THE USE OF ACOUSTIC WAVES TO SUPPRESS THE COMBUSTION PROCESS IN THE FIRE SEAT

2021 ◽  
pp. 10-17
Author(s):  
Olena Ivannikova
Keyword(s):  
Acoustic Waves ◽  
Pulse Shape ◽  
Combustion Process ◽  
Acoustic Method ◽  
Acoustic Lens ◽  
Initial Stage ◽  
Power Frequency ◽  
Acoustic Impact ◽  
The Relationship ◽  
Frequency Pulse

Іn this article, the foundations of the formation of the acoustic method of impact on the combustion center have been considered. The relationship between the parameters of the acoustic impact on the source of an emergency arising from a fire, depending on the burning substance has been established. Separate proposals on the parameters of acoustic impact (power, frequency, pulse shape) and design solutions for acoustic systems for suppressing the combustion process in the fire source at the initial stage of the development of an emergency have been developed. Key words: acoustic method, acoustic impact, combustion process, emergency, acoustic lens.

The influence of ultrasound signal parameters on sonoluminescence light intensity

2013 ◽  
Vol 62 (4) ◽  
pp. 605-612
Author(s):  
Marek Szmechta ◽  
Tomasz Boczar ◽  
Dariusz Zmarzły
Keyword(s):  
Acoustic Emission ◽  
Acoustic Waves ◽  
Power Transformer ◽  
Electrical Power ◽  
Partial Discharges ◽  
Research Project ◽  
Insulation Systems ◽  
Secondary Phenomenon ◽  
New Research ◽  
The Relationship

Abstract Topics of this article concern the study of the fundamental nature of the sonoluminescence phenomenon occurring in liquids. At the Institute of Electrical Power Engineering at Opole University of Technology the interest in that phenomenon known as secondary phenomenon of cavitation caused by ultrasound became the genesis of a research project concerning acoustic cavitation in mineral insulation oils in which a number of additional experiments performed in the laboratory aimed to determine the influence of a number of acoustic parameters on the process of the studied phenomenona. The main purpose of scientific research subject undertaken was to determine the relationship between the generation of partial discharges in high-voltage power transformer insulation systems, the issue of gas bubbles in transformer oils and the generated acoustic emission signals. It should be noted that currently in the standard approach, the phenomenon of generation of acoustic waves accompanying the occurrence of partial discharges is generally treated as a secondary phenomenon, but it can also be a source of many other related phenomena. Based on our review of the literature data on those referred subjects taken, it must be noted, that this problem has not been clearly resolved, and the description of the relationship between these phenomena is still an open question. This study doesn’t prove all in line with the objective of the study, but can be an inspiration for new research project in the future in this topic. Solution of this problem could be a step forward in the diagnostics of insulation systems for electrical power devices based on non-invasive acoustic emission method.

INTERACTION BETWEEN A FAMILY DOCTOR AND A DENTIST AT AN EARLY STAGE IN THE PREVENTION OF DISEASES OF THE GASTROINTESTINAL TRACT

2021 ◽  
Vol 2 (12(81)) ◽  
pp. 39-43
Author(s):  
M. Ibragimov ◽  
Y. Heydarova ◽  
A. Alizade ◽  
L. Ibragimova
Keyword(s):  
Gastrointestinal Tract ◽  
Oral Cavity ◽  
Early Stage ◽  
Family Doctor ◽  
Scientific Article ◽  
Oral Manifestations ◽  
Family Doctors ◽  
Long Period ◽  
Initial Stage ◽  
The Relationship

This scientific article discusses the oral manifestations of diseases of the gastrointestinal tract. This problem is relevant both for dentists and family doctors. In medicine, for a long period of time, the relationship between diseases affecting the gastrointestinal tract and their symptoms manifested in the oral cavity has been considered. Many scientists and physicians have dealt with this problem, their several opinions are presented in this article. There is a hypothesis among researchers that the oral cavity is a mirror in which all human diseases can be visible. In the oral cavity, most of the alterations occurring in the organism are manifested, due to which, with an attentive attitude to oral manifestations, the disease can be detected already at the initial stage.

