Search results for: beam

In the paper a hybrid model of rotating beam is presented. It was obtained by using two methods: modal decomposition and spatial discretization. Reduced modal model was built for the system without the load related to inertia forces that occur during beam rotation. This inertia load was next modeled by using the method of simply spatial discretization and combined with reduced modal model. This approach allows to obtain accurate...

Full text available to download

Enriched buckling for beam-lattice metamaterials

Publication

V. Eremeev
E. Turco

- MECHANICS RESEARCH COMMUNICATIONS - Year 2020

We discuss two examples of beam-lattice metamaterials which show attractive mechanical properties concerning their enriched buckling. The first one considers pantographic beams and the nonlinear solution is traced out numerically on the base of a Hencky’s model and an algorithm based on Riks’ arc-length scheme. The second one concerns a beam-lattice with sliders and the nonlinear solution is discussed in analytic way and, finally,...

Full text available to download

Distorsional analysis of I-section beam

Publication

M. Kujawa

- TASK Quarterly - Year 2012

An elastic stiffness matrix was derived in the case of distortion of a restrained thin-walled I-section beam using the minimum total stationary elastic energy condition. The function describing the angle of distortion was adopted form the solution of differential equation in the case of restrained distortion. The example presented in the paper helps to assess the correctness of the proposed solution. The proposed elastic stiffness...

Full text available to download

Performance of CMS hadron calorimeter timing and synchronization using test beam, cosmic ray, and LHC beam data

Publication

C. Collaboration
R. S. Romaniuk

- Journal of Instrumentation - Year 2010

Full text to download in external service

Energy efficient beam control for 5G antennas

Publication

- Year 2024

The rapid development of 5G and beyond systems demands improvement in communication speed, latency and safety to maintain the required quality of service. This paper presents an overview of different concepts of energy-efficient antenna systems, which offer beam-shaping and beam-steering functionalities, that enhance connectivity performance and can be used in 5G applications. Different designs for 5.9 GHz, 39 GHz and 60 GHz frequency...

Full text to download in external service

GPR simulations for diagnostics of a reinforced concrete beam

Publication

- Year 2016

The most popular technique for modelling of an electromagnetic field, the finite difference time domain (FDTD) method, has recently become a popular technique as an interpretation tool for ground penetrating radar (GPR) measurements. The aim of this study is to detect the size and the position of damage in a reinforced concrete beam using GPR maps. Numerical simulations were carried out using the finite differ-ence time domain...

The effect of mechanical coupling on the beam pattern of a multielementarray

Publication

A. Elminowicz
W. Lis
Z. Wojan

- ACTA ACUSTICA UNITED WITH ACUSTICA - Year 2002

W artykule opisano nową metodę redukcji listków bocznych hydroakustycznej anteny wieloelementowej. Wykorzystano tu efekt ważenia amplitud sygnałów odbieranych przez poszczególne elementy poprzez kontrolowane ich mechaniczne sprzężenie. Opisane zostały wyniki badań kilku modeli anten zbudowanych z pięciu elementów. Wyniki badań zostały zweryfikowane obliczeniami symulacyjnymi. Stwierdzono, zarówno na drodze eksperymentalnej jak...

Crack identification in cantilever beam using wavelets

Publication

- Year 2003

Przedstawiono metodę identyfikacji zniszczeń przy użyciu transformacji falkowej. Rozpatrzono przykład belki wspornikowej. Pokazano, że transformacja falkowa wykrywa miejsce zniszczenia.

Damage Detection of Steel-Concrete Composite Beam

Publication

M. Szumigała
A. Pełka-Sawenko
T. Wróblewski
M. Abramowicz

- Civil and Environmental Engineering Reports - Year 2018

Full text to download in external service

A three-dimensional periodic beam for vibroacoustic isolation purposes

Publication

- MECHANICAL SYSTEMS AND SIGNAL PROCESSING - Year 2019

This paper presents results of investigations on a three-dimensional (3-D) isotropic periodic beam. The beam can represent a vibroacoustic isolator of optimised dynamic characteristics in the case of its longitudinal, flexural and torsional behaviour. The optimisation process concerned both the widths as well as the positions of particular frequency band gaps that are present in the frequency spectrum of the beam. Since the dynamic...

