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2021

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Articles 151 - 180 of 27663

Full-Text Articles in Physical Sciences and Mathematics

Experimental Study On Transient Electromagnetic Method With A Conical Source, Yang Haiyan, Liu Zhixin, Zhang Hua, Chen Xiao, Lian Zhe, Wang Ling, Yang Fujie Dec 2021

Experimental Study On Transient Electromagnetic Method With A Conical Source, Yang Haiyan, Liu Zhixin, Zhang Hua, Chen Xiao, Lian Zhe, Wang Ling, Yang Fujie

Coal Geology & Exploration

A new transmitter device-conical source has been proved theoretically to have several advantages for transient electromagnetic sounding. To verify application ability of conical source, two kinds of transmitter devices were designed and made, and the experimental studies on surface and in mine roadway were carried out. By applying high density resistivity achievements in surface experiment, the detecting results using conical source and multi-coils were compared. The results show that the description of strata resistivity with conical source is better than that with multi-coils. One fault was identified and the strike and position of which matches the high density resistivity result …

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New Method And Optimization Research On Water Sealing Outside Casing Based On Water-Swelling Rubber For Stratified Pumping, Zheng Xianghua, Yuan Wei, Luo Yunxiang, Cheng Cong Dec 2021

New Method And Optimization Research On Water Sealing Outside Casing Based On Water-Swelling Rubber For Stratified Pumping, Zheng Xianghua, Yuan Wei, Luo Yunxiang, Cheng Cong

Coal Geology & Exploration

Stratified pumping test is a key technique for hydrogeological exploration. To solve the problems of low efficiency and poor reliability and controllability of the traditional water-sealing methods outside casing for stratified pumping, a water-swelling rubber was developed based on high water absorption of the sodium polyacrylate resin, and a new approach based on water-swelling rubber was proposed and optimized by the response surface methodology in this paper. With the water swelling ratio of the rubber as response index, a surrogate model was constructed by the Box-Behnken experimental design to study the influence of different process parameters, working condition parameters, and …

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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 Dec 2021

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 …

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Development And Prospect Of Intelligent Drilling Technology And Equipment For Underground Coal Mines In China, Li Quanxin, Liu Fei, Fang Jun Xi'an Research Institute Co., Ltd., China Coal Technology And Engineering Group Corp., Xi'an 710077, China, Liu Jianlin, Chu Zhiwei Dec 2021

Development And Prospect Of Intelligent Drilling Technology And Equipment For Underground Coal Mines In China, Li Quanxin, Liu Fei, Fang Jun Xi'an Research Institute Co., Ltd., China Coal Technology And Engineering Group Corp., Xi'an 710077, China, Liu Jianlin, Chu Zhiwei

Coal Geology & Exploration

The intelligent drilling technology and equipment are important part of the intelligent construction of coal mine, and it is the advanced technology and equipment urgently needed by coal mine enterprises to further promote the work of reducing personnel and increasing efficiency. The phased achievements of underground intelligent drilling technology and equipment during the 13th five-year plan are systematically summarized, and the development status of key technical equipment such as automatic drilling rig, parameter monitoring of measurement while drilling(MWD) system, rotary steerable system are introduced. The key factors restricting the research and development (R & D) and application of intelligent drilling …

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Table Of Contents, The Editors Dec 2021

Table Of Contents, The Editors

Coal Geology & Exploration

No abstract provided.

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Geochemical Characteristics Of Marine-Continental Transitional Facies Shale And Shale Gas In Linxing Area, Chen Xin, Wu Peng, Gao Jixian, Hu Weiqiang, Ding Wangui, Li Yangbing, Liu Xueqing, Ma Litao, Liu Cheng, Kong Wei, Cao Di, Chen Jianqi, Li Yong Dec 2021

Geochemical Characteristics Of Marine-Continental Transitional Facies Shale And Shale Gas In Linxing Area, Chen Xin, Wu Peng, Gao Jixian, Hu Weiqiang, Ding Wangui, Li Yangbing, Liu Xueqing, Ma Litao, Liu Cheng, Kong Wei, Cao Di, Chen Jianqi, Li Yong

Coal Geology & Exploration

In order to reveal the geochemical characteristics of shale and shale gas on the east edge of Ordos Basin, thin section identification, full rock and clay content, scanning electron microscope, organic carbon, rock pyrolysis, kerogen macerals, and kerogen carbon isotopes were tested, and the gas component and carbon isotopes composition of shale were analyzed. The results show that the mineral component of the transitional facies shale in Linxing area is mainly quartz and clay minerals, containing a small amount of calcite, plagioclase, potassium feldspar, dolomite and pyrite. Affected by the mineral genesis and deposition environment, different mineral components and organic …