Prospects for Cooperation Between Russia and Syria in Various Scenarios of Military Conflict Development

2021 ◽  
pp. 50-55
Author(s):  
Alheder Haled
Keyword(s):  
Growth Rate ◽  
Inverse Correlation ◽  
Foreign Economic Policy ◽  
Military Conflict ◽  
Political Situation ◽  
Gdp Growth Rate ◽  
Initial Stage ◽  
Military Conflicts ◽  
The Military ◽  
The Relationship

The paper is devoted to determining the prospects for cooperation between Russia and the Syrian Arab Republic in various scenarios of military conflicts. In order to identify the relationship between the success of the country's foreign economic policy and the military conflicts waged on its territory, a study was conducted of such indicators of Syria as: the growth rate of the peace index and the GDP growth rate. A strong inverse correlation is revealed, which means that the level of political situation and peace in the state determines the efficiency of the economy. In view of this, various scenarios of the development of the military conflict in Syria have been studied: at the initial stage, at the stage of active hostilities, at the present stage of overcoming the crisis. The last stage involves four different scenarios for the development of a military conflict, including a local nature and a protracted nature with the involvement of other countries of the world. Options for developing cooperation between Russia and Syria have been identified for each scenario. Taking into account the assessment of the international political situation, the two most likely scenarios for further military events in Syria are identified, and the prospects for cooperation between Russia and Syria in these conditions are outlined.

scholarly journals Innovation and Entrepreneurship in a Space-time Framework Based on the Case of Poland

2019 ◽  
Vol 15 (2) ◽  
pp. 24-39
Author(s):  
Aleksandra Gaweł
Keyword(s):  
Research And Development ◽  
Explanatory Power ◽  
Regression Function ◽  
Regression Analyses ◽  
Initial Stage ◽  
Start Ups ◽  
The Relationship ◽  
Innovation Impact ◽  
Yearly Data ◽  
Innovation And Entrepreneurship

Although innovation and entrepreneurship have been subjects of researchers’ interests for years, nevertheless both the concepts and the relationships between them remain controversial. Since different indices are accepted for the measurement of these categories, the question is whether the relationship between them depends on the choice of measures. The aim of the paper is to indicate the innovation impact on the entrepreneurial process with regard to different measures of these concepts. The research was conducted with the use of regression analyses as a method and yearly data for Polish regions in the period 2003–2018. At the initial stage of the research as many measures of innovation and entrepreneurship as possible were introduced into the estimation of regression function parameters. Statistically insignificant variables were deleted at later stages of research. This research confirms that innovativeness and entrepreneurship are broad concepts and the relationship between them depends on the choice of measures. Saturation with enterprises and saturation with start-ups seem to be more sensitive to innovation than other measures of entrepreneurship. Innovation seen as input, measured by spending on research and development (R&D) has a bigger influence on entrepreneurship than the output innovation measured by revenues from innovative activities. Considering a relatively low level of explanatory power of innovations, it seems they are not the only factor influencing entrepreneurship.

scholarly journals The relationship between the effectiveness of performing technical elements and indicators of static and dynamic balance in young acrobats 6-7 years old

2021 ◽  
Vol 7 (4) ◽  
pp. 58-68
Author(s):  
T. Chernykh ◽  
V. Mulyk ◽  
K. Mulyk ◽  
А. Skaliy ◽  
А. Ostrowski ◽  
...  
Keyword(s):  
Correlation Coefficient ◽  
Dynamic Equilibrium ◽  
Dynamic Balance ◽  
Rank Correlation ◽  
Young Athletes ◽  
Spearman’S Rank Correlation ◽  
Spearman’S Rank Correlation Coefficient ◽  
Initial Stage ◽  
Equilibrium Test ◽  
The Relationship

