THE DYNAMIC FREQUENCIES AND SHAPES OF VIBRATIONS RESEARCH OF THE DAM OF THE CHIRKEYSKAYA HPP

2021 ◽  
pp. 75-84
Author(s):  
A. M. BAKSHTANIN ◽  
◽  
M. A. SHIRYAEVA

The purpose of the research is to monitor the amplitude-frequency characteristics on the example of the Chirkeyskaya HPP dam for further assessment of the state of hydraulic structures and hydroelectric units of the HPP, as well as to develop an automated system for seismometric control of hydraulic structures of the Chirkeyskaya HPP. The article presents the results of modeling and calculations of dynamic test data of the Chirkeyskaya HPP dam using the primary processing of measurement results to identify the quality of information processing by existing methods. The paper presents the results of measurements to create a mathematical model of the dam of the Chirkeyskaya HPP. Methods were used based on the study of the statistical characteristics of vibrations arising under the infl uence of the dynamic effects of equipment and the external environment for the experimental determination of the frequencies and modes of natural vibrations of the hydraulic structures of the Chirkeyskaya HPP. Spatial-frequency diagrams of the vibration intensity distribution in the radial direction were constructed, an algorithm was implemented to use data for both reference points when identifying natural frequencies and dam shapes, a spatial-frequency distribution diagram was constructed, averaged over two reference points, smoothed interpolated along the dam with a uniform step the conversion factor at the ridge level.

2019 ◽  
Vol 104 ◽  
pp. 02003
Author(s):  
Vladimir Marchuk ◽  
Dmitry Chernyshov ◽  
Ilya Sadrtdinov ◽  
Alexander Minaev

The paper presents the results of the studies of the probability of a “flip” of the approximating function when processing the measurement results under conditions of a priori uncertainty about the signal function and the statistical characteristics of additive noise. It is analytically proved that the confidence intervals of the probability of the absence and the presence of a “flip” are equal, which is confirmed by the experimental results. The dependences of the “flipping” of the approximating function on the sample length, the dispersion of additive noise and the rate of change of the function itself are obtained.


2021 ◽  
Vol 2142 (1) ◽  
pp. 012009
Author(s):  
B B Koshoeva ◽  
N I Mikheeva ◽  
D I Mikheev ◽  
A T Bakalova

Abstract The article provides an overview of modern methods and devices for measuring water flow in open channels and natural watercourses, reflects the shortcomings and errors in their application. Considered the possibility of using the Arduino element base for creating an automated system for metering water consumption in an open stream and sending data via a Bluetooth module. Has been investigated the eventuality of using the pipe sensor YF-S201 for measuring the flow rate of liquid, in conjunction with the ultrasonic sensor of distance HC-SR04 for determining the level of water in the flow. The results of the experiment carried out on the basis of the laboratory stand “Hydraulic structures” in KSTU are presented. There were performed processing of the measurement results on the basis of the Arduino UNO board and a laptop, as well as remote data transmission and their visualization on a smartphone. The absolute and relative errors of the proposed system have been calculated.


2021 ◽  
Vol 1 ◽  
pp. 85-92
Author(s):  
Anton V. Nikonov ◽  
Victor A. Skripnikov ◽  
Margarita A. Skripnikova

The article proposes to use high-precision trigonometric leveling when determining the deformations of hydraulic structures. The required accuracy can be ensured by measuring the excess with automated high-precision total station and observing a number of conditions. Recommendations are given for the modernization of one of the sections at the Novosibirsk hydroelectric power station. The results of field studies on the determination of the refraction coefficient by the geodetic method are presented. During a summer day (from 10 to 18 hours), a change in the coefficient of refraction was recorded in the range from -0.14 to +0.81, which significantly differs from the standard value of +0.13. Therefore, when measuring the vertical displacements of deformation marks located on the alignment, it is proposed to periodically determine the coefficient of refraction and, if necessary, introduce appropriate corrections into the measurement results.


2015 ◽  
Vol 3 (1-2) ◽  
pp. 68-76
Author(s):  
Eszter Horvath-Kalman

Abstract The study is about the general genesis process of overconsolidated soils, as well as the effects of the overconsolidated ratio to structures. It will demonstrate the possible methods for the determination of the values of overconsolidated ratio and of earth pressure at rest and of the other soil-physical parameters; further, the processing of measurement results, through which the values of OCR (Overconsolidated ratio) and of λ0 (Earth pressure at rest) and of c, E soil-physical parameters (friction angles, cohesion and Young modulus) in the Kiscelli Clay Marl have been determined by Selfboring Pressuremeter.


Author(s):  
David A. Grano ◽  
Kenneth H. Downing

The retrieval of high-resolution information from images of biological crystals depends, in part, on the use of the correct photographic emulsion. We have been investigating the information transfer properties of twelve emulsions with a view toward 1) characterizing the emulsions by a few, measurable quantities, and 2) identifying the “best” emulsion of those we have studied for use in any given experimental situation. Because our interests lie in the examination of crystalline specimens, we've chosen to evaluate an emulsion's signal-to-noise ratio (SNR) as a function of spatial frequency and use this as our critereon for determining the best emulsion.The signal-to-noise ratio in frequency space depends on several factors. First, the signal depends on the speed of the emulsion and its modulation transfer function (MTF). By procedures outlined in, MTF's have been found for all the emulsions tested and can be fit by an analytic expression 1/(1+(S/S0)2). Figure 1 shows the experimental data and fitted curve for an emulsion with a better than average MTF. A single parameter, the spatial frequency at which the transfer falls to 50% (S0), characterizes this curve.


