Filtry
wszystkich: 3369
wybranych: 2270
-
Katalog
- Publikacje 2270 wyników po odfiltrowaniu
- Czasopisma 47 wyników po odfiltrowaniu
- Konferencje 7 wyników po odfiltrowaniu
- Osoby 43 wyników po odfiltrowaniu
- Projekty 3 wyników po odfiltrowaniu
- Zespoły Badawcze 1 wyników po odfiltrowaniu
- Kursy Online 18 wyników po odfiltrowaniu
- Dane Badawcze 980 wyników po odfiltrowaniu
Filtry wybranego katalogu
wyświetlamy 1000 najlepszych wyników Pomoc
Wyniki wyszukiwania dla: MEASUREMENT OF RAIL DEFECTS
-
Investigation on accelerated impedance spectrum measurement method with multisine signal stimulation
PublikacjaThe paper presents an investigation on the accelerated impedance spectrum measurement method, oriented at parameter identification of technical objects modelled by a linear equivalent circuit, e.g. anticorrosion coatings.The method is based on multisine signal stimulation of an object and response analysis by triangle window filterbanks.It has several advantages, as compared with conventional point-by-point spectrum measurement....
-
Measurement Campaign and Mathematical Model Construction for the Ship Zodiak Magnetic Signature Reproduction
PublikacjaThe paper presents the partial work done within the framework of the EDA Siramis II project focused on magnetic signature reproduction of ships. Reproduction is understood here as the ability to determine the magnetic anomaly of the local Earth magnetic field in any direction and at any measurement depth due to the presence of the analysed object. The B-91 type hydrographic ship Zodiak was selected as the real case study. The work...
-
Is mesh fixation necessary in laparoendoscopic techniques for M3 inguinal defects? An experimental study.
Publikacjarepairs, in case of large direct hernias (M3) mesh fixation is recommended to reduce recurrence risk. Despite lack of highquality evidence, the recommendation was upgraded to strong by expert panel. The authors conducted a research experiment to verify the hypothesis that it is possible to preserve the mesh in the operating field in large direct hernias (M3) without the need to use fixing materials. Method The authors conducted...
-
Comparison of induction motor bearing diagnostic test results through vibration and stator current measurement
PublikacjaThe paper discusses results of tests performed by authors, related to the angine bearings diagnostic using vibration and stator current measurements. The paper contains the description of an automatic measurement system, developed for measurement of those harmonics and processing that to obtain bearing diagnostic information. System was tested on objects with intentionally made defects in bearings, results of this test was also...
-
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...
-
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...
-
Development of the urban rail vehicle acoustic model
Publikacja -
Increasing rail life by forecasting fatigue failure.
PublikacjaReferat poświęcony jest przedłużaniu żywotności szyn i obejmuje zagadnienia prognozowania liczby pęknięć a także planowania szlifowań szyn. Dane pomiarowe pochodzą z wieloletnich badań przeprowadzonych w Katedrze Inżynierii Kolejowej Politechniki Gdańskiej na liniach magistralnych PKP.
-
Comparison of the tests for equivalence of the measurement methods for measurement of PM10 dust in ambient air
PublikacjaThe paper presents the motives for conducting the equivalence tests and the reasons of discrepancies between the results of PM10 dust concentration obtained via the reference method and the methods based on 'on-site' measurement. The reference and non-reference methods of measurement of PM10 dust concentration in air have been discussed. Field tests for equivalence, following the Polish standard and the European Union (EU) guidelines,...
-
Nondestructive global corrosion measurement using guided wavefield data
PublikacjaMetallic structures often face degradation, and corrosion ranks among the most prevalent forms of deterioration. Accurate quantification of corrosion is crucial, especially for structures exposed to harsh environmental conditions, such as marine vessels and offshore installations. Because the traditional measurement methods based on scanning by ultrasonic gauge are time-consuming and provide only rough information on the thickness...
-
BJS-03 DO WE NEED FIXATION OF THE MESH IN LAPAROENDOSCOPIC TECHNIQUES FOR M3 INGUINAL DEFECTS? AN EXPERIMENTAL STUDY
PublikacjaThe authors conducted a research experiment to verify the hypothesis that it is possible to preserve the mesh in the operating field in large direct hernias (M3) without the need to use fixing materials. The results showed that mesh fixation is not the only alternative to preventing recurrence in complex defects and that the type of implant seems to be a key factor from the point of view of mechanics and biophysics.
