scholarly journals Conceptual considerations of the modernization of the main fan stations of mine Y and their economic aspect

2021 ◽  
Vol 906 (1) ◽  
pp. 012053
Author(s):  
Piotr Mocek

Abstract In connection with the liquidation of the hard coal mine Y and the change its functionality, it is necessary to modernize the main fan station installed at the “Northern” shaft of mine Y. The article presents concepts of changing the efficiency of WPK 5.0 fans installed in the “Northern” shaft and the methods of air flow regulation for target model of a mine with a reduced network of mining excavations. It discusses four alternative variants of technical solutions. The most effective of them are illustrated with a preliminary economic analysis, the results of which enable the right investment decision to be made.

2010 ◽  
Vol 142 (3) ◽  
pp. 28-40
Author(s):  
Marek BRZEŻAŃSKI ◽  
Edward PIECZORA ◽  
Krzysztof KACZMARCZYK

The examples of application of combustion engines for the mining machinery drive have been presented in the article. The corresponding regulations concerned diesel combustion engines use in mines have been also presented. Moreover, the new technical solutions in such type engines aiming at the use safety increase and the exhaust gas toxic components emission decrease have been proposed.


2021 ◽  
Vol 906 (1) ◽  
pp. 012052
Author(s):  
Piotr Mocek

Abstract The article presents the results of the analysis and calculations of the ventilation network of the decommissioned hard coal mine Y for the model of its target operation. After the end of hard coal mining and the liquidation of most of the mining excavations, the former Y hard coal mine will become an element of the drainage system and a protection for other, still active mining plants. In order for the Y excavation to be transformed into a mine water pumping station, its ventilation system should be rebuilt, and new parameters of the main fan should be determined for a smaller network of mining excavations. For this purpose, using the AERO-2016D program by POK “Zachód” Spółka z o.o., the parameters of the ventilation network were simulated in the target model of mine Y after the liquidation of the “Southern” shaft and mining excavations at levels 530m and 660m. The results of the simulation made it possible to select the optimal main fans for the target model of the transformed mine Y.


2014 ◽  
Vol 59 (4) ◽  
pp. 887-896 ◽  
Author(s):  
Przemysław Skotniczny

Abstract The paper discusses the results of the numerical simulation of a sudden outflow of the air-methane mixture from behind a powered support, for a longwall ventilated by means of the U-type ventilation system. The calculations were performed using the geometrical model of an actual longwall - the I 100 longwall at the „Sośnica” hard coal mine. The steady state of the air flow in the area of the upper corner was discussed, together with the phenomenon of methane seepage from the goaf area in the vicinity of the longwall outlet. Subsequently, the phenomenon of a sudden methane outflow - followed by the ventilation of headings - was introduced into the study. The obtained results confirm the knowledge provided by the mining practice and experience


2020 ◽  
Vol 67 (1) ◽  
pp. 28-34
Author(s):  
Aleksandr V. Vinogradov ◽  
Aleksey V. Bukreev

When repairing and replacing electrical wiring in enterprises, the main difficulty is the lack or poor quality of documentation, plans for conductors laying. Distinguishing wires (cables) and their cores by the color of the shells or using tags attached to the ends is difficult if the shells have the same color and there are no tags. Devices and technical solutions used to identify wires and cables do not allow recognizing conductors without breaking the electrical circuit, removing insulation, and de-energizing the network. Searching for the right conductor is a time-consuming operation. (Research purpose) The research purpose is developing a new microcontroller device for identifying wires using an acoustic signal. (Materials and methods) Literature sources has been searched for devices for conductors identifying. (Results and discussion) The article proposes a method that involves feeding an acoustic signal to a wire at one point and capturing it at another, in order to recognize the desired wire. The article presents results of comparison of the developed microcontroller device for identifying conductors using an acoustic signal with known devices and methods for conductors recognizing. (Conclusions) The article reveals the shortcomings of existing methods and means of identifying wires and cables. Authors performed a theoretical calculation of the sound pressure in the conductor at a given distance. The article presents the calculation of speed of acoustic waves in conductors with different types of insulation. Authors designed a microcontroller device for identifying conductors using an acoustic signal and tested it. It was determined that the device increases the safety of work, reduces the cost of operating internal wiring and identification time; eliminates the violation of wire insulation, the need to disable electrical receivers. The convergence of theoretical calculations and experimental data was shown.


