Energy of Vibroacoustic Signal as Parameter of Logistics Model of the Tooth’s Crack Development

2012 ◽  
Author(s):  
Stanisław Radkowski ◽  
Robert Gumiński
Keyword(s):  
Probability Distribution ◽  
Statistical Methods ◽  
Fatigue Damage ◽  
Technical Condition ◽  
Diagnostic Information ◽  
Crack Development ◽  
Vibroacoustic Signal ◽  
Damage Process ◽  
Cracks Propagation ◽  
Development Phases

The paper takes on the issue of uncertainty in statistical methods of cracks propagation. The goal of the paper was to develop a method, which would enable use of diagnostic information in assessment of fatigue damage process. Particular attention was paid to the possibility of forecasting the occurrence of damage due to fatigue while relying on the analysis of the structure of a vibroacoustic signal. The difficulty in this case is that the set of parameters containing diagnostic information may change as defects develop. This fact confirms the necessity of examining the evolution of probability distribution and defining the periods of an object’s operation, carried out while taking into account the actual technical condition as well as the associated identification of defect development phases. The study presents the following issue: developing the method of diagnosing the early stages of defect development while analyzing energy of vibroacoustics signal as parameter of logistics model of cracks development.

Using the Three-Stage Weibull Equation and Tree-Based Model to Characterize the Mix Fatigue Damage Process

2005 ◽  
Vol 1929 (1) ◽  
pp. 227-237 ◽  
Author(s):  
Bor-Wen Tsai ◽  
John T. Harvey ◽  
Carl L. Monismith
Keyword(s):  
Crack Initiation ◽  
Fatigue Damage ◽  
Fatigue Tests ◽  
Fatigue Performance ◽  
Data Set ◽  
Warm Up ◽  
Weibull Parameters ◽  
Damage Process ◽  
Initiation Stage ◽  
Weibull Equation

The primary purpose of this paper is to demonstrate the applicability of the three-stage Weibull equation to describe the fatigue damage process using flexural controlled deformation fatigue tests. A data set of 179 beam fatigue tests originally designed for exploring the fatigue performance of conventional dense graded asphalt concrete (DGAC) and asphalt–rubber hot-mix gap-graded (ARHM-GG) mixes was used to inspect the three-stage Weibull parameters that were estimated using a genetic algorithm. The tree-based regression–category models were then used to uncover the data structure of the estimated parameters as a function of material properties, conditioning methods, temperatures, compaction methods, and strain levels. In general, the three-stage Weibull equation provides satisfactory fitting results for the three-stage fatigue damage process occurring in a beam test. It was found that the tree-based models of three-stage Weibull parameters associated with the crack initiation stage were statistically adequate and reliable compared with the models of parameters related to the warm-up stage and the crack propagation stage. It might suggest that these crack initiation parameters are better indexes to assess the fatigue performance.

2834 The fatigue damage process of CVD diamond film on substrate

2007 ◽  
Vol 2007.1 (0) ◽  
pp. 723-724
Author(s):  
Hitoshi SEKINO ◽  
Shoji KAMIYA ◽  
Hiroyuki HANYU ◽  
Catarina Joana Madaleno ◽  
Gil Cabral ◽  
...  
Keyword(s):  
Fatigue Damage ◽  
Diamond Film ◽  
Cvd Diamond ◽  
Damage Process ◽  
Cvd Diamond Film

OS2503 EBSD observation and Strain Evaluation for Creep-fatigue Damage Process of Mod.9Cr Steel

2011 ◽  
Vol 2011 (0) ◽  
pp. _OS2503-1_-_OS2503-3_
Author(s):  
Shotaro OGINO ◽  
Hiroyuki HAGIWARA ◽  
Toshiki TSUBOI ◽  
Kazunari FUJIYAMA ◽  
Hirohisa KIMACHI
Keyword(s):  
Fatigue Damage ◽  
9Cr Steel ◽  
Creep Fatigue ◽  
Damage Process

GENERALIZED MEASURE OF UNCERTAINTY AND THE MAXIMIZABLE ENTROPY

2010 ◽  
Vol 24 (09) ◽  
pp. 825-831 ◽  
Author(s):  
CONGJIE OU ◽  
AZIZ EL KAABOUCHI ◽  
JINCAN CHEN ◽  
ALAIN LE MÉHAUTÉ ◽  
ALEXANDRE QIUPING WANG
Keyword(s):  
Distribution Function ◽  
Probability Distribution ◽  
Statistical Methods ◽  
Physical Meaning ◽  
Probability Distribution Function ◽  
Random Variable ◽  
Uncertainty Measure ◽  
Definition Of ◽  
Measure Of Uncertainty

For a random variable x we can define a variational relationship with practical physical meaning as [Formula: see text], where I is the uncertainty measure. With the help of a generalized definition of expectation, [Formula: see text], we can find the concrete forms of the maximizable entropies for any given probability distribution function, where g({pi}) may have different forms for different statistical methods which include the extensive and non-extensive statistics. Moreover, it is pointed out that this generalized uncertainty measure is valid not only for thermodynamic systems but also for non-thermodynamic systems.

