scholarly journals Hydrodynamic and hydrostatic forces as factors affecting tailing dump stability

2021 ◽  
Vol 44 (1) ◽  
pp. 63-72
Author(s):  
D. Sh. Sharipov

The study of the processes occurring deep in the earth's crust has always been a relevant research topic. The results of these studies allowed development and safe mining of mineral deposits in various conditions. The growth in the consumption of extracted resource and the increase in the scale of mining are forcing enterprises to search for the solutions to complex engineering and technical problems, one of which is the problem of displacement of rock masses and the earth's surface in industrial production-affected areas including tailings dams. The purpose of this study is to improve the operation safety of tailing dams. The object of the study is embankment dams of dressing plant tailing dumps. The subject of the study is deformation processes occurring in dam bodies and slope surfaces. The main research methods used in the work are: the study of safe operation methods for tailing dams based on the operating conditions of Uchalinskoye tailing dump using the modern methods of stability assessment, analysis and generalization of domestic and foreign experience, as well as the study of current methods of geomechanical monitoring of deformation processes – engineering and geological, geophysical, mine surveying and hydrogeological ones. The article describes geographic, hydrographic, climatic, geological and mining operation conditions of the tailing dump of Uchalinsky GOK (Ore Mining and Processing Plant) JSC. The influence of hydrodynamic and hydrostatic forces on embankment tailing dam stability is substantiated. Based on the data obtained and the research methods used, it is concluded that hydrodynamic and hydrostatic forces are fundamental destructive factors affecting dams. The results of these studies can be applied at the design stage of hydraulic structures, since they will supplement theoretical knowledge about the impact of liquid waste on the safety of tailing dams and earth-filled dams, as well as allow detecting deformation processes at their initial development stage and making decisions on their elimination.

Author(s):  
Nikolaj Dobrzinskij ◽  
Algimantas Fedaravicius ◽  
Kestutis Pilkauskas ◽  
Egidijus Slizys

Relevance of the article is based on participation of armed forces in various operations and exercises, where reliability of machinery is one of the most important factors. Transportation of soldiers as well as completion of variety of tasks is ensured by properly functioning technical equipment. Reliability of military vehicles – armoured SISU E13TP Finnish built and HMMWV M1025 USA built were selected as the object of the article. Impact of climatic conditions on reliability of the vehicles exploited in southwestern part of the Atlantic continental forest area is researched by a case study of the vehicles exploitation under conditions of the climate of Lithuania. Reliability of military vehicles depends on a number of factors such as properties of the vehicles and external conditions of their operation. Their systems and mechanisms are influenced by a number of factors that cause different failures. Climatic conditions represent one of the factors of operating load which is directly dependent on the climate zone. Therefore, assessment of the reliability is started with the analysis of climatic factors affecting operating conditions of the vehicles. Relationship between the impact of climatic factors and failure flow of the vehicles is presented and discussed.


2018 ◽  
Vol 7 (4.3) ◽  
pp. 130 ◽  
Author(s):  
Hayder Abed Dhahad ◽  
Wissam Hameed Alawee ◽  
Andrii Marchenko ◽  
Dmytro Klets ◽  
Oleg Akimov

A method for estimating the power characteristics of the car engine in various driving regimes is proposed. It is determined that the volume of the free power (engine power reserve) allows the driver to implement the turning parameters and the time of its completion, which are set by the steering parameters, position and the speed of the steering wheels rotation. The engine power reserve is necessary to provide the required maneuverability indicators. The engine power during maneuvering is spent on overcoming the resistance to movement and on providing the impact controlled by the maneuver. The first component of the engine power can be called connected, and the second one can be called the free one or a controlled component. The received analytical expressions allow carrying out at the design stage a rational choice of capacity of the engine by the condition of maintenance of demanded properties of maneuverability. The developed method for constructing the refined acceleration characteristics of the engine makes it possible to determine the dynamic capabilities of the car, taking into account its design features and operating conditions. 


Author(s):  
Alessandro Corsini ◽  
Alessio Castorrini ◽  
Enrico Morei ◽  
Franco Rispoli ◽  
Fabrizio Sciulli ◽  
...  