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Geological Characteristics And Reservoir-Forming Potential Of Shale Gas Of Transitional Facies In Linxing Area, Eastern Margin Of Ordos Basin, Wu Peng, Cao Di, Zhu Guanghui, Liu Xueqing, Li Yong, Li Yangbing, Hu Weiqiang, Liu Zaizhen, Kong Wei, Fei Jingliang Dec 2021

Geological Characteristics And Reservoir-Forming Potential Of Shale Gas Of Transitional Facies In Linxing Area, Eastern Margin Of Ordos Basin, Wu Peng, Cao Di, Zhu Guanghui, Liu Xueqing, Li Yong, Li Yangbing, Hu Weiqiang, Liu Zaizhen, Kong Wei, Fei Jingliang

Coal Geology & Exploration

Shale gas of transitional facies is the important replacing area for increase of shale gas reserves and production. On the basis of the experiment and research data of shale of transitional facies of Linxing area in the eastern margin of Ordos Basin, by selecting the strata series of Shanxi Formation, Taiyuan Formation and Benxi Formation as the research object, from the sedimentary environments, shale distribution, organic geochemical characteristics, mineralogy, physical characteristics and gas-bearing characteristics, etc., the geology characteristics of the shale gas transitional facies in the study area were summarized and dissected systematically to analyze its enrichment and reservoir-forming potential. …

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Qualitative-Quantitative Multi Scale Characteristics Of Shale Pore Structure From Upper Paleozoic Coal-Measures In Linxing Area, Liu Cheng, Ding Wangui, Zhang Jian, Chen Xin, Wu Peng, Liu Xueqing, Li Yangbing, Ma Litao, Hu Weiqiang, Kong Wei, Li Yong Dec 2021

Qualitative-Quantitative Multi Scale Characteristics Of Shale Pore Structure From Upper Paleozoic Coal-Measures In Linxing Area, Liu Cheng, Ding Wangui, Zhang Jian, Chen Xin, Wu Peng, Liu Xueqing, Li Yangbing, Ma Litao, Hu Weiqiang, Kong Wei, Li Yong

Coal Geology & Exploration

In order to reveal the micro-pore structure characteristics of marine-continental transitional shale and its main controlling factors in the eastern margin of Ordos Basin, and to enrich the understanding of pore development characteristics and pore structure of marine-continental transitional coal-bearing shale in the block, scanning electron microscope, high-pressure mercury injection and liquid nitrogen adsorption analysis were used to characterize the micro-pore structure characteristics of shale in Linxing area. Furthermore, porosity, total content of organic carbon, mineral content, clay relative content and organic matter maturity were tested to study the main controlling factors of development of shale pore structure. The results …

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Characteristics Of Shallow Coal Measure Gas Reservoir And Key Technologies Of Exploration And Development In Yaojie Mining Area, Du Xinfeng, Yuan Chongliang, Wang Zhengxi, Wang Junde, Li Shibing, Liu Jingdan, He Xiuqing, Zhang Tianguo, Shan Yuanwei, Fang Jiawei Dec 2021

Characteristics Of Shallow Coal Measure Gas Reservoir And Key Technologies Of Exploration And Development In Yaojie Mining Area, Du Xinfeng, Yuan Chongliang, Wang Zhengxi, Wang Junde, Li Shibing, Liu Jingdan, He Xiuqing, Zhang Tianguo, Shan Yuanwei, Fang Jiawei

Coal Geology & Exploration

The exploration and development of coal measures gas can not only effectively improve the single well production of coalbed methane in coal mining areas, reduce the waste of resources, but also alleviate the energy crisis in China, reduce coal mine gas accidents, protect the atmospheric environment, and contribute to the realization of carbon peak and carbon neutralization. Based on the shallow coal measure gas development demonstration project in the third mining area of Haishiwan mine field, the characteristics of coal measure gas reservoirs in Yaojie mining area are analyzed, and the key technologies for coal-measure gas exploration and development are …

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Cbm Well Drainage Data-Based Dynamic Inversion Study Of Reservoir Gas Content, Ma Dongmin, Ji Yusong, Chen Yue, Zheng Chao, Teng Jinxiang, Ma Zhuoyuan, Xiao Jialong Dec 2021

