scholarly journals Basic calculation methods of investigation of circumstances and mechanism of man-made explosions

2021 ◽  
Vol 23 (1) ◽  
pp. 258-269
Author(s):  
R. Huseinov ◽  
Yu. Panchuk
Keyword(s):  
Operating Mode ◽  
Research Process ◽  
Poor Quality ◽  
Excess Pressure ◽  
Technological Equipment ◽  
Building Structures ◽  
Calculation Methods ◽  
Explosion Products ◽  
Quality Maintenance ◽  
Equipment And Pipelines

The article purpose is to analyze the danger of man-made explosions and provide calculation methods for determining the mechanism of the occurrence of an explosion during forensic examinations of the study of the circumstances and mechanism of man-made explosions. The relevance of the article is caused by the fact that present-day production and everyday life cannot dispense with the usage of combustible and explosive substances. The particular attention to be paid to emergency prevention related to explosives, as well as the research to determine the mechanism of man-made explosions. The research on the mechanism of man-made explosions will make it possible to determine the technical cause of their occurrence, to analyze for what reason and for whose fault the event occurred, and also what measures should be taken to minimize the likelihood of such situations occurence. It is noted that in order to obtain reliable conclusions about the mechanism of man-made explosions, it is necessary to use scientifically based methods and methodologies allowing us to assess the extent of destruction. The degree of destruction of surrounding building structures and harm to people depends on overpressure caused as the result of a significant expansion of the explosion products and their spread to all directions from the center of explosion. The most frequent causes of explosions in the explosive object are: destruction and damage to production tanks, equipment and pipelines; deviation from production regulations (excess pressure and temperature of equipment operating mode), low-quality control of equipment and work while conducting require work, and untimely or poor-quality maintenance of technological equipment. The main calculation methods for the research of the man-made explosions in open areas, indoors, and limited space are given, which will allow to systematize the research process and analyze the flow of explosions in specific situations, and to establish a mechanism for their occurrence when conducting forensic examinations of the circumstances and mechanism of man-made explosions.

Experimental method of evaluation of performance easily disposable construction

2020 ◽  
pp. 127-137
Author(s):  
V.V. Nizhnyk ◽  
◽  
O.F. Nikulin ◽  
S.V. Pozdeev ◽  
D.O. Dobriak ◽  
...  
Keyword(s):  
Experimental Evaluation ◽  
Building Materials ◽  
Excess Pressure ◽  
Design Parameters ◽  
Building Structures ◽  
Confined Space ◽  
Technical Parameters ◽  
Experimental Stand ◽  
Working Volume ◽  
Method Of Evaluation

This article presents the current state of affairs in cases of explosions in Ukraine and preventive measures to protect against them. The relevance of studies on the substantiation of the methodology for calculating the parameters of easily disposable structures for explosive and fire hazardous premises has been determined. The analysis of domestic and foreign regulatory documents for the design and installation of window openings in buildings for various purposes is carried out. The permissible values of the overpressure of the explosion, which does not cause significant damage to building structures and is safe for people, are considered. The subject of the study is the effect of the amount of gas on the design parameters of the research stand for the experimental evaluation of easily disposable structures. The purpose of this work is to substantiate the design and the main technical parameters of the research stand for assessing the performance of easily sisposable structures. The essence of the proposed research method is to create an excess pressure from the explosion of a mixture of propane-butane with air in the working volume and to study the effect of this excess pressure of the explosion on a prototype of an easily disposable structure. An experimental stand for studying the processes of the influence of the magnitude of the overpressure of an explosion in a confined space on the design parameters of easily disposable structures is simple in design, provides an imitation of a part of a building (structure) fragment and makes it possible to study the possibility of using certain building materials with different geometric parameters as easily disposable structures, which, in turn, allows the researcher to obtain more reliable data for analysis. The existing experimental methods for evaluating the parameters of easily disposable structures are analyzed. The dimensions of the research stand and the parameters of its enclosing structures, the critical values of the overpressure of the explosion, which the stand should create, and the minimum amount of gas, the combustion of which will provide the necessary overpressure of the explosion in the stand, are substantiated. A fundamentally new stand for the experimental evaluation of the parameters of easily disposable structures, a program and experimental research methodology have been developed.