Purpose: to determine the relationship between the performance of basic elements and indicators of static and dynamic balance in the training process of young acrobats 6-7 years. Material and methods. The study involved 16 young acrobats at the stage of initial training (age 6-7 years). All parents of the participants gave written consent for the participation of children in the study. The study involved testing the technique of performing basic elements of sports acrobatics and assessing the static and dynamic balance of young athletes. The relationship between (swallow, shoulder blade, forward squat, wheel (sideways overturning), bridges) and static and dynamic equilibrium tests was determined. Spearman's rank correlation coefficient method was used as a method of statistical analysis. Results. It is established that the largest relationship between the performance of basic elements and static balance in the basic exercises of young acrobats have: Romberg's test with the elements "Swallow", "Stand on the shoulders", "Bridge"; Biryuk test with elements "Swallow", "Wheel", "Bridge"; balance "Swallow" with elements "Swallow", "Wheel"; static equilibrium test with the elements "Swallow", "Rack on the shoulders", "Rolling forward with a squat", "Wheel". Reliable values ​​of the correlation coefficient were established between the tests of dynamic balance and the basic elements of sports acrobatics in young athletes 6-7 years, namely: "Swallow", "Flip forward with a squat", "Wheel" and "Bridge". The analysis of special tests of static and dynamic balance in mastering the basic elements of acrobatics at the first stage of long-term training makes it possible to use them to determine the level of coordination capabilities of young athletes and further improve the use of acrobatic exercises. Conclusions. A reliable relationship between the performance of basic exercises and indicators of static and dynamic balance in young acrobats at the initial stage of training. It is shown that the level of static and dynamic balance is of great importance for the assimilation and improvement of basic elements of technology by young acrobats 6-7 years. Static and dynamic balance tests can be used to individually build training programs and young acrobats. It is shown that sports acrobatics is a significant means of developing the balance of children 6-7 years.

scholarly journals The establishment of Irkutsk Fire-Technical School of the Ministry of Internal Affairs of USSR: historical-pedagogical retrospective

2020 ◽  
pp. 1-7
Author(s):  
Mikhail Aleksandrovich Vasil'ev
Keyword(s):  
Academic Staff ◽  
Educational Institution ◽  
Technical School ◽  
Staff Members ◽  
Formative Stage ◽  
Initial Stage ◽  
Internal Affairs ◽  
Relationship Of ◽  
The Relationship ◽  
Academic Personnel

The subject of this research is the process of establishment of Irkutsk Fire-Technical School during the 1960’s – 1970’s and its professional-pedagogical transformation in the later period of 1990’s. The article covers in the details the question of historical-pedagogical peculiarities in recruitment of the faculty staff of the school with academic personnel at the initial stage. The author explores the question of professional skills of the temporary and permanent academic staff in realization of training, marching drill and combat activities. In the course of this research the author determines and analyzes the factors that influenced the establishment and development Irkutsk Fire-Technical School of the Ministry of Internal Affairs of USSR during the 1960’s – 1970’; as well as peculiarities of pedagogical activity in the formative stage of the educational institution. The article examines the relationship of the cadets and staff members of the school with the service branches. The presented research is relevant for broad audience, since the establishment and development of departmental institution of system of the Ministry of Internal Affairs of USSR in the territory of Baikalia during the 1960’s became a milestone event for education system of the entire Siberian Region.

From Bulbous Bow to Free-Surface Shock Wave—Trends of 20 Years’ Research on Ship Waves at the Tokyo University Tank

1981 ◽  
Vol 25 (03) ◽  
pp. 147-180
Author(s):  
Takao Inui
Keyword(s):  
Shock Wave ◽  
Free Surface ◽  
Field Measurements ◽  
Wave Pattern ◽  
Ship Waves ◽  
Second Stage ◽  
Initial Stage ◽  
Man And Nature ◽  
Bulbous Bow ◽  
The Relationship

Trends of 20 years' research on ship waves at the Tokyo University Tank since 1960 are briefly sketched. Stress is focused on the importance of dialogues between man and nature. The process of these dialogues is exemplified by some typical cases, including the development of bulbous bows and the finding of free-surface shock waves. Wave-pattern pictures are shown to be indispensable for the initial stage of the di alogues, while wave contours and velocity-field measurements serve well in the second stage. The current wave analysis and wake survey may be the third. The relationship between "wavebreaking" and the "free-surface shock wave" is also discussed.