scholarly journals Information Value Measure for Optimization of Flexible Diagnosis Programs of Technical Objects

2019 ◽  
Vol 18 (6) ◽  
pp. 1434-1461 ◽  
Author(s):  
Evgeniy Kopkin ◽  
Igor Kobzarev
Keyword(s):  
A Priori ◽  
Technical Condition ◽  
Diagnostic Information ◽  
Information Value ◽  
Technical State ◽  
A Posteriori ◽  
Automated Systems ◽  
Maximum Value ◽  
Diagnostic Signs ◽  
The Difference

Existing methods of calculating of the value of diagnostic information circulating in the automated systems of monitoring of technical condition of objects do not take into account "losses" ("gains") resulting from making “wrong” decisions when identifying this state. The purpose of the work is to develop an algorithm that allows to solve the problem of recognizing the technical state of the object being analyzed by means of dynamic programming, the value of the diagnostic information as an optimized indicator being used. The solution to the optimization problem of a diagnostic procedure is based on the use of a measure of the information value proposed by R. L. Stratonovich. It is modified according to the subject area of the technical diagnostics and in the case when the diagnostic features presented in the form of intervals on the real numerical axis are used. The maximum value of the diagnostic information is achieved by minimizing the average "losses" (maximizing the average "gains") obtained when performing tests of diagnostic signs in the process of recognizing the technical condition of an object. To solve the problem, a recurrent expression possessing a scientific novelty has been proposed. It allows to calculate the value of the information obtained when performing tests of diagnostic signs in each of the analyzed information states of the diagnostic process. In the process of the diagnostics program implementation when recognizing the technical condition of the object both “losses” and “winnings” are possible. The difference between their a priori and a posteriori means values characterizes the value of the diagnostic information numerically. The magnitude of the information value indication depends on the probabilities of the results of the diagnostic signs checks and is proportional to the difference between the a posteriori and a priori probabilities of achieving the diagnostic goal. By using the proposed solution, it is possible to synthesize the flexible diagnostics program that is optimal according to the maximum value of diagnostic information in the form of a oriented graph or sets of tests in proper sequence of their execution. This is necessary in order to recognize the specific technical state in which the object is located. The implementation of the algorithm developed is possible in the software and algorithmic support of the automated systems for monitoring the state of complex technical objects.

scholarly journals Different Bayesian Methods for Updating the Fatigue Crack Size Distribution in a Tubular Joint

2020 ◽  
Vol 143 (2) ◽  
Author(s):  
H. Khalili ◽  
S. Oterkus ◽  
N. Barltrop ◽  
U. Bharadwaj
Keyword(s):  
Numerical Methods ◽  
Probability Distribution ◽  
Size Distribution ◽  
Fatigue Damage ◽  
Crack Size ◽  
Offshore Platforms ◽  
Additional Information ◽  
Joint Reliability ◽  
Service Lifetime ◽  
Tubular Joint

Abstract Offshore platforms are prone to fatigue damage. To evaluate the fatigue damage, these platforms are periodically inspected during the in-service lifetime. Inspection activities provide additional information, which includes detection and measurement of crack size. A Bayesian framework can be used to update the probability distribution of the uncertain parameters such as crack size. After updating the distribution of the crack size, it is possible to improve the estimation of joint reliability. The main purpose of this study is to present different methods of Bayesian inference to update the probability distribution of the crack size using the inspection results and to demonstrate how the results are different. Two different methods are presented: analytical (conjugate) and numerical methods. The advantages and shortcomings of each method are discussed. To compare the results of the analytical and numerical methods, two different situations are considered; updating the crack size distribution for a particular joint and updating the crack size distribution for several joints that have almost the same conditions. Although the proposed methodology can be applied to different kinds of structures, an example of tubular joints in a specific jacket platform is presented to demonstrate the proposed approach and to compare the results of two methods.

Mechanistic Characterization of Fatigue Damage Process and Failure Predictions of Asphalt Binders

2021 ◽  
Vol 147 (3) ◽  
pp. 04021036
Author(s):  
Weizhuo Yan ◽  
Lin Cong ◽  
Hui Li ◽  
Yuqing Zhang ◽  
Xue Luo
Keyword(s):  
Fatigue Damage ◽  
Asphalt Binders ◽  
Damage Process ◽  
Failure Predictions

scholarly journals Evaluation of the technical condition of road transport means

2018 ◽  
Vol 182 ◽  
pp. 02023
Author(s):  
Henryk Tylicki
Keyword(s):  
Fault Location ◽  
Road Transport ◽  
Technical Condition ◽  
Diagnostic Information ◽  
Diagnostic Parameters ◽  
The Status ◽  
Observation Matrix ◽  
Binary Observation ◽  
Location Test

The paper presents the methodology for determining the procedures of the condition and fault location test, using logical relations (0,1) between diagnostic parameters and technical conditions of the means of transport in the form of a binary observation matrix, determination of the status control and fault location test and use of diagnostic information received during use of means of transport. Implementation of the proposals included in the study should increase the efficiency of diagnosing means of transport, and thus contribute to activities that rationalize their exploitation.

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