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Cattle And Sheep Mixed Grazing: 1. Species Equivalence, R. D. Améndola-Massiotti, S. J. C. González-Montagna, Pedro A. Martínez-Hernández Jun 2023

Cattle And Sheep Mixed Grazing: 1. Species Equivalence, R. D. Améndola-Massiotti, S. J. C. González-Montagna, Pedro A. Martínez-Hernández

IGC Proceedings (1977-2023)

The effects of mixed grazing of cattle and sheep depend on stocking rate (SR) and species ratio (Nicol, 1997). Calculations of SR and species ratio require the use of species equivalence. Equivalents are often estimated in terms of intake requirements related to live weight (LW), while maintenance energy requirements are calculated on the basis of LW0.75. Freer (1981) stated that LW0..9 would be more appropriate for comparisons of intake requirements for maintenance of sheep and cattle. Nonetheless, Nolan & Connolly (1977) stated that the equivalent is system-specific and depends on the species being considered. The objective of …

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Diversity Of Diet Composition Decreases With Conjoint Grazing Of Cattle With Sheep And Goats, A. M. Nicol, M. B. Soper, A. V. Stewart Jun 2023

Diversity Of Diet Composition Decreases With Conjoint Grazing Of Cattle With Sheep And Goats, A. M. Nicol, M. B. Soper, A. V. Stewart

IGC Proceedings (1977-2023)

Conjoint or mixed grazing can affect the diet selected by each species (Nicol & Collins, 1990). Diet similarity coefficients are often used to compare pairs of diets (Krebs, 1999). However this approach is awkward when a number of contrasts are required in a multifactorial comparison. Species diversity is a descriptor of a particular environment. Many models provide an estimate of species diversity, the most common of these being a log-normal distribution (Tokeshi, 1996). We tested whether this model could be applied to dietary components selected from a pasture, and thus provide a coefficient of dietary diversity for the individual diets …

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Elasticity Of Ingestive Behaviour And Intake In Sheep Associated With Food Diversity On Plurispecific Swards, C. Cortes, J. C. Damasceno, G. Bechet, J. Jamot, S. Prache Jun 2023

Elasticity Of Ingestive Behaviour And Intake In Sheep Associated With Food Diversity On Plurispecific Swards, C. Cortes, J. C. Damasceno, G. Bechet, J. Jamot, S. Prache

IGC Proceedings (1977-2023)

Animals on heterogeneous swards generally opt for a varied diet. This may stimulate their intake, unless searching constraints limit intake rate (Champion et al., 1998). However the management of plurispecific swards presents a risk of overgrazing the preferred species and undergrazing the less-preferred species. This study aimed to test the effect of type of diversity and type of management on the elasticity of ingestive behaviour and intake in sheep.

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Theoretical Considerations On A One-Parameter Approach To Compare Actual And Estimated Compositions Of Multi-Component Diets, C. Elwert, M. Rodehutscord Jun 2023

Theoretical Considerations On A One-Parameter Approach To Compare Actual And Estimated Compositions Of Multi-Component Diets, C. Elwert, M. Rodehutscord

IGC Proceedings (1977-2023)

The composition of ingested herbage mixtures can be estimated using the alkane technique (Dove & Moore, 1995), with the accuracy of the estimate assessed by linear regression of estimated and actual proportions of the dietary components (Dove, 1992). However, although the linear regression might not differ from the line of equality, large discrepancies may occur within individual components (Hoebee et al., 1998). This paper presents an approach to compare actual and estimated diet compositions using only one parameter.

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Estimating Pasture Intake By Dairy Cows, Dennis R. Cosgrove, D. P. Cooper Jun 2023

Estimating Pasture Intake By Dairy Cows, Dennis R. Cosgrove, D. P. Cooper

IGC Proceedings (1977-2023)

Proper nutrient management planning minimizes the environmental impact of manure from dairy farms. Manure output from dairy cows can be predicted from feed intake (Wilkerson et al., 1997). Weighing feed and refusals each day can determine accurately the feed intake of dairy cows in confinement. Intake determination is more difficult for dairy cows on pasture (Vasquez & Smith, 2000). As part of a larger study aimed at estimating manure production of dairy cows on pasture, this study compares 3 methods for estimating pasture yield and feed intake.