Cbm Well Drainage Data-Based Dynamic Inversion Study Of Reservoir Gas Content, Ma Dongmin, Ji Yusong, Chen Yue, Zheng Chao, Teng Jinxiang, Ma Zhuoyuan, Xiao Jialong

Coal Geology & Exploration

The gas content of coal reservoir is the core parameter of coalbed methane production. There is an error between the measured gas content and the real gas content of coal reservoir. In this paper, based on the gas production of Haishiwan coalbed methane wells in different periods and the decrease of the "constant volume" of the gas content of coal reservoirs, the real-time gas content of coal reservoirs is inverted, and the change rule of the real-time gas content in the process of coalbed methane well drainage is explored. The results show that: (1) The gas content of coal reservoir …

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Physical Modeling Of Seismic Response For The Coal Seams Of Yan'an Formation In Loess Tableland Of North China, Xing Tingdong, Xue Shigui, Li Xiaowei, Suo Chonghui, Wang Huiming, Jiao Yanyan Dec 2021

Physical Modeling Of Seismic Response For The Coal Seams Of Yan'an Formation In Loess Tableland Of North China, Xing Tingdong, Xue Shigui, Li Xiaowei, Suo Chonghui, Wang Huiming, Jiao Yanyan

Coal Geology & Exploration

A seismic physical simulation is carried out for the complex seismic response of the coal seam of Yan'an Formation in the loess tableland. First, the physical model materials for the dry layer near the surface of the loess tableland and the coal seam are developed. After several tests, a mixture of silicone rubber with silicon aerogel powder is selected to simulate the surface of the loess tableland, and the mixture with ultra-fine carbon powder added to silicone rubber is used to simulate the low-speed and low-density coal seam. Through the methods of molds control layer, layer by layer pouring, three-dimensional …

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3d Seismic Physical Modeling Acquisition Technology And Its Application, Liu Qiang, Shi Xianxin, Hu Jiwu, Dong Ruijing, Lian Chenguang Dec 2021

3d Seismic Physical Modeling Acquisition Technology And Its Application, Liu Qiang, Shi Xianxin, Hu Jiwu, Dong Ruijing, Lian Chenguang

Coal Geology & Exploration

Seismic physical modeling acts as a bridge between the research on seismic theoretical methods and actual seismic exploration, which is an important means of studying the propagation law of the elastic wave field and verifying the processing and interpretation methods. It plays an important role of theoretical supporting in the field of oil & gas seismic exploration. There is a great difference between coalfield and oil & gas in seismic exploration attributes, and no professional automatic seismic physical modeling system has been built in the field of coal field seismic exploration. Therefore, a large professional 3D seismic physical modeling system …

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Design And Construction Of A Seismic Physical Model Of Room-Pillar Goafs In Shallow Coal Seams, Wang Pan, Zhu Shujie, Jia Qian, Jian Benqi, Lian Miaomiao, Dong Ruijing Dec 2021

Design And Construction Of A Seismic Physical Model Of Room-Pillar Goafs In Shallow Coal Seams, Wang Pan, Zhu Shujie, Jia Qian, Jian Benqi, Lian Miaomiao, Dong Ruijing

Coal Geology & Exploration

In view of the problem of low detection accuracy of room-pillar goafs in shallow coal seams in northern Shaanxi, the seismic physical model is designed for physical simulation according to the principle of similarity ratio of geometry size and wave impedance. Through a large number of ratio tests of similar materials, the ratio of epoxy resin and silicone rubber is determined as 1 : 1.2 for similar materials of low velocity loess layer, 1 : 0.2 : 0.6 for epoxy resin, silicone rubber and talc for mudstone, 1 : 0.4 for epoxy resin and silicone rubber for coal seams, 1 …

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Discussion On The Recommended Models For Resource Reuse Of Closed Coal Mines In Main Mining Areas Of Hebei Province, Yin Quanzeng, Chen Zhongshan, Feng Qiyan, Geng Lijuan, Lian Lixun, Li Fang, Liu Ning Dec 2021

Discussion On The Recommended Models For Resource Reuse Of Closed Coal Mines In Main Mining Areas Of Hebei Province, Yin Quanzeng, Chen Zhongshan, Feng Qiyan, Geng Lijuan, Lian Lixun, Li Fang, Liu Ning