Full text available to download

Azimuth estimator for a rotating array radar with wide beam

Publication

- Year 2017

The problem of estimating azimuth in rotating array radar with a beam, wide in the azimuth plane, is considered. Under such setup the echo signal usually has a very low signal to noise ratio, but the number of observations is large, because of long dwell times. The proposed solution is based on the maximum likelihood approach, but it employs simplifications which facilitate its implementation in real time systems. Results, obtained...

Full text to download in external service

Split-Beam Echosounder Data from Puck Bay

Publication

P. Pezacki

- Year 2022

The acoustic data was collected in 2018–2019 in the Bay of Puck in the seasons: autumn, winter, spring. The data was collected during the day and night using three split-beam echosounders with frequencies of 38 kHz, 120 kHz and 333 kHz at a designated study area not far from the city of Hel, while the ship was sailing. To ensure data quality, the echosounders were calibrated and passive noise was measured.

Full text available to download

Pressure distribution and beam pattern of the parametric acoustic arrays.

Publication

A. Baranowska

- Year 2004

Przedstawiono model matematyczny i wyniki badań teoretycznych zjawiska oddziaływań fal dla źródeł parametrycznych. Model matematyczny zbudowano w oparciu o równanie KZK. Do rozwiązania zagadnienia zastosowano metodę różnic skończonych. Badano zmiany ciśnienia fal wybranych częstotliwości w obrębie wiązki akustycznej oraz charakterystyki kierunkowe dla kołowych źródeł parametrycznych generujących fale różnych częstotliwości.

VRML visualization of pelagic fish movement in the echosounder beam.

Publication

- HYDROACOUSTICS - Year 2003

Przedstawiono konstrukcję dynamicznych trójwymiarowych echogramów dla danych pochodzących z przeszukiwań akustycznych zrealizowanych przy pomocy echosondy z rozszczepioną wiązką. Wizualizację zrealizowano wykorzystując język opisu wirtualnej rzeczywistości VRML.

Flexural shera wave propagation in cracked composite beam.

Publication

M. Krawczuk
M. Palacz
W. Ostachowicz

- Year 2004

W pracy przedstawiono model i wyniki analizy wpływu peknięcia na propagacje fali gietno-scinajacej w belce kompozytowej.

Genetic algorithm for fatique crack detection in Timoshenko beam.

Publication

M. Krawczuk

- Year 2004

W pracy przedstawiono metodę detekcji peknięć zmęczeniowych w początkowej fazie ich rozwoju. Algorytm detekcji wykorzystuje metodę algorytmów genetycznych połączoną z metodą gradientową. Funkcja celu oparta została o zmiany w propagujacej fali sprężystej.

4-Point beam tensile test on a soft adhesive

Publication

M. Budzik
J. Jumel
M. Shanahan

- MATERIALS & DESIGN - Year 2013

An adhesive butt joint with a soft bondline has been studied. A series of experiments was conducted on test pieces constituted of aluminium adherends bonded with a low modulus epoxy adhesive, ScotchWeld™ 2216. The joint was subjected to four point bending, in tension/compression loading, under constant deflection rate, with the bondline being parallel to the applied load. The objective was to examine and evaluate crack nucleation...

Full text to download in external service

TB11 test for short w-beam road barrier

Publication

- Year 2017

FEM (Finite Element Method) is well-suited and widely used tool for simulating a range of phenomena: from these with simple and static behaviour, up to those complicated, highly nonlinear and involving many contacts. In present paper we use one of the advantages of FEM: parametric study could be easily performed and is more economical than series of in-situ tests. If recommended practices is carefully followed, results obtained...