-
Laser-textured cross-hatched surface topography analysis with evaluation of high-frequency measurement noise
PublikacjaThe precision of surface roughness determination using ISO 25178 parameters relies on various factors that directly impact the measurement process. In industry applications, the contactless roughness measurement reduces data collection time. However, it introduces several potential errors, including those stemming from the environment. One of the main types of errors encountered during topography analysis is measurement noise,...
-
Topography measurement methods evaluation for entire bending-fatigued fracture surfaces of specimens obtained by explosive welding
PublikacjaIn this paper, the methods of compensation of differences in the results of entire bending-fatigued fracture surface topographies were presented. The roughness evaluation was performed with a focus variation microscope and confocal surface topography measurement techniques. The differences in the ISO 25178 roughness parameters were investigated and procedures for their compensation were studied. It was found that various types...
-
A Method for Determination and Compensation of a Cant Influence in a Track Centerline Identification Using GNSS Methods and Inertial Measurement
PublikacjaAt present, the problem of rail routes reconstruction in a global reference system is increasingly important. This issue is called Absolute Track Geometry, and its essence is the determination of the axis of railway tracks in the form of Cartesian coordinates of a global or local coordinate system. To obtain such a representation of the track centerline, the measurement methods are developed in many countries mostly by the using...
-
Tool support for detecting defects in object-oriented models
PublikacjaArtykuł przedstawia nową metodę analityczną UML-HAZOP oraz narzędzie wspomagające jej stosowanie. Metoda ukierunkowana jest na wykrywanie defektów we wczesnych fazach wytwarzania oprogramowania i koncentruje się na powszechnie stosowanych modelach opartych na metodyce obiektowej.
-
Surface layer defects on injection-molded plastic components
PublikacjaProces wtryskiwania jakkolwiek jest powszechnie stosowany w przemyśle nie jest jeszcze do końca przebadany. W pracy przedstawiono model i symulację numeryczna procesu wtryskiwania wykonaną na bazie programu FIDAP. Na tej podstawie przedstawiono proces zachowania się tworzywa podczas procesu wtryskiwania w strefie przyściennej formy. Wyniki z symulacji porównano z danymi ekspermentalnymi.
-
A measurement method for lossy capacitive relative humidity sensors based on a direct sensor-to-microcontroller interface circuit
PublikacjaA new time-domain measurement method for determining the capacitance and resistance values of lossy relative humidity capacitive sensors is presented. The method is based on a direct sensor-to-microcontroller interface for microcontrollers with internal analog comparators and timers. The interface circuit consists only of four reference resistors (two reference resistors if a microcontroller includes a voltage reference source),...
-
Tailoring Defects in B, N-Codoped Carbon Nanowalls for Direct Electrochemical Oxidation of Glyphosate and its Metabolites
PublikacjaTailoring the defects in graphene and its related carbon allotropes has great potential to exploit their enhanced electrochemical properties for energy applications, environmental remediation, and sensing. Vertical graphene, also known as carbon nanowalls (CNWs), exhibits a large surface area, enhanced charge transfer capability, and high defect density, making it suitable for a wide range of emerging applications. However, precise...
-
Determining nominal values basing on the measured rail irregularities
PublikacjaW referacie przedstawiono metodę optymalnego wyznaczania wartości nominalnych na podstawie pomierzonych nierówności toru. Idea proponowanej metody polega na zaprojektowaniu nowego układu geometrycznego wpisanego w istniejący układ stycznych, tzn. bez zmiany kąta zwrotu trasy. Wyznaczone wartości nominalne są wielkościami optymalnymi, tj. takimi dla których odchyłki będą najmniejsze, z jednoczesnym zachowaniem wymagań normowych.W...