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An Evaluation Of The N-Alkane Technique For Determining Diet Composition In Animals Grazing Complex Swards, M. D. Fraser, J. M. Moorby, V. J. Theobald, R. Jones Jun 2023

An Evaluation Of The N-Alkane Technique For Determining Diet Composition In Animals Grazing Complex Swards, M. D. Fraser, J. M. Moorby, V. J. Theobald, R. Jones

IGC Proceedings (1977-2023)

The n-alkane profiles of epicuticular waxes derived from different plant species are sufficiently distinct to allow assessment of the proportions of different herbages in two-component mixtures including perennial ryegrass/white clover, heather/hill grass and rush/perennial ryegrass (Dove & Mayes, 1996). Evidence suggests the reliability of such estimates declines as the number of different dietary components increases. However, recent studies have shown analysis of additional compounds, including long-chain fatty alcohols, may improve discrimination between different dietary components. The aim of this experiment was to quantify the accuracy of such methods for determining the diet composition of animals grazing complex swards.

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Estimating Pasture Intake By Cattle Using Alkanes And A Known Amount Of Supplement, E. Charmley, J. L. Duynisveld, H. Dove Jun 2023

Estimating Pasture Intake By Cattle Using Alkanes And A Known Amount Of Supplement, E. Charmley, J. L. Duynisveld, H. Dove

IGC Proceedings (1977-2023)

The alkane ratio method for estimating pasture intake involves calculating the fecal ratio of plant (endogenous) and exogenous alkanes. This method is effective for sheep, although the delivery mechanism for the exogenous alkanes has presented challenges in cattle (Charmley et al. 2003). Dove et al. (2003) have shown that the relative concentration of components in a mixed diet can be estimated from fecal alkane concentrations using least squares methods. Further, if the amount of one dietary component is known, then the amount of all components, and hence intake, can be determined. In this trial beeswax was added to …

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Using The N-Alkane Technique To Estimate The Herbage Intake And Diet Composition Of Cattle Grazing A Miscanthus Sinensis Grassland, Y. J. Zhang, Y. Togamura, K. Otsuki Jun 2023

Using The N-Alkane Technique To Estimate The Herbage Intake And Diet Composition Of Cattle Grazing A Miscanthus Sinensis Grassland, Y. J. Zhang, Y. Togamura, K. Otsuki

IGC Proceedings (1977-2023)

Plant wax alkanes are now widely used as marker substances (Dove & Mayes 1991) for the estimation of forage intake and diet composition of grazing herbivores. The objective of this study was to evaluate this method with cattle grazing a M. sinensis grassland in Japan.

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Rich Information In The Acoustic Signals From Feeding And Grazing In Ruminants, Montague W. Demment, J. R. Galli, Carlos A. Cangiano, Emilio A. Laca Jun 2023

Rich Information In The Acoustic Signals From Feeding And Grazing In Ruminants, Montague W. Demment, J. R. Galli, Carlos A. Cangiano, Emilio A. Laca

IGC Proceedings (1977-2023)

Because of their impact on productivity and the environment, feeding behaviour, ingestion and rumination are critical to understand intake in grazing ruminants. Many systems, mainly mechanical, have been developed to measure ingestive behaviour. However, these systems have problems, including mechanical failure and the inability to distinguish between the complex jaw movements of prehension and ingestion (Laca et al., 1994). The sounds generated by these behaviours are rich in information that holds potential not only to distinguish and count behaviours, but also identify aspects of the nature of the foods ingested.

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The Sound Of Chewing, J. R. Galli, Carlos A. Cangiano, Emilio A. Laca, M. W. Demment Jun 2023

The Sound Of Chewing, J. R. Galli, Carlos A. Cangiano, Emilio A. Laca, M. W. Demment

IGC Proceedings (1977-2023)

Acoustic biotelemetry has been proposed as a way to count ingestive bites and chews of grazing animals. Recent work has indicated the possibility that detailed analysis of 'sounds of chewing' contains information about other characteristics of the ingestive process that can be used to study grazing behaviour of free ranging animals (Laca & Wallis DeVries, 2000), or to monitor stall-fed animals in more detail.

