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1

Experimental study of nano-composite materials on vibration responses

Mobark Haidal Faisal Helal, Fahdel Essam Z., Hussein Mustafa Turki, Mohamad Barhm

Diagnostyka

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2023

|

Vol. 24, No. 3

art. no. 2023312

EN

This paper present of experimental and numerical study of nano Al2O3 cantilever beam for forced vibration, addressing an unexplored area in the existing literature. The proposed nano composite cantilever beam is modeled with hole and crack. The study is based on history loading calculation and composite morphology a global parameter, the transverse crack in nano composite cantilever beam was studied and analyzed experimentally using a four-channel dynamic signal acquisition (NI 9234) module for making high-accuracy measurements and its ideal for vibration applications. The relationship between the dispersion and interaction of the alumina nanoparticles within the cantilever beam and morphology of the solid, hole and crack composite has been identified. Furthermore, the influence of particles Al2O3 at different concentrations (0%, 1%, 3% and 4%) have been studied respectively. Supporting results proved that the crack and hole depth increases with increases of history loading. Nanoparticles dispersed within the specimen can increase energy dissipation during vibration, leading to improved damping characteristics. For future work, it is recommended to utilize statistical frequency domain input, such as Power Spectral Density (PSD), for assessing the structural response instead of employing time history loading.

2

Steel cantilever beam optimization with ANSYS software

Jaskot Anna

Zeszyty Naukowe Politechniki Częstochowskiej. Budownictwo

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2021

|

Z. 27 (177)

69-75

PL

Przedstawiono problem analizy złożonych konstrukcji stalowych w odniesieniu do badań analitycznych i numerycznych pojedynczego elementu konstrukcji. Celem było wykazanie zgodności obranych metod wyznaczania parametrów wytrzymałościowych belki wspornikowej oraz dobranie najlepszego przekroju poprzecznego w optymalizacji konstrukcji. Analitycznie oraz numerycznie wyznaczono strzałkę ugięcia belki oraz wartość maksymalnych naprężeń zredukowanych (wg Hubera von Misesa). Analizę numeryczną, z użyciem metody elementów skończonych, oraz optymalizację przeprowadzono w środowisku ANSYS. Na podstawie analizy statycznej konstrukcji przeprowadzono optymalizację masy belki poprzez zmianę jej wymiarów przekroju poprzecznego, przy uwzględnieniu wskazanych w pracy kryteriów optymalizacyjnych. W wyniku optymalizacji zostały wybrane rozwiązania spełniające wymagane kryteria. Masa konstrukcji została zmniejszona o połowę w porównaniu do wartości początkowych projektowanej konstrukcji. Dopuszczalne naprężenia nie zostały przekroczone.

EN

The problem of analysing complex steel structures in relation to analytical and numerical tests of a single structure element has been presented. The aim was t o demonstrate the compliance of the chosen methods for determining the strength parameters of a cantilever beam and to select the best cross-section for the optimization of the structure. The beam deflection and the value of the maximum reduced stresses (according to Huber von Mises’ hypothesis) have been determined numerically and analytically. Numerical analysis, on the basis of the finite element method, as well as the optimization, have been performed in the ANSYS environment. Based on the static analysis of the structure, optimization of the beam mass has been made by changing its cross-section dimensions, taking into account the specific optimization criteria, pointed in the work. As a result of optimization, solutions satisfying the required criteria have been selected. The weight of the structure has been reduced by half compared to the initial values of the designed structure. The permissible stresses have not been exceeded.

3

Instructions for the preparation of a numerical investigation on crack parameters of cantilever beam using FEA

Ansari M. A., Tiwari V. K.

