Filtry
wszystkich: 2750
wybranych: 1987
-
Katalog
- Publikacje 1987 wyników po odfiltrowaniu
- Czasopisma 14 wyników po odfiltrowaniu
- Konferencje 2 wyników po odfiltrowaniu
- Osoby 36 wyników po odfiltrowaniu
- Projekty 2 wyników po odfiltrowaniu
- Laboratoria 1 wyników po odfiltrowaniu
- Kursy Online 147 wyników po odfiltrowaniu
- Wydarzenia 32 wyników po odfiltrowaniu
- Dane Badawcze 529 wyników po odfiltrowaniu
Filtry wybranego katalogu
wyświetlamy 1000 najlepszych wyników Pomoc
Wyniki wyszukiwania dla: railway line capacity
-
A new approach to determination of the two-mass model parameters of railway current collector
PublikacjaThe paper presents two mathematical models of railway current collectors both with two degrees of freedom. The first one, hereinafter Pantograph Articulated Model (PAM), has one degree of freedom in rotational motion and the second degree of freedom in translational motion. The second model, called henceforth as Pantograph Reference Model (PRM), has both degrees of freedom in translational motion. Differential equations of the...
-
Research project BRIK: development of an innovative method for determining the precise trajectory of a railway vehicle
PublikacjaIn the paper the essential assumptions regarding a research project implemented by a consortium of Gdansk University of Technology and Gdynia Maritime University are presented. The project has been commissioned by National Center of Research and Development with cooperation with Polish Railways (PKP Polskie Linie Kolejowe S.A.). The project is focused in implementation of modern measurement techniques using Global Navigation Positioning...
-
Wavelet transform-based approach to defect identification in railway carbon contact strips.
PublikacjaPantographs of electric rail vehicles are fitted with carbon contact strips, which slide along the contact wire of catenary to provide constant electrical contact. Contact strips are exposed to wear and damages. Using damaged contact strips significantly increases the risk of catenary rupture. Therefore, their technical condition has to be inspected frequently. In previous work a 3D laser scanning system was proposed for recording...
-
Optimization of Energetic Train Cooperation
PublikacjaIn the article, possible ways of using energy recovered during regenerative braking of trains are presented. It is pointed out that the return of recovered electricity directly to the catenary and its use in the energy cooperation of vehicles can be a no-cost method (without additional infrastructure). The method of energy cooperation between trains and its main assumptions, that uses the law of conservation of energy, are described...
-
Assessment of Subsoil Subsidence Under the Railway Surface with the Use of Fuzzy Sets
PublikacjaThe cause of the subsidence of the railway track is the subsidence of the track bed itself and it is often related to the subsidence of the subsoil. Such settlement leads to: uneven longitudinal railways and track twist. These phenomena have a negative impact on the comfort and safety of driving, and in extreme cases lead to a train derailment. It has been shown that the magnitude of these settlements is determined by many parameters...
-
Electrochemical investigations on corosivity of de-icing liquids for railway infrastructure
PublikacjaThe paper presents the results of electrochemical tests of the de-icing fluid for railway infrastructure. DC and AC electrochemical tests were performed to determine the corrosion rates of structural steel, cast iron and aluminium in the newly produced fluid. The results were compared with the corrosion rates of the same materials in the fluid without corrosion inhibitors. The obtained test results indicate a low corrosion risk...
-
Revitalization of the Narrow-Gauge Żuławy Commuter Railway and its effect on shipping conditions in the Vistula delta
PublikacjaThe article presents the Żuławy Access Railway and the effect of its revitalization on the change of navigational conditions in the Vistula delta. One of the problems analyzed in the article is the intersection of two different transport branches - the inland waterway and rail transport branches. A solution to the problem of their functioning is presented, without any major restrictions. Possible changes in navigational conditions...
-
Technical diagnostics and monitoring of traction current collectors
PublikacjaNew evaluation methods of the technical condition of rolling stock current collectors are proposed in this paper. The method of automatic measurement of the pantograph static force characteristic, realized when the vehicle runs through the test section of the track with especially prepared overhead line height distribution, has been practically implemented by the Polish Railways. The method of testing the slipper spring suspension...
