Identification of Parametric and Momentary Damages on the Basis of Lindeberg-Levy’s Model

2017 ◽  
Vol 260 ◽  
pp. 249-257
Author(s):  
Paweł Lindstedt ◽  
Tomasz Sudakowski
Keyword(s):  
Standard Deviation ◽  
Threshold Value ◽  
Technical Condition ◽  
Technical Object ◽  
Reliability Parameters ◽  
Innovative Method ◽  
Condition Equation ◽  
Lévy’S Theorem ◽  
The Moment ◽  
Damage Map

Article presents the innovative method for the assessment of reliability condition of the exploited system, based on the appropriate analysis of changes in the current parameters of technical condition aRb and the regulation condition aRc, determined from the compressed condition equation (1 and 2). While analyzing the course of momentary parameters for technical condition aRb and the regulation condition aRc, it was observed that the parametric and momentary damages can be identified on the basis of quantitative relations between momentary threshold value dpr and corresponding momentary permissible value dprdop, which are calculated from equation (7, 8, 9) resulting from Lindeberg-Levy’s theorem. It is assumed that the damages are prevailing, when for the moment θi: dpri>dpr dopi. With the number of damages (damage map), reliability parameters for each moment of exploitation of technical object (before the catastrophic damages will occur) can be determined. Parametric damages (expected lifetime E(T) and standard deviation of expected lifetime σE(T) provides the reasonable information for the appropriate planning of the servicing of exploitative objects.

scholarly journals The New Approach to Identification of Parametric and Momentary Damages on the Basis of Lindeberg – Levy’s Model

2017 ◽  
Vol 43 (1) ◽  
pp. 5-21
Author(s):  
Paweł Lindstedt ◽  
Tomasz Sudakowski ◽  
Artur Kułaszka
Keyword(s):  
Standard Deviation ◽  
Threshold Value ◽  
Technical Condition ◽  
Technical Object ◽  
New Approach ◽  
Reliability Parameters ◽  
Condition Equation ◽  
Lévy’S Theorem ◽  
The Moment ◽  
Damage Map

Abstract The new approach for the assessment of reliability condition of the exploited system, based on the appropriate analysis of changes in the current parameters of technical condition aRb and the regulation condition aRc, determined from the compressed condition equation (1 and 2). While analyzing the course of momentary parameters for technical condition aRb and the regulation condition aRc, it was observed that the parametric and momentary damages can be identified on the basis of quantitative relations between momentary threshold value dpr and corresponding momentary permissible value dpr dop, which are calculated from equation (7, 8, 9) resulting from Lindeberg–Levy’s theorem. It is assumed that the damages are prevailing, when for the moment θi: >dpri> dpr dopi. With the number of damages (damage map), reliability parameters for each moment of exploitation of technical object (before the catastrophic damages will occur) can be determined. Parametric damages (expected lifetime E(T) and standard deviation of expected lifetime σE(T) provides the reasonable information for the appropriate planning of the servicing of exploitative objects.

scholarly journals Parametric evaluation of the technical object suitability based on analyze the quality of its maintenance and use taking into account the initial conditions

2018 ◽  
Vol 182 ◽  
pp. 01006
Author(s):  
Rafał Grądzki
Keyword(s):  
Equations Of State ◽  
Initial Conditions ◽  
Technical Condition ◽  
Operation Condition ◽  
Technical Object ◽  
Coupled Equations ◽  
Reliability Parameters ◽  
Operation Conditions ◽  
Operational Data

In this paper, the comparison of three various technical objects (engines of public transport buses) exploitation research for different initial conditions are presented. Object researches were carried out in 2012 and then repeated in 2013. Gathered operational data is presented in three sets (1 – concerning object, 2 – concerning driving conditions, 3 – concerning driver, where set 1 is the collection of diagnostic information Dk, and sets 2 and 3 are the information about object environment U) in form of conventional points (experts numerical assessments). Relation between point information of object and point information of environment was described by coupled equations of state (describing relations between operation condition and technical condition including initial conditions for each analyzed exploitation period). That method allows to determine parameters of technical condition aT and operation condition aR and next, from the course of aT parameter, set of parametrical damage mT(t) and from course of parameter aR – set of momentary damage aR(t). Thus it is possible to evaluate exploitation, technical and operation conditions of each object (bus engine). Received reliability parameters allows to properly control exploitation and service of particular objects and set of objects (fleet of buses) and its elements.