Full text available to download

Modelling and analysis of beam/bar structure by application of bond graphs

Publication

- Journal of Theoretical and Applied Mechanics - Year 2011

The paper presents an uniform, port-based approach to modelling of beam/bar systems (trusses). Port-based model of such distributed parameter system has been defined by application of the bond graph methodology and the distributed transfer function method (DTFM). The proposed method of modelling enables to formulate input data for computer analysis by application of the DTFM. The constructed computational package enables the frequency...

Full text available to download

About Unusual Diffraction and Thermal Self-Action of Magnetosonic Beam

Publication

A. Perelomova

- Archives of Acoustics - Year 2022

The dynamics of slightly diverging two-dimensional beams whose direction forms a constant angle θ with the equilibrium straight magnetic strength is considered. The approximate dispersion relations and corresponding links which specify hydrodynamic perturbations in confined beams are derived. The study is dedicated to the diffraction of a magnetosonic beam and nonlinear thermal self-action of a beam in a thermoconducting gaseous plasma....

Full text available to download

Experimental and numerical analysis of an aluminum cantilevered beam with polymer adhesive

Publication

- Procedia Engineering - Year 2017

In this paper, experimental and numerical investigation on a composite cantilevered aluminum beam has been conducted. The subject of the study consists of two plain aluminum elements bonded with polymer adhesive of different thickness. It has been proven in the previous study that this kind of material has high damping properties. During an experimental investigation, value of damping ratios have been obtained. The aim of a numerical...

Full text available to download

Modelling of the Heat Flux Density Distribution for Laser Beam Welding

Publication

- Solid State Phenomena - Year 2011

Great interest of the laser beam welding in industry is a new theoretical task, making planning the welding procedure specification and the quality control of welded joints easier. Estimating and calculating the dimensions of a weld pool and temperature distribution near weld mainly concern heat source modelling. In the presented work calculations of welding pool shape and thermal field for cylindrical-powered-normally model of...

Full text to download in external service

Highly porous nanoberyllium for X-ray beam speckle suppression

Publication

A. Goikhman
I. Lyatun
P. Ershov
I. Snigireva
P. Wojda
V. Gorlevsky
A. Semenov
M. Sheverdyaev
V. Koletskiy
A. Snigirev

- JOURNAL OF SYNCHROTRON RADIATION - Year 2015

The speckle suppressor device containing highly porous nanoberyllium is proposed for manipulating with the spatial coherence length and removing undesirable speckle structure during the imaging experiments. We report a special device called the speckle suppressor, which contains the highly porous nanoberyllium plate, compacted from both sides by two beryllium windows. By insertion the speckle suppressor in the X-ray beam it allows...

Full text available to download

NONLINEAR VIBRATION ANALYSIS OF BEAM AND PLATE WITH CLOSED CRACK: A REVIEW

Publication

- Acta Mechanica et Automatica - Year 2022

The effect of nonlinearity is high sensitivity in damage detection, especially for closed cracks and delamination. This review illustrates the results of several researchers dealing with nonlinear effects caused by the closure of cracks in the structure, i.e., beam and plate structures. Early detection of damage is an important aspect for the structure and, therefore, continuous progress is being made in developing new and effective...

Full text available to download

A novel approach to bottom scattering using a narrow acoustic beam.

Publication

A. Zieliński
J. Tęgowski
Z. Łubniewski
J. Demkowicz

- Year 2004

Przedstawiono model opisujący w prosty sposób rozpraszanie sygnału akustycznego na dnie morskim jako filtr liniowy z odpowiedzią impulsową o zmieniającej się w czasie chwilowej dominującej częstotliwości. Przedyskutowano pasujący do tego modelu przypadek zbioru punktowych rozpraszaczy równomiernie rozmieszczonych na powierzchni dna, w tym wpływ takich parametrów jak głębokość oraz odległość pomiędzy rozpraszaczami.