Journal of Achievements in Materials and Manufacturing Engineering

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2021

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Vol. 109, nr 1

5--10

EN

Purpose: The operation of engineering structures may cause various type of damages like cracks, alterations. Such kind of defects can lead to change in vibration characteristics of cantilever beam. The superposition of frequency causes resonance leading to amplitude built up and failure of beam. The current research investigates the effect of crack dimensional parameters on vibrational characteristics of cantilever beam. Design/methodology/approach: The CAD design and FE simulation studies are conducted in ANSYS 20 simulation package. The natural frequencies, mode shapes and response surface plots are generated, and comparative studies are performed. The effect of crack dimensional parameters is then investigated using Taguchi Design of Experiments. The statistical method of central composite design (CCD) scheme in Response Surface Optimization is used to generated various design points based on variation of crack width and crack depth. Findings: The research findings have shown that crack depth or crack height have significant effect on magnitude of deformation and natural frequency. The deformation is minimum at 0.009 m crack height and reaches maximum value at 0.011 m crack height. Research limitations/implications: The crack induced in the cantilever beam needs to be repaired properly in order to avoid crack propagation due to resonance. The present study enabled to determine frequencies of external excitation which should be avoided. The limitation of current research is the type of crack studied which is transverse type. The effect of longitudinal cracks on vibration characteristics is not investigated. Practical implications: The study on mass participation factor has shown maximum value for torsional frequency which signifies that any external excitation along this direction should be avoided which could cause resonance and lead to amplitude build up. Originality/value: The beams are used in bridge girders and other civil structures which are continuously exposed to moist climate. The moisture present in the air causes corrosion which initiates crack. This crack propagates and alters the natural frequency of beam.

4

Performance-based Design and Construction of the “World Class” Gym in Minsk using Innovative Structural Solutions

Tur Andrei V., Tur Viktar V., Tsymbarevich Tsimafei A.

Modern Engineering

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2020

|

2

50--61

EN

The article presents the result of the implementation of innovative design solutions techniques during the construction of the building of the “WORLD CLASS” Fitness Club in Minsk with usage of the performance-based approach. Proposed design solution of building include the composite structures (plane frames consists of steel-concrete columns and delta-beam), prestressed hollow core slabs. The cantilever parts of the building were designed as a complex post-tensioned monolitic structure, including cantilever beams and slabs with a maximum length of 12 m, monolitic walls and pylons. The example of performance criteria verification (structural serviceability) with usage different methods presents.

5

A Fundamental Study on the Free Vibration of Geometrical Nonlinear Cantlever Beam using an Exact Solution and Experimental Investigation

Jamal-Omidi M., Shayanmehr M., Sazesh S.

Archive of Mechanical Engineering

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2018

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Vol. LXV, nr 1

65--82

EN

Two fundamental challenges in investigation of nonlinear behavior of cantilever beam are the reliability of developed theory in facing with the reality and selecting the proper assumptions for solving the theory-provided equation. In this study, one of the most applicable theory and assumption for analyzing the nonlinear behavior of the cantilever beam is examined analytically and experimentally. The theory is concerned with the slender inextensible cantilever beam with large deformation nonlinearity, and the assumption is using the first-mode discretization in dealing with the partial differential equation provided by the theory. In the analytical study, firstly the equation of motion is derived based on the theory of large deformable inextensible beam. Then, the partial differential equation of motion is discretized using the Galerkin method via the assumption of the first mode. An exact solution to the obtained nonlinear ordinary differential equation is developed, because the available semi analytical and approximated methods, due to their limitations, are not always sufficiently reliable. Finally, an experiment set-up is developed to measure the nonlinear frequency of oscillations of an aluminum beam within a domain of initial displacement. The results show that the proposed analytical method has excellent convergence with experimental data.

6

Interlaminar cracking resistance of nonhomogeneous composite beams

Dadej K., Bieniaś J., Surowska B.