Risk analysis when using structural materials of technological equipment of automobile and gas filling stations

2021 ◽  
Keyword(s):  
Factor Analysis ◽  
Risk Analysis ◽  
Electrochemical Corrosion ◽  
Structural Materials ◽  
Technological Equipment ◽  
Gas Stations ◽  
Quantitative Calculation ◽  
Equipment And Pipelines

The article considers methods of testing technological equipment operating in the conditions of fuel stations, in order to reduce the risks in the production of structural materials for technological equipment of fuel stations, by analyzing the causes of corrosion of pipelines and pipelines, as well as analyzing the risks of increasing the speed of corrosion processes near technological joints and welds. The method of quantitative calculation of risks and methods of testing materials of underground parts of pipelines, taking into account the occurrence of electrochemical corrosion of equipment and pipelines of gas stations and gas stations, the feasibility of using anodic coatings, in order to reduce the risk of destruction of pipe connections that are resistant to corrosion. Keywords corrosion of pipelines; fuel station; factor analysis of risks; corrosion of stray currents; anode coating; fiberglass

Discussion on Calculation Methods of Damping Ratio of the Tower Equipment

2013 ◽  
Vol 694-697 ◽  
pp. 379-382
Author(s):  
Zhen Ya Duan ◽  
Rong Li
Keyword(s):  
Strong Influence ◽  
Damping Ratio ◽  
Real Data ◽  
Research Process ◽  
Structural Behavior ◽  
Design Stage ◽  
Calculation Methods ◽  
Modal Damping ◽  
Tower Equipment ◽  
Semi Empirical

Modal damping ratios are very difficult to predict at the design stage, but have a strong influence on the dynamic structural behavior. This paper describes the research process of damping ratio of the tower equipment. First of all, calculation methods of damping ratio of the tower equipment complying with different standards have been analyzed. Then, the damping ratio of process tower equipments has been calculated by using different calculation methods compared to its real data. The results show that it does not accurately predict the damping ratio of the large tower equipment using existing calculation methods. As a result, the theoretical or semi-empirical formula must be put forward to calculate the damping ratio of the industrial tower.

scholarly journals Hydraulic transport in small livestock farms

2021 ◽  
Vol 274 ◽  
pp. 03003
Author(s):  
Оktyabr Rakhimov ◽  
Laylo Аshurova ◽  
Fotima Artikbekova
Keyword(s):  
Experimental Research ◽  
Operating Mode ◽  
Excess Pressure ◽  
Hydraulic Transport ◽  
Pipeline Transport ◽  
Screw Feeder ◽  
Liquid Feed ◽  
Pig Farms ◽  
Rotary Pumps ◽  
Small Livestock

The article highlights the advantages and benefits of pipeline transport of liquid feed mixtures on small pig farms, the device and the principle of operation and technical characteristics of the improved rotor pump developed by the authors of the article. Methods of experimental research to determine the concentration of feed mixtures, the influence of the shape of the separator on the performance characteristics, the required power and the flow of an improved pump are presented. The results of the experiments showed that one of the bottlenecks limiting the operation of rotary pumps on feed mixtures of increased concentration is the low suction capacity of the pump, that is, the design of the suction pipe of the pump, where an increase in resistance with an increase in the concentration of feed mixtures causes a breakdown of the operating mode and cavitation. To resolve this issue, we used a screw feeder installed in front of the pump suction nozzles. It was found that if the screw feeder provides excess pressure within (about, 0.25 ... 0.3) 105 Pa per suction cavity, the pump operates stably and reliably.

scholarly journals Plant for cleaning oils from oxidation products

2021 ◽  
Vol 264 ◽  
pp. 04043
Author(s):  
Nargiza Kholikova ◽  
Bakhodir Khakimov ◽  
Saydilla Alikulov ◽  
Nargiza Ravshanova ◽  
Ajargul Mambetsheripova
Keyword(s):  
Operating Mode ◽  
Research Process ◽  
Oxidation Products ◽  
Oil Composition ◽  
Cleaning Efficiency ◽  
Friction Process ◽  
Engine Oils ◽  
Agricultural Work ◽  
Oil Purification ◽  
Motor Oils

