Results 71 to 80 of about 357,318 (209)
Cartels, managerial incentives, and productive efficiency in German coal mining, 1881-1913 [PDF]
In this paper, we evaluate the impact of cartelisation and managerial incentives on the productive efficiency of German coal mining corporations. We focus on coal mining in the Ruhr district, Germany’s main mining area.
Carsten Burhop, Thorsten Luebbers
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Study on the effect of mining height on overburden strata movement in longwall mining
International Journal of Coal Science & TechnologyThe mining height of a coal seam is a critical factor influencing the detachment, collapse, and formation of the collapse angle of the strata during strata movement. To clarify the mechanism by which mining height affects strata movement characteristics,
Ying Ma +6 more
doaj +1 more source
Research on intelligent conveying technology of 500 m ultra-long face scraper
Meitan kexue jishuIn the field of medium and thick coal seam mining, intelligent mining of ultra-long face is the development trend of coal mining technology, and intelligent transportation is an important part of it.Based on the summary of the problems of the scraper ...
Weixiu CUI +3 more
doaj +1 more source
Have Prices of Internationally Traded Steam Coal been Marginal Cost Based? [PDF]
During 2007 and 2008 steam coal prices soared to unprecedented levels. Since then much has been speculated about the drivers of these price peaks. This paper is concerned with the costs of steam coal allocation in the seaborne market and their influence ...
Paulus, Moritz, Trueby, Johannes
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Optimal selection test of material ratio in the top of Ordovician limestone grouting reconstruction
Meitan kexue jishuIt is an effective method to reduce the risk of floor water inrush by grouting reconstruction and sealing of water channel on top of Ordovician limestone before deep confined water mining in Huabei type coal mine in China. The basic properties of fly-ash
Zhenli FAN +5 more
doaj +1 more source
Sikap Masyarakat Desa Hutan terhadap Perubahan dan Alih Guna Kawasan Hutan Menjadi Kawasan Pertambangan Batubara [PDF]
, 2016 Change and use change forest into coal mining area has led to changes in the biophysical environment and social environment forest villagers. This study aimed to analyze the attitudes towards changes in environmental conditions biophysical and social ...
Hafizianor, H. (Hafizianor)
core +1 more source
Meitan xuebaoThe practice of impact resistance support in dangerous roadways has shown that energy absorbing and buffering components can improve the impact resistance performance of rockbolt support systems. A rubber cushion layer was used as an energy absorbing and
Zhiguo LU +8 more
doaj +1 more source
Frontiers in Earth ScienceIntroductionThis study aims to investigate the fractal characteristics of acoustic emission (AE) signals during coal-rock rupture and their predictive significance for impact dynamic hazards.MethodsTrue triaxial loading/unloading tests were conducted on ...
Fuquan Gao +10 more
doaj +1 more source
Localization of Acoustic Emission Source in Rock Using SMIGWO Algorithm
International Journal of Coal Science & TechnologyThe Grey Wolf Optimization (GWO) algorithm is acknowledged as an effective method for rock acoustic emission localization. However, the conventional GWO algorithm encounters challenges related to solution accuracy and convergence speed.
Jiong Wei +4 more
doaj +1 more source