scholarly journals Features of assessing the condition and behavior of low-water bridges

2021 ◽  
Vol 80 (6) ◽  
pp. 334-342
Author(s):  
A. A. Loktev ◽  
V. V. Korolev ◽  
I. V. Shishkina
Keyword(s):  
The State ◽  
Structural Elements ◽  
Natural Vibrations ◽  
Water Bridge ◽  
Viscoelastic Dampers ◽  
Bridge Span ◽  
Proposed Model ◽  
And Behavior ◽  
Bearing Part ◽  
Water Bridges

The article describes features of operation and monitoring of low-water bridges, which are found on highways of regional, intermunicipal and local importance. Vibrations of the bridge span are considered in detail, taking into account its interaction with other structural elements and the environment. As a characteristic, the change of which takes into account the change in the state of the bridge structure, it is proposed to use the frequency of natural vibrations. To simulate the dynamic effects of transport and the dynamic behavior of individual elements and the entire structure as a whole, it is proposed to use viscoelastic elements of the Kelvin–Voigt type. When solving the problem, an approach has been implemented that makes it possible to take into account the anisotropic properties of the superstructure associated with various reinforcement along and across the roadway of the bridge, and to present the design scheme of the span not in the form of a beam supported at the edges with the help of hinges or viscoelastic dampers, but in the form of a plate, which can have different fxing conditions along the entire contour. The use of the proposed model and approach will make it possible to obtain the necessary data on the state of low-water bridges, for which there is often no possibility of visual inspection or instrumental inspection from the lower side of the bearing part of the superstructure. By the values of the frequency of natural vibrations, it is possible to estimate the water level above the low-water period and predict food situations, during which the roadway of the low-water bridge may be fooded.

Formation Of An Estimate For A State Contract With A Firm Price In The Construction Sector

2020 ◽  
pp. 47-57
Keyword(s):  
Construction Projects ◽  
Cost Of Capital ◽  
Federal Budget ◽  
The State ◽  
Structural Elements ◽  
Construction Sector ◽  
Construction Process ◽  
Practical Application ◽  
Stage Of Development ◽  
Capital Construction

The issues of determining the estimated cost of capital construction projects with the involvement of Federal budget funds at the stage of development of project documentation, during verification of the accuracy of determining the estimated cost and the initial (maximum) contract price are considered. On the basis of the assessment of amendments to urban planning legislation for the purpose of implementing a state contract by the contractor ( based on the results of competitive procedures or without competitive procedures by decision of state authorities), the procedure for forming the estimate as part of a state (municipal) contract, the price of which is firm, is presented. For the purpose of mutual settlements between the customer and the contractor for the work performed, the formation of primary accounting documentation, as well as for checking the work performed by regulatory authorities, an example of drawing up an estimate of the state (municipal) contract on the basis of grouping costs according to structural elements and complexes of work is given. The result of the research conducted was the development of regulations and the formation of criteria for their practical application by state bodies, institutions, organizations and other participants in the investment-construction process, as well as recipients of budget funds, who perform the functions of the state (municipal) customer, developer and technical customer.

The concept of development of the Contract System of the Ministry of Internal Affairs of Russia as a tool for effective use of budget funds and ensuring competition in the state procurement market

2021 ◽  
pp. 76-87
Author(s):  
A. A. Tsviliy-Buklanova
Keyword(s):  
Public Procurement ◽  
The State ◽  
Regulatory Framework ◽  
Structural Elements ◽  
Departmental Level ◽  
Internal Affairs ◽  
Effective Use ◽  
And Control

The article is devoted to the relevance of the development and adoption of the Concept for the development of the Contract System of the Ministry of Internal Affairs of Russia in order to increase the efficiency of using budget funds and eliminate corruption risks in the implementation of public procurement. The regulatory framework of federal and departmental level was considered, attention was paid to practical aspects of procurement of goods, works and services for the needs of internal affairs bodies, issues of regulation and control are reflected. Structural elements of the Concept, ways to improve the Contract System of the Ministry of Internal Affairs of Russia are proposed.