The Method of Complex Worthiness Assessment of an Engineering Object in the Process of its Use and Service

2008 ◽  
Vol 144 ◽  
pp. 45-52 ◽  
Author(s):  
Paweł Lindstedt
Keyword(s):  
Threshold Value ◽  
State Equation ◽  
Technical Condition ◽  
Complex Method ◽  
Technical Object ◽  
Common Information ◽  
Maintenance Practice ◽  
Condition Adjustment ◽  
Theoretical Foundations

A focus of the paper is concerned with the issue that optimal actions of regulation, diagnostics and reliability tests of technical objects are required from the maintenance staff involved in their use and servicing, and on the other hand, that they are performed independently and autonomously in the current maintenance practice instead of being accomplished in a strictly coordinated and complex way. It was noticed that only one and common information on the object exists and provides a solid basis for coordination of the regulation, diagnostics and reliability tests. This information can be applied many times for solving various problems no matter if they concern regulation, diagnostics or reliability. Next, this paper presents an original approach of conversion of the considered information into explicit time-and-space determined “number of threshold value overshoots” of signals related to the object and its environment as well as theoretical foundations (based on various configurations of the state equation) for conversion of the considered piece of information, expressed by the aforementioned “numbers”, into the parameters of the object ability condition (i.e., its technical condition, adjustment and reliability). The theses of the presented complex method for the assessment of technical object ability were subjected to long-term verification with positive result in the study of the Allison 250 engine bearing system.

scholarly journals Analysis of storm water systems and sanitary sewers: technical, organizational and economic aspects

2018 ◽  
Vol 5 (3) ◽  
Author(s):  
Viktoriia Vorobiyova ◽  
Galina Astratova
Keyword(s):  
Wastewater Treatment ◽  
Local Treatment ◽  
Technical Condition ◽  
Water Supply Systems ◽  
Economic Aspects ◽  
Highly Qualified ◽  
Qualified Personnel ◽  
Systems Identification ◽  
Treatment Facilities ◽  
The Moment

The analysis of systems of storm and household Sewerage on the basis of research of some technical, organizational and economic aspects of activity of systems is carried out. It is shown that at the moment the problem of wastewater treatment is extremely relevant. It is established that many companies discharge a large amount of waste water, which is not actually treated in local reservoirs. It is revealed that in the studied area in the Russian Federation as a whole and in the Sverdlovsk region, in particular, there is a failure to comply with the standards of treatment facilities. The key reasons for this situation are the following main factors: physical deterioration of the equipment, unsatisfactory technical condition of treatment facilities; mismatch of the composition of incoming wastewater and treatment systems; lack of wastewater treatment facilities; under-load on hydraulics and uneven flow of wastewater; violation of technical and technological modes of operation of treatment facilities; untimely carrying out of repair and restoration works, replacement of the failed equipment, units and parts; lack of sufficient financing of the industry, financing on the «residual principle»; lack of highly qualified personnel for the implementation of competent operation of treatment facilities; etc. The authors believe that in order to improve the quality of wastewater discharged, reduce their impact on water bodies, reduce the volume of wastewater emissions, the following priority measures are needed: construction of new, reconstruction and expansion of existing treatment facilities; construction of local treatment facilities, post-treatment units; commissioning of recycling and re-water supply systems; identification of additional sources of financing for the treatment facilities system, including through concession agreements, the creation of private-public partnerships; formation of «the state order» and allocation of target budgetary places in colleges and higher education institutions on training in the specialties connected with housing and communal services, water consumption and water disposal.

scholarly journals Forecast model for estimating the service life of a diagnosed object based on the Neyman–Pearson method

2018 ◽  
Vol 216 ◽  
pp. 03011
Author(s):  
Sergey Barsukov ◽  
Sergey Pakhomov
Keyword(s):  
Service Life ◽  
Power Transformer ◽  
Impurity Content ◽  
Forecast Model ◽  
Threshold Value ◽  
Technical Condition ◽  
Transformer Oil ◽  
Average Risk ◽  
Iron Impurity ◽  
Object Based

The paper is aimed at developing a forecast model for estimating the service life of a diagnosed object based on the Neyman–Pearson method. It presents a procedure for selecting necessary and sufficient number of diagnostic indicators using the forecast model. The technique has been tested on the basis of a power transformer with a liquid dielectric. A condition-based operation strategy has been proposed for the transformer. According to this strategy, the iron impurity content in the dielectric liquid (oil) of the transformer should be measured every year of operation. Based on the forecast model, it is possible to calculate the variation of average risk (R) and a threshold value of iron impurity content in the transformer oil (k0) for each year of operation. Using these parameters, a reliable forecast model can be constructed to estimate the remaining service life of the transformer. The obtained relationships make it possible to identify a scientifically grounded stage in the service life of a diagnosed object, at which the number of measurable diagnostic indicators (indicators that are necessary for assessing the real technical condition of equipment) can be minimized.

