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This document summarizes a student's experiment using a rebound hammer to non-destructively test the compressive strength of a concrete sample. The student took 10 readings from the concrete sample using the rebound hammer and averaged them. Based on the average rebound number and the rebound hammer test graph correlating rebound number to compressive strength, the student concluded that the compressive strength of the concrete sample was approximately 1500 psi or 10.3 MPa. Non-destructive testing allows evaluation of materials without damage and is used for quality control and reliability testing during use.
Application of non destructive test for structural health monitoring - state ...eSAT Journals
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Abstract
The concept of non-destructive testing (NDT) is to obtain material properties âin placeâ specimens without the destruction of the specimens and to do the structural health monitoring. NDT using Rebound hammer, Ultra pulse velocity, Half-cell potential, core cutter, carbonation depth, rebar locator, Rapid chloride penetration test, electric resistivity meter test and vibration base analysis by data analoger are very popular and highly effective in conducting structural health monitoring. The structure can be investigated by using a visual inspection, NDT, laboratory and field test performance. In this article a review of these tests have been provided to conduct effective structural health monitoring of a RCC structure
Keywords: Non-destructive test, visual inspection, corrosion, compressive strength
This document provides an overview of non-destructive testing (NDT) methods. It defines NDT as testing methods used to evaluate a part or material without impairing its future usefulness. The document then describes several common NDT techniques including visual testing, liquid penetrant testing, magnetic particle testing, eddy current testing, radiographic testing, acoustic emission testing, leak testing, infrared thermal testing, and ultrasonic testing. It provides details on the principles and applications of these various techniques. The document aims to classify NDT methods and standards as well as discuss the history and physics of ultrasonic testing.
This presentation describes 6 methods to check concrete sample by performing non destructive testing.
1. Rebound hammer
2. Dye penetration test
3. Pull out test for concrete
4.Half cell potentiometer test
5.Rebar scanner
6 ultrasonic pulse velocity test
NDT-Nondestructive testing is the process of inspecting, testing, or evaluating materials, components or assemblies for discontinuities, or differences in characteristics without destroying the serviceability of the part or system. In other words, when the inspection or test is completed the part can still be used.
Monitoring of concrete structures by electro mechanical impedance technique IEI GSC
Â
By Dr. S.N.Khante Associate Professor & Bhagyashri Sangai
at 31st National Convention of Civil Engineers
organised by
Gujarat State Center, The Institution of Engineers (India) at Ahmedabad
Seminar report on Non Destructive TestingSakshyam Rai
Â
This document provides a summary of non-destructive testing (NDT) methods. It discusses various NDT techniques such as visual inspection, dye penetration testing, magnetic particle inspection, and ultrasonic testing. For each method, it explains the basic principles, testing procedures, advantages, and limitations. The document is a report submitted by a student to their professor on the topic of NDT, as indicated by the title and introduction. It aims to inform the reader about common NDT approaches through detailed descriptions of select techniques.
This document summarizes a student's experiment using a rebound hammer to non-destructively test the compressive strength of a concrete sample. The student took 10 readings from the concrete sample using the rebound hammer and averaged them. Based on the average rebound number and the rebound hammer test graph correlating rebound number to compressive strength, the student concluded that the compressive strength of the concrete sample was approximately 1500 psi or 10.3 MPa. Non-destructive testing allows evaluation of materials without damage and is used for quality control and reliability testing during use.
Application of non destructive test for structural health monitoring - state ...eSAT Journals
Â
Abstract
The concept of non-destructive testing (NDT) is to obtain material properties âin placeâ specimens without the destruction of the specimens and to do the structural health monitoring. NDT using Rebound hammer, Ultra pulse velocity, Half-cell potential, core cutter, carbonation depth, rebar locator, Rapid chloride penetration test, electric resistivity meter test and vibration base analysis by data analoger are very popular and highly effective in conducting structural health monitoring. The structure can be investigated by using a visual inspection, NDT, laboratory and field test performance. In this article a review of these tests have been provided to conduct effective structural health monitoring of a RCC structure
Keywords: Non-destructive test, visual inspection, corrosion, compressive strength
This document provides an overview of non-destructive testing (NDT) methods. It defines NDT as testing methods used to evaluate a part or material without impairing its future usefulness. The document then describes several common NDT techniques including visual testing, liquid penetrant testing, magnetic particle testing, eddy current testing, radiographic testing, acoustic emission testing, leak testing, infrared thermal testing, and ultrasonic testing. It provides details on the principles and applications of these various techniques. The document aims to classify NDT methods and standards as well as discuss the history and physics of ultrasonic testing.
This presentation describes 6 methods to check concrete sample by performing non destructive testing.
1. Rebound hammer
2. Dye penetration test
3. Pull out test for concrete
4.Half cell potentiometer test
5.Rebar scanner
6 ultrasonic pulse velocity test
NDT-Nondestructive testing is the process of inspecting, testing, or evaluating materials, components or assemblies for discontinuities, or differences in characteristics without destroying the serviceability of the part or system. In other words, when the inspection or test is completed the part can still be used.
Monitoring of concrete structures by electro mechanical impedance technique IEI GSC
Â
By Dr. S.N.Khante Associate Professor & Bhagyashri Sangai
at 31st National Convention of Civil Engineers
organised by
Gujarat State Center, The Institution of Engineers (India) at Ahmedabad
Seminar report on Non Destructive TestingSakshyam Rai
Â
This document provides a summary of non-destructive testing (NDT) methods. It discusses various NDT techniques such as visual inspection, dye penetration testing, magnetic particle inspection, and ultrasonic testing. For each method, it explains the basic principles, testing procedures, advantages, and limitations. The document is a report submitted by a student to their professor on the topic of NDT, as indicated by the title and introduction. It aims to inform the reader about common NDT approaches through detailed descriptions of select techniques.
Operational Modal Analysis Implementation on a Hybrd Composite PlateHazira Haidzir
Â
This document discusses modal analysis techniques for predicting structural deformation in aerospace structures due to airflow. It compares experimental modal analysis (EMA), which uses artificial excitation, to operational modal analysis (OMA), which extracts modal properties from operational response only. The study implemented OMA on a composite plate using a laser vibrometer for contactless response measurement. OMA results matched an EMA analysis using impact testing, validating the technique. OMA avoids complex artificial excitation and represents actual operating conditions.
This document summarizes research on using magneto-optic imaging for non-destructive testing of metal structures. It describes developing new thin-film sensors with improved sensitivity, integrating the sensors and image recognition algorithms into a portable system, and applying a neural network algorithm called SONON to enhance defect detection in images. Laboratory experiments demonstrated the new sensors could detect smaller defects than previous methods. The overall aim is more accurate, automated inspections using portable, wearable equipment.
This document discusses a novel magneto-optic sensor called the MODE sensor that can be used for non-destructive testing of structural integrity. The MODE sensor uses thin films made of rare earth and transition metal oxides that have high magneto-optic properties, allowing it to detect cracks, fissures, and corrosion in structures. A portable system has been designed using this sensor to allow real-time inspection of bridges, fuel tanks, and other metal structures. The system includes image processing and pattern recognition capabilities to help identify defects.
The document provides an introduction to nondestructive testing (NDT). It defines NDT as inspecting or testing materials without destroying them to find defects. NDT is used across many industries to inspect equipment and ensure safety. Common NDT methods described include visual testing, liquid penetrant testing, magnetic particle testing, ultrasonic testing, electromagnetic testing, radiographic testing, and acoustic emission testing. NDT can be used at all stages of production and equipment lifecycles to detect flaws and ensure quality and integrity.
This document discusses non-destructive testing methods for evaluating materials. It describes several common non-destructive testing techniques such as liquid penetrant inspection, magnetic particle testing, ultrasonic testing, x-ray testing, and visual inspection. These techniques are used to inspect materials for defects without damaging the material. The document also discusses the importance of non-destructive testing for safety, reliability, and cost savings for manufacturers.
Introduction to the non destructive testing explains the methods for evaluating and verifying many types of Materials as plastics, structures, metals, chemicals, leakage, physical properties. It's very used in the concrete engineering world and in the scientific world.
This document discusses using fiber optic sensors with polydimethylsiloxane coatings for structural health monitoring of concrete structures. It aims to develop an affordable monitoring strategy for alkali-aggregate reaction and corrosion detection. The strategy involves a heterogeneous multi-sensor data fusion system using acoustic, electro-mechanical, optical and embedded sensors. Data from these various sensors will be fused using neural networks to accurately assess damage levels and correlate them with alkali concentrations.
Different ndt-methods-for-polymer-and-composite-materialsMADAN PATNAMSETTY
Â
This document discusses different non-destructive testing (NDT) methods for inspecting polymer and composite materials, including visual inspection, acoustic emission inspection, ultrasonic inspection, and radiographic inspection. It provides details on how each method works and its applications and limitations for inspecting properties of polymers and composites. Comparative studies are presented evaluating the effectiveness of different NDT techniques for detecting defects in glass/epoxy composites and inspecting a composite helicopter rotor blade structure.