-
Computer-aided evaluation of the railway track geometry on the basis of satellite measurements
PublikacjaIn recent years, all over the world there has been a period of intensive development of GNSS (Global Navigation Satellite Systems) measurement techniques and their extension for the purpose of their applications in the field of surveying and navigation. Moreover, in many countries a rising trend in the development of rail transportation systems has been noticed. In this paper, a method of railway track geometry assessment based...
-
Bypass kolejowy dla wiaduktu łukowego i kratownicowego w ciągu modernizowanej linii kolejowej E59 na odcinku Wronki – Dobiegniew
PublikacjaW artykule przedstawiono realizacje bypassu kolejowego, zlokalizowanego nieopodal miejscowości Krzyż Wielkopolski w ciągu linii kolejowej E59 na skrzyżowaniu z linią kolejową 203. Wariantowa analiza kilku zaproponowanych rozwiązań wykazała, ze wykonstruowanie bypassu na czas prowadzenia prac modernizacyjnych pozwoli na utrzymanie ciągłości ruchu kolejowego, nie stworzy nadmiernych problemów podróżnym, a jednocześnie pozwoli na...
-
Digital Filtering of Railway Track Coordinates in Mobile Multi–Receiver GNSS Measurements
PublikacjaThe article discusses an important issue in connection with the technique of mobile Global Navigation Satellite System (GNSS) measurements of railway track coordinates, which is digital filtering performed to precisely determine railway track axes. For this purpose, a measuring technique is proposed which bases on the use of a measuring platform with a number of appropriately distributed GNSS receivers, where two of them determine...
-
Optimizing the process of railway geometrical layout designing with multi-criteria assessment method
PublikacjaThe paper presents the main assumptions of the Multi-criteria assessment method used in process of upgrading the railway geometrical layout. The advantages of metaheuristic search were described. The criteria influencing the investment were defined. The fitness function used in the analysis was described. The example of using the optimization algorithm with the help of self developed computer software was described.
-
New Approach to Arc Fitting for Railway Track Realignment
PublikacjaThis article presents a new method of arc fitting for railway track realignment. The theoretical foundations are presented, along with a detailed algorithm of the iterative computational process. This method is based on solving a set of linearized pseudo-observation equations. The formulas of the functional model of the fitting problem were derived, and a special form of objective function is proposed. An iterative method for optimization...
-
Assessment of Adjustment of GNSS Railway Measurements with Parameter-Binding Conditions in a Stationary Scenario
PublikacjaThe study aims to assess the applicability of the ordinary least squares method, robust estimation, and conditions-binded adjustment in processing the six synchronous coordinate pairs of global navigation satellite system (GNSS) receivers. The research is part of the research project InnoSatTrack, focused on the enhancement of the determination of geometrical parameters of railway tracks using GNSS, inertial, and other sensors....
-
Installation of GNSS receivers on a mobile railway platform – methodology and measurement aspects
PublikacjaDetermining the course of a railway track axis using satellite methods relies on ensuring the precise assembly of GNSS receivers in dedicated measuring devices. Depending on the number of receivers, solutions that are based on placing the apparatus directly above the railway track axis (as well as in eccentric positions) are used to indirectly obtain data to form the basis of the desired results. This publication describes the...
-
Modelling of Curvature of the Railway Track Geometrical Layout Using Particle Swarm Optimization
PublikacjaA method of railway track geometrical layout design, based on application of cubic C-Bezier curves for describing the layout curvature is presented in the article. The control points of a cubic C-Bezier curve are obtained in an optimization process carried out using Particle Swarm Optimization algorithm. The optimization criteria are based on the evaluation of the dynamic interactions and satisfaction of geometrical design requirements.
