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Prevention And Control Technology Of Goaf Water Hazard In Unauthorized Mining Areas Of Extremely Soft And Medium-Thick Coal Seams, LI Zhi, ZHENG Shitian, SHI Zhiyuan, WANG Yuhang 2021 China Coal Research Institute, Beijing 100013, China; Xi'an Research Institute Co. Ltd., China Coal Technology and Engineering Group Corp., Xi'an 710077, China; Shaanxi Key Laboratory of Prevention and Control Technology for Coal Mine Water Hazard, Xi'an 710077, China

Prevention And Control Technology Of Goaf Water Hazard In Unauthorized Mining Areas Of Extremely Soft And Medium-Thick Coal Seams, Li Zhi, Zheng Shitian, Shi Zhiyuan, Wang Yuhang

Coal Geology & Exploration

Unauthorized mining in coal pit is common in China's coal industry. As the scope of unauthorized mining and the amount of accumulated water are hard to determine, the goaf water seriously threatens the safety of mining in adjacent large coal mines. In order to explore the unauthorized boundary of coalpits quickly and accurately and prevent the threat of goaf water, the long distance drilling technology of ground bedding borehole in medium and thick coal seam is proposed based on the controllable trajectory and accurate positioning of ground directional drilling, which mainly includes precise drilling in extremely soft and medium-thick coal …


Prediction Model Of Water Inrush From Coal Floor Based On Ga-Bp Neural Network Optimized By Ssa And Its Application, YIN Huiyong, ZHOU Xinlong, LANG Ning, ZHANG Lifeng, WANG Mingli, WU Tao, LI Xin 2021 College of Earth Science and Engineering, Shandong University of Science and Technology, Qingdao 266590, China

Prediction Model Of Water Inrush From Coal Floor Based On Ga-Bp Neural Network Optimized By Ssa And Its Application, Yin Huiyong, Zhou Xinlong, Lang Ning, Zhang Lifeng, Wang Mingli, Wu Tao, Li Xin

Coal Geology & Exploration

With the increase of coal mining depth, coal production process is faced with complex water inrush mechanism and variable water inrush main control factors, and the uncertainties among the factors make the prediction of floor water inrush more difficult. In order to accurately predict the risk of floor water inrush, aiming at the small sample and non-linear problem of floor water inrush, firstly, genetic Algorithm is used to optimize the initial weights and thresholds of network random assignment, and then Sparrow Search Algorithm with strong search ability and good stability is selected to optimize the weights and thresholds for the …


Application Of Unmanned Aerial Vehicle In Surface Soil Characterization And Geological Disaster Monitoring In Mining Areas, LONG Linli, LIU Ying, ZHANG Xuyang, SU Yongdong, CHEN Xiaoyang 2021 School of Earth and Environment, Anhui University of Science and Technology, Huainan 232001, China

Application Of Unmanned Aerial Vehicle In Surface Soil Characterization And Geological Disaster Monitoring In Mining Areas, Long Linli, Liu Ying, Zhang Xuyang, Su Yongdong, Chen Xiaoyang

Coal Geology & Exploration

With the emergence and development of UAVs and the improvement of the miniaturization and intelligence of various sensor, UAVs equipped with sensors have become an efficient tool for obtaining spatial data. Because UAVs are low cost, short revisit period, fast and efficient, light and flexible, simple operation, and high temporal and spatial accuracy of image acquisition, it is widely used in mining land damage monitoring. Using "UAV, Inversion, Soil Monitoring, Surface Collapse, Ground Fissure" as keywords, this paper summarizes the academic papers of the search system in the web of science, CNKI, and Google Scholar from January 2010 to May …


The Development Law Of Surface Cracks In Shallow Coal Seam Mining Through Double Gullies Terrain, SUN Xueyang, ZHANG Huixuan, LU Mingjiao, LI Cheng, MIAO Lintian 2021 School of Geology and Environment, Xi'an University of Science and Technology, Xi'an 710054, China; Key Laboratory of Mine Geological Hazards Mechanism and Control, Xi'an 710054, China; Key Laboratory of Coal Resources Exploration and Comprehensive Utilization, Xi'an 710054, China

The Development Law Of Surface Cracks In Shallow Coal Seam Mining Through Double Gullies Terrain, Sun Xueyang, Zhang Huixuan, Lu Mingjiao, Li Cheng, Miao Lintian