Composites Theory and Practice

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2017

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R. 17, nr 3

144--148

EN

This article is devoted to interlaminar cracking research on carbon multidirectional fibrous-epoxy composites. Composite beams with 0°/0° 0°/45° and 0°/90° interfaces were subjected to double cantilever beam tests whereby force-crack opening displacement curves were determined. Additionally, crack length observations were conducted in order to determine the crack resistance curves of multidirectional composites. On the basis of the performed tests, it was found that the critical strain energy release rate for crack initiation is size independent of the material configuration. On the other hand, the fiber orientation is crucial to the critical strain energy release rate for crack propagation.

PL

Artykuł dotyczy badań odporności na pękanie wielokierunkowych kompozytów epoksydowo-włóknistych na bazie włókien węglowych. Belki kompozytowe z interfejsami 0°/0° 0°/45° oraz 0°/90° zostały zbadane za pomocą metody Double Cantilever Beam, w których wyznaczono charakterystyki siła - wielkość rozwarcia szczeliny. Dodatkowo prowadzono obserwacje długości pęknięcia w celu wyznaczenia krzywych odporności na pękanie kompozytów wielokierunkowych. Na podstawie przeprowadzonych badań stwierdzono, że wartość krytycznego współczynnika uwalniania energii dla inicjacji pęknięcia jest wielkością niezależną od ukierunkowania włókien. Natomiast ułożenie włókien jest kluczowe w przypadku krytycznego współczynnika uwalniana energii dla propagacji pęknięcia.

7

Modelling and testing of the piezoelectric beam as energy harvesting system

Koszewnik A., Wernio A.

Acta Mechanica et Automatica

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2016

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Vol. 10, no. 4

291--295

EN

The paper describes modelling and testing of the piezoelectric beam as energy harvesting system. The cantilever beam with two piezo-elements glued onto its surface is considered in the paper. As result of carried out modal analysis of the beam the natural frequencies and modes shapes are determined. The obtained results in the way mentioned above allow to estimate such location of the piezoactuator on the beam where the piezo generates maximal values of modal control forces. Experimental investigations carried out in the laboratory allow to verify results of natural frequencies obtained during simulation and also testing of the beam in order to obtain voltage from vibration with help of the piezo-harvester. The obtained values of voltage stored on the capacitor 𝐶0 shown that the best results are achieved for the beam excited to vibration with third natural frequency, but the worst results for the beam oscillating with the first natural frequency.

8

Experimental Observation Of Nonlinear Vibrations Using A Closed-Loop Vibration System

de Barros E., d’Andrade Souto C., Mathias M. H.

Metrology and Measurement Systems

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2015

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Vol. 22, nr 4

559--564

EN

This paper presents experimental observation of nonlinear vibrations in the response of a flexible cantilever beam to transverse harmonic base excitations around its flexural mode frequencies. In the experimental setup, instead of manual control of the signal excitation frequency and amplitude, a closed-loop vibration system is used to keep the excitation amplitude constant during the frequency sweep and to increase confidence in the experimental results. The experimental results show the presence of the third mode in the response when varying the excitation frequency around the fourth mode. The frequency-response curves, response spectrum and Poincaré plots were used for characterization of nonlinear dynamic behaviour of the beam.

9

Wpływ lokalizacji przyłożonego obciążenia na rozkład sił wewnętrznych w belce żelbetowej ze wspornikami krawędziowymi i o zredukowanej wysokości strefy przypodporowej

Stachoń T.

Materiały Budowlane

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2015

|

nr 10

86--88

PL

W belkach żelbetowych o złożonym kształcie przekroju poprzecznego zaobserwowano, że miejsce przyłożenia obciążenia ma wpływ na rozkład naprężeń w elemencie, a w szczególności w strefie przypodporowej. Potwierdzają to przeprowadzone analizy numeryczne i laboratoryjne badania elementów w skali naturalnej. Wykazano również przestrzenny charakter pracy konstrukcji i jej wpływ na rozkład naprężeń wewnętrznych.

