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Wyniki wyszukiwania dla: 3d
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A numerical model to simulate the motion of a lifesaving module during its launching from the ship’s stern ramp
PublikacjaThe article presents a numerical model of object motion in six degrees of freedom (DoF) which is intended to be used to simulate 3D motion of a lifesaving module during its launching from a ship using a stern ramp in rough sea. The model, of relatively high complexity, takes into account both the motion of the ship on water in changing sea conditions, and the relative motion of the ramp with respect to the ship. The motion of the...
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Identyfikacja osób na podstawie cech twarzyz zastosowaniem logiki rozmytej
PublikacjaIstnieje wiele metod identyfikacji twarzyna podstawie zdjęcia, które pomimo swoich licznych zaletcharakteryzują się tym, że prawidłowa identyfikacja zależy odpodobnego w stosunku do zdjęcia znajdującego się w baziedanych oświetlenia, pozy czy miny identyfikowanej osoby.W artykule przedstawiono sposób na usuniecie ograniczeńistniejącego programu identyfikacyjnego Mug-Match Phantomas.Scharakteryzowano również założenia do metodypozwalającej...
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Efficient three-dimensional fluorescence measurements for characterization of binding properties in some plants
PublikacjaThe main aim of this research was to characterize some plants and to determine their similarities and differences, using spectroscopic methods. The interactions of soluble polyphenols of different plants with human serum albumin (HSA) were investigated by 3D-fluorescence. The obtained fluorescence results allow to classify the investigated plants according to their binding properties. The HSA-binding capacities of these plants...
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Multimateriałowe oraz wielokolorowe drukowanie wysokiej jakości części z żywic utwardzanych światłem UV w technologii PolyJet
PublikacjaMożliwość budowania multimateriałowych oraz wielokolorowych elementów stanowi ważny trend w rozwoju technologii żywicznych druku 3D. W niniejszym opracowaniu skupiono się na charakterystyce podstawowej metody przetwarzającej ciekłe fotopolimery – technologii PolyJet. Omówiono zasadę jej działania oraz najważniejsze aspekty procesu dotyczące m.in. parametrów drukarki, stosowanych struktur podporowych oraz rodzaju uzyskiwanej powierzchni...
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Mechanical Properties of Aluminium Bracket Strengthening
PublikacjaThe aim of the research is laboratory investigation of aluminium brackets employed to fasten lightweight curtain walls to building facilities. Tensile loads perpendicular to end plates (vertical) were applied here. The author focused on the solutions intended to increase the load-carrying capacity of aluminium brackets applying the plain washer form A (DIN 125; ISO 7089), plain washer with an outer diameter about 3d (DIN 9021;...
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The Usage of the BP-Layers Stereo Matching Algorithm with the EBCA Camera Set
PublikacjaThis paper is concerned with applying a stereo matching algorithm called BP-Layers to a set of many cameras. BP Layers is designed for obtaining disparity maps from stereo cameras. The algorithm takes advantage of convolutional natural networks. This paper presents using this algorithm with a set called Equal Baseline Camera Array. This set consists of up to five cameras with one central camera and other ones aground it. Such a...
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Buckling analyses of metal cylindrical silos containing bulk solids during filling
PublikacjaThe paper presents 3D results on stability of thin-walled cylindrical metal silos made of isotropic rolled and corrugated plates containing bulk solids. The behavior of bulk solids was described using a hypoplastic constitutive model. Nonlinear finite element (FE) analyses with both geometric and material nonlinearity were performed with a perfect and an imperfect silo shell wherein initial geometric imperfections were taken into...
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MODELLING OF CONCRETE FRACTURE AT AGGREGATE LEVEL USING DEM BASED ON X-RAY mu CT IMAGES OF INTERNAL STRUCTURE
PublikacjaThe paper describes two-dimensional meso-scale numerical results of fracture in notched concrete beams under quasi-static three-point bending. Concrete was modelled as a random heterogeneous 4-phase material composed of aggregate particles, cement matrix, interfacial transitional zones (ITZs) and air voids. As a numerical approach, the discrete element method (DEM) was used. The concrete micro-structure in calculations was directly...