2015 ◽  
Vol 72 (2) ◽  
pp. 123-131 ◽  
Author(s):  
Marko Igic ◽  
Nebojsa Krunic ◽  
Ljiljana Aleksov ◽  
Milena Kostic ◽  
Aleksandra Igic ◽  
...  

Background/Aim. The vertical dimension of occlusion is a very important parameter for proper reconstruction of the relationship between the jaws. The literature describes many methods for its finding, from the simple, easily applicable clinically, to quite complicated, with the use of one or more devices for determination. The aim of this study was to examine the possibility of determining the vertical dimension of occlusion using the vocals ?O? and ?E? with the control of values o btained by applying cognitive functions. Methods. This investigation was performed with the two groups of patients. The first group consisted of 50 females and 50 males, aged 18 to 30 years. In this group the distance between the reference points (on top of the nose and chin) was measured in the position of the mandible in the vertical dimension of occlusion, the vertical dimension at rest and the pronunciation of the words ?OLO? and ?ELE?. Checking the correctness of the particular value for the word ?OLO? was also performed by the phonetic method with the application of cognitive exercises when the patients counted from 89 to 80. The obtained difference in the average values i n determining the vertical dimension of occlusion and the ?OLO? and ?ELE? in the first group was used as the reference for determining the vertical dimension of occlusion in the second group of patients. The second group comprised of 31 edentulous persons (14 females and 17 males), aged from 54 to 85 years who had been made a complete denture. Results. The average value obtained for the vertical dimension of rest for the entire sample was 2.16 mm, for the word ?OLO? for the entire sample was 5.51 mm and for the word ?ELE? for the entire sample was 7.47 mm. There was no statistically significant difference between the genders for the value of the vertical dimension at rest, ?ELE? and ?OLO?. There was a statistically significant difference between the values f or the vertical dimension at rest, ?OLO? and ?ELE? for both genders. There was a statistically significant correlation between the value for the vertical dimension at rest, ?OLO? and ?ELE?, for both groups of subjects. Conclusion. Determining the vertical dimension of occlusion requires 5.5 mm subtraction from the position of the mandible in pronunciation of the word ?OLO? or 7.5 mm in pronunciation of the word ?ELE?.


2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Nathan Moles

PurposeConventional approaches to digital preservation posit that archives should define a Designated Community, or future user group, for whom they preserve digital information. Archivists can then use their knowledge of these users as a reference to help them deliver digital information that is intelligible and usable. However, this approach is challenging for archives with mandates to serve wide and diverse audiences; these archives risk undermining their efforts by focusing on the interests of a narrow user group.Design/methodology/approachA unique approach to this challenge was developed in the context of a project to build a digital preservation program at the Ontario Jewish Archives (OJA). It draws from previous research on this topic and is based on a combination of practical and theoretical considerations.FindingsThe approach described here replaces the reference of a Designated Community with three core components: a re-articulation of the Open Archival Information System (OAIS) mandatory responsibilities; the identification of three distinct tiers of access for digital records; and the implementation of an access portal that allows digital records to be accessed and rendered online. Together with supplemental shifts in reference points, they provide an alternative to the concept of a Designated Community in the determination of preservation requirements, the identification of significant properties, the creation of Representation Information and in the evaluation of success.Originality/valueThis article contributes a novel approach to the ongoing conversation about the Designated Community in digital preservation, its application and its limitations in an archival context.


2021 ◽  
pp. 9-15
Author(s):  
ALEKSEI S. DOROKHOV ◽  

Research on the development of an automatic control system for the rolling-in working units is aimed at establishing the reliability and analytical relationships, determining the quality indicators of work in real conditions of the rolling-in working units of a seeding machine, and checking the patterns obtained in the fi eld and identifi ed theoretically. Research on the development of an automatic control system for the rolling implements was carried out when sowing dragee seeds of table beet of the Bordeaux variety with a seeding unit consisting of a Belarus-4235 tractor and a Monopil S15/12 precision seeding machine. The system for automatic control of soil density includes the main hardware and software: actuators for maintaining and deepening the rolling working units, microcontrollers, motor drivers, a non-contact ultrasonic sensor, a power supply unit and a sensor for measuring soil density. The paper presents the results of a study to determine the soil density when sowing seeds of table beet, depending on the moisture content of the soil in the sowing layer. The authors describe research methodology, provide graphical relationships between changes in soil density and the depth of seeding, and comment on the main obtained statistical characteristics of the experiment. As a result of the study, structural, echnological and functional diagrams of a rolling rink with an automatic control system using electronically controlled electric cylinders (linear actuators) have been developed. The optimal parameters of the linear drive of the press roller have been established: power - 50W, power supply - 12V, rod stroke - 200…600 mm, speed - 10…45 mm/s, load - 200…900 N. Experimental studies have shown the applicability of the presented system of the automatic control of soil density, which ensures the optimum density of the seedbed of 1.3…1.4 g/cm³. The described technique can be used to develop a soil density control system when sowing seeds of other vegetable crops.


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