.
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ZINTEGROWANE ZARZĄDZANIE STREFĄ PRZYBRZEŻNĄ ORAZ URBANISTYKA – PROJEKT NOWYCH SPECJALNOŚCI NA KIERUNKU GOSPODARKA PRZESTRZENNA NA POLITECHNICE GDAŃSKIEJ
PublicationNa studiach II stopnia na kierunku gospodarka przestrzenna na Wydziale Architektury Politechniki Gdańskiej w 2017 r. otwierane są dwie specjalności: urbanistyka i zintegrowane zarządzanie strefą przybrzeżną. Trzon programu studiów dla obu specjalności jest wspólny i oparty na dotychczasowych standardach kształcenia na tym kierunku. Specjalność zintegrowane zarządzanie strefą przybrzeżną jest odpowiedzią na konieczność wprowadzenia...
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Application of BDD thin film electrode for electrochemical decomposition of heterogeneous aromatic compounds
PublicationThe aim of the presented study is to investigate the applicability of electrochemical oxidation of aromatic compounds containing heteroatoms, e.g. waste from production of pesticides or pharmaceutics, at a borondoped diamond (BDD) electrode. The BDD electrodes were synthesized by microwave plasma enhanced chemical vapour deposition (MW PE CVD). Investigation of the electrode surface by optical microscopy and scanning electron microscopy...
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The effects of selected factors on regional road fatalities – analysis of the Łódź region
PublicationAnalysis of regional accident records shows that a country’s national road safety programme does not have the same effect in each of its regions. What may be a serious problem in one region may be of marginal significance in another. Polish and international experience shows that main risk groups and types of accidents related to the level of development and quality of the road network differ from region to region. The conclusion...
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An in situ technique for the assessment of adhesive properties of a joint under load
PublicationSlow crack propagation in adhesive bonded joints has been characterised using an asymmetric wedge test. Crack position was evaluated from strain gauge measurements, both in the debonded partof the joint and in the bonded zone. Test temperature was changed during loading, giving insight into bond evolution. The technique allows accurate, and virtually continuous, determination of crack position to be made, and therefore the evaluation...
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Effect of Pin Shape on Thermal History of Aluminum-Steel Friction Stir Welded Joint: Computational Fluid Dynamic Modeling and Validation
PublicationThis article studied the effects of pin angle on heat generation and temperature distribution during friction stir welding (FSW) of AA1100 aluminum alloy and St-14 low carbon steel. A validated computational fluid dynamics (CFD) model was implemented to simulate the FSW process. Scanning electron microscopy (SEM) was employed in order to investigate internal materials’ flow. Simulation results revealed that the mechanical work...
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Shear band evolution phenomena in direct shear test modelled with DEM.
PublicationA direct shear test is widely used in the geotechnical engineering field. It is an easy and quick test to measure the shear properties of soil. This test often replaces more expensive and difficult tri-axial shear test. Despite that the direct shear test is known and used for a long time, it is still not well investigated at the grain scale. This paper deals with the micro behaviour of the cohesionless sand inside the direct shear...
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Characterizing surface and air temperature in the Baltic Sea coastal area using remote sensing techniques and GIS
PublicationEstimation of surface temperature using multispectral imagery retrieved from satellite sensors constitutes several problems in terms of accuracy, accessibility, quality and evaluation. In order to obtain accurate results, currently utilized methods rely on removing atmospheric fluctuations in separate spectral windows, applying atmospheric corrections or utilizing additional information related to atmosphere or surface characteristics...
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Solvent-Free Synthesis of Phosphonic Graphene Derivative and Its Application in Mercury Ions Adsorption
PublicationFunctionalized graphene was efficiently prepared through ball-milling of graphite in the presence of dry ice. In this way, oxygen functional groups were introduced into material. The material was further chemically functionalized to produce graphene derivative with phosphonic groups. The obtained materials were characterized by spectroscopic and microscopic methods, along with thermogravimetric analysis. The newly developed material...
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Impact of climate change on groundwater recharge in shallow young glacial aquifers in northern Poland
PublicationWe investigated the influence of climate change in the period 1951–2020 on shallow aquifers in the Brda and Wda outwash plains (Pomeranian Region, Northern Poland). There was a significant temperature rise (0.3 °C/10 years), which accelerated after 1980 (0.66 °C/10 years). Precipitation became increasingly irregular – extremely rainy years occurred right after or before extremely dry years, and intensive rainfall events became...