NON DESTRUCTIVE TESTING TECHNIQUES ARE USEFUL FOR FINDING DEFECTS LIKE CRACKS,POROSITY,FLAWS,BLOWHOLES IN MATERIALS WITHOUT DESTRUCTING COMPONENT. IT IS ALSO USEFUL FOR TAKING DECISIONS RELATED TO QUALITY OF MATERIAL OR PRODUCT. Non destructive testing includes study and testing of components by various methods such as dye penetration test, eddy current test, magnetic particle test, ndt, radiography test, ultrasonic test.
This document discusses various non-destructive testing (NDT) methods including visual inspection, liquid penetrant testing, magnetic particle testing, ultrasonic testing, eddy current testing, and radiography (X-ray testing). It provides brief descriptions of each method and examples of their applications in evaluating materials and components without causing damage.
This document provides an introduction to non-destructive testing (NDT) methods. It defines NDT as using noninvasive techniques to determine the integrity of a material or structure without causing damage. The six most common NDT methods are described as visual testing, liquid penetrant testing, magnetic particle testing, ultrasonic testing, eddy current testing, and radiographic testing. Examples are given of how each method is used to inspect aircraft components, bridges, pipelines and other structures and materials. NDT plays an important role in quality control and safety across many industries.
Ontario Power Generation developed improvements to surface detection algorithms for their Total Focus Method beam former used in ultrasonic inspection. The previous edge detection strategy used the Canny detector, but required careful tuning and logic. The new bespoke edge detector is better suited to characteristics in high quality TFM images from the Matrix Inspection Technique. It provides more robust results by suppressing noise while identifying isolated discontinuities and rejecting grating lobe artifacts. Modifying the logic also allows isolation of weld pool ripple features to enable superior imaging of the weld volume. Field data shows the enhanced detector and imaging capabilities improve inspection of CANDU reactor pressure boundaries.
Unit-III Non Destructive Testing (NDT)
Subject Name: OML751 Testing of Materials
Topics: Various NDT tests [Visual inspection, Liquid penetrant test, Magnetic particle test, Thermography test, Radiographic test, Eddy current test, Ultrasonic test, Acoustic emission test]
B.E. Mechanical Engineering
Final Year, VII Semester, Open Elective Subject
[As per Anna University R-2017]
This document discusses non-destructive testing (NDT) methods. It begins by defining NDT as techniques used to evaluate materials without causing damage. It then lists common NDT types like visual inspection, liquid penetrant, ultrasonic, and radiographic testing. For each type, it provides a brief overview of the principles and applications. The document focuses on liquid penetrant testing, describing the procedure and noting it is useful for inspecting parts like aircraft wheels and automotive pistons. It also discusses advantages of NDT like avoiding failures and ensuring safety. In conclusion, it states that NDT can save costs for facilities that implement its methods properly.
Magnetic particle testing (MPT) is used to detect surface and near-surface defects in ferromagnetic materials. It works by magnetizing the material, applying iron-based magnetic particles, and looking for patterns in how the particles accumulate at locations where the magnetic field escapes due to defects. Key steps include cleaning, demagnetizing, magnetizing using various methods like permanent magnets or electromagnets, applying dry or wet magnetic particles, illuminating to see indications, interpreting findings, and documenting results. MPT is widely used in industries like manufacturing, aerospace, and infrastructure for quality control and non-destructive testing of parts like castings and welds.
IRJET- In-Situ Monitoring for Fatigue Crack Detection using Control System an...IRJET Journal
Â
This document describes a proposed system for automatic in-situ monitoring of specimens to detect fatigue cracks using image processing and a control system. A camera and Raspberry Pi controller are used to capture images of a specimen under cyclic loading. An image processing algorithm analyzes the images to identify any cracks present based on area and isolate the crack from the background. The algorithm then measures the dimensions of detected cracks. The goal is to alert the user as soon as a crack is found and display the crack dimensions to reduce manual inspection time during fatigue testing. A literature review discusses previous research on fatigue crack detection using techniques like vibration analysis, stroboscopic illumination, and digital image correlation.
NDT Versus Mechanical testing, Overview of the Non Destructive Testing Methods for the detection of manufacturing defects as well as material characterisation. Relative merits and limitations, Various physical characteristics of materials and their applications in NDT., Visual inspection â Unaided and aided
IRJET- Estimation of Propagation Time of Microwave Signal in Different Enviro...IRJET Journal
Â
1. The document analyzes the theoretical estimation of propagation time of microwave signals in different environments.
2. It discusses how the dielectric constant of walls and other materials affects the speed of propagation and time of propagation of microwave signals. Higher dielectric constants result in lower speeds and longer propagation times.
3. MATLAB simulations were used to model signal propagation through walls and analyze the relationships between dielectric constant, reflection coefficient, speed of propagation, and time of propagation. The results show that changes in dielectric constant directly impact these propagation parameters.
A DEEP LEARNING APPROACH FOR DENOISING AIR-COUPLEDULTRASONIC RESPONDS DATAijaia
Â
Ensuring material quality is a central objective in production and manufacturing. Non-contact nondestructive testing methods without the use of coupling media are of particular interest with regard to mechanical or biochemical properties of the material. For this purpose, air-coupled ultrasonic is a useful method for quality control. The challenge is the poor signal-to-noise ratio, which makes it difficult to apply the classical approaches. This makes it impossible to distinguish between defect structures and noise. We are developing a method for denoising air-coupled ultrasonic data by applying deep neural networks by
using a geometry-analytical component that detects defect structures. During the evaluation we show that we are able to obtain the data almost free of noise, so that incorrectly classified noisy pixels are mainly located at the edges of the defect structures, which cannot be clearly delimited. It is shown that the quality of the data is significantly improved for detection processes.
A Review on Detection of Cracks Present in Composite Cantilever Beam by using...ijtsrd
Â
The aim of this paper is to discuss various techniques used by various researchers for vibration based crack detection in cracked composite structures. In aeronautical, mechanical and civil engineering fields various structural systems are likely to damage and deterioration during their working period. So it is very important to find damage and deterioration in structural member by an effective and reliable methodology. Interest in various damage detection methods has considerably increased in last few decades. A local flexibility is introduced in structural member due to the presence of crack that would affect the vibration response of structure. Due to the presence of crack there is reduction in stiffness of structure and increase in damping of the structure. Since there are changes in physical properties there are reductions in natural frequencies and deviation in mode shapes. Therefore by measuring the vibration parameters it is possible to predict crack depth and crack location in structural member. In this paper effect of various parameters like crack depth, crack location on natural frequency of beam is studied.Presence of crack in a beam decreases the natural frequency which is more pronounced when the crack is near the fixed support and the crack depth is more. Mr. Kadam Satish P | Dr. Kachare P.S."A Review on Detection of Cracks Present in Composite Cantilever Beam by using Vibration Analysis Technique" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-1 | Issue-6 , October 2017, URL: http://www.ijtsrd.com/papers/ijtsrd4617.pdf http://www.ijtsrd.com/engineering/mechanical-engineering/4617/a-review-on-detection-of-cracks-present-in-composite-cantilever-beam-by-using-vibration-analysis-technique/mr-kadam-satish-p
Study on Effect of Crack Inclination and Location on Natural Frequency for In...IRJET Journal
Â
This document presents a study on the effect of crack inclination and location on the natural frequency of an inclined edge cracked cantilever beam using finite element analysis. 16 models of a cantilever beam with various crack inclinations were created in ANSYS with the crack located at L/2 and L/4 from the fixed end. Modal analysis was performed to determine the natural frequencies and mode shapes. The results show that the natural frequency decreases with increasing crack inclination and depth due to reduced beam stiffness. Natural frequency is also affected by crack location, with frequencies lower for cracks closer to the fixed end. In conclusion, crack parameters such as inclination, depth and location significantly influence a beam's natural frequency.
Operational Modal Analysis Implementation on a Hybrd Composite PlateHazira Haidzir
Â
This document discusses modal analysis techniques for predicting structural deformation in aerospace structures due to airflow. It compares experimental modal analysis (EMA), which uses artificial excitation, to operational modal analysis (OMA), which extracts modal properties from operational response only. The study implemented OMA on a composite plate using a laser vibrometer for contactless response measurement. OMA results matched an EMA analysis using impact testing, validating the technique. OMA avoids complex artificial excitation and represents actual operating conditions.
This document summarizes research on using magneto-optic imaging for non-destructive testing of metal structures. It describes developing new thin-film sensors with improved sensitivity, integrating the sensors and image recognition algorithms into a portable system, and applying a neural network algorithm called SONON to enhance defect detection in images. Laboratory experiments demonstrated the new sensors could detect smaller defects than previous methods. The overall aim is more accurate, automated inspections using portable, wearable equipment.
This document discusses a novel magneto-optic sensor called the MODE sensor that can be used for non-destructive testing of structural integrity. The MODE sensor uses thin films made of rare earth and transition metal oxides that have high magneto-optic properties, allowing it to detect cracks, fissures, and corrosion in structures. A portable system has been designed using this sensor to allow real-time inspection of bridges, fuel tanks, and other metal structures. The system includes image processing and pattern recognition capabilities to help identify defects.
