scholarly journals SUBSTANTIATION OF DESIGN PARAMETERS OF COAL DUST EXPLOSION CONTAINMENT SYSTEM

2021 ◽  
Vol 447 (3) ◽  
pp. 72-79
Author(s):  
V. Kostenko ◽  
O. Zavialova ◽  
S. Pozdieiev ◽  
T. Kostenko ◽  
A. Vinyukov
Keyword(s):  
Rock Mass ◽  
Mine Working ◽  
Seismic Waves ◽  
Coal Dust ◽  
Seismic Wave Propagation ◽  
Design Parameters ◽  
Qualitative And Quantitative ◽  
Seismic Sensors ◽  
Acceleration Amplitude ◽  
Quantitative Indicators

The aim of the paper is to identify the qualitative and quantitative parameters of seismic waves and accelerations on the mine working contour after an explosion of the gas-and-dust mixture. Information about the formation of seismic waves in the rock mass accommodating the mine working was received using modelling in order to improve the means of containment of explosion of further developed dust-air mixture. The parameters of seismic waves, such as propagation velocity and acceleration, amplitude, and frequency of oscillations of mine working walls, were established for the conditions of the experimental structure, which allows to scientifically substantiating the design parameters of the systems protecting the miners against explosion. The energy of the explosion propagates in the rock mass in the form of a series of peak-like pulses and oscillations with smaller amplitude. Modulus of acceleration is an informational indicator, which suits the most for registration by seismic sensors responding, specifically, to the most powerful peak pulses formed by seismic waves. By revealing the qualitative and quantitative indicators of seismic wave propagation on the mine working contour and in the rock mass, the parameters of seismic sensors of the systems protecting the miners against explosion can be substantiated.

scholarly journals Seismic wave propagation in anisotropic ice – Part 1: Elasticity tensor and derived quantities from ice-core properties

2015 ◽  
Vol 9 (1) ◽  
pp. 367-384 ◽  
Author(s):  
A. Diez ◽  
O. Eisen
Keyword(s):  
Seismic Waves ◽  
Dynamic Behaviour ◽  
Ice Core ◽  
Ice Cores ◽  
Seismic Wave Propagation ◽  
Elasticity Tensor ◽  
Reflection Coefficients ◽  
Seismic Velocities ◽  
Crystal Anisotropy ◽  
Elasticity Tensors

Abstract. A preferred orientation of the anisotropic ice crystals influences the viscosity of the ice bulk and the dynamic behaviour of glaciers and ice sheets. Knowledge about the distribution of crystal anisotropy is mainly provided by crystal orientation fabric (COF) data from ice cores. However, the developed anisotropic fabric influences not only the flow behaviour of ice but also the propagation of seismic waves. Two effects are important: (i) sudden changes in COF lead to englacial reflections, and (ii) the anisotropic fabric induces an angle dependency on the seismic velocities and, thus, recorded travel times. A framework is presented here to connect COF data from ice cores with the elasticity tensor to determine seismic velocities and reflection coefficients for cone and girdle fabrics. We connect the microscopic anisotropy of the crystals with the macroscopic anisotropy of the ice mass, observable with seismic methods. Elasticity tensors for different fabrics are calculated and used to investigate the influence of the anisotropic ice fabric on seismic velocities and reflection coefficients, englacially as well as for the ice–bed contact. Hence, it is possible to remotely determine the bulk ice anisotropy.

scholarly journals Influence of rootstock on the quality of sweet cherry fruits in the conditions of the Lower Volga region

2021 ◽  
Vol 845 (1) ◽  
pp. 012063
Author(s):  
OA Nikolskay ◽  
A V Solonkin ◽  
E N Kikteva
Keyword(s):  
Sweet Cherry ◽  
Climatic Conditions ◽  
Lower Volga Region ◽  
One Dimensional ◽  
Qualitative And Quantitative ◽  
Volgograd Region ◽  
Heat And Moisture ◽  
Quantitative Indicators ◽  
Fruit Plantations