-
Finding deformation of the straight rail track by GNSS measurements
PublikacjaW 2009 roku na Politechnice Gdańskiej i Akademii Marynarki Wojennej w Gdyni zostały przeprowadzone, po raz pierwszy, ciągłe pomiary satelitarne toru kolejowego z wykorzystaniem względnej metody fazowej na bazie polskiej Aktywnej Sieci Geodezyjnej ASG-EUPOS i serwisu czasu rzeczywistego RTK (GPRS) - NAVGEO. Przeprowadzona analiza wykazała silny związek między lokalizacją odbiornika GNSS i dokładnością wyznaczania pozycji, wpływ...
-
Investigations of methods to measure longitudinal forces in continuous welded rail tracks using the tamping machine.
PublikacjaPraca przedstawia w sposób poglądowy próby znalezienia efektywnej metody określania sił podłużnych w szynach toru bezstykowego. Szczególną uwagę poświęcono metodzie wymuszonych przemieszczeń poprzecznych. Podstawowym stwierdzeniem z przeprowadzonych własnych badań była konieczność odejścia od podnoszenia odłączonego od podkładów odcinka szyny i skoncentrowanie się na przemieszczeniach poprzecznych; doprowadziło to koncepcji zastosowania...
-
Low-coherence method of hematocrit measurement
PublikacjaDuring the last thirty years low-coherence measurement methods have gained popularity because of their unique advantages. Low-coherence interferometry, low-coherence reflectometry and low-coherence optical tomography offer resolution and dynamic range of measurement at the range of classical optical techniques. Moreover, they enable measurements of the absolute value of the optical path differences, which is still an unsolved problem...
-
A Surrogate-Assisted Measurement Correction Method for Accurate and Low-Cost Monitoring of Particulate Matter Pollutants
PublikacjaAir pollution involves multiple health and economic challenges. Its accurate and low-cost monitoring is important for developing services dedicated to reduce the exposure of living beings to the pollution. Particulate matter (PM) measurement sensors belong to the key components that support operation of these systems. In this work, a modular, mobile Internet of Things sensor for PM measurements has been proposed. Due to a limited...
-
A measurement system for children endurance tests
PublikacjaThere are a lot of ethical problems concerning the use of invasive methods for the measurement of a child's body response to physical exercise and physical training. The alternative is are non-invasive methods like ergospirometry or NIRS. The article presents a measurement system dedicated for children endurance tests, composed of a few non-invasive measurement modules, including a temperature measurement module. Temperature is...
-
Uncertainty of mass flow measurement using centric and eccentric orifice for Reynolds number in the range 10,000 ≤ Re ≤ 20,000
PublikacjaThe article analyses the impact of the Reynolds number on the estimated uncertainty of the mass flow rate measurement using an orifice plate. The objects of the research were two types of orifices: centric (ISA) and eccentric, with the diameter ratio β = 0.5. Studies were performed by Monte Carlo simulation and experiments for Reynolds numbers in the range 10,000 ≤ Re ≤ 20,000. The obtained results have shown that for both orifice...
-
Effect of Time Varying Measurement Conditions on Antenna Pattern in Near Field Measurement and Its Correction Procedure
PublikacjaAuthors present the procedure of taking into account the changes of electrical parameters of setup due to the time drift of temperature during the procedure of near field measurement. It is proposed to make additional measurements in determined positions of probe are next used the results to introduce corrections terms in measured data. Such approach was verified practically in experimental near field measurement system.
-
A measurement method for capacitive sensors based on a versatile direct sensor-to-microcontroller interface circuit
PublikacjaIn the paper, there is presented a new time-domain measurement method for determining the capacitance values of capacitive sensors, dedicated, among others, to capacitive relative humidity sensors. The method is based on a versatile direct sensor-to-microcontroller interface for microcontrollers with internal analog comparators (ACs) and with precision voltage reference sources, e.g. digital-to-analog converters (DACs). The reference...
-
Diamond protection for reusable ZnO coated fiber-optic measurement head in optoelectrochemical investigation of bisphenol A
PublikacjaDue to the global problem with plastic contaminating the environment, with bisphenol A (BPA) being one of the highest demand, effective monitoring and purification of the pollutants are required. The electrochemical methods constitute a good solution but, due to polymerization of electrochemical oxidation bisphenol A products and their adsorption to the surfaces, measurement head elements are clogged by the formed film. In this...