The document provides an introduction to nondestructive testing (NDT). It defines NDT as inspecting or testing materials without destroying them to find defects. NDT is used across many industries to inspect equipment and ensure safety. Common NDT methods described include visual testing, liquid penetrant testing, magnetic particle testing, ultrasonic testing, electromagnetic testing, radiographic testing, and acoustic emission testing. NDT can be used at all stages of production and equipment lifecycles to detect flaws and ensure quality and integrity.
This document discusses non-destructive testing methods for evaluating materials. It describes several common non-destructive testing techniques such as liquid penetrant inspection, magnetic particle testing, ultrasonic testing, x-ray testing, and visual inspection. These techniques are used to inspect materials for defects without damaging the material. The document also discusses the importance of non-destructive testing for safety, reliability, and cost savings for manufacturers.
Introduction to the non destructive testing explains the methods for evaluating and verifying many types of Materials as plastics, structures, metals, chemicals, leakage, physical properties. It's very used in the concrete engineering world and in the scientific world.
This document discusses using fiber optic sensors with polydimethylsiloxane coatings for structural health monitoring of concrete structures. It aims to develop an affordable monitoring strategy for alkali-aggregate reaction and corrosion detection. The strategy involves a heterogeneous multi-sensor data fusion system using acoustic, electro-mechanical, optical and embedded sensors. Data from these various sensors will be fused using neural networks to accurately assess damage levels and correlate them with alkali concentrations.
Different ndt-methods-for-polymer-and-composite-materialsMADAN PATNAMSETTY
Â
This document discusses different non-destructive testing (NDT) methods for inspecting polymer and composite materials, including visual inspection, acoustic emission inspection, ultrasonic inspection, and radiographic inspection. It provides details on how each method works and its applications and limitations for inspecting properties of polymers and composites. Comparative studies are presented evaluating the effectiveness of different NDT techniques for detecting defects in glass/epoxy composites and inspecting a composite helicopter rotor blade structure.
NON DESTRUCTIVE TESTING TECHNIQUES ARE USEFUL FOR FINDING DEFECTS LIKE CRACKS,POROSITY,FLAWS,BLOWHOLES IN MATERIALS WITHOUT DESTRUCTING COMPONENT. IT IS ALSO USEFUL FOR TAKING DECISIONS RELATED TO QUALITY OF MATERIAL OR PRODUCT. Non destructive testing includes study and testing of components by various methods such as dye penetration test, eddy current test, magnetic particle test, ndt, radiography test, ultrasonic test.
This document discusses various non-destructive testing (NDT) methods including visual inspection, liquid penetrant testing, magnetic particle testing, ultrasonic testing, eddy current testing, and radiography (X-ray testing). It provides brief descriptions of each method and examples of their applications in evaluating materials and components without causing damage.
This document provides an introduction to non-destructive testing (NDT) methods. It defines NDT as using noninvasive techniques to determine the integrity of a material or structure without causing damage. The six most common NDT methods are described as visual testing, liquid penetrant testing, magnetic particle testing, ultrasonic testing, eddy current testing, and radiographic testing. Examples are given of how each method is used to inspect aircraft components, bridges, pipelines and other structures and materials. NDT plays an important role in quality control and safety across many industries.
Ontario Power Generation developed improvements to surface detection algorithms for their Total Focus Method beam former used in ultrasonic inspection. The previous edge detection strategy used the Canny detector, but required careful tuning and logic. The new bespoke edge detector is better suited to characteristics in high quality TFM images from the Matrix Inspection Technique. It provides more robust results by suppressing noise while identifying isolated discontinuities and rejecting grating lobe artifacts. Modifying the logic also allows isolation of weld pool ripple features to enable superior imaging of the weld volume. Field data shows the enhanced detector and imaging capabilities improve inspection of CANDU reactor pressure boundaries.
Unit-III Non Destructive Testing (NDT)
Subject Name: OML751 Testing of Materials
Topics: Various NDT tests [Visual inspection, Liquid penetrant test, Magnetic particle test, Thermography test, Radiographic test, Eddy current test, Ultrasonic test, Acoustic emission test]
B.E. Mechanical Engineering
Final Year, VII Semester, Open Elective Subject
[As per Anna University R-2017]
This document discusses non-destructive testing (NDT) methods. It begins by defining NDT as techniques used to evaluate materials without causing damage. It then lists common NDT types like visual inspection, liquid penetrant, ultrasonic, and radiographic testing. For each type, it provides a brief overview of the principles and applications. The document focuses on liquid penetrant testing, describing the procedure and noting it is useful for inspecting parts like aircraft wheels and automotive pistons. It also discusses advantages of NDT like avoiding failures and ensuring safety. In conclusion, it states that NDT can save costs for facilities that implement its methods properly.
Magnetic particle testing (MPT) is used to detect surface and near-surface defects in ferromagnetic materials. It works by magnetizing the material, applying iron-based magnetic particles, and looking for patterns in how the particles accumulate at locations where the magnetic field escapes due to defects. Key steps include cleaning, demagnetizing, magnetizing using various methods like permanent magnets or electromagnets, applying dry or wet magnetic particles, illuminating to see indications, interpreting findings, and documenting results. MPT is widely used in industries like manufacturing, aerospace, and infrastructure for quality control and non-destructive testing of parts like castings and welds.
IRJET- In-Situ Monitoring for Fatigue Crack Detection using Control System an...IRJET Journal
Â
This document describes a proposed system for automatic in-situ monitoring of specimens to detect fatigue cracks using image processing and a control system. A camera and Raspberry Pi controller are used to capture images of a specimen under cyclic loading. An image processing algorithm analyzes the images to identify any cracks present based on area and isolate the crack from the background. The algorithm then measures the dimensions of detected cracks. The goal is to alert the user as soon as a crack is found and display the crack dimensions to reduce manual inspection time during fatigue testing. A literature review discusses previous research on fatigue crack detection using techniques like vibration analysis, stroboscopic illumination, and digital image correlation.
NDT Versus Mechanical testing, Overview of the Non Destructive Testing Methods for the detection of manufacturing defects as well as material characterisation. Relative merits and limitations, Various physical characteristics of materials and their applications in NDT., Visual inspection â Unaided and aided
IRJET- Estimation of Propagation Time of Microwave Signal in Different Enviro...IRJET Journal
Â
1. The document analyzes the theoretical estimation of propagation time of microwave signals in different environments.
2. It discusses how the dielectric constant of walls and other materials affects the speed of propagation and time of propagation of microwave signals. Higher dielectric constants result in lower speeds and longer propagation times.
3. MATLAB simulations were used to model signal propagation through walls and analyze the relationships between dielectric constant, reflection coefficient, speed of propagation, and time of propagation. The results show that changes in dielectric constant directly impact these propagation parameters.
A DEEP LEARNING APPROACH FOR DENOISING AIR-COUPLEDULTRASONIC RESPONDS DATAijaia
Â
Ensuring material quality is a central objective in production and manufacturing. Non-contact nondestructive testing methods without the use of coupling media are of particular interest with regard to mechanical or biochemical properties of the material. For this purpose, air-coupled ultrasonic is a useful method for quality control. The challenge is the poor signal-to-noise ratio, which makes it difficult to apply the classical approaches. This makes it impossible to distinguish between defect structures and noise. We are developing a method for denoising air-coupled ultrasonic data by applying deep neural networks by
using a geometry-analytical component that detects defect structures. During the evaluation we show that we are able to obtain the data almost free of noise, so that incorrectly classified noisy pixels are mainly located at the edges of the defect structures, which cannot be clearly delimited. It is shown that the quality of the data is significantly improved for detection processes.
A Review on Detection of Cracks Present in Composite Cantilever Beam by using...ijtsrd
Â
The aim of this paper is to discuss various techniques used by various researchers for vibration based crack detection in cracked composite structures. In aeronautical, mechanical and civil engineering fields various structural systems are likely to damage and deterioration during their working period. So it is very important to find damage and deterioration in structural member by an effective and reliable methodology. Interest in various damage detection methods has considerably increased in last few decades. A local flexibility is introduced in structural member due to the presence of crack that would affect the vibration response of structure. Due to the presence of crack there is reduction in stiffness of structure and increase in damping of the structure. Since there are changes in physical properties there are reductions in natural frequencies and deviation in mode shapes. Therefore by measuring the vibration parameters it is possible to predict crack depth and crack location in structural member. In this paper effect of various parameters like crack depth, crack location on natural frequency of beam is studied.Presence of crack in a beam decreases the natural frequency which is more pronounced when the crack is near the fixed support and the crack depth is more. Mr. Kadam Satish P | Dr. Kachare P.S."A Review on Detection of Cracks Present in Composite Cantilever Beam by using Vibration Analysis Technique" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-1 | Issue-6 , October 2017, URL: http://www.ijtsrd.com/papers/ijtsrd4617.pdf http://www.ijtsrd.com/engineering/mechanical-engineering/4617/a-review-on-detection-of-cracks-present-in-composite-cantilever-beam-by-using-vibration-analysis-technique/mr-kadam-satish-p
Study on Effect of Crack Inclination and Location on Natural Frequency for In...IRJET Journal
Â
This document presents a study on the effect of crack inclination and location on the natural frequency of an inclined edge cracked cantilever beam using finite element analysis. 16 models of a cantilever beam with various crack inclinations were created in ANSYS with the crack located at L/2 and L/4 from the fixed end. Modal analysis was performed to determine the natural frequencies and mode shapes. The results show that the natural frequency decreases with increasing crack inclination and depth due to reduced beam stiffness. Natural frequency is also affected by crack location, with frequencies lower for cracks closer to the fixed end. In conclusion, crack parameters such as inclination, depth and location significantly influence a beam's natural frequency.