-
Analysis of the Ways to Identify Rail Running Surface Defects by Means of Vibration Signals
PublikacjaTh e article discusses a preliminary concept of a method enabling the identifi cation of chosen rail running surface defects, such as squats, spalling, and running surface defects, by analysing the parameters of vibration signals. It features a description of the methodology of the conducted tests, the scope thereof, and the selection of the measurement points with specifi c defect types. Th e article covers selected results of...
-
Application of Least Squares with Conditional Equations Method for Railway Track Inventory Using GNSS Observations
PublikacjaSatellite geodetic networks are commonly used in surveying tasks, but they can also be used in mobile surveys. Mobile satellite surveys can be used for trackage inventory, diagnostics and design. The combination of modern technological solutions with the adaptation of research methods known in other fields of science offers an opportunity to acquire highly accurate solutions for railway track inventory. This article presents the...
-
Determining horizontal curvature of railway track axis in mobile satellite measurements
PublikacjaThe article discusses the applicability of a novel method to determine horizontal curvature of the railway track axis based on results of mobile satellite measurements. The method is based on inclination angle changes of a moving chord in the Cartesian coordinate system. In the presented case, the variant referred to as the method of two virtual chords is applied which consists in manoeuvring with only one GNSS (Global Navigation...
-
Multi-Option Model of Railway Traffic Organization Including the Energy Recuperation
PublikacjaThe article presents the issue of organization of railway traffic within the station, taking into account energy recuperation. We identified a number of factors which affect the energy efficiency of recuperation, including the issue of transfer of energy technology between a few vehicles. We presented some aspects of the decision problem of graphic train timetable construction with regard to recuperation. As an indicator of quality...
-
Numerical modeling of GPR field in damage detection of a reinforced concrete footbridge
PublikacjaThe paper presents a study on the use of the ground penetrating radar (GPR) method in diagnostics of a footbridge. It contains experimental investigations and numerical analyses of the electromagnetic field propagation using the finite difference time domain method (FDTD). The object of research was a reinforced concrete footbridge over a railway line. The calculations of the GPR field propagation were performed on a selected cross-section...
-
Correction of determined coordinates of railway tracks in mobile satellite measurements
PublikacjaThis article examines one of the basic issues related to the technique of mobile satellite measurements in railway tracks. This problem concerns the correction of the determined coordinates of the track centerline. The need to perform this operation results from the GNSS receivers positioning at a certain height above the level of the existing track axis, leading to longitudinal and lateral shifts of antennas. The key problem here...
-
Obliczanie robót ziemnych przy modernizacji linii kolejowych
PublikacjaW artykule omówiono kolejny etap prac nad programem MUGO dotyczący obliczeń robót ziemnych. Program jest związany z modernizacją układów geometrycznych toru kolejowego. W pracy pokazano metodykę obliczania pól powierzchni nasypów na linii jednotorowej.
-
DYNAMIC ANALYSIS OF THE RAILWAY BRIDGES IN POLAND WITH REGARDS TO HIGH-SPEED TRAINS PASSAGE ADJUSTMENT
PublikacjaThe dynamic analysis of the railway bridge in Tczew was carried out in the article as an example of such bridges adaptation suitability to handle high-speed trains. Calculations of railway bridges are greatly complicated and labor-consuming. The bridge model and a rolling stock passage simulation were developed in the SOFISTIK software. Three types of elements were used for the correct mapping of the structure in the calculation...
-
The role and scope of architectural and conservation research procedures in the process of restoring the splendour of an architectural monument created after 1945 on the example of the Suburban Railway Station in Gdynia
PublikacjaModern Movement buildings, despite their relatively recent construction, are sometimes affected by radical transformations of layout and form. The railway stations being one of the most important public buildings in the city are a special group of them. Due to long-term and intensive use they may bear the signs of exploitation of parts of its substance and have secondary transformations disharmony with the building. The subject...
-
Transition curve with smoothed curvature at its ends for railway roads
PublikacjaIn the paper, in view of a railway ballasted track, a new concept of transition curve of linear form of curvature along its length and smoothed extreme regions is presented. For this purpose use has been made of an original, universal method for identifying transition curves by means of differential equations. Some general curvature equations for three regions investigated have been determined to be followed by appropriate parametric...