Coal Geology & Exploration

The evaluation and the utilization of the resources of the closed coal mines have dual benefits of resources and environment, and can provide a transformation and development path for coal mining enterprises. Based on the investigation of the resources of the closed coal mines in the main mining areas of Hebei Province, through the summary of the typical cases of the resources reuse of the closed coal mines at home and abroad and in Hebei Province, this paper sums up 7 types and 19 kinds of recommended modes of the resources reuse of the closed coal mines in Hebei Province, …

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Plastic Deformation-Based Constitutive Relation Of Coal Damage And Permeability Model, Wu Xuehai, Li Bobo, Wang Xin, Gao Zheng, Li Jianhua, Xu Jiang Dec 2021

Plastic Deformation-Based Constitutive Relation Of Coal Damage And Permeability Model, Wu Xuehai, Li Bobo, Wang Xin, Gao Zheng, Li Jianhua, Xu Jiang

Coal Geology & Exploration

Coal and gas outburst induced by mining disturbance is one of the main gas dynamic disasters in coal mine production. In order to systematically explore the evolution characteristics of coal damage and the law of gas seepage under mining disturbance, the whole stress strain–seepage experiment under different gas pressures was carried out. The generalized Hooke's law was modified by considering the effects of gas adsorption and thermal expansion, the plastic deformation-based constitutive relation of coal damage was established, and the piecewise permeability model considering the damage was further constructed. The results shown that the coal permeability can be divided into …

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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 Dec 2021

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 …

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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 Dec 2021

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 …

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Interfacial Shear Behavior Of Gabion Reinforced Coal Gangue And Stability Of Embankment Slope, Yang Guolin, Chen Zi'ang, Duan Junyi, Zhang Yu, Zhang Zhen Dec 2021

Interfacial Shear Behavior Of Gabion Reinforced Coal Gangue And Stability Of Embankment Slope, Yang Guolin, Chen Zi'ang, Duan Junyi, Zhang Yu, Zhang Zhen

Coal Geology & Exploration

In order to make full use of coal gangue generated in coal mining and support the carbon neutral policy, the road section K128+573–K128+740 of Anshao Highway (Anhua-shaoyang, Hunan Province)was filled by coal gangue, and the embankment slope was enhanced by gabion net. The basic characteristics of coal gangue were obtained by its chemical composition and gradation, and shear characteristics of gabion reinforced coal gangue were tested by large-scale direct shearing instrument. Finally, the influence of reinforcement and its method on the stability of reinforced coal gangue embankment was found out by finite difference method. The experimental results show that after …

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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 Dec 2021

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 …

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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 Dec 2021

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 …

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Evolution Law Of The Phreatic Aquifer Water Table In The Water Intake Area Of South-To-North Water Diversion Central Line In Henan Province, Jing Zhaokai, Yan Qing, Xiao Hang, Wang Panpan, Wang Huan, Li Yang Dec 2021

Evolution Law Of The Phreatic Aquifer Water Table In The Water Intake Area Of South-To-North Water Diversion Central Line In Henan Province, Jing Zhaokai, Yan Qing, Xiao Hang, Wang Panpan, Wang Huan, Li Yang

Coal Geology & Exploration

The water supply of the South-to-North Water Diversion has presented a significant impact on the phreatic aquifer water table and the water consumption structure in the intake area of Henan Province. This paper firstly reviews the previous changes of groundwater level burial depth in the plain area of Henan Province, and by collecting and counting the monitoring results of shallow groundwater level in the receiving area of Henan Province from 2008 to 2018, we quantified and partitioned the changes of shallow groundwater level in the receiving area of Henan Province before and after the water supply of the South-to-North Water …

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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 Dec 2021

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 …

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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 Dec 2021

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 …

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Mechanism And Effect Analysis Of Enhanced Gas Drainage With Large Diameter Double Boreholes, Zhang Chunhua, Zhang Zijian, Nian Jun, Jiao Dengming Dec 2021

Mechanism And Effect Analysis Of Enhanced Gas Drainage With Large Diameter Double Boreholes, Zhang Chunhua, Zhang Zijian, Nian Jun, Jiao Dengming

Coal Geology & Exploration

To study the mechanism of enhanced gas drainage with large diameter double boreholes, numerical models of single holes with different diameters and double ø350 mm holes were established by using the RFPA2D-Gas software in working face 30110 of Shiquan Coal Mine, Shanxi Province. Stress distribution, damage and fracture, gas permeability evolution and gas migration law of the coal around the hole were analyzed, and then the extraction effect of double ø350 mm holes was investigated. Simulation results show that the pressure relief radii of the ø100 mm, ø250 mm, ø350 mm and double ø350 mm holes are 0.25 …

