Filtry
wszystkich: 1286
-
Katalog
wyświetlamy 1000 najlepszych wyników Pomoc
Wyniki wyszukiwania dla: LARYNX VIBRATION
-
A technique of experiment aided virtual prototyping to obtain the best spindle speed during face milling of large-size structures
PublikacjaThe paper presents an original method concerning vibration suppression problem during milling of large-size and geometrically complicated workpieces with the use of novel way of selecting the spindle speed. This consists in repetitive simulations of the cutting process for subsequent values of the spindle speed, until the best vibration state of the workpiece is reached. An appropriate method of obtaining a computational model,...
-
RAPORT - EKSPERTYZA Z POMIARÓW DRGAŃ LINII WAŁÓW NA JEDNOSTCE ORP „DĄBIE”
PublikacjaEkspertyza diagnostyczna dotycząca stanu technicznego dwóch linii transmisji mocy (linii wałów) opracowana na podstawie przeprowadzonych pomiarów drgań w 26 punktach pomiarowych, przy jednoczesnej pracy silników napędowych L i PB (wspólnej pracy linii wałów obu burt), w II zakresach ustalonego obciążenia „pół-naprzód” i „cała-naprzód”. Pomiary prędkości i przyspieszeń drgań generowanych przez węzły konstrukcyjne okrętowego układu...
-
Wave Method for Structural Health Monitoring: Testing Using Full-Scale Shake Table Experiment Data
PublikacjaAn algorithm of the wave method for structural health monitoring (SHM) is tested and calibrated using shake table experiment data of a full-scale, seven-story, reinforced-concrete building slice. The method is based on monitoring changes in the velocity of waves propagating vertically through the structure, identified by least-squares (LSQ) fit of beam models. The experiment was conducted by a team from the University of California,...
-
Idea zastosowania sztucznej inteligencji w prognozowaniu wpływu drgań komunikacyjnych na odpowiedź dynamiczną budynków mieszkalnych
PublikacjaW poniższym artykule autorzy analizują wpływ drgań komunikacyjnych na budynki mieszkalne oraz metodykę pomiarową według PN-85 B-02170 [1]. Problemem badawczym jest opracowanie prostej metody prognozowania wpływu drgań na budynki mieszkalne w taki sposób, aby nie było konieczne przeprowadzanie pracochłonnych i kosztownych pomiarów polowych. W tym celu wykonano analizę przy użyciu algorytmów opartych na sztucznej inteligencji oraz...
-
Granular cell tumor, NOS - Male, 37 - Tissue image [7260729594498221]
Dane BadawczeThis is the histopathological image of LARYNX tissue sample obtained in Medical University Gdańsk and deposited in ZMDL-GUMED. The sample image was taken using: Pannoramic 250 3DHistech slide scanner (20x magnification) and saved to DICOM format.
-
Granular cell tumor, NOS - Male, 37 - Tissue image [7260729594497101]
Dane BadawczeThis is the histopathological image of LARYNX tissue sample obtained in Medical University Gdańsk and deposited in ZMDL-GUMED. The sample image was taken using: Pannoramic 250 3DHistech slide scanner (20x magnification) and saved to DICOM format.
-
Granular cell tumor, NOS - Male, 37 - Tissue image [7260729594499731]
Dane BadawczeThis is the histopathological image of LARYNX tissue sample obtained in Medical University Gdańsk and deposited in ZMDL-GUMED. The sample image was taken using: Pannoramic 250 3DHistech slide scanner (20x magnification) and saved to DICOM format.
-
Metody matematyczne fizyki
Kursy Online -
Statystyka matematyczna
Kursy Online -
Szymon Andrzejewski dr
OsobyUkończył Uniwersytet Gdański na kierunku Politologia, specjalizacja ustrojowo-samorządowa w 2008 roku. Ukończył studia podyplomowe na Politechnice Gdańskiej pod nazwą "Zarządzanie i ewaluacja projektów finansowanych z funduszy Unii Europejskiej" w 2010r. i na Akademii Górniczo-Hutniczej pod nazwą "Ochrona Środowiska przed hałasem i drganiami" w 2012 roku. Student Socjologicznych Studiów Doktoranckich na Uniwersytecie Gdańskim od...
-
Application a laboratory stand for multi-symptoms tests for high cyclic fatigue of constructional material
PublikacjaThis paper describes a need of diagnostics present ship plants according to current technical state. In order to reach competent physical quantity describing fatigue of materials by congregated energy. This paper describes using some diagnostics methods (acoustic emission AE, vibration, thermovision, deformation) in order to definition fatigue state of construction material. The author tries to find correlation between measured...
