Structural damage mitigation using a fuzzy controller

In this paper, a novel approach for detecting crack location and its intensity in cantilever beam by Fuzzy logic techniques is established. The analysis has been done by using ANSYS FE software. The fuzzy controller with Bell shaped membership functions are used here which consists of three input parameters are relative deviation of first three natural frequencies and two output parameters are relative crack depth and relative crack location respectively. A series of fuzzy rules are resulting from vibration parameters which are finally used for prediction of crack location and its intensity. This method provides the knowledge towards the detection, location and characterization of the damage in the cantilever beam.

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Semi-active seismic control of an 11-DOF building model with TMD+MR damper using type-1 and -2 fuzzy algorithms

Journal of Vibration and Control ◽

10.1177/1077546317696369 ◽

2017 ◽

Vol 24 (13) ◽

pp. 2938-2953 ◽

Cited By ~ 22

Author(s):

Akbar Bathaei ◽

Seyed Mehdi Zahrai ◽

Meysam Ramezani

Keyword(s):

Active Control ◽

Structural Damage ◽

Structural Control ◽

Passive Control ◽

Fuzzy Controller ◽

Mr Damper ◽

Control Force ◽

Building Model

Nowadays, vibration control of structures is considered as a challenging field among scientists and engineers. Structural damage and financial losses due to recent earthquakes in different countries have more than ever before accentuated the importance of controlling earthquake-induced vibrations. In recent years, semi-active control has been introduced as an efficient and reliable type of structural control which provides the reliability of passive control and flexibility of active control systems at the same time. In this study, the performance of a semi-active tuned mass damper (TMD) with adaptive magnetorheological (MR) damper is investigated using type-1 and -2 fuzzy controllers for seismic vibration mitigation of an 11-degree of freedom building model. The TMD is installed on the roof and the MR damper is located on the 11th story. The MR damper has a capacity of producing a 1000 kN control force. The fuzzy system is designed based on the acceleration and velocity of the top floor determining the input voltage needed to produce the control force based on accelerating or decelerating movements of structure. The seismic performance of semi-active type-2 controller, which considers the uncertainties related to input variables, is higher than that of the type-1 fuzzy controller. The type-2 fuzzy controller is capable of reducing further the maximum displacement, acceleration, and base shear of the structure by 11.7, 14, and 11.2%, respectively, compared to the type-1 fuzzy controller.

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Partial eigenvalue assignment for structural damage mitigation

Journal of Sound and Vibration ◽

10.1016/j.jsv.2010.08.024 ◽

2011 ◽

Vol 330 (1) ◽

pp. 9-16 ◽

Cited By ~ 14

Author(s):

Chimpalthradi R. Ashokkumar ◽

N.G.R. Iyengar

Keyword(s):

Structural Damage ◽

Damage Mitigation ◽

Eigenvalue Assignment

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Vibration control for structural damage mitigation

Journal of Vibration and Control ◽

10.1177/1077546313519283 ◽

2014 ◽

Vol 21 (15) ◽

pp. 2995-3006 ◽

Cited By ~ 5

Author(s):

Chimpalthradi R Ashokkumar

Keyword(s):

Vibration Control ◽

Structural Damage ◽

Damage Mitigation

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Evaluation of single-electron movies of glutamine synthetase molecules

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100075191 ◽

1983 ◽

Vol 41 ◽

pp. 280-281

Author(s):

W. Kunath ◽

E. Zeitler ◽

M. Kessel

Keyword(s):

Electron Microscope ◽

Glutamine Synthetase ◽

Electron Irradiation ◽

Structural Damage ◽

Structural Changes ◽

Single Electron ◽

Continuous Series ◽

Digital Recording ◽

Recording Device ◽

Low Exposure

The features of digital recording of a continuous series (movie) of singleelectron TV frames are reported. The technique is used to investigate structural changes in negatively stained glutamine synthetase molecules (GS) during electron irradiation and, as an ultimate goal, to look for the molecules' “undamaged” structure, say, after a 1 e/Å2 dose.The TV frame of fig. la shows an image of 5 glutamine synthetase molecules exposed to 1/150 e/Å2. Every single electron is recorded as a unit signal in a 256 ×256 field. The extremely low exposure of a single TV frame as dictated by the single-electron recording device including the electron microscope requires accumulation of 150 TV frames into one frame (fig. lb) thus achieving a reasonable compromise between the conflicting aspects of exposure time per frame of 3 sec. vs. object drift of less than 1 Å, and exposure per frame of 1 e/Å2 vs. rate of structural damage.