IRJET- A Fault Diagnosis in Aluminium Honeycomb Structure using Vibration Tec...IRJET Journal
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This document summarizes a study on detecting damage in aluminum honeycomb structures using vibration analysis and finite element modeling. Artificial damage was introduced during manufacturing. Natural frequencies were measured experimentally using an FFT analyzer and compared to ANSYS simulations. Frequency changes between the damaged and undamaged structures were used to locate and quantify damage by plotting contour lines from normalized frequency data. The goal was to identify damage location and severity to improve safety for applications like aircraft and ships.
System identification is an emerging area in engineering fields. To assess the present health of important structures is necessary to know the status of the health of structure and subsequently to improve the health of the structure. In this work, using the finite element software, a simple structural member like beam is modeled. A simply supported beam is taken and crack is initiated at the bottom of the beam along itâs width by reducing the cross section in different location. Free vibration analysis is performed using FEM software SAP2000. There is a difference between the frequencies of cracked and un-cracked beam. From this analysis it can be predicted that there is damage in the beam, but location of the damage cannot be detected. For this, mode shape to be found out. This concept can be used to know in the real life structure whether there is any damage or not using the non-destructive techniques.
Detection of crack location and depth in a cantilever beam by vibration measu...eSAT Journals
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Abstract The presence of a crack is hazardous problem in the performance of many structures and it affects many of the vibration parameters like Natural frequency and mode shapes. Current research has focused on using different modal parameters like natural frequency, mode shape and damping to detect crack in beams. This work concentrates on the parameters like Deflection of a beam, Bending moment and behaviour of stresses. In this work, simulation is carried out by using analysis software ANSYS to find the change in natural frequencies as well as mode shapes for the cracked and uncracked beam. It is then verified by the results obtained from ANN controller and Genetic Algorithm. ANN is used to determine location of crack and its depth along with directions of propagation and Natural frequencies and corresponding mode shapes difference as initial input to calculate the variation and the vibration parameters. The output from ANN controller is corresponding depth and crack location. outputs from numerical analysis are compared with output from Experimentation and they have good resemblance to the results predicted by the ANN controller. Genetic algorithm is an evolutionary type of algorithm which generates the optimized solution to the problems. It is an iterative process to reach to the final solution. By using this, same results are found and related with the results of ANN. And finally the results are compared to find the most appropriate approach amongst the two methods. Keywordsâ ANN, Crack, Depth, GA
Signal-Based Damage Detection Methods â Algorithms and ApplicationsIJERD Editor
Â
This document provides an overview of signal-based damage detection methods for civil structures. It discusses three main categories of these methods: time-domain methods, frequency-domain methods, and time-frequency methods. Various feature extraction algorithms are described for each category, including auto-regressive models, auto-regressive moving average models, and wavelet transforms. Successful applications of these methods to detect damage in bridges, buildings, and mechanical systems are also reviewed. Signal-based methods are effective for structures with nonlinear behavior and noisy sensor measurements.
Damage Detection in Beams Using Frequency Response Function Curvatures Near R...Subhajit Mondal
Â
Structural damage detection from measured vibration responses has gain
popularity among the research community for a long time. Damage is identified in
structures as reduction of stiffness and is determined from its sensitivity towards the
changes in modal properties such as frequency, mode shape or damping values with
respect to the corresponding undamaged state. Damage can also be detected directly
from observed changes in frequency response function (FRF) or its derivatives and
has become popular in recent time. A damage detection algorithm based on FRF
curvature is presented here which can identify both the existence of damage as well
as the location of damage very easily. The novelty of the present method is that the
curvatures of FRF at frequencies other than natural frequencies are used for
detecting damage. This paper tries to identify the most effective zone of frequency
ranges to determine the FRF curvature for identifying damages. A numerical
example has been presented involving a beam in simply supported boundary
condition to prove the concept. The effect of random noise on the damage detection
using the present algorithm has been verified.
IRJET- Cantilever Beam Crack Detection using FEA and FFT AnalyserIRJET Journal
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This document presents a method to detect cracks in cantilever beams using finite element analysis and natural frequency measurements. A cracked beam is modeled as two segments connected by a spring. Natural frequencies are obtained through FEA for uncracked and cracked beams. Equations relate the stiffness of the spring and crack location to changes in natural frequency. Plots of stiffness versus crack location from three modes intersect at the actual location. The method accurately predicts crack size and position to within 4% error. A case study applies the method to a cantilever beam, generating mode shapes through FEA and using equations to determine crack parameters from frequency data.
IRJET-Develpoment and Analysis of Frequency Response Setup for Pole Shoe Ferr...IRJET Journal
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This document discusses the development and analysis of a frequency response setup for non-destructively testing pole shoe components made of carbon steel. The setup uses vibration analysis to detect internal defects in pole shoes. Vibrations are induced using a DC motor and spring assembly, and responses are measured using a vibrometer to obtain frequency, displacement, and acceleration readings. The results are aimed to help identify defective pole shoes early to prevent wasted time and materials from being used in motors. Non-destructive vibration-based testing provides an economical and reliable alternative to other NDT methods for these components.
Free Vibrational Analysis of Cracked and Un-cracked Cantilever BeamIRJET Journal
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1. The document analyzes the free vibrational behavior of cracked and un-cracked cantilever beams through numerical analysis using ANSYS software, analytical solutions using Euler beam theory, and experimental modal analysis.
2. Natural frequencies of the beams are obtained for the first three vibration modes. Ten cracked beam models with varying cross-sections, crack locations, and crack depths are analyzed.
3. Curve fitting and fuzzy logic techniques are introduced to identify crack parameters like location and depth based on the natural frequencies. Results from finite element analysis, numerical analysis, fuzzy logic and experiments are compared.
Damage Identification of Bridge Model by using Natural FrequencyIRJET Journal
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This document summarizes research on using natural frequency to identify damage in a bridge model. The study used SAP 2000 software to analyze the natural frequencies of a Warren truss bridge model for both undamaged and damaged cases. Six mode shapes were considered for the bridge model with three different damage cases that reduced the diameter of structural members. The results showed natural frequencies decreased as member diameters decreased, indicating natural frequency can detect structural damage represented by reduced member sizes. The goal was to develop an effective method to identify structural deterioration by monitoring changes in natural frequency.
This document is a term paper presentation on vibration-based damage detection techniques. It was presented by Umar Shahab Karimi under the supervision of Prof. Khalid Moin of the Department of Civil Engineering at Jamia Millia Islamia University. The paper discusses how vibration testing can be used as a non-destructive technique to detect damage in structures by analyzing changes in modal parameters like natural frequencies and mode shapes. It reviews several past studies on using changes in vibration characteristics to identify damage locations and severity levels. The objective is to understand vibration-based damage detection and applications/limitations. Several methods are characterized and factors affecting successful implementation are discussed.
This document discusses a patent for structural health monitoring systems and methods. Specifically, the patent proposes improved vibration-based methods for damage diagnosis and modeling. It introduces a new concept of designing structures to increase damage detection sensitivity. For damage modeling, the outlined method can find eigenvalues and eigenfunctions for any damaged structure shape, faster than finite element methods by avoiding remeshing. It also provides higher sensitivity damage diagnosis without requiring a baseline structure response.
Structural health monitoring 2011-wei fan-83-111Hajar Ch
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The document is a review article that summarizes vibration-based damage identification methods for beam and plate structures. It classifies methods into four categories: natural frequency-based methods, mode shape-based methods, curvature mode shape-based methods, and methods using multiple modal parameters. Natural frequency methods use changes in frequencies to detect damage but may not uniquely identify damage location. Mode shape methods analyze changes in mode shapes but typically only provide damage localization. Curvature methods are generally effective for localization. The article then compares implementations of five damage detection algorithms for beams to evaluate effectiveness of signal processing methods.
IRJET- Harmonic Analysis of Cantilever Beam with and without CracksIRJET Journal
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The document discusses the harmonic analysis of cantilever beams with and without cracks using finite element analysis software SAP2000. Cantilever steel and concrete beam models were developed with varying crack depths and locations. Modal analysis was performed to determine the natural frequencies and mode shapes of the beams. The results show that the presence of cracks, especially those closer to the fixed end, reduce the natural frequencies of beams compared to uncracked beams. Deeper cracks produce a larger decrease in natural frequency. Cracked beams also experience greater displacement under harmonic loads than uncracked beams due to the reduction in stiffness caused by cracks. The study aims to evaluate how crack parameters like depth and location influence vibration characteristics of beams.