-
Experimental study on earthquake-induced pounding between steel structures
PublikacjaPounding between adjacent structures has been repeatedly observed during major earthquakes. The phenomenon may cause some local damage at the points of interactions, it may also lead to substantial destruction, permanent deformations or total collapse of colliding structures. The effects of earthquake-induced structural pounding have been studied for more than three decades now. However, most of the studies concerned masonry as...
-
The IPV6 Deployment - Best practices
PublikacjaThe new Internet Protocol IPv6 has been regarded for quite a long time as the only option to ensure uninterrupted operation for the Internet service providers andend-users in the current Internet. The article presents important faets about the IPv6, including current statistics of the IPv4 usage, the IPv6 statistics for Poland comparing to the whole Internet. Moreover, this paper shows important aspeets of migration from IPv4 towards...
-
Prognozowanie wpływu drgań komunikacyjnych na budynki mieszkalne za pomocą sztucznych sieci neuronowych i maszyn wektorów wspierających
PublikacjaDrgania komunikacyjne mogą stanowić duże obciążenie eksploatacyjne budynku, powodując zarysowania i spękania tynków, odpadanie wypraw, zarysowania konstrukcji, pękanie elementów konstrukcji lub nawet zawalenie się budynku. Pomiary drgań na rzeczywistych konstrukcjach są pracochłonne i kosztowne, a co ważne nie w każdym przypadku są one uzasadnione. Celem pracy jest analiza autorskiego algorytmu, dzięki któremu z dużym prawdopodobieństwem...
-
Karol Grębowski dr inż.
OsobyKarol Grębowski (dr inż.) pracuje jako adiunkt w Katedrze Technicznych Podstaw Projektowania Architektonicznego na Wydziale Architektury Politechniki Gdańskiej. Jego badania naukowe dotyczą zjawisk szybkozmiennych zachodzących podczas drgań konstrukcji budowlanych, obiektów mostowych (trzęsienia ziemi) oraz badania w zakresie metodologii projektowania budynków stanowiących system ochrony pasywnej (SOP) odpornych na uderzenia pojazdów...
-
Selection of Organic Coating Systems for Corrosion Protection of Industrial Equipment
PublikacjaThe most important element of corrosion protection in industrial conditions is the protective coating system. However, selecting the right coating can often be a real problem due to the sheer number of coating manufacturers and their products on the market. A quantitative approach based on the data mining technique used to analyze the obtained multi-site exposure data has been proposed. This was demonstrated by the example of the...
-
A Surveillance Of Dynamic Processes in Selected Mechatronic Systems
PublikacjaThe paper concerns development of original method of optimal control at energy performance index and its application to dynamic processes surveillance of some mechatronic systems. The latter concerns chatter vibration surveillance during highspeed slender milling of rigid details, as well as motion control of two-wheeled mobile platform. Results of on-line computer simulations and real performance on the target objects reflect...
-
KONFIGURACJA SIECI LAN TYPU SOHO DO PRACY W INTERNECIE IPv6
PublikacjaArtykuł przedstawia podstawowe problemy występujące przy migracji środowisk małych sieci do obsługi protokołu IPv6. Wraz z problemami przedstawione zostały propozycje metodologii przeprowadzenia migracji i narzędzia wspomagające ten proces. Przedstawiono system wspierający administratorów w migracji zarządzanych przez nich sieci do obsługi protokołu IPv6. Celem pracy jest analiza problemów procesów migracji IPv4 do IPv6 oraz wskazanie...
-
Study of Soil Temperature and Moisture Changes in a Physical Model of an Underground Cable Line
PublikacjaThe ampacity of power cables is highly dependent on the thermal resistivity of the soil in which they are laid. The lower it is, the higher this ampacity. The thermal resistivity of the soil decreases as its moisture increases. Therefore, it is preferable that the soil around the cables has high moisture. Unfortunately, the heat generated in heavily loaded cables causes the migration of moisture from the surrounding soil, which...
-
Dynamic analysis of temporary steel grandstand equipped with different types of bracing system
PublikacjaIn the paper, behaviour of a temporary steel grandstand equipped with two different types of bracing system has been analysed through the numerical study. A typical solution concerning application of a diagonal tubular members has been compared with elements proposed by authors and called polymer dampers. A polymer element consists of two L-shape steel members bonded with polymer mass. The aim of the paper is to verify the effectiveness...