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Możliwości poprawy sprawności pomp głębinowych HYDRO-VACUUM SA drogą zastosowania nowoczesnych komputerowych metod projektowania
PublikacjaW prezentacji omówiono algorytm postępowania jaki został zrealizowany przy modernizacji istniejącej konstrukcji pompy głębinowej. Modernizacji dokonano przy użyciu nowoczesnych metod komputerowych z wykorzystaniem własnego oprogramowania do obliczeń jedno i dwu-wymiarowych oraz komercyjnych programów CAD i do obliczeń przepływów 3D (Fluent). Porównano wyniki badań na konstrukcji rzeczywistej z badaniami numerycznymi konstrukcji...
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Analiza pola magnetycznego obiektów ferromagnetycznych
PublikacjaObiekt o właściowściach ferromagnetycznych zaburza równomierność pola magnetycznego Ziemi. mierząc indukcję magnetyczną precyzynjym magnetometrem można taki obiekt wykryć, zlokalizować i zidentyfikować. W algorytmach wykrywania obiektów ferromagnetycznych stosuje się model pola magnetycznego w postaci dipola magnetycznego. Modelowanie pola magnetycznego obiektu za pomocą dipola magnetycznego jest poprawne dla stosunkowo dużej odległości...
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HYDROACOUSTIC NOISE MEASUREMENTS
PublikacjaThe paper deals mainly with investigation of underwater noise that propagation is in shallow water. In this paper has been presented the experimental investigation results concerning the distribution of the sound field pressure generated by moving ships in the shallow water at the small distance from the ship. The main acoustical characteristics describing features of the field are spectrograms in pseudo 3D system – distance and frequency...
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Image Processing Techniques for Distributed Grid Applications
PublikacjaParallel approaches to 2D and 3D convolution processing of series of images have been presented. A distributed, practically oriented, 2D spatial convolution scheme has been elaborated and extended into the temporal domain. Complexity of the scheme has been determined and analysed with respect to coefficients in convolution kernels. Possibilities of parallelisation of the convolution operations have been analysed and the results...
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Zastosowanie AutoCAD Civil3D w nauczaniu projektowania dróg szynowych
PublikacjaNa Wydziale Inźynierii Lądowej i Środowiska Politechniki Gdańskiej od kilku lat głównym programem typu CAD wykorzystywanym w procesie kształcenia jest AutoCAD Civil 3D. Wersja edukacyjna tego programu jest zainstalowana w uczelnianych laboratoriach komputerowych, a studenci i pracownicy uczelni mogą go instalować na swoich komputerach w ramach programu Autodesk Student Engineering & Design Community. Jednak sposób rozwiązywania...
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Measurements and Simulations of Engineered Ultrasound Loudspeakers
PublikacjaSimulation and measurement results of the sound emitted from an ultrasound custom-made system with high spatial directivity are presented. The proposed system is using modulated ultrasound waves which demodulate in nonlinear medium resulting in audible sound. The system is aimed at enhancing the users’ personal audio space, therefore the measurements are performed using the Head and Torso Simulator which provides realistic reproduction...
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Tryton Supercomputer Capabilities for Analysis of Massive Data Streams
PublikacjaThe recently deployed supercomputer Tryton, located in the Academic Computer Center of Gdansk University of Technology, provides great means for massive parallel processing. Moreover, the status of the Center as one of the main network nodes in the PIONIER network enables the fast and reliable transfer of data produced by miscellaneous devices scattered in the area of the whole country. The typical examples of such data are streams...
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Seafloor relief reconstruction from side scan sonar data
PublikacjaSide scan sonar is one of the most widely used imaging systems in the underwater environment. It is relatively cheap and easy to deploy, in comparison with more powerful sensors. Although side scan sonar does not provide seafloor bathymetry directly, its records are directly related to seafloor images. In the paper, the method for 3D seafloor relief reconstruction from side scan sonar data is presented. The method is based on the...