Crack Detection of Ferromagnetic Materials through Non Destructive Testing Me...IJMER
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The real components have so many defects in the material, which acts as a crack. In fact,
manufacturing of a component is not ideal. In manufacturing several kinds of defects are generated
like voids and inclusions. Thus, it must be check all the critical components through non-destructive
techniques (NDT) to detect the potential dangerous cracks. In Certain crucial components such as
Airplanes, Space Vehicles, Nuclear Plants, Heavy Machinery, Dams, Concrete etc., online monitoring
of defects is necessary. Concrete is different from other construction materials. Concrete can be made
from combination of different materials. Its final properties depend on its treatment at construction
site. To achieve this, sophisticated technologies are used. Ferromagnetic Composite Iron (FCI) is
used in power generating devices and DC brushless Motors. Laminations can be substituted by
Ferromagnetic Composite Iron (FCI) materials which offer a great manufacturing advantage. Non
Destructive testing (NDT) is a major part of quality control. In Non-Destructive testing (NDT)
different materials are tested for surface, volumetric and internal defects present in it. Non
Destructive testing (NDT) is also an assurance that the proposed product is good and reliable. To
apply these techniques, a certain level of skills is very necessary so that maximum amount of
information is fetched related to the proposed product during testing. This paper deals with the Non
Destructive Testing Methodology Used for crack detection in ferromagnetic materials.
The document discusses techniques for analyzing materials that have fractured. Chemical analysis can identify deviations from specifications, impurities, and corrosion products. Mechanical testing determines if the material's properties met standards and withstood stresses. Nondestructive evaluation techniques like ultrasonics, radiography, and eddy currents detect subsurface flaws without destroying the component. Together, these analyses provide information about what caused the material to fracture.
The document discusses using modal analysis and frequency response functions (FRF) to analyze the state of wall elements. Modal analysis involves exciting wall elements and measuring their response over time. The FRF relates the input excitation signal to the output response signal and can reveal differences between intact and damaged wall elements. The author uses software to perform experimental modal analysis on various wall materials like bricks. Frequency response functions are obtained and displayed for intact and damaged bricks in different directions. The results show differences in the FRFs that could help diagnose the state of wall elements nondestructively.
IRJET- Vibration Analysis of Simply Supported Beam with Varying Crack Dep...IRJET Journal
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This document discusses using finite element analysis in ANSYS to analyze vibration in a simply supported beam with cracks of varying depth and location. It first provides background on using changes in natural frequency and mode shapes to detect damage in structures. It then reviews previous research on modeling cracks and their effects in beams. The document describes developing finite element models of cracked and uncracked beams in ANSYS to calculate natural frequencies and compare to theoretical results. The goal is to present results of using vibration analysis for crack detection.
Testing comprise all the techniques of materials or products under different types of loadings. This way, the reliability of product to end user is assured and the process of material selection is done with a lot of ease.
Testing can be classified in two main categories depending upon destruction of products as
Destructive Testing
Non-Destructive Testing
These comprises all those techniques which are highly regulated on some standard in which specimen is broken/destructed.
Major destructive testing used these days are
Tensile Testing
Impact Testing
Burst Testing
Fatigue Testing
Creep Testing
Non-destructive testing (NDT) is a wide group of analysis techniques used in science and industry to evaluate the properties of a material, component or system without causing damage.
Another terms for NDT is NDE
Highly valuable technique that can save both money and time in product evaluation.
Accident prevention and to reduce costsÂ
To improve product reliabilityÂ
To determine acceptance to a given requirementÂ
To quick information on repair criteria.
Visual Inspection
Acoustic Emission
Eddy Current
Liquid Penetrant
X-Ray/ Radiography
Magnetic method
Visual and optical inspection (or testing) is still a basic method for many applications. Visual inspection involves using an inspector's eyes to look for defects. The inspector may also use special tools such as magnifying glasses, mirrors, or bore scopes to gain access and more closely inspect the subject area. Visual examiners follow procedures that range from simple to very complex.
Detection and analysis of AE signals can supply valuable information regarding the origin and importance of a discontinuity in a material.
It has many industrial applications
Assessing structural integrity (Welding)
Detecting flaws
Testing for leaks (Pressure Vessel)
Monitoring weld quality
Research tool.
In a standard eddy current testing a circular coil carrying current is which generates eddy current then the presence of any flaws, will cause a change in eddy current and a corresponding change in the phase and amplitude of the measured current.
Applications:
Surface Breaking Cracks
SBC using Sliding Probes
Tube Inspection Conductivity
Heat Treat Verification
In it the defects/cracks are studied using a penetrant/dye. low surface tension fluid penetrates into clean and dry surface-breaking discontinuities. Penetrant may be applied to the test component by dipping, spraying, or brushing. After adequate penetration time has been allowed, the excess penetrant is removed and a developer is applied. The developer helps to draw penetrant out of the flaw so that an invisible indication becomes visible to the inspector. Inspection is performed under ultraviolet or white light
X-rays are just like any other kind of electromagnetic radiation. They can be produced in parcels of energy called photons, just like light.
These are used to produce image
Driving Business Innovation: Latest Generative AI Advancements & Success StorySafe Software
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Are you ready to revolutionize how you handle data? Join us for a webinar where weâll bring you up to speed with the latest advancements in Generative AI technology and discover how leveraging FME with tools from giants like Google Gemini, Amazon, and Microsoft OpenAI can supercharge your workflow efficiency.
During the hour, weâll take you through:
Guest Speaker Segment with Hannah Barrington: Dive into the world of dynamic real estate marketing with Hannah, the Marketing Manager at Workspace Group. Hear firsthand how their team generates engaging descriptions for thousands of office units by integrating diverse data sourcesâfrom PDF floorplans to web pagesâusing FME transformers, like OpenAIVisionConnector and AnthropicVisionConnector. This use case will show you how GenAI can streamline content creation for marketing across the board.
Ollama Use Case: Learn how Scenario Specialist Dmitri Bagh has utilized Ollama within FME to input data, create custom models, and enhance security protocols. This segment will include demos to illustrate the full capabilities of FME in AI-driven processes.
Custom AI Models: Discover how to leverage FME to build personalized AI models using your data. Whether itâs populating a model with local data for added security or integrating public AI tools, find out how FME facilitates a versatile and secure approach to AI.
Weâll wrap up with a live Q&A session where you can engage with our experts on your specific use cases, and learn more about optimizing your data workflows with AI.
This webinar is ideal for professionals seeking to harness the power of AI within their data management systems while ensuring high levels of customization and security. Whether you're a novice or an expert, gain actionable insights and strategies to elevate your data processes. Join us to see how FME and AI can revolutionize how you work with data!
Taking AI to the Next Level in Manufacturing.pdfssuserfac0301
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Read Taking AI to the Next Level in Manufacturing to gain insights on AI adoption in the manufacturing industry, such as:
1. How quickly AI is being implemented in manufacturing.
2. Which barriers stand in the way of AI adoption.
3. How data quality and governance form the backbone of AI.
4. Organizational processes and structures that may inhibit effective AI adoption.
6. Ideas and approaches to help build your organization's AI strategy.
Main news related to the CCS TSI 2023 (2023/1695)Jakub Marek
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An English đŹđ§ translation of a presentation to the speech I gave about the main changes brought by CCS TSI 2023 at the biggest Czech conference on Communications and signalling systems on Railways, which was held in Clarion Hotel Olomouc from 7th to 9th November 2023 (konferenceszt.cz). Attended by around 500 participants and 200 on-line followers.
The original Czech đšđż version of the presentation can be found here: https://www.slideshare.net/slideshow/hlavni-novinky-souvisejici-s-ccs-tsi-2023-2023-1695/269688092 .
The videorecording (in Czech) from the presentation is available here: https://youtu.be/WzjJWm4IyPk?si=SImb06tuXGb30BEH .
âTemporal Event Neural Networks: A More Efficient Alternative to the Transfor...Edge AI and Vision Alliance
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For the full video of this presentation, please visit: https://www.edge-ai-vision.com/2024/06/temporal-event-neural-networks-a-more-efficient-alternative-to-the-transformer-a-presentation-from-brainchip/
Chris Jones, Director of Product Management at BrainChip , presents the âTemporal Event Neural Networks: A More Efficient Alternative to the Transformerâ tutorial at the May 2024 Embedded Vision Summit.
The expansion of AI services necessitates enhanced computational capabilities on edge devices. Temporal Event Neural Networks (TENNs), developed by BrainChip, represent a novel and highly efficient state-space network. TENNs demonstrate exceptional proficiency in handling multi-dimensional streaming data, facilitating advancements in object detection, action recognition, speech enhancement and language model/sequence generation. Through the utilization of polynomial-based continuous convolutions, TENNs streamline models, expedite training processes and significantly diminish memory requirements, achieving notable reductions of up to 50x in parameters and 5,000x in energy consumption compared to prevailing methodologies like transformers.
Integration with BrainChipâs Akida neuromorphic hardware IP further enhances TENNsâ capabilities, enabling the realization of highly capable, portable and passively cooled edge devices. This presentation delves into the technical innovations underlying TENNs, presents real-world benchmarks, and elucidates how this cutting-edge approach is positioned to revolutionize edge AI across diverse applications.