-
Luminescence properties of Eu3+ and Tb3+ doped silica-based xerogels
PublikacjaPure SiO2 xerogels and SiO2 xerogels containing SrF2: Eu3+/: Tb3+ crystals were prepared using sol-gel method. Luminescent spectra showed excitation and emission peaks characteristic to Eu3+ and Tb3+ 4f - 4f transitions. ET Tb3+→Eu3+ has been observed. XRD pattern of SiO2 matrix confirmed lack of long range order. Patterns of SiO2-SrF2:Eu3+ and SiO2-SrF2:Tb3+ showed peaks corresponding to SrF2. SEM images have shown agglomerates...
-
Wykorzystanie sztucznych sieci neuronowych do szacowania wpływu drgań na budynki jednorodzinne
PublikacjaW artykule przedstawiono metodę prognozowania wpływu drgań na budynki mieszkalne z wykorzystaniem sztucznych sieci neuronowych. Drgania komunikacyjne mogą doprowadzić do uszkodzenia elementów konstrukcyjnych, a nawet do awarii budynku. Najczęstszym efektem są jednak rysy, pękanie tynku i wypraw. Metody oparte na sztucznej inteligencji są przybliżone, ale stanowią wystarczająco dokładną i ekonomiczną alternatywę dla tradycyjnych...
-
Identification of hydroacoustic wave sources of ship in motion
PublikacjaThis paper deals with results of identification tests of acoustic field spectrum of underwater noise generated by ship in motion. The field is connected with acoustic activity of ship mechanisms and devices in operation. Vibration energy generated by the mechanisms and devices is transferred through ship structural elements to surrounding water where it propagates in the form of acoustic waves of a broad band of frequencies. In...
-
Elemental and tight monogamy relations in nonsignaling theories
PublikacjaPhysical principles constrain the way nonlocal correlations can be distributed among distant parties. These constraints are usually expressed by monogamy relations that bound the amount of Bell inequality violation observed among a set of parties by the violation observed by a different set of parties. We prove here that much stronger monogamy relations are possible for nonsignaling correlations by showing how nonlocal correlations...
-
Design and Experiments of a Piezoelectric Motor Using Three Rotating Mode Actuators
PublikacjaThis paper represents a numerical and experimental investigation of the multicell piezoelectric motor. The proposed design consists of three individual cells that are integrated into the stator, double rotor, and a preload system combined into a symmetrical structure of the motor. Each of the cells is characterized by a traveling wave and rotating mode motor. A finite element numerical analysis is carried out to obtain optimal...
-
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...
-
Nondestructive Testing of the Miter Gates Using Various Measurement Methods
PublikacjaWhen any problems related to civil engineering structures appear, identifying the issue through the usage of only one measuring method is difficult. Therefore, comprehensive tests are required to identify the main source. The strains and displacement measurements, as well as modal identification, are widely used in the nondestructive testing of structures. However, measurements are usually carried out at several points and confirm...
-
THE METHOD OF MEASURING THE MEMBRANE COVER GEOMETRY USING LASER SCANNING AND SYNCHRONOUS PHOTOGRAMMETRY
PublikacjaThe authors present the experience and results of field studies carried out at the technical acceptance of Forest Opera (name in Polish: Opera Leśna) in Sopot (Poland). An unusual design of covering made in the form of “Sheerfill I” technical fabric membrane required spanned in the form of sails, required the use of terrestrial laser scanning. Such approach allowed for the fast and accurate record of the surface of individual panels...
-
Laboratorium Drgań i Zjawisk Falowych/Laboratory of vibrations and wave phenomena
Kursy Online -
Laboratorium drgań i zjawisk falowych / Laboratory of vibrations and wave phenomena
Kursy OnlineSpecjalność: Fizyka stosowana (WFTiMS),I stopnia - inżynierskie, stacjonarne, 2020/2021 - zimowy (obecnie sem. 3)Specjalność: Inżynieria odnawialnych źródeł energii (WFTiMS),I stopnia - inżynierskie, stacjonarne, 2020/2021 - zimowy (obecnie sem. 3)
-
Nonlinear generation of non-acoustic modes by low-frequency sound in a vibrationally relaxing gas
PublikacjaTwo dynamic equations referring to a weakly nonlinear and weakly dispersive flow of a gas in which molecular vibrational relaxation takes place. are derived. The first one governs an excess temperature associated with the thermal mode, and the second one describes variations in vibrational energy. Both quantities refer to non-wave types of gas motion. These variations are caused by the nonlinear transfer of acoustic energy into...