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A Proof Of A Generalization Of Niven's Theorem Using Algebraic Number Theory, Caroline Nunn Dec 2021

A Proof Of A Generalization Of Niven's Theorem Using Algebraic Number Theory, Caroline Nunn

Rose-Hulman Undergraduate Mathematics Journal

Niven’s theorem states that the sine, cosine, and tangent functions are rational for only a few rational multiples of π. Specifically, for angles θ that are rational multiples of π, the only rational values of sin(θ) and cos(θ) are 0, ±½, and ±1. For tangent, the only rational values are 0 and ±1. We present a proof of this fact, along with a generalization, using the structure of ideals in imaginary quadratic rings. We first show that the theorem holds for the tangent function using elementary properties of Gaussian integers, before extending the approach to other imaginary quadratic rings. We …

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Measurement Of Differential Branching Fractions Of Inclusive B →Xuℓ+Νℓ Decays, L. Cao, W. Sutcliffe, R. Van Tonder, F. U. Bernlochner, I. Adachi, H. Aihara, D. M. Asner, T. Aushev, R. Ayad, V. Babu, S. Bahinipati, P. Behera, K. Belous, J. Bennett, M. Bessner, T. Bilka, J. Biswal, A. Bobrov, M. Bračko Dec 2021

Measurement Of Differential Branching Fractions Of Inclusive B →Xuℓ+Νℓ Decays, L. Cao, W. Sutcliffe, R. Van Tonder, F. U. Bernlochner, I. Adachi, H. Aihara, D. M. Asner, T. Aushev, R. Ayad, V. Babu, S. Bahinipati, P. Behera, K. Belous, J. Bennett, M. Bessner, T. Bilka, J. Biswal, A. Bobrov, M. Bračko

Faculty and Student Publications

The first measurements of differential branching fractions of inclusive semileptonic B→Xuℓ+νℓ decays are performed using the full Belle data set of 711 fb-1 of integrated luminosity at the (4S) resonance and for ℓ=e, μ. With the availability of these measurements, new avenues for future shape-function model-independent determinations of the Cabibbo-Kobayashi-Maskawa matrix element |Vub| can be pursued to gain new insights in the existing tension with respect to exclusive determinations. The differential branching fractions are reported as a function of the lepton energy, the four-momentum-transfer squared, light-cone momenta, the hadronic mass, and the hadronic mass squared. They are obtained by subtracting …

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Intercomparison Of Salinity Products In The Beaufort Gyre And Arctic Ocean, Sarah B. Hall, Bulusu Subrahmanyam, James H. Morison Dec 2021

Intercomparison Of Salinity Products In The Beaufort Gyre And Arctic Ocean, Sarah B. Hall, Bulusu Subrahmanyam, James H. Morison

Faculty Publications

Salinity is the primary determinant of the Arctic Ocean’s density structure. Freshwater accumulation and distribution in the Arctic Ocean have varied significantly in recent decades and certainly in the Beaufort Gyre (BG). In this study, we analyze salinity variations in the BG region between 2012 and 2017. We use in situ salinity observations from the Seasonal Ice Zone Reconnaissance Surveys (SIZRS), CTD casts from the Beaufort Gyre Exploration Project (BGP), and the EN4 data to validate and compare with satellite observations from Soil Moisture Active Passive (SMAP), Soil Moisture and Ocean Salinity (SMOS), and Aquarius Optimally Interpolated Sea Surface Salinity …

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Negative Order Kdv Equation With No Solitary Traveling Waves, Miguel Rodriguez, Jing Li, Zhijun Qiao Dec 2021

Negative Order Kdv Equation With No Solitary Traveling Waves, Miguel Rodriguez, Jing Li, Zhijun Qiao

School of Mathematical & Statistical Sciences Faculty Publications

We consider the negative order KdV (NKdV) hierarchy which generates nonlinear integrable equations. Selecting different seed functions produces different evolution equations. We apply the traveling wave setting to study one of these equations. Assuming a particular type of solution leads us to solve a cubic equation. New solutions are found, but none of these are classical solitary traveling wave solutions.

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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 Dec 2021

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 (1977-2023)

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 …

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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 Dec 2021

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 (1977-2023)

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 …

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