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Wyniki wyszukiwania dla: LEAST SQUARE METHOD, CONDITIONAL EQUATIONS METHOD, TRAMWAY TRACK, GDANSK AGGLOMERATION, MATHCAD, RAIL VEHICLE TRAJECTORY, GLOBAL POSITIONING SYSTEM (GPS), SATNAV RECEIVER
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A Novel Method for the Deblurring of Photogrammetric Images Using Conditional Generative Adversarial Networks
PublikacjaThe visual data acquisition from small unmanned aerial vehicles (UAVs) may encounter a situation in which blur appears on the images. Image blurring caused by camera motion during exposure significantly impacts the images interpretation quality and consequently the quality of photogrammetric products. On blurred images, it is difficult to visually locate ground control points, and the number of identified feature points decreases...
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Precise Point Positioning Method Based on Wide-lane and Narrow-lane Phase Observations and Between Satellites Single Differencing
PublikacjaThe issue of using PPP method in position determination was formed in 1997. In most developed methods, ionospheric-free linear combination is used in order to eliminate the impact of the ionospheric delay. However, this approach does not provide the directly determination of the total value of the ambiguities, and the ambiguities for the individual signals. Therefore, in many publications methods of avoiding these deficiencies...
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Matching trajectory of a person to a map in inertial navigation system
PublikacjaPaper describes the method of matching, to a map, trajectories of a person walking indoors, obtained from inertial navigation module. General principle of matching algorithm based on particle filtering is presented. Method of detecting particle collisions is described as well. The last chapter provides test results of map matching related to a true trajectory.
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Estimation and Prediction of Vertical Deformations of Random Surfaces, Applying the Total Least Squares Collocation Method
PublikacjaThis paper proposes a method for determining the vertical deformations treated as random fields. It is assumed that the monitored surfaces are subject not only to deterministic deformations, but also to random fluctuations. Furthermore, the existence of random noise coming from surface’s vibrations is also assumed. Such noise disturbs the deformation’s functional models. Surface monitoring with the use of the geodetic levelling...
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Evaluation of the fast impedance spectroscopy method in the laboratory measurement system
PublikacjaIn this paper the method for fast impedancespectroscopy of technical objects with very high impedance(|Zx| ≥ 1 GΩ) is evaluated by means of simulation and practicalexperiment. The method is based on excitation of an object, witha square pulse and measurements of voltage and currentresponses with DAQ card. The object impedance spectrum isobtained with use of continuous Fourier transform. Someimprovements of the method concerned...
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BTEX concentration levels in urban air in the area of the Tri-City agglomeration (Gdansk, Gdynia, Sopot), Poland
PublikacjaThe paper presents and discusses the results of atmospheric air quality research conducted in 2012 with reference to the level of BTEX compounds in the Tri-City agglomeration—Gdansk, Gdynia, and Sopot (northern Poland). At the stage of BTEX sampling from the ambient air, Radiello® diffusive passive samplers were applied. The annual time-weighted average concentrations for benzene, toluene, ethylbenzene, and xylenes (BTEX) in the...
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Method of estimating the rolling resistance coefficient of vehicle tyre using the roller dynamometer
PublikacjaThe tendency in the past few years has been to introduce tyres with lower rolling resistance coefficients to the market. This paper presents a mathematical method for determining the rolling resistance coefficients variation depending on the speed. The method uses power balance which results from automobile dynamics while rolling on chassis dynamometer. The rolling resistance coefficients of tyres obtained through ‘drum test method’,...
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The modelling method of discrete-continuous systems
PublikacjaThe paper introduces a method of discrete-continuous systems modelling. In the proposed method a three-dimensional system is divided into finite elements in only two directions, with the third direction remaining continuous. The thus obtained discrete-continuous model is described by a set of partial differential equations. General difference equations of discrete system are obtained using the rigid finite element method. The limit...
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System wykrywania i przeciwdziałania spoofingowi GPS
PublikacjaSpoofing w systemach nawigacji satelitarnej jest atakiem elektronicznym, który polega na nieuprawnionej emisji sygnałów stanowiących imitacje rzeczywistych sygnałów odbieranych z satelitów. Powoduje on wyznaczenie nieprawidłowych informacji o czasie, położeniu i prędkości odbiornika. Z uwagi na trudność jego wykrycia, spoofing stanowi poważniejsze zagrożenie niż proste zagłuszanie sygnałów zakłóceniem o dużej mocy (ang. jamming)....