Acoustic waste water clarification practices

2021 ◽  
pp. 32-37
Author(s):  
S. A. Bakharev
Keyword(s):  
Suspended Solids ◽  
Fine Particles ◽  
Far East ◽  
Water System ◽  
Acoustic Method ◽  
Environmental Safety ◽  
Environmental Indicators ◽  
Asia Pacific ◽  
High Productivity ◽  
Acoustic Impact

The article covers the problems of reagent-free clarification of circulating and waste waters of enterprises with their production sites located in valleys of spawning rivers in the environmentally-sensitive northern territories. It is shown that horizontal sumps, widely used at mining enterprises due to their low construction and operation costs, fail to ensure the production and environmental indicators required in the current conditions. The article analyses the results of 20 years of application in the Russian Federation and the countries of the Asia-Pacific region of the complex acoustic method (CAM), based on the mechanisms of coagulation of fine particles, forced sedimentation of initial and coagulated particles, as well as sludge thickening and dewatering. The advantages and limitations are shown for the CAM method, developed by the author of the article and based on the principles of: complexity, with the use of the laws of linear and nonlinear acoustics; acoustic impact on the water system for the purpose of acoustic degassing of water; acoustic coagulation of fine suspended solids (and subsequent gravity sedimentation of the newly formed aggregates); acoustic (forced) sedimentation of the original and previously acoustically coagulated suspended solids; acoustic thickening of sludge in sumps and acoustic dewater ing of sludge at depositing sites with drainage systems; the cascade (boundary) nature of acoustic impacts on the water system in the main water catchers, sumps, etc. The specific behavior of processes under a complex acoustic impact ensures their high productivity and low power consumption values (unattainable by any other methods) and the required environmental safety in the special conditions of the Far North and the Far East.

Indigenous business success: a hybrid perspective

2019 ◽  
Vol 13 (1/2) ◽  
pp. 24-41
Author(s):  
Ruth Omonigho Mrabure
Keyword(s):  
Cultural Context ◽  
Business Success ◽  
Sources Of Information ◽  
Content Type ◽  
Initial Stage ◽  
Indigenous Group ◽  
The Social ◽  
Indigenous Entrepreneurs ◽  
The Relationship ◽  
Subjective Meanings

PurposeThis paper aims to address the notion that the relationship between being indigenous and business success is inconclusive because there are tensions between indigenous values and business success. The research questions are: How do indigenous entrepreneurs define success? Does the third space create a different meaning of success in the indigenous context?Design/methodology/approachA qualitative approach was adopted for this study because the ability to define success requires subjective meanings. Participants’ lived experiences and stories were the main sources of information. Open conversational-style interviews were used because they allow participants to freely share their stories.FindingsA defining line is that not all indigenous entrepreneurs have the same view of success. The homogeneity that emanates from sharing indigeneity does not equal unity in views, but shows that people from the same group can view success differently. However, the meaning and views formed are also connected to the wider community, relationships and predominant values that characterise the social cultural context of the entrepreneur.Research limitations/implicationsThis study focuses on one indigenous group; more studies need to be conducted to gain wider variation on the meaning of success in indigenous entrepreneurship and how indigenous subculture alters these meanings.Practical implicationsThe findings of this study show that success for indigenous entrepreneurs should be defined based on individual philosophy. Hence, practitioners should endeavour to clarify what success means from the initial stage of the business to avoid misconception and make this clear to others that are connected to the business.Originality/valueThis paper suggests a different view of success in an indigenous context using the hybridity viewpoint to explain why success can be perceived using the in-between space without opposite binary.

scholarly journals Mechanical Model of the Initial Leg Pressure Increment of the Shield and Its Application to Monitor Roof Load in Longwall Panels

2020 ◽  
Vol 2020 ◽  
pp. 1-9
Author(s):  
Like Wei
Keyword(s):  
Coal Mine ◽  
Pressure Difference ◽  
Mechanical Model ◽  
Main Roof ◽  
Mine Pressure ◽  
Initial Stage ◽  
Proposed Model ◽  
Pressure Increment ◽  
The Relationship ◽  
Leg Pressure

The shield pressure cannot always be used to represent the upper load of longwall panels, since its value is steady or even decreases by the yielding action. However, the leg pressure increment of the shield (LPIS) at the initial stage is not influenced by yielding and could therefore be an important factor to judge the state of overlying loads. In this study, a mechanical model is established to analyze the relationship between the overlying loads of the main roof and LPIS after cutting. There is a linear positive correlation between leg pressure increment and overlying loads and a second-order relationship between leg pressure increment and length of main roof cantilever in the proposed model. Therefore, it can be used to determine the magnitude of roof weighting strength in different periods as well as the length of the main roof cantilever in a period. Finally, the mine pressure difference between the period of fully mechanized mining and the period of fully mechanized caving mining in the MinDong-1 coal mine serves to verify the rationality of the proposed model.

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