Monitoring of the technical condition of tracks based on machine learning

2019 ◽  
Vol 234 (7) ◽  
pp. 702-708
Author(s):  
Bartosz Firlik ◽  
Maciej Tabaszewski
Keyword(s):  
Machine Learning ◽  
Threshold Value ◽  
Technical Condition ◽  
Learning System ◽  
Mean Square ◽  
Vibration Acceleration ◽  
Vehicle Velocity ◽  
Track Condition ◽  
The Cost ◽  
The Impact

This paper presents the concept of a simple system for the identification of the technical condition of tracks based on a trained learning system in the form of three independent neural networks. The studies conducted showed that basic measurements based on the root mean square of vibration acceleration allow for monitoring the track condition provided that the rail type has been included in the information system. Also, it is necessary to select data based on the threshold value of the vehicle velocity. In higher velocity ranges (above 40 km/h), it is possible to distinguish technical conditions with a permissible error of 5%. Such selection also enables to ignore the impact of rides through switches and crossings. Technical condition monitoring is also possible at lower ride velocities; however, this comes at the cost of reduced accuracy of the analysis.

scholarly journals IX. Mathematical contributions to the theory of evolution.—XIX. Second supplement to a memoir on skew variation

1916 ◽  
Vol 216 (538-548) ◽  
pp. 429-457 ◽  
Keyword(s):  
Standard Deviation ◽  
Homogeneous Material ◽  
Fourth Moment ◽  
Frequency Distributions ◽  
Theory Of Evolution ◽  
Theoretical Frequency ◽  
Moment Coefficient ◽  
The Mean ◽  
The Moment ◽  
True Values

In a memoir presented to the Royal Society in 1894, I dealt with skew variation in homogeneous material. The object of that memoir was to obtain a series of curves such that one or other of them would agree with any observational or theoretical frequency curve of positive ordinates to the following extent :—(i) The areas should be equal; (ii) the mean abscissa or centroid vertical should be the same for the two curves; (iii) the standard deviation (or, what amounts to the same thing, the second moment coefficient) about this centroid vertical should be the same, and (iv) to (v) the third and fourth moment coefficients should also be the same. If μ s be the s th moment coefficient about the mean vertical, N the area, x ¯ be the mean abscissa, σ = √ μ 2 the standard deviation, β 1 = μ 3 2 / μ 2 3 , β 4 = μ 4 / μ 2 2 , then the equality for the two curves of N, x ¯ , σ, β 1 and β 2 leads almost invariably in the case of frequency to excellency of fit. Indeed, badness of fit generally arises from either heterogeniety, or the difficulty in certain cases of accurately determining from the data provided the true values of the moment coefficients, e. g ., especially in J- and U-shaped frequency distributions, or distributions without high contact at the terminals ; here the usual method of correcting the raw moments for sub-ranges of record fails. Having found a curve which corresponded to the skew binomial in the same manner as the normal curve of errors to the symmetrical binomial with finite index, it occurred to me that a development of the process applied to the hypergeometrical series would achieve the result I was in search of, i. e ., a curve whose constants would be determined by the observational values of N, x ¯ , σ, β 1 and β 2 .

scholarly journals The possibility of an extension to the floor of a non-residential building using lightweight structural elements of increased rigidity

2019 ◽  
Vol 7 (1) ◽  
pp. 28-33
Author(s):  
Ольга Хрянина ◽  
Ol'ga Hryanina ◽  
Юсеф Янгуразов ◽  
Yousef Yangurazov
Keyword(s):  
Residential Building ◽  
Technical Condition ◽  
Structural Elements ◽  
Main Bearing ◽  
Extensive Experience ◽  
Satisfactory Condition ◽  
Test Conditions ◽  
Small Cracks ◽  
The Moment ◽  
Storey Building