EN

In reinforced concrete beams with complex cross-sectional shapes, it was observed that the location of load affects the distribution of stresses in the element and in particular support zone. This is confirmed numerical analysis and laboratory testing of elements in the natural scale. It was also shown the spatial nature of the work of construction and its impact on the distribution of internal stress.

10

Forced vibrations analysis of a cantilever beam using the vision method

Romaszko M., Sapiński B., Sioma A.

Journal of Theoretical and Applied Mechanics

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2015

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Vol. 53 nr 1

243--254

EN

This article presents an analysis of forced vibrations of a homogeneous cantilever beam using a vision method. Based on measurements, displacements of defined beam points have been determined as a function of time in directions perpendicular to and along the beam axis together with the trajectory of these points in the plane of the beam transverse vibrations. A model describing the displacement of the beam with a moving holder (kinematic excitation) is presented along with formulas defining motion of points in the plane of the beam transverse vibrations, which have been verified experimentally by recording beam vibrations using a specialised vision system.

11

Metodyka oceny uszkodzenia elementów konstrukcyjnych na przykładzie belki izotropowej jednostronnie utwierdzonej

Samborski S., Wieczorkiewicz J., Rusinek R., Dziedzic J.

Journal of Technology and Exploitation in Mechanical Engineering

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2015

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Vol. 1, nr 1-2

5--16

PL

W pracy zbudowano model numeryczny belki wspornikowej z uszkodzeniem i bez uszkodzenia oraz wyznaczono ichczęstości własne dla zadanych charakterystyk mate-riałowych. Następnie przeprowadzono badania na fizycznym obiekcie przy użyciu wibrometru laserowego PSV-500 firmy Polytec. Otrzymane rezultaty doświadczalne porównano z wynikami obliczeń nume-rycznych stosując metody analizy sygnału oparte na wykresach płaszczyzny fazowej.

EN

This paper focuses on analysis of damage detection cantilever beam. Finite Element Method was used to simulate vibrations of the intact and the damaged beams. Analysis of natural frequencies of both the intact and the damaged beams was performed in order to observe the effect of damage on the beams dynamics. Next, the phase diagrams technique was applied andfinally, experimental verification was performed to check the numerical results.

12

Badania stref przypodporowych żelbetowych belek wspornikowych

Stachoń T., Maj M., Ubysz A.

Materiały Budowlane

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2014

|

nr 6

68--69

PL

W żelbetowych belkach ze wspornikami, o przekroju odwróconej litery T, zaobserwowano wpływ obciążenia wsporników bocznych na rozkład naprężeń w strefie przypodporowej. Wyniki badań potwierdzają rozbieżności uzyskane z analizy porównawczej normowych modeli kratownicowych. Brak jest natomiast modelu kratownicowego uwzględniającego wpływ obciążenia bocznych wsporników.

EN

In reinforced concrete beams with brackets, with a cross section of an inverted T observed impact of load the side brackets on the stress distribution in the supports zone. The results confirm the differences obtained from the comparative analysis of code truss models. There is no, however truss model takes into account the effect of the load side brackets.

13

Simulation study of the non-collocated control of a cantilever beam

Tuma J., Mahdal M., Suranek P.

Mechanics and Control

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2013

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Vol. 32, no. 3

110--116

EN

This article deals with the simulation of the active vibration control of a cantilever beam. For these purposes, a lumped parameter model has been developed and the simplest controller has been designed to ensure the structural stability of the control loop. The controller is of a proportional velocity feedback type. The control loop can also be stable in the case of a very small inherent damping of the cantilever beam. The lumped-parameter model is based on the Euler-Bernoulli beam theory. The developed tools can be used to simulate the collocated and non-collocated active vibration control. Since this article is intended to study the behaviour of a non-collocated control system of the transducer is sensing the vibration of the free end of the beam, while the actuator force acts near the fixed end.