Coal Geology & Exploration

In order to protect the ecological environment of the mining area in the Yellow River Basin, the mining-induced surface crack development law was summarized from the parameters of surface crack development location and development morphology during mining of the working face passing through the double gullies terrain by using a combination of numerical simulation experiments, similar material simulation experiments and theoretical analysis in the context of the working face 125203 of Anshan Coal Mine in Miaohagu Mining Area of Fugu County. Through theoretical analysis, the relative position function T of surface cracks in shallow coal seam mining through double gullies …


Numerical Analysis Of The Effect Of Different Soil Types And Water Content On Heat Transfer Performance Of Horizontal Buried Pipes, ZOU Hang, PEI Peng, HAO Dingyi, WANG Chen 2021 College of Mining, Guizhou University, Guiyang 550025, China

Numerical Analysis Of The Effect Of Different Soil Types And Water Content On Heat Transfer Performance Of Horizontal Buried Pipes, Zou Hang, Pei Peng, Hao Dingyi, Wang Chen

Coal Geology & Exploration

In order to reveal the heat transfer performance of the horizontal buried pipe heat exchanger in the ground source heat pump system in different soil types, this paper, based on the theoretical knowledge of soil capillary water, combined with the means of numerical simulation, discusses the influence of the difference of three-phase composition in different types of energy storage soil on the heat transfer characteristics of the horizontal buried pipe heat exchanger. The results show that under the cooling condition of 308.15 K, the outlet water temperature of the horizontal pipe in the loam soil decreases to 303.3 K and …


Research On The Coal Thickness Prediction Method Based On Vmd And Svm, ZENG Aiping, ZHANG Jiawei, REN Enming, LIU Tao, JIANG Fei, LIU Xingjin, SU Huairui 2021 Engineering Laboratory for Deep Mine Rockburst Disaster Assessment, Jinan 250104, China; Geophysical Prospecting and Surveying Team of Shandong Bureau of Coal Geology, Jinan 250104, China

Research On The Coal Thickness Prediction Method Based On Vmd And Svm, Zeng Aiping, Zhang Jiawei, Ren Enming, Liu Tao, Jiang Fei, Liu Xingjin, Su Huairui

Coal Geology & Exploration

Changes in coal thickness have an important impact on safe and efficient coal mining. In order to solve the problem of large errors in coal thickness prediction results when the 3D seismic data contains noise, a method in which variable modal decomposition(VMD) and support vector machine(SVM) methods are combined for coal thickness prediction is proposed. Firstly, a coal-thickness wedge model is constructed and seismic forward modeling is performed on it. Based on the condition of thin coal seam thickness, the amplitude attribute and bandwidth attribute have a good positive correlation with the coal thickness, while the instantaneous frequency attribute has …


Research And Application Of The Prediction Method For Cbm Enrichment Area Of Low Rank Coal, LUO Zhongqin, LIU Peng, MENG Fanbin Research Institute of Coal Geophysical Exploration, China National Administration of Coal Geology, Zhuozhou 072750, China 2021 Research Institute of Coal Geophysical Exploration, China National Administration of Coal Geology, Zhuozhou 072750, China

Research And Application Of The Prediction Method For Cbm Enrichment Area Of Low Rank Coal, Luo Zhongqin, Liu Peng, Meng Fanbin Research Institute Of Coal Geophysical Exploration, China National Administration Of Coal Geology, Zhuozhou 072750, China

Coal Geology & Exploration

The exploration of low rank coal coalbed methane(CBM) faces the problems of low resource exploration rate and low single well production. And medium and low rank coal CBM exploration is still in the primary stage. In order to improve the predition accuracy of the low rank coal CBM enrichment area, the laboratory test data of 652 coal samples from 56 wells in Hancheng, Jincheng Baode, Ji'ergalangtu Qinshui Basin, Huainan, Huaibei and other places were collected to compare the relationship between gas content and elastic parameters of high, medium and low rank coal samples. The results indicated that the correlation between …


Factors Affecting The Attitude Accuracy Of Wireless Electromagnetic Wave Mwd System, WANG Xiaobo 2021 Xi'an Research Institute Co. Ltd., China Coal Technology and Engineering Group Corp., Xi'an 710077, China

Factors Affecting The Attitude Accuracy Of Wireless Electromagnetic Wave Mwd System, Wang Xiaobo

Coal Geology & Exploration

In broken soft coal seams of coal mine where hydraulic driving directional drilling is used, hole collapse and hole wall instability are easy to occur. Electromagnetic wave measurement while drilling system is suitable for gas driving drilling, so it is widely used in broken soft coal seams. The accuracy of drilling trajectory is the key to gas drainage effect in broken soft coal seams. In the use of electromagnetic wave measurement while drilling system, the phenomenon of insufficient accuracy and large error of trajectory measurement appears irregularly. In order to solve this problem, this paper analyzes all the factors that …