A Taxonomic Revision of the Genus Megetra (Coleoptera: Meloidae) with Ecological and Behavioral Notes

1965 ◽  
Vol 97 (6) ◽  
pp. 561-580 ◽  
Author(s):  
Richard B. Selander
Keyword(s):  
New Species ◽  
New Mexico ◽  
Intraspecific Variation ◽  
North American ◽  
Taxonomic Revision ◽  
Seasonal Distribution ◽  
The State ◽  
Northern Arizona ◽  
The North ◽  
And Behavior

Abstract>Three species are recognized in the North American genus Megetra LeConte. The most distinctive of these anatomically and ecologically is M. cancellata (Brandt and Erichson), which ranges discontinuously from Arizona and New Mexico to the state of Hidalgo in México and occurs in limited sympatry with both of its congeners. Megetra vittata (LeConte) ranges from northern Arizona to western Texas. It appears to be strictly allopatric with, and similar ecologically to, M. punctata, new species, which ranges from southern Arizona and New Mexico to Durango, México. Specific diagnoses are made on the basis of characters of adult and, for M. cancellata and M. punctata, larval anatomy. Intraspecific variation in several adult characters is analyzed. Notes on the seasonal distribution, habitat, and behavior of the adult beetles are included.

scholarly journals Spatial regression methods to evaluate beekeeping production in the state of Rio de Janeiro

2013 ◽  
Vol 65 (2) ◽  
pp. 553-558
Author(s):  
W.S. Tassinari ◽  
M.C. Lorenzon ◽  
E.L. Peixoto
Keyword(s):  
Rio De Janeiro ◽  
High Performance ◽  
Spatial Regression ◽  
The State ◽  
Spatial Effects ◽  
Regression Methods ◽  
Honey Production ◽  
Production Factors ◽  
Proposed Model ◽  
Wild Vegetation

Brazilian beekeeping has been developed from the africanization of the honeybees and its high performance launches Brazil as one of the world´s largest honey producer. The Southeastern region has an expressive position in this market (45%), but the state of Rio de Janeiro is the smallest producer, despite presenting large areas of wild vegetation for honey production. In order to analyze the honey productivity in the state of Rio de Janeiro, this research used classic and spatial regression approaches. The data used in this study comprised the responses regarding beekeeping from 1418 beekeepers distributed throughout 72 counties of this state. The best statistical fit was a semiparametric spatial model. The proposed model could be used to estimate the annual honey yield per hive in regions and to detect production factors more related to beekeeping. Honey productivity was associated with the number of hives, wild swarm collection and losses in the apiaries. This paper highlights that the beekeeping sector needs support and help to elucidate the problems plaguing beekeepers, and the inclusion of spatial effects in the regression models is a useful tool in geographical data.

scholarly journals Condensation method in practical modal analysis of hull vibration with application of 3D FE model

2019 ◽  
pp. 162-169
Author(s):  
Valeriy Sutyrin
Keyword(s):  
Modal Analysis ◽  
Three Dimensional ◽  
Element Model ◽  
Fe Model ◽  
Structural Elements ◽  
Natural Vibrations ◽  
Condensation Method ◽  
Dimensional Finite Element ◽  
Three Dimensional Finite Element ◽  
Analytical Approaches

This paper gives modal analysis results for mid-body of a refrigerator carrier ship by means of combined three-dimensional finite-element model with 1.5 million DOF. The study estimates the error of modal analysis for the ship structure if its boundary conditions are specified in advance, i.e. approximately, as well as analyses the gain in time offered by structuring the analytical model as per reduction (condensation) method. Analytical approaches thus transformed can be successfully applied in filtering lower frequencies and modes of natural vibrations for structural elements and joints of hull in the direct vicinity of exciting force application points.

scholarly journals Stage excitement as individual psychological state of the vocalist