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Accuracy Of The GPS Positioning System In The Context Of Increasing The Number Of Satellites In The Constellation
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Receiver-side fingerprinting method for color images based on a series of quaternion rotations
PublikacjaThe proposed method is a new Joint Fingerprinting and Decryption (JFD) method that uses a cipher based on quaternion rotation to encrypt color images that are then sent to all users via multicast transmission. Individual encryption keys depend on the users’ fingerprints, so that a unique fingerprint is introduced into the image during decryption for each decryption key. A simulation-based research was conducted to examine the method’s...
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Assessment of the Steering Precision of a Hydrographic Unmanned Surface Vessel (USV) along Sounding Profiles Using a Low-Cost Multi-Global Navigation Satellite System (GNSS) Receiver Supported Autopilot
Publikacjahe performance of bathymetric measurements by traditional methods (using manned vessels) in ultra-shallow waters, i.e., lakes, rivers, and sea beaches with a depth of less than 1 m, is often difficult or, in many cases, impossible due to problems related to safe vessel maneuvering. For this reason, the use of shallow draft hydrographic Unmanned Surface Vessels (USV) appears to provide a promising alternative method for performing...
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Design of dimensionally stable composites using efficient global optimization method
PublikacjaDimensionally stable material design is an important issue for space structures such as space laser communication systems, telescopes, and satellites. Suitably designed composite materials for this purpose can meet the functional and structural requirements. In this paper, it is aimed to design the dimensionally stable laminated composites by using efficient global optimization method. For this purpose, the composite plate optimization...
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Adaptive dynamic control allocation for dynamic positioning of marine vessel based on backstepping method and sequential quadratic programming
PublikacjaIt is generally assumed in dynamic positioning of over-actuated marine vessels that the control effectiveness matrix (input matrix) is known and constant, or, in case of fault information, it is estimated by the fault detection and diagnosis system. The purpose of the study is to develop the adaptive dynamic positioning control system for an over-actuated marine vessel in the presence of uncertainties and with emphasis on limited...
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ADAPTIVE METHOD FOR THE SOLUTION OF 1D AND 2D ADVECTION-DIFFUSION EQUATIONS USED IN ENVIRONMENTAL ENGINEERING
PublikacjaThe paper concerns the numerical solution of one-dimensional (1D) and two-dimensional (2D) advection-diffusion equations. For the numerical solution of the 1D advection-diffusion equation a method, originally proposed for solution of the 1D pure advection equation, has been developed. A modified equation analysis carried out for the proposed method allowed increasing of the resulting solution accuracy and consequently, to reduce...
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The method of measuring the energy pass-band of a communication receiver
PublikacjaPrzedstawiono metodę wyznaczania energetycznego pasma odbiornika radiokomunikacyjnego na podstawie charakterystyki gęstości widmowej mocy szumów własnych na wyjściu odbiornika. Podano numeryczny estymator tego pasma. Wyprowadzono zależności na złożoną niepewność standardową wyznaczania szerokości pasma energetycznego odbiornika.
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The construction of suspended rail vehicle bogie
PublikacjaNiniejsza publikacja została poświęcona szczegółowemu opisowi wózka, przeznaczonego do wykorzystania w proponowanej przez autorów koncepcji podwieszanego pojazdu szynowego. W pierwszej kolejności skrótowo opisano rzeczony pojazd, ze szczególnym naciskiem na parametry determinujące konstrukcję wózków. Następnie zostały omówione zastosowane rozwiązania konstrukcyjne w zakresie budowy poszczególnych podzespołów wózka, takich jak: zestawy...
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The concept of suspended urban rail vehicle
PublikacjaNiniejsza publikacja została poświęcona szczegółowemu opisowi proponowanej przez autorów koncepcji podwieszanego pojazdu szynowego. W pierwszej kolejności przeanalizowano istniejące rozwiązania, wraz ze wskazaniem ich podstawowych wad i zalet. Następnie opisano proponowaną konstrukcję w zakresie: budowy wagonu, sposobu jego zawieszenia oraz prowadzenia po zadanym torze ruchu. Artykuł ten powstał na podstawie pracy dyplomowej pt....