Prediction Of Fracture Distribution And Evaluation Of Shale Gas Preservation Conditions In Longmaxi Formation In Dongxi Area, XIE Jiatong, FU Xiaoping, QIN Qirong, LI Hu 2021 Sinopec Exploration Company, Chengdu 610041, China

Prediction Of Fracture Distribution And Evaluation Of Shale Gas Preservation Conditions In Longmaxi Formation In Dongxi Area, Xie Jiatong, Fu Xiaoping, Qin Qirong, Li Hu

Coal Geology & Exploration

Commercial development of shale gas confirmed that mature shale has great potential for exploration, southeast Sichuan is the strategic pilot area of shale gas exploration and development in southern China, cracks are the key factor of shale gas preservation and development deployment, for the structural environment complex and special basin edge area, increasing the difficulty of shale crack research, but also provides a new direction for shale gas exploration and development. As a new field of oil and gas exploration in China, shale gas exploration has not yet developed a mature crack evaluation system. Taking Dongxi area of the southeast …


A 3d Seismic Physical Modeling System Of Large Double Triaxial Air-Supported Positioning And Multichannel Data Acquisition And Its Application, SHI Xianxin, LIU Qiang, HU Jiwu, WANG Pan, LIAN Chenguang, JIA Qian, ZHANG Miaomiao, NIE Ailan 2021 Xi'an Research Institute Co. Ltd., China Coal Technology and Engineering Group Corp., Xi'an 710077, China

A 3d Seismic Physical Modeling System Of Large Double Triaxial Air-Supported Positioning And Multichannel Data Acquisition And Its Application, Shi Xianxin, Liu Qiang, Hu Jiwu, Wang Pan, Lian Chenguang, Jia Qian, Zhang Miaomiao, Nie Ailan

Coal Geology & Exploration

As an important technology to study seismic wave propagation characteristics, 3D seismic physical simulation is an effective method to understand the propagation law and response characteristics of seismic waves in complex structures. It has the advantages of more realistic results and no limitation on calculation methods and boundary conditions over numerical simulation. Therefore, it has important applications in the research of the basic law of seismic wave propagation, verification of field seismic exploration methods, design optimization of observation systems, etc. This paper presents a 3D seismic physical modeling system of large double triaxial air-supported positioning and multichannel data acquisition, which …


Study On The Microscopic Mechanism Of The Loess Improved By Quicklime, XIE Xiao, WANG Luyao, DENG Lejuan, ZHANG Guowei 2021 Institute of Land Engineering and Technology, Shaanxi Provincial Land Engineering Construction Group Co., Ltd., Xi'an 710075, China; Key Laboratory of Degraded and Unused Land Consolidation Engineering, Ministry of Natural Resources, Xi'an 710075, China; Shaanxi Provincial Land Consolidation Engineering Technology Research Center, Xi'an 710075, China

Study On The Microscopic Mechanism Of The Loess Improved By Quicklime, Xie Xiao, Wang Luyao, Deng Lejuan, Zhang Guowei

Coal Geology & Exploration

To investigate the influence of lime content on loess strength and its microscopic mechanism, different proportions of lime were used to improve loess. Through direct shear test, mercury intrusion porosimetry and scanning electron microscopy, the strength characteristics and microstructure changes of compacted loess and modified loess with different lime contents were analyzed qualitatively and quantitatively, and the microscopic mechanism of lime-improved loess was analyzed in depth. The results show that the shear strength parameters of lime-improved loess increases first and then decreases with the increase of lime contents. The cohesive force and internal friction angle reach the maximum when the …


Case Study On The Effects Of Seismic Exploration Beneath The Goafs Of Different Ages, ZHANG Zhao, YIN Quanzeng 2021 Coal Geology Geological Team of Hebei Province Bureau, Xingtai 054000, China

Case Study On The Effects Of Seismic Exploration Beneath The Goafs Of Different Ages, Zhang Zhao, Yin Quanzeng

Coal Geology & Exploration

With the continuous development of coal resources, the upper group of coal in some coal mines has been mined out, and it is urgent to solve the detection problem of the lower group of coal. Affected by the goaf formed by the upper group of coal, the seismic energy absorption and scattering attenuation of the lower group of coal are significant, and the signal-to-noise ratio of the data is low. The detection of the lower group of coal under the goaf by 3D seismic exploration is still in the exploration stage. In this paper, the 3D seismic exploration project of …