The actual strategy in offshore wind energy development is oriented to the progressive increase of the turbine diameter as well as the per unit power. Among many pioneering technological and aerodynamic issues linked to this design trend, the wind velocity at the blade tip region reaches very high values in normal operating conditions (typically between 90 to 110 m/s). In this range of velocity, the rain erosion phenomenon can have a relevant effect on the overall turbine performance in terms of power and energy production (up to 20% loss in case of deeply eroded leading edge). Therefore, as a customary approach erosion related issues are accounted for in the scheduling of the wind turbine maintenance. When offshore, on the other hand, the criticalities inherent to the cost of maintenance and operation monitoring suggest the rain erosion concerns to be tackled at the turbine design stage. In so doing, the use of computational tools to study the erosion phenomenon of wind turbines under severe meteorological conditions could define the base-line approach in the wind turbine blades design and verification. In this work, the authors present a report on numerical prediction of erosion on a 6 MW HAWT (horizontal axis wind turbine). Two different blade geometries of different aerodynamic loading, have been studied in a view to explore their sensitivity to rain erosion. The fully 3D simulations are carried out using an Euler-Lagrangian approach. Flow field simulations are carried out with the open-source code OpenFOAM, based on a finite volume approach, using Multiple Reference Frame methodology. Reynolds Averaged Navier-Stokes equations for incompressible steady flow were solved with a k-ε turbulence. An in-house code (P-Track) is used to compute the rain drops transport and dispersion, adopting the Particle Cloud Tracking approach (PCT), already validated on large industrial turbomachinery. At the impact on blade, erosion is modelled accounting for the main quantities affecting the phenomenon, which are impact velocity and material properties of the target surface. Results provide the regions of the two blades more sensitive to erosion, and the effect of the blade geometry on erosion attitude.


1999 ◽  
Vol 122 (4) ◽  
pp. 611-616 ◽  
Author(s):  
Daniel B. Olsen ◽  
Charles E. Mitchell

Current research shows that the only hazardous air pollutant of significance emitted from large bore natural gas engines is formaldehyde CH2O. A literature review on formaldehyde formation is presented focusing on the interpretation of published test data and its applicability to large bore natural gas engines. The relationship of formaldehyde emissions to that of other pollutants is described. Formaldehyde is seen to have a strong correlation to total hydrocarbon (THC) level in the exhaust. It is observed that the ratio of formaldehyde to THC concentration is roughly 1.0–2.5 percent for a very wide range of large bore engines and operating conditions. The impact of engine operating parameters, load, rpm, spark timing, and equivalence ratio, on formaldehyde emissions is also evaluated. [S0742-4795(00)01004-8]


2017 ◽  
Vol 64 (s1) ◽  
pp. 1-13 ◽  
Author(s):  
Lina Pilelienė ◽  
Viktorija Grigaliūnaitė

Abstract Advertising spokesperson is one of the undeniably important factors affecting advertising effectiveness. However, advertising spokesperson has to have some particular features to be effective. Various previous researches resulted in determination of different features of advertising spokesperson and their effectiveness; i.e. type of a spokesperson (celebrity vs. a regular person); gender and race of a spokesperson; etc. were found to have an impact on the spokesperson’s effectiveness. However, the research on the impact of shooting color temperature on its effectiveness is still scarce. Moreover, an assumption can be made that color temperature might cause a different effect depending on advertising spokesperson’s gender. The aim of this paper is to fill this gap by analyzing the relationship between spokesperson’s gender and advertising color temperature in a framework of advertising effectiveness. Neuromarketing research methods were applied to meet the aim and to determine the guidelines for its usage in advertising.


2017 ◽  
Vol 63 (1) ◽  
pp. 14-26
Author(s):  
Marjeta Zorin Bukovšek ◽  
Borut Bratina ◽  
Polona Tominc

AbstractIn Slovenia, many companies try to avoid bankruptcy with the introduction of a compulsory settlement procedure, but only a handful of companies successfully complete the compulsory settlement in the sense of a final repayment of creditors in accordance with the adopted financial restructuring plan. The article identified the factors affecting the confirmation of a compulsory settlement as well as the factors affecting the final repayment of creditors and, thus, permanently eliminated the causes of insolvency. The factors were divided into internal and external, whereby the impact of factors on a successfully completed compulsory settlement was verified using quantitative and qualitative research methods.