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Wykorzystanie oprogramowania GeoGebra do wizualizacji w nauczaniu matematyki
PublikacjaW artykule zaprezentowano przykładowe aplety, które zostały przygotowane przez autorów w programie GeoGebra. Część z nich wykorzystano do stworzenia kursu elearningowego Liczby zespolone, używanego na Politechnice Gdańskiej. Inne użyto jako materiały pomocnicze w czasie tradycyjnych zajęć kursowych z matematyki dla pierwszego roku studiów, oraz podczas kursów: przygotowawczego z matematyki do matury i do studiów. Szczególną...
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Comparative characterisation of durian, mango and avocado
PublikacjaCelem przeprowadzonych badan była ocena właściwości odżywczych i bioaktywnych stosunkowo mało znanych egzotycznych owoców duriana i ich porównanie z parametrami charakteryzującymi powszechnie znane owoce mango i gruszki adwokackiej. W badaniach wykorzystano takie techniki jak HPLC, trójwymiarowa fluorescencja (3D-FL), testy oparte na zastosowaniu rodników (ABTS i DPPH) oraz zaawansowane techniki chemometryczne. na podstawie uzyskanych...
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Nowa metoda wyznaczenia pola powierzchni skóry przedramienia i dłoni wykorzystująca sztuczną sieć neuronową
PublikacjaW artykule przedstawiono rozbieżności pomiędzy wartościami pola powierzchni skóry obliczonymi za pomocą znanych metod a ich rzeczywistymi wartościami. Wykorzystując skaner 3D o wysokiej dokładności, zmierzono pole powierzchni skóry przedramienia i dłoni. Zaobserwowano, że błędy obliczeń są w wysokim stopniu skorelowane z wartościami BMI badanych osób. W grupie osób o BMI poniżej 20 stwierdzono maksymalny błąd względny wynoszący...
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RSS-Based DoA Estimation in 802.11p Frequency Band Using ESPAR Antenna and PPCC-MCP Method
PublikacjaIn this paper, the concept of direction of arrival (DoA) estimation using electronically steerable parasitic array radiator (ESPAR) antenna designed to operate in IEEE 802.11p vehicular communication standard has been investigated with respect to different possible elevation angles of a radio frequency (RF) signal impinging the antenna. To this end, two different possible sets of the 3D antenna radiation patterns have been used...
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MULTI-CRITERIA COMPARATIVE ANALYSIS OF THE USE OF SUBTRACTIVE AND ADDITIVE TECHNOLOGIES IN THE MANUFACTURING OF OFFSHORE MACHINERY COMPONENTS
PublikacjaThe dynamic development of additive manufacturing technologies, especially over the last few years, has increased the range of possible industrial applications of 3D printed elements. This is a consequence of the distinct advantages of additive techniques, which include the possibility of improving the mechanical strength of products and shortening lead times. Offshore industry is one of these promising areas for the application...
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Immersive Technologies that Aid Additive Manufacturing Processes in CBRN Defence Industry
PublikacjaTesting unique devices or their counterparts for CBRN (C-chemical, B-biological, R-radiological, N-nuclear) defense relies on additive manufacturing processes. Immersive technologies aid additive manufacturing. Their use not only helps understand the manufacturing processes, but also improves the design and quality of the products. This article aims to propose an approach to testing CBRN reconnaissance hand-held products developed...
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A new approach of coastal cliff monitoring using Mobile Laser Scanning
PublikacjaThe article proposes a new approach of coastal cliff monitoring which bases on a new comprehensive monitoring system, being a combination of mobile scanning from the sea with the geotechnical stability analysis. Mobile laser scanning is an innovative solution for 3D data collection which allows the monitored object geometry to be precisely measured, thus providing opportunities for series of analyses contributing to the development...
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Computational Fluid Dynamics Simulation of Gas–Liquid Multiphase Flow in T-junction for CO2 Separation
PublikacjaThe article presents the results of a computational fluid dynamics (CFD) analysis of gas-liquid multiphase flow. The simulation was conducted using CFD code and the Euler–Euler approach. The presented study relates to the non–reactive, steady-state, turbulent flow of water and carbon dioxide mixture in a 3D pipe. Separation phenomenon between phases is observed. The solution was obtained using a mixture model. Different values...