The dynamic analysisi of cracked Thimoshenko beam by the spectral element method.

Publication

M. Krawczuk
M. Palacz
W. Ostachowicz

- JOURNAL OF SOUND AND VIBRATION - Year 2003

W pracy przedstawiono model belli Timoshenko z pęknięciem poprzecznym oparty o metodę elementów spektralnych. Przedstawiono wyniki propagacji fali sprężystej i jej interakcję z pęknięciem.

Estimation of the parameters of the discrete model of a steel–concrete composite beam

Publication

T. Wróblewski
S. Berczyński
M. Abramowicz
T. Wróblewski

- Archives of Civil and Mechanical Engineering - Year 2013

Full text to download in external service

3D Imaging Of Underwater Objects Using Multi-Beam Data

Publication

- HYDROACOUSTICS - Year 2014

One of the main applications of multibeam sonars is high resolution bathymetry measurement, as well as detecting and imaging of underwater objects like shipwrecks. In order to obtain the visualisation quality good enough to allow the researcher to investigate an object in more detail, the approach relying on construction of three-dimensional model of an imaged object, e.g. consisting of nodes, edges and plane elements (facets)...

Full text available to download

Cavitation Erosion Resistance of Austenitic Microstructure Created byLaser Beam

Publication

M. Szkodo

- Solid State Phenomena - Year 2010

Praca przedstawia własności kawitacyjne różnych mikfrostruktur austenitycznych tworzonych za pomocą wiązki lasera na stalach X5CrNi18-10 oraz C45. Stal X5CrNi18-10 była laserowo stopowana węglikiem TiC oraz stopowana Ni, Mn, Cr i Nb. Jako żródło mocy stosowany był laser CO2. Własności kawitacyjne oceniane były na stanowisku z wirującą tarczą. Badania ujawniły różną podatność struktury austenicycznej do odkształceń plastycznych...

Analysis of beam sharpening effectiveness in broadband radar on inland waters

Publication

W. Kazimierski
A. Stateczny

- Year 2015

Full text to download in external service

On effective properties of beam-lattice structures made of flexoelectric materials

Publication

M. Malikan
V. Eremeev
J. Ganghoffer

- Year 2020

The e-Workshop Advances in ELAstoDYNamics of architected materials and BIOmaterials International Research Project (IRP) Coss&Vita of the CNRS

Proteomic Analysis of Proton Beam Irradiated Human Melanoma Cells

Publication

S. Kedracka-Krok
U. Jankowska
M. Elas
U. Sowa
J. Swakon
A. Cierniak
P. Olko
B. Romanowska-Dixon
K. Urbanska

- PLOS ONE - Year 2014

Full text to download in external service

The dynamic analysis of a cracked Timoshenko beam by the spectral element method

Publication

M. Krawczuk
M. Palacz
W. Ostachowicz

- JOURNAL OF SOUND AND VIBRATION - Year 2003

Full text to download in external service

Vibration and buckling characteristics of nonlocal beam placed in a magnetic field embedded in Winkler–Pasternak elastic foundation using a new refined beam theory: an analytical approach

Publication

S. Kumar Subrat
S. Chakraverty
M. Malikan

- European Physical Journal Plus - Year 2020

In this article, a new refined beam theory, namely one variable first-order shear deformation theory, has been employed to study the vibration and buckling characteristics of nonlocal beam. The beam is exposed to an axial magnetic field and embedded in Winkler–Pasternak foundation. The von Kármán hypothesis along with Hamilton’s principle has been implemented to derive the governing equations for both the vibration and buckling...

Full text available to download

Thermal self-action effects of acoustic beam in a vibrationally relaxing gas

Publication

A. Perelomova

- APPLIED MATHEMATICAL MODELLING - Year 2014

Thermal self-action of acoustic beam in a molecular gas with excited internal degrees of molecules’ freedom, is studied. This kind of thermal self-action differs from that in a Newtonian fluid. Heating or cooling of a medium takes place due to transfer of internal vibrational energy. Equilibrium and non-equilibrium gases, which may be acoustically active, are considered. A beam in an acoustically active gas is self-focusing unlike...