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Solubility of Methane in Water: Some Useful Results for Hydrate Nucleation
PublicationIn this paper, the solubility of methane in water along the 400 bar isobar is determined by computer simulations using the TIP4P/Ice force field for water and a simple LJ model for methane. In particular, the solubility of methane in water when in contact with the gas phase and the solubility of methane in water when in contact with the hydrate has been determined. The solubility of methane in a gas–liquid system decreases as temperature...
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Diversity and distribution of Tardigrada in Arctic cryoconite holes
PublicationDespite the fact that glaciers and ice sheets have been monitored for more than a century, knowledge on the glacial biota remains poor. Cryoconite holes are water-filled reservoirs on a glacier’s surface and one of the most extreme ecosystems for microinvertebrates. Tardigrada, also known as water bears, are a common inhabitant of cryoconite holes. In this paper we present novel data on the morphology, diversity, distribution and...
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Release and Transport of Toxic, Mobile Organic Compounds (Formaldehyde and Phenols) on an Arctic Glacier
PublicationAs a result of current deglaciation, the chemical cycles of many compounds, including toxic formaldehyde and phenols, are changing. However, the processes by which these chemicals are released have yet to be studied in situ. Here, we quantify fluxes of HCHO and phenols in a glacial catchment within one summer season, obtaining a net release from the glacier of 0.106 · 106 g formaldehyde and 0.255 · 106 g phenols, which can be interpreted...
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Bimodal deep learning model for subjectively enhanced emotion classification in films
PublicationThis research delves into the concept of color grading in film, focusing on how color influences the emotional response of the audience. The study commenced by recalling state-of-the-art works that process audio-video signals and associated emotions by machine learning. Then, assumptions of subjective tests for refining and validating an emotion model for assigning specific emotional labels to selected film excerpts were presented....
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Evolution of magnetic and transport properties in (Cr1−xMnx)2AlC MAX-phase synthesized by arc melting technique
PublicationHerein we initiate a comeback to the arc melting technique to produce MAX-phase solid solutions. Bulk samples of (Cr1−xMnx)2AlC MAX-phase with X = 0, 0.025, 0.05 and 0.1 were synthesized and studied by means of X-ray diffractometry, scanning electron microscopy in combination with energy-dispersive X-ray spectroscopy. Samples were established to be homogeneous with an incorporation of Cr7C3, AlCr2 and Al2O3 secondary phases which...
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Improvements and Spatial Dependencies in Energy Transition Measures
PublicationThis article aims to improve one of the newest energy transition measures—the WorldEconomic Forum WEF Energy Transition Index (ETI) and find its driving forces. This paper proposesa new approach to correct the ETI structure, i.e., sensitivity analysis, which allows assessing theaccuracy of variable weights. Moreover, the novelty of the paper is the use the spatial error modelsto estimate determinants of the energy transition on...
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Investigation of ecological parameters of a gas turbine combustion chamber with steam injection for the floating production, storage, and offloading vessel
PublicationThe article is dedicated to the investigation of the possibility of using the contact type gas turbine cycle with steam injection into the combustion chamber for the floating production, storage, and offloading vessel in order to increase the specific power and efficiency and reduce emissions of toxic components. A new approach is proposed, associated with the use of the two-stage injection of superheated steam into a gas turbine...
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Activated Tungsten Inert Gas Weld Characteristics of P91 Joint for Advanced Ultra Supercritical Power Plant Applications
PublicationActivated Tungsten Inert Gas (A-TIG) welding, a variant of tungsten inert gas (TIG) welding, was used for welding P91. In Generation IV power plants, P91 welds are prone to premature failure due to the presence and formation of brittle phases and creep at high temperatures. When performing A-TIG welding, the flux composition plays a role in the reversal of the Marangoni flow in the weld pool, which ultimately determines the level...
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Assessment of unusual failure in crankshaft of heavy-duty truck engine
PublicationThe unusual premature failure of a heavy-duty truck engine crankshaft has been the subject of a rigorous study, and this manuscript describes it in detail. The failure was happened to begin with the growth of the crack from the surface defects, in the form of the clusters of non-metallic inclusions, in the lubrication hole zone of the first main journal, which was the stress concentration zone. A series of experiments including...
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INVESTIGATION OF THE CHARACTERISTICS OF A LOWEMISSION GAS TURBINE COMBUSTION CHAMBER OPERATING ON A MIXTURE OF NATURAL GAS AND HYDROGEN
PublicationT his article is devoted to the investigation of the characteristics of a low-emission gas turbine combustion chamber, which can be used in Floating Production, Storage and Offloading (FPSO) vessels and operates on a mixture of natural gas and hydrogen. A new approach is proposed for modelling the processes of burning out a mixture of natural gas with hydrogen under preliminary mixing conditions in gaseous fuel with an oxidizer...