-
Analysis of Measurement Errors in Rail Vehicles’ Pantograph Inspection System
PublikacjaThe paper presents an approach to evaluation of height measurement errors in laser scanning inspection system. The system, consisting of a laser line generator and a specialized camera, is dedicated to diagnosing carbon contact strips of railway vehicles’ pantographs. While height measurement resolution is easily computable based on system parameters, determining the measurement error is troublesome due to numerous impacts. As...
-
Safety at railway level crossings and Vision Zero
PublikacjaIn this work, safety analysis at the railway level crossings is presented using advanced mathematical modelling. Resistivity of track subgrade panels is taken into account. The analysis does not refer to the assessment of the current regulations. Specific cases of generalized dynamic system are considered by introducing operations S=Δ, S=P defined in space C(N) of real sequences. In this model, generalized discrete exponential...
-
Dynamics of the small-span railway bridge under moving loads
PublikacjaThe paper presents the results of dynamic analysis of the small-span railway bridge, subjected to an action of moving trains. Numerical simulations were performed using three different load models: series of moving forces, series of moving single-mass and double-mass oscillators. The parameters of the vehicle were taken from the existing EN57 train. The parameters of the bridge were taken from the existing steel span of 10,24 m...
-
Degradation of the Concrete Railway Track Bed Located in the Vicinity of the Loading Wharf
PublikacjaThe following article describes the damages of the concrete railway track bed at the place of unloading petroleum products located in the immediate vicinity of the cargo berth. The concrete of the track bed has been a subject to degradation as a result of many years of exploitation resulting, inter alia, in its cyclical flooding of petroleum products during the unloading and loading of rail tankers. Repairs carried out in the previous...
-
DYNAMIC RESPONSE OF FORUM GDANSK STRUCTURE DUE TO RAIL TRAFFIC
PublikacjaThe paper presents the study of the impact of vibration induced by the movement of the railway rolling stock on the Forum Gdańsk structure. This object is currently under construction and is located over the railway tracks in the vicinity of the Gdańsk Główny and Gdańsk Śródmieście railway stations. The analysis covers the influence of vibrations on the structure itself and on the people within. The in situ measurements on existing...
-
Study on the Positioning Accuracy of the GNSS/INS System Supported by the RTK Receiver for Railway Measurements
PublikacjaCurrently, the primary method for determining the object coordinates is positioning using Global Navigation Satellite Systems (GNSS) supported by Inertial Navigation Systems (INS). The main goal of this solution is to ensure high positioning availability, particularly when access to satellite signals is limited (in tunnels, areas with densely concentrated buildings and in forest areas). The aim of this article is to determine whether...
-
Displacement measurements during load testing of railway arch bridge
PublikacjaThe paper discusses issues concerning load tests carried out on a twin-track, arch railway bridge over the Martwa Wisla river in Gdansk. Currently, it is the bridge with the longest span in its class in Poland. The load-bearing structure consists of three no-hinge arches and an orthotropic deck suspended from them. The studies of the structure assumed the performing of static and dynamic tests. The paper presents the method for...
-
New transition curve adapted to railway operational requirements
PublikacjaThe paper points to the limited possibilities of improving the existing situation in the area of transition curves used in geometrical layouts of the railway track. Difficulties in the practical implementation and maintenance of very small horizontal ordinates of the transition curve and the ordinates of the gradient due to cant in the initial section, appearing on smooth transition curves, were indicated. The main reason for this...
-
Ocena klimatu akustycznego w przestrzeni pasażerskiej elektrycznego zespołu trakcyjnego serii EN57
PublikacjaW pracy przedstawiono wyniki badań poziomów dźwięku w przestrzeni pasażerskiej elektrycznego zespołu trakcyjnego (EZT) serii EN57 podczas postoju, rozruchu, jazdy oraz hamowania. Badania przeprowadzono na podstawie autorskiej metodyki badawczej bazując na normie PNEN ISO 3381:Kolejnictwo. Akustyka. Pomiar hałasu wewnątrz pojazdów szynowych. Badania przeprowadzono na linii kolejowej nr 250 od przystanku Gdańsk Śródmieście do stacji...