-
Theoretical study of the photoelectron spectrum of ethyl formate: Ab initio and density functional theory investigation
PublikacjaThe first ionization energy and associated photoelectron spectrum of ethyl formate are investigated with quantum chemistry calculations. The geometries, harmonic vibrational frequencies and first ionization energy are computed at the Hartree-Fock (HF) and at the second order Moller-Plesset perturbation theory (MP2). Moreover, accurate ionization energies are obtained with the Coupled-Cluster theory including singles and doubles...
-
FT-IR studies of molecular interactions in formamide-methanol mixtures
PublikacjaTechniką ATR zmierzono widma FT-IR roztworów metanolu(MeOH) i formamidu(FA) w całym zakresie ich składu. Przeprowadzono analizę faktorową widm, która wykazała obecność dwóch kompleksów molekularnych matanolu z formamidem. Na podstawie profilów stężeniowych indywiduów absorbujących wyznaczono średni skład kompleksów w zależności od składu mieszaniny. Przeprowadzono również analizę pasma CO formamidu metodą widm różnicowych. Wyniki...
-
Role of nitrogen in evolution of sp2/sp3 bonding and optical band gap in hydrogenated carbon nitride
PublikacjaDrastic changes in the bonding are found in amorphous hydrogenated carbon nitride (a-CNx:H) film as a function of nitrogen concentration (or N/C ratio). The total C-sp3 fraction and hardness shows a sharp decrease (at N/C = 0.40) whereas optical band gap and resistivity shows a gradual increase as nitrogen concentration increases from 0.07 to 0.58. Raman spectrum of a-CNx:H film is fitted with both Gaussian (integrated intensity...
-
Own or public? Later livelihoods of Ukrainian war migrant households in Poland
PublikacjaThis paper presents empirical research on the livelihood resources of Ukrainian households that fled to Poland due to the Russian invasion and reside there long term. Using a nationwide sample of these households and an accurate econometric framework, we investigate the factors influencing the role of income from work, other private resources and public assistance in covering their living costs in exile. Our findings confirm the...
-
On Configurability of Distributed Volunteer-Based Computing in the Comcute System
PublikacjaThe chapter proposes additional solutions that can be implemented within the Comcute system to increase its configurability. This refers to configuration of the reliability level in the W and S server layers, static or on-the-fly data partitioning and integration, configuration of the system for processing in the data streaming fashion, extending the system for selection of a project that the client wants to contribute to, ease...
-
Vibration surveillance in the hybrid system using optimal control at energyperformance index. W: Zagadnienia analizy modalnej konstrukcji mechanicz- nych. Praca zbiorowa pod red. T. Uhla. Kraków: Kated. Robotyki i Dynam. Masz. AGH**2003 s. 107-114, 2 rys. 1 tab. bibliogr. 4 poz. Nadzorowanie drgań w układzie hybrydowym z wykorzystaniem strerowania opty- malnego przy energetycznym wskaźniku jakości.
PublikacjaW pracy rozważano nadzorowanie drgań niestacjonarnych układów mechanicznychza pomocą sterowania optymalnego przy energetycznym wskaźniku jakości. Uwzględnienie założenia o możliwości podziału układu na podukład modalny, pod-układ strukturalny oraz podukład łączący umożliwiło opis układu sterowanego we współrzędnych hybrydowych. Rozważania zilustrowano przykładem nadzorowa-nia drgań pomostów wagi kolejowej podczas przejazdu wagonów.
-
Load test of new European record holder in span length among extradosed type bridges
PublikacjaThe article presents acceptance load tests of a newly built extradosed MS-3 bridge located along the national road DK-16 near Ostróda (Poland). The structure features significant dimension in European reference scale. It is a new record holder in span length regarding this distinct bridge category. Its length ranges 206 m. Static and dynamic load tests were performed here. The program was extended by entire structural laser scanning...
-
Hybrid Reduced Model of Continuous System
PublikacjaThe paper introduces an alternative method of modelling and modal reduction of continuous systems. Presented method is a hybrid one. It combines the advantages of modal decomposition method and the rigid finite element method. In the proposed method continuous structure is divided into one-dimensional continuous elements. For each 1D element modal decomposition and reduction is applied. Interactions between substructures are...