Abstract Sweet cherry is a thermophilic and whimsical crop that reacts painfully to unfavorable meteorological conditions, such as frost, drought or high humidity in the air and soil. At the same time, this crop requires a uniform supply of heat and moisture during the growing season. In the climatic conditions of the Volgograd region, stressful situations often arise that can partially or completely reduce the yield of fruit crops, especially those introduced to our region from other regions. To reduce the risk of losing the yield of fruit plantations, including sweet cherry, it is necessary to pay special attention to the choice of the variety, as well as the rootstock on which this variety is grafted. The publication presents the results of studying the influence of rootstocks on the qualitative and quantitative indicators of sweet cherry fruits, such as taste, weight, uniformity, color, and productivity. According to the results of the study in the field (in the garden), varietal-rootstock combinations were identified that have one-dimensional, crack-resistant, large fruits, while maintaining high and stable productivity. According to the results of research, it was found that the rootstock affects not only the strength of growth and the shape of the crown, but also the quality of the fruit. The most dependent of the studied varieties on the type of rootstock is Euphoria, the lowest weight of berries was observed on the rootstock VSL-1. At the same time, this rootstock has a higher percentage of resistance to cracking of the fruit. Based on the conducted research, it can be concluded that with the help of rootstock, it becomes possible to influence the quality indicators of fruits.

scholarly journals Vertical to Horizontal Spectral Ratio (VHSR) Response of Seismic Wave Propagation in a Homogeneous Elastic – Poroelastic Medium Using The Spectral Finite Element Method

2021 ◽  
Vol 11 (1) ◽  
pp. 95
Author(s):  
Sudarmaji Saroji ◽  
Budi Eka Nurcahya ◽  
Nivan Ramadhan Sugiantoro
Keyword(s):  
Finite Element Method ◽  
Elastic Medium ◽  
Seismic Waves ◽  
Low Frequency ◽  
Seismic Wave Propagation ◽  
P Wave ◽  
Poroelastic Medium ◽  
Compressional Waves ◽  
Spectral Finite Element Method ◽  
Spectral Finite Element

<p>Numerical modeling of 2D seismic wave propagation using spectral finite element method to estimate the response of seismic waves passing through the poroelastic medium from a hydrocarbon reservoir has been carried out. A hybrid simple model of the elastic - poroelastic - elastic with a mesoscopic scale element size of about 50cm was created. Seismic waves which was in the form of the ricker function are generated on the first elastic medium, propagated into the poroelastic medium and then transmitted to the second elastic medium. Pororoelastic medium is bearing hydrocarbon fluid in the form of gas, oil or water. Vertical and horizontal component of velocity seismograms are recorded on all mediums. Seismograms which are recorded in the poroelastic and second elastic medium show the existence of slow P compressional waves following fast P compressional waves that do not appear on the seismogram of the first elastic medium. The slow P wave is generated when the fast P wave enters the interface of the elastic - poroelastic boundary, propagated in the poroelastic medium and is transmited to the second elastic medium. The curves of Vertical to horizontal spectrum ratio (VHSR) which are observed from seismograms recorded in the poroelastic and the second elastic medium show that the peak of VHSR values at low frequency correlated with the fluid of poroelastic reservoir. The highest VHSR value at the low frequency which is recorded on the seismogram is above the 2.5 Hz frequency for reservoirs containing gas and oil in the second elastic medium, while for the medium containing water is the highest VHSR value is below the 2.5 Hz frequency.</p>

scholarly journals "STRESS CONDITION OF ROCK MASS AND FAULTING CALCULATION IN THE MINE WORKING"

2019 ◽  
Vol 134 (4) ◽  
pp. 17-22
Author(s):  
Alexandr E. Klykov ◽  
◽  
Efim S. Klykov ◽  
Georgiy V. Shirokolobov ◽  
◽  
...  
Keyword(s):  
Rock Mass ◽  
Mine Working ◽  
Stress Condition

scholarly journals Settlement network of Novi Pazar municipality: Present state and development tendencies

2006 ◽  
Vol 86 (1) ◽  
pp. 151-164 ◽  
Author(s):  
Dragutin Tosic ◽  
Marija Nevenic
Keyword(s):  
Present State ◽  
Transformation Process ◽  
Regional Structure ◽  
Functional Area ◽  
Settlement System ◽  
Functional Level ◽  
Qualitative And Quantitative ◽  
Urban Core ◽  
Community Area ◽  
Quantitative Indicators