In the realm of cybersecurity, offensive security practices act as a critical shield. By simulating real-world attacks in a controlled environment, these techniques expose vulnerabilities before malicious actors can exploit them. This proactive approach allows manufacturers to identify and fix weaknesses, significantly enhancing system security.
This presentation delves into the development of a system designed to mimic Galileo's Open Service signal using software-defined radio (SDR) technology. We'll begin with a foundational overview of both Global Navigation Satellite Systems (GNSS) and the intricacies of digital signal processing.
The presentation culminates in a live demonstration. We'll showcase the manipulation of Galileo's Open Service pilot signal, simulating an attack on various software and hardware systems. This practical demonstration serves to highlight the potential consequences of unaddressed vulnerabilities, emphasizing the importance of offensive security practices in safeguarding critical infrastructure.
Dandelion Hashtable: beyond billion requests per second on a commodity serverAntonios Katsarakis
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This slide deck presents DLHT, a concurrent in-memory hashtable. Despite efforts to optimize hashtables, that go as far as sacrificing core functionality, state-of-the-art designs still incur multiple memory accesses per request and block request processing in three cases. First, most hashtables block while waiting for data to be retrieved from memory. Second, open-addressing designs, which represent the current state-of-the-art, either cannot free index slots on deletes or must block all requests to do so. Third, index resizes block every request until all objects are copied to the new index. Defying folklore wisdom, DLHT forgoes open-addressing and adopts a fully-featured and memory-aware closed-addressing design based on bounded cache-line-chaining. This design offers lock-free index operations and deletes that free slots instantly, (2) completes most requests with a single memory access, (3) utilizes software prefetching to hide memory latencies, and (4) employs a novel non-blocking and parallel resizing. In a commodity server and a memory-resident workload, DLHT surpasses 1.6B requests per second and provides 3.5x (12x) the throughput of the state-of-the-art closed-addressing (open-addressing) resizable hashtable on Gets (Deletes).
HCL Notes und Domino Lizenzkostenreduzierung in der Welt von DLAUpanagenda
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Webinar Recording: https://www.panagenda.com/webinars/hcl-notes-und-domino-lizenzkostenreduzierung-in-der-welt-von-dlau/
DLAU und die Lizenzen nach dem CCB- und CCX-Modell sind fĂŒr viele in der HCL-Community seit letztem Jahr ein heiĂes Thema. Als Notes- oder Domino-Kunde haben Sie vielleicht mit unerwartet hohen Benutzerzahlen und LizenzgebĂŒhren zu kĂ€mpfen. Sie fragen sich vielleicht, wie diese neue Art der Lizenzierung funktioniert und welchen Nutzen sie Ihnen bringt. Vor allem wollen Sie sicherlich Ihr Budget einhalten und Kosten sparen, wo immer möglich. Das verstehen wir und wir möchten Ihnen dabei helfen!
Wir erklĂ€ren Ihnen, wie Sie hĂ€ufige Konfigurationsprobleme lösen können, die dazu fĂŒhren können, dass mehr Benutzer gezĂ€hlt werden als nötig, und wie Sie ĂŒberflĂŒssige oder ungenutzte Konten identifizieren und entfernen können, um Geld zu sparen. Es gibt auch einige AnsĂ€tze, die zu unnötigen Ausgaben fĂŒhren können, z. B. wenn ein Personendokument anstelle eines Mail-Ins fĂŒr geteilte Mailboxen verwendet wird. Wir zeigen Ihnen solche FĂ€lle und deren Lösungen. Und natĂŒrlich erklĂ€ren wir Ihnen das neue Lizenzmodell.
Nehmen Sie an diesem Webinar teil, bei dem HCL-Ambassador Marc Thomas und Gastredner Franz Walder Ihnen diese neue Welt nĂ€herbringen. Es vermittelt Ihnen die Tools und das Know-how, um den Ăberblick zu bewahren. Sie werden in der Lage sein, Ihre Kosten durch eine optimierte Domino-Konfiguration zu reduzieren und auch in Zukunft gering zu halten.
Diese Themen werden behandelt
- Reduzierung der Lizenzkosten durch Auffinden und Beheben von Fehlkonfigurationen und ĂŒberflĂŒssigen Konten
- Wie funktionieren CCB- und CCX-Lizenzen wirklich?
- Verstehen des DLAU-Tools und wie man es am besten nutzt
- Tipps fĂŒr hĂ€ufige Problembereiche, wie z. B. Team-PostfĂ€cher, Funktions-/Testbenutzer usw.
- Praxisbeispiele und Best Practices zum sofortigen Umsetzen
How information systems are built or acquired puts information, which is what they should be about, in a secondary place. Our language adapted accordingly, and we no longer talk about information systems but applications. Applications evolved in a way to break data into diverse fragments, tightly coupled with applications and expensive to integrate. The result is technical debt, which is re-paid by taking even bigger "loans", resulting in an ever-increasing technical debt. Software engineering and procurement practices work in sync with market forces to maintain this trend. This talk demonstrates how natural this situation is. The question is: can something be done to reverse the trend?
Programming Foundation Models with DSPy - Meetup SlidesZilliz
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Prompting language models is hard, while programming language models is easy. In this talk, I will discuss the state-of-the-art framework DSPy for programming foundation models with its powerful optimizers and runtime constraint system.
Conversational agents, or chatbots, are increasingly used to access all sorts of services using natural language. While open-domain chatbots - like ChatGPT - can converse on any topic, task-oriented chatbots - the focus of this paper - are designed for specific tasks, like booking a flight, obtaining customer support, or setting an appointment. Like any other software, task-oriented chatbots need to be properly tested, usually by defining and executing test scenarios (i.e., sequences of user-chatbot interactions). However, there is currently a lack of methods to quantify the completeness and strength of such test scenarios, which can lead to low-quality tests, and hence to buggy chatbots.
To fill this gap, we propose adapting mutation testing (MuT) for task-oriented chatbots. To this end, we introduce a set of mutation operators that emulate faults in chatbot designs, an architecture that enables MuT on chatbots built using heterogeneous technologies, and a practical realisation as an Eclipse plugin. Moreover, we evaluate the applicability, effectiveness and efficiency of our approach on open-source chatbots, with promising results.
Introduction of Cybersecurity with OSS at Code Europe 2024Hiroshi SHIBATA
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I develop the Ruby programming language, RubyGems, and Bundler, which are package managers for Ruby. Today, I will introduce how to enhance the security of your application using open-source software (OSS) examples from Ruby and RubyGems.
The first topic is CVE (Common Vulnerabilities and Exposures). I have published CVEs many times. But what exactly is a CVE? I'll provide a basic understanding of CVEs and explain how to detect and handle vulnerabilities in OSS.
Next, let's discuss package managers. Package managers play a critical role in the OSS ecosystem. I'll explain how to manage library dependencies in your application.
I'll share insights into how the Ruby and RubyGems core team works to keep our ecosystem safe. By the end of this talk, you'll have a better understanding of how to safeguard your code.
HCL Notes and Domino License Cost Reduction in the World of DLAUpanagenda
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Webinar Recording: https://www.panagenda.com/webinars/hcl-notes-and-domino-license-cost-reduction-in-the-world-of-dlau/
The introduction of DLAU and the CCB & CCX licensing model caused quite a stir in the HCL community. As a Notes and Domino customer, you may have faced challenges with unexpected user counts and license costs. You probably have questions on how this new licensing approach works and how to benefit from it. Most importantly, you likely have budget constraints and want to save money where possible. Donât worry, we can help with all of this!
Weâll show you how to fix common misconfigurations that cause higher-than-expected user counts, and how to identify accounts which you can deactivate to save money. There are also frequent patterns that can cause unnecessary cost, like using a person document instead of a mail-in for shared mailboxes. Weâll provide examples and solutions for those as well. And naturally weâll explain the new licensing model.
Join HCL Ambassador Marc Thomas in this webinar with a special guest appearance from Franz Walder. It will give you the tools and know-how to stay on top of what is going on with Domino licensing. You will be able lower your cost through an optimized configuration and keep it low going forward.
These topics will be covered
- Reducing license cost by finding and fixing misconfigurations and superfluous accounts
- How do CCB and CCX licenses really work?
- Understanding the DLAU tool and how to best utilize it
- Tips for common problem areas, like team mailboxes, functional/test users, etc
- Practical examples and best practices to implement right away
Fueling AI with Great Data with Airbyte WebinarZilliz
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This talk will focus on how to collect data from a variety of sources, leveraging this data for RAG and other GenAI use cases, and finally charting your course to productionalization.
Monitoring and Managing Anomaly Detection on OpenShift.pdfTosin Akinosho
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Monitoring and Managing Anomaly Detection on OpenShift
Overview
Dive into the world of anomaly detection on edge devices with our comprehensive hands-on tutorial. This SlideShare presentation will guide you through the entire process, from data collection and model training to edge deployment and real-time monitoring. Perfect for those looking to implement robust anomaly detection systems on resource-constrained IoT/edge devices.
Key Topics Covered
1. Introduction to Anomaly Detection
- Understand the fundamentals of anomaly detection and its importance in identifying unusual behavior or failures in systems.