Full text available to download

Direction-of-Arrival Estimation Using an ESPAR Antenna with Simplified Beam Steering

Publication

Ł. Kulas

- Year 2017

In this paper, it has been shown, how electronically steerable parasitic array radiator (ESPAR) antenna, in which beam steering is done in a simple way, can be used for directionof- arrival (DoA) estimation of an unknown signal impinging the antenna. The concept is based on an ESPAR antenna having twelve parasitic elements, in which beam switching is realized by RF switches providing required loads to its parasitic elements. Numerical...

Two-Row ESPAR Antenna with Simple Elevation and Azimuth Beam Switching

Publication

- IEEE Antennas and Wireless Propagation Letters - Year 2021

In this letter, we propose a two-row electronically steerable parasitic array radiator (ESPAR) antenna designed for direction of arrival (DoA) estimation in Internet of Things (IoT) applications relying on simple microcontrollers. The antenna is capable of elevation and azimuth beam switching using a simple microcontroller-oriented steering circuit and provides 18 directional radiation patterns, which can be grouped in 3 distinctive...

Full text available to download

Detection of Closing Crack in Beam Based on Responses Induced by Harmonic Excitation

Publication

- SENSORS - Year 2024

The non-linear contact model was chosen to simulate the closed crack in the cantilever beam. The study examines the shape and characteristics of the phase diagram of a cantilever beam with closed cracks. It investigates how various crack properties influence the geometry of the phase diagram and proposes a method for identifying cracks based on their features. The area of each closed curve in the phase diagram is determined using...

Full text available to download

Retrofit analysis of florida beam-and-post reinforced concreta bridge barriers

Publication

J. W. Wekezer
I. Kreja
M. Issa

- Engineering Transactions - Year 2002

Tematem pracy jest analiza przebiegu kolizji drogowych w przypadku najechania rozpędzonego pojazdu na betonową barierę mostową typu "Florida beam-and-post". Przedstawiono podstawy konstruowania modelu obliczeniowego do komputerowej symulacji zderzenia przy wykorzystaniu systemu LS-Dyna. Na podstawie otrzymanych wyników sformułowano zalecenia ewentualnych modyfikacji istniejących barier w celu poprawienia ich własności.

Full text available to download

On existence and uniqueness of weak solutions for linear pantographic beam lattices models

Publication

V. Eremeev
F. S. Alzahrani
A. Cazzani
F. Dell’isola
T. Hayat
E. Turco
V. Konopińska-Zmysłowska

- CONTINUUM MECHANICS AND THERMODYNAMICS - Year 2019

In this paper, we discuss well-posedness of the boundary-value problems arising in some “gradientincomplete” strain-gradient elasticity models, which appear in the study of homogenized models for a large class ofmetamaterials whosemicrostructures can be regarded as beam lattices constrained with internal pivots. We use the attribute “gradient-incomplete” strain-gradient elasticity for a model in which the considered strain energy...

Full text available to download

Numerical simulation of a thin-walled beam with warping stiffeners undergoing torsion

Publication

- TASK Quarterly - Year 2002

W pracy rozwinięto koncepcję zastosowania superelementów węzłowych do modelowania stężeń konstrukcyjnych w belkach cienkościennych. Przeprowadzono analizę pracy belek cienkościennych o bisymetrycznym przekroju otwartym ze stężeniami bimomentowymi w formie przepon i przewiązek.

Full text available to download

Experimental an numerical investigation of wave propagation in composite beam with an additional mass

Publication

W. Ostachowicz
M. Krawczuk
M. Palacz

- Year 2005

W pracy przedstawiono wyniki badań eksperymentalnych i symulacji numerycznych ilustrujace wpływ dodatkowej masy na propagacje fali Lamba w belce kompozytowej.