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Search results for: Borophene flakes
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Acceleration of decision making in sound event recognition employing supercomputing cluster
PublicationParallel processing of audio data streams is introduced to shorten the decision making time in hazardous sound event recognition. A supercomputing cluster environment with a framework dedicated to processing multimedia data streams in real time is used. The sound event recognition algorithms employed are based on detecting foreground events, calculating their features in short time frames, and classifying the events with Support...
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A Method for Optimising the Blade Profile in Kaplan Turbine
PublicationThis paper introduces a method of blade profile optimisation for Kaplan-type turbines, based on modelling the interaction between rotor and stator blades. Rotor and stator blade geometry is described mathematically by means of a midline curve and thickness distribution. Genetic algorithms are then used to find a global optimum that minimises the loss coefficient. This allows for variety of possible blade shapes and configurations....
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MACHINE VISION DETECTION OF THE CIRCULAR SAW VIBRATIONS
PublicationDynamical properties of rotating circular saw blades are crucial for both production quality and personnel safety. This paper presents a novel method for monitoring circular saw vibrations and deviations. A machine vision system uses a camera and a laser line projected on the saw’s surface to estimate vibration range. Changes of the dynamic behaviour of the saw were measured as a function of the rotational speed. The critical rotational...
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Topology Discovery of Hierarchical Ethernet LANs without SNMP support
PublicationThis paper presents an algorithm that allows for discovery of layer-2 hierarchical Ethernet network topology using agents running on selected end nodes. No SNMP, MIB, hardware, firmware, or operating system-level software modification is required. The method is based on transmission of customized Ethernet frames among installed software agents. It can be used to discover the topology of LAN or one VLAN segment as long as no MAC...
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Numerical analysis of the carpentry joints applied in the traditional wooden structures
PublicationThe paper concerns the numerical analysis of the carpentry joints made from spruce wood. The material parameters of the wood have been calculated on the basis of nine independent material constants (an orthotropic material). The contact zone between the individual elements of the connection has been determined using Contact Tables in the MSC.Marc software. Five types of carpentry joints have been analyzed. The main aim of the research...
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THERMODYNAMIC ANALYSIS OF A GENERATION IV SCWR NUCLEAR POWER PLANT CYCLE
PublicationThis article presents a flow and thermodynamic analysis of a Generation IV nuclear cycle. An SCWR (Supercritical water reactor) is a high temperature and high pressure reactor that uses water at a temperature above its thermodynamic critical point as the working fluid. The cycle used for the calculations consists of one interstage superheater and 7 regenerative heat exchangers. Division pressure was optimized in view of the cycle efficiency,...
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Assessment of protective properties of rubber lining in absorbers of flue gas desulphurization systems.
PublicationResults of research on degradation of rubber lining which is the main protection of absorbers in flue gas desulphurization (FGD) systems were presented. The power plant where the system operated is lignite-fired. Owing to measurements using electrochemical impedance spectroscopy and gravimetric determination of water content in the lining, the areas of the system which are most exposed to degradation were shown. The results obtained...
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Electrostatic interface recombination in the system of disordered materials characterized by different permittivities
PublicationWe report on the analysis of an electrostatic interface recombination in a system consisting of disordered organic materials. This process is a consequence of the polarization effect which takes place at the interface of two phases characterized by different permittivities. In this paper, the impact of tail and deep localized states on the recombination order is demonstrated. We also discuss the influence of temperature on this...
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A New Approach for Investigating the Impact of Pesticides and Nutrient Flux from Agricultural Holdings and Land-Use Structures on Baltic Sea Coastal Waters
PublicationKnowledge related to land-use management impacts on the Baltic Sea ecosystem is limited. The constant release of pollutants into water bodies has resulted in water quality degradation. Therefore, only the innovative approaches integrated with research will provide accurate solutions and methods for proper environment management and will enable understanding and prediction of the impacts of land-use in the Baltic Sea region. Modelling...
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TiO2 nanotube arrays-based reactor for photocatalytic oxidation of parabens mixtures in ultrapure water: Effects of photocatalyst properties, operational parameters and light source
PublicationSelf-organized TiO2 nanotubes as immobilized photocatalysts were evaluated in detail for the photocatalytic degradation of parabens mixtures from ultrapure water. This kind of approach can be a very suitable option for emerging contaminants degradation considering the possibility of the catalyst reuse and recovery which will be simpler than when catalytic powders are used. The anodization method was applied for the TiO2 nanotubes...