Author(s):  
I. V. Kazmina

The article discusses the need to develop information technology in the context of digital transformation in order to increase the competitiveness of high-tech industries. It is determined that in connection with the rapid development of the digital economy, the adaptation of high-tech enterprises to new operating conditions, as well as increasing their competitiveness, is of particular relevance. The need to stimulate investment and entrepreneurial activity in the high-tech industry has been identified. The digital economy implies the automation of business processes within a high-tech enterprise, as well as in relations with contractors and government agencies through the use of modern information technologies. It is proved that the paramount task of the development of the digital economy in Russia is the implementation in the coming years of training the required number of IT specialists capable of providing a qualitative technological breakthrough. A special role in the digital economy is given to high-tech production. The competitiveness of high-tech enterprises is largely due to the use of modern digital technologies in management and production activities. In conditions of high-tech production, factors affecting the competitiveness of enterprises are unstable. A list of external and internal factors affecting the level of competitiveness of high-tech enterprises is established from the standpoint of the greatest degree of influence of information technologies on them. Ignoring the transition to a digital economy can even deprive a successful high-tech company of its competitive advantage. Creation of new and improvement of existing network information technologies in the digital economy and their implementation in domestic high-tech enterprises will increase the competitiveness of enterprises, and as a result, the country's competitiveness.


2020 ◽  
Vol 5 (1) ◽  
pp. 27-47
Author(s):  
Sitti Aisyah. M Aisyah ◽  
Sappaemi

The Corona virus pandemic exploited by irresponsible elements.  They do a cunning business strategy, which is to hoard goods, in fiqhi terms known as iḥtikār. In the Islamic view, iḥtikār is a prohibited business practice and will be met with a painful punishment in the afterlife.  The purpose of this paper is to provide an understanding about the impact of COVID 19 on the practice of buying and selling (iḥtikār).  This paper uses qualitative research methods in the form of library reseach using the shar'i approach.  From this study it can be concluded that the behavior of hoarding goods with the aim of reselling them at high prices to obtain large profits.  In Islamic Shari'ah, iḥtikār‘s law is haram because it contains elements that harm others.  This is very clearly stated in QS al-Humazah/109: 1-2 and punished by sin as stipulated in the hadith of the Messenger of Allah.


2017 ◽  
Vol 1 (1) ◽  
Author(s):  
La Ode Jabuddin ◽  
Ayub M Padangaran ◽  
Azhar Bafadal Bafadal

This study aims to: (1) Knowing the dynamics of fiscal policy and the performance of the agricultural sector, (2) Analyze the factors that influence fiscal policy and the performance                   of the agricultural sector, and (3) Analyzing the impact of fiscal policy on the performance of the agricultural sector. The data used in this study were pooled 2005-2013 data in the aggregate. Econometric model the impact of fiscal policy on the performance of the agricultural sector is built in the form of simultaneous equations, consisting of 7 equations with 25 total variables in the model, 7 endogenous variables, 12 exogenous variables, and 6 variables lag. The model is estimated by 2SLS method SYSLIN procedures and historical simulation with SIMNLIN procedure.The results showed that: (1) The development of fiscal policy in Southeast Sulawesi from year to year tends to increase, (2) The performance of the agricultural sector from the aspect of GDP has decreased, from the aspect of labor is still consistent, in terms of investment to grow positively, and assign roles which means to decrease the number of poor people, (3) factors affecting fiscal policy is local revenues, equalization funds, other revenues, as well as the lag fiscal policy, (4) the factors that affect the performance of the agricultural sector from the aspect GDP is labor, direct expenditure and GDP lag; from the aspect of labor is the total labor force, investment, land area, direct expenditure, as well as the lag of labor; from the aspect of investment is influenced by GDP per capita, land area, interest rates and investment lag; as well as from the aspect of poor people, are affected by population, investments, direct expenditure and poverty lag, (5). Fiscal policy impact on the agricultural sector GDP increase, a decrease in the number of poor, declining agricultural laborers, and a decrease in the amount of investment in the agricultural sector.Keywords: Fiscal policy, the performance of the agricultural sector, the simultaneous equations


2005 ◽  
Vol 33 (3) ◽  
pp. 156-178 ◽  
Author(s):  
T. J. LaClair ◽  
C. Zarak

Abstract Operating temperature is critical to the endurance life of a tire. Fundamental differences between operations of a tire on a flat surface, as experienced in normal highway use, and on a cylindrical test drum may result in a substantially higher tire temperature in the latter case. Nonetheless, cylindrical road wheels are widely used in the industry for tire endurance testing. This paper discusses the important effects of surface curvature on truck tire endurance testing and highlights the impact that curvature has on tire operating temperature. Temperature measurements made during testing on flat and curved surfaces under a range of load, pressure and speed conditions are presented. New tires and re-treaded tires of the same casing construction were evaluated to determine the effect that the tread rubber and pattern have on operating temperatures on the flat and curved test surfaces. The results of this study are used to suggest conditions on a road wheel that provide highway-equivalent operating conditions for truck tire endurance testing.


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