-
Underwater acoustic communication system using broadband signal with hyperbolically modulated frequency
PublikacjaThe implementation of reliable acoustic underwater communication in shallow waters is a scientific and engineering challenge, mainly due to the permanent occurrence of the multipath phenomenon. The article presents the concept of a transmission system using a broadband signal with hyperbolically modulated frequency (HFM) to transmit data symbols and synchronize data frames. The simulation tests were carried out in channels with...
-
A New Direct-Sequence Spread Spectrum Signal Detection Method for Underwater Acoustic Communications in Shallow-Water Channel
PublikacjaDirect-Sequence Spread Spectrum (DSSS) is one of the modulation and coding techniques used in Underwater Acoustic Communication (UAC) systems for reliable data transmision even at low signal levels. However, in a shallow water channel, there is a strong multipath propagation which causes a phase fluctuation of the received signal, affecting the performance of the spread-spectrum system. The article presents a differential method...
-
Simulation of Direct-Sequence Spread Spectrum Data Transmission System for Reliable Underwater Acoustic Communications
PublikacjaUnderwater acoustic communication (UAC) system designers tend to transmit as much information as possible, per unit of time, at as low as possible error rate. It is a particularly difficult task in a shallow underwater channel in which the signal suffers from strong time dispersion due to multipath propagation and refraction phenomena. The direct-sequence spread spectrum technique (DSSS) applied successfully in the latest standards...
-
Performance of Coherent Modulation Scheme Used in Acoustic Underwater Communication System
PublikacjaThe development of an acoustic underwater communication system for shallow waters is still a big scientificand construction challenge. Currently, non-coherent modulations in combination with strong channel coding are used to achieve reliable communication with low rate in such a channel. To obtain transmission with a higher transmission rate, it is required to use coherent modulation. This paper presents the assumptions of such...
-
Method for the correlation coefficient estimation of the bottom echo signal in the shallow water application using interferometric echo sounder
PublikacjaThe article presents a new method for the assessment of bottom echo correlation coefficient in the presence of multiple echoes. Bottom correlation coefficient is a parameter that characterizes spatial properties of echo signal. Large variability of the bottom shape or properties (for example caused by the presence of bottom objects) and the presence of the acoustic shadow strongly influence the value of the correlation coefficient....
-
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...
-
Modelling and Identification of Tower Type Historic Buildings
PublikacjaW pracy omawia się problemy modelowania i identyfikacji zabytkowych murowanych budowli wieżowych na przykładzie wieży Twierdzy Wisłoujście. Przedstawiono analizę modalną na podstawie dwukierunkowych pomiarów przyspieszeń na 9 poziomach wieży. Wyniki analizy posłużyły do identyfikacji modelu matematycznego budowli w postaci sztywnego bloku na podłożu sprężystym. Wykorzystano hierarchiczną procedurę opartą na analizie wrażliwości.
-
Dynamics of mechanical model of implant-tissue system in ventral hernia repair
PublikacjaThe paper deals with a finite element modelling of implants in the problem of ventral hernia repair. The synthetic mesh implanted in the abdomen during surgery is here modelled as a membrane structure. Thesystem undergoes the internal abdominal pressure that occurs during the postoperative cough, the load identified in the literature as the main cause of the connection failure and hernia recurrence. The model can be used to estimate...
-
Influence of Additional Loads on Chosen Gait Parameters and Muscles Activity
PublikacjaThis paper is devoted to human motion analysis and comparison of chosen kinematics parameters during normal gait with and without additional load in a form of backpack. A stability in both cases were compared in both frontal and sagittal planes, by applying a video tracking system. Experimental tests performed on treadmill, passive markers, placed on volunteers bare skin were used. Additionally, an infra-red camera was employed...
-
A tool for designing water tanks for measuring hydroacoustic transducers
PublikacjaSpecial water tanks are commonly used to measure the parameters of underwater acoustic systems. They must meet specific requirements, the fulfilment of which ensures very small but acceptable measurement errors. These requirements define the size of the tank and its shape as well as the strong attenuation of reflected waves. At the design stage, it is necessary to determine the impact of the tank structure on the measurement errors...
-
Timber-frame house resistant to dynamic loads - analysis of wall panel filled with polyurethane foam
PublikacjaThe present study shows the experimentally and numerically determined response of a single timber-frame house wall panel filled with polyurethane (PU) foam under dynamic loads. The harmonic tests were conducted for the following frequencies: 0.5 Hz, 1.0 Hz, 2.0 Hz and 5.0 Hz for various values of the specified displacement. Based on the results of the comparison between the experimental tests and the numerical analyses, the numerical...