The Distribution Of Elements In The Alteration Of Feldspatic Minerals, Kıymet DENİZ, Yusuf Kağan KADIOĞLU, Tamer KORALAY, Bahattin GÜLLÜ 2021 Bulletin of the Mineral Research and Exploration

The Distribution Of Elements In The Alteration Of Feldspatic Minerals, Kıymet Deni̇z, Yusuf Kağan Kadioğlu, Tamer Koralay, Bahattin Güllü

Bulletin of the Mineral Research and Exploration

Feldspar (alkali feldspar and plagioclases) and in recent years feldspathoid minerals are used as raw materials in the ceramic-glass industries. The igneous rocks such as granite, syenite and foid syenite which mainly contain these minerals have the potential to be raw materials. Some inclusions within the feldspatic minerals affect extremely negatively the desired values for raw material. In this study, the effective processes in the alteration of feldspatic minerals within the Özvatan foid syenites, the effects of alteration minerals in the raw material were evaluated and the effects of the elements released by alteration on the environment were revealed. The …


Analysis Of Some Farm Driving Variables And Its Relation With Milk Production In A Pastoral Dairy Farm Of Buenos Aires, Argentina, J. L. Rossi, A. Ayala Torales, G. Acosta, V. A. Deregibus 2021 Universidad de Buenos Aires, Argentina

Analysis Of Some Farm Driving Variables And Its Relation With Milk Production In A Pastoral Dairy Farm Of Buenos Aires, Argentina, J. L. Rossi, A. Ayala Torales, G. Acosta, V. A. Deregibus

IGC Proceedings (1997-2023)

The quantity of milk solids produced determines a dairy farm income and contributes to its profit. Total pasture production, forage quality and herd consumption are factors to be managed in this production system. The outcomes of two years were analyzed. Primary production showed its dependence on climatic conditions and use of technological inputs. Forage quality was promoted through interseeding legumes, applying fertilizer and maintaining the pasture young and leafy. Total forage removed by the herd was similar in both years although pasture production decreased. It was possible to cope with seasonal variations in forage production, by varying the grazing pressure …


Effect Of Energetic Supplementation On Forage Losses In An Oat And Italian Ryegrass Pasture Under Continuous Grazing, A. Frizzo, Marta G. da Rocha, M. R. Freitas 2021 Universidade Federal de Santa Maria, Brazil

Effect Of Energetic Supplementation On Forage Losses In An Oat And Italian Ryegrass Pasture Under Continuous Grazing, A. Frizzo, Marta G. Da Rocha, M. R. Freitas

IGC Proceedings (1997-2023)

The experiment was conducted at UFSM-RS to quantify herbage losses in oat and Italian ryegrass mixture under continuous grazing by beef heifers. A continuous grazing method with variable stocking rate was utilized to maintain the same herbage mass, 1500 kg DM/ha, in all treatments. The treatments consisted of levels of energetic supplement (0, 0.7 and 1.4% of LW/day). The pasture was evaluated every 28 days, when forage not suitable for grazing was collected in points previously marked in experimental area. The daily losses of herbage mass were of 22.32, 18.98 and 21.16 kg of DM/ha/day, equivalent to 2.61, 1.91 and …


Dynamics And Production Of Forage In Winter Pasture Under Continuous Grazing With Energetic Supplementation, A. Frizzo, M. R. Freitas, Marta G. da Rocha 2021 Universidade Federal de Santa Maria, Brazil

Dynamics And Production Of Forage In Winter Pasture Under Continuous Grazing With Energetic Supplementation, A. Frizzo, M. R. Freitas, Marta G. Da Rocha

IGC Proceedings (1997-2023)

This experiment was carried out at Federal University of Santa Maria, from July 09 to November 12, 1999 to evaluate the dynamics and production of forage of oat (Avena strigosa Schreb) and italian ryegrass (Lolium multiflorum Lam) mixture. The grazing system used was continuous with variable stocking rate to maintain 1500kg/ha of herbage mass in all treatments. The heifers were subjected to different levels of energetic supplementation. They are 0, 0.7 and 1.4% of LW/day. The pasture of oat and italian ryegrass presented an accumulation rate of 45.7, 55.1 and 50.0 kg of DM/ha /day and a total …


Rotational Grazing Increases Wool And Lamb Production From Phalaris-Subterranean Clover Pastures In South Eastern Australia, A. N. Thompson, D. Borg, J. F. Graham, J. Lamb, G. R. Saul 2021 Agriculture Victoria, Australia