PL

Artykuł dotyczy symulacji aktywnego sterowania drganiami belki wspornikowej. W tym celu zaproponowano model o parametrach skupionych oraz najprostszy regulator, który zapewnia stabilność strukturalną. Zastosowano regulator proporcjonalny, z prędkościowym sprzężeniem zwrotnym. Pętla sterowania może być stabilna nawet w przypadku bardzo małego tłumienia drgań własnych belki. Model o parametrach skupionych został wyprowadzony na podstawie teorii Eulera-Bernoulliego. Zaproponowane podejście może zostać zastosowane do symulacji aktywnego sterowania drganiami w przypadku, gdy czujnik i element wykonawczy są umieszczone w tym samym miejscu bądź w różnych miejscach na belce. Ponieważ artykuł dotyczy badań własności aktywnego sterowania drganiami w drugim z tych przypadków,przetwornik pomiarowy drgań został umieszczony na swobodnym końcu belki, natomiast element wykonawczy działa na utwierdzonym końcu.

14

Semiactive damping of a three-layered cantilever beam with MR fluid embedded in its structure

Snamina J., Sapiński B., Romaszko M.

Vibrations in Physical Systems

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2012

|

Vol. 25

361--366

EN

The subject of the paper is vibration control of a cantilever beam with magnetorheological (MR) fluid. Based on the results of identification and energy analysis, a control algorithm for free vibrations damping of the beam was proposed. The algorithm was realized by controlling the current supplying the electromagnet. The free vibrations of beam were investigated for constant current and current varied according to the assumed control algorithm.

15

Analiza parametrów drgań wielokomorowych belek wspornikowych z cieczą magnetoreologiczną

Snamina J., Sapiński B., Romaszko M.

Modelowanie Inżynierskie

|

2012

|

T. 12, nr 43

247-254

PL

W pracy przeprowadzono analizę drgań swobodnych wielokomorowych belek wspornikowych z cieczą magnetoreologiczną (MR). Wyznaczono podstawową częstotliwość drgań własnych i bezwymiarowy współczynnik tłumienia belek na podstawie zarejestrowanych przemieszczeń swobodnego końca belek w polu magnetycznym oraz bez pola magnetycznego. Przeanalizowano wpływ natężenia pola magnetycznego na charakterystyki sztywności i tłumienia belek.

EN

The study presents the results of laboratory studies on free vibrations of sandwich cantilever beams with multiple magnetorheological (MR) segments. On the basis of collected data for each beam the natural freąuency and dimensionless damping coefficient were calculated. The influence of magnetic field strength and filling the right segment on stiffness and damping characteristics was analyzed.

16

The Influence of a Magnetic Field on Vibration Parameters of a Cantilever Sandwich Beam with Embedded MR Fluid

Sapiński B., Snamina J., Romaszko M.

Acta Mechanica et Automatica

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2012

|

Vol. 6, no. 1

53-56

EN

The paper investigates a magnetic field acting on a three-layer sandwich beam filled with MR fluid, the field being generated by an electromagnet. The FEM approach is applied to determine the magnetic field strength and magnetic flux density in the area between the poles and in the MR fluid layer. The results are utilised to establish the relationship between the magnetic flux density and parameters of the assumed model of the MR fluid layer.

17

Drgania układu mechatronicznego z uwzględnieniem ścinania warstwy łączącej

Buchacz A., Płaczek M.

Modelowanie Inżynierskie

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2008

|

T. 5, nr 36

335-342

PL

Praca dotyczy analizy drgań układu mechatronicznego w postaci belki wspornikowej oraz przytwierdzonego do jej powierzchni, za pomocą warstwy łączącej, przetwornika piezoelektrycznego. Układ ten obciążony jest siłą harmonicznie zmienną, działającą w kierunku prostopadłym do osi belki, przyłożoną na jej swobodnym końcu. Wyznaczono dynamiczne równania ruchu analizowanego układu z uwzględnieniem ścinania warstwy kleju, a także charakterystykę dynamiczną układu na podstawie przybliżonej metody Galerkina. Przebieg wyznaczonej podatności dynamicznej przedstawiono na wykresie.