In this paper are given adapted morphological, demographical and functional determinants of the Novi Pazar municipality development settlement network on the basis of relevant theoretical and methodological assumptions and qualitative and quantitative indicators. Municipality settlement network is observed as a subsystem in the settlement system of Novi Pazar functional area. Specifically are emphasized interdependency and conditionality of settlement functional transformation process, which caused differentiation of community area into an urban core-Novi Pazar, periurban ring- more or less suburban villages and rural surrounding. Suggested is a model of microdeveloping nucleuses as an instrument for community decentralization. On the ground of spatial and functional level of settlement integration some micro functional - micro regional structure of the municipality territory, has been identified.

scholarly journals THE ROLE OF NATURAL HEALING RESOURCES OF THE COUNTRY'S REGIONS IN IMPROVING THE QUALITY OF SPA SERVICES FOR FAMILIES

2019 ◽  
Vol 29 (3) ◽  
pp. 407-416
Author(s):  
M.S. Oborin
Keyword(s):  
Statistical Analysis ◽  
Qualitative And Quantitative ◽  
Social And Economic Development ◽  
Effective Use ◽  
Natural Healing ◽  
Quantitative Indicators ◽  
Family Recreation ◽  
Perm Region

Features of the organization of family recreation and treatment on the territories possessing natural healing resources and developed sanatorium and resort complex are considered. The research materials are scientific works in the field of assessment of natural and climatic potential of territories, directions of its effective use in social and economic development of regions. The functions of the sanatorium and resort complex are characterized, the data on the state of family and children's recreation and treatment are given on the example of the Perm region. The main methodology of the study is an expert survey and statistical analysis. The qualitative and quantitative indicators of family and children's recreation and treatment are considered, the actual directions of development of sanatorium and resort offer for this group of consumers are revealed. Measures are proposed to optimize the use of natural healing resources of the region in order to improve the quality of family holidays.

scholarly journals Multi-angle and nonuniform ground motions on cable-stayed bridges

2021 ◽  
pp. 875529302110513
Author(s):  
Eleftheria Efthymiou ◽  
Alfredo Camara
Keyword(s):  
Seismic Response ◽  
Ground Motion ◽  
Seismic Waves ◽  
Incidence Angle ◽  
Design Parameters ◽  
System Configuration ◽  
Cable System ◽  
Parametric Problem ◽  
Wide Range ◽  
Cable Stayed Bridges

The definition of the spatial variability of the ground motion (SVGM) is a complex and multi-parametric problem. Its effect on the seismic response of cable-stayed bridges is important, yet not entirely understood to date. This work examines the effect of the SVGM on the seismic response of cable-stayed bridges by means of the time delay of the ground motion at different supports, the loss of coherency of the seismic waves, and the incidence angle of the seismic waves. The focus herein is the effect of the SVGM on cable-stayed bridges with various configurations in terms of their length and of design parameters such as the pylon shape and the pylon–cable system configuration. The aim of this article is to provide general conclusions that are applicable to a wide range of canonical cable-stayed bridges and to contribute to the ongoing effort to interpret and predict the effect of the SVGM in long structures. This work shows that the effect of the SVGM on the seismic response of cable-stayed bridges varies depending on the pylon shape, height, and section dimensions; on the cable-system configuration; and on the response quantity of interest. Furthermore, the earthquake incidence angle defines whether the SVGM is important to the seismic response of the cable-stayed bridges. It is also confirmed that the SVGM excites vibration modes of the bridges that do not contribute to their seismic response when identical support motion is considered.

scholarly journals Theoretical basis for the formation of damaging factors during the coal aerosol explosion

2021 ◽  
Vol 15 (4) ◽  
pp. 130-138
Author(s):  
Olena Zavialova ◽  
Viktor Kostenko ◽  
Natalia Liashok ◽  
Mykola Grygorian ◽  
Tetiana Kostenko ◽  
...  
Keyword(s):  
Mine Working ◽  
Gaseous Medium ◽  
Coal Dust ◽  
Theoretical Research ◽  
Dust Explosion ◽  
Characteristic Points ◽  
Explosion Mechanism ◽  
Mine Workings ◽  
Negative Factors ◽  
Dust Deposits