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Diatoms Biomass as a Joint Source of Biosilica and Carbon for Lithium-Ion Battery Anodes
PublikacjaThe biomass of one type cultivated diatoms (Pseudostaurosira trainorii), being a source of 3D-stuctured biosilica and organic matter—the source of carbon, was thermally processed to become an electroactive material in a potential range adequate to become an anode in lithium ion batteries. Carbonized material was characterized by means of selected solid-state physics techniques (XRD, Raman, TGA). It was shown that the pyrolysis...
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Experimental investigations of damage evolution in concrete during bending by continuous micro-CT scanning
PublikacjaThe paper describes experimental investigation results of fracture in notched concrete beams under quasi-static three-point bending. To visualize 3D fracture in concrete under bending, an extended X-ray micro-computed tomography system was used, i.e. the tomography system SkyScan 1173 was connected to the loading machine ISTRON 5569. This combined system enabled to shot images of deforming concrete beams during a continuous deformation...
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Investigations on fracture in reinforced concrete beams in 3-point bending using continuous micro-CT scanning
PublikacjaThis study explores a fracture process in rectangular reinforced concrete (RC) beams subjected to quasi-static three-point bending. RC beams were short and long with included longitudinal reinforcement in the form of a steel or basalt bar. The ratio of the shear span to the effective depth was 1.5 and 0.75. The focus was on the load–deflection diagram and crack formation. Three-dimensional (3D) analyses of the size and distribution...
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The lanthanide influence on selected properties of BaLnCo2O6-δ
PublikacjaThe subject of research of this dissertation are cobalt oxides with a double perovskite structure with a general formula BaLnCo2O6-δ, where Ln stands for La, Pr, Nd, Sm, Gd, Tb, Dy. The aim of the study was to verify the ability of these materials to form the protonic defects, as well as to identify the factors determining this ability. As part of the work, materials from the proposed group were synthesised and characterized. To...
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Formation and Growth of the Crack in Bonded Joints Under Mode I Fracture: Substrate Deflection at Crack Vicinity
PublikacjaAdhesive bonding is now commonly used in aircraft, cars, boats, etc. In these applications, thin panels are often bonded. In such thin structures, heterogeneous mechanical loading along the bondline edge (or potential crack front), is likely to arise due to 3D structural effects. The crack front and its vicinity is a special region, in that it is where structural properties of the adherend material meet those of the adhesive (discontinuity)....
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Simplified stability analysis of steel cylindrical silos with corrugated walls and vertical columns
PublikacjaIn the paper a simplified stability analysis of steel cylindrical silos composed of corru¬gated walls and vertical open-sectional columns was proposed. The whole 3D silo was modeled as a single column resting on elastic foundation provided by the silo walls. In proposed formula for the calculation of the foundation stiffness the curvature of the silo walls was taken into account. Three different analyses were carried out using...
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Benzene-induced hydro(solvo)thermal synthesis of Cu2+ and Zn2+ coordination polymers based on 1,3-benzenedicarboxylate
PublikacjaHydro(solvo)thermal reactions of Cu(NO3)2·2.5H2O or Zn(NO3)2·6H2O with 1,3-H2bdc provided two structurally different coordination polymers; a 2D network “metallacalixarene” based on the paddlewheel-type cluster with the formula [Cu(1,3-bdc)·H2O]·H2O (1) and a 3D framework [Zn(1,3-bdc)] (2), respectively. The use of a base was unnecessary in this synthesis; however, the presence of benzene played a crucial role in the crystallization...
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Face Profile View Retrieval Using Time of Flight Camera Image Analysis
PublikacjaMethod for profile view retrieving of the human face is presented. The depth data from the 3D camera is taken as an input. The preprocessing is, besides of standard filtration, extended by the process of filling of the holes which are present in depth data. The keypoints, defined as the nose tip and the chin are detected in user’s face and tracked. The Kalman filtering is applied to smooth the coordinates of those points which...
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Wpływ kształtu otwartego obiektu ferromagnetycznego na pole magnetyczne.Influence of shape of open ferromagnetic object on magnetic field.