-
Modal analysis of railway current collectors using Autodesk Inventor
PublikacjaThe paper presents the results of modal analysis of railway current collector type 160EC. In the first place, the analysis was carried out analytically for a simplified two lumped mass pantograph model. Then numerical analysis was conducted in the Autodesk Inventor (AI) on the prepared multibody model using the AI modal analysis algorithm, which is based on the finite element method (FEM). Model elements which are most relevant...
-
OCENA WŁAŚCIWOŚCI STALI STOSOWANEJ W STARYCH OBIEKTACH KOLEJOWYCH
PublikacjaThe scope of the paper is to give an introduction to the assessment subject matter of steel properties used in old railway bridges. The mechanical and chemical properties of construction steel extracted from old steel bridges are generally investigated by tensile tests, impact tests through the Charpy pendulum impact V-notch, and an optical emission spectrometer. Besides descriptions of the tests, the chosen chemical and mechanical...
-
Determination of non-steroidal anti-inflammatory drugs in natural waters using off-line and on-line SPE followed by LC coupled with DAD-MS
PublikacjaOpisano dwie metody pozwalające na jednoczesne oznaczanie zawartości niesterydowych leków przeciwzapalnych (difluisal, diklofenak, naproksen, tolmetin, fenoprofen, ibuprofen) w próbkach wodnych. Próbki przygotowywano do analizy z użyciem techniki ekstrakcji do fazy stałej (off-line i on-line). Natomiast oznaczeń końcowych dokonano z użyciem LC-DAD-MS. Sprawdzono kilka różnych kolumienek ekstrakcyjnych i wybrano RP-18 jako najlepsze...
-
Usługi on-line w kontekście mobilnym - jakościowe badanie obserwacyjne
PublikacjaArtykuł przedstawia wyniki badania obserwacyjnego, majacego na celu zidentyfikowanie czynników kształtujących u użytkowników chęć skorzystania z usług on-line za pomocą urządzeń mobilnych takich jak smartfon, tablet lub laptop. Przeprowadzono badania obserwacyjne, w których użytkownicy (7 osób) przez 14 dni notowali swoją aktywność w zakresie korzystania z usług on-line z dostępnych urządzeń w powiązaniu z czynnikami uznawanymi...
-
Reprezentation of mechanic hysteresis in a railway track using the Preisach model
PublikacjaThis paper presents an implementation of the classic scalar Preisach model to describe the hysteresis phenomenon created in a railway track subjected to lateral (in the horizontal plane) displacements. The principles of the Preisach theory and the scalar mathematical model of the mechanical hysteresis that is based on statistically distributed modified hysteresis operators are briefly presented. This article presents the characteristic...
-
Arching of railway turnouts by analytical design method
PublikacjaThe paper involved the issue of arching of the railway turnouts. This is an issue which is given relatively less attention to scientific and research activities. Reference has been made to the book by Wladyslaw Rzepka, under the title „Curved turnouts in plan and profile”, which has been used in Poland for more than 50 years as the main source of information relating to the turnouts on the curve. The book is a compilation of elaborations...
-
Accuracy assessment of mobile satellite measurements in relation to the geometrical layout of rail tracks
PublikacjaThe paper presents the campaigns of mobile satellite measurements, carried out in 2009–2015 on the railway and tram lines. The accuracy of the measurement method has been analysed on the basis of the results obtained in both horizontal and vertical planes. The track axis deviation from the defined geometric shape has been analysed in the areas clearly defined in terms of geometry, i.e. on the straight sections and sections with...