Purpose. Assessing the process of damaging factors formation during the coal aerosol explosion in mine workings on the basis of theoretical research of the explosion of coal dust deposits in order to substantiate promising methods of protecting miners from their impact. Methods. An integrated approach is used, which includes a critical analysis of literature data on the occurrence and development of coal aerosol explosions in mine workings; theoretical research into the state of the gaseous medium at the characteristic points of the development diagram of the coal dust deposits explosion as a result of mining operations based on the laws of classical physics and chemistry. Findings. The main aspects of the explosion mechanism of dust in a powdery state, accumulated on the surfaces along the mine working perimeter, and the formation of such negative factors as the effect of gaseous medium accelerated movement, have been revealed; high temperature formed during coal and methane detonative combustion; increased gas pressure. The revealed aspects of the dust explosion mechanism make it possible to determine the main directions for protection of miners caught in the explosion. The diagram of the development of settled coal dust explosion along the mine working with normal ventilation conditions, taking into account the influence of seismic waves, has been improved. Originality. Analytical dependences, reflecting the value of gas energy at characteristic points of the diagram, have been determined, and the dynamics of the formation of negative factors caused by the explosion have been revealed. Practical implications. Possible ways of protecting miners from the impact of negative factors caused by the coal aerosol explosion and reducing the severe consequences of such accidents are proposed.

scholarly journals ИССЛЕДОВАНИЕ ВОЗМОЖНОСТИ РЕГИСТРАЦИИ МЕДЛЕННЫХ ДЕФОРМАЦИОННЫХ ВОЛН ЛАЗЕРНЫМ ДЕФОРМОГРАФОМ

2019 ◽  
Author(s):  
I.Y. Rasskazov ◽  
V.A. Lugovoy ◽  
D.I. Tso
Keyword(s):  
Rock Mass ◽  
Experimental Research ◽  
Seismic Waves ◽  
Gulf Of Alaska ◽  
Rock Massif ◽  
Experimental Investigations ◽  
Correct Interpretation ◽  
Acoustic Activity ◽  
Laser Measurements ◽  
Deformation Processes

В статье представлены экспериментальные исследования по обнаружению медленных деформационных волн, интенсифицирующих геомеханические процессы в массиве горных пород, с применением высокочувствительных лазерных измерений. Проведены результаты экспериментальных исследований по оценке влияния удаленных землетрясений на состояние горного массива Стрельцовского рудного поля, регистрации удаленных землетрясений и их предвестников. Приведены результаты регистрации землетрясения в заливе Аляска. Установлено влияние удаленных землетрясений на акустическую активность горного массива, которое проявляется в виде значительного увеличения количества акустических событий и их энергии после регистрации сейсмической волны. Выявлено, что наличие деформационных и сейсмических волн от удаленных землетрясений можно отнести к дополнительным факторам, инициирующим деформационные процессы в горном массиве. Своевременная регистрация данных волн и корректная их интерпретация позволят значительно повысить достоверность прогноза энергетических геодинамических событий в удароопасных массивах горных пород при разработке месторождений в целях предотвращения катастрофических событий.The article presents experimental investigations on the detection of slow waves intensifying geomechanical processes in rock massif, with the application of highsensitivity laser measurements. The results of experimental research for the evaluation of remote earthquakes impact on the condition of rock massif of Streltsovskoe ore field, registration of remote earthquakes and their forerunners are given. The results of the earthquake in the Gulf of Alaska, is represented in the article. The influence of distant earthquakes on the rock mass acoustic activity, which manifests itself in the form of a significant increase in the number of acoustic events and their energy after the registration of a seismic wave, is established. It is revealed that the presence of deformation and seismic waves from distant earthquakes can be attributed to additional factors that initiate deformation processes in the rock massif. Timely recording of these waves and their correct interpretation will significantly improve the accuracy of the prediction of energy geodynamic events in shockhazardous rock masses when developing fields in order to prevent catastrophic events.

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