The study aims to substantiate the parameters and operating mode of the oil purification device from oxidation products to improve the efficiency of the use of lubricants. The methods of mathematical analysis and mathematical statistics, comparative comparison, generalization, and testing methods of agricultural machinery are used in the research process. It is established that engine oils are intensively polluted by oxidation products during processing, thereby accelerating the friction process due to the overload of tractor engines. During the performance of agricultural work in the oil composition, the content of oxidation products in the form of carbon, carbon dioxide, and asphalt products increases by 1.2%. Analytical coupling dependences for the process of cleaning motor oils from oxidizing products are obtained, and the dependence of the cleaning efficiency on the device parameters is established. The developed device consists of a container for collecting oils, a steam generator, a container for a sump mixer, a separate container for pure and sedimentary oils, and a vessel for re-collecting acetone. An installation has been developed to implement the technology of collecting and renewing oils in the conditions of the farm. In this case, the amount of contamination and the composition of oils is determined, and the operating mode of the device is selected for their resumption.

scholarly journals Mobility of aggregates of promising missile systems based on road trains with an active trailed link

2020 ◽  
Vol 1 (3) ◽  
pp. 23-28
Author(s):  
A.A. Berdnikov ◽  
◽  
R.V. Strel'tsov ◽  
V.A. Dyunov ◽  
I.V. Zol'nikov ◽  
...  
Keyword(s):  
Nuclear Explosion ◽  
Excess Pressure ◽  
Steering Wheel ◽  
Technological Equipment ◽  
Supporting Surface ◽  
Average Speed ◽  
The Road ◽  
Wheel Drive ◽  
Turning Center ◽  
Design Factors

The aggregates of advanced missile systems (AAMS) include autonomous launchers of a mobile ground missile complex, transport-and-installation, refueling, maintenance and auxiliary technical means of technological equipment, which must have operational, tactical and strategic mobility. Operationaland tactical mobility is understood as the ability of the AAMS to move from one point to another in a certain time. Strategic mobility is characterized by the adaptability of the AAMS to its loading and transporting by other types of transport, including rail, air, water. The average speed of movement is taken as a measure of mobility, which should be developed by AAMS in order to ensure the timeliness, efficiency and safety of performing the assigned tasks, as well as the possibil-ity of getting out of the influence of the damaging factors of a nuclear explosion, primarily from excess pressure in the front of the shock blast wave. It is possible to increase the mobility of the AAMS by locating it on the basis of road trains, however, the existing designs of aggregates of road trains have disadvantages that reduce the flotation and, as a result, the average speed of movement, these include low support and geometric flotation. The geometric flotation is influenced by design factors. For example, an increase in overall width is typical for a road train, as the trailing link under the influence of lateral reactions of the supporting surface relative to the tractor track is shifted towards the instantaneous turning center. This displacement causes an increase in resistance to movement on deformable soils, and, consequently, a deterioration in flotation and a decrease in a number of other operational properties of the road train. It is possible to increase the mobility of the AAMS by placing them on the basis of a road train with an active trailed link, controlling the distri-bution of power flows supplied to the wheels of an all-wheel drive road train depending on the pos-sibility of realizing free traction by each wheel, changing the position of the road train center of in-flexions depending on the steering wheel angle and maneuver.

scholarly journals Failure and Collapse of Building Structures in the Cities of Yaoundé and Douala, Cameroon from 2010 to 2014

2015 ◽  
Vol 10 (1) ◽  
pp. 23 ◽  
Author(s):  
Jean Claude Tchamba ◽  
Théodore Gautier L. J. Bikoko
Keyword(s):  
Environmental Factors ◽  
Case Studies ◽  
Structural Design ◽  
General Public ◽  
Poor Quality ◽  
Building Industry ◽  
Building Structures ◽  
Building Collapse ◽  
Regulatory Bodies ◽  
Industry Professional

<p class="zhengwen"><span lang="EN-GB">The failure and collapse of buildings in most cases result in loss of lives and properties. The incessant <a name="_GoBack"></a>collapses of buildings nowadays are so enormous that it has become a serious concern to the professionals in the building industry, clients, governments, and general public. In most cases, the architects and engineers who are directly involved in the construction of such building are held responsible for building collapse. The purpose of this study was to elaborate various cases of building structures collapsed that occurred in Yaoundé and Douala, Cameroon between 2010 and 2014 and to investigate the factors causing such incidents. The methods employed in the collection of data include the administration of questionnaire to professionals in the building industry (professional engineers, architects and construction professionals), site inspections and case studies for the sites. The data collected were analysed using descriptive and analytical statistics. The findings show that the collapse of some buildings in major cities in Cameroon (Yaoundé and Douala) can be attributed to absence of soil investigation and foundation, structural design, detailing, degradation due to environmental factors, use of poor quality materials and concrete processing. In the two case studies considered, the study revealed that the major causes of building failures were excessive loading, structural design, degradation due to environmental factors and other causes. The paper concludes by recommending possible measures to be undertaken by government and other regulatory bodies in the building industry to avert this.</span></p>