-
Elipsometric data analysis used in on-line metal passivation monitoring
PublikacjaWykorzystano technikę elipsometrii monochromatycznej do opisu on-line warstw tlenkowych, elektroosadzanych na miedzi. Elipsometria jest w stanie dostarczyć informacji odnośnie grubości i współczynników załamania światła układów warstwowych, jednakże wymagane w tym celu jest zbudowanie matematycznego modelu odwzorowującego stałe optyczne układu badanego. W powyższej pracy przedyskutowane zostały różne metody dopasowywania modelu...
-
Determination of safety indicators of the freight wagons by mobile systems
PublikacjaThe organization of the movement of freight trains in Ukraine is an important factor in integrating the country’s railway transport into the European system. A situation that requires a significant renewal of the freight wagon park with modern wagons to meet the freight transportation requirements has arisen. Also, a significant drawback of railway transport in Ukraine is the limitation of the speed of trains, which include freight...
-
Diagnostics of the tram track shape with the use of the global positioning satellite systems (GPS/Glonass) measurements with a 20 Hz frequency sampling
PublikacjaSatellite geodetic measurements used in the diagnosis of railway tracks require professional receivers and a very high frequency rate of data processing. It stems from a significant speed (10 km/h) kinematic measurements carried out during the passage of a measuring platform. The survey results (positions) of deformed railroad track have waveforms nature requiring additional processing methods and approximations. Due to the announcement...
-
Numeryczna analiza dynamiczna wieszaków w łukowym wiadukcie kolejowym. Analiza przypadku
PublikacjaW artykule przedstawiono analizę dynamiczną wiaduktu kolejowego w ciągu Centralnej Magistrali Kolejowej zlokalizowanego koło Huty Zawadzkiej. W analizie zwrócono szczególną uwagę na lokalną odpowiedź wieszaków na obciążenie przejeżdżającym pociągiem oraz wiatrem. Obliczenia przeprowadzono na podstawie wykonanego modelu MES. Zweryfikowano poprawność modelu poprzez porównanie uzyskanych wyników z wartościami pomierzonymi. Przeprowadzono...
-
Nośność konstrukcji gruntowo-łukowej prefabrykowanego wiaduktu w świetle obliczeń numerycznych i badań „in situ”
PublikacjaWartykule przedstawiono analizy przeprowadzone dla wiaduktu WK-15 Pomorskiej Kolei Metropolitalnej wykonanego w technologii łuków prefabrykowanych przykrytych gruntem (system TechSpan). W celu weryfikacji obliczeń numerycznych wykonano próbne obciążenie konstrukcji. Przedstawiono wyniki pomiarów naprężeń i prezmieszczeń konstrukcji. Odniesiono się krytycznie do zastosowanego modelu obliczeniowego.
-
DYNAMIC ANALYSIS OF HISTORIC RAILWAY BRIDGES IN POLAND IN THE CONTEXT OF ADJUSTING THEM TO PENDOLINO TRAINS
PublikacjaThe article presents the dynamic analysis of the historic railway bridge in Tczew as an example of the usefulness of such type of bridge for high-speed trains. The model of the bridge and the simulation of rolling stock passage was performed in SOFISTIK program. The scope of work includes experimental studies, the solution of the problem concerning the correct solution features dynamic model takes into account the dependencies...
-
Koncepcja zdalnego sterowania i monitoringu urządzeń trakcyjnych z wykorzystaniem technologii teleinformatycznych
PublikacjaAdvancement in wireless communication enables engineers to apply sophisticated and relatively inexpensive technologies in new fields of industry, which were previously designated solely to wire-based solutions. One of those fields is railway transportation system. In effect of a high reliability and safety demands, this area was resistive to new technologies. Nowadays, increased security and reliability of wireless sensor networks...
-
Forecasting of railway track tamping based on settlement of sleepers using fuzzy logic
PublikacjaThe sleepers in a railway track transfer vertical, transverse and longitudinal loads to the track ballast and subgrade. The sleepers allow for keeping the distance between the rails constant. The thickness of ballast should be between 16 and 35 cm depending on the design standard of the track, and it should be densified where the ballast supports the sleeper. The exploitation causes contamination of the ballast, crushing the material...