-
Impact of probability distribution on the uncertainty of resistance measurement
PublikacjaThe paper presents studies on the influence of probability distributions on the expanded uncertainty of the resistance measurement. Choosing the correct probability distribution is very important to estimate of measurement uncertainty. The paper presents the results of analysis of the resistance measurement uncertainty using the technical method of resistance: 100 G. The analysis of the uncertainty...
-
On determining defects identity in carbon nanotubes using charge probes
Publikacja -
Detecting defects in object-oriented diagrams using UML-HAZOP
PublikacjaArtykuł dotyczy metody wykrywania defektów w dokumentacji oprogramowania wykonywanego z zastosowaniem notacji UML. Metoda ta, nazwana UML-HAZOP, jest adaptacją metody HAZOP szeroko stosowanej w stosunku do systemów związanych z bezpieczeństwem. Metoda ta jest ukierunkowana na wykrywanie anomalii w dokumentacji projektowej na drodze analizy ''przepływów'' pomiędzy komponentami badanego systemu. Adaptacja metody do badania oprogramowania...
-
Evaluation of wow defects based on tonal components detection and tracking
PublikacjaReferat przedstawia opis metody wyznaczania charakterystyki pasożytniczego kołysania dźwięku. W metodzie wykorzystuje się informacje o zmianach tonalnych składowych dźwięku wyszukiwanych w kolejnych ramkach czasowych. Komponenty tonalne z poszczególnych ramek łączone są w ścieżki. Na podstawie tych trajektorii tworzona jest krzywa PVC obrazująca pasożytnicze zmiany dźwięku. Krzywa PVC może być wykorzystana do usunięcia pasożytniczego...
-
Distance measurement errors in silent FM-CW sonar with matched filtering
PublikacjaThe secretiveness of sonar operation can be achieved by using continuous frequency-modulated sounding signalswith reduced power and significantly prolonged repeat time. The application of matched filtration in the sonarreceiver provides optimal conditions for detection against the background of white noise and reverberation, and avery good resolution of distance measurements of motionless targets. The article shows that target...
-
USE OF LANGMUIR PROBE IN DIESEL ENGINE DIAGNOSTIC RESEARCH Part I MEASUREMENT TECHNOLOGY. - Part 1 : MEASUREMENT TECHNOLOGY
PublikacjaIn the paper, the basic assumptions of diesel engine cylinder system's diagnosing method, based on observation of emerging and moving electric charges of ionized gas in the combustion workspaces, using Langmuir's probe. In the first part of the paper, only the technology of the measurement and results of the preliminary diagnostic tests of laboratory engine Farymann Diesel D10 were presented. The primary purpose of the research...
-
Reliability And Maintenance Analysis Of CCTV Systems Used In Rail Transport
Publikacja -
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...
-
Remote current measurement with FPGA digital processing
PublikacjaThe work presents an implementation of a modular measurement and control systemthat controls variants of mains supply of 230V electrical equipment. The system allowsto supervise power consumption in the office electronic equipment. The system detectsthe instant of the reduced power consumption by a device and makes possible itsswitch-off in order to reduce energy cost. The current is measured with integratedcurrent/voltage converters....
-
A concept of measurement system based on the Z-Wave standard
PublikacjaIn the paper a new concept of measurement system based on the Z-Wave standard is presented. This standard is dedicated to use mainly in home automation systems, but its properties enable to use it in dispersed measurement systems and support wireless communication between measurement nodes in a mesh-type network. In the paper basic metrological aspects of the Z-Wave standard and an example of impedance measurement system are discussed.
-
Scalable Measurement System for Multiple Impedance Gas Sensors
PublikacjaAuthor proposes scalable architecture of the measurement system for gas sensor with impedance dependance of the gas concentration. The main part of the system is a single-board impedance analyser. The number of analysers working in parallel can be configured according to specific application. The system is controlled by a single computer which organises the measurement cycle and store the acquired measurement data. The system is...
-
Discrete measurement of fault-arc velocity
PublikacjaOpisano metodę dyskretnego pomiaru prędkości jednofazowego łuku awaryjnego poruszającego się w płaskim, poziomym układzie szyn. Badania przeprowadzono za pomocą punktowych czujników optycznych rozmieszczonych równomiernie wzdłuż szyn. Podano opis układu, jego charakterystykę, wpływ obszaru zjonizowanego na uzyskiwane wyniki i zależności między obserwowanymi wielkościami.