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The Positioning Accuracy of BAUV Using Fusion of Data from USBL System and Movement Parameters Measurements
PublikacjaThe article presents a study of the accuracy of estimating the position coordinates of BAUV (Biomimetic Autonomous Underwater Vehicle) by the extended Kalman filter (EKF) method. The fusion of movement parameters measurements and position coordinates fixes was applied. The movement parameters measurements are carried out by on-board navigation devices, while the position coordinates fixes are done by the USBL (Ultra Short Base...
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Development of Local IDF-formula Using Controlled Random Search Method for Global Optimization
PublikacjaThe aim of the study is to present the effective and relatively simple empirical approach to rainfall Intensity-Duration-Frequency-formulas development, based on Controlled Random Search (CRS) for global optimization. The approach is mainly dedicated to the cases in which the commonly used IDF-relationships do not provide satisfactory fit between simulations and observations, and more complex formulas with higher number of parameters...
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Analytical method of modelling the geometric system of communication route
PublikacjaThe paper presents a new analytical approach to modelling the curvature of a communication route by making use of differential equations. The method makes it possible to identify both linear and nonlinear curvature. It enables us to join curves of the same or opposite signs of curvature. Solutions of problems for linear change of curvature and selected variants of nonlinear curvature in polynomial and trigonometric form were analyzed....
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Study on the Positioning Accuracy of the GNSS/INS System Supported by the RTK Receiver for Railway Measurements
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Integration of inertial sensors and GPS system data for the personal navigation in urban area
PublikacjaGPS and Inertial Navigation Systems (INS) have complementary properties and they are therefore well suited for integration. The integrated solution offers better long-term accuracy than a stand-alone INS and better integrity, availability and continuity or a stand-alone GPS receiver, making it suitable for demanding applications. The complementary features of INS and GPS are the main reasons why integrated GPS/INS systems are becoming...
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Atypical application of the parametric method for track infrastructure inventory
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Framework of an Evolutionary Multi-Objective Optimisation Method for Planning a Safe Trajectory for a Marine Autonomous Surface Ship
PublikacjaThis paper represents the first stage of research into a multi-objective method of planning safe trajectories for marine autonomous surface ships (MASSs) involved in encounter situations. Our method applies an evolutionary multi-objective optimisation (EMO) approach to pursue three objectives: minimisation of the risk of collision, minimisation of fuel consumption due to collision avoidance manoeuvres, and minimisation of the extra...
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Results of the application of tropospheric corrections from different troposphere models for precise GPS rapid static positioning
PublikacjaIn many surveying applications, determination of accurate heights is of significant interest. The delay caused by the neutral atmosphere is one of the main factors limiting the accuracy of GPS positioning and affecting mainly the height coordinate component rather than horizontal ones. Estimation of the zenith total delay is a commonly used technique for accounting for the tropospheric delay in static positioning. However, in the...
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Analytical design method of reverse curves
PublikacjaThe paper deals with a new approach relating to the design of the region of railway track direction alteration adapted to Mobile Satellite Measurements technique. The method may be particularly useful in situations when both the straights of the route directions cannot be connected in an elementary way using a circular arc with transition curves; this also refers to the application of a compound curve. Thus the only solution becomes...
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Evaluation of suspended rail vehicle movement parameters
PublikacjaNiniejsza publikacja została poświęcona ocenie parametrów ruchowych koncepcyjnego pojazdu kolei podwieszanej, którą dokonano w oparciu o jego charakterystykę trakcyjną oraz możliwości dynamiczne. W pierwszej kolejności skrótowo opisano konstrukcję proponowanego pojazdu wraz z wyszczególnieniem najważniejszych założeń projektowych. Następnie skupiono się na metodyce oraz samym wykreśleniu charakterystyki trakcyjnej pojazdu, jak...
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Stress analysis of suspended rail vehicle bogie
PublikacjaNiniejsza publikacja została poświęcona analizie wytrzymałościowej wybranych elementów wózka – osi zestawu kołowego i ramy. Obliczenia osi wykonano w oparciu o metodę analityczną przy rozpatrzeniu różnych materiałów jej wykonania. Do sprawdzenia wytrzymałości ramy wykorzystano metodę elementów skończonych, a obciążenie wyznaczono zgodnie z wytycznymi normy PN-EN 13749. Sam wózek jest częścią podwieszanego elektrycznego zespołu...