EN

The paper presents analysis of flexural vibrating machatronic system. Considered system is compounded of cantilever bending beam and a strip-like piezoelectric transducer. The transducer is bonded on the beam surface by connection layer which has homogeneous properties on all its length. This mechatronic system is loaded with harmoniousness variable force operates perpendicular to the beam’s axis on the end of the beam. Beam’s vibrations affect piezoelectric transducer through the agency of connection layer which generates electric charge and produces additional stiffness. Dynamic equations of considered mechatronic system were assigned on the basis of elementary beam’s and transducer’s section dynamic equilibrium. Transducer’s dynamic equation was assigned using transducer’s piezoelectric properties. Dynamic characteristic of considered mechatronic system, including pure shear of the connection layer was assigned on the basis of approximate Galerkin’s method and illustrated on the chart with giving consideration to beam’s and transducer’s geometrical and material parameters.

18

Vibration control capabilities of a cantilever beam with a magnetorheological fluid

Sapiński B., Snamina J.

Mechanics / AGH University of Science and Technology

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2008

|

Vol. 27, no. 2

70-75

EN

This paper presents an analysis of dynamic characteristics of a cantilever beam with a magnetorheological (MR) fluid. The beam consists of two aluminium outer layers and MR fluid layer placed between them. Due to MR fluid control capabilities both damping and stiffness of the beam can be changed simultaneously. The simple model of three-layered structure is assumed. Vibration characteristics of the beam are predicted for various magnetic field strength and a simple control algorithm based on switching of the beam stiffness is proposed. The results of calculations illustrate the vibration control capabilities of the MR adaptive beam at various level of magnetic strength.

PL

W pracy przedstawiono analizę własności dynamicznych belki z cieczą magnetoreologiczną (MR). Belka składa się z trzech warstw. Dwie zewnętrzne warstwy wykonano z aluminium, a przestrzeń pomiędzy nimi wypełniono cieczą MR. Sztywność i tłumienność belki można zmieniać dzięki zależnym od pola magnetycznego własnościom cieczy. Do obliczeń przyjęto prosty model belki trójwarstwowej. Wyznaczono podstawowe charakterystyki dynamiczne belki dla różnych wartości natężenia pola magnetycznego. Otrzymane wyniki potwierdzają możliwości sterowania drganiami belek zawierających warstwę cieczy MR.

19

Modeling Impact of a Cantilever Beam

Kapitaniak T., Czołczyński K., Błażejczyk-Okolewska B.

Machine Dynamics Problems

|

2008

|

Vol. 32, No. 4

37-49

EN

A vibrating system with one degree of freedom that can be employed to predict a nature of motion with impacts of certain systems with heavy mass of elastic elements is subject to investigations. An example of such a system is a heavy cantilever beam with a mass impacting on the base, fixed at its end. The applicability limits of two ways of modelling impacts described as hard impacts and soft impacts, as well as advantages and disadvantages of both the ways have been presented below.

20

Modal analysis of vibrating structures impregnated with crack

Das H. C., Parhi D. R.

International Journal of Applied Mechanics and Engineering

|

2008

|

Vol. 13, no 3

639-652

EN

In the current investigation a dynamic analysis of the cracked cantilever beam is carried out. Local flexibility is being introduced due to the presence of a crack in the structural member that affects its dynamic response. For finding out the deviation in mode shapes and natural frequencies of the cracked cantilever beam the local stiffness matrices are taken into account. Theoretical expressions have been developed to calculate the natural frequencies and mode shapes of the cracked cantilever beam using local stiffness matrices. The strain energy release rate has been used for calculating the local stiffnesses of the beam. Suitable boundary conditions are taken into account at the crack location. Comparisons made between the numerical results and the corresponding experimental results show very good agreement and authenticate the theory developed.