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Identification of Emotional States Using Phantom Miro M310 Camera
PublicationThe purpose of this paper is to present the possibilities associated with the use of remote sensing methods in identifying human emotional states, and to present the results of the research conducted by the authors in this field. The studies presented involved the use of advanced image analysis to identify areas on the human face that change their activity along with emotional expression. Most of the research carried out in laboratories...
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Sensorless Field Oriented Control of Five Phase Induction Motor with Third Harmonic Injection
PublicationIn this paper, a sensorless field oriented control system of five-phase induction machine with the 3rd harmonic rotor flux is presented. Two vector models, α1-β1 and α3-β3, were transformed into d1-q1, d3-q3 models oriented in rotating frames, which correspond to the 1st and 3rd harmonic plane respectively. The authors proposed the linearization of the model in d-q coordinate frames by introducing a new variable “x” which is proportional...
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Neoclassical Navier–Stokes Equations Considering the Gyftopoulos–Beretta Exposition of Thermodynamics
PublicationThe seminal Navier-Stokes equations were stated even before the creation of the foundations of thermodynamics and its first and second laws. There is a widespread opinion in the literature on thermodynamic cycles that the Navier-Stokes equations cannot be taken as a thermodynamically correct model of a local "working fluid", which would be able to describe the conversion of "heating" into "working" (Carnot's type cycles) and vice...
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Zanikanie. Cmentarze menonickie w przestrzeni kulturowej Żuław
PublicationCmentarze menonickie są jednym z elementów wielonarodowej mozaiki kulturowej, jaką można odnaleźć na Żuławach Wiślanych. Obecne są w krajobrazie od ponad dwustu pięćdziesięciu lat.Celem publikacji jest przedstawienie współczesnej historii menonickich cmentarzy i obiektów sakralnych. Oparte zostało na badaniach terenowych nekropolii i lapidariów Delty Wisły w Cyganku-Żelichowie, Fiszewie, Jezierniku, Niedźwiedziówce, Pordenowie,...
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Suitability study of hybrid model of electrodynamic actuator
PublicationThis paper presents the proposal of the hybrid circuit-field model of an electrodynamic actuator. The field model uses the inductor current as the input data which is obtained from the circuit model or experimentally. The field model implemented using the FLUX program makes it possible to easily determine the pressure distribution acting on the disc. The results have been verified experimentally.
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Proposition of the steam turbine governor structure modification
PublicationThere is considered the steam turbine governor operation during defense and restoration of the power system. It points out weaknesses of currently used governor structures. The new controller is proposed, that takes advantages of those curently used. The new controller allows for more effective control of the turbine in emergency situations, at frequencies much different from the nominal value.
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New Indoor Positioning Algorithm for Distance Measurements
PublicationIn the paper a new indoor positioning algorithm is presented. This algorithm takes into account selected features of radio wave propagation in indoor environment. This results in improvement in accuracy of calculated position estimates. A comparative analysis of this new algorithm with Chan and Foy algorithms was made and described in the paper. This comparative analysis was made with utilization of real radio distance measurements.
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The Issues of Reactive Power Compensation in High-voltage Transmission Lines
PublicationThis paper discusses the selection of compensation shunt reactors for a double-circuit 400 kV transmission line using the example of the newly built Elk Bis – Alytus transmission line. The analysis takes into account various conditions of the power system. The published results relate to voltage levels in steady states and during switching processes and short circuits.
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Contaminants in airport runoff water
PublicationDespite the many positives ensuing from the rapid expansion of the air transport sector, airport operations as a whole are a substantial source of environmental pollution.Increases in aviation developments have serious consequences on the surrounding air, soil and water bodies like lakes, rivers and ground water. The present work deals with the determination of polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls...
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Degradation of ferritic X10CrAlSi18 stainless steel caused by slurry
PublicationThe slurry erosion tests of ferritic X10CrAlSi18 steel were carried out using a slurry pot device. In order to investigate the erosion process, two series of tests were performed: first one with a constant impact velocity of 5 m/s, 7 m/s and 9 m/s and the second one, during which the impact velocity was changed after every exposure. During each test, an influence of test conditions on volume loss, surface hardness and roughness...
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APPLYING RANSAC ALGORITHM FOR FITTING SCANNING STRIPS FROM AIRBORNE LASER SCANNING
PublicationDuring the development of the data acquired by airborne laser scanning the important issue is the fitting and georeferencing of ALS point clouds by means of the tie surfaces and the reference planes. The process of scanning strips adjustment is based on mutual integration of point clouds (scanning strips) and their adaptation to the reference planes.In simultaneous adjustment all strips are combined into one geometrically coherent...