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Development Of A 2-Dimensional Video-Acoustic Tool For Monitoring Bite Placement, Wendy Griffiths, V. Alchanatis, R. Nitzan, V. Ostrovsky, E. Ben-Moshe, R. Yonatan, S. Brenner, H. Baram, E. D. Ungar Jun 2023

Development Of A 2-Dimensional Video-Acoustic Tool For Monitoring Bite Placement, Wendy Griffiths, V. Alchanatis, R. Nitzan, V. Ostrovsky, E. Ben-Moshe, R. Yonatan, S. Brenner, H. Baram, E. D. Ungar

IGC Proceedings (1977-2023)

Studies of grazing behaviour conducted at the spatial scale of a feeding station demonstrate that intake rate declines with increasing depletion, a response attributed to an increase in bite overlap (Ginnett et al., 1999; Ungar et al., 2001). In order to understand the rules that govern bite placement, a methodology is required that can map the sequential placement of bites on the sward surface. We developed a video-acoustic tool to achieve this and report the findings of using the tool on small uniform patches of herbage.

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Spatial Heterogeneity Of Seasonal Grazing Pressure Created By Herd Movement Patterns On Hilly Rangelands Using Gps And Gis, A. I. Arnon, E. D. Ungar, T. Svoray, A. Perevolotsky, M. Shachak, H. Baram, R. Yonatan, E. Ben-Moshe, S. Brenner, D. Barkai Jun 2023

Spatial Heterogeneity Of Seasonal Grazing Pressure Created By Herd Movement Patterns On Hilly Rangelands Using Gps And Gis, A. I. Arnon, E. D. Ungar, T. Svoray, A. Perevolotsky, M. Shachak, H. Baram, R. Yonatan, E. Ben-Moshe, S. Brenner, D. Barkai

IGC Proceedings (1977-2023)

The spatial heterogeneity of grazing pressure on extensive rangelands has management implications (Adler et al., 2001) but it has traditionally been difficult to quantify. Combination of technologies based on GPS (Global Positioning System) and GIS (Geographic Information Systems) is a quantum leap in our ability to address this issue. These tools were used to estimate the spatial heterogeneity of grazing pressure at a farm scale, and examine the relation between local landscape features and local grazing pressure.

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Chew-Bites, Jaw Movement Allocation And Bite Rate In Grazing Cattle As Identified By Acoustic Monitoring, E. D. Ungar, N. Ravid, T. Zada, E. Ben-Moshe, R. Yonatan, S. Brenner, H. Baram, A. Genizi Jun 2023

Chew-Bites, Jaw Movement Allocation And Bite Rate In Grazing Cattle As Identified By Acoustic Monitoring, E. D. Ungar, N. Ravid, T. Zada, E. Ben-Moshe, R. Yonatan, S. Brenner, H. Baram, A. Genizi

IGC Proceedings (1977-2023)

Bite rate derives from the time budget of the biting and chewing processes of intake, which are both performed by jaw movements. A new type of jaw movement was revealed by acoustic monitoring in cattle - the "chew-bite" -which chews herbage already in the mouth and harvests fresh herbage with the same jaw movement (Laca et al., 1992). Chew-biting should enable the animal to reduce the total number of jaw movements performed per bite without reducing the number of chews per bite. We examined the variation among individuals in the allocation of jaw movements between the three types, and …

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Incorporation Of Carbon Dioxide Production And Transport Module Into A Soil-Plant-Atmosphere Continuum Model, Sahila Beegum, Wenguang Sun, Dennis Timlin, Zhuangji Wang, David Fleisher, Vangimalla R. Reddy, Chittaranjan Ray Jun 2023

Incorporation Of Carbon Dioxide Production And Transport Module Into A Soil-Plant-Atmosphere Continuum Model, Sahila Beegum, Wenguang Sun, Dennis Timlin, Zhuangji Wang, David Fleisher, Vangimalla R. Reddy, Chittaranjan Ray