Rotational Grazing Increases Wool And Lamb Production From Phalaris-Subterranean Clover Pastures In South Eastern Australia, A. N. Thompson, D. Borg, J. F. Graham, J. Lamb, G. R. Saul

IGC Proceedings (1997-2023)

Wool and lamb production from different grazing systems was compared in a Mediterranean environment near Hamilton in southeastern Australia. The grazing systems were based on combinations of fertiliser inputs and grazing methods that could promote the growth and persistence of phalaris (Phalaris aquatica) and increase animal production compared to ‘typical’ unimproved pastures. In the first 2 years of this experiment, the most productive systems more than doubled ewe stocking rate and wool production, and more than trebled lamb production per hectare, compared to ‘typical’ unimproved pasture, low fertility, set-stocked systems. The change to a well fertilised phalaris/subterranean clover …


Alien Foraminifers Of The Northern And Northeastern Coastlines Of Cyprus Island, Engin MERİÇ, M. Baki YOKEŞ, İpek F. BARUT, Atike NAZİK, Mustafa ERYILMAZ, Fulya YÜCESOY ERYILMAZ, M. Fatih HÜSEYİNOĞLU, Mustafa KUMRAL, Erol SARI 2021 Bulletin of the Mineral Research and Exploration

Alien Foraminifers Of The Northern And Northeastern Coastlines Of Cyprus Island, Engin Meri̇ç, M. Baki Yokeş, İpek F. Barut, Atike Nazi̇k, Mustafa Eryilmaz, Fulya Yücesoy Eryilmaz, M. Fatih Hüseyi̇noğlu, Mustafa Kumral, Erol Sari

Bulletin of the Mineral Research and Exploration

The study area covers the northern coasts of Cyprus from the Güzelyurt Gulf to the Gazimağusa Gulf. This study was carried out in order to reveal the presence of the alien foraminifera, which are widely distributed in the Eastern Mediterranean particularly Amphistegina lobifera in the study area, and the effects of trace elements on faunal assemblages (foraminifera, ostracod and mollusc). The bottom sediment samples were taken from eighteen different points and depths, the faunal assemblages were examined, and the sediment distribution map of the studied area was made by ICP-MS analysis and geochemical evaluations. 30 genera and 48 species of …


The Carrying Capacity Of Pure And Oversown Giant Star Grass (Cynodon Nlemfuensis Vanderyst) Under Different Stocking Rate In South-Western Islands Of Japan, Yasuhiro Kawamoto, T. Namihira, Y. Imura, M. Nagano 2021 University of the Ryukyus, Japan

The Carrying Capacity Of Pure And Oversown Giant Star Grass (Cynodon Nlemfuensis Vanderyst) Under Different Stocking Rate In South-Western Islands Of Japan, Yasuhiro Kawamoto, T. Namihira, Y. Imura, M. Nagano

IGC Proceedings (1997-2023)

The objective of this study was firstly to know the potential carrying capacity, pasture production, pasture utilization of giant star grass under different stocking rates in intensive rotational grazing system, and to evaluate a carrying capacity of giant star grass (Cynodon nlemfuensis Vanderyst) pasture oversown with annual hybrid ryegrass (Lolium multiflorum X Lolium perenne) on short low productive winter pasture in South-western Islands of Japan. High herbage availability and good quality forage to bring about effective animal productions were produced by using relatively heavy stocking rates of 6 - 8 heads/ha, and achieved optimum pasture utilization of …


Residual Forage And Animal Performance From A Kikuyo Pasture Under Mixed Grazing And Supplementation, F. C. Gómez-Merino, Pedro A. Martínez-Hernández, J. Pérez-Pérez, Alfonso Hernández-Garay 2021 Colegio de Postgraduados, Mexico

Residual Forage And Animal Performance From A Kikuyo Pasture Under Mixed Grazing And Supplementation, F. C. Gómez-Merino, Pedro A. Martínez-Hernández, J. Pérez-Pérez, Alfonso Hernández-Garay

IGC Proceedings (1997-2023)

Five grazing strategies were compared: grazing by ewes only and mixed grazing (ewes + heifers), in mixed grazing heifers received no supplement or one of three supplements. Ruminal undegradable protein (RUP) varied among supplement: 4.25, 9.11 and 9.13%, the supplement with the highest RUP included protected methionine. All supplements were 21% crude protein and 3.0 Mcal/kg of metabolizable energy. Grazing was on kikuyu, ratio was 30 kg of ewe per 100 kg of heifer in the mixed grazing treatments. Experimental grazing lasted 84 days. Variables measured were residual forage, proline content in residual forage and liveweight gains per animal and …


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