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Development of the urban rail vehicle acoustic model
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Phase-difference positioning in asynchronous system
PublikacjaThis paper presents concept and implementation of digital positioning system based on phase difference measurements, designed as a navigational aid for marine applications. Main feature of proposed system is the ability to work in both synchronous mode, with one master station and set of slave stations synchronized with master, and in asynchronous mode with independent clocking of all stations.
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Design of rail-track geometric systems by satellite measurement
PublikacjaW pracy przedstawiono rezultaty zastosowania ciągłych pomiarów satelitarnych toru kolejowego, z antenami zainstalowanymi na poruszającym się pojeździe szynowym. Wykazano, że zastosowana pilotażowo technika pomiarowa umożliwia bardzo precyzyjne określenie podstawowych danych do projektowania modernizacji linii kolejowej (kierunków głównych trasy i jej kąta zwrotu), a także - ze stosunkowo niewielkim błędem - współrzędnych istniejącej...
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Sensors and System for Vehicle Navigation
PublikacjaIn recent years, vehicle navigation, in particular autonomous navigation, has been at the center of several major developments, both in civilian and defense applications. New technologies, such as multisensory data fusion, big data processing, or deep learning, are changing the quality of areas of applications, improving the sensors and systems used. Recently, the influence of artificial intelligence on sensor data processing and...
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Remarks on the convergence of an iterative method of solution of generalized least squares problem
PublikacjaW pracy przedstawiona jest metoda iteracyjna znajdowania regularyzowanego (w sensie Tichonowa) rozwiązania układu równań Ax=b z dowolną macierzą A. Dla danej liczby alfa i wektora g daje ona ciąg przybliżeń zbieżny do rozwiązania (w sensie najmniejszych kwadratów) tego układu. Rozwiązanie to minimalizuje odległość zbioru wszystkich rozwiązań średniokwadratowych układu Ax=b od wektora g. Podane zostało również oszacowanie szybkości...
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Determination of rectification corrections for semi gantry crane rail axes in the local 3D coordinate system
PublikacjaElectronic tacheometers are currently the standard instruments used in geodetic work, including also geodetic engineering measurements. The main advantage connected with this equipment is among others high accuracy of the measurement and thus high accuracy of the final determinations represented for example by the points’ coordinates. One of many applications of the tacheometers is the measurement of crane rail axes. This measurement...
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Hyperbolic Asynchronous Method of a Radio Navigation Technique
PublikacjaHumans have always wanted to determine position in an unknown environment. At the beginning methods were simple. They were based on the observation of characteristic points, in the case of shipping additional observations of the coastline. Then came navigation based on astronomical methods (astronavigation). At the beginning of the XX-century a new way of determining the current location was developed. It has used radiowave signals....
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Tracking body movement for radio channel measurements in BAN with indoor positioning system
PublikacjaThis paper presents indoor positioning system based on inertial navigation with additional distance measurements using UWB modems and map matching to increase accuracy and eliminate position drift. Such system may be used to track position of human body during radio channel measurements for body area networks. Performance of proposed system and limitations caused by inertial navigation are briefly described.
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Propulsion System Analysis Based on Particle Image Velocimetry Method in Biomimetic Unmanned Underwater Vehicle
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Successive Iterative Method for Higher-Order Fractional Differential Equations Involving Stieltjes Integral Boundary Conditions
PublikacjaIn this paper, the existence of positive solutions to fractional differential equations with delayed arguments and Stieltjes integral boundary conditions is discussed. The convergence of successive iterative method of solving such problems is investigated. This allows us to improve some recent works. Some numerical examples illustrate the results.
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Precise method of vehicle velocity determination basing on measurements of car body deformation–non-linear method for ‘Full Size’ vehicle class
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Analysis of Accuracy of Modified Gradient Method in Indoor Radiolocalisation System
PublikacjaIn this paper a new method, called modified gradient method, has been proposed for position calculation on the basis of distance measurement in indoor environment. It is shown that well known method of position calculation such as Foy is inefficient in indoor environment. In this article is also described the indoor radiolocalisation system which was used for collecting distance measurements which were employed for further comparative...