2. Understanding Edge (IoT)
- Learn about edge computing and IoT, and how they enable real-time data processing and decision-making at the source.
3. What is ArgoCD?
- Discover ArgoCD, a declarative, GitOps continuous delivery tool for Kubernetes, and its role in deploying applications on edge devices.
4. Deployment Using ArgoCD for Edge Devices
- Step-by-step guide on deploying anomaly detection models on edge devices using ArgoCD.
5. Introduction to Apache Kafka and S3
- Explore Apache Kafka for real-time data streaming and Amazon S3 for scalable storage solutions.
6. Viewing Kafka Messages in the Data Lake
- Learn how to view and analyze Kafka messages stored in a data lake for better insights.
7. What is Prometheus?
- Get to know Prometheus, an open-source monitoring and alerting toolkit, and its application in monitoring edge devices.
8. Monitoring Application Metrics with Prometheus
- Detailed instructions on setting up Prometheus to monitor the performance and health of your anomaly detection system.
9. What is Camel K?
- Introduction to Camel K, a lightweight integration framework built on Apache Camel, designed for Kubernetes.
10. Configuring Camel K Integrations for Data Pipelines
- Learn how to configure Camel K for seamless data pipeline integrations in your anomaly detection workflow.
11. What is a Jupyter Notebook?
- Overview of Jupyter Notebooks, an open-source web application for creating and sharing documents with live code, equations, visualizations, and narrative text.
12. Jupyter Notebooks with Code Examples
- Hands-on examples and code snippets in Jupyter Notebooks to help you implement and test anomaly detection models.
Monitoring and Managing Anomaly Detection on OpenShift.pdf
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1. International Journal of Computational Engineering Research||Vol, 04||Issue, 4||
||Issn 2250-3005 || || April || 2014 || Page 39
Experimental investigation of crack in aluminum cantilever beam
using vibration monitoring technique
1,
Akhilesh Kumar, & 2,
J. N. Mahto
1,
(Department of Mechanical Engineering, B.I.T. Sindri)
2,
(Assistant Professor, Department of Mechanical Engineering, B.I.T. Sindri)
V. B. U. Hazaribag
I. INTRODUCTION
The interest in the ability to monitor a structure and detect damage at the earliest possible stage is
pervasive throughout the civil, mechanical and aerospace engineering communities. Current damage-detection
methods are either visual or localized experimental methods such as acoustic or ultrasonic methods, magnet
field methods, radiographs, eddy-current methods or thermal field methods. All of these experimental
techniques require that the vicinity of the damage is known a priori and that the portion of the structure being
inspected is readily accessible. Subjected to these limitations, these experimental methods can detect damage on
or near the surface of the structure. The need for additional global damage detection methods that can be applied
to complex structures has led to the development of methods that examine changes in the vibration
characteristics of the structure. Damage or fault detection, as determined by changes in the dynamic properties
or response of structures, is a subject that has received considerable attention in the literature. The basic idea is
that modal parameters (notably frequencies and mode shapes) are functions of the physical properties of the
structure. Therefore, changes in the physical properties will cause changes in the modal properties. Ideally, a
robust damage detection scheme will be able to identify that damage has occurred at a very early stage, locate
the damage within the sensor resolution being used, provide some estimate of the severity of the damage, and
predict the remaining useful life of the structure. The method should also be well-suited to automation. To the
greatest extent possible, the method should not rely on the engineering judgment of the user or an analytical
model of the structure. A less ambitious, but more attainable, goal would be to develop a method that has the
features listed above, but that uses an initial measurement of an undamaged structure as the baseline for future
comparisons of measured response. Also, the methods should be able to take into account operational
constraints. For example, a common assumption with most damage- identification methods reported in the
technical literature to date is that the mass of the structure does not change appreciably as a result of the damage.
However, there are certain types of structures such as offshore oil platforms where this assumption is not valid.
Another important feature of damage-identification methods, and specifically those methods which use prior
models, is their ability to discriminate between the model/data discrepancies caused by modeling errors and the
discrepancies that are a result of structural damage. The effects of damage on a structure can be classified as
ABTRACT:
It has been observed that the dynamic behaviour of a structure changes due to the presence of a crack.
Analysis of such phenomena is useful for fault diagnosis and the detection of cracks in structures. An
experimental setup is designed in which an aluminium cantilever beam with cracks is excited by a power
exciter and accelerometer attached to the beam provides the response. The cracks are assumed to be
open to avoid non-linearity. The effects of crack and positions on the fundamental frequencies of slender
cantilever beams with edge cracks are investigated experimentally. The experiments are conducted
using specimens having edge cracks of different depths at different positions to validate the numerical
results obtained. The experimental results of frequencies can be obtained from digital storage
oscilloscope (DSO).
The first three natural frequencies were considered as basic criterion for crack detection. To
locate the crack, 3D graphs of the normalized frequency in terms of the crack depth and location are
plotted. The intersection of these three contours gives crack location and crack depth. Out of several
case studies conducted the results of one of the case study is presented to demonstrate the applicability
and efficiency of the method suggested.
Index term: - Cantilever Beam, Oscilloscope, Power Oscillator, Vibration Exciter, Accelerometer etc.
2. Experimental investigation of crack in aluminum cantilever beam using vibrationâŠ
||Issn 2250-3005 || || April || 2014 || Page 40
linear or nonlinear. A linear damage situation is defined as the case when the initially linear-elastic structure
remains linear-elastic after damage. The changes in modal properties are a result of changes in the geometry
and/or the material properties of the structure, but the structural response can still be modeled using a linear
equation of motion. Nonlinear damage is defined as the case when the initially linear-elastic structure behaves in
a nonlinear manner after the damage has been introduced. One example of nonlinear damage is the formation of
a fatigue crack that subsequently opens and closes under the normal operating vibration environment. Other
examples include loose connections that rattle and nonlinear material behavior. A robust damage-detection
method will be applicable to both of these general types of damage. The majority of the papers summarized in
this review address only the problem of linear damage detection.
1.1 PRESENT AIM OF WORK
For conducting the experiment, first of all we will be preparing the machine setup. This machine is
already available in the market, but our aim is to prepare this machine using some conventional machining
methods, so that we can have a machine at a cheap rate. The machine will be measuring the vibration response
of the aluminum solid beam. Vibration response will be taken through beam with the help of oscilloscope.
II. LITERATURE REVIEW
2.1 PRESENT WORK
For the literature review primarily various journals selected. The brief reviews of these papers are as
follow.
Scott W. et. al.[1]
Studied this report contained a review of the technical literature concerning the
detection, location, and characterization of structural damage via techniques that examine changes in measured
structural vibration response. The report was first categorizes the methods according to required measured data
and analysis technique. The analysis categorized includes changes in modal frequencies, changes in measured
mode shapes and changes in measured flexibility coefficients. Methods that use property (stiffness, mass,
damping) matrix updating, detection of nonlinear response, and damage detection via neural networks are also
summarized.
Prasad Ramchandra Baviskar et. al.[2]
This paper addressed the method of multiple cracks detection
in moving parts or beams by monitoring the natural frequency and prediction of crack location and depth using
Artificial Neural Networks (ANN). Determination of crack properties like depth and location is vital in the fault
diagnosis of rotating machine equipments. For the theoretical analysis, Finite Element Method (FEM) is used
wherein the natural frequency of beam is calculated whereas the experimentation is performed using Fast
Fourier Transform (FFT) analyzer. In experimentation, simply supported beam with single crack and cantilever
beam with two cracks are considered. The experimental results are validated with the results of FEM
(ANSYSTM) software. This formulation can be extended for various boundary conditions as well as varying
cross sectional areas. The database obtained by FEM is used for prediction of crack location and depth using
Artificial Neural Network (ANN). To investigate the validity of the proposed method, some predictions by ANN
are compared with the results given by FEM. It is found that the method is capable of predicting the crack
location and depth for single as well as two cracks. This work may be useful for improving online conditioning
and monitoring of machine components and integrity assessment of the structures.
Lee et. al.[3]
presented a method to detect a crack in a beam. The crack was not modeled as a mass less
rotational spring, and the forward problem was solved for the natural frequencies using the boundary element
method. The inverse problem was solved iteratively for the crack location and the crack size by the Newton-
Raphson method. The present crack identification procedure was applied to the simulation cases which use the
experimentally measured natural frequencies as inputs, and the detected crack parameters are in good
agreements with the actual ones. The present method enables one to detect a crack in a beam without the help of
the mass less rotational spring model.
Rizos et. al.[4]
Modeled the crack as a mass less rotational spring, whose stiffness was calculated using
fractures mechanics. He also conducted experiments to detect crack depth and location from changes in the
mode shapes of cantilever beams. A major disadvantage of using mode shape based technique is that obtaining
accurate mode shapes involves arduous and meticulous measurement of displacement or acceleration over a
large number of points on the structure before and after damage. The accuracy in measurement of mode shapes
is highly dependent on the number and distribution of sensors employed.
Owolabi et. al.[5]
used natural frequency as the basic criterion for crack detection in simply supported
and fixed-fixed beams. The method suggested has been extended to cantilever beams to check the capability and
efficiency. There is need to see if this approach can be used for fixed-free beams.