2008 ◽  
Vol 25 (6) ◽  
pp. 315-321 ◽  
Author(s):  
Martin Krüger ◽  
Sabrina Beckmann ◽  
Bert Engelen ◽  
Thomas Thielemann ◽  
Bernhard Cramer ◽  
...  

2021 ◽  
Author(s):  
Yamini Aiyar ◽  
Vincy Davis ◽  
Gokulnath Govindan ◽  
Taanya Kapoor

The study was not designed to undertake an evaluation of the success or failure of reform. Nor was it specifically about the desirability or defects of the policy reform choices. It took these reform choices and the policy context as a given. It is important to note that the Delhi reforms had its share of criticisms (Kumar, 2016; Rampal, 2016). However, our goal was not to comment on whether these were the “right” reforms or have their appropriateness measured in terms of their technical capability. This study sought to understand the pathways through which policy formulations, designed and promoted by committed leaders (the sound and functional head of the flailing state), transmit their ideas and how these are understood, resisted, and adopted on the ground. In essence, this is a study that sought to illuminate the multifaceted challenges of introducing change and transition in low-capacity settings. Its focus was on documenting the process of implementing reforms and the dynamics of resistance, distortion, and acceptance of reform efforts on the ground. The provocative claim that this report makes is that the success and failure, and eventual institutionalisation, of reforms depend fundamentally on how the frontline of the system understands, interprets, and adapts to reform efforts. This, we shall argue, holds the key to upending the status quo of “pilot” burial grounds that characterise many education reform efforts in India. Reforms are never implemented in a vacuum. They inevitably intersect with the belief systems, cultures, values, and norms that shape the education ecosystem. The dynamics of this interaction, the frictions it creates, and reformers’ ability to negotiate these frictions are what ultimately shape outcomes. In the ultimate analysis, we argue that reforming deeply entrenched education systems (and, more broadly, public service delivery systems) is not merely a matter of political will and technical solutions (although both are critical). It is about identifying the points of reform friction in the ecosystem and experimenting with different ways of negotiating these. The narrative presented here does not have any clear answers for what needs to be done right. Instead, it seeks to make visible the intricacies and potential levers of change that tend to be ignored in the rush to “evaluate” reforms and declare success and failure. Moving beyond success to understand the dynamics of change and resistance is the primary contribution of this study.


2021 ◽  
Vol 11 (2) ◽  
pp. 2185-2204
Author(s):  
M. Siraji ◽  
Na zar ◽  
M.S. Ishar Ali

The research aims to examine the influence of irrational behaviour on stock investment decision, specifically, anchoring, disposition effect, home bias, herding, overconfidence and the risk perception. The research further investigates the moderating role of gender between irrational behaviour and stock investment decision. Finally, it reveals which irrational behaviour is most prevalent. A survey collected the primary data from 425 individual investors. The survey evidence shows that, of six irrational behaviours, anchoring, disposition effect, overconfidence and risk perception were influence the investment decision of individual investors, and risk perception comes out to be the significant irrational behaviour on stock investment decision. It further explores that gender has a significant moderation for anchoring, disposition effect, herding, overconfidence, risk perception, and stock investment decision. We recommend that if individuals are aware of the behavioural biases, it will help them for making the right stock investment decisions. The study also relevant for financial advisors, stockbrokers and policymakers as it facilitates them in gaining a better understanding of their clients’ irrational behaviour. The present study gives a unique insight into the individual investors’ profile of gender corresponding to each main irrational behaviour on investment decision under consideration of stock investment.


2014 ◽  
Vol 1029 ◽  
pp. 118-123
Author(s):  
Rodica Bădărău ◽  
Teodor Miloş ◽  
Ilare Bordeaşu ◽  
Adrian Bej

The paper presents a case study on the original solution of a flange shaft as part of the root area of a 5 kW wind turbine blade. There were analyzed the causes that led to the shaft breakage under wind loadings in extreme weather conditions, and consequently technical solutions have been searched in order to improve the shaft design making it more reliable as mechanical strength at extreme wind loadings. The flange shaft is a welded subassembly that keeps the blades attached to the rotor hub. The first part of the paper consists in an analysis referring the loading status, the materials used for blade manufacturing, the identification of critical areas where the breaking was initiated and also the causes for which the materials assumed and specified in the technical design and manufacturing technology failed under loading at wind gusts of about 30 m/sec. Based on this preliminary analysis, the second part of the paper presents the technical solutions which were considered in reference to the materials and the improved design concept aiming to provide the right mechanical strength necessary to withstand specific wind loadings in extreme weather conditions.


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