PublikacjaObiekt o właściwościach ferromagnetycznych znajdujący się w ziemskim polu magnetycznym zaburza równomierność tego pola. Przestrzenny rozkład zaburzenia pola zależy od wielu czynników, w tym między innymi od rozmiarów i kształtu obiektu, od jego właściwości ferro-magnetycznych i od położenia względem wektora ziemskiego pola magnetycznego. Na podstawie pomiaru rozkładu pola magnetycznego wokół obiektu można dokonać lokalizacji i...
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Design of a test bench for determining the general characteristics of an internal combustion engine using a hydraulic power take-off system
PublikacjaThe paper presents a design of an engine test bench, which is used to determine the general characteristics of a truck engine using a power take-off (PTO). PTO drives a hydraulic system that generates a load on the engine at various points in its operation in the power range specified by the hydraulic system. The design allows for stationary and mobile tests with the test bench mounted on the truck, without any modification of...
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Structural and Material Determinants Influencing the Behavior of Porous Ti and Its Alloys Made by Additive Manufacturing Techniques for Biomedical Applications
PublikacjaOne of the biggest challenges in tissue engineering is the manufacturing of porous structures that are customized in size and shape and that mimic natural bone structure. Additive manufacturing is known as a sufficient method to produce 3D porous structures used as bone substitutes in large segmental bone defects. The literature indicates that the mechanical and biological properties of scaffolds highly depend on geometrical features...
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OPTIMIZATION OF THE LAST STAGE OF GAS-STEAM TURBINE USING A HYBRID METHOD
PublikacjaThis paper relates to the CFD calculation of a new turbine type which is in the phase of theoretical analysis, because the working fluid is a mixture of steam and gas generated in wet combustion chamber. At first, this article concentrates on a possibility of streamlining the flow efficiency of a last stage of axial turbine working on gas-steam mixture using a hybrid of the particle swarm optimization algorithm with the Nelder-Mead...
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Recent advances in compatibilization strategies of wood-polymer composites by isocyanates
PublikacjaWood-polymer composites technologies are gaining more and more attention in the scientific community, positively affecting the increase in their industrial applications, for example, automotive, building, 3D printing, etc. Many research works are focused on the improvement in matrix–lignocellulosic filler interactions to produce highly filled composites with satisfying performance properties. In this field of research, using isocyanates...
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Microfluidic devices for photo-and spectroelectrochemical applications
PublikacjaThe review presents recent developments in electrochemical devices for photo- and spectroelectrochemical investigations, with the emphasis on miniaturization (i.e., nanointerdigitated complementary metal-oxide-semiconductor devices, micro- and nano-porous silicon membranes or microoptoelectromechanical systems), silica glass/microreactors (i.e., plasmonic, Raman spectroscopy or optical microcavities) or polymer-based devices (i.e.,...
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Structural response of existing spatial truss roof construction based on Cosserat rod theory
PublikacjaPaper presents the application of the Cosserat rod theory and newly developed associated finite elements code as the tools that support in the expert-designing engineering practice. Mechanical principles of the 3D spatially curved rods, dynamics (statics) laws, principle of virtual work are discussed. Corresponding FEM approach with interpolation and accumulation techniques of state variables are shown that enable the formulation...
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Analysis of luminance distribution uniformity in CAVE-type virtual reality systems
PublikacjaIn recent years, many scientific and industrial centers in the world developed a virtual reality systems or laboratories. The effect of user “immersion” into virtual reality in such systems is largely dependent of optical properties of the system. In this paper, problems of luminance distribution uniformity in CAVE-type virtual reality systems are analyzed. For better characterization of CAVE luminance nonuniformity corner and...
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Classification of objects in the LIDAR point clouds using Deep Neural Networks based on the PointNet model
PublikacjaThis work attempts to meet the challenges associated with the classification of LIDAR point clouds by means of deep learning. In addition to achieving high accuracy, the designed system should allow the classification of point clouds covering an area of several dozen square kilometers within a reasonable time interval. Therefore, it must be characterized by fast processing and efficient use of memory. Thus, the most popular approaches...