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Temperature Dependence of the Critical Electron Dose for Fatty Acid Monolayers

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100053188 ◽

1982 ◽

Vol 40 ◽

pp. 78-79

Author(s):

Kenneth H. Downing ◽

Robert M. Glaeser

Keyword(s):

Electron Beam ◽

Fatty Acid ◽

Inelastic Scattering ◽

Temperature Dependence ◽

Structural Damage ◽

Direct Result ◽

Second Step ◽

Strong Temperature Dependence ◽

Electron Dose ◽

Covalent Bonds

The structural damage of molecules irradiated by electrons is generally considered to occur in two steps. The direct result of inelastic scattering events is the disruption of covalent bonds. Following changes in bond structure, movement of the constituent atoms produces permanent distortions of the molecules. Since at least the second step should show a strong temperature dependence, it was to be expected that cooling a specimen should extend its lifetime in the electron beam. This result has been found in a large number of experiments, but the degree to which cooling the specimen enhances its resistance to radiation damage has been found to vary widely with specimen types.

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Modification of the Electron Microscope for Investigation of Fully Hydrated Biological Specimens

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100064001 ◽

1969 ◽

Vol 27 ◽

pp. 418-419 ◽

Cited By ~ 2

Author(s):

R. C. Moretz ◽

D. F. Parsons

Keyword(s):

Electron Beam ◽

Electron Microscope ◽

Structural Damage ◽

Lower Percentage ◽

Vacuum Drying ◽

Total Removal ◽

Total Absence ◽

Biological Studies ◽

Electron Microscopes ◽

Beam Damage

Short lifetime or total absence of electron diffraction of ordered biological specimens is an indication that the specimen undergoes extensive molecular structural damage in the electron microscope. The specimen damage is due to the interaction of the electron beam (40-100 kV) with the specimen and the total removal of water from the structure by vacuum drying. The lower percentage of inelastic scattering at 1 MeV makes it possible to minimize the beam damage to the specimen. The elimination of vacuum drying by modification of the electron microscope is expected to allow more meaningful investigations of biological specimens at 100 kV until 1 MeV electron microscopes become more readily available. One modification, two-film microchambers, has been explored for both biological and non-biological studies.

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Slow-scan CCD cameras and low-dose High-Resolution Electron Microscopy: Direct and quantitative

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100169791 ◽

1994 ◽

Vol 52 ◽

pp. 412-413

Author(s):

M. Pan

Keyword(s):

Electron Microscopy ◽

High Resolution ◽

Structural Damage ◽

Low Dose ◽

Dynamic Range ◽

High Resolution Electron Microscopy ◽

Operating Conditions ◽

Digital Data ◽

Ccd Cameras ◽

Resolution Electron

It has been known for many years that materials such as zeolites, polymers, and biological specimens have crystalline structures that are vulnerable to electron beam irradiation. This radiation damage severely restrains the use of high resolution electron microscopy (HREM). As a result, structural characterization of these materials using HREM techniques becomes difficult and challenging. The emergence of slow-scan CCD cameras in recent years has made it possible to record high resolution (∽2Å) structural images with low beam intensity before any apparent structural damage occurs. Among the many ideal properties of slow-scan CCD cameras, the low readout noise and digital recording allow for low-dose HREM to be carried out in an efficient and quantitative way. For example, the image quality (or resolution) can be readily evaluated on-line at the microscope and this information can then be used to optimize the operating conditions, thus ensuring that high quality images are recorded. Since slow-scan CCD cameras output (undistorted) digital data within the large dynamic range (103-104), they are ideal for quantitative electron diffraction and microscopy.

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