Nebraska Water Center: Faculty Publications

Carbon dioxide release from agricultural soils is influenced by multiple factors, including soil (soil properties, soil-microbial respiration, water content, temperature, soil diffusivity), plant (carbon assimilation, rhizosphere respiration), atmosphere (climate, atmospheric carbon dioxide), etc. Accurate estimation of the carbon dioxide (CO2) fluxes in the soil and soil respiration (CO2 flux between soil and atmosphere) requires a process-based modeling approach that accounts for the influence of all these factors. In this study, a module for CO2 production via root and microbial respiration and diffusion-based carbon dioxide transport is developed and integrated with MAIZSIM (a process-based maize crop growth …

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Wildlife Ecological Risk Assessment In The 21st Century: Promising Technologies To Assess Toxicological Effects, Barnett A. Rattner, Thomas G. Bean, Val R. Beasley, Philippe Berny, Karen M. Eisenreich, John E. Elliott, Margaret L. Eng, Phyllis C. Fuchsman, Mason D. King, Rafael Mateo, Carolyn B. Meyer, Jason M. O'Brien, Christopher J. Salice Jun 2023

Wildlife Ecological Risk Assessment In The 21st Century: Promising Technologies To Assess Toxicological Effects, Barnett A. Rattner, Thomas G. Bean, Val R. Beasley, Philippe Berny, Karen M. Eisenreich, John E. Elliott, Margaret L. Eng, Phyllis C. Fuchsman, Mason D. King, Rafael Mateo, Carolyn B. Meyer, Jason M. O'Brien, Christopher J. Salice

United States Geological Survey: Staff Publications

Despite advances in toxicity testing and the development of new approach methodologies (NAMs) for hazard assessment, the ecological risk assessment (ERA) framework for terrestrial wildlife (i.e., air‐breathing amphibians, reptiles, birds, and mammals) has remained unchanged for decades. While survival, growth, and reproductive endpoints derived from whole-animal toxicity tests are central to hazard assessment, nonstandard measures of biological effects at multiple levels of biological organization (e.g., molecular, cellular, tissue, organ, organism, population, community, ecosystem) have the potential to enhance the relevance of prospective and retrospective wildlife ERAs. Other factors (e.g., indirect effects of contaminants on food supplies and infectious disease processes) …

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Table Of Contents, The Editors Jun 2023

Table Of Contents, The Editors

Coal Geology & Exploration

No abstract provided.

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Preparation And Properties Of Acrylate Grouting Material Used In Coal Mine, Zeng Juanjuan, Li Huizhi, Wei Daidong, Xue Wei, Zhu Kaipeng Jun 2023

Preparation And Properties Of Acrylate Grouting Material Used In Coal Mine, Zeng Juanjuan, Li Huizhi, Wei Daidong, Xue Wei, Zhu Kaipeng

Coal Geology & Exploration

Water leakage control on the coal mine roof is an inevitable challenge in the process of coal mining. In this regard, chemical grouting provides an effective method to solve this problem. Specifically, acrylate grouting materials were prepared using the synthesized magnesium acrylate solution, cross-linking agent, initiator, and accelerator as the raw materials. Based on this, the effects of the concentration of magnesium acrylates, the type and dosage of crosslinking agent and the dosage of initiator on the properties of the gels of the acrylate grouting materials were investigated. The test results indicate that the type and dosage of crosslinking agent …

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Current Situation And Development Trend Of Pressure-Relief Gas Extraction In The Protective Layer Mining In Coal Mines In China, Xue Junhua, Xiao Jian, Du Xuanhong, Shi Yu Jun 2023

Current Situation And Development Trend Of Pressure-Relief Gas Extraction In The Protective Layer Mining In Coal Mines In China, Xue Junhua, Xiao Jian, Du Xuanhong, Shi Yu