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Wybrane aspekty modelowania matematycznego kolejowego odbieraka prądu
PublikacjaNieprawidłowa współpraca odbieraka z siecią jezdną, w niekorzystnych warunkach lokalnych, prowadzi do uszkodzeń sieci lub odbieraka. Może być to spowodowane niewłaściwym wykonaniem lub utrzymaniem tych istotnych elementów układu zasilania. Tego typu sytuacje awaryjne powodują duże opóźnienia w ruchu pociągów i generują olbrzymie koszty. Wskazuje to na duże znaczenie odpowiednich rozwiązań konstrukcyjnych sieci i odbieraków oraz...
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Wsparcie rzeczywistości wirtualnej dla projektów realizowanych w ASP w Gdańsku / Virtual reality support for the projects carried out in the AFA in Gdańsk
PublikacjaLaboratorium Zanurzonej Wizualizacji Przestrzennej (LZWP) jest unikatowym w skali kraju miejscem, gdzie w grupie kilku osób można wspólnie eksplorować świat iluzji. Na takie doświadczenie pozwalają znajdujące się tam jaskinie rzeczywistości wirtualnej (ang. Cave Automatic Virtual Environment, CAVE) umożliwiające uczestnikom eksperymentu wniknięcie w środowisko zarówno kreowane komputerowo, jak i stanowiące cyfrową kopię realnego...
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Research of leakage magnetic field in deenergized transformer
PublikacjaThe article deals with the issue of the numerical analysis of the magnetic field occurring around the transformer after it has been powered down. The main goal of this analysis was to examine if it is possible to identify the residual fluxes in the transformer legs based on this fields’ measurements. It was also intended to determine the type and the location of magnetic sensors. Numerical analysis of the magnetic field was performed....
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Camera Orientation-Independent Parking Events Detection
PublikacjaThe paper describes the method for detecting precise position and time of vehicles parking in a parking lot. This task is trivial in case of favorable camera orientation but gets much more complex when an angle between the camera viewing axis and the ground is small. The method utilizes background subtraction and object tracking algorithms for detecting moving objects in a video stream. Objects are classified into vehicles and...
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Preparation and X-ray structures of selected aminium thiosulfates
PublikacjaVarious types of aminium thiosulfates (1–6), including hydrates and mixed salts, have been obtained by the reaction of ammonium thiosulfate with amines. Tertbutylamine, cyclo-hexylamine and 1,6-diaminohexane gave crystals of (t-BuNH3)2S2O3·H2O (1), (c-C6H11NH3)2S2O3 (3) and {(NH4)2(H3NC6H12NH3)(S2O3)2} (6), respectively, which were investigated by X-ray structural analysis. Extensive hydrogen bonding of the N-H…O and N-H…S type...
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Buckling Analysis of Cold Formed Silo Column
PublikacjaThe paper is devoted to stability analysis of different models of steel cold formed silo column. The steel cylindrical silos are often composed of corrugated walls and vertical open-sectional columns uniformly placed along the silo circumference. Both the whole 3D silo, a simplified model consisting of one column with a part of the silo walls, and a single column resting on elastic foundation provided by the silo walls were analyzed....
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Analysis of the applicability of laser scanning to making an inventory of swimming pool facilities
Publikacja3D scanning can be used in many branches of economy, e.g. reverse and prototype engineering, industrial design, quality control, pros-thetics, orthodontics, archiving of historic objects and archeological findings, examination of a scene of crime, making films and comput-er games. The technology of terrestrial laser scanning has a bright fu-ture as we are living in the time of blooming measurement tech-niques, which can provide...
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Multibeam sonar data processing for seafloor characterisation
PublikacjaThe approach to seafloor characterisation was investigated. It relies on calculation of several descriptors (parameters) related to seabed type using three types of multibeam sonar data obtained during seafloor sensing: 1) the grey-level sonar images of seabed, 2) the 3D model of the seabed surface which consist of (x, y, z) points, 3) the set of time domain echo envelopes corresponding to several beams. The proposed method has...
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Combined method of multibeam sonar signal processing and image analysis for seafloor classification
PublikacjaThe combined approach to seafloor characterisation was investigated. It relies on calculation of several descriptors (parameters) related to seabed type using three types of multibeam sonar data obtained during seafloor sensing: 1) the grey-level sonar images (echograms) of seabed, 2) the 3D model of the seabed surface which consists of bathymetric data, 3) the set of time domain bottom echo envelopes received in the consecutive...