2020 ◽  
pp. 131-134
Author(s):  
N. K. Korneev ◽  
Keyword(s):  
Individual Characteristics ◽  
Great Emphasis ◽  
The State ◽  
Psychological State ◽  
Public Performance ◽  
Emotional Component ◽  
The Individual ◽  
And Behavior

The state and behavior of a singer on the stage has not been fully explored and studied. This article is an attempt to understand the causes of such a phenomenon as the excitement of a vocalist who goes on stage and performs in front of an audience. The unusual psychological state that an artist develops on the stage during a public performance brings many unexpected «discoveries» to the performer and requires detailed study. Unlike ordinary excitement, the author designated it as «stage excitement» and pointed out the factors that lead to the occurrence of such a state. The ways of neutralizing the negative sides of the artist’s state on the stage are analyzed. A great emphasis in the work is placed on the study of the psychological portrait of the performer and the psycho-emotional component of his personality as well as the characteristic moments associated with the individual characteristics of the vocalist.

scholarly journals TREE PLANTS OF SPNA "BASHKIRTSEV'S HOUSE": STATE, VALUABLE IMPORTANCE, POSSIBILITIES OF REINTEGRATION INTO MODERN CULTURAL LIFE

2021 ◽  
Vol 10 (4) ◽  
pp. 120-141
Author(s):  
Viktor Volodin ◽  
Nikolay Kharchenko ◽  
Oleg Tregubov
Keyword(s):  
Protected Areas ◽  
Formation Process ◽  
The State ◽  
Tree Plantations ◽  
Structural Elements ◽  
Cultural Life ◽  
Main Factors ◽  
Points Of View ◽  
Natural Monument

The article analyzes the dynamics of the state of tree plantations in protected areas as a part of the historical formation process of the object. The complex of the main factors determining this dynamics has been considered. Based on the data of the study, the most valuable (from various points of view) structural elements of the investigated natural monument, including unique trees, are identified. The feasibility of the reconstruction of the object and possible approaches to it has been considered

scholarly journals ASSESSMENT OF THE STRENGTH OF A COMPOSITE PACKAGE WITH INTERNAL DEFECTS ACCORDING TO VARIOUS FAILURES CRITERIA UNDER THE INFLUENCE OF UNSTEADY LOAD

2020 ◽  
Vol 17 (35) ◽  
pp. 1218-1230
Author(s):  
Aleksandr L. MEDVEDSKIY ◽  
Mikhail I. MARTIROSOV ◽  
Anton V. KHOMCHENKO ◽  
Darina V. DEDOVA
Keyword(s):  
Polymer Composite ◽  
Longitudinal Direction ◽  
Polymer Composite Material ◽  
Aviation Industry ◽  
Structural Elements ◽  
The Finite Element Method ◽  
Fracture Criteria ◽  
Safety Factors ◽  
Elliptical Shape ◽  
And Behavior

One of the priority tasks of the modern aviation industry is to increase the economic efficiency of aircrafts. In the context of solving this problem, when creating new aircrafts, polymer composite materials (PCM) are increasingly used. Particular attention is paid to structural elements, damage to which can lead to a decrease in the strength of an airframe as a whole. Therefore, an essential task in the design, maintenance, and operation of the test is to study the effect of interlayer defects on the strength and behavior of PCM structures under the influence of unsteady loads. This work is devoted to a numerical analysis of the behavior of a plate made of a polymer composite material (PCM) under unsteady load considering interlayer defects of an elliptical shape, as well as an assessment of the strength of a composite package according to various fracture criteria. The problem is solved by the finite element method using the LS-DYNA software package. Then, using the method of mathematical modeling, the interlayer separation of an elliptical shape was analyzed, which allowed to evaluate the strength of the plate and fiber according to the criteria of Hashin, Puck, Chang-Chang, and LaRC03 and compare the results. It was found in the study, that the failure indices and safety factors, which were obtained using various criteria (Hashin and Chang-Chang), have the same distribution, since the dependence of the implemented fracture mode (fiber compression in the longitudinal direction) is identical. Analysis.

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