The authors summarized the extensive experience of reconstruction of buildings taking into account the superstructure. A visual full-scale inspection of the actual technical condition of the main bearing and enclosing structures of a non-residential one-storey building was carried out. The possibility of superstructure on the floor of the building using lightweight structural elements of high rigidity is considered. According to the results of the survey, an assessment of the technical condition of the structures is given. The General satisfactory condition of the foundations, walls, internal supports, building covering was revealed. Unacceptable deflections of plates, cracks in the plates and between them are not fixed. However, in the wall at row G has haphazardly small cracks on external verst masonry, which appeared likely to result from the soaking of the masonry from leaks from the roof and changes in temperature and humidity. At the moment, the cracks have stabilized, the leaks have been eliminated. The calculations of the foundations of the test conditions of the stress under the foot and stress check given add-in. Conclusions and recommendations are formulated. For the wall on the axis G in the process of construction and operation must be monitored. In case of activation of development of constructive cracks to solve a question of possible strengthening.

scholarly journals System of Remote Monitoring of Technical Objects

2021 ◽  
Vol 18 (5) ◽  
pp. 110-121
Author(s):  
A. A. Korotky ◽  
A. A. Demyanov ◽  
A. A. Demyanov
Keyword(s):  
Online Monitoring ◽  
Adaptive System ◽  
Residual Life ◽  
Technical Condition ◽  
Transport Processes ◽  
Rolling Stock ◽  
Diagnostic Process ◽  
Online Information ◽  
Technical Object ◽  
Technical Parameters

Currently, digitalization, being implemented in all spheres of human activity, including transport processes, requires efficiency in obtaining and processing information, as well as timeliness of decisions made on its basis. The modern system of operation of railway traction rolling stock is characterized by the lack of online information about the current technical condition and the residual life of its components for decision making.The article proposes to solv e the problem by implementing an adaptive system for remote online monitoring of technical parameters of operated objects into the field of traction rolling stock operation. The adaptive system contains software related to recommendation decision support systems. A distinctive feature of the system is the presence of elements of artificial intelligence, which self-learns by combinatorial processing of the historical database on operation of this or a similar technical object and current performance indicators corresponding to them.The proposed information processing algorithm is versatile and, in principle, can work with a variety of data sources, including existing traction rolling stock safety devices. Online monitoring of technical parameters of operated objects can be extended to both cargo-passenger rolling stock and related auxiliary machinery and devices (track machines, cranes, hump retarders, etc.). Based on the analysis of the information received, the software generates and transmits recommendations regarding current urgent actions for managing staff and maintenance personnel.In addition, the proposed technology makes it possible to predict indicators of accidents at operated objects in real time, providing an opportunity to facilitate the diagnostic process, optimize organisation of maintenance, reduce the cost of maintaining rolling stock, and increase safety of the transportation process.The adaptive system of remote online monitoring of operational safety of technical objects, considered in the article, through a risk-based approach, is a unique development that has no analogues. 

scholarly journals RESEARCH AND EVALUATION OF FUNCTIONAL PARAMETERS OF LOW VOLTAGE DEVICES

2018 ◽  
Vol 20 (5-6) ◽  
pp. 13-21
Author(s):  
E. Gracheva ◽  
A. Safin ◽  
R. Sadykov
Keyword(s):  
Contact Resistance ◽  
Low Voltage ◽  
Experimental Studies ◽  
Threshold Value ◽  
Probability Of Failure ◽  
Technical Condition ◽  
Operating Conditions ◽  
Switching Device ◽  
Predicting Performance ◽  
Complete Contact

To assess the operability and technical condition of low-voltage devices, it is proposed to use the resistance of contact connections. The probability of failure-free operation is proposed to be evaluated by the dependence of the resistance of the contact connections of the apparatus on the number of switching operations. As a result of wear, the initial value of the contact resistance of the switching device increases and reaches a critical value at which the switching device fails. Due to the fact that in the process of research there are both complete contact failures and short-term switching of only one time, the contact resistance is exceeded by the contact resistance of the threshold value. For magnetic starters, circuit breakers and contactors, based on the results of the experimental studies carried out, in order to achieve the critical resistance value of the apparatus, аn average of three times the initial resistance. At the same time, the quantitative characteristics of the functioning efficiency are determined by the methods of probability theory and mathematical statistics. The set of the obtained quantitative indicators allows to determine the actual level of reliability of contacting, and also extends the possibility of predicting performance ratings in the design.  In the present article, a method for the complex evaluation of the efficiency of low-voltage apparatus has been developed and the laws of the change in the resistance of contact connections and the probability of failure-free operation of low-voltage switching devices have been revealed, depending on the operating conditions.

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