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Ad hoc prayer spaces – a challenge of the architecture of the 21th century
PublicationThis article considers the problem of arranging places of prayer in the vicinity of universities and dormitories. A survey was conducted among students living in the dormitories of the Gdańsk University of Technology in order to determine if there was a real need to arrange such spaces. Subsequently, examples of temporary chapels designed in the last 20 years in Western European countries were presented. Analysis of the selected...
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Study of Metrological Properties of Voltammetric Electrodes in the Time Domain
PublicationMetrological properties of voltammetric electrodes, in the situation where on their surface an electrochemical reaction of oxidizing/reduction takes place, were analyzed in this chapter. The properties of electrodes on which a reaction controlled by ion transport process takes place were taken into consideration. Also, it was analyzed how the electrode’s shape and the voltage polarizing the electrode influence this electrode’s...
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Video Semantic Analysis Framework based on Run-time Production Rules - Towards Cognitive Vision
PublicationThis paper proposes a service-oriented architecture for video analysis which separates object detection from event recognition. Our aim is to introduce new tools to be considered in the pathway towards Cognitive Vision as a support for classical Computer Vision techniques that have been broadly used by the scientific community. In the article, we particularly focus in solving some of the reported scalability issues found in current...
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AN EXPERIMENTAL AND NUMERICAL STUDY ON THE PERFORMANCE OF AN INNOVATIVE VERTICAL-AXIS WIND TURBINE
PublicationThis paper introduces the innovative modification of the Savonius wind turbine being able to significantly increase efficiency in comparison with the classic design. This innovative design is equipped with a stator directing the flow. The presence of the stator increases the active surface area and generates higher torques acting on a shaft. Additionally, it makes it possible to take better advantage of wind energy and compensate...
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Coupled Urban Areas Inundation Model with Interaction Between Storm Water System and Surface Flow - Case Study of Sea Level Impact on Seaside Areas Flooding
PublicationInundations are becoming more frequent than ever. What is connected with increasing area of impervious surface in cities. This makes predicting urban flooding and its scale especially important. At the seaside we observe additional conditions such as sea level that makes accurate numerical modelling of issue even harder. With complex approach to the matter which is simultaneous calculation of storm water conduit flow and overland...
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Towards spectroscopic monitoring of photoelectrodes: In-situ Raman photoelectrochemistry of a TiO2/prussian blue photoanode
PublicationHere, novel in-situ Raman photoelectrochemical measurements are performed. The obtained results have proved that it is possible to track the progress of a photoelectrochemical reaction that takes place on a semiconducting electrode using the spectroscopic method. As an exemplary system, the Ti/TiO2/Prussian blue electrode is investigated. Since TiO2 is an n-type semiconductor, it cannot act as an efficient anode in dark conditions....
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Metal-Organic Framework (MOF)/Epoxy Coatings: A Review
PublicationEpoxy coatings are developing fast in order to meet the requirements of advanced materials and systems. Progress in nanomaterial science and technology has opened a new era of engineering for tailoring the bulk and surface properties of organic coatings, e.g., adhesion to the substrate, anti-corrosion, mechanical, flame-retardant, and self-healing characteristics. Metal-organic frameworks (MOFs), a subclass of coordinative polymers...
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Equal Baseline Camera Array—Calibration, Testbed and Applications
PublicationThis paper presents research on 3D scanning by taking advantage of a camera array consisting of up to five adjacent cameras. Such an array makes it possible to make a disparity map with a higher precision than a stereo camera, however it preserves the advantages of a stereo camera such as a possibility to operate in wide range of distances and in highly illuminated areas. In an outdoor environment, the array is a competitive alternative...
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Application of method of differential magnetometric system for detection of sunken objects
PublicationThis paper presents a magnetometric system with scalar sensors mounted on two independent platforms, which is used to detect sunken shipwrecks. Increasing the distance between the sensors allows for more precise measurement of the difference in the magnetic induction module than in the case of sensors mounted e.g. on the aeroplane’s wings. This type of system makes it possible to enlarge detection range of the sunken wrecks.
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Investigation of rotational state-changing collisions of C2N− ions with helium
PublicationThe cross sections for rotational inelastic collisions between atoms and a molecular anion can be very large, if the anion has a dipole moment. This makes molecular anions very efficient in cooling atomic gases. We address rotational inelastic collisions of Helium atoms with the molecular anion C2N–. Here we present preliminary calculations of the potential energy surface.