Kisa et. al.[6]
The vibration characteristics of a cracked Timoshenko beam are analyzed. The study
integrates the FEM and component mode synthesis. The beam divided into two components related by a
flexibility matrix which incorporates the interaction forces. The forces were derived from fracture mechanics
3. Experimental investigation of crack in aluminum cantilever beam using vibrationâŠ
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expressions as the inverse of the compliance matrix is calculated using stress intensity factors and strain energy
release rate expressions.
III. EXPERIMENTAL SETUP
3.1 MODEL DESCRIPTION
Aluminum beams were used for this experimental investigation. The setup consisted of 64 beam
models with the fixed-free ends. Each beam model was of cross-sectional area 16mm X 16 mm with a length of
450 mm from fixed end. It had the following material properties: Youngâs modulus, E=70GPa, density,
Ï=2700Kg/m 3, the Poisson ratio, ”=0.33.
Fig: - 1. Experimental Setup
3.2 METHODOLOGY
The fixedâfree beam model was clamped at one end, between two thick rectangular steel plates. The
beam was excited with a vibration exciter. The first three natural frequencies of the un-cracked beam were
measured. Then, cracks were generated to the desired depth using hexa blade. The crack always remained open
during dynamic testing total 64 beam models were tested with cracks at different locations starting from a
location near to fixed end. The crack depth varied from 2mm to 10mm at each crack position. Each model was
excited by vibration exciter. This served as the input to the system. It is to be noted that the model was excited at
a point, which was a few millimeters away from the center of the model. This was done to avoid exciting the
beam at a nodal point. Since the beam would not respond for that mode at that point. The dynamic responses of
the beam model were measured by using accelerometer placed on the model as indicated in Fig. 1. The response
measurements were acquired, one at a time, using the digital storage oscilloscope (DSO).
IV. RESULTS AND DISCUSSION
4.1 RESULTS
The experimental data from the curve-fitted results were tabulated, and plotted (in a three dimensional
plot) in the form of frequency ratio (Ïc/Ï) (ratio of the natural frequency of the cracked beam to that of the un-
cracked beam) versus the crack depth (a) for various crack location (X). Tables 1-3 show the variation of the
frequency ratio as a function of the crack depth and crack location for beams with fixed-free ends.
4.2 CHANGES IN NATURAL FREQUENCY
Fig. 2 to 4 shows the plots of the first three frequency ratios as a function of crack depths for some of
the crack positions. Fig.5 to Fig.7 shows the frequency ratio variation of three modes in terms of crack position
for various crack depths respectively. From Fig.2 it is observed that, for the cases considered, the fundamental
natural frequency was least affected when the crack was located at 360mm from fixed end. The crack was
mostly affected when the crack was located at 40mm from the fixed end. Hence for a cantilever beam, it could
be inferred that the fundamental frequency decreases significantly as the crack location moves towards the fixed
end of the beam. This could be explained by the fact that the decrease in frequencies is greatest for a crack
located where the bending moment is greatest. It appears therefore that the change in frequencies is a function of
crack location. From Fig.3 it is observed that the second natural frequency was mostly affected for a crack
located at the center for all crack depths of a beam due to the fact that at that location the bending moment is
having large value. The second natural frequency was least affected when the crack was located at 360mm from
fixed end. From Fig.4 it is observed that the third natural frequency of beam changed rapidly for a crack located
at 250 mm. The third natural frequency was almost unaffected for a crack located at the center of a cantilever
beam; the reason for this zero influence was that the nodal point for the third mode was located at the center of
beam
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Fig.2. Fundamental natural frequency ratio in terms of crack depth for various crack positions
6. Experimental investigation of crack in aluminum cantilever beam using vibrationâŠ
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Fig.3. Second natural frequency ratio in terms of crack depth for various crack positions
From Fig.6 it is observed that the second natural frequency was mostly affected for a crack depth of 10mm at
the crack location 150mm. The second natural frequency was least affected when the crack depth was 10mm.
From Fig.7 it is observed that the third natural frequency of beam changed rapidly for a crack depth of 10mm.
Third natural frequency was remained unaffected when crack depth was 6mm. Third natural frequency was
remained unchanged at crack locations 55mm, 220mm, and 300mm due to the presence of node point at that
position. Fig.8 to Fig.10 show the three dimensional plots of Normalized Frequency versus Crack Location and
Crack Depth for first, second and third mode respectively for crack location of 250mm and crack depth of 6mm.
To get these three dimensional plots. In Fig.8 to Fig.10, the contour line is not present due to the presence of
node points.
4.3 CRACK IDENTIFICATION TECHNIQUE USING CHANGES IN NATURAL FREQUENCIES
As stated earlier, both the crack location and the crack depth influence the changes in the natural
frequencies of a cracked beam. Consequently, a particular frequency could correspond to different crack
locations and crack depths. This can be observed from the three-dimensional plots of the first three natural
frequencies of cantilever beams as shown in Fig.8 to Fig.10. On this basis, a contour line, which has the same
normalized frequency change resulting from a combination of different crack depths and crack locations (for a
particular mode) could be plotted in a curve with crack location and crack depth as its axes.
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Fig.4. Third natural frequency ratio in terms of crack depth for various crack positions
Fig.5. First Mode Frequency Ratio in Terms of Crack Position for Various Crack Depths
Fig.6. Second Mode Frequency Ratio in Terms of Crack Position for Various Crack Depths
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Fig.7. Third Mode Frequency Ratio in Terms of Crack Position for Various Crack Depths
Fig.8. Three-dimensional plot with contour lines of normalized natural frequency versus crack location and
crack depth for first mode for crack location of 250mm and crack depth of 6mm
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Fig.9. Three-dimensional plot with contour lines of normalized natural frequency versus crack location and
crack depth for second mode for crack location of 250mm and crack depth of 6mm
For a beam with a single crack with unknown parameters, the following steps are required to predict
the crack location, and depth, namely, (1) measurements of the first three natural frequencies; (2) normalization
of the measured frequencies; (3) plotting of contour lines from different modes on the same axes; and (4)
location of the point(s) of intersection of the different contour lines. The point(s) of intersection, common to all
the three modes, indicate(s) the crack location, and crack depth. This intersection will be unique due to the fact
that any normalized crack frequency can be represented by a governing equation that is dependent on crack
depth (a), crack location (X). Therefore a minimum of three curves is required to identify the two unknown
parameters of crack location and crack depth.
Fig.10. Three-dimensional plot with contour lines of normalized natural frequency versus crack location and
crack depth for third mode for crack location of 250mm and crack depth of 6mm
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From Tables 1-3, it is observed that for a crack depth of 6mm located at a distance of 250mm from
fixed end of the beam, the normalized frequencies are 0.9598 for the first mode, 0.9612 for the second mode and
0.9589 for the third mode. The contour lines with the values of 0.9598, 0.9612 and 0.9589 were retrieved from
the first three modes with the help of MINITAB software as shown in Fig.11 to Fig.13 and plotted on the same
axes as shown in Fig.14. From the Fig.14 it could be observed that there are two intersection points in the
contour lines of the first and the second modes. Consequently the contour of the third mode is used to identify
the crack location (X=250mm) and the crack depth (a=6mm), uniquely. The three contour lines gave just one
common point of intersection, which indicates the crack location and the crack depth. Since the frequencies
depend on the crack depth and location, these values can be uniquely determined by the solution of a function
having solutions one order higher (in this case, three) than the number of unknowns (in this case, two, namely
crack depth and location) to be determined. This is the reason for the requirement of three modes. If there were
more parameters that influence the response (besides the crack depth and location), then one will require more
modes to identify the unknown crack depth and crack location.
Fig.11. Frequency contour plot of mode-1 for normalized frequency 0.9598
11. Experimental investigation of crack in aluminum cantilever beam using vibrationâŠ
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Fig.12. Frequency contour plot of mode-2 for normalized frequency 0.9612
Fig.13. Frequency contour plot of mode-3 for normalized frequency 0.9589
12. Experimental investigation of crack in aluminum cantilever beam using vibrationâŠ
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V. CONCLUSIONS
Detailed experimental investigations of the effects of crack on the first three modes of vibrating
cantilever beams have been presented in this paper. From the results it is evident that the vibration behavior of
the beams is very sensitive to the crack location, crack depth and mode number. A simple method for predicting
the location and depth of the crack based on changes in the natural frequencies of the beam is also presented,
and discussed. This procedure becomes feasible due to the fact that under robust test and measurement
conditions, the measured parameters of frequencies are unique values, which will remain the same (within a
tolerance level), wherever similar beams are tested and responses measured. The experimental identification of
crack location and crack depth is very close to the actual crack size and location on the corresponding test
specimen.
The following conclusions were drawn:-
1. With the presence of crack in the beam the frequency of vibration decreases.
2. The above information can be used to predict the failure of beam as well as shaft and preventive steps
can be taken.
Fig.14. Crack identification technique by using frequency contours of the first three modes of beam (mode 1,
normalized frequency (0.9598); mode 2, normalized frequency (0.9612); and 3: mode 3, normalized frequency
(0.9589).
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