Coal Geology & Exploration

Deep coal mining in China is seriously restricted by factors including high stress, high gas pressure, and low coal seam permeability. Moreover, with the gradual deterioration of the mining conditions of deep coal seams, it is increasingly difficult to control the gas in these coal seams. Fortunately, the pressure-relief mining of protective layers serves as an efficient way to control gas and eliminate coal and gas outbursts. To meet the demand of practical projects, this paper reviews the studies on the mining technology for protective layers, the law of change in the stress of protected layers, the evolutionary law of …

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Effects Of Increasing Sintering Pressure On The Performance Of Impregnated Diamond Bit, Yang Zhan, Tan Songcheng, Fang Xiaohong, Yang Kaihua Jun 2023

Effects Of Increasing Sintering Pressure On The Performance Of Impregnated Diamond Bit, Yang Zhan, Tan Songcheng, Fang Xiaohong, Yang Kaihua

Coal Geology & Exploration

The matrix formulas of conventional hot-pressed impregnated diamond bits are mostly elemental metal systems, using WC or YG8 as the skeleton materials, Cu alloys as the bonding materials, and Ni, Co, Fe and Mn as the intermediate materials. Due to the compositions and contents of the bonding and skeleton materials in the formulas, the suitable sintering pressure is limited (≤16 MPa), while the sintering temperature is relatively high (≥ 930℃), resulting in a lower relative ratio of the actual and theoretical densities (≤98%) for the diamond bit matrix. However, the high sintering temperature will cause thermal damage to the diamonds, …

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Recharge Water Types Of Coalbed Methane Wells: Controlling Effects On Water Yield And Countermeasures, Du Fengfeng, Ni Xiaoming, Zhang Yafei, Liu Yuru, Wang Wensheng Jun 2023

Recharge Water Types Of Coalbed Methane Wells: Controlling Effects On Water Yield And Countermeasures, Du Fengfeng, Ni Xiaoming, Zhang Yafei, Liu Yuru, Wang Wensheng

Coal Geology & Exploration

External water recharge of coalbed methane (CBM) wells leads to high water yield, thus affecting effective pressure propagation within coal seams and ultimately impacting gas production. This study aims to ascertain the influence of different types of recharge water on the water yield of CBM wells, as well as the characteristics of water yield and gas production of these wells under different recharge water types. Based on the exploration and development data of 25 CBM wells in the Shouyang block, this study presented general methods for obtaining the parameters for recharge water type classification and proposed the stepped method for …

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Design And Application Of Anti-Drop Drill Pipe With Fracture Self-Locking Function, Dong Changle Jun 2023

Design And Application Of Anti-Drop Drill Pipe With Fracture Self-Locking Function, Dong Changle

Coal Geology & Exploration

Drill pipe will inevitably break and drop during its long-term service, which not only seriously affects the drilling efficiency and the rate of hole formation, but also brings great economic losses to coal mines. In terms of drill pipe drop caused by the random fracture during drilling, the shortcomings of fishing tap were pointed out. By analyzing the fracture characteristics of drill pipe, it is concluded that the key to solve the problem of drill pipe drop is to develop the axial connection technology after the fracture of pin joint. Herein, an active anti-drop technology with fracture self-locking function was …

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Experimental Study On Co2 Storage In Coal Measure Gas Hydrates Reservoirs In Muli Coalfield, Lyu Wenyu, Lyu Chao, Zhang Wenzhong, Sun Qiang, Jia Hailiang, Tang Li'an Jun 2023

Experimental Study On Co2 Storage In Coal Measure Gas Hydrates Reservoirs In Muli Coalfield, Lyu Wenyu, Lyu Chao, Zhang Wenzhong, Sun Qiang, Jia Hailiang, Tang Li'an

Coal Geology & Exploration

Carbon Dioxide Geological Storage (CGS) is a promising technology for reducing the greenhouse gas emissions and mitigating the climate change. The hydrate-based CO2 storage in the abandoned gas hydrate reservoir can play a key role in CGS. In this paper, artificial cores of hydrate reservoir were prepared based on the basic physical properties of coal measure gas hydrate reservoir in Muli Coalfield, and the variations in density, porosity and permeability of the core with particle diameter of quartz sand were analyzed. The variations in CO2 hydrate saturation in core were analyzed based on the low-field Nuclear Magnetic Resonance …