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PARTICLE SIZE ANALYSIS OF SUSPENSIONS IN REMOVING OF ORGANIC MATTER AND PHOSPHORUS FROM WASTEWATER AND SURFACE WATER
PublicationIn this paper the particle size of suspended solids in the removing of organic matter and phosphorus compounds from lake water and wastewater treated in the Ecological Treatment Systems (ETS) was analyzed. The invesigated materials were taken from two ETS located in Pomerania Region/Poland. Object in Swarzewo is 3rd stage of biological treatment of municipal wastewater, while object in Kartuzy has task to remove a phosphorus from...
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Particle size analysis of suspensions in removing of organic matter and phosphorus from waste water and surface water
PublicationIn this paper the particle size of suspended solids in the removing of organic matter and phosphorus compounds from lake- and waste- water treated in the Ecological Treatment Systems (ETS) was analyzed.The invesigated materials were taken from two ETS located in Pomerania Region/Poland. Object in Swarzewo is 3rd stage of biological treatment of municipal waste water, while object in Kartuzy has task to remove a phosphorus from...
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Image Classification Based on Video Segments
PublicationIn the dissertation a new method for improving the quality of classifications of images in video streams has been proposed and analyzed. In multiple fields concerning such a classification, the proposed algorithms focus on the analysis of single frames. This class of algorithms has been named OFA (One Frame Analyzed).In the dissertation, small segments of the video are considered and each image is analyzed in the context of its...
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Theoretical and experimental analysis of guided wave propagation in plate-like structures with sinusoidal thickness variations
PublicationGuided waves have attracted significant attention for non-destructive testing (NDT) and structural health monitoring (SHM) due to their ability to travel relatively long distances without significant energy loss combined with their sensitivity to even small defects. Therefore, they are commonly used in damage detection and localization applications. The main idea of incorporating guided waves in NDT and SHM is based on processing...
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Sensorless field oriented control for five-phase induction motors with third harmonic injection and fault insensitive feature
PublicationThe paper presents a solution for sensorless field oriented control (FOC) system for five-phase induction motors with improved rotor flux pattern. In order to obtain the advantages of a third harmonic injection with a quasi-trapezoidal flux shape, two vector models, α1–β1 and α3–β3, were transformed into d1– q1, d3– q3 rotating frames, which correlate to the 1st and 3rd harmonic plane respectively. A linearization approach of the...
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Damage Detection in the Wind Turbine Blade Using Root Mean Square and Experimental Modal Parameters
PublicationThe paper presents results of an experimental study related to a non-destructive diagnostic technique used for preliminary determination the location and size of delamination in composite coatings of wind turbine blades. The proposed method of damage detection is based on the analysis of the ten first mode shapes of bending vibrations, which correspond to displacements of rotor blades perpendicular to the rotor plane. Modal parameters...
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A fast procedure of stress state evaluation in magnetically anisotropic steels with the help of a probe with adjustable magnetizing field direction
PublicationThe paper presents a novel approach to the stress state evaluation issue. It deals with a strongly (magnetically) anisotropic materials for which a direct interpretation of the Barkhausen effect (BE) intensity would lead to erroneous results. In such a case one has to take into account both the measured BE intensity and the orientation of the magnetisation direction relative to the magnetic easy axis. For the in plane stress distribution...
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Investigation on the Sources and Impact of Trace Elements in the Annual Snowpack and the Firn in the Hansbreen (Southwest Spitsbergen)
PublicationWe present a thorough evaluation of the water soluble fraction of the trace element composition (Ca, Sr, Mg, Na, K, Li, B, Rb, U, Ni, Co, As, Cs, Cd, Mo, Se, Eu, Ba, V, Ge, Ga, Cr, Cr, P, Ti, Mn, Zr, Ce, Zn, Fe, Gd, Y, Pb, Bi, Yb, Al, Nb, Er, Nd, Dy, Sm, Ho, Th, La, Lu, Tm, Pr, Tb, Fe, In, Tl) and their fluxes in the annual snowpack and the firn of the Hansbreen (a tidewater glacier terminating in the Hornsund fjord, southwest...
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Determination of stepped plate thickness distribution using guided waves and compressed sensing approach
PublicationGuided waves recently have attracted significant interest as a very promising research area. The signals registered by a specially designed sensor network are processed to assess the state of the tested structure. Despite the constant development of novel damage detection algorithms employing guided waves, the phenomenon of wave propagation still needs detailed recognizing and understanding for the further progress of non-destructive...