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A coupled constitutive model for fracture in plain concrete based on continuum theory with non-local softening and eXtended Finite Element Method
PublicationThe paper presents a constitutive model for concrete which combines a continuous and discontinuous fracture description. In a continuum regime, two different constitutive laws were used. First, a plasticity model with a Rankine failure criterion and an associated fl ow rule was used. Second, a constitutive law based on isotropic damage mechanics was formulated. In order to capture the width of a localized zone and to obtain mesh-independent...
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Analiza porównawcza wybranych hierarchicznych algorytmów trasowania w sieciach ad hoc
PublicationW referacie przybliżono ogólną zasadę działania algorytmów hierarchicznych stosowanych w sieciach ad hoc. Szczegółowo omówiono dwa hierarchiczne protokoły trasowania: Cluster Based Routing Protocol oraz Zone Routing Protocol. Osobny punkt referatu poświęcono analizie porównawczej obu protokołów. W podsumowaniu przeanalizowano zasadność zastosowania wspomnianych protokołów w Zautomatyzowanym Systemie Radarowego Nadzoru Polskich...
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Polish- Russian Cooperation of Pomorskie Province
PublicationPolish-Russian Cooperation of Pomorskie Province commenced in 1999 and was based on the intergovernmental agreements. The new agreement, executed between the authorities of the Pomeranian Province and Kaliningrad Oblast in 2002, provided for cooperation in many areas. The contacts between the partners were dominated by economic cooperation. The Polish-Russian cooperation stopped with Polish accession to the Schengen zone. Cooperation...
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Bearing estimation using double frequency reassignment for a linear passive array
PublicationThe paper demonstrates the use of frequency reassignment for bearing estimation. For this task, signals derived from a linear equispaced passive array are used. The presented method makes use of Fourier transformation based spatial spectrum estimation. It is further developed through the application of two-dimensional reassignment, which leads to obtaining highly concentrated energy distributions in the joint frequency-angle domain...
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The role of analytical chemistry in the study of the Anthropocene
PublicationThe term “Anthropocene” refers to not yet formalized epoch of geologic time during which geologic processes have been dominated by the human impact. This impact takes on many forms. Biological, physical and chemical changes to the Earth System caused by anthropogenic activity are recorded in natural archives either as new fossil assemblages (neobiota), anthropogenic deposits or a wide variety of pollutants emitted to the environment....
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Wyniki badań parkingowych w obszarze Śródmieścia Gdyni.
PublicationW referacie przedstawiono metodykę i wyniki badań parkingowych, które przeprowadzono w obszarze Strefy Płatnego Parkowania w Gdyni w ramach projektu CIVITAS DYN@MO. Badania prowadzone były w celu możliwości określenia wpływu graniczenia/zamknięcia ruchu na wybranych ciągach ulic.
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Study on Microstructure and Mechanical Properties of Laser Welded Dissimilar Joint of P91 Steel and INCOLOY 800HT Nickel Alloy
PublicationThis investigation attempts to explore the weld characteristics of a laser welded dissimilar joint of ferritic/martensitic 9Cr-1Mo-V-Nb (P91) steel and Incoloy 800HT austenitic nickel alloy. This dissimilar joint is essential in power generating nuclear and thermal plants operating at 600–650 °C. In such critical operating conditions, it is essential for a dissimilar joint to preserve its characteristics and be free from any kind...
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Unfolding new values in the landscape of conflict
PublicationThe main objective of the paper is to investigate how the conflict quality of landscape can be used as its asset and potential for creating new values. Like mediation between different overlapping archaeologies offers a basis for the perception of place in the chronology of time, the mediation between conflicted areas creates a capacious zone for enhancing the unique quality of landscape in its architectural, social, cultural and...
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Offshore benthic habitat mapping based on object-based image analysis and geomorphometric approach. A case study from the Slupsk Bank, Southern Baltic Sea
PublicationBenthic habitat mapping is a rapidly growing field of underwater remote sensing studies. This study provides the first insight for high-resolution hydroacoustic surveys in the Slupsk Bank Natura 2000 site, one of the most valuable sites in the Polish Exclusive Zone of the Southern Baltic. This study developed a quick and transparent, automatic classification workflow based on multibeam echosounder and side-scan sonar surveys to...
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An updated method identifying collision-prone locations for ships. A case study for oil tankers navigating in the Gulf of Finland
PublicationTo ensure the risk level associated with continuously increasing maritime traffic through particularly sensitive sea areas remains at acceptable level, a periodic risk assessment needs to be carried out by the relevant authorities. As a part of such assessment, allowing for proactive countermeasures to mitigate risk, the frequency of accidents is estimated along with the assessment of geographical locations where the accidents...