Analysis of Predictive Calculation Methods of Airborne Sound Insulation

2016 ◽  
Vol 835 ◽  
pp. 573-578 ◽  
Author(s):  
Naďa Zdražilová ◽  
Denisa Donová ◽  
Iveta Skotnicova
Keyword(s):  
Acoustic Properties ◽  
Sound Insulation ◽  
Building Structures ◽  
Calculation Methods ◽  
Airborne Sound ◽  
Mutual Comparison ◽  
Sound Reduction ◽  
Reduction Index

Acoustic properties of building structures are currently very actual theme with regard to the development of new building and insulating materials, while the methods for estimating the airborne sound reduction index evolve mainly from the second half of the 20th century. For mutual comparison of selected prediction methods and for determination of their suitability it has been provided a calculation of weighted sound reduction index RW [dB] from the input parameters of materials identified by laboratory measurements, calculation of weighted apparent sound reduction index R ́W [dB] and these values were compared with in-situ measurements. The aim of this paper is to determine the most appropriate method to calculate RW [dB] and R ́W [dB] values of lightweight building constructions with regard to their practical applicability, accuracy of estimation and complexity of the calculations.

Pervasive Undisclosed Conflicts of Interest in Applied Behavior Analysis Autism Literature

2021 ◽  
Author(s):  
Kristen Bottema-Beutel ◽  
Shannon Crowley
Keyword(s):  
Behavior Analysis ◽  
Applied Behavior Analysis ◽  
Clinical Training ◽  
Conflicts Of Interest ◽  
Research Process ◽  
Poor Quality ◽  
Autism Research ◽  
Positive Effects ◽  
One Year ◽  
Autism Interventions

Objective: Conflicts of interest (COIs) can introduce bias into the research process, and allow researchers to demonstrate positive effects for interventions that are not actually effective. However, there are no studies to date that examine the prevalence of COIs in applied behavior analysis (ABA) autism research. Because ABA services are routinely provided to autistic children as a means to address difficulties associated with autism, this is an important area of investigation. The purpose of this paper is to analyze the extent to which ABA autism interventions published in journals devoted to ABA have clinical/training consultancy COIs.Method: We tallied author COIs in articles published over a one-year period that tested, commented on, or reviewed ABA autism intervention strategies, extracted from eight journals devoted to publishing behavioral research. We focused on COIs related to researcher employment as an ABA clinical provider or a training consultant to ABA clinical providers. Results: We found that 84% of studies had at least one author with this type of COI, but they were only disclosed as COIs in 2% of studies. Additionally, 87% of studies with statements claiming the authors did not have COIs, were authored by researchers found to have clinical/training consultancy COIs. Conclusions: Pervasive, undisclosed COIs likely lead to researcher bias, and could at least partially account for persistent poor quality research in this area. Practitioners should be aware of the prevalence of undisclosed COIs in this literature, and take this into account when providing or recommending ABA services.

Specific Knowledge in Assessment of Local Fire for Design of Building Structures

2014 ◽  
Vol 1001 ◽  
pp. 362-367 ◽  
Author(s):  
Jiří Pokorný ◽  
Petr Kučera ◽  
Vladimír Vlček
Keyword(s):  
Thermal Load ◽  
Building Structures ◽  
Fire Tests ◽  
Calculation Methods ◽  
Specific Knowledge ◽  
Steel Building ◽  
Standard Values

The development of designing building structures exposed to fire is solved not only on the basis of data obtained by standardized tabular values from the fire tests, but also by calculations or their combination with standard values. Calculation methods are becoming more important for most types of building structures, especially for timber and steel building structures. One possibility how to define thermal load of building structures, which is usable especially immediately after the development of a fire, is local fire method. This paper summarizes the principles of calculation while using local fire, it evaluates its positive and negative characteristics, and especially its practical applicability.

Sign in / Sign up

Export Citation Format

Share Document