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Numerical Simulations Of The Rapid Interception Mechanisms By The Borehole-Controlled Grouting With Grout-Conserving Bags Under Flowing Water, Yang Zhibin Jun 2023

Numerical Simulations Of The Rapid Interception Mechanisms By The Borehole-Controlled Grouting With Grout-Conserving Bags Under Flowing Water, Yang Zhibin

Coal Geology & Exploration

Grout-conserving bags. To characterize the local and overall development processes of the rapid interception more subtly and vividly, this study built a CFD-DEM fluid-solid coupling mathematical model of the roadway inlet under the given water head boundary according to the principle of a constant velocity. Then, given constant velocities of water inrush volumes of 2000 m3/h and 20000 m3/h, this study numerically simulated the construction process of water-blocking bodies by pouring and stacking aggregates with a grain size of 22 mm under the operating conditions with or without grout-conserving bags. The results show that: (1) Under …

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Deep Seismic Reflection Profiling Technology In Land Areas: A Review And Prospects, Yue Hangyu, Wang Xiaojiang, Wang Lei, Wang Kai, Zhang Baowei Jun 2023

Deep Seismic Reflection Profiling Technology In Land Areas: A Review And Prospects, Yue Hangyu, Wang Xiaojiang, Wang Lei, Wang Kai, Zhang Baowei

Coal Geology & Exploration

Deep seismic reflection profiling has been internationally proven to be a leading technology for deep earth exploration. With longer arrangement and greater energy than those used in oil seismic exploration, this technology can detect the fine-scaled structures and tectonic features from the earth surface to the upper mantle. Therefore, it is widely applied to the detection of continental and marine crust and upper mantle, with fruitful achievements having been made in revealing deep earth dynamic processes, expounding on the geotectonic evolution, determining the basin-mountain coupling, inferring the metallogenic and reservoir formation conditions, and analyzing earthquake disasters. This paper systematically reviews …

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Balance Analysis And Counterweight Optimization Design For Detection With Orientated Borehole Ground Penetrating Radar Antenna, Li Taotao, Xu Xianlei, Xu Hailong, Ouyang Bing, Wang Pengjie Jun 2023

Balance Analysis And Counterweight Optimization Design For Detection With Orientated Borehole Ground Penetrating Radar Antenna, Li Taotao, Xu Xianlei, Xu Hailong, Ouyang Bing, Wang Pengjie

Coal Geology & Exploration

Orientated borehole ground penetrating radar (OBGPR) can effectively solve the problem of orientated and detailed detection of geological conditions around the mine or oil well boreholes and engineering probe hole, etc. In view of difficult state control and unsatisfactory detection effect during antenna sagging due to the changeable medium in deep hole and the unreasonable counterweight of OBGPR antenna, the balance analysis and counterweight optimization design of orientated borehole ground penetrating radar antenna during detection was implemented in this paper. Firstly, analysis was conducted on the force of OBGPR antenna under the balance condition during the deep hole and well …

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Direct Current Resistivity Method For The Advance Prediction Of Water Hazards In Coal Mines Based On An Artificial Neural Network, Li Yuteng, Cheng Jianyuan, Lu Jingjin, Dai Fengqiang, Wu Zhengfei, Fang Zhe, Zhao Jiajia Jun 2023

Direct Current Resistivity Method For The Advance Prediction Of Water Hazards In Coal Mines Based On An Artificial Neural Network, Li Yuteng, Cheng Jianyuan, Lu Jingjin, Dai Fengqiang, Wu Zhengfei, Fang Zhe, Zhao Jiajia

Coal Geology & Exploration

The mine Direct Current (DC) resistivity method has the characteristics of high construction efficiency and low cost, which is widely used in the advanced detection of water hazards in coal mine heading face.With the continuous deepening of applications, higher requirements have been put forward for the advanced detection signal processing method of mine DC resistivity method. Based on the response information database obtained by finite element method and data reconstruction, the Levenberg-Marquardt (L-M) artificial neural network method is used to realize the advanced prediction of mine DC resistivity method. First, this study established an advanced prediction model of the DC …