-
Method of earth fault loop impedance measurement without nuisance tripping of RCDs in 3-phase low-voltage circuits
PublikacjaVerification of electrical safety in low-voltage power systems includes the measurement of earth fault loop impedance. This measurement is performed to verify the effectiveness of protection against indirect contact. The widespread classic methods and meters use a relatively high value of the measuring current (5–20) A, so that they are a source of nuisance tripping of residual current devices (RCDs). The meters dedicated to circuits...
-
Analysis of Ceramic Elements with Ring-Crack Defects in Lubricated Rolling Contact
PublikacjaThe properties of ceramics, specifically low density, high hardness, high temperature capability and low coefficient of thermal expansion are of most interest to rolling element manufacturers. Surface ring cracks on lubricating rolling contact fatigue failure has been studied using numerical fracture analysis. Such cracks are very often found on ceramic bearing balls and decrease fatigue life rapidly. The numerical calculations...
-
Disentangling Red Emission and Compensatory Defects in Sr[LiAl3N4]:Ce3+ Phosphor
Publikacja -
Application of principal component and hierarchical cluster analysis in classifying defects of trolleybuses
PublikacjaThe failure rate of vehicles is a relevant task, which is strictly connected with the reliability of transportation systems. Methods of data analysis allow us to find similarity and differences between failure rates of several parts of trolleybuses. This paper deals with the statistic of failure of trolleybuses from the municipal transport company of Gdynia (Poland).
-
An analysis of a measurement probe for a high impedance spectroscopy analyzer
PublikacjaW artykule przedstawiono sondę będącą obwodem wejściowym analizatora do spektroskopii wysokoimpedancyjnej. Sonda umożliwia pomiar impedancji jednym zaciskiem uziemnionej w zakresie od 100ohm do 100Gohm. Sonda umożliwia wydzielenie dwóch sygnałów proporcjonalnych do prądu i napięcia na impedancji mierzonej w szerokim zakresie częstotliwosci od 100uHz do 100MHz.Przeprowadzono analizę sondy w której uwzględniono najważniejsze czynniki...
-
An analysis of a measurement probe for a high impedance spectroscopy analyzer
PublikacjaW artykule przedstawiono sondę będącą obwodem wejściowym analizatora do spektroskopii wysokoimpedancyjnej. Sonda umożliwia pomiar impedancji jednym zaciskiem uziemnionej w zakresie od 100ohm do 100Gohm. Sonda umożliwia wydzielenie dwóch sygnałów proporcjonalnych do prądu i napięcia na impedancji mierzonej w szerokim zakresie częstotliwości od 100uHz do 100MHz.Przeprowadzono analizę sondy w której uwzględniono najważniejsze czynniki...
-
Synchro-photogrammetry in the measurement of objects in motion - the case study
PublikacjaSynchronous photographs and digital photogrammetry methods in a measurement of objects in motion - the experiment. In the following paper, a case study example of a photogrammetric method based on synchronous digital photographs has been presented. This measurement method is an effective solution for tracking of moving objects, dynamic studies and dimensioning of geometry movements. Nowadays, the use of synchronous photography...
-
A Stand for Measurement and Prediction of Scattering Properties of Diffusers
PublikacjaIn this paper we present a set of solutions which may be used for prototyping and simulation of acoustic scattering devices. A system proposed is capable of measuring sound field. Also a way to use an open source solution for simulation of scattering phenomena occurring in proximity of acoustic diffusers is shown. The result of our work are measurement procedure and a prototype of the simulation script based on FEniCS - an open source...
-
Velocity measurement using the fdoa method in ground-based radio navigation system
PublikacjaVelocity is one of the main navigation parameters of the moving objects. However some systems of position estimation using radio wave measurements cannot provide velocity data due to limitation of their performance. In this paper a velocity measurement method for DS-CDMA radio navigation system is proposed, which doesn’t require full synchronization of reference stations carrier frequencies. The article presents basics of FDOA...
-
Optimization of multilayer rail substrate under moving load, using metamaterials.
Publikacja