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Preconditioners with Low Memory Requirements for Higher-Order Finite-Element Method Applied to Solving Maxwell’s Equations on Multicore CPUs and GPUs
PublikacjaThis paper discusses two fast implementations of the conjugate gradient iterative method using a hierarchical multilevel preconditioner to solve the complex-valued, sparse systems obtained using the higher order finite-element method applied to the solution of the time-harmonic Maxwell equations. In the first implementation, denoted PCG-V, a classical V-cycle is applied and the system of equations on the lowest level is solved...
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Transmission system model in the track-vehicle relationship based on Long Term Evolution technology
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Evaluation of the reference fuel consumption and CO2 emission of vehicle with using of the map of operating conditions for selected agglomeration
PublikacjaZaproponowana w pracy metoda tworzenia mapy warunków eksploatacji dla wybranej aglomeracji może zostać przeprowadzona przy wykorzystaniu tanich i prostych w obsłudze urządzeń. Podstawowym urządzeniem badawczym jest pojazd samochodowy wyposażony w system pomiaru położenia GPS z układem korekty wskazań wysokości i rejestracji parametrów jazdy. Zamieszczony w pracy przykład wykorzystania mapy warunków eksploatacji pokazuje możliwości...
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Method using square-pulse excitation for high-impedance spectroscopy of anticorrosion coatings
PublikacjaArtykuł prezentuje metodę spektroskopii impedancyjnej przeznaczonej do diagnostyki powłok antykorozyjnych na obiektach bezpośrednio w terenie. Aby skrócić czas uzyskania widma impedancji (w zakresie od 1 mHz do 1 MHz) do kilku minut, wykorzystano sygnały harmoniczne do pomiaru widma powyżej 10 Hz a impuls prostokątny w dolnym zakresie częstotliwości. Do wyznaczania widma użyto algorytmów DSP odpowiednich do sygnału pobudzenia....
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Non-places in the centre of the historic Main Town in Gdansk? – Design Thinking as a method of solving problems in cities
PublikacjaThe interiors of reconstructed extensive blocks of the historic Main Town in Gdansk are nowadays degraded areas, full of cars, with “holes” after never-finished archaeological excavations. It is not surprising that inhabitants avoid them. These are NON-PLACES. This situation prompts social movements to act. The first step towards the change was the interdisciplinary and transdisciplinary project of revitalization of one of the...
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System setup and software for cyclic, staircase and square wave voltammetry measurements
PublikacjaHardware dedicated for electrochemical measurement sometimes does not allow performing certain voltammetry experiments. Staircase and square wave voltammetry, techniques which have many advantages comparing with standard voltammetric techniques, are rarely implemented in software controlling electrochemical measuring equipment. These methods, however, can be relatively easy realized with some addition...
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A new deterministic method of finding safe ship trajectory for any convex domain
PublikacjaW artykule wprowadzono nową deterministyczną metodę wyznaczania bezpiecznej trajektorii statku dla sytuacji spotkania z wieloma obiektami obcymi i dla dowolnej zadanej domeny. Jej prostota i fakt, że minimalizuje ona liczbę manewrów czynią ją dobrą alternatywą dla obecnie stosowanych metod. Metoda jest przedstawiona tak, aby mogła być bezpośrednio zastosowana w pokładowych systemach antykolizyjnych lub w systemach VTS.
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Simplified method of water cooled exhaust system design.
PublikacjaThe water cooled exhaust systems are not often used onboard ships. Prime goal is to lower temperature of exhaust gas from main propulsion and auxiliary engines to the defined limit. The design of such systems require detailed analysis of propulsion system operational parameters to meet designer expectations. The paper outlines the cooled exhaust system design problems in specific application. The simplified method of evaluation...
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Space-Time Conservation Method applied to numerical solution of water hammer equations
PublikacjaArtykuł poświęcony jest metodzie czasoprzestrzennych objętości skończonych (STC) zastosowanej do przypadku uderzenia hydraulicznego w stalowym przewodzie pracującym pod ciśnieniem. Metoda STC ze względu na swoje własności numeryczne - m.in. wysoką dokładność - może być interesującą alternatywą dla tradycyjnych metod numerycznych, szczególnie w przypadku, gdy efekty numeryczne mają bardzo silny wpływ na rozwiązanie, tym samym utrudniając...