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An Experimental Study On Factors Controlling The Proppant Transport In Hydraulic Fractures Of Coal Reservoirs, Su Xianbo, Fan Jian, Wang Ran, Wang Lufei, Zhao Fengzhen, Wang Qian Jun 2023

An Experimental Study On Factors Controlling The Proppant Transport In Hydraulic Fractures Of Coal Reservoirs, Su Xianbo, Fan Jian, Wang Ran, Wang Lufei, Zhao Fengzhen, Wang Qian

Coal Geology & Exploration

Effectively propping open hydraulic fractures in coal reservoirs plays an important role in ensuring the efficient production of coalbed methane (CBM). This study investigated the effects of fracture morphology and the volume, injection rate, and properties of fracturing fluids on proppant transport in fractures through visualized experiments. The results are as follows: (1) Proppants showed a relatively homogeneous distribution in simple fractures with a constant aperture. In contrast, they form room-and-pillar props composed of proppant pillars and proppant-free rooms in local simple fractures with varying apertures and reticular fractures due to the effects of the varying flow rates of fracturing …

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Soil Moisture Migration Mechanism And Its Ecological Effect In Cold And Arid Open-Pit Coal Mining Area, Wang Qiangmin, Zhao Chunhu, Wang Hao, Sun Jie, Yang Jian, Wang Wenke Jun 2023

Soil Moisture Migration Mechanism And Its Ecological Effect In Cold And Arid Open-Pit Coal Mining Area, Wang Qiangmin, Zhao Chunhu, Wang Hao, Sun Jie, Yang Jian, Wang Wenke

Coal Geology & Exploration

In order to explore the soil moisture migration mechanism and its ecological effect in the cold and arid open-pit coal mining area, a long-term in-situ test was carried out to observe the soil moisture, taking the open-pit coal mine in eastern Mongolia grassland area as the study area. The results show that: The shallow soil moisture content is mainly affected by rainfall in non-freezing period, while the soil moisture content is significantly affected by soil temperature in freezing period. Besides, the saturated permeability coefficient of soil in depth less than 50 cm is greater than 150 cm/d, but that of …

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Design, Development And Implementation Of A Comprehensive Evaluation System For Multi-Source Information On Water Inrush From Coal Seam Floor, Li Bo, Luo Yulan, Fan Juan, Guo Xiaoming, Li Menghua Jun 2023

Design, Development And Implementation Of A Comprehensive Evaluation System For Multi-Source Information On Water Inrush From Coal Seam Floor, Li Bo, Luo Yulan, Fan Juan, Guo Xiaoming, Li Menghua

Coal Geology & Exploration

The evaluation technology of multi-source information fusion is an important method for the prediction of water inrush from the coal seam floor. However, this method has the deficiencies, such as high professional technical requirements, complicated and tedious evaluation process, and insufficient intelligence during its application. In this study, the design principle, design idea, development mode, and development method of a multi-source information comprehensive evaluation system for water inrush from coal seam bottom were systematically described according to the characteristics of the technical process of water inrush risk evaluation. The key functions of system were built, including the universal evaluation index …

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Mine Water Inrush Prediction Method Based On Vmd-Dbn Model, Liu Hui, Liu Guiqin, Ning Dianyan, Fan Juan, Chen Weiming Jun 2023

Mine Water Inrush Prediction Method Based On Vmd-Dbn Model, Liu Hui, Liu Guiqin, Ning Dianyan, Fan Juan, Chen Weiming

Coal Geology & Exploration

In the process of coal mining, the loss of people and property caused by mine water inrush is extremely serious. To prevent the occurrence of water inrush accidents and grasp the law of change of water inrush, the water inrush prediction and forecasting, especially the accurate estimation of mine water inrush, is very important, which is also an important task in the prevention and control of mine water damage. To increase the prediction accuracy of mine water inrush, an efficient time series prediction model combining Variational Mode Decomposition (VMD) and Deep Belief Network (DBN) was proposed for the series of …

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