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Narracje o świeżej traumie. Upamiętnianie ataków terrorystycznych w krajobrazie codziennym miast
PublicationRecent trauma Narratives: commemorating terrorist attacks in Everyday cityscape Contemporary city incidentally becomes a non-accidental target of acts violating the primary sense of security and safety. The fundamental assumptions about so- cial and interpersonal interactions that guarantee social life are severely disturbed. These events, primarily the ones related to terrorist attacks, leave in social memo- ry traces associated...
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The role of noble metals in TiO2 nanotubes for the abatement of parabens by photocatalysis, catalytic and photocatalytic ozonation
PublicationThe role of modified TiO2 nanotubes (TNTs) with noble metals was studied for photocatalysis, catalytic and photocatalytic ozonation of a paraben’s mixture. The TNTs were obtained by anodization and were modified by photodeposition with 0.25 mol% of Au, Pt or Pd. Results showed that solar photocatalysis led to higher degradation than UVA radiation, and under UVA radiation, the use of 3 Pt-TNTs (3 TNTs plates modified with Pt) and...
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Protokoły drzewa opinającego - ataki i metody obrony
PublicationW pracy przedstawiono sposoby ataków na sieci wykorzystujące realizacje drzewa opinającego STP (IEEE 802.1d i IEEE 802.1w a także modyfikacji STP wprowadzonych przez Cisco) oraz znane metody obrony przed atakami na STP. Zaproponowano także nową koncepcje obrony przed atakami mechanizmu STP wykorzystującą pole flags ramek BPDU.
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Thermal Decomposition of Carbamoyl Meldrum’s Acids: A Starting Point for the Preparation of 1,3-Oxazine Derivatives
PublicationThe ability to undergo [4 + 2] versus [2 + 2] cycloaddition was under investigation for ketenes thermally generated from carbamoyl Meldrum’s acid. Usually, 1,3-oxazino-5-carbamoylo-4,6-diones are formed when carbamoyl Meldrum’s acid reacts with imine. However, in some cases, a reaction takes an unexpected course, leading to the formation of tetraponerines alkaloids derivatives or cyclic iminoethers.
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Times Series Analysis Of Road Safety Trends At The Regional Level In Poland
PublicationThe paper presents possibility of applying a structural times series modeling with explanatory and intervention variables as a tool capable for explaining the changes in the monthly number of fatalities and seriously injured in traffic accidents. The analysis covers regional level and takes into consideration traffic accidents data of two regions: Pomorskie and Warmia-Mazury. In addition short-term forecasts for the two regions...
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RECENT ADVANCES IN GRAPHENE APPLICATION FOR ELECTRONIC SENSING
PublicationThe great interest in graphene is caused by its potential for constructing various sensors exhibiting excellent parameters. The high carrier mobility and the unique band structure of graphene makes it promising especially in the field-effect transistors (GFET) applications. In this article, recent advances of the selected graphene-based sensor applications were presented and the possible directions for further investigations were...
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Fast multi-objective optimization of antenna structures by means of data-driven surrogates and dimensionality reduction
PublicationDesign of contemporary antenna structures needs to account for several and often conflicting objectives. These are pertinent to both electrical and field properties of the antenna but also its geometry (e.g., footprint minimization). For practical reasons, especially to facilitate efficient optimization, single-objective formulations are most often employed, through either a priori preference articulation, objective aggregation,...
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The influence of position of the post or its absence on the performance of the cable barrier system
PublicationRoad safety barriers are used to increase safety in potentially dangerous places on the roads. They are designed and installed on the roads to prevent any vehicle from getting outside the travelled way or from entering the opposite lane of the road. Barriers, which are used on European roads, have to undergo full scale crash tests according to the EN 1317 standards. Nowadays as a supplement to real crash tests, numerical simulations...
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Suitability of LoRaWAN Technology for the Development of Maritime Applications
PublicationThe LoRaWAN Technology opens new possibilities for gathering and analysis of distributed data. In the paper we concentrate on its maritime usability which was tested by us in the period from June to August 2018. Measurements of the LoRaWAN network coverage in the Bay of Gdansk area were carried out. Various conditions and places were tested. The research was planned in such a way as to gradually increase the range and control the...
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Reliable method of assessing fracture properties of asymmetric bonded joints
PublicationTwo methods of assessing fracture properties of adhesive joints were studied. Two wedge tests: with continuous deflection and with force measurements were compared. Asymmetric geometry of the bonded joint was considered, i.e. two different plates of aluminium alloys: Al-Cu and Al-Mg, were bonded with epoxy DGEBA adhesive. The analytical model is shown to estimate the